HYGIENIC WASHING DEVICE

Abstract

 According to an aspect of the invention, a sanitary washing apparatus includes: jetting means configured to jet water in a hollow conic shape; fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to fill a hollow portion of the water jetted in the hollow conic shape with the granulated water flows before the water jetted in the hollow conic shape impinges on the human private parts; and liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means.

Description

[Field]

[0001] This invention relates generally to a sanitary washing apparatus, and more particularly to a sanitary washing apparatus for washing with water the human private parts of a user seated on a sit-down toilet stool.

[Background]

[0002] As a technique for expanding the washing range (washing area at the time of water impingement) without moving the nozzle for washing private parts, there is known a human body washing apparatus capable of jetting spirally swirled water from the jetting hole of a nozzle (Patent Documents 1 and 2). The technique for producing spirally swirled jetting water (hollow-conic-shape jetting water) is a useful technique capable of adjusting the washing range by the degree of swirling. However, in the hollow-conic-shape jetting water, a hollow portion inside the hollow conic shape, i.e., an emptied portion, occurs at the time of impingement. Thus, there is room for improvement with regard to the washing performance in the emptied portion. More specifically, for instance, dirt at the time of defecation is attached around the anus. In particular, in the case of loose stool in bad physical condition, the dirt is attached over a wide range in four directions. Thus, further improvement is required to respond to the demand for washing a wide range gently and quickly at once.

[0003] In this context, there is known a sanitary washing apparatus for further jetting a rectilinear flow in the hollow portion inside the swirled squirt flow (Patent Document 3). Thus, while ensuring a large washing area by the swirled squirt flow, a strong feeling of washing can be obtained by the rectilinear flow. However, in the sanitary washing apparatus described in Patent Document 3, because a rectilinear flow is further jetted in the hollow portion inside the swirled squirt flow, the washing pressure in the central part of the washing area is high. This may unnecessarily apply strong stimuli to the anal part. Thus, for users having a laceration due to hemorrhoids around the anal part or an abrasion due to excessive wipe-up, a problem remains in view of the feeling of washing required for bottom washing of a user in bad physical condition desiring to wash a wide range gently and quickly at once.

[0004] Furthermore, there is known a private parts washing apparatus capable of changing the washing area of the squirt pattern by changing the state of interference between the axial squirt flow and the tangential squirt flow (Patent Document 4). However, in the private parts washing apparatus described in Patent Document 4, because the axial squirt flow is used, the washing pressure in the central part of the washing area is high. This may unnecessarily apply strong stimuli to the anal part. Thus, for users having a laceration due to hemorrhoids around the anal part or an abrasion due to excessive wipe-up, a problem remains in view of the feeling of washing required for bottom washing of a user in bad physical condition desiring to wash a wide range gently and quickly at once.

[0005] On the other hand, there is known a jetting apparatus capable of jetting water fragments in a swirling state (Patent Document 5). However, if water fragments are jetted in such a wide range as to be required for bottom washing of a user in bad physical condition desiring to wash a wide range gently and quickly at once, the water fragments may drift in the air and scatter to the outside of the desired washing area. Then, the scattered water may be attached to the thigh and the like of the user seated on the toilet seat, and the user may feel discomfort. Furthermore, the impinging water pressure of the water fragments at the time of impingement is very low. Thus, the water fragments can only give the user an excessively low feeling of washing, leaving the problem of failing to obtain a feeling of satisfaction and achievement required for the act of washing the bottom.

[Citation List]

[Patent Literature]

[0006] 

[Patent Citation 1] JP 2001-90155 A (Kokai)

[Patent Citation 2] JP 2001-90151 A (Kokai)

[Patent Citation 3] JP 2007-100370 A (Kokai)

[Patent Citation 4] JP 2001-90154 A (Kokai)

[Patent Citation 5] JP 3848886

[Summary of Invention]

[Problems to be Solved by the invention]

[0007] This invention is based on the recognition of these problems. An object of the invention is to provide a sanitary washing apparatus capable of washing the washing area gently and quickly at once by uniform impingement of water on a larger washing area than the conventional bottom washing. In bottom washing of a user in bad physical condition, the sanitary washing apparatus is to be capable of realizing a high feeling of water volume required for the act of bottom washing without unnecessarily causing discomfort such as a strong feeling of stimuli and a feeling of being swept in the central part. Furthermore, the sanitary washing apparatus is to be capable of suppressing scattering of water to the outside of the desired washing area.

[Means for Solving the Problem]

[0008] According to an aspect of the invention,

[Brief Description of Drawings]

[0009] 

[Fig. 1]
FIG. 1 is a perspective schematic view showing a toilet apparatus equipped with a sanitary washing apparatus according to an embodiment of the invention.

[Fig. 2]
FIG. 2 is a conceptual schematic view showing a main part configuration of the sanitary washing apparatus according to this embodiment.

[Fig. 3]
FIG. 3 is a conceptual schematic view generally showing the state of water jetted from the nozzle of this embodiment.

[Fig. 4]
FIG. 4 is a graph showing an example of impinging water pressure and impinging water amount at the impingement part of the water.

[Fig. 5]
FIG. 5 is a graph showing another example of impinging water pressure and impinging water amount at the impingement part of the water.

[Fig. 6]
FIG. 6 is a sectional schematic view showing a nozzle according to the example of this embodiment.

[Fig. 7]
FIG. 7 is a sectional schematic view showing a nozzle according to a com parative example.

[Fig. 8] FIG. 8 is a sectional schematic view illustrating a variation of the throat.

[Fig. 9]
FIG. 9 is a sectional schematic view showing a nozzle according to an alternative example of this embodiment.

[Fig. 10]
FIG. 10 is a graph showing the timing of driving the pulsation pump and the velocity of the liquid film of this example.

[Fig. 11]
FIG. 11 is a schematic sectional view illustrating the state of the granular water flows of interval a-b in FIG. 10.

[Fig. 12]
FIG. 12 is a schematic sectional view illustrating the state of the granular water flows of interval a-b in FIG. 10.

[Fig. 13]
FIG. 13 is a schematic sectional view illustrating the state of the granular water flows of interval c-d in FIG. 10.

[Fig. 14]
FIG. 14 is a schematic sectional view illustrating the state of the granular water flows of interval c-d in FIG. 10.

[Fig. 15]
FIG. 15 is a schematic sectional view showing the state of the granular water flows at the bottom impingement location of this example.

[Fig. 16]
FIG. 16 is a graph showing the spatial density of the granular water flows at the bottom impingement location of this example.

[Fig. 17]
FIG. 17 is a conceptual schematic view showing a main part configuration of a sanitary washing apparatus according to the alternative embodiment of this invention.

[Fig. 18]
FIGS. 18A and 18B are conceptual schematic views generally showing the state of water jetted from the nozzle of this embodiment.

[Fig. 19]
FIG. 19 is a conceptual schematic view generally showing the state of water jetted from the nozzle of this embodiment.

[Fig. 20]
FIG. 20 is a graph showing the impinging water force of the water at a position separated by a prescribed distance from the impingement part or the jetting hole.

[Fig. 21]
FIG. 21 is a sectional schematic view illustrating the example of the nozzle of this embodiment.

[Fig. 22]
FIG. 22 is a sectional schematic view illustrating the internal structure of the pulsation generating means of this embodiment.

[Fig. 23]
FIGS. 23A and 23B are graphs illustrating a voltage waveform applied to the pulsation generating means and a flow velocity waveform of water on the downstream side of the pulsation generating means.

[Fig. 24]
FIG. 24 is a graph illustrating the velocity distribution of particles passing near the impingement position.

[Fig. 25]
FIG. 25 is a graph illustrating the spatial occupancy ratio of particles passing near the impingement position.

[Fig. 26]
FIGS. 26A to 26E are photographs showing the state of the water jetted from the nozzle of this embodiment.

[Fig. 27]
FIGS. 27A to 27D are photographs showing the state of the water jetted from the nozzle of this embodiment.

[Fig. 28]
FIG. 28 is a conceptual schematic view showing a main part configuration of a sanitary washing apparatus according to the further alternative embodiment of this invention.

[Fig. 29]
FIG. 29 is a graph illustrating the spatial occupancy ratio of particles passing near the impingement position.

[Fig. 30]
FIGS. 30A to 30C are timing charts for describing the operation of the pulsation generating means of this embodiment.

[Fig. 31]
FIGS. 31A to 31C are timing charts for describing the example of the operation of the water force adjusting means.

[Fig. 32]
FIG. 32 is a plan schematic view for describing the timings at which the first water flow group and the second water flow group impinge on the impingement position.

[Fig. 33]
FIG. 33 is a plan schematic view for describing liquid drops passing near the impingement position of this example.

[Fig. 34]
FIG. 34 is a graph illustrating the number of liquid drops in the case where the first water flow group cannot catch up with the second water flow group before the impingement position.

[Fig. 35]
FIG. 35 is a graph illustrating the number of liquid drops in the case where the first water flow group catches up with the second water flow group at the impingement position.

[Fig. 36]
FIGS. 36A to 36C are timing charts for describing the alternative example of the operation of the water force adjusting means.

[Fig. 37]
FIG. 37 is a schematic view for describing a method for measuring the vibration state of the impingement part by the water.

[Fig. 38]
FIGS. 38A and 38B are graphs illustrating an example of the measurement result of the vibration state of the impingement part by the water.

[Fig. 39]
FIGS. 39A and 39B are graphs for describing the relationship between the feeling of fullness and the presence or absence of pulsation.

[Fig. 40]
FIGS. 40A and 40B are a table and a graph for describing the relationship between the feeling of fullness and the frequency.

[Description of Embodiments]

[0010] A first invention is a sanitary washing apparatus for jetting water from a jetting hole of a nozzle used in bottom washing toward human private parts, the apparatus including: jetting means configured to jet water in a hollow conic shape from the jetting hole; fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to fill a hollow portion of the water jetted in the hollow conic shape with the granulated water flows before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts; and liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means.

[0011] In this sanitary washing apparatus, the water squirted from the nozzle is first jetted from the jetting hole in a hollow conic shape as a liquid film having a hollow portion in the central part. In the following, for convenience of description, the water jetted in a hollow conic shape in this manner is referred to as "hollow-conic-shape jetting water". The hollow portion of the hollow-conic-shape jetting water is fractured by the fracturing means and transitions to granulated water flows (hereinafter referred to as "granular water flows" for convenience of description) before impinging on the human private parts. Thus, in the state in which the hollow portion is filled with the granular water flows, the hollow-conic-shape jetting water impinges on a wider range of the human private parts of the user seated on the toilet seat.

[0012] Dirt at the time of defecation may be attached around the anus. I n particular, in the case of loose stool in bad physical condition, the dirt may be attached over a wide range in four directions. The sanitary washing apparatus of this invention can respond to the demand for washing the wide range gently and quickly at once. That is, the occurrence of the emptied portion at the time of impingement is suppressed. Thus, the problem about the washing performance in the emptied portion can be solved.

[0013] Here, the washing range of the water (washing area at the time of impingement) is e.g. approximately 23-33 mm in diameter. The hollow-conic-shape jetting water impinges on the human private parts in the state in which the liquid film is fractured and granulated. At this time, the liquid film thickness expanding means expands the liquid film of the water jetted in the hollow conic shape. Thus, the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole is made thicker than the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting means.

[0014] Furthermore, the granular water flows filling the hollow portion of the hollow-conic-shape jetting water impinge on the vicinity of the center of the washing area. Thus, the washing pressure in the central part of the washing area is lower than in the case of impingement of the conventional rectilinear flow. Accordingly, there is little danger that strong stimuli are unnecessarily applied to the anal part. Thus, also for users having a laceration due to hemorrhoids around the anal part or an abrasion due to excessive wipe-up, the sanitary washing apparatus of this invention can solve the problem of the feeling of washing required for bottom washing of a user desiring to wash a wide range gently and quickly at once. Accordingly, bottom washing with a very comfortable feeling of washing can be realized.

[0015] Furthermore, the sanitary washing apparatus of this invention enables water to impinge at once on a wider range than the conventional bottom washing. Thus, there is no need to move the impingement position by moving the nozzle in the front-back direction and left-right direction. Furthermore, there is no need for the user seated on the toilet seat to move the seated position by oneself to move the impingement position. Thus, the sanitary washing apparatus of this invention has little danger of giving a feeling of being swept in washing the human private parts in a wide range. Also for this reason, the sanitary washing apparatus of this invention gives no discomfort of the feeling of being swept in washing the bottom of a user in bad physical condition sensitive to stimuli. Accordingly, bottom washing with a very comfortable feeling of washing can be realized.

[0016] In the sanitary washing apparatus of this invention, the water jetted from the nozzle is jetted as hollow-conic-shape jetting water. The water is fractured by the fracturing means at a position spaced to some extent from the nozzle and transitions to granular water flows. More specifically, the fracturing means fractures the liquid film by generating a flow of water in the direction traversing the liquid film inside the water jetted in the hollow conic shape. Thus, air is likely to enter the hollow portion of the hollow-conic-shape jetting water. Accordingly, the pressure in the hollow portion of the hollow-conic-shape jetting water can be prevented from further decreasing. This can suppress the occurrence of liquid film rippling in the hollow-conic-shape jetting water.

[0017] Here, the "liquid film rippling" is described. First, the pressure in the hollow portion of the hollow-conic-shape jetting water is lower than the pressure outside the water jetted in the hollow conic shape. Here, if the hollow-conic-shape jetting water continues to expand as a liquid film without being fractured, the thickness of the liquid film is thinned with the expansion of the jetting water diameter (cone diameter). Then, the liquid film of the hollow-conic-shape jetting water is made more susceptible to the pressure difference between the hollow portion of the hollow-conic-shape jetting water and the portion outside the water jetted in the hollow conic shape. Thus, due to the pressure difference between the hollow portion of the hollow-conic-shape jetting water and the portion outside the hollow-conic-shape jetting water, the hollow-conic-shape jetting water at a position spaced to some extent from the jetting hole experiences a phenomenon like rippling while retaining the state of the liquid film. In this specification, such a phenomenon is referred to as "liquid film rippling".

[0018] If the liquid film of the hollow-conic-shape jetting water is fractured after the occurrence of liquid film rippling, the fractured and granulated water flows scatter in irregular directions due to the effect of rippling, and is likely to scatter to the outside of the desired washing area. The scattered water is attached to the thigh and the like of the user seated on the toilet sea, and the user may feel discomfort.

[0019] Liquid film rippling occurs at a position where the thickness of the liquid film is thinned. Furthermore, the occurrence of rippling further elongates the trajectory of the liquid film. Thus, the thickness of the liquid film becomes thinner. That is, if liquid film rippling occurs in the hollow-conic-shape jetting water, the hollow-conic-shape jetting water is fractured into particles having a relatively small diameter. This fractured particle has a small diameter and mass. Thus, the small particle drifts in the air, and is likely to scatter to the outside of the desired washing area. Then, the scattered water is attached to the thigh and the like of the user seated on the toilet seat, and the user may feel discomfort.

[0020] In contrast, the sanitary washing apparatus of this invention can suppress the occurrence of liquid film rippling in the hollow-conic-shape jetting water. Thus, scattering of the granulated water flows in irregular directions due to the effect of rippling, and scattering of water to the outside of the desired washing area can be suppressed. Furthermore, unnecessary wetting of the portion outside the desired washing area can be suppressed. Furthermore, fracturing of the hollow-conic-shape jetting water into particles having a smaller diameter can be suppressed. That is, by preventing the occurrence of liquid film rippling, the diameter of the granular water flow can be increased. Furthermore, as described above, the liquid film thickness expanding means expands the liquid film of the water jetted in the hollow conic shape. Thus, the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole is made thicker than the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting means. Accordingly, the diameter of the granular water flow can be increased more reliably.

[0021] Thus, there is little danger that the granular water flows drift in the air. There is little danger that the granular water flows scatter to the outside of the desired washing area. That is, scattering of water to the outside of the desired washing area can be suppressed. Furthermore, unnecessary wetting of the portion outside the desired washing area can be suppressed. This can further solve the problem that the user seated on the toilet seat feels discomfort due to unnecessary wetting of the portion outside the desired washing area.

[0022] By preventing the occurrence of liquid film rippling and expanding the liquid film of the water jetted in the hollow conic shape, the diameter of the granular water flow can be increased. Thus, the impinging water pressure and impinging water amount at the impingement part can be made higher. Here, the term "impinging water pressure" refers to the momentum per unit area, representing the power of removing, stripping, or releasing dirt. On the other hand, the term "impinging water amount" refers to the amount of water impinging per unit time, representing the power of washing dirt away. Thus, dirt at the time of defecation can be removed or released more rapidly, and can be washed away more rapidly.

[0023] In the sanitary washing apparatus of this invention, the impinging water pressure at the impingement part of the water is generally equal in the central part and in the outer peripheral part of the impingement part. Alternatively, the impinging water pressure at the impingement part of the water is higher in the outer peripheral part than in the central part of the impingement part.

[0024] Here, the outer peripheral part of the desired washing area is an area desired to be actively washed particularly in the case of loose stool in bad physical condition, because the dirt is attached over a wide range in four directions. The impinging water pressure in the outer peripheral part is generally equal to or higher than the impinging water pressure in the central part. Thus, the water with high washing power impinges on the area where the dirt is to be removed. On the other hand, the water with low impinging water pressure impinges on the center of the anus. Thus, unnecessarily strong stimuli are not applied thereto. Accordingly, the sanitary washing apparatus of this invention can remove or release more rapidly the dirt attached over a wide range in four directions in the case of loose stool in bad physical condition. Furthermore, bottom washing with a very comfortable feeling of washing can be realized. Thus, the sanitary washing apparatus of this invention is also suitable as an apparatus used in the case of loose stool in bad physical condition.

[0025] Furthermore, in the sanitary washing apparatus of this invention, the impinging water amount at the impingement part of the water is generally equal in the central part and in the outer peripheral part of the impingement part. Alternatively, the impinging water amount at the impingement part of the water is larger in the outer peripheral part than in the central part of the impingement part.

[0026] Here, as described above, the outer peripheral part of the desired washing area is an area desired to be actively washed particularly in the case of loose stool in bad physical condition, because the dirt is attached over a wide range in four directions. The impinging water amount in the outer peripheral part is generally equal to or larger than the impinging water amount in the central part. Thus, a sufficient amount of water impinges on the area where the dirt is to be removed. On the other hand, the water with a small impinging water amount impinges on the center of the anus. This can suppress discomfort due to washing with an unnecessarily large amount of water. Thus, the dirt attached over a wide range is captured more reliably by the impinging water, and washed away more rapidly. Furthermore, bottom washing with a very comfortable feeling of washing can be realized. Thus, the sanitary washing apparatus of this invention is also suitable as an apparatus used in the case of loose stool in bad physical condition.

[0027] A second invention is the sanitary washing apparatus of the first invention wherein the liquid film thickness expanding means makes the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker by making flow velocity of the water flowing out of the liquid film thickness expanding means slower than flow velocity of the water flowing into the liquid film thickness expanding means.

[0028] In this sanitary washing apparatus, the liquid film thickness expanding means makes the thickness of the liquid film of the water jetted in the hollow conic shape thicker by making the flow velocity of the water flowing out of the liquid film thickness expanding means slower than the flow velocity of the water flowing into the liquid film thickness expanding means. Thus, the liquid film thickness expanding means can averagely expand the thickness of the liquid film of the water flowing inside the liquid film thickness expanding means. Accordingly, the liquid film thickness expanding means can prevent more reliably the generation of particles having a smaller diameter due to variation in the thickness of the liquid film. Thus, the sanitary washing apparatus of this invention can realize bottom washing with a very comfortable feeling of washing.

[0029] A third invention is the sanitary washing apparatus of the second invention wherein the liquid film thickness expanding means makes the flow velocity of the water slower by making resistance applied to the water flowing out of the liquid film thickness expanding means larger than resistance applied to the water flowing into the liquid film thickness expanding means.

[0030] In this sanitary washing apparatus, the liquid film thickness expanding means makes the flow velocity of the water slower by making the resistance applied to the water flowing out of the liquid film thickness expanding means larger than the resistance applied to the water flowing into the liquid film thickness expanding means. Thus, the water poured into the liquid film thickness expanding means is gradually decelerated on the inflow side of the liquid film thickness expanding means, and sharply decelerated on the outflow side of the liquid film thickness expanding means. This can suppress that the water poured into the liquid film thickness expanding means is granulated under large resistance or impact when the velocity is faster. Thus, while maintaining the water flowing inside the liquid film thickness expanding means in the state of the liquid film, the water can be decelerated more stably. Accordingly, the thickness of the liquid film can be expanded more reliably.

[0031] A fourth invention is the sanitary washing apparatus of the second invention wherein the liquid film thickness expanding means is a throat formed in a tubular shape and having a flow channel inside, and the throat receives the water jetted in the hollow conic shape from the jetting means at an inner wall of the flow channel and slows down the flow velocity of the water by a frictional force occurring when the water passes along the inner wall of the flow channel.

[0032] In this sanitary washing apparatus, the liquid film thickness expanding means is a throat formed in a tubular shape and having a flow channel inside. The throat receives the water jetted in the hollow conic shape from the jetting means at an inner wall of the flow channel and slows down the flow velocity of the water by a frictional force occurring when the water passes along the inner wall of the flow channel. Thus, the throat can receive the impact of the water uniformly in the circumferential direction. Accordingly, the throat can expand the thickness of the liquid film in the state of smaller variation in the circumferential direction of the water and jet the water from the jetting hole. Thus, the throat can prevent more reliably the generation of particles having a smaller diameter due to variation in the thickness of the liquid film.

[0033] A fifth invention is the sanitary washing apparatus of the fourth invention wherein a portion between the jetting means and the throat is opened to atmosphere.

[0034] In this sanitary washing apparatus, the portion between the jetting means and the throat is opened to the atmosphere. Thus, the occurrence of negative pressure between the outer peripheral side of the liquid film of the water jetted in the hollow conic shape from the jetting means and the inner wall of the flow channel of the throat can be suppressed. This can suppress that the liquid film of the water jetted in the hollow conic shape from the jetting means is granulated inside the throat by being pulled by the negative pressure and placed in an unstable state. That is, the state of the liquid film can be maintained inside the throat, and the thickness of the liquid film can be expanded more reliably.

[0035] A sixth invention is the sanitary washing apparatus of the second invention wherein the nozzle includes: a jetting port configured to jet hollow-conic-shape water formed by a swirling flow; and an annular part configured to receive the hollow-conic-shape water jetted from the jetting port, to decelerate the water while maintaining a state of the liquid film by passing the water along an inner wall, and to make the thickness of the liquid film of the water thicker, and the jetting hole configured to jet the water passed through the annular part in the hollow conic shape is provided on downstream side in the annular part, and the liquid film of the hollow-conic-shape water jetted from the jetting hole is fractured.

[0036] In this sanitary washing apparatus, an annular part is provided between the jetting port and the jetting hole. The annular part is configured to receive the hollow-conic-shape water jetted from the jetting port, to decelerate the water while maintaining a state of the liquid film by passing the water along an inner wall, and to make the thickness of the liquid film of the water thicker. Thus, by a very simple configuration, the thickness of the liquid film can be thickened more reliably.

[0037] A seventh invention is the sanitary washing apparatus used in bottom washing, including: a nozzle including a jetting hole and configured to jet water from the jetting hole toward human private parts, the nozzle being configured to jet: first jetting water including a flow toward a central part of the human private parts after impinging on an outer peripheral part of the human private parts, and second jetting water including a flow toward the outer peripheral part of the human private parts after impinging on the central part of the human private parts, and impinging water force at the human private parts of the first jetting water being larger than impinging water force at the human private parts of the second jetting water.

[0038] I n this sanitary washing apparatus, the first jetting water impinges on the outer peripheral part of the human private parts. The impinging water force at the human private parts of the first jetting water is larger than the impinging water force at the human private parts of the second jetting water. Thus, the first jetting water can provide a sufficient feeling of volume. Furthermore, a sufficient washing power can be ensured by the flow included in the first jetting water after impinging on the human private parts and the flow included in the second jetting water after impinging on the human private parts. The nozzle 410 jets water divided into the first jetting water for providing the feeling of volume and the second jetting water for ensuring the washing power. Thus, at a small flow rate, the feeling of volume can be provided, and the washing power can be ensured.

[0039] A eighth invention is the sanitary washing apparatus of the seventh invention wherein flow velocity of the first jetting water is faster than flow velocity of the second jetting water.

[0040] In this sanitary washing apparatus, the flow velocity of the first jetting water is faster than the flow velocity of the second jetting water. Furthermore, the impinging water force at the human private parts of the first jetting water is larger than the impinging water force at the human private parts of the second jetting water. That is, by increasing the flow velocity of the water jetted from the nozzle, the impinging water force at the human private parts can be increased. Accordingly, the impinging water force at the human private parts can be increased even without increasing the amount of water jetted from the nozzle, and a higher feeling of volume can be provided. Thus, at a small flow rate, the feeling of volume can be provided, and the washing power can be ensured.

[0041] A ninth invention is the sanitary washing apparatus of the seventh invention wherein the first jetting water includes ring-shaped jetting water, and the second jetting water includes solid jetting water.

[0042] In this sanitary washing apparatus, the first jetting water for providing the feeling of volume includes ring-shaped jetting water. Thus, the first jetting water impinges as ring-shaped jetting water on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, a firm feeling of volume can be provided. On the other hand, the second jetting water for ensuring washing power includes solid jetting water. Thus, while ensuring washing power, the second jetting water can quickly wash away dirt in the central part of the human private parts, and gently wash the central part of the human private parts.

[0043] A tenth invention is the sanitary washing apparatus of the seventh invention wherein the first jetting water and the second jetting water are alternately jetted from the jetting hole.

[0044] I n this sanitary washing apparatus, the first jetting water and the second jetting water are jetted, not simultaneously but alternately, from the jetting hole. This can cause the user to feel the water as continuous jetting water. Thus, at a small flow rate, a sufficient feeling of volume can be provided, and a sufficient washing power can be ensured.

[0045] A eleventh invention is the sanitary washing apparatus of the tenth invention further including: pulsation generating means configured to provide pulsation to the water jetted from the jetting hole to alternately jet the first jetting water and the second jetting water.

[0046] In this sanitary washing apparatus, the pulsation generating means can alternately jet the first jetting water and the second jetting water. Thus, by a simpler configuration, a sufficient feeling of volume can be provided, and a sufficient washing power can be ensured.

[0047] A twelfth invention is the sanitary washing apparatus for bottom washing by jetting water from a jetting hole of a nozzle toward human private parts, the apparatus including: jetting means configured to jet water in a hollow conic shape from the jetting hole; fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to pour the granulated water flows into a hollow portion of the water jetted in the hollow conic shape before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts; liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means; and fracturing position varying means configured to periodically vary position of fracturing the liquid film of the water jetted in the hollow conic shape from the jetting hole.

[0048] In this sanitary washing apparatus, the fracturing position varying means periodically varies the position of fracturing the liquid film of the water jetted in the hollow conic shape from the jetting hole. Thus, after the liquid film is fractured, the particle diameter and flow velocity of the granulated water flows are periodically varied. This can provide an adequate feeling of volume required for bottom washing, and gently wash the human private parts.

[0049] A thirteenth invention is the sanitary washing apparatus of the twelfth invention wherein the fracturing position varying means changes flow velocity of the water jetted from the jetting hole.

[0050] I n this sanitary washing apparatus, in the case where the flow velocity of the water is faster, the liquid film is fractured in a thicker and longer state. Thus, after the liquid film is fractured, granulated water flows having a larger particle diameter and a faster flow velocity are generated. Furthermore, in this case, because the liquid film is fractured in a longer state, the liquid film is fractured in a more spread state. Thus, the granulated water flows impinge on the outer peripheral part of the human private parts with a larger particle diameter and a faster flow velocity.

[0051] On the other hand, in the case where the flow velocity of the water is slower, the liquid film is fractured in a thinner and shorter state. Thus, after the liquid film is fractured, granulated water flows having a smaller particle diameter and a slower flow velocity are generated. Furthermore, in this case, because the liquid film is fractured in a shorter state, the liquid film is fractured in a less spread state. Thus, the granulated water flows impinge on the central part of the human private parts with a smaller particle diameter and a slower flow velocity.

[0052] Thus, the impinging water force at the outer peripheral part of the human private parts can be increased. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, a sufficient feeling of volume or a firm feeling of volume required for bottom washing can be provided. On the other hand, the impinging water force at the central part of the human private parts can be decreased. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. Thus, the feeling of washing required for bottom washing of a user desiring to wash a wide range gently and quickly at once can be realized.

[0053] A fourteenth invention is the sanitary washing apparatus of the thirteenth invention wherein the water jetted in the hollow conic shape from the jetting hole is divided into at least one of first jetting water including ring-shaped jetting water and second jetting water including solid jetting water by the fracturing position varying means and impinges on the human private parts, and the fracturing position varying means alternately divides the water jetted in the hollow conic shape from the jetting hole into the first jetting water and the second jetting water.

[0054] In this sanitary washing apparatus, as a result, the first jetting water including ring-shaped jetting water and the second jetting water including solid jetting water are alternately jetted. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Thus, at a small flow rate, the feeling of volume can be provided, and the washing power can be ensured. Furthermore, a wide range can be washed gently and quickly at once.

[0055] A fifteenth invention is the sanitary washing apparatus of the fourteenth invention wherein position where liquid film of the first jetting water is fractured is located on the human private parts side of position where liquid film of the second jetting water is fractured, and the first jetting water impinges on the human private parts in a state of maintaining the ring-shaped jetting water.

[0056] In this sanitary washing apparatus, the water can be caused to impinge on the human private parts in the state of maintaining the ring-shaped jetting water, or in other words, before most of the granulated water flows flow into the hollow portion. This can apply a larger impinging water force to the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, the feeling of volume required for bottom washing can be provided.

[0057] A sixteenth invention is the sanitary washing apparatus of the thirteenth invention wherein a plurality of the granulated water flows fractured by the fracturing position varying means and having mutually different flow velocities independently impinge on the human private parts.

[0058] In this sanitary washing apparatus, at a small flow rate, the feeling of emptiness of the hollow portion can be suppressed, and a wide range can be washed gently and quickly at once.

[0059] A seventeenth invention is the sanitary washing apparatus for bottom washing by jetting water from a jetting hole of a nozzle toward human private parts, the apparatus including: jetting means configured to jet water in a hollow conic shape from the jetting hole; fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to pour the granulated water flows into a hollow portion of the water jetted in the hollow conic shape before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts; and liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means, the granulated water flows including a first water flow group and a second water flow group having a smaller particle diameter and a slower flow velocity than the first water flow group, and the first water flow group and the second water flow group independently impinging on the human private parts.

[0060] In this sanitary washing apparatus, by the first water flow group having a larger particle diameter and a faster flow velocity, a sufficient feeling of volume required for bottom washing can be realized. Furthermore, by the second water flow group having a smaller particle diameter and a slower flow velocity, a wide range can be washed gently and quickly at once without discomfort experienced at the time of washing with e.g. an unnecessarily large flow rate. Furthermore, the first water flow group and the second water flow group independently impinge on the human private parts. This can suppress the feeling of emptiness of the hollow portion and uniformly wash a wide range. Thus, at a small flow rate, the feeling of volume can be provided, and comfortable bottom washing can be realized.

[0061] A eighteenth invention is the sanitary washing apparatus of the seventeenth invention wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

[0062] In this sanitary washing apparatus, the first water flow group having a larger particle diameter and a faster flow velocity impinges on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, a sufficient feeling of volume or a firm feeling of volume can be provided. Furthermore, the second water flow group having a smaller particle diameter and a slower flow velocity impinges on the central part of the human private parts where dirt is likely to be attached. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. Thus, also for users having hemorrhoids, lacerations, or abrasions due to excessive wipe-up around the human private parts, a wide range can be washed gently and quickly at once.

[0063] A nineteenth invention is the sanitary washing apparatus of the seventeenth invention wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

[0064] In this sanitary washing apparatus, the feeling of volume required for bottom washing can be provided, and comfortable bottom washing can be realized.

[0065] A twentieth invention is the sanitary washing apparatus of the seventeenth invention wherein the first water flow group and the second water flow group are alternately generated from the granulated water flows.

[0066] In this sanitary washing apparatus, as a result, the first water flow group and the second water flow group are alternately jetted from the jetting hole. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Thus, at a small flow rate, the feeling of volume can be provided, and a wide range can be washed gently and quickly at once.

[0067] A twenty-first invention is the sanitary washing apparatus of the seventeenth invention wherein time interval at which the first and second water flow groups impinge on the human private parts is a time interval at which a human feels the water as continuous jetting water.

[0068] In this sanitary washing apparatus, by the first water flow group having a larger particle diameter and a faster flow velocity, a sufficient impinging water force required for bottom washing can be provided. On the other hand, by the second water flow group having a smaller particle diameter and a slower flow velocity, a wide range can be washed gently and quickly at once without discomfort experienced at the time of washing with e.g. an unnecessarily large flow rate. Furthermore, the water is caused to impinge with a time interval at which a human feels the water as continuous jetting water. Thus, at a smaller flow rate, an adequate feeling of volume required for bottom washing can be provided to a wider range. Furthermore, a sanitary washing apparatus capable of realizing comfortable bottom washing can be provided.

[0069] A twenty-second invention is the sanitary washing apparatus of the twenty-first invention wherein surface of the human private parts is vibrated in accordance with the time interval, and frequency of the vibration of the surface is 50 hertz or more and 100 hertz or less.

[0070] In this sanitary washing apparatus, an adequate feeling of volume (feeling of fullness) required for bottom washing can be provided. In the case where the frequency of the surface of the human private parts is lower than 50 hertz, the user feels a feeling of interruption of the jetting water, and feels discomfort. On the other hand, in the case where the frequency of the surface of the human private parts is higher than 100 hertz, while the user does not feel a feeling of interruption of the jetting water, the user cannot feel a feeling of vibration. Thus, the user cannot feel an adequate feeling of volume required for bottom washing.

[0071] A twenty-third invention is the sanitary washing apparatus of the twenty-first invention further including: pulsation generating means configured to provide pulsation to the water jetted from the jetting hole to produce the first water flow group and the second water flow group, wherein frequency of the pulsation provided by the pulsation generating means is 50 hertz or more and 100 hertz or less.

[0072] In this sanitary washing apparatus, an adequate feeling of volume (feeling of fullness) required for bottom washing can be provided. In the case where the frequency of the pulsation provided by the pulsation generating means is lower than 50 hertz, the user feels a feeling of interruption of the jetting water, and feels discomfort. On the other hand, in the case where the frequency of the pulsation provided by the pulsation generating means is higher than 100 hertz, while the user does not feel a feeling of interruption of the jetting water, the user cannot feel a feeling of vibration. Thus, the user cannot feel an adequate feeling of volume required for bottom washing.

[0073] A twenty-fourth invention is the sanitary washing apparatus of the twenty-first invention wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

[0074] In this sanitary washing apparatus, the first water flow group having a larger particle diameter and a faster flow velocity impinges on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, a sufficient feeling of volume or a firm feeling of volume can be provided. Furthermore, the second water flow group having a smaller particle diameter and a slower flow velocity impinges on the central part of the human private parts where dirt is likely to be attached. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. Thus, also for users having hemorrhoids, lacerations, or abrasions due to excessive wipe-up around the human private parts, a wide range can be washed gently and quickly at once.

[0075] A twenty-fifth invention is the sanitary washing apparatus of the twenty-first invention wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

[0076] In this sanitary washing apparatus, the feeling of volume required for bottom washing can be provided, and comfortable bottom washing can be realized. Furthermore, also in terms of the amount of water, a water impinging force can be applied to the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume.

[0077] A twenty-sixth invention is the sanitary washing apparatus of the seventeenth invention further including: water force adjusting means capable of adjusting water impinging force of the water at the human private parts, wherein the water force adjusting means changes timing at which the first water flow group and the second water flow group impinge on the human private parts in accordance with water force specified by a user.

[0078] In this sanitary washing apparatus, within the range of the perception limit frequency, the first water flow group and the second water flow group having mutually different particle diameters are caused to impinge on the human private parts at generally equal timings. This can cause the user to feel that one thick water flow is impinging. Thus, the water impinging force per unit time can be made larger than in the case where the first water flow group and the second water flow group are caused to impinge on the human private parts at mutually different timings. This can cause the user to recognize the water as jetting water having the feeling of volume and as strong jetting water or jetting water providing a feeling of stimulus. Furthermore, even without changing the amount of water supplied to the water force adjusting means, the water force can be adjusted while ensuring the washing power and maintaining the feeling of volume.

[0079]  Furthermore, depending on the difference in the advancement distance of the nozzle, the distance from the jetting hole to the human private parts may be changed. In this context, in this sanitary washing apparatus, the water force adjusting means changes the timings at which the first water flow group and the second water flow group impinge on the human private parts. Thus, even in the case where the distance from the jetting hole to the human private parts is changed, the first water flow group and the second water flow group can be caused to impinge on the human private parts at generally equal timings. This can cause the user to recognize the water as strong jetting water providing the feeling of volume irrespective of the advancement state of the nozzle.

[0080] A twenty-seventh invention is the sanitary washing apparatus of the twenty-sixth invention wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

[0081] In this sanitary washing apparatus, the first water flow group having a larger particle diameter and a faster flow velocity impinges on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, the first water flow group can provide a sufficient feeling of volume or a firm feeling of volume. On the other hand, the second water flow group having a smaller particle diameter and a slower flow velocity impinges on the central part of the human private parts. Thus, while ensuring the washing power, the second water flow group can quickly wash away the dirt in the central part of the human private parts, and gently wash the central part of the human private parts. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. For instance, also for users having hemorrhoids, lacerations, or abrasions due to excessive wipe-up in the human private parts, comfortable bottom washing can be realized.

[0082] A twenty-eighth invention is the sanitary washing apparatus of the twenty-sixth invention wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

[0083] In this sanitary washing apparatus, the feeling of volume required for bottom washing can be provided, and comfortable bottom washing can be realized.

[0084] A twenty-ninth invention is the sanitary washing apparatus of the twenty-sixth invention wherein the first water flow group and the second water flow group are alternately generated from the granulated water flows.

[0085] In this sanitary washing apparatus, as a result, the first water flow group and the second water flow group are alternately jetted from the jetting hole. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Thus, at a small flow rate, the feeling of volume can be provided, and a wide range can be washed gently and quickly at once.

[0086] A thirtieth invention is the sanitary washing apparatus of the twenty-sixth invention wherein the water force adjusting means further includes pulsation generating means configured to provide pulsation to the water jetted from the jetting hole, and changes the timing in accordance with the water force by adjusting period of a voltage pulse applied to the pulsation generating means.

[0087]  In this sanitary washing apparatus, by changing the period of the voltage pulse applied to the pulsation generating means, the water force adjusting means can change the timings at which the first jetting water forming a first water flow group after being fractured and the second jetting water forming a second water flow group after being fractured are jetted from the nozzle. In the case where the on-time of the voltage pulse is constant, the flow velocity of the first water flow group and the flow velocity of the second water flow group are constant. Accordingly, by considering the distance from the jetting hole of the nozzle to the human private parts, and the flow velocity of the first water flow group and the flow velocity of the second water flow group, the water force adjusting means adjusts the period of the voltage pulse for the time from the jetting of the second jetting water until the jetting of the first jetting water. Thus, in accordance with the water force desired by the user, the water force adjusting means can cause the first water flow group and the second water flow group to impinge simultaneously, to impinge at a slight time difference, or to impinge at a longer time difference.

[0088] A thirty-first invention is the sanitary washing apparatus of the twenty-sixth invention wherein the water force adjusting means further includes pulsation generating means configured to provide pulsation to the water jetted from the jetting hole, and changes the timing in accordance with the water force by adjusting on-time of a voltage pulse applied to the pulsation generating means.

[0089] In this sanitary washing apparatus, by changing the on-time of the voltage pulse applied to the pulsation generating means, the water force adjusting means can adjust the flow velocity at which the first jetting water forming a first water flow group after being fractured and the second jetting water forming a second water flow group after being fractured are jetted from the jetting hole. If the water force adjusting means sets the period of the voltage pulse to be constant and makes the on-time of the voltage pulse longer, the flow velocity of the first water flow group is made faster, and the flow velocity of the second water flow group is made slower. On the other hand, if the water force adjusting means sets the period of the voltage pulse to be constant and makes the on-time of the voltage pulse shorter, the flow velocity of the first water flow group is made slower, and the flow velocity of the second water flow group is made faster, although the flow velocity of the first water flow group is not made slower than the flow velocity of the second water flow group. Accordingly, by setting the period of the voltage pulse to be constant, considering the distance from the jetting hole of the nozzle to the human private parts, and the timings at which the first jetting water and the second jetting water are jetted from the jetting hole, and changing the on-time of the voltage pulse, the water force adjusting means adjusts the flow velocity of the first water flow group and the flow velocity of the second water flow group. Thus, in accordance with the water force desired by the user, the water force adjusting means can cause the first water flow group and the second water flow group to impinge simultaneously, to impinge at a slight time difference, or to impinge at a longer time difference.

[0090] The first water flow group and the second water flow group impinge on the human private parts under a condition including the period of the voltage pulse and the on-time of the voltage pulse. If the water force adjusting means adjusts the water force by setting the period of the voltage pulse to be constant and making the on-time of the voltage pulse longer, the flow velocity of the first water flow group is made faster. Thus, the jetting time of the first jetting water can be made longer. This increases the amount of water of the first water flow group. Thus, by making closer the timings at which the first water flow group and the second water flow group impinge on the human private parts, the water force adjusting means can increase the amount of water with the feeling of volume provided by the first water flow group. Accordingly, jetting water providing the feeling of volume to the user can be realized.

[0091] Embodiments of the invention will now be described with reference to the drawings. In the drawings, similar components are labeled with like reference numerals, and the detailed description thereof is omitted appropriately.

[0092] FIG. 1 is a perspective schematic view showing a toilet apparatus equipped with a sanitary washing apparatus according to an embodiment of the invention.

[0093] The toilet apparatus shown in FIG. 1 includes a sit-down toilet stool (hereinafter simply referred to as "toilet stool" for convenience of description) 800 and a sanitary washing apparatus 100 provided thereon. The sanitary washing apparatus 100 includes a casing 400, a toilet seat 200, and a toilet lid 300. The toilet seat 200 and the toilet lid 300 are each pivotally supported on the casing 400 in an openable/closable manner.

[0094] The casing 400 includes therein e.g. a private parts washing functional part for washing the human private parts of a user seated on the toilet seat 200. Furthermore, for instance, the casing 400 includes a seating sensor 404 for sensing seating of a user on the toilet seat 200. When the seating sensor 404 is sensing a user seated on the toilet seat 200, the user can manipulate a manipulator such as a remote control, not shown, to advance a nozzle 410 into the bowl 801 of the toilet stool 800. I n the sanitary washing apparatus 100 shown in FIG. 1, the nozzle 410 is shown in the state of being advanced into the bowl 801.

[0095] One or more jetting holes 411 are provided at the tip of the nozzle 410. The nozzle 410 can squirt water from the jetting hole 410 provided at its tip to wash the human private parts of the user seated on the toilet seat 200. For instance, of the two jetting holes 411 in the nozzle 410 shown in FIG. 1 , one jetting hole 411 is intended for bidet washing, and the other jetting hole 411 is intended for bottom washing. Here, the term "water" used herein refers not only to cold water, but also to heated hot water.

[0096] FIG. 2 is a conceptual schematic view showing a main part configuration of the sanitary washing apparatus according to this embodiment.

[0097] FIG. 3 is a conceptual schematic view generally showing the state of water jetted from the nozzle of this embodiment.

[0098] FIG. 4 is a graph showing an example of impinging water pressure and impinging water amount at the impingement part of the water.

[0099] FIG. 5 is a graph showing another example of impinging water pressure and impinging water amount at the impingement part of the water.

[0100] As described above with reference to FIG. 1 , the nozzle 410 of this embodiment can squirt water 500 from the jetting hole 411 toward the human private parts of the user seated on the toilet seat 200. Here, as shown in FIGS. 2 and 3, the water 500 is jetted from the jetting hole 411 in a hollow conic shape as a liquid film including a hollow portion in the central part. That is, the sanitary washing apparatus 100 according to this embodiment includes a jetting means 410 for jetting water in a hollow conic shape from the jetting hole 411 of the nozzle 410. In the following, for convenience of description, the water jetted in a hollow conic shape in this manner is referred to as "hollow-conic-shape jetting water".

[0101] In the hollow portion of the hollow-conic-shape jetting water 510, the amount of air ejected from the hollow portion of the hollow-conic-shape jetting water 510 to the outside is made larger following the flow of the liquid film. On the other hand, the path of air entering the hollow portion of the hollow-conic-shape jetting water 510 is blocked by the liquid film of the hollow-conic-shape jetting water 510. Thus, the path is limited to the central part of the air ejected from the hollow portion of the hollow-conic-shape jetting water 510 to the outside. This decreases the amount of air entering the hollow portion of the hollow-conic-shape jetting water 510. Thus, the hollow portion of the hollow-conic-shape jetting water 510 is in a negative pressure state in which the pressure is lower than that of the ambient air.

[0102] The sanitary washing apparatus 100 according to this embodiment further includes a fracturing means for fracturing the liquid film of the hollow-conic-shape jetting water 510 so as to fill the hollow portion of the hollow-conic-shape jetting water 510 before the hollow-conic-shape jetting water 510 impinges on the human private parts. That is, as shown in FIG. 3, although described later in detail, the fracturing means generates water flows granulated (hereinafter referred to as "granular water flows" for convenience of description) by fracturing the liquid film of the hollow-conic-shape jetting water 510. Part of the granular water flows 520 traveling in the traveling direction of the liquid film are attracted to the hollow portion by the negative pressure generated in the hollow portion of the hollow-conic-shape jetting water 510. Thus, the fracturing means can fill the hollow portion of the hollow-conic-shape jetting water 510 with the granular water flows 520.

[0103] That is, the water 500 squirted from the nozzle 410 is first jetted from the jetting hole 411 as hollow-conic-shape jetting water 510. Then, with the hollow portion filled with granular water flows 520, the water 500 impinges on a wider range of the human private parts of the user seated on the toilet seat 200.

[0104] Here, as shown in FIG. 2, the sanitary washing apparatus 100 according to this embodiment includes a liquid film thickness expanding means 402 provided on the downstream side of the jetting means 401 and on the upstream side of the jetting hole 411 of the nozzle 410. This liquid film thickness expanding means 402 expands the thickness of the liquid film of the hollow-conic-shape jetting water 510. More specifically, the liquid film thickness expanding means 402 can make the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 411 of the nozzle 410 thicker than the thickness D1 of the liquid film of the hollow-conic-shape jetting water jetted from the jetting means 401. Thus, the diameter of the granular water flow 520 generated by fracturing the liquid film of the hollow-conic-shape jetting water 510 is e.g. approximately 1 mm (millimeter). This is larger than that of spray, which has a diameter of e.g. approximately 10-100 µm (microns).

[0105] The hollow-conic-shape jetting water 510 is fractured by the fracturing means. Then, with the hollow portion filled with the granular water flows 520, the hollow-conic-shape jetting water 510 impinges on the human private parts. As shown in FIG. 4, the impinging water pressure and the impinging water amount at the impingement part of the water 500 are generally equal in the central part and in the outer peripheral part of the impingement part. Alternatively, as shown in FIG. 5, the impinging water pressure and the impinging water amount are larger in the outer peripheral part than in the central part of the impingement part.

[0106] Here, the term "impinging water pressure" used herein refers to the momentum per unit area, representing the power of removing, stripping, or releasing dirt. Alternatively, the term "impinging water pressure" refers to the momentum per unit area at the impingement part or a position separated by a prescribed distance from the jetting hole 411, representing the power of removing, stripping, or releasing dirt.

[0107] The term "impinging water amount" used herein refers to the amount of water impinging per unit time, representing the power of washing dirt away. Alternatively, the term "impinging water amount" refers to the amount of water impinging per unit time at the impingement part or a position separated by a prescribed distance from the jetting hole 411, representing the power of washing dirt away.

[0108] The washing range of the water 500 (washing area at the time of impingement) is e.g. approximately 23-33 mm in diameter. That is, the width of the raised part shown in FIGS. 4 and 5 is equivalent to e.g. approximately 23-33 mm in diameter.

[0109] For instance, in the case of loose stool in bad physical condition, the dirt may be attached over a wide range in four directions. The sanitary washing apparatus 100 according to this embodiment can respond to the demand for washing the wide range quickly at once. Furthermore, the granular water flows 520 filling the hollow portion of the hollow-conic-shape jetting water 510 impinge on the vicinity of the center of the washing area. Thus, the washing pressure in the central part of the washing area is lower than in the case of impingement of the conventional rectilinear flow. Accordingly, there is little danger that strong stimuli are unnecessarily applied to the anal part. Thus, the sanitary washing apparatus 100 according to this embodiment can realize bottom washing with a very comfortable feeling of washing.

[0110] Furthermore, the sanitary washing apparatus 100 according to this embodiment enables water to impinge at once on a wider range than the conventional bottom washing. Thus, there is no need to move the impingement position by moving the nozzle 410 in the front-back direction and left-right direction (see the arrows shown in FIG. 1). Furthermore, there is no need for the user seated on the toilet seat 200 to move the seated position by oneself to move the impingement position. Thus, the sanitary washing apparatus 100 according to this embodiment has little danger of giving a feeling of being swept in washing the human private parts in a wide range. Also for this reason, the sanitary washing apparatus 100 according to this embodiment can realize bottom washing with a very comfortable feeling of washing.

[0111] Furthermore, according to this embodiment, as shown in FIG. 4, the impinging water pressure at the impingement part of the water 500 is generally equal in the central part and in the outer peripheral part of the impingement part. Alternatively, as shown in FIG. 5, the impinging water pressure at the impingement part of the water 500 is higher in the outer peripheral part than in the central part of the impingement part. Here, the outer peripheral part of the desired washing area is an area desired to be actively washed in the case where the dirt is attached over a wide range in four directions due to e.g. loose stool in bad physical condition. The impinging water pressure in the outer peripheral part is generally equal to or higher than the impinging water pressure in the central part. Thus, the water 500 with high washing power impinges on the area where the dirt is to be removed. The water with low impinging water pressure impinges on the anal part. Thus, unnecessarily strong stimuli are not applied thereto. Accordingly, the sanitary washing apparatus 100 according to this embodiment can remove or release more rapidly the dirt attached over a wide range, and realize bottom washing with a very comfortable feeling of washing. Thus, the sanitary washing apparatus 100 according to this embodiment is also suitable as an apparatus used in the case of loose stool in bad physical condition.

[0112]  Furthermore, according to this embodiment, as shown in FIG. 4, the impinging water amount at the impingement part of the water 500 is generally equal in the central part and in the outer peripheral part of the impingement part. Alternatively, as shown in FIG. 5, the impinging water amount at the impingement part of the water 500 is larger in the outer peripheral part than in the central part of the impingement part. Here, as described above, the outer peripheral part of the desired washing area is an area desired to be actively washed in the case where the dirt is attached over a wide range in four directions due to e.g. loose stool in bad physical condition. The impinging water amount in the outer peripheral part is generally equal to or larger than the impinging water amount in the central part. Thus, a sufficient amount of water 500 impinges on the area where the dirt is to be removed. On the other hand, the water with a small impinging water amount impinges on the anal part. This can suppress discomfort due to washing with an unnecessarily large amount of water. Thus, the dirt attached over a wide range is captured more reliably by the impinging water 500, and washed away more rapidly. Furthermore, bottom washing with a very comfortable feeling of washing can be realized. Thus, as described above, the sanitary washing apparatus 100 according to this embodiment is also suitable as an apparatus used in the case of loose stool in bad physical condition.

[0113] Next, an example of this embodiment is described with reference to the drawings.

[0114] FIG. 6 is a sectional schematic view showing a nozzle according to the example of this embodiment.

[0115] FIG. 7 is a sectional schematic view showing a nozzle according to a comparative example.

[0116] FIG. 8 is a sectional schematic view illustrating a variation of the throat.

[0117] As shown in FIG. 6, the nozzle 410 of this example includes a nozzle body (jetting means) 420 and a throat (liquid film thickness expanding means and annular part) 430. The nozzle body 420 includes therein a nozzle body flow channel 421 for passing water supplied from a water source, not shown, a swirling chamber 423 capable of generating a swirling flow, and a communication channel 425 for guiding water from the swirling chamber 423 to the throat 430. At the center of the swirling chamber 423, a protrusion 424 for generating a swirling flow with stabler swirling power is provided.

[0118] The swirling chamber 423 is a hollow chamber formed from a large diameter inner peripheral wall 423e having a larger diameter at the bottom, and an inclined inner peripheral wall 423f having a diameter shrinking toward the communication channel 425. At one end of the inclined inner peripheral wall 423f, the inclined inner peripheral wall 423f is connected to the communication channel 425. On the other hand, the nozzle body flow channel 421 is connected eccentrically to the swirling chamber 423. More specifically, the nozzle body flow channel 421 is connected in the tangential direction of the large diameter inner peripheral wall 423e of the swirling chamber 423.

[0119] The throat 430 is formed in a tubular shape. The throat 430 includes therein a throat flow channel 431 for passing water jetted from the communication channel 425 of the nozzle body 420. Furthermore, a jetting hole 433 (jetting hole) is formed at one end of the throat flow channel 431. The jetting hole 433 is configured so that the water passed through the throat flow channel 431 is jetted outside the throat 430. The throat flow channel 431 near the jetting hole 433 includes a taper part 432 having a flow channel expanding toward the jetting hole 433.

[0120] In the nozzle 410 of this example, a gap is provided between the nozzle body 420 and the throat 430. However, this gap does not necessarily need to be provided. That is, the nozzle body 420 and the throat 430 may be integrally formed so that the communication channel 425 and the throat flow channel 431 are connected.

[0121] When water is supplied to the nozzle 410 from a water source, not shown, the water passes through the nozzle body flow channel 421 and flows into the swirling chamber 423. Here, the nozzle body flow channel 421 is connected in the tangential direction of the large diameter inner peripheral wall 423e of the swirling chamber 423. Thus, the water poured into the swirling chamber 423 swirls along the large diameter inner peripheral wall 423e and the inclined inner peripheral wall 423f. Then, the water swirled in the swirling chamber 423 passes through the communication channel 425 while maintaining the swirling power, and is jetted from one end (jetting port) of the communication channel 425 into the throat flow channel 431 of the throat 430. At this time, the water jetted from the nozzle body 420 maintains the swirling power. Thus, the water is jetted in a hollow conic shape as a liquid film including a hollow portion in the central part.

[0122] The water jetted in the hollow conic shape from the nozzle body 420 is received by the inner wall of the throat flow channel 431. Then, the water poured into the throat flow channel 431 flows along the inner wall of the throat flow channel 431 while maintaining the swirling power, and is guided to the jetting hole 433. That is, the water passing through the throat flow channel 431 flows in contact with the inner wall of the throat flow channel 431. Thus, the water flowing in the throat flow channel 431 is subjected to resistance due to the frictional force from the inner wall of the throat flow channel 431. The flow velocity of the water is slowed down toward the jetting hole 433. Thus, as shown in FIG. 6, the thickness of the liquid film near the jetting hole 433 is thicker than the thickness of the liquid film jetted from the nozzle body 420, or the thickness of the liquid film just poured into the throat flow channel 431. I n other words, the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 is thicker than the thickness D1 of the liquid film of the hollow-conic-shape jetting water jetted from the nozzle body 420. That is, in this example, the nozzle body 420 functions as the jetting means 401 described above with reference to FIG. 2.

[0123] Furthermore, the flow velocity of the water flowing in the throat flow channel 431 is faster in the central part of the throat flow channel 431 than near the inner wall, i.e., in the boundary layer, of the throat flow channel 431. That is, the throat 430 can produce a difference between the flow velocity of the water flowing near the inner wall of the throat flow channel 431 and the flow velocity of the water flowing on the central part side of the neighborhood of the inner wall of the throat flow channel 431. I n other words, the throat 430 can produce a velocity difference between the flow outside (on the inner wall side of the throat flow channel 431) the liquid film of the water and the flow inside (on the central part side of the throat flow channel 431) the liquid film of the water. This is because the water outside (on the inner wall side of the throat flow channel 431) the liquid film is subjected to a larger frictional force from the inner wall of the throat flow channel 431 than the water inside (on the central part side of the throat flow channel 431) the liquid film. Thus, the outside water is further decelerated than the inside water.

[0124] Thus, inside the water flowing in the throat flow channel 431, as indicated by arrow A1 shown in FIG. 6, vortices are generated in a direction traversing the liquid film. Furthermore, in the throat flow channel 431 near the jetting hole 433, the taper part 432 having a flow channel expanding toward the jetting hole 433 is formed. Thus, the water jetted from the jetting hole 433 flows along the taper part 432. Accordingly, inside the water jetted from the jetting hole 433, vortices are more likely to occur in a direction traversing the liquid film.

[0125] Then, the water jetted from the jetting hole 433 is jetted as a liquid film including a hollow portion in the central part, i.e., as hollow-conic-shape jetting water 510, and transitions to granular water flows 520 at a position spaced to some extent from the jetting hole 433. More specifically, inside the hollow-conic-shape jetting water 510 jetted from the jetting hole 433, vortices are generated in a direction traversing the liquid film. Thus, at a position spaced to some extent from the jetting hole 433, a crack occurs between adjacent vortices. Accordingly, as shown in FIG. 6, the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 is fractured at a position spaced to some extent from the jetting hole 433. Thus, the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 transitions to granular water flows 520. That is, the throat 430 of this example also functions as a fracturing means in addition to functioning as a liquid film thickness expanding means 402.

[0126] The pressure in the hollow portion of the hollow-conic-shape jetting water 510 is lower than the pressure outside the hollow-conic-shape jetting water 510. The reason for this is as follows. Air is less likely to enter the hollow portion of the hollow-conic-shape jetting water 510 from outside. Furthermore, the air in the hollow portion is drawn out by the flow of the hollow-conic-shape jetting water 510. Thus, the pressure in the hollow portion of the hollow-conic-shape jetting water 510 is lower than the pressure outside the hollow-conic-shape jetting water 510. This suppresses expansion of the jetting water diameter (cone diameter) of the hollow-conic-shape jetting water 510.

[0127] Thus, the nozzle 410 of this example can suppress impingement of the granular water flows 520 outside the washing area. Accordingly, unnecessary wetting of the portion (e.g., thigh) outside the desired washing area can be suppressed. This can suppress discomfort felt by the user seated on the toilet seat 200 due to unnecessary wetting of the portion outside the desired washing area.

[0128] Furthermore, as described above with reference to FIG. 2, the granular water flow 520 has a diameter of e.g. approximately 1 mm, larger than that of spray, which has a diameter of e.g. approximately 10-100 µm. This is because as described above, the flow velocity of water flowing in the throat flow channel 431 is slowed down toward the jetting hole 433, thus thickening the thickness of the liquid film near the jetting hole 433. That is, the hollow-conic-shape jetting water 510 jetted with a thicker liquid film is forcibly granulated by vortices generated inside the throat 430. Thus, the granular water flow 520 has a larger diameter than spray and the like.

[0129] Furthermore, the flow velocity of water flowing in the throat flow channel 431 is slowed down toward the jetting hole 433. Thus, the throat 430 can averagely expand the thickness of the liquid film of the water flowing in the throat flow channel 431. Accordingly, the throat 430 can prevent more reliably the generation of particles having a smaller diameter due to variation in the thickness of the liquid film. Furthermore, the throat 430 receives the water jetted from the nozzle body 420 at the inner wall of the throat flow channel 431. Thus, the throat 430 can receive the impact of the water uniformly in the circumferential direction. Accordingly, the throat 430 can expand the thickness of the liquid film in the state of smaller variation in the circumferential direction of the water and jet the water from the jetting hole 433. Thus, the throat 430 can prevent more reliably the generation of particles having a smaller diameter due to variation in the thickness of the liquid film.

[0130]  Thus, there is little danger that the granular water flows 520 drift in the air. Accordingly, there is little danger that the granular water flows 520 scatter to the outside of the desired washing area. That is, the nozzle 410 of this example can suppress impingement of the granular water flows 520 outside the washing area, and can suppress unnecessary wetting of the portion outside the desired washing area. Furthermore, because of the larger diameter of the granular water flow 520, the impinging water pressure and impinging water amount at the impingement part can be made higher. Thus, for instance, the dirt attached over a wide range in four directions due to e.g. loose stool in bad physical condition can be removed or released more rapidly, and washed away more rapidly.

[0131] As described above, the pressure in the hollow portion of the hollow-conic-shape jetting water 510 is lower than the pressure outside the hollow-conic-shape jetting water 510. This pressure in the hollow portion of the hollow-conic-shape jetting water 510 is higher than the pressure in the hollow portion of the hollow-conic-shape jetting water 510 not fractured. This is because as indicated by arrow A2 shown in FIG. 6, air outside the hollow portion of the hollow-conic-shape jetting water 510 enters the hollow portion through a crack generated between adjacent vortices. This can suppress the danger that a sufficiently wide washing range cannot be ensured due to excessive decrease of pressure in the hollow portion of the hollow-conic-shape jetting water 510. Furthermore, because the pressure in the hollow portion of the hollow-conic-shape jetting water 510 is higher than the pressure in the hollow portion of the hollow-conic-shape jetting water 510 not fractured, the occurrence of liquid film rippling can be suppressed.

[0132] Here, liquid film rippling is described with reference to the comparative example shown in FIG. 7.

[0133] The nozzle of the comparative example shown in FIG. 7 includes no throat. Thus, the water poured into the swirling chamber 423 swirls along the large diameter inner peripheral wall 423e and the inclined inner peripheral wall 423f, passes through the communication channel 425, and is jetted as a liquid film including a hollow portion in the central part, i.e., as hollow-conic-shape jetting water 510. That is, in the nozzle of this comparative example, one end of the communication channel 425 functions as a jetting hole 426.

[0134] Here, the flow velocity of the water passing through the communication channel 425 of this comparative example is not made so slow as the flow velocity of the water flowing in the throat flow channel 431 of the example shown in FIG. 6. Thus, the thickness of the liquid film of the water passing through the communication channel 425 of this comparative example is thinner than the thickness of the liquid film of the water flowing in the throat flow channel 431 of the example shown in FIG. 6. Furthermore, because the thickness of the liquid film of the water passing through the communication channel 425 of this comparative example is thinner, vortices are less likely to occur in a direction traversing the liquid film inside the water. Thus, the hollow-conic-shape jetting water 510 jetted from the jetting hole 426 of this comparative example is less likely to be fractured than in the example shown in FIG. 6.

[0135] Thus, the hollow-conic-shape jetting water 510 continues to expand while remaining the liquid film without being fractured. With the expansion of the jetting water diameter of the hollow-conic-shape jetting water 510, the thickness of the liquid film becomes thinner. Thus, the liquid film of the hollow-conic-shape jetting water 510 becomes more susceptible to the pressure difference between the hollow portion of the hollow-conic-shape jetting water 510 and the portion outside the hollow-conic-shape jetting water 510.

[0136] Thus, as shown in FIG. 7, due to the pressure difference between the hollow portion of the hollow-conic-shape jetting water 510 and the portion outside the hollow-conic-shape jetting water 510, the hollow-conic-shape jetting water 510 at a position spaced to some extent from the jetting hole 426 experiences a phenomenon like rippling while retaining the state of the liquid film. In this specification, such a phenomenon is referred to as "liquid film rippling".

[0137] If the liquid film of the hollow-conic-shape jetting water 510 is fractured after liquid film rippling occurs, the fractured and granulated water flows scatter in irregular directions due to the effect of rippling. Thus, the water is likely to scatter to the outside of the desired washing area. Then, the scattered water is attached to the thigh and the like of the user seated on the toilet seat 200, and the user may feel discomfort.

[0138] Liquid film rippling occurs at a position where the thickness of the liquid film is thinned. Furthermore, the occurrence of rippling further elongates the trajectory of the liquid film. Thus, the thickness of the liquid film becomes thinner. That is, if liquid film rippling occurs in the hollow-conic-shape jetting water 510, the hollow-conic-shape jetting water 510 is fractured into particles having a smaller diameter than the granular water flow 520 shown in FIG. 6. This fractured particle has a small diameter and mass. Thus, the small particle drifts in the air, and is likely to scatter to the outside of the desired washing area. Then, the scattered water is attached to the thigh and the like of the user seated on the toilet seat 200, and the user may feel discomfort.

[0139] In contrast, in the nozzle 410 according to this example, the thickness of the liquid film near the jetting hole 433 is larger than the thickness of the liquid film jetted from the nozzle body 420, or the thickness of the liquid film just poured into the throat flow channel 431. I n other words, the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 is thicker than the thickness D1 of the liquid film of the hollow-conic-shape jetting water jetted from the nozzle body 420. Thus, inside the water jetted from the jetting hole 433, vortices are more likely to occur in a direction traversing the liquid film. Accordingly, the hollow-conic-shape jetting water 510 is more likely to be fractured, and air is more likely to enter the hollow portion thereof. This can prevent the pressure in the hollow portion of the hollow-conic-shape jetting water 510 from decreasing. Thus, the occurrence of liquid film rippling in the hollow-conic-shape jetting water 510 can be suppressed.

[0140] This can suppress scattering of the granulated water flows in irregular directions due to the effect of rippling, and scattering of water to the outside of the desired washing area. Furthermore, unnecessary wetting of the portion outside the desired washing area can be suppressed. Furthermore, fracturing of the hollow-conic-shape jetting water 510 into particles having a smaller diameter can be suppressed. That is, in order to prevent the occurrence of liquid film rippling, or before the occurrence of liquid film rippling, the hollow-conic-shape jetting water 510 jetted with a thicker liquid film is forcibly fractured and granulated by vortices generated inside the throat 430. Thus, the diameter of the granular water flow 520 can be made larger. Accordingly, scattering of water to the outside of the desired washing area can be suppressed, and unnecessary wetting of the portion outside the desired washing area can be suppressed. This can suppress that the user seated on the toilet seat 200 feels discomfort due to unnecessary wetting of the portion outside the desired washing area.

[0141] Furthermore, because the occurrence of liquid film rippling in the hollow-conic-shape jetting water 510 can be suppressed, excessive decrease of pressure in the hollow portion of the hollow-conic-shape jetting water 510 can be suppressed. Thus, with the hollow portion of the hollow-conic-shape jetting water 510 filled with granular water flows 520, water can be caused to impinge on a wider range of the human private parts of the user seated on the toilet seat 200. Accordingly, the desired wide range can be washed quickly at once.

[0142] Furthermore, in the nozzle 410 of this example, a gap is provided between the nozzle body 420 and the throat 430. That is, the portion between the nozzle body (jetting means) 420 and the throat (liquid film thickness expanding means) 430 is opened to the atmosphere. Thus, the occurrence of negative pressure between the outer peripheral side of the liquid film of the water jetted in the hollow conic shape from the nozzle body 420 and the inner wall of the throat flow channel 431 can be suppressed. This can suppress that the liquid film of the water jetted in the hollow conic shape from the nozzle body 420 is granulated inside the throat 430 by being pulled by the negative pressure and placed in an unstable state. That is, the state of the liquid film can be maintained inside the throat 430, and the thickness of the liquid film can be expanded more reliably.

[0143] In the variation shown in FIG. 8, a spiral groove 435 is formed on the inner wall of the throat flow channel. In this case, the water flowing in the throat flow channel is subjected to larger resistance from the spiral groove 435. More specifically, the water flowing in the throat flow channel is subjected to larger resistance on the outflow side (the side of the jetting hole 433) of the throat flow channel than on the inflow side (the side of the communication channel 425 of the nozzle body 420) of the throat flow channel. Thus, in the water flowing in the throat flow channel, the swirling component of the velocity of the water flowing in the throat flow channel is maintained, but the rectilinear component of the velocity is decelerated.

[0144]  Thus, the water poured into the throat flow channel is gradually decelerated on the inflow side of the throat flow channel, and sharply decelerated on the outflow side of the throat flow channel. This can suppress that the water jetted from the nozzle body 420 and poured into the throat flow channel is granulated under large resistance or impact when the velocity is faster. Thus, in this variation, while maintaining the water flowing inside the throat flow channel in the state of the liquid film, the water can be decelerated more stably. Accordingly, the thickness of the liquid film can be expanded more reliably.

[0145] Furthermore, the time of contact between the water flowing in the throat flow channel and the spiral groove 435 is longer than in the case without the spiral groove 435. Thus, in this variation, the water flowing in the throat flow channel is subjected to the frictional force from the spiral groove 435 over a longer time than in the case without the spiral groove 435. Accordingly, the velocity difference between the flow outside (on the inner wall side of the throat flow channel) the liquid film of the water and the flow inside (on the central part side of the throat flow channel) the liquid film of the water is larger than in the case without the spiral groove 435.

[0146] Thus, the thickness of the liquid film of the water flowing in the throat flow channel of this variation is thicker than the thickness of the liquid film of the water flowing in the throat flow channel 431 of the example shown in FIG. 6. That is, by forming a spiral groove 435 on the inner wall of the throat flow channel, the thickness of the liquid film near the jetting hole 433, or the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 433, can be made thicker.

[0147] Thus, in this variation, the generation of particles having a smaller diameter can be prevented more reliably, and the diameter of the granular water flow 520 can be made larger. Accordingly, scattering of water to the outside of the desired washing area can be suppressed more reliably. Furthermore, unnecessary wetting of the portion outside the desired washing area can be suppressed. This can suppress that the user seated on the toilet seat 200 feels discomfort due to unnecessary wetting of the portion outside the desired washing area.

[0148] FIG. 9 is a sectional schematic view showing a nozzle according to an alternative example of this embodiment.

[0149] FIG. 10 is a graph showing the timing of driving the pulsation pump and the velocity of the liquid film of this example.

[0150] FIGS. 11 and 12 are schematic sectional views illustrating the state of the granular water flows of interval a-b in FIG. 10.

[0151] FIGS. 13 and 14 are schematic sectional views illustrating the state of the granular water flows of interval c-d in FIG. 10.

[0152] FIG. 15 is a schematic sectional view showing the state of the granular water flows at the bottom impingement location of this example. FIG. 16 is a graph showing the spatial density of the granular water flows at the bottom impingement location of this example.

[0153] Like the nozzle 410 of the example described above with reference to FIG. 6, the nozzle 410 according to this example includes a nozzle body 420. The water poured into the swirling chamber 423 swirls in the swirling chamber 423, passes through the communication channel 425, and is jetted as a liquid film including a hollow portion in the central part, i.e., as hollow-conic-shape jetting water 510, from the jetting hole 426 to the outside of the nozzle body 420.

[0154] Furthermore, the sanitary washing apparatus 100 equipped with the nozzle 410 according to this example includes a pulsation pump (pulsation generating means) 470 in midstream of the nozzle body flow channel 421. The pulsation pump 470 can modulate the pressure of water in the nozzle body flow channel 421. This pulsation pump 470 applies pulsation to the flow of water in the nozzle body flow channel 421. Thus, the pulsation pump 470 can apply pulsation to the water jetted from the jetting hole 426. The remaining structure is similar to the structure of the nozzle 410 according to the example described above with reference to FIG. 6.

[0155] Next, the relationship between the timing of driving the pulsation pump 470 and the velocity of the liquid film of this example is described with reference to FIG. 10.

[0156] As shown in FIG. 10, the pulsation pump is alternately placed in the state of high and low pressure modulation force. Then, the liquid film velocity tends to decrease in the interval a-b, and tends to increase in the interval c-d. More specifically, in the interval a-b, because the liquid film velocity tends to decrease, the liquid film velocity becomes faster as the liquid film forming the hollow-conic-shape jetting water 510 shown in FIG. 9 is distanced from the jetting hole 426. Conversely, in the interval c-d, because the liquid film velocity tends to increase, the liquid film velocity becomes slower as the liquid film forming the hollow-conic-shape jetting water 510 shown in FIG. 9 is distanced from the jetting hole 426.

[0157] The granular water flows associated with the variation in the pressure modulation force of the pulsation pump are now described with reference to FIGS. 11 to 14. FIG. 11 is a schematic sectional view illustrating the state of the granular water flows in the initial phase of the interval a-b in FIG. 10. FIG. 12 is a schematic sectional view illustrating the state of the granular water flows in the last phase of the interval a-b in FIG. 10. FIG. 13 is a schematic sectional view illustrating the state of the granular water flows in the initial phase of the interval c-d in FIG. 10. FIG. 14 is a schematic sectional view illustrating the state of the granular water flows in the last phase of the interval c-d in FIG. 10.

[0158] As described above with reference to FIG. 10, in the interval a-b, the liquid film velocity becomes faster as the liquid film is distanced from the jetting hole 426. In other words, in the liquid film, at a position nearer to the jetting hole, the velocity of the water flow forming the liquid film at that position is slower. Thus, the internal flow velocity difference of the liquid film is produced so that a large flow velocity difference occurs between the tip of the liquid film farthest from the jetting hole and the root of the liquid film nearest to the jetting hole. Due to this flow velocity difference in the liquid film, the liquid film is placed in a thinly stretched state. As a result, in the initial phase of the interval a-b, as shown in FIG. 11, the hollow-conic-shape jetting water 510 is fractured by the fracturing means at the position of solid line B farther from the jetting hole 426 than the position of dotted line A where there is no pressure modulation by the pulsation pump. The position of solid line B is separated by distance d from the jetting hole 426. The hollow-conic-shape jetting water 510 having a thin thickness of the liquid film is turned to granular water flows in the state of fast liquid film velocity at the position far from the jetting hole 426. In the granular water flows thus formed, the particle diameter of the liquid drop is small, and the velocity is fast.

[0159] As shown in FIG. 12, in the last phase of the interval a-b, i.e., in the time zone near b, the hollow-conic-shape jetting water 510 is fractured by the fracturing means at the position of solid line C nearer to the jetting hole 426 than the position of solid line B shown in FIG. 11. The position of solid line C is located at distance d smaller than the distance d of FIG. 11. In the hollow-conic-shape jetting water 510, the liquid film thickness is thin, and furthermore, the length is also decreased. This hollow-conic-shape jetting water 510 is turned to granular water flows in the state of slow liquid film velocity at the position near the jetting hole 426. In the granular water flows thus formed, the particle diameter of the liquid drop is small like the granular water flows formed in the initial phase of the interval a-b of FIG. 11, but the velocity is slow.

[0160] Next, the state of the granular water flows of the interval c-d in FIG. 10 is described. I n the interval c-d, the liquid film velocity becomes slower as the liquid film is distanced from the jetting hole 426. I n other words, in the liquid film, at a position nearer to the jetting hole, the velocity of the water flow forming the liquid film at that position is faster. Thus, an internal flow velocity difference of the liquid film totally opposite to the interval a-b is produced. By this production of the internal flow velocity difference opposite to the interval a-b, the thickness of the liquid film is increased from the jetting hole 426 side. Here, promotion of fracturing by the internal flow velocity difference of the liquid film is added to the fracturing of the hollow-conic-shape jetting water 510 by the fracturing means. Thus, the liquid film is torn off at the position of solid line D separated by distance d from the jetting hole 426 shown in FIG. 13. Accordingly, granular water flows are generated. The hollow-conic-shape jetting water 510 having a thick liquid film thickness is turned to granular water flows in the state of slow liquid film velocity at the position near the jetting hole 426. In the granular water flows thus formed, the particle diameter of the liquid drop is large, and the velocity is fast.

[0161] This phenomenon gradually proceeds from the jetting hole 426 side. However, toward d of the interval c-d, i.e., as the flow velocity becomes higher, the site of production of the granular water flows is distanced from the jetting hole 426. Specifically, in the time zone near d of the interval c-d, as shown in FIG. 14, granular water flows are generated at the position of solid line E further separated by distance d from the jetting hole 426 than the dotted line A where there is no pressure modulation by the pulsation pump. In the hollow-conic-shape jetting water 510, the liquid film thickness is thick, and furthermore, the length is also increased. This hollow-conic-shape jetting water 510 is turned to granular water flows in the state of fast liquid film velocity at the position far from the jetting hole 426. I n the granular water flows thus formed, the particle diameter of the liquid drop is large like the granular water flow formed in the initial phase of the interval c-d of FIG. 13, but the velocity is fast.

[0162] As a result, granular water flows are formed by application of pressure modulation by the pulsation pump. At the time of fracturing of the hollow-conic-shape jetting water 510 by the fracturing means, the fracturing position of the hollow-conic-shape jetting water 510 is changed. In the jetting range, around the center, granular water flows with a slow flow velocity are dominant. Around the periphery, granular water flows with a fast flow velocity are dominant. As shown in FIG. 15, this velocity difference may be controlled so that the slow granular water flows and the granular water flows with a fast flow velocity simultaneously impinge on the bottom. Then, as shown in FIG. 16, the spatial density of the granular water flows at the bottom impingement location can be increased. Furthermore, due to the velocity difference of the granular water flows, a subsequently formed liquid drop with a fast velocity collides with a previously formed liquid drop with a slow velocity. Then, the liquid drops are united into a liquid drop having a larger volume. Thus, the washing area can be washed gently and quickly at once by uniform impingement of water on a wider range than the conventional bottom washing. Furthermore, a high feeling of water volume required for the act of bottom washing can be realized.

[0163] Next, an alternative embodiment of this invention is described.

[0164] FIG. 17 is a conceptual schematic view showing a main part configuration of a sanitary washing apparatus according to the alternative embodiment of this invention.

[0165] FIGS. 18A to 19 are conceptual schematic views generally showing the state of water jetted from the nozzle of this embodiment.

[0166] Here, FIG. 19 is a conceptual schematic view generally showing the state of water at the impingement position as viewed in the direction of arrow A15 shown in FIGS. 18A and 18B.

[0167] The toilet apparatus equipped with the sanitary washing apparatus according to this embodiment is similar to the toilet apparatus described above with reference to FIG. 1.

[0168] As described above with reference to FIG. 1, the nozzle 410 of this embodiment can squirt water 500 from the jetting hole 411 toward the human private parts of the user seated on the toilet seat 200. Here, as shown in FIG. 17, the water 500 is jetted from the jetting hole 411 in a hollow conic shape as a liquid film including a hollow portion in the central part. That is, the sanitary washing apparatus 100 according to this embodiment includes a jetting means 410 for jetting water in a hollow conic shape from the jetting hole 411 of the nozzle 410. In the following, for convenience of description, the water jetted in a hollow conic shape in this manner is referred to as "hollow-conic-shape jetting water".

[0169] In the hollow portion of the hollow-conic-shape jetting water 510, the amount of air ejected from the hollow portion of the hollow-conic-shape jetting water 510 to the outside is made larger following the flow of the liquid film. On the other hand, the path of air entering the hollow portion of the hollow-conic-shape jetting water 510 is blocked by the liquid film of the hollow-conic-shape jetting water 510. Thus, the path is limited to the central part of the air ejected from the hollow portion of the hollow-conic-shape jetting water 510 to the outside. This decreases the amount of air entering the hollow portion of the hollow-conic-shape jetting water 510. Thus, the hollow portion of the hollow-conic-shape jetting water 510 is in a negative pressure state in which the pressure is lower than that of the ambient air.

[0170] The sanitary washing apparatus 100 according to this embodiment further includes a fracturing means for fracturing the liquid film of the hollow-conic-shape jetting water 510 so as to fill the hollow portion of the hollow-conic-shape jetting water 510 before the hollow-conic-shape jetting water 510 impinges on the human private parts. That is, as shown in FIG. 17, although described later in detail, the fracturing means generates water flows granulated (hereinafter referred to as "granular water flows" for convenience of description) by fracturing the liquid film of the hollow-conic-shape jetting water 510. Part of the granular water flows 520 traveling in the traveling direction of the liquid film flow into the hollow portion by the negative pressure generated in the hollow portion of the hollow-conic-shape jetting water 510. Thus, the fracturing means can fill the hollow portion of the hollow-conic-shape jetting water 510 with the granular water flows 520.

[0171] That is, in FIG. 1 , the water 500 squirted from the nozzle 410 is first jetted from the jetting hole 411 as hollow-conic-shape jetting water 510. Then, with the hollow portion filled with granular water flows 520, the water 500 can impinge on a wider range of the human private parts of the user seated on the toilet seat 200.

[0172] As shown in FIG. 17, the sanitary washing apparatus 100 according to this embodiment includes a liquid film thickness expanding means 402 provided on the downstream side of the jetting means 401 and on the upstream side of the jetting hole 411 of the nozzle 410. This liquid film thickness expanding means 402 expands the thickness of the liquid film of the hollow-conic-shape jetting water 510. More specifically, the liquid film thickness expanding means 402 can make the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 411 of the nozzle 410 thicker than the thickness D1 of the liquid film of the hollow-conic-shape jetting water jetted from the jetting means 401. Thus, the diameter of the granular water flow 520 generated by fracturing the liquid film of the hollow-conic-shape jetting water 510 is e.g. approximately 1 mm (millimeter). This is larger than that of spray, which has a diameter of e.g. approximately 10-100 µm (microns).

[0173] As shown in FIGS. 18A and 18B, the water 500 squirted from the nozzle 410 includes first jetting water 501 and second jetting water 502. That is, the nozzle 410 is configured to consequently jet first jetting water 501 and second jetting water 502. The first jetting water 501 and the second jetting water 502 are alternately jetted from the nozzle 410. The flow velocity of the first jetting water 501 is faster than the flow velocity of the second jetting water 502. In other words, the flow velocity of the second jetting water 502 is slower than the flow velocity of the first jetting water 501. That is, in the sanitary washing apparatus 100 according to this embodiment, the first jetting water 501 having a faster flow velocity than the second jetting water 502, and the second jetting water 502 having a slower flow velocity than the first jetting water 501, are generated.

[0174] As shown in FIG. 18A, the first jetting water 501 is jetted from the jetting hole 411 as first hollow-conic-shape jetting water 511. Before impingement, the first hollow-conic-shape jetting water 511 is fractured into first granular water flows 521. Then, a plurality of first granular water flows 521 form a first water flow group 521 a.

[0175] As shown in FIG. 18B, the second jetting water 502 is jetted from the jetting hole 411 as second hollow-conic-shape jetting water 512. Before impingement, the second hollow-conic-shape jetting water 512 is fractured into second granular water flows 522. Then, a plurality of second granular water flows 522 form a second water flow group 522a.

[0176] That is, the hollow-conic-shape jetting water 510 includes first hollow-conic-shape jetting water 511 and second hollow-conic-shape jetting water 512. The granular water flows 520 include first granular water flows 521 and second granular water flows 522. The first water flow group 521 a and the second water flow group 522a are alternately jetted.

[0177] The flow velocity of the first jetting water 501 is faster than the flow velocity of the second jetting water 502. Thus, the thickness of the liquid film of the first hollow-conic-shape jetting water 511 is thicker than the thickness of the liquid film of the second hollow-conic-shape jetting water 512. Furthermore, the length of the liquid film of the first hollow-conic-shape jetting water 511 is longer than the length of the liquid film of the second hollow-conic-shape jetting water 512. That is, the liquid film of the first hollow-conic-shape jetting water 511 is fractured into first granular water flows 521 in a thicker and longer state than the liquid film of the second hollow-conic-shape jetting water 512. Thus, the first granular water flows 521 have a larger particle diameter and a faster flow velocity than the second granular water flows 522.

[0178] As described above, the liquid film of the first hollow-conic-shape jetting water 511 is fractured in a longer state, i.e., at a position farther from the jetting hole 41 1 , than the liquid film of the second hollow-conic-shape jetting water 512. Thus, the liquid film of the first hollow-conic-shape jetting water 511 is fractured in a more spread state than the liquid film of the second hollow-conic-shape jetting water 512. Accordingly, as shown in FIG. 18A, the first granular water flows 521 impinge on the outer peripheral part of the human private parts with a larger particle diameter and a faster flow velocity than the second granular water flows 522. Furthermore, most of the first granular water flows 521 impinge before filling the hollow portion. Thus, as indicated by arrow A11 and arrow A12 shown in FIG. 18A, the first jetting water 501 impinges on the outer peripheral part of the human private parts as the first granular water flows 521, and includes a flow toward the central part of the human private parts.

[0179] On the other hand, the second jetting water 502 has an action opposite to the first jetting water 501. That is, the liquid film of the second hollow-conic-shape jetting water 512 is fractured into second granular water flows 522 in a thinner and shorter state than the liquid film of the first hollow-conic-shape jetting water 511. Thus, the second granular water flows 522 have a smaller particle diameter and a slower flow velocity than the first granular water flows 521.

[0180] Furthermore, the liquid film of the second hollow-conic-shape jetting water 512 is fractured in a less spread state than the liquid film of the first hollow-conic-shape jetting water 51 1 . Accordingly, as shown in FIG. 18B, the second granular water flows 522 impinge on the central part of the human private parts with a smaller particle diameter and a slower flow velocity than the first granular water flows 521. Furthermore, the second granular water flows 522 impinge while filling the hollow portion. Thus, as indicated by arrow A13 and arrow A14 shown in FIG. 18B, the second jetting water 502 impinges on the central part of the human private parts as the second granular water flows 522, and includes a flow toward the outer peripheral part of the human private parts.

[0181] As described later in detail, the impinging water force at the human private parts of the first jetting water 501 is larger than the impinging water force at the human private parts of the second jetting water 502.

[0182]  Here, the term "impinging water force" used herein refers to at least one of the impinging water flow velocity, the impinging water amount, and the impinging water pressure of the water 500, and refers to the momentum of the water per unit area per unit time, representing the power of removing, stripping, or releasing dirt. The term "impinging water flow velocity" refers to the flow velocity of the water 500 at the impingement part or a position separated by a prescribed distance from the jetting hole 411.

[0183] Thus, the first jetting water 501 has a larger particle diameter and a faster flow velocity than the second jetting water 502. Accordingly, the impinging water amount of the first jetting water 501 is larger than the impinging water amount of the second jetting water 502. The impinging water flow velocity of the first jetting water 501 is faster than the impinging water flow velocity of the second jetting water 502. The impinging water force of the first jetting water 501 is larger than the impinging water force of the second jetting water 502. As a result, the first jetting water 501 can provide a higher feeling of volume than the second jetting water 502. Furthermore, a higher washing power can be ensured by the flow of the first jetting water 501 after impinging on the human private parts and the flow of the second jetting water 502 after impinging on the human private parts. Here, the term "feeling of volume" used herein refers to the skin sensation at the time when a thick water flow with a plentiful water amount impinges on the skin surface, or the feeling of washing away dirt with a large flow rate. Even if the physical amount of jetting water decreases, the "feeling of volume" is assumed to be the same as long as the function and effect of the jetting water exerted on the sensory organs scattered in the skin surface portion of the human body. Furthermore, the water 500 squirted from the nozzle 410 includes the first jetting water 501 and second jetting water 502. Thus, the water 500 can provide the feeling of volume at a small flow rate, and can gently wash the human private parts with the granular water flows 521, 522 while reliably ensuring the washing power.

[0184] The fracturing position of the liquid film of the hollow-conic-shape jetting water 510 is periodically varied. For instance, as a result, the first jetting water 501 and the second jetting water 502 are alternately jetted from the nozzle 410. As described above, the liquid film of the first hollow-conic-shape jetting water 511 is fractured in a longer state, i.e., at a position farther from the jetting hole 41 1 , than the liquid film of the second hollow-conic-shape jetting water 512. On the other hand, the liquid film of the second hollow-conic-shape jetting water 512 is fractured in a shorter state, i.e., at a position nearer to the jetting hole 41 1 , than the liquid film of the first hollow-conic-shape jetting water 511. Thus, the fracturing position of the liquid film of the hollow-conic-shape jetting water 510 is periodically varied.

[0185] The means for periodically varying the fracturing position of the liquid film of the hollow-conic-shape jetting water 510 will be described later in detail.

[0186] If the fracturing position of the liquid film of the hollow-conic-shape jetting water 510 is periodically varied, then after the liquid film of the hollow-conic-shape jetting water 510 is fractured, the particle diameter and flow velocity of the granular water flows 520 are periodically varied. This can provide an adequate feeling of volume required for bottom washing, and gently wash the human private parts.

[0187] Furthermore, if the fracturing position of the liquid film of the hollow-conic-shape jetting water 510 is periodically varied, the length of the liquid film and the thickness of the liquid film at the time of fracturing of the liquid film of the hollow-conic-shape jetting water 510 are periodically varied. Thus, the first granular water flows 521 (or first water flow group 521 a) and the second granular water flows 522 (or second water flow group 522a) are generated by periodically varying the length of the liquid film and the thickness of the liquid film at the time of fracturing of the liquid film of the hollow-conic-shape jetting water 510.

[0188] The first jetting water 501 and the second jetting water 502 independently impinge on the human private parts. That is, the first water flow group 521 a and the second water flow group 522a independently impinge on the human private parts. In other words, the first jetting water 501 (or first water flow group 521 a) and the second jetting water 502 (or second water flow group 522a) impinge on the human private parts in the state of not interfering with each other, or in the state in which one is not disturbed by the other.

[0189] That is, the liquid film of the first hollow-conic-shape jetting water 511 is fractured at a position nearer to the human private parts, and fractured in a more spread state, than the liquid film of the second hollow-conic-shape jetting water 512. Thus, the first jetting water 501 impinges on the outer peripheral part of the human private parts with the hollow portion less filled with the first granular water flows 521 than the second jetting water 502. Accordingly, as shown in FIG. 19, the first jetting water 501 (or first water flow group 521a) impinges on the outer peripheral part of the human private parts as ring-shaped jetting water.

[0190] On the other hand, the liquid film of the second hollow-conic-shape jetting water 512 is fractured at a position farther from the human private parts, and fractured in a less spread state, than the liquid film of the first hollow-conic-shape jetting water 511. Accordingly, the second granular water flows 522 are attracted to the hollow portion for a longer time than the first granular water flows 521. Thus, the second jetting water 502 impinges on the central part of the human private parts with the hollow portion more filled with the second granular water flows 522 than the first jetting water 501. Accordingly, as shown in FIG. 19, the second jetting water 502 (or second water flow group 522a) impinges on the central part of the human private parts as solid jetting water.

[0191] As shown in FIG. 19, the second jetting water 502 (or second water flow group 522a) impinges on the human private parts as solid jetting water inside the first jetting water 501 (or first water flow group 521a) impinging on the human private parts as ring-shaped jetting water.

[0192] Thus, the first jetting water 501 for providing the feeling of volume impinges as ring-shaped jetting water on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, the first jetting water 501 can provide a sufficient feeling of volume or a firm feeling of volume. On the other hand, the second jetting water 502 impinges as solid jetting water on the central part of the human private parts with a smaller particle diameter and a slower flow velocity. Thus, while ensuring washing power, the second jetting water 502 can quickly wash away dirt in the central part of the human private parts, and gently wash the central part of the human private parts.

[0193] Furthermore, as described above, as a result, the first jetting water 501 and the second jetting water 502 are alternately jetted from the nozzle 410. More specifically, the first jetting water including ring-shaped jetting water and the second jetting water including solid jetting water are alternately jetted. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Thus, at a small flow rate, the feeling of volume can be provided, and the washing power can be ensured. Furthermore, as described above, the first jetting water 501 and the second jetting water 502 independently impinge on the human private parts. This can suppress the feeling of emptiness of the hollow portion at a small flow rate, and wash a wide range gently and quickly at once. Thus, comfortable bottom washing can be realized.

[0194] The time interval at which the first water flow group 521a and the second water flow group 522a impinge on the human private parts is a time interval at which the user feels the water as continuous jetting water. Here, a human feels the water as continuous jetting water in the case where the time between the timing of impingement of the first jetting water 501 and the timing of impingement of the subsequent first jetting water 501 is e.g. approximately 0.01-0.07 seconds. That is, the range of the frequency (perception limit frequency) at which the user feels the water as continuous jetting water is e.g. approximately 15-100 hertz (Hz).

[0195] Thus, by the first water flow group 521 a having a larger particle diameter and a faster flow velocity, a sufficient impinging water force required for bottom washing can be provided. On the other hand, by the second water flow group 522a having a smaller particle diameter and a slower flow velocity, a wide range can be washed gently and quickly at once without discomfort experienced at the time of washing with e.g. an unnecessarily large flow rate. Furthermore, the water is caused to impinge with a time interval at which a human feels the water as continuous jetting water. Thus, at a smaller flow rate, an adequate feeling of volume required for bottom washing can be provided to a wider range. Furthermore, a sanitary washing apparatus capable of realizing comfortable bottom washing can be provided.

[0196] In other words, this embodiment can provide compatibility between an adequate feeling of volume required for bottom washing and high quality washing comfort. The high quality washing comfort can be realized by e.g. gentle washing, washing in an enveloping manner, and washing suppressing water splash. This can provide a sanitary washing apparatus enabling a user to enjoy washing the human private parts.

[0197] At the time of transition from the first jetting water 501 to the second jetting water 502, or at the time of transition from the second jetting water 502 to the first jetting water 501 , the ring-shaped jetting water and the solid jetting water may slightly interfere with each other. For instance, the ring-shaped jetting water may flow to the inside of the ring and interfere with the solid jetting water. Alternatively, the solid jetting water may flow to the outside of the ring and interfere with the ring-shaped jetting water. Also in this case, in this specification, jetting waters independently impinging on the human private parts, or jetting waters impinging on the human private parts in the state of not interfering with each other, or in the state in which one is not disturbed by the other, are referred to as first jetting water 501 and second jetting water 502. Then, inside the first jetting water 501 (or first water flow group 521 a) impinging on the human private parts as ring-shaped jetting water, the second jetting water 502 (or second water flow group 522a) impinges on the human private parts as solid jetting water independently of the first jetting water 501 (or first water flow group 521a).

[0198] FIG. 20 is a graph showing the impinging water force of the water at a position separated by a prescribed distance from the impingement part or the jetting hole.

[0199] As described above with reference to FIGS. 17 to 19, the first granular water flows 521 impinge on the outer peripheral part of the human private parts with a larger particle diameter and a faster flow velocity than the second granular water flows 522. Thus, as shown in FIG. 20, the impinging water force of the first jetting water 501 at the human private parts is larger than the impinging water force of the second jetting water 502 at the human private parts. That is, by increasing the flow velocity of the water 500 jetted from the nozzle 410, the sanitary washing apparatus 100 according to this embodiment can make the impinging water force of the first jetting water 501 at the human private parts larger than the impinging water force of the second jetting water 502 at the human private parts. Furthermore, the impinging water force of the first jetting water 501 at the human private parts is larger than the impinging water force F1 causing the user to feel the feeling of volume.

[0200] Accordingly, the impinging water force can be increased by increasing the flow velocity of the water 500 even without increasing the amount of water 500 squirted from the nozzle 410. Thus, at a small flow rate, a sufficient feeling of volume can be provided, and a sufficient washing power can be ensured. Furthermore, the first jetting water 501 impinges on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, a sufficient feeling of volume required for bottom washing can be provided.

[0201] Furthermore, as shown in FIG. 20, the impinging water force of the first jetting water 501 at the central part of the human private parts is smaller than the impinging water force of the second jetting water 502 at the human private parts, and smaller than the impinging water force F2 needed to remove dirt. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. For instance, also for users having hemorrhoids, lacerations, or abrasions due to excessive wipe-up in the human private parts, comfortable bottom washing can be realized.

[0202]  As described above with reference to FIGS. 17 to 19, the second granular water flows 522 impinge on the central part of the human private parts with a smaller particle diameter and a slower flow velocity than the first granular water flows 521. Thus, as shown in FIG. 20, the impinging water force of the second jetting water 502 at the human private parts is smaller than the impinging water force of the first jetting water 501 at the human private parts. Furthermore, the impinging water force of the second jetting water 502 at the human private parts is smaller than the impinging water force F1 causing the user to feel the feeling of volume, and larger than the impinging water force F2 needed to remove dirt. The range of impingement of the second jetting water 502 can include the range where dirt is typically attached. Thus, while ensuring a sufficient washing power, the second jetting water 502 can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts, and wash a wide range gently and quickly at once.

[0203] Next, an example of the nozzle 410 of this embodiment is described with reference to the drawings.

[0204] FIG. 21 is a sectional schematic view illustrating the example of the nozzle of this embodiment.

[0205] As shown in FIG. 21, the nozzle 410 of this example includes a nozzle body (jetting means) 420 and a throat (liquid film thickness expanding means and fracturing means) 430. The nozzle body 420 includes therein a nozzle body flow channel 421 for passing water supplied from a water source, not shown, a swirling chamber 423 capable of generating a swirling flow, and a communication channel 425 for guiding water from the swirling chamber 423 to the throat 430. At the center of the swirling chamber 423, a protrusion 424 for generating a swirling flow with stabler swirling power is provided.

[0206] The swirling chamber 423 is a hollow chamber formed from a large diameter inner peripheral wall 423e having a larger diameter at the bottom, and an inclined inner peripheral wall 423f having a diameter shrinking toward the communication channel 425. At one end of the inclined inner peripheral wall 423f, the inclined inner peripheral wall 423f is connected to the communication channel 425. On the other hand, the nozzle body flow channel 421 is connected eccentrically to the swirling chamber 423. More specifically, the nozzle body flow channel 421 is connected in the tangential direction of the large diameter inner peripheral wall 423e of the swirling chamber 423.

[0207] The throat 430 is formed in a tubular shape. The throat 430 includes therein a throat flow channel 431 for passing water jetted from the communication channel 425 of the nozzle body 420. Furthermore, a jetting hole 433 is formed at one end of the throat flow channel 431. The jetting hole 433 is configured so that the water passed through the throat flow channel 431 is jetted outside the throat 430. The jetting hole 433 shown in FIG. 21 corresponds to the jetting hole 411 shown in FIGS. 1 and 17. The throat flow channel 431 near the jetting hole 433 includes a taper part 432 having a flow channel expanding toward the jetting hole 433.

[0208] In the nozzle 410 of this example, a gap is provided between the nozzle body 420 and the throat 430. However, this gap does not necessarily need to be provided. That is, the nozzle body 420 and the throat 430 may be integrally formed so that the communication channel 425 and the throat flow channel 431 are connected.

[0209] When water is supplied to the nozzle 410 from a water source, not shown, the water passes through the nozzle body flow channel 421 and flows into the swirling chamber 423. Here, the nozzle body flow channel 421 is connected in the tangential direction of the large diameter inner peripheral wall 423e of the swirling chamber 423. Thus, the water poured into the swirling chamber 423 swirls along the large diameter inner peripheral wall 423e and the inclined inner peripheral wall 423f. Then, the water swirled in the swirling chamber 423 passes through the communication channel 425 while maintaining the swirling power, and is jetted from one end (jetting port) of the communication channel 425 into the throat flow channel 431 of the throat 430. At this time, the water jetted from the nozzle body 420 maintains the swirling power. Thus, the water is jetted in a hollow conic shape as a liquid film including a hollow portion in the central part.

[0210] The water jetted in the hollow conic shape from the nozzle body 420 is received by the inner wall of the throat flow channel 431. Then, the water poured into the throat flow channel 431 flows along the inner wall of the throat flow channel 431 while maintaining the swirling power, and is guided to the jetting hole 433. That is, the water passing through the throat flow channel 431 flows in contact with the inner wall of the throat flow channel 431. Thus, the water flowing in the throat flow channel 431 is subjected to resistance due to the frictional force from the inner wall of the throat flow channel 431. The flow velocity of the water is slowed down toward the jetting hole 433. Thus, as shown in FIG. 21 , the thickness of the liquid film near the jetting hole 433 is thicker than the thickness of the liquid film jetted from the nozzle body 420, or the thickness of the liquid film just poured into the throat flow channel 431. I n other words, the thickness D2 of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 is thicker than the thickness D1 of the liquid film of the hollow-conic-shape jetting water jetted from the nozzle body 420. That is, in this example, the nozzle body 420 functions as the jetting means 401 described above with reference to FIG. 17.

[0211] Furthermore, the flow velocity of the water flowing in the throat flow channel 431 is faster in the central part of the throat flow channel 431 than near the inner wall, i.e., in the boundary layer, of the throat flow channel 431. That is, the throat 430 can produce a difference between the flow velocity of the water flowing near the inner wall of the throat flow channel 431 and the flow velocity of the water flowing on the central part side of the neighborhood of the inner wall of the throat flow channel 431. I n other words, the throat 430 can produce a velocity difference between the flow outside (on the inner wall side of the throat flow channel 431) the liquid film of the water and the flow inside (on the central part side of the throat flow channel 431) the liquid film of the water. This is because the water outside (on the inner wall side of the throat flow channel 431) the liquid film is subjected to a larger frictional force from the inner wall of the throat flow channel 431 than the water inside (on the central part side of the throat flow channel 431) the liquid film. Thus, the outside water is further decelerated than the inside water.

[0212] Thus, inside the water flowing in the throat flow channel 431, as indicated by arrow A1 shown in FIG. 21, vortices are generated in a direction traversing the liquid film. Furthermore, in the throat flow channel 431 near the jetting hole 433, a taper part 432 having a flow channel expanding toward the jetting hole 433 is formed. Thus, the water jetted from the jetting hole 433 flows along the taper part 432. Accordingly, inside the water jetted from the jetting hole 433, vortices are more likely to occur in a direction traversing the liquid film.

[0213] Then, the water jetted from the jetting hole 433 is jetted as a liquid film including a hollow portion in the central part, i.e., as hollow-conic-shape jetting water 510, and transitions to granular water flows 520 at a position spaced to some extent from the jetting hole 433. More specifically, inside the hollow-conic-shape jetting water 510 jetted from the jetting hole 433, vortices are generated in a direction traversing the liquid film. Thus, at a position spaced to some extent from the jetting hole 433, a crack occurs between adjacent vortices. Accordingly, as shown in FIG. 21, the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 is fractured at a position spaced to some extent from the jetting hole 433. Thus, the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 transitions to granular water flows 520. That is, the throat 430 of this example also functions as a fracturing means in addition to functioning as a liquid film thickness expanding means 402.

[0214] Here, the fracturing means is not limited to the throat 430. For instance, the fracturing means may include a fluid squirting device, not shown, capable of generating a liquid flow, an air flow and the like. The fluid squirting device, not shown, squirts a liquid flow or air flow from a squirting hole, not shown, so that the liquid flow or air flow can collide with the hollow-conic-shape jetting water 510 jetted from the jetting hole 433. Thus, the hollow-conic-shape jetting water 510 jetted from the jetting hole 433 may be fractured by the liquid flow or air flow squirted from the squirting hole and transition to granular water flows 520.

[0215] Next, the pulsation generating means is described with reference to the drawings.

[0216] FIG. 22 is a sectional schematic view illustrating the internal structure of the pulsation generating means of this embodiment.

[0217] The sanitary washing apparatus 100 according to this embodiment includes a pulsation generating means (fracturing position varying means) 470. The pulsation generating means 470 can alternately jet the first jetting water 501 and the second jetting water 502. Furthermore, the pulsation generating means 470 can periodically vary the fracturing position of the liquid film of the hollow-conic-shape jetting water 510.

[0218] Specifically, the pulsation generating means 470 can apply pulsation to the flow of water in the nozzle body flow channel 421, and can apply pulsation to the water jetted from the jetting hole 433. Here, the term "pulsation" used herein refers to pressure variation caused by the pulsation generating means 470. Thus, the pulsation generating means 470 is a device for varying the pressure of water in the nozzle body flow channel 421.

[0219] As shown in FIG. 22, the pulsation generating means 470 includes a cylinder 471 connected to the nozzle body flow channel 421, a plunger 472 reciprocably provided inside the cylinder 471, a check valve 473 provided inside the plunger 472, and a pulsation generating coil 474 for reciprocating the plunger 472 under a controlled excitation voltage.

[0220] The check valve is disposed so that the pressure of water on the downstream side of the pulsation generating means 470 increases when the position of the plunger 472 is changed to the nozzle 410 side (downstream side), and that the pressure of water on the downstream side of the pulsation generating means 470 decreases when the position of the plunger 472 is changed to the side opposite to the nozzle 410 (upstream side). In other words, the pressure of water on the upstream side of the pulsation generating means 470 decreases when the position of the plunger 472 is changed to the nozzle 410 side (downstream side). The pressure of water on the upstream side of the pulsation generating means 470 increases when the position of the plunger 472 is changed to the side opposite to the nozzle 410 (upstream side).

[0221] The plunger 472 is moved to the upstream or downstream side by controlling the excitation of the pulsation generating coil 474. That is, to add pulsation to the water in the nozzle body flow channel 421 (to vary the pressure of the water in the nozzle body flow channel 421), the plunger 472 is reciprocated in the axial direction (upstream/downstream direction) of the cylinder 471 by controlling the excitation voltage supplied to the pulsation generating coil 474.

[0222] Here, by excitation of the pulsation generating coil 474, the plunger 472 moves from the original position (plunger original position) as shown to the downstream side 475. Then, when the excitation of the pulsation generating coil 474 is extinguished, the plunger 472 returns to the original position by the biasing force of a return spring 476. At this time, a buffer spring 477 buffers the return motion of the plunger 472. The plunger 472 includes therein a duckbill check valve 473 to prevent backflow to the upstream side.

[0223] Thus, when the plunger 472 moves from the plunger original position to the downstream side, the plunger 472 can pressurize water in the cylinder 471 to drive the water to the nozzle body flow channel 421 on the downstream side. In other words, when the plunger 472 moves from the plunger original position to the downstream side, the plunger 472 can depressurize water in the nozzle body flow channel 421 on the upstream side to suck the water into the cylinder 471. Here, because the plunger original position and the position after the motion to the downstream side are always the same, the amount of water fed to the nozzle body flow channel 421 on the downstream side in response to the motion of the plunger 472 is constant.

[0224] Subsequently, at the time of return to the original position, water flows into the cylinder 471 through the check valve 473. Thus, at the next time when the plunger 472 moves to the downstream side, a constant amount of water is newly fed to the nozzle body flow channel 421 on the downstream side. Thus, the pulsation generating means 470 shown in FIG. 22 can apply pulsation to the flow of water in the nozzle body flow channel 421.

[0225] Here, the pulsation generating means of this embodiment is not limited thereto.

[0226] For instance, the pulsation generating means of this embodiment may have a dual configuration composed of a first water pressure modulator and a second water pressure modulator. The first water pressure modulator and the second water pressure modulator include cylinders each including a cylindrical space. A piston is provided in the cylinder. The piston is equipped with e.g. an O-ring. Each space defined by the piston and the cylinder constitutes a pressurizing chamber.

[0227] The pistons can be vertically reciprocated. When the pressurizing chamber is filled with water, if the piston moves from the lower dead center (original position) to the upper dead center, the volume of the pressurizing chamber decreases. Thus, the water is pressurized and driven toward the downstream side of the nozzle body flow channel 421.

[0228] Then, in return from the upper dead center to the lower dead center (original position), the pressure in the pressurizing chamber decreases, and the water flows into the pressurizing chamber. Subsequently, at the next time of piston movement, the water is pressurized again. This process is successively performed to generate pressure variation, i.e., pulsation. Thus, pulsation may be applied to the flow of water in the nozzle body flow channel 421.

[0229] Next, the relationship between the operation of the pulsation generating means and the flow velocity of water is described with reference to the drawings.

[0230] FIGS. 23A and 23B are graphs illustrating a voltage waveform applied to the pulsation generating means and a flow velocity waveform of water on the downstream side of the pulsation generating means.

[0231] Here, FIG. 23A is a graph illustrating a voltage waveform applied to the pulsation generating means of this embodiment. FIG. 23B is a graph illustrating a flow velocity waveform of water on the downstream side of the pulsation generating means of this embodiment.

[0232] As described above with reference to FIG. 22, by controlling the excitation voltage supplied to the pulsation generating coil 474, the plunger 472 can be driven to apply pulsation to water in the nozzle body flow channel 421. The frequency (1/T1) of the waveform of the voltage supplied to the pulsation generating coil 474 is 50 Hz or more and 100 Hz or less. Specifically, the frequency is e.g. approximately 70 Hz. The maximum of the time t1 for supplying voltage is e.g. approximately 3.25 milliseconds (ms). Thus, the maximum of the duty cycle of the waveform of the voltage supplied to the pulsation generating coil 474 is e.g. approximately 23.2%.

[0233] First, when supply of voltage to the pulsation generating coil 474 is stopped, the plunger 472 moves to the upstream side, and the pressure of water on the downstream side of the pulsation generating means 470 decreases. Thus, like flow velocity V1-V2 shown in FIG. 23B, the flow velocity of water on the downstream side of the pulsation generating means 470 decreases. Then, the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 411 decreases. Thus, the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 becomes faster with the distance from the jetting hole 411. That is, a flow velocity difference occurs between the liquid film of the hollow-conic-shape jetting water 510 located at a position relatively far from the jetting hole 411 and the liquid film of the hollow-conic-shape jetting water 510 located at a position relatively near to the jetting hole 411. Due to this flow velocity difference, the liquid film of the hollow-conic-shape jetting water 510 is placed in a thinly stretched state.

[0234] Thus, in the initial stage of the change of the flow velocity of water from the flow velocity V1 to the flow velocity V2, the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position farther from the jetting hole 411 than in the case where there is no pressure variation by the pulsation generating means 470. The hollow-conic-shape jetting water 510 having a thin thickness of the liquid film transitions to granular water flows 520 in the state of fast flow velocity at the position far from the jetting hole 411. Thus, granular water flows 520 having a smaller particle diameter and a faster flow velocity are generated.

[0235] Next, in the last stage of the change of the flow velocity of water from the flow velocity V1 to the flow velocity V2, the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position nearer to the jetting hole 411 than in the case where there is no pressure variation by the pulsation generating means 470. The hollow-conic-shape jetting water 510 having a thin thickness of the liquid film transitions to granular water flows 520 in the state of slow flow velocity at the position near to the jetting hole 411. Thus, granular water flows 520 having a smaller particle diameter and a slower flow velocity are generated. The granular water flows at this time corresponds to the second granular water flows 522 described above with reference to FIGS. 17 to 19. That is, the water jetted in the last stage of the change of the flow velocity of water from the flow velocity V1 to the flow velocity V2 corresponds to the second jetting water 502.

[0236] On the other hand, when supply of voltage to the pulsation generating coil 474 is started, the plunger 472 moves to the downstream side, and the pressure of water on the downstream side of the pulsation generating means 470 increases. Thus, like flow velocity V3-V4 shown in FIG. 23B, the flow velocity of water on the downstream side of the pulsation generating means 470 increases. Then, the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 jetted from the jetting hole 411 increases. Thus, the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 becomes slower with the distance from the jetting hole 411. That is, a flow velocity difference occurs between the liquid film of the hollow-conic-shape jetting water 510 located at a position relatively far from the jetting hole 411 and the liquid film of the hollow-conic-shape jetting water 510 located at a position relatively near to the jetting hole 411. Due to this flow velocity difference, the thickness of the liquid film of the hollow-conic-shape jetting water 510 becomes thicker with the distance from the jetting hole 411.

[0237] Thus, in the initial stage of the change of the flow velocity of water from the flow velocity V3 to the flow velocity V4, promotion of fracturing by the flow velocity difference inside the liquid film is added, and the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position nearer to the jetting hole 411 than in the case where there is no pressure variation by the pulsation generating means 470. The hollow-conic-shape jetting water 510 having a thick thickness of the liquid film transitions to granular water flows 520 in the state of slow flow velocity at the position near to the jetting hole 411. Thus, granular water flows 520 having a smaller particle diameter and a slower flow velocity are generated.

[0238] Next, in the last stage of the change of the flow velocity of water from the flow velocity V3 to the flow velocity V4, the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position farther from the jetting hole 411 than in the case where there is no pressure variation by the pulsation generating means 470. The hollow-conic-shape jetting water 510 having a thick thickness of the liquid film transitions to granular water flows 520 in the state of fast flow velocity at the position far from the jetting hole 411. Thus, granular water flows 520 having a larger particle diameter and a faster flow velocity are generated. The granular water flows at this time corresponds to the first granular water flows 521 described above with reference to FIGS. 17 to 19. That is, the water jetted in the last stage of the change of the flow velocity of water from the flow velocity V3 to the flow velocity V4 corresponds to the first jetting water 501.

[0239] Thus, the pulsation generating means 470 can change the flow velocity of the water 500 jetted from the jetting hole 411. Furthermore, the pulsation generating means 470 can alternately jet the first jetting water 501 including ring-shaped jetting water and the second jetting water 502 including solid jetting water. Furthermore, the pulsation generating means 470 can periodically vary the fracturing position of the liquid film of the hollow-conic-shape jetting water 510.

[0240] FIG. 24 is a graph illustrating the velocity distribution of particles passing near the impingement position.

[0241] The inventor measured the velocity distribution of particles (liquid drops or granular water flows) passing near the impingement position in the case where the pulsation generating means 470 applied pulsation to the flow of water in the nozzle body flow channel 421. Furthermore, the inventor measured the velocity distribution of particles passing near the impingement position in the case where the pulsation generating means 470 applied no pulsation to the flow of water in the nozzle body flow channel 421. The amount of water supplied to the pulsation generating means 470 was set constant at approximately 430 cc/min irrespective of the presence or absence of pulsation. An example of the result is as shown in FIG. 24.

[0242] As shown in FIG. 24, the velocity distribution in the case where the pulsation generating means 470 applies pulsation to the flow of water in the nozzle body flow channel 421 is broader than the velocity distribution in the case where the pulsation generating means 470 applies no pulsation to the flow of water in the nozzle body flow channel 421. I n other words, the velocity distribution in the case where the pulsation generating means 470 applies no pulsation to the flow of water in the nozzle body flow channel 421 is more concentrated at a prescribed flow velocity than the velocity distribution in the case where the pulsation generating means 470 applies pulsation to the flow of water in the nozzle body flow channel 421. This indicates that if the pulsation generating means 470 applies pulsation to the flow of water in the nozzle body flow channel 421 , granular water flows 520 having a faster flow velocity or granular water flows 520 having a slower flow velocity can be generated as compared with the case where the pulsation generating means 470 applies no pulsation to the flow of water in the nozzle body flow channel 421.

[0243] Here, the velocity distribution in the case where the pulsation generating means 470 applies pulsation to the flow of water in the nozzle body flow channel 421 is decomposed into a velocity distribution for high spatial occupancy ratio of liquid drops and a velocity distribution for low spatial occupancy ratio of liquid drops. Then, as shown in FIG. 24, the peak of the velocity distribution for high spatial occupancy ratio of liquid drops is located on the fast flow velocity side of the peak of the velocity distribution for low spatial occupancy ratio of liquid drops. Here, the term "spatial occupancy ratio" used herein refers to the ratio or proportion of volume occupied by liquid drops per unit volume. That is, by changing the velocity distribution of liquid drops by the pulsation generating means 470, the spatial occupancy ratio of liquid drops can be changed. This is further described below.

[0244] FIG. 25 is a graph illustrating the spatial occupancy ratio of particles passing near the impingement position.

[0245] As described above with reference to FIGS. 23A and 23B, the pulsation generating means 470 can change the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520. As described above with reference to FIG. 24, by changing the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, the pulsation generating means 470 can change the spatial occupancy ratio of particles passing near the impingement position. Thus, the pulsation generating means 470 can change the amount of water at the impingement position.

[0246] The inventor measured the temporal progress of the spatial occupancy ratio of particles passing near the impingement position. An example of the result is as shown in FIG. 25. When the water force of the water 500 squirted from the nozzle 410 is "Water force 4" and "Water force 5", the pulsation generating means 470 applies pulsation to the flow of water in the nozzle body flow channel 421. The frequency of the waveform of the voltage supplied to the pulsation generating coil 474 is 50 Hz or more and 100 Hz or less for "Water force 4" and "Water force 5". Specifically, the frequency is approximately 70 Hz. The duty cycle of the waveform of the voltage supplied to the pulsation generating coil 474 is approximately 13.3% for "Water force 4", and approximately 23.2% for "Water force 5".

[0247] On the other hand, when the water force of the water 500 squirted from the nozzle 410 is "Water force 3", the pulsation generating means 470 applies no pulsation to the flow of water in the nozzle body flow channel 421. The amount of water supplied to the pulsation generating means 470 was set constant at approximately 430 cc/min irrespective of the presence or absence of pulsation. That is, "Water force 4" and "Water force 5" are mutually different in the duty cycle of the waveform of the voltage supplied to the pulsation generating coil 474, but identical in the frequency of the waveform of the voltage supplied to the pulsation generating coil 474 and the amount of water supplied to the pulsation generating means 470.

[0248] As shown in FIG. 25, by applying pulsation to the flow of water in the nozzle body flow channel 421, the pulsation generating means 470 can alternately generate a high state and a low state of the spatial occupancy ratio of particles passing near the impingement position. The high state of the spatial occupancy ratio of particles passing near the impingement position is as represented by e.g. the inset photograph P1 shown in FIG. 25. In the inset photograph P1 shown in FIG. 25, particles flow from the left side toward the right side of the inset photograph P1. On the other hand, the low state of the spatial occupancy ratio of particles passing near the impingement position is as represented by e.g. the inset photograph P2 shown in FIG. 25. I n the inset photograph P2 shown in FIG. 25, particles flow from the left side toward the right side of the inset photograph P2.

[0249] As described above with reference to FIG. 24, the peak of the velocity distribution for high spatial occupancy ratio of liquid drops is located on the fast flow velocity side of the peak of the velocity distribution for low spatial occupancy ratio of liquid drops. Thus, by making faster the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, the pulsation generating means 470 can realize the high state of the spatial occupancy ratio of particles passing near the impingement position. On the other hand, by making slower the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, the pulsation generating means 470 can realize the low state of the spatial occupancy ratio of particles passing near the impingement position.

[0250] As described above with reference to FIGS. 23A and 23B, the water jetted in the last stage of the increase of the flow velocity of water corresponds to the first jetting water 501. Thus, the inset photograph P1 shown in FIG. 25 represents e.g. the first jetting water 501. On the other hand, the water jetted in the last stage of the decrease of the flow velocity of water corresponds to the second jetting water 502. Thus, the inset photograph P2 shown in FIG. 25 represents e.g. the second jetting water 502.

[0251] Thus, the amount of water of the first jetting water 501 (or first water flow group 521a) at the impingement position (e.g., human private parts) is larger than the amount of water of the second jetting water 502 (or second water flow group 522a) at the impingement position (e.g., human private parts). Accordingly, the first jetting water 501 can provide a sufficient feeling of volume required for bottom washing.

[0252] Here, as shown in FIG. 25, the pulsation generating means 470 can produce a difference between the spatial occupancy ratio of particles for "Water force 4" and the spatial occupancy ratio of particles for "Water force 5". That is, the spatial occupancy ratio of particles can be changed by changing the duty cycle of the waveform of the voltage supplied to the pulsation generating coil 474 without changing the frequency of the waveform of the voltage supplied to the pulsation generating coil 474 and the amount of water supplied to the pulsation generating means 470. In other words, by changing the duty cycle of the waveform of the voltage supplied to the pulsation generating coil 474, the amount of water at the impingement position or the impinging water force can be changed as represented by e.g. the inset photograph P1 and the inset photograph P2 shown in FIG. 25.

[0253] FIGS. 26A to 27D are photographs showing the state of the water jetted from the nozzle of this embodiment.

[0254] The inventor photographed the state of the water jetted from the nozzle 410 at every 1/8 period of the waveform of the voltage applied to the pulsation generating means 470. FIGS. 26A to 26E and FIGS. 27A to 27D show the photographs in the order of time.

[0255] In the state shown in FIG. 26A, the liquid film of the hollow-conic-shape jetting water 510 is relatively thin. Thus, the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position relatively near to the jetting hole 411 and transitions to liquid drops having a relatively small diameter. As indicated by the arrow shown in FIG. 26A, the length of the liquid film of the hollow-conic-shape jetting water 510 is relatively short. That is, in the state shown in FIG. 26A, the second jetting water 502 is generated. I n the solid enclosing line shown in FIG. 26A, the liquid film of the second hollow-conic-shape jetting water 512 is fractured and transitions to second granular water flows 522.

[0256] Next, as shown in FIGS. 26B to 26D, the second granular water flows 522 (or second water flow group 522a) generated in FIG. 26A travel toward the impingement position. Furthermore, the length of the liquid film of the hollow-conic-shape jetting water 510 is gradually elongated. The impingement position is a position separated by e.g. approximately 40-60 millimeters (mm) from the jetting hole 411. Here, the impingement position shown in FIGS. 26A to 27D is a position separated by approximately 40 mm from the jetting hole 411.

[0257] Next, in the state shown in FIG. 26E, the liquid film of the hollow-conic-shape jetting water 510 is relatively thick. Thus, the liquid film of the hollow-conic-shape jetting water 510 is fractured at a position relatively far from the jetting hole 411 and transitions to liquid drops having a relatively large diameter. As indicated by the arrow shown in FIG. 26E, the length of the liquid film of the hollow-conic-shape jetting water 510 is relatively long. That is, in the state shown in FIG. 26E, the first jetting water 501 is generated. In the dashed enclosing line shown in FIG. 26E, the liquid film of the first hollow-conic-shape jetting water 511 is fractured and transitions to first granular water flows 521.

[0258] At this time, the second granular water flows 522 in the solid enclosing line are about to reach the impingement position. Thus, although the flow velocity of the first granular water flows 521 is faster than the flow velocity of the second granular water flows 522, as shown in FIG. 27A, the first granular water flows 521 in the dashed enclosing line reach the impingement position after the second granular water flows 522 in the solid enclosing line passes through the impingement position.

[0259] Next, as shown in FIG. 27B, after passing through the impingement position, the first granular water flows 521 in the dashed enclosing line catch up with the second granular water flows 522 in the solid enclosing line. That is, the first granular water flows 521 (or first water flow group 521 a) do not overtake the second granular water flows 522 (or second water flow group 522a) before the first granular water flows 521 (or first water flow group 521a) reach the impingement position.

[0260] Next, as shown in FIGS. 27C and 27D, the first granular water flows 521 and the second granular water flows 522 further proceed. Then, the state of the water 500 jetted from the nozzle 410 returns to the state shown in FIG. 26A.

[0261] Thus, in this embodiment, the first granular water flows 521 (or first water flow group 521 a) do not overtake the second granular water flows 522 (or second water flow group 522a) before the first granular water flows 521 (or first water flow group 521a) reach the impingement position. That is, the first granular water flows 521 (or first water flow group 521a) and the second granular water flows 522 (or second water flow group 522a) alternately impinge on the human private parts. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Furthermore, at a small flow rate, the feeling of volume can be provided, and a wide range can be washed gently and quickly at once.

[0262] Next, a further alternative embodiment of this invention is described.

[0263] FIG. 28 is a conceptual schematic view showing a main part configuration of a sanitary washing apparatus according to the further alternative embodiment of this invention.

[0264] As described above with reference to FIG. 17, the liquid film of the first hollow-conic-shape jetting water 511 is fractured in a longer state, i.e., at a position farther from the jetting hole 411, than the liquid film of the second hollow-conic-shape jetting water 512. Thus, the liquid film of the first hollow-conic-shape jetting water 511 is fractured in a more spread state than the liquid film of the second hollow-conic-shape jetting water 512. Accordingly, as described above with reference to FIG. 18A, the first granular water flows 521 impinge on the outer peripheral part of the human private parts with a larger particle diameter and a faster flow velocity than the second granular water flows 522. Furthermore, most of the first granular water flows 521 impinge before filling the hollow portion.

[0265] In other words, the liquid film of the first hollow-conic-shape jetting water 511 is fractured at a position nearer to the human private parts, and fractured in a more spread state, than the liquid film of the second hollow-conic-shape jetting water 512. Thus, the first jetting water 501 impinges on the outer peripheral part of the human private parts with the hollow portion less filled with the first granular water flows 521 than the second jetting water 502. Accordingly, as described above with reference to FIG. 19, the first jetting water 501 (or first water flow group 521a) impinges on the outer peripheral part of the human private parts as ring-shaped jetting water.

[0266] Thus, as indicated by arrow A11 and arrow A12 shown in FIG. 18A, the first jetting water 501 impinges on the outer peripheral part of the human private parts as the first granular water flows 521, and includes a flow toward the central part of the human private parts.

[0267] On the other hand, the second jetting water 502 has an action opposite to the first jetting water 501. That is, the liquid film of the second hollow-conic-shape jetting water 512 is fractured into second granular water flows 522 in a thinner and shorter state than the liquid film of the first hollow-conic-shape jetting water 511. Thus, the second granular water flows 522 have a smaller particle diameter and a slower flow velocity than the first granular water flows 521.

[0268] Furthermore, the liquid film of the second hollow-conic-shape jetting water 512 is fractured in a less spread state than the liquid film of the first hollow-conic-shape jetting water 511. Accordingly, as described above with reference to FIG. 18B, the second granular water flows 522 impinge on the central part of the human private parts with a smaller particle diameter and a slower flow velocity than the first granular water flows 521. Furthermore, the second granular water flows 522 impinge while filling the hollow portion.

[0269] In other words, the liquid film of the second hollow-conic-shape jetting water 512 is fractured at a position farther from the human private parts, and fractured in a less spread state, than the liquid film of the first hollow-conic-shape jetting water 511. Accordingly, the second granular water flows 522 flow into the hollow portion for a longer time than the first granular water flows 521. Thus, the second jetting water 502 impinges on the central part of the human private parts with the hollow portion more filled with the second granular water flows 522 than the first jetting water 501. Accordingly, as described above with reference to FIG. 19, the second jetting water 502 (or second water flow group 522a) impinges on the central part of the human private parts as solid jetting water.

[0270] Thus, as indicated by arrow A13 and arrow A14 shown in FIG. 18B, the second jetting water 502 impinges on the central part of the human private parts as the second granular water flows 522, and includes a flow toward the outer peripheral part of the human private parts.

[0271] According to this embodiment, the first granular water flows 521 having a larger particle diameter and a faster flow velocity impinge as ring-shaped jetting water on the outer peripheral part of the human private parts. In the neighborhood of the human private parts, the outer peripheral part of the human private parts is likely to feel the feeling of volume. Thus, the first jetting water 501 can provide a sufficient feeling of volume or a firm feeling of volume. On the other hand, the second jetting water 502 having a smaller particle diameter and a slower flow velocity impinges as solid jetting water on the central part of the human private parts. Thus, while ensuring the washing power, the second jetting water 502 can quickly wash away the dirt in the central part of the human private parts, and gently wash the central part of the human private parts. This can suppress that strong stimuli are unnecessarily applied to the central part of the human private parts compared with the case where e.g. a rectilinear flow impinges on the central part of the human private parts. For instance, also for users having hemorrhoids, lacerations, or abrasions due to excessive wipe-up in the human private parts, comfortable bottom washing can be realized.

[0272] Furthermore, the amount of water of the first jetting water 501 (or first water flow group 521 a) at the human private parts is larger than the amount of water of the second jetting water 502 (or second water flow group 522a) at the human private parts. Accordingly, the first jetting water 501 can provide a sufficient feeling of volume required for bottom washing.

[0273] The sanitary washing apparatus according to this embodiment has the function of enabling the user to adjust the water force of the water 500 jetted from the nozzle 410.

[0274] First, a sanitary washing apparatus according to a comparative example is described. The sanitary washing apparatus according to the comparative example changes the water force by adjusting the amount of water jetted from the nozzle. Thus, in the case where a stronger water force is specified, the amount of water increases. Accordingly, the washing power is made higher, and the impinging water force at the human private parts is made larger. On the other hand, in the case where a weaker water force is specified, the impinging water force at the human private parts is made smaller. Thus, in the case where a weaker water force is specified, although gentle washing for the user, the washing power may be made lower because the amount of water is small.

[0275] In contrast, as shown in FIG. 28, the sanitary washing apparatus according to this embodiment includes a water force adjusting means 406. The water force adjusting means 406 can adjust the impinging water force of the water 500 impinging on the human private parts. Furthermore, in accordance with the water force specified by the user, the water force adjusting means 406 can change the timings at which the first water flow group 521 a and the second water flow group 522a impinge on the human private parts. This is further described with reference to the drawings.

[0276] FIG. 29 is a graph illustrating the spatial occupancy ratio of particles passing near the impingement position.

[0277] As described later in detail, the water force adjusting means 406 of this embodiment can change the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520. Thus, the water force adjusting means 406 can change the timings at which the first water flow group 521 a and the second water flow group 522a impinge on the human private parts.

[0278] For instance, an example is described in the case where "Water force 4" and "Water force 5" are specified (see FIG. 29). Here, in the case where "Water force 3" is specified, the water force adjusting means 406 does not change the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520.

[0279] In the case where "Water force 4" is specified, the water force adjusting means 406 changes the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, and causes the first water flow group 521a and the second water flow group 522a to impinge on the human private parts at mutually different timings.

[0280] On the other hand, in the case where "Water force 5" is specified, the water force adjusting means 406 changes the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, and causes the first water flow group 521 a and the second water flow group 522a to impinge on the human private parts at generally equal timings.

[0281] Here, the range of "generally equal timings" includes timings different within the range of the frequency (perception limit frequency) at which the user feels the water as continuous jetting water. The range of the perception limit frequency is e.g. approximately 15-100 hertz (Hz).

[0282] As shown in FIG. 29, by changing the flow velocity of the liquid film of the hollow-conic-shape jetting water 510 and the flow velocity of the granular water flows 520, the water force adjusting means 406 can alternately generate a high state and a low state of the spatial occupancy ratio of particles (liquid drops or granular water flows) passing near the impingement position in each of the cases where "Water force 4" and "Water force 5" are specified.

[0283] As shown in FIG. 29, the peak value of the spatial occupancy ratio in the case where "Water force 5" is specified is higher than the peak value of the spatial occupancy ratio in the case where "Water force 4" is specified. Here, the term "spatial occupancy ratio" used herein refers to the ratio or proportion of volume occupied by liquid drops per unit volume per unit time.

[0284] Within the range of the perception limit frequency, the first water flow group 521a and the second water flow group 522a having mutually different particle diameters are caused to impinge on the human private parts at generally equal timings. This can cause the user to feel that one thick water flow is impinging. Thus, the impinging water force per unit time at the human private parts in the case where "Water force 5" is specified is larger than the impinging water force per unit time at the human private parts in the case where "Water force 4" is specified.

[0285] Thus, in the case where "Water force 5" is specified, the user can be caused to recognize the water as strong jetting water providing the feeling of volume compared with the case where "Water force 4" is specified.

[0286] On the other hand, in each of the cases where "Water force 4" and "Water force 5" are specified, the amount of water supplied to the water force adjusting means 406 is generally equal. Furthermore, as the result of investigation by the inventor, it has been found that the washing power is generally equal as long as the water has an impinging water force above a certain level needed to remove dirt. Thus, the washing power in the case where "Water force 4" is specified is generally equal to the washing power in the case where "Water force 5" is specified. Accordingly, even without changing the amount of water supplied to the water force adjusting means 406, the water force can be adjusted while ensuring the washing power and maintaining the feeling of volume.

[0287] Furthermore, depending on the difference in the advancement distance of the nozzle 410, the distance from the jetting hole 411 to the human private parts may be changed. In this context, in this embodiment, the water force adjusting means 406 changes the timings at which the first water flow group 521 a and the second water flow group 522a impinge on the human private parts. Thus, even in the case where the distance from the jetting hole 411 to the human private parts is changed, the first water flow group 521 a and the second water flow group 522a can be caused to impinge on the human private parts at generally equal timings. This can cause the user to recognize the water as strong jetting water providing the feeling of volume irrespective of the advancement state of the nozzle 410.

[0288] Next, the water force adjusting means is described with reference to the drawings.

[0289] FIGS. 30A to 30C are timing charts for describing the operation of the pulsation generating means of this embodiment.

[0290] Here, FIG. 30A is a graph illustrating voltage pulses applied to the pulsation generating means of this embodiment. FIG. 30B is a graph illustrating the displacement of the plunger. FIG. 30C is a graph illustrating the flow velocity of water on the downstream side of the pulsation generating means.

[0291] The horizontal axis shown in FIGS. 30A to 30C represents time. However, the time scales are not necessarily aligned with each other.

[0292] The water force adjusting means 406 of this embodiment includes a pulsation generating means 470. The pulsation generating means 470 can apply pulsation to the flow of water in the nozzle body flow channel 421, and can apply pulsation to the water jetted from the jetting hole 433. Here, the term "pulsation" used herein refers to pressure variation caused by the pulsation generating means 470. Thus, the pulsation generating means 470 is a device for varying the pressure of water in the nozzle body flow channel 421.

[0293] As described above with reference to FIG. 22, the pulsation generating means 470 includes a cylinder 471 connected to the nozzle body flow channel 421, a plunger 472 reciprocably provided inside the cylinder 471 , a check valve 473 provided inside the plunger 472, and a pulsation generating coil 474 for reciprocating the plunger 472 under a controlled excitation voltage.

[0294] The check valve is disposed so that the pressure of water on the downstream side of the pulsation generating means 470 increases when the position of the plunger 472 is changed to the nozzle 410 side (downstream side), and that the pressure of water on the downstream side of the pulsation generating means 470 decreases when the position of the plunger 472 is changed to the side opposite to the nozzle 410 (upstream side). In other words, the pressure of water on the upstream side of the pulsation generating means 470 decreases when the position of the plunger 472 is changed to the nozzle 410 side (downstream side). The pressure of water on the upstream side of the pulsation generating means 470 increases when the position of the plunger 472 is changed to the side opposite to the nozzle 410 (upstream side).

[0295] The plunger 472 is moved to the upstream or downstream side by controlling the excitation of the pulsation generating coil 474. That is, to add pulsation to the water in the nozzle body flow channel 421 (to vary the pressure of the water in the nozzle body flow channel 421), the plunger 472 is reciprocated in the axial direction (upstream/downstream direction) of the cylinder 471 by controlling the excitation voltage supplied to the pulsation generating coil 474.

[0296] More specifically, the water force adjusting means 406 includes a controller, not shown, and a voltage supplying means such as a power supply, not shown. The controller, not shown, controls the excitation voltage supplied to the pulsation generating coil 474, and supplies voltage to the pulsation generating coil 474 by controlling the voltage supplying means, not shown. Thus, the water force adjusting means 406 applies voltage to the pulsation generating means 470, i.e., supplies voltage to the pulsation generating coil 474. Accordingly, the plunger 472 can be reciprocated in the axial direction of the cylinder 471.

[0297] For instance, the water force adjusting means 406 applies a voltage pulse shown in FIG. 30A to the pulsation generating means 470. Here, the scope of the term "pulse" used herein includes not only rectangular waves, but also waveforms in which the signal is periodically varied. As shown in FIG. 30B, during the on-state of the application voltage (during ON-time of the voltage pulse), by excitation of the pulsation generating coil 474, the plunger 472 moves from the original position (plunger original position) as shown to the downstream side (Y direction shown in FIG. 22) 475. Then, as shown in FIG. 30C, the water in the cylinder 471 is pressurized and accelerated by the plunger 472 and driven to the nozzle body flow channel 421 on the downstream side. In other words, when the plunger 472 moves from the plunger original position to the downstream side, the plunger 472 can depressurize water in the nozzle body flow channel 421 on the upstream side to suck the water into the cylinder 471. At this time, in the case where the plunger original position and the position after the motion to the downstream side are always the same, i.e., in the case where the on-time of the voltage pulse (width of the voltage pulse) is constant, the amount of water fed to the nozzle body flow channel 421 on the downstream side in response to the motion of the plunger 472 is constant.

[0298] On the other hand, in the case where the on-time of the voltage pulse is not constant, the amount of water fed to the nozzle body flow channel 421 on the downstream side in response to the motion of the plunger 472 is not constant. For instance, for a longer on-time of the voltage pulse, the displacement to the Y direction of the plunger 472 is larger. Thus, for a longer on-time of the voltage pulse, the water in the cylinder 471 is further pressurized and accelerated by the plunger 472. As a result, the amount of water driven to the nozzle body flow channel 421 on the downstream side increases instantaneously. The water 500 jetted from the jetting hole 433 at this time is the first jetting water 501.

[0299] Next, the water force adjusting means 406 stops application of voltage to the pulsation generating means 470. Then, as shown in FIG. 30B, the excitation of the pulsation generating coil 474 is extinguished. By the biasing force of a return spring 476, the plunger 472 moves to the upstream side (-Y direction) and returns to the original position. At this time, a buffer spring 477 buffers the return motion of the plunger 472. The plunger 472 includes therein a duckbill check valve 473 to prevent backflow to the upstream side.

[0300] When the plunger 472 returns to the original position, water flows into the cylinder 471 through the check valve 473. At this time, as shown in FIG. 30C, the water on the downstream side of the pulsation generating means 470 is depressurized and decelerated by the plunger 472. Then, the water 500 continues to be jetted from the jetting hole 533. The water 500 jetted from the jetting hole 533 at this time is the second jetting water 502.

[0301] Next, at the next time when the plunger 472 moves to the downstream side, a constant amount of water is newly fed to the nozzle body flow channel 421 on the downstream side. Thus, the pulsation generating means 470 described above with reference to FIG. 22 can apply pulsation to the flow of water in the nozzle body flow channel 421.

[0302] As described above, when the water on the downstream side of the pulsation generating means 470 is pressurized and accelerated by the plunger 472, the water 500 jetted from the jetting hole 433 at this time is the first jetting water 501. On the other hand, when the water on the downstream side of the pulsation generating means 470 is depressurized and decelerated by the plunger 472, the water 500 jetted from the jetting hole 433 at this time is the second jetting water 502. Thus, the amount of water of the first jetting water 501 (or first water flow group 521a) at the human private parts is larger than the amount of water of the second jetting water 502 (or second water flow group 522a) at the human private parts. Accordingly, the first jetting water 501 can provide a sufficient feeling of volume required for bottom washing.

[0303] Next, an example of the operation of the water force adjusting means 406, i.e., an example of the water force adjusting means 406 changing the timings at which the first water flow group 521a and the second water flow group 522a impinge on the human private parts, is described with reference to the drawings.

[0304]  FIGS. 31A to 31C are timing charts for describing the example of the operation of the water force adjusting means.

[0305] FIG. 32 is a plan schematic view for describing the timings at which the first water flow group and the second water flow group impinge on the impingement position.

[0306] Here, FIG. 31A is a graph illustrating voltage pulses applied to the pulsation generating means of this example. FIG. 31B is a graph illustrating the amount of water passing on the downstream side of the pulsation generating means. FIG. 31C is a graph illustrating the amount of water of the first water flow group and the second water flow group in the third on-time.

[0307] The water force adjusting means 406 of this example includes a pulsation generating means 470. In this example, the water force adjusting means 406 sets the period of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the proportion (duty cycle) of the on-time to the period of the voltage pulse. As shown in FIG. 31A, the first on-time t11 is shorter than the second on-time t12 (t11<t12). The second on-time t12 is shorter than the third on-time t13 (t12<t13).

[0308] As described above with reference to FIGS. 30A to 30C, for a longer on-time of the voltage pulse, the displacement to the Y direction (downstream side) of the plunger 472 is larger. Thus, for a longer on-time of the voltage pulse, the water in the cylinder 471 is further pressurized and accelerated by the plunger 472. As a result, as shown in FIGS. 31A and 31B, for a longer on-time of the voltage pulse, the amount of water pressurized and accelerated and passing on the downstream side of the pulsation generating means 470 increases.

[0309] The generation of the first water flow group 521a (or first jetting water 501) is started simultaneously with the timing at which voltage is applied to the pulsation generating means 470. The generation of the second water flow group 522a (or second jetting water 502) is started simultaneously with the timing at which application of voltage to the pulsation generating means 470 is stopped. Thus, as shown in FIG. 31C, the first water flow group 521a is generated between the timing at which voltage is applied to the pulsation generating means 470 and the timing at which application of voltage to the pulsation generating means 470 is stopped. On the other hand, the second water flow group 522a is generated between the timing at which application of voltage to the pulsation generating means 470 is stopped and the next timing at which voltage is applied to the pulsation generating means 470.

[0310] Thus, for a longer on-time of the voltage pulse, the amount of water accelerated by the plunger 472 increases, and the amount of water of the first water flow group 521 a increases. The period of the voltage pulse is constant. Thus, for a longer on-time of the voltage pulse, the off-time of the voltage pulse is shorter. Accordingly, the amount of water of the water flow group (second water flow group 522a) other than the first water flow group 521 a decreases.

[0311] The amount of water shown in FIG. 31B represents the instantaneous flow rate for a prescribed time. FIG. 31B shows that for a longer on-time of the voltage pulse, the maximum instantaneous flow rate is larger. For a larger maximum instantaneous flow rate, the flow velocity of the water flowing into the swirling chamber 423 is made faster. Thus, the flow velocity V11 of the first water flow group 521 a is made faster. Furthermore, as described above, for a longer on-time of the voltage pulse, the amount of water of the second water flow group 522a decreases. Thus, the flow velocity V12 of the second water flow group 522a is made slower. That is, for a longer on-time of the voltage pulse, the flow velocity V11 of the first water flow group 521 a is made faster, and the flow velocity V12 of the second water flow group 522a is made slower.

[0312] On the other hand, for a shorter on-time of the voltage pulse, the amount of water of the first water flow group 521a decreases, and the amount of water of the water flow group (second water flow group 522a) other than the first water flow group 521a increases. Thus, for a shorter on-time of the voltage pulse, the flow velocity V11 of the first water flow group 521 a is made slower, and the flow velocity V12 of the second water flow group 522a is made faster.

[0313] As shown in FIG. 32, in this example, the first jetting water 501 forming the first water flow group 521a after being fractured and the second jetting water 502 forming the second water flow group 522a after being fractured are alternately jetted from the nozzle 410.

[0314] Thus, depending on the flow velocity V11 of the first water flow group 521 a and the flow velocity V12 of the second water flow group 522a, the first water flow group 521 a can catch up with the second water flow group 522a at the impingement position or on the nozzle 410 side of the impingement position. For instance, in the case where the flow velocity V11 of the first water flow group 521 a is faster and the flow velocity V12 of the second water flow group 522a is slower, the first water flow group 521 a can catch up with the second water flow group 522a at the impingement position or on the nozzle 410 side of the impingement position. On the other hand, in the case where the flow velocity V11 of the first water flow group 521a is slower and the flow velocity V12 of the second water flow group 522a is faster, the first water flow group 521a cannot catch up with the second water flow group 522a before the impingement position.

[0315] However, whether the first water flow group 521a can catch up with the second water flow group 522a is not determined simply by the flow velocity V11 of the first water flow group 521 a and the second water flow group 522a. As described above, the generation of the first water flow group 521 a is started simultaneously with the timing at which voltage is applied to the pulsation generating means 470. The generation of the second water flow group 522a is started simultaneously with the timing at which application of voltage to the pulsation generating means 470 is stopped. Thus, the timing at which the first jetting water 501 and the second jetting water 502 are jetted from the nozzle 410 depends on the on-time of the voltage pulse. Accordingly, whether the first water flow group 521 a can catch up with the second water flow group 522a is determined by e.g. the flow velocity difference between the flow velocity V11 of the first water flow group 521 a and the second water flow group 522a, the timing at which the first jetting water 501 and the second jetting water 502 are jetted from the nozzle 410, and the distance from the jetting hole 411 of the nozzle 410 to the impingement position.

[0316] Thus, in this example, the water force adjusting means 406 sets the period of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the on-time (duty cycle) of the voltage pulse. Accordingly, the water force adjusting means 406 can change the timings at which the first water flow group 521 a and the second water flow group 522a impinge on the human private parts. For instance, by appropriately controlling the on-time (duty cycle) of the voltage pulse, as shown in FIG. 32, the water force adjusting means 406 can cause the first water flow group 521 a and the second water flow group 522a to impinge on the human private parts at generally equal timings.

[0317] As described above, in this example, as a result, the first jetting water 501 and the second jetting water 502 are alternately jetted from the nozzle 410. This can cause the user to feel the water as continuous jetting water free from an emptied hollow portion. Thus, at a small flow rate, the feeling of volume can be provided, and the washing power can be ensured. Furthermore, a wide range can be washed gently and quickly at once.

[0318] In this example, the frequency of the voltage pulse applied to the pulsation generating means 470 is e.g. approximately 70 Hz. In the case where the first water flow group 521 a catches up with the second water flow group 522a at the impingement position, the on-time of the voltage pulse is e.g. approximately 3.25 milliseconds (ms). Thus, in this case, the duty cycle is e.g. approximately 23.2%. In the case where the first water flow group 521 a cannot catch up with the second water flow group 522a before the impingement position, the on-time of the voltage pulse is e.g. approximately 1.87 ms. Thus, in this case, the duty cycle is e.g. approximately 13.3%. The amount of water supplied to the water force adjusting means 406 is constant at e.g. approximately 430 milliliters/min (ml/min).

[0319] FIG. 33 is a plan schematic view for describing liquid drops passing near the impingement position of this example.

[0320] FIG. 34 is a graph illustrating the number of liquid drops in the case where the first water flow group cannot catch up with the second water flow group before the impingement position.

[0321] FIG. 35 is a graph illustrating the number of liquid drops in the case where the first water flow group catches up with the second water flow group at the impingement position.

[0322] In this example, the number of liquid drops is considered in a prescribed range (hereinafter referred to as "impingement front-back range" for convenience of description) 610 before and after the impingement position, i.e., a prescribed range from the nozzle 410 side to the side opposite from the nozzle 410 as viewed from the impingement position. The impingement front-back range 710 is a range of e.g. approximately ±10 millimeters (mm) as viewed from the impingement position.

[0323] FIG. 34 illustrates the number of liquid drops in the impingement front-back range 710 in the case where the first water flow group 521 a cannot catch up with the second water flow group 522a before the impingement position. The "number of liquid drops" refers to the number of first granular water flows 521 included in the first water flow group 521 a or the number of second granular water flows 522 included in the second water flow group 522a. FIG. 35 illustrates the number of liquid drops in the impingement front-back range 710 in the case where the first water flow group 521a catches up with the second water flow group 522a at the impingement position.

[0324] As shown in FIGS. 34 and 35, the total number of liquid drops in the impingement front-back range 710 in the case where the first water flow group 521a catches up with the second water flow group 522a at the impingement position (see FIG. 35) is larger than the total number of liquid drops in the impingement front-back range 710 in the case where the first water flow group 521 a cannot catch up with the second water flow group 522a before the impingement position (see FIG. 34). The "total number of liquid drops" refers to the total of the number of first granular water flows 521 included in the first water flow group 521a and the number of second granular water flows 522 included in the second water flow group 522a.

[0325] Accordingly, the amount of water in the impingement front-back range 710 in the case where the first water flow group 521a catches up with the second water flow group 522a at the impingement position is larger than the amount of water in the impingement front-back range 710 in the case where the first water flow group 521 a cannot catch up with the second water flow group 522a before the impingement position. Thus, by appropriately controlling the on-time (duty cycle) of the voltage pulse, the water force adjusting means 406 can increase the impinging water force at the human private parts. The water force adjusting means 406 sets the period of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the on-time (duty cycle) of the voltage pulse. Accordingly, as described above with reference to FIG. 29, even without changing the amount of water supplied to the water force adjusting means 406, the water force can be adjusted while ensuring the washing power and maintaining the feeling of volume.

[0326] Next, an alternative example of the operation of the water force adjusting means 406 is described with reference to the drawings.

[0327] FIGS. 36A to 36C are timing charts for describing the alternative example of the operation of the water force adjusting means.

[0328] Here, FIG. 36A is a graph illustrating voltage pulses applied to the pulsation generating means of this example. FIG. 36B is a graph illustrating the amount of water passing on the downstream side of the pulsation generating means. FIG. 36C is a graph illustrating the amount of water of the first water flow group and the second water flow group in the third period.

[0329] The water force adjusting means 406 of this example includes a pulsation generating means 470. In this example, the water force adjusting means 406 sets the on-time of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the period of the voltage pulse applied to the pulsation generating means 470. As shown in FIG. 36A, the first period T11 is shorter than the second period T12 (T11<T12). The second period T12 is shorter than the third period T13 (T12<T13).

[0330] Because the on-time of the voltage pulse is constant, the displacement to the Y direction (downstream side) of the plunger 472 is constant even if the period of the voltage pulse is varied. Thus, as shown in FIGS. 36A and 36B, the amount of water pressurized and accelerated by the plunger 472 is constant. The amount of water of the first water flow group 521 a is constant even if the period of the voltage pulse is varied. Furthermore, the flow velocity of the first water flow group 521 a is constant even if the period of the voltage pulse is varied.

[0331] For a longer period of the voltage pulse, the amount of water passing on the downstream side of the pulsation generating means 470 per period increases. Thus, as shown in FIG. 36C, for a longer period of the voltage pulse, the amount of water of the second water flow group 522a increases while the amount of water of the first water flow group 521 a is constant.

[0332] The generation of the first water flow group 521 a (or first jetting water 501) is started simultaneously with the timing at which voltage is applied to the pulsation generating means 470. The generation of the second water flow group 522a (or second jetting water 502) is started simultaneously with the timing at which application of voltage to the pulsation generating means 470 is stopped. Thus, the timing at which the first jetting water 501 and the second jetting water 502 are jetted from the nozzle 410 depends on the off-time of the voltage pulse. Accordingly, whether the first water flow group 521a can catch up with the second water flow group 522a is determined by e.g. the timing at which the first jetting water 501 and the second jetting water 502 are jetted from the nozzle 410, and the distance from the jetting hole 411 of the nozzle 410 to the impingement position.

[0333] Thus, in this example, the water force adjusting means 406 sets the on-time of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the period of the voltage pulse applied to the pulsation generating means 470. Accordingly, the water force adjusting means 406 can change the timings at which the first jetting water 501 and the second jetting water 502 are jetted from the nozzle 410. Thus, the water force adjusting means 406 can change the timings at which the first water flow group 521a and the second water flow group 522a impinge on the human private parts. For instance, by appropriately controlling the period of the voltage pulse applied to the pulsation generating means 470, the water force adjusting means 406 can cause the first water flow group 521a and the second water flow group 522a to impinge on the human private parts at generally equal timings.

[0334] Furthermore, for a longer off-time of the voltage pulse, the amount of water of the second water flow group 522a increases. Thus, the number of liquid drops in the impingement front-back range 710 (see FIG. 33) increases. Accordingly, for a longer off-time of the voltage pulse, the impinging water force at the human private parts increases. The water force adjusting means 406 sets the on-time of the voltage pulse applied to the pulsation generating means 470 to be constant, and changes the period of the voltage pulse applied to the pulsation generating means 470. Accordingly, even without changing the amount of water supplied to the water force adjusting means 406, the water force can be adjusted while ensuring the washing power and maintaining the feeling of volume.

[0335] In this example, the amount of water supplied to the water force adjusting means 406 is constant at e.g. approximately 430 ml/min (approximately 7.12 ml/sec). In this case, if the frequency of the voltage pulse applied to the pulsation generating means 470 is e.g. approximately 70 Hz, the amount of water passing on the downstream side of the pulsation generating means 470 per period is approximately 0.102 ml/period. If the frequency of the voltage pulse applied to the pulsation generating means 470 is e.g. approximately 90 Hz, the amount of water passing on the downstream side of the pulsation generating means 470 per period is approximately 0.079 ml/period. Thus, if the frequency of the voltage pulse applied to the pulsation generating means 470 is increased by approximately 20 Hz, the amount of water passing on the downstream side of the pulsation generating means 470 per period is increased by 0.023 ml.

[0336] Next, a further alternative embodiment of this invention is described.

[0337] The investigation on the feeling of volume (feeling of fullness) performed by the inventor is described with reference to the drawings.

[0338] FIG. 37 is a schematic view for describing a method for measuring the vibration state of the impingement part by the water.

[0339] FIGS. 38A and 38B are graphs illustrating an example of the measurement result of the vibration state of the impingement part by the water.

[0340] Here, FIG. 38A is a graph illustrating an example of the measurement waveform. FIG. 38B is a graph illustrating an example of the result of Fourier transforming the graph shown in FIG. 38A.

[0341] The inventor measured the vibration state of the impingement part by the water 500 jetted from the nozzle 410. Specifically, as shown in FIG. 37, a jetting water receiving tray 610 was placed at the position corresponding to the human private parts of a user seated on the toilet seat 200. The jetting water receiving tray 610 is shaped like a square 10 millimeters (mm) on a side. Furthermore, a force sensor 620 for measuring the force experienced by the jetting water receiving tray 610 was placed. The force sensor 620 used in this measurement is "KISTLER Model 9207". The force sensor 620 converts the force experienced by the jetting water receiving tray 610 into an electrical signal, and outputs the electrical signal to a measuring instrument 630 such as a spectrum analyzer.

[0342] An example of the waveform measured by the measuring instrument 630 is as shown in FIG. 38A. More specifically, the horizontal axis of the graph shown in FIG. 38A represents time (seconds, s). The vertical axis of the graph shown in FIG. 38A represents voltage (volts, V). In this measurement, the flow rate of the water 500 jetted from the nozzle 410 is approximately 430 ml/min. Furthermore, pulsation is applied to the water 500 jetted from the nozzle 410. Here, the term "pulsation" used herein refers to pressure variation caused by the pulsation generating means described later. That is, the pulsation generating means described later is a device for varying the pressure of water in the flow channel. This will be described later in detail.

[0343] An example of the result of Fourier transforming the graph shown in FIG. 38A is as shown in FIG. 38B. More specifically, the horizontal axis of the graph shown in FIG. 38B represents frequency (hertz, Hz). The vertical axis of the graph shown in FIG. 38B represents amplitude. This indicates that the graph shown in FIG. 38A (an example of the waveform measured by the measuring instrument 630) significantly contains the component of a frequency of approximately 70 Hz and the components of multiples thereof. Thus, the inventor measured the vibration state of the impingement part by the water of different jetting modes, and investigated the relationship between the difference in the feeling of fullness and the difference in the vibration state.

[0344] FIGS. 39A and 39B are graphs for describing the relationship between the feeling of fullness and the presence or absence of pulsation.

[0345] Here, FIG. 39A is a graph illustrating the result of Fourier transforming the measurement waveform in the case of applying pulsation to the water. FIG. 39B is a graph illustrating the result of Fourier transforming the measurement waveform in the case of applying no pulsation to the water.

[0346] In this investigation, the flow rate of the water 500 jetted from the nozzle 410 is approximately 430 ml/min. As the result of hearing by the inventor, the jetting mode of the graph shown in FIG. 39A was rated as having the feeling of fullness. On the other hand, the jetting mode of the graph shown in FIG. 39B was rated as slightly having the feeling of fullness. That is, the number of ratings of having the feeling of fullness for the jetting mode of the graph shown in FIG. 39A was larger than the number of ratings of having the feeling of fullness for the jetting mode of the graph shown in FIG. 39B.

[0347] As shown in FIG. 39A, in the jetting mode with a larger number of ratings of having the feeling of fullness, the measurement waveform of the force experienced by the jetting water receiving tray 610 contains more significantly the component of a frequency of approximately 70 Hz and the components of multiples thereof. On the other hand, as shown in FIG. 39B, in the jetting mode with a smaller number of ratings of having the feeling of fullness, the measurement waveform of the force experienced by the jetting water receiving tray 610 contains less significantly the component of a frequency of approximately 70 Hz and the components of multiples thereof.

[0348] Thus, the difference in the feeling of fullness is related to the presence or absence of pulsation applied to the water. If pulsation is applied to the water, a larger feeling of fullness can be provided. Furthermore, the difference in the feeling of fullness is related to the magnitude of the amplitude of the component of a frequency of approximately 70 Hz and the components of multiples thereof.

[0349] FIGS. 40A and 40B are a table and a graph for describing the relationship between the feeling of fullness and the frequency.

[0350] Here, FIG. 40A is a table for describing the relationship between the feeling of fullness and the frequency. FIG. 40B is a graph illustrating the relationship between the frequency and the jetting weight.

[0351] In this investigation, the frequency of the waveform of the voltage supplied to the pulsation generating means described later was set to approximately 50 Hz, approximately 71.4 Hz, approximately 100 Hz, and approximately 150 Hz to apply pulsation to the water. The time for supplying the voltage was set to approximately 3.25 milliseconds (ms). The flow rate of the water 500 jetted from the nozzle 410 was set to approximately 200 ml/min and approximately 130 ml/min.

[0352] Here, if the frequency of the waveform of the voltage supplied to the pulsation generating means described later is changed, then the frequency of vibration of the impingement part, or specifically, the frequency of vibration of the skin where the water impinges, is changed. That is, changing the frequency of the waveform of the voltage supplied to the pulsation generating means described later corresponds to changing the frequency of vibration of the impingement part. The frequency of vibration of the impingement part can be measured by the measuring method described above with reference to FIGS. 37 to 38B.

[0353] As shown in FIG. 40A, as the result of hearing by the inventor, in the case where the flow rate of the water 500 jetted from the nozzle 410 is approximately 130 ml/min, for a frequency of approximately 50 Hz, the following rating was obtained. Because the frequency is relatively low, it is felt that the water is not continuous jetting water (the feeling of interruption is slightly felt). However, the water has a feeling of fullness, and the impact of the water 500 is heavy.

[0354] In the rating obtained for a frequency of approximately 71.4 Hz, the water has a feeling of fullness, and the impact of the water 500 is slightly heavy. I n the rating obtained for a frequency of approximately 100 Hz, the water has a feeling of fullness, and the impact of the water 500 is less heavy. As shown in FIG. 40B, these ratings have generally the same trend as the change of jetting weight.

[0355] More specifically, the horizontal axis of the graph shown in FIG. 40B represents frequency (Hz). The vertical axis of the graph shown in FIG. 40B represents jetting weight (millinewtons, mN). In this investigation, the jetting weight refers to the force (weight) experienced by the jetting water receiving tray 610. That is, the jetting weight can be measured by the force sensor 620. With the increase of frequency, the jetting weight decreases. Like this decreasing trend of the jetting weight, with the increase of frequency, the rating of the impact of the water 500 as being heavy decreases. Furthermore, as illustrated in the graph of the result of Fourier transforming the measurement waveform (see FIG. 40A), with the increase of frequency, the amplitude of the component of a frequency of approximately 70 Hz and the components of multiples thereof decreased.

[0356] Next, in the rating obtained for a frequency of approximately 150 Hz, the water has less feeling of fullness, and the impact of the water 500 is light. Thus, the flow rate of the water 500 jetted from the nozzle 410 was set to approximately 200 ml/min. Then, as shown in FIG. 40A, the amplitude of the component of a frequency of approximately 70 Hz and the components of multiples thereof increased. Furthermore, as shown in FIG. 40B, the jetting weight increased. Nevertheless, as in the case of a flow rate of approximately 130 ml/min, in the obtained rating, the water has less feeling of fullness, and the impact of the water 500 is light.

[0357] Thus, the difference in the feeling of fullness is related to the frequency of the waveform of the voltage supplied to the pulsation generating means described later or the frequency of vibration of the impingement part (specifically, the frequency of vibration of the skin where the water impinges). Even if the frequency of the waveform of the voltage supplied to the pulsation generating means described later or the frequency of vibration of the impingement part is set to a frequency higher than 100 Hz, in the obtained rating, the water has less feeling of fullness, and the impact of the water 500 is light. Furthermore, while the feeling of interruption of the jetting water can be dissolved, the feeling of vibration cannot be provided. This may cause the danger of failing to provide the feeling of vibration, and failing to provide an adequate feeling of fullness required for bottom washing. On the other hand, if the frequency of the waveform of the voltage supplied to the pulsation generating means described later or the frequency of vibration of the impingement part is set to a frequency lower than 50 Hz, in the obtained rating, the water has a feeling of fullness, and the impact of the water 500 is heavy. However, the rating that the feeling of interruption is felt is obtained. Thus, if the frequency of the waveform of the voltage supplied to the pulsation generating means described later or the frequency of vibration of the impingement part is set to 50 Hz or more and 100 Hz or less, in the obtained rating, the water has a feeling of fullness, and the impact of the water 500 is heavy. That is, if the frequency of the waveform of the voltage supplied to the pulsation generating means described later or the frequency of vibration of the impingement part is set to 50 Hz or more and 100 Hz or less, an adequate feeling of fullness required for bottom washing can be provided.

[0358] The embodiments of the invention have been described above. However, the invention is not limited to the above description. Those skilled in the art can suitably modify the above embodiments, and such modifications are also encompassed within the scope of the invention as long as they include the features of the invention. For instance, the shape, dimension, material, and layout of various components in the jetting means 401, the liquid film thickness expanding means 402, the fracturing means, the pulsation generating means 470 and the like, and the installation configuration of the nozzle 410, the nozzle body 420, and the throat 430 are not limited to those illustrated, but can be suitably modified.

[0359] Furthermore, various components in the above embodiments can be combined with each other as long as technically feasible. Such combinations are also encompassed within the scope of the invention as long as they include the features of the invention.

[Industrial Applicability]

[0360] This invention provides a sanitary washing apparatus capable of washing the washing area gently and quickly at once by uniform impingement of water on a larger washing area than the conventional bottom washing. In bottom washing of a user in bad physical condition, the sanitary washing apparatus can realize a high feeling of water volume required for the act of bottom washing without unnecessarily causing discomfort such as a strong feeling of stimuli and a feeling of being swept in the central part. Furthermore, the sanitary washing apparatus can suppress scattering of water to the outside of the desired washing area.

[Reference Signs List]

[0361] 

100

sanitary washing apparatus

200

toilet seat

300

toilet lid

400

casing

401

jetting means

402

liquid film thickness expanding means

404

seating sensor

406

water force adjusting means

410

nozzle

411

jetting hole

420

nozzle body

421

nozzle body flow channel

423

swirling chamber

423e

large diameter inner peripheral wall

423f

inclined inner peripheral wall

424

protrusion

425

communication channel

426

jetting hole

430

throat

431

throat flow channel

432

taper part

433

jetting hole

435

spiral groove

470

pulsation pump

471

cylinder

472

plunger

473

check valve

474

pulsation generating coil

475

downstream side

476

return spring

477

buffer spring

500

water

501

first jetting water

502

second jetting water

510

hollow-conic-shape jetting water

511

first hollow-conic-shape jetting water

512

second hollow-conic-shape jetting water

520

granular water flows

521

first granular water flows

521

a first water flow group

522

second granular water flows

522a

second water flow group

533

jetting hole

610

etting water receiving tray

620

force sensor

630

measuring instrument

710

impingement front-back range

800

toilet stool

801

bowl

Claims

1. A sanitary washing apparatus for jetting water from a jetting hole of a nozzle used in bottom washing toward human private parts, the apparatus comprising:

jetting means configured to jet water in a hollow conic shape from the jetting hole;

fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to fill a hollow portion of the water jetted in the hollow conic shape with the granulated water flows before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts; and

liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means.

2. The apparatus according to claim 1, wherein the liquid film thickness expanding means makes the thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker by making flow velocity of the water flowing out of the liquid film thickness expanding means slower than flow velocity of the water flowing into the liquid film thickness expanding means.

3. The apparatus according to claim 2, wherein the liquid film thickness expanding means makes the flow velocity of the water slower by making resistance applied to the water flowing out of the liquid film thickness expanding means larger than resistance applied to the water flowing into the liquid film thickness expanding means.

4. The apparatus according to claim 2, wherein
the liquid film thickness expanding means is a throat formed in a tubular shape and having a flow channel inside, and
the throat receives the water jetted in the hollow conic shape from the jetting means at an inner wall of the flow channel and slows down the flow velocity of the water by a frictional force occurring when the water passes along the inner wall of the flow channel.

5. The apparatus according to claim 4, wherein a portion between the jetting means and the throat is opened to atmosphere.

6. The apparatus according to claim 2, wherein
the nozzle includes:

a jetting port configured to jet hollow-conic-shape water formed by a swirling flow; and

an annular part configured to receive the hollow-conic-shape water jetted from the jetting port, to decelerate the water while maintaining a state of the liquid film by passing the water along an inner wall, and to make the thickness of the liquid film of the water thicker, and

the jetting hole configured to jet the water passed through the annular part in the hollow conic shape is provided on downstream side in the annular part, and the liquid film of the hollow-conic-shape water jetted from the jetting hole is fractured.

7. A sanitary washing apparatus used in bottom washing, comprising:

a nozzle including a jetting hole and configured to jet water from the jetting hole toward human private parts,

the nozzle being configured to jet:

first jetting water including a flow toward a central part of the human private parts after impinging on an outer peripheral part of the human private parts, and

second jetting water including a flow toward the outer peripheral part of the human private parts after impinging on the central part of the human private parts, and

impinging water force at the human private parts of the first jetting water being larger than impinging water force at the human private parts of the second jetting water.

8. The apparatus according to claim 7, wherein flow velocity of the first jetting water is faster than flow velocity of the second jetting water.

9. The apparatus according to claim 7, wherein the first jetting water includes ring-shaped jetting water, and the second jetting water includes solid jetting water.

10. The apparatus according to claim 7, wherein the first jetting water and the second jetting water are alternately jetted from the jetting hole.

11. The apparatus according to claim 10, further comprising:

pulsation generating means configured to provide pulsation to the water jetted from the jetting hole to alternately jet the first jetting water and the second jetting water.

12. A sanitary washing apparatus for bottom washing by jetting water from a jetting hole of a nozzle toward human private parts, the apparatus comprising:

jetting means configured to jet water in a hollow conic shape from the jetting hole;

fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to pour the granulated water flows into a hollow portion of the water jetted in the hollow conic shape before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts;

liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means; and

fracturing position varying means configured to periodically vary position of fracturing the liquid film of the water jetted in the hollow conic shape from the jetting hole.

13. The apparatus according to claim 12, wherein the fracturing position varying means changes flow velocity of the water jetted from the jetting hole.

14. The apparatus according to claim 13, wherein
the water jetted in the hollow conic shape from the jetting hole is divided into at least one of first jetting water including ring-shaped jetting water and second jetting water including solid jetting water by the fracturing position varying means and impinges on the human private parts, and
the fracturing position varying means alternately divides the water jetted in the hollow conic shape from the jetting hole into the first jetting water and the second jetting water.

15. The apparatus according to claim 14, wherein
position where liquid film of the first jetting water is fractured is located on the human private parts side of position where liquid film of the second jetting water is fractured, and
the first jetting water impinges on the human private parts in a state of maintaining the ring-shaped jetting water.

16. The apparatus according to claim 13, wherein a plurality of the granulated water flows fractured by the fracturing position varying means and having mutually different flow velocities independently impinge on the human private parts.

17. A sanitary washing apparatus for bottom washing by jetting water from a jetting hole of a nozzle toward human private parts, the apparatus comprising:

jetting means configured to jet water in a hollow conic shape from the jetting hole;

fracturing means configured to generate granulated water flows by fracturing a liquid film of the water jetted in the hollow conic shape to pour the granulated water flows into a hollow portion of the water jetted in the hollow conic shape before the water jetted in the hollow conic shape from the jetting hole impinges on the human private parts; and

liquid film thickness expanding means provided on downstream side of the jetting means and on upstream side of the jetting hole and configured to make thickness of the liquid film of the water jetted in the hollow conic shape from the jetting hole thicker than thickness of a liquid film of the water jetted in the hollow conic shape from the jetting means,

the granulated water flows including a first water flow group and a second water flow group having a smaller particle diameter and a slower flow velocity than the first water flow group, and

the first water flow group and the second water flow group independently impinging on the human private parts.

18. The apparatus according to claim 17, wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

19. The apparatus according to claim 17, wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

20. The apparatus according to claim 17, wherein the first water flow group and the second water flow group are alternately generated from the granulated water flows.

21.  The apparatus according to claim 17, wherein time interval at which the first and second water flow groups impinge on the human private parts is a time interval at which a human feels the water as continuous jetting water.

22. The apparatus according to claim 21, wherein
surface of the human private parts is vibrated in accordance with the time interval, and
frequency of the vibration of the surface is 50 hertz or more and 100 hertz or less.

23. The apparatus according to claim 21, further comprising:

pulsation generating means configured to provide pulsation to the water jetted from the jetting hole to produce the first water flow group and the second water flow group,

wherein frequency of the pulsation provided by the pulsation generating means is 50 hertz or more and 100 hertz or less.

24. The apparatus according to claim 21, wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

25. The apparatus according to claim 21, wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

26. The apparatus according to claim 17, further comprising:

water force adjusting means capable of adjusting water impinging force of the water at the human private parts,

wherein the water force adjusting means changes timing at which the first water flow group and the second water flow group impinge on the human private parts in accordance with water force specified by a user.

27. The apparatus according to claim 26, wherein the first water flow group impinges on an outer peripheral part of the human private parts, and the second water flow group impinges on a central part of the human private parts.

28. The apparatus according to claim 26, wherein amount of water of the first water flow group at the human private parts is larger than amount of water of the second water flow group at the human private parts.

29. The apparatus according to claim 26, wherein the first water flow group and the second water flow group are alternately generated from the granulated water flows.

30. The apparatus according to claim 26, wherein
the water force adjusting means further includes pulsation generating means configured to provide pulsation to the water jetted from the jetting hole, and changes the timing in accordance with the water force by adjusting period of a voltage pulse applied to the pulsation generating means.

31. The apparatus according to claim 26, wherein
the water force adjusting means further includes pulsation generating means configured to provide pulsation to the water jetted from the jetting hole, and changes the timing in accordance with the water force by adjusting on-time of a voltage pulse applied to the pulsation generating means.

Drawing