WATER-FLUSHED TOILET PAN

Abstract

 The invention concerns a water-flushed toilet pan with a rimless toilet bowl (1), with the supply of flush water in its rear top part, which includes an inlet pipe (8) terminated with an inlet hole (7) and a channel (9) located behind it, terminated with an outlet (10). The outlet hole (2) to the trap (3) is located in the bottom part of the bowl (1). The toilet pan has the first central plane (A-A), which, when the toilet pan is assembled, is parallel to the installation wall and abstractly divides the toilet pan through the centre of the outlet hole (2) into the front and rear section, as well as a perpendicular second central plane (C-C), which abstractly divides the toilet pan through the centre of the outlet hole (2) into the right and left section. The toilet bowl (1) has a top edge (6) that is a fragment of the top inner surface of the toilet bowl (1), located directly below the external cover (5) and having an approximately elliptical shape, formed as a flat circle whose walls are essentially vertical. The outlet hole (2) is shifted within that ellipse towards the rear of the toilet pan. The outlet (10) of the channel (9) is positioned asymmetrically to the second central plane (C-C), on the right or left side of the bowl (1), in its upper area, so that flush water flows into it falling first on the rear section of the top edge (6), in a direction essentially horizontal and tangential with the inner surface of the bowl (1), and then performs rotary motion inside it. The toilet pan is characterised in that the internal shape of the toilet bowl (1), excluding the location of the outlet (10), has a symmetric shape relative to the second central plane (C-C), and that the bowl (1) on its internal side, at the level of the outlet (10) and directly below the top edge (6), has an upper threshold (12) formed as a bulge running horizontally around the inner surface of the toilet bowl (1), whereas it protrudes slightly less in the rear area of the toilet bowl (1) than in other areas thereof.

Description

Technical Field

[0001] This invention concerns a water-flushed toilet pan with a toilet bowl.

Prior Art

[0002] Water-flushed toilet pans with a toilet bowl supplied with flush water and connected to a sewage drain are commonly known and used. Water-flushed toilet pans normally have a body with a pan-shaped bowl with an opening in the top part, wherein the bowl is connected to a drain of used sewage, usually using a water trap. Toilet pans are normally made of ceramic material.

[0003] The flushing of a toilet pan with water is used to carry out two operations: to clean the toilet bowl's inner surface and to carry the used water along with impurities through the trap to the drain. In conventional toilet bowls, normally the inner top edge of the bowl has a so-called flush rim, which has the form of a circumferential channel provided with holes or a slot, which acts as a ring-shaped shower. Flushing is performed by directing a part of water into the hollow rim, from which it is drained into the bowl through a narrow slot or a series of holes arranged at a certain space, which enables the washing of the inner surface of the bowl. Higher water volumes may be directed at specific points in the bowl, for example downwards onto the front and rear surfaces of the pan (e.g. through larger holes made therein). The part of the rim with the channel may be made either as a separate hollow section and added to the bowl during production or as an integral part of the bowl, during the production process. In either case, it usually has the form of a collar; it protrudes inside so that it hangs down from the top part of the pan around the whole or a part of its rim. From prior art we also know toilet pans with other flushing mechanisms, for example such that use a rotary (approximately swirling) motion of water flux induced by the introduction of water flux tangential with the bowl, as well as toilet pans which, in place of the hanging collar, have a hollow groove/channel that surrounds the inner surface of the bowl.

[0004] The bowl arrangement that uses a conventional, annular flush rim (usually with a collar) as well as any type of hollow channels or grooves, implies hard-to-reach areas within the bowl, which have the form of overhangs or concavities, which significantly hinders or sometimes even prevents effective cleaning of the toilet bowl. The channel in the flush rim is completely inaccessible and impossible to be cleaned. Such a design therefore makes conventional toilet pans particularly susceptible to contamination and deposits in the form of scale. Furthermore, since the water flux pressure on the bowl's walls is too weak, the flushing of bowls with such a structure is relatively ineffective and, in consequence, high volumes of water must be used. In addition, water flowing down on the bowl's walls reaches the trap with an insufficient momentum, which makes it possible that a single flushing cycle will not move all impurities into the drain.

[0005] A water-flushed toilet pan with a symmetric internal shape of the bowl and a conventional flush rim is disclosed, for example, in the description in British application GB 685960 A.

[0006] Patent GB 2045311 B proposes a toilet bowl with an essentially smooth internal contour, which has no collar around its rim. The rim of that bowl is, however, surrounded by a hollow water channel provided with one or more flush holes. The hollows made in that rim bowl, as in a conventional collar, also make it difficult to maintain the toilet pan clean, as they can collect impurities and scale.

[0007] From the description in French application FR 2744744 A, we know a water-flushed toilet pan whose bowl has an asymmetric internal shape and is provided with a conventional flush rim. The outlet of that toilet bowl is shifted relative to the symmetry axis of its rim. The internal wall of the bowl consists of spherical or conical segments interlinked with edges, with their joints slightly lifted so that the bowl can be flushed and emptied at the same time.

[0008] The description in British application GB 2431937 A discloses a toilet pan with a bowl having a symmetric internal shape, which does not have a conventional annular flush rim. In that solution, flush water is directed to the pan through an inlet pointing downwards and through inlets pointing at the top part of the bowl's inner surface (approximately in parallel to the plane of the bowl's opening). Flush water escapes from the pre-chamber located directly downstream of the inlet that supplies water from pipelines to the toilet pan that is covered (closed) by a fragment of its rim, and is directed simultaneously to the left and right side of the bowl, tangentially with its internal wall, and then the two fluxes move on the internal wall of the bowl and hit each other in its front part.

[0009] Patent EP 2604761 B1 constitutes the closest prior art to the developed solution. That document concerns a water-flushed toilet pan which does not have a conventional flush rim, whose flush stream is asymmetric, and which is provided with a bowl having an asymmetric shape. The essence of the solution disclosed herein is that the shape of the toilet bowl is asymmetric to the vertical central plane, and consequently the internal shape of the bowl determines the route of flush water flux, i.e. it forces it to move in a specified way: circumferentially at the internal wall of the bowl. The route of flush water flux on one side of the central plane is located lower than on the other side, and as a result the water's rotary motion is overlaid with a downward motion dependent on the internal shape of the bowl, and thus the speed of flush water is increased by the vertical component directed downwards, caused by the internal shape of the bowl.

The Essence of the Invention

[0010] Thus, the described prior art contains various solutions of a technical issue regarding how to provide a water-flushed toilet pan that ensures the fastest possible flushing of water downwards in the bowl with the possibly most precise cleaning of its surface. Unexpectedly, it turned out that the issue can be solved even more effectively with a new structure of a toilet pan unknown in prior art, which is an alternative to the structures described above, especially to those described in GB 2431937 A and EP 2604761 B1. Document GB 2431937 A discloses a toilet pan without a conventional flush rim, whose bowl has a symmetric internal shape, and in which water is introduced into the bowl symmetrically (through a symmetric inlet), to the left and right side at the same time. Patent EP 2604761 B1 discloses a toilet pan without a conventional flush rim, which has a bowl whose shape is asymmetric to the vertical central plane, and where water is introduced into the bowl asymmetrically. A solution alternative to the mentioned technical issue is provided by a toilet pan according to claim 1, whose structure does not include a flush rim (i.e. includes a rimless bowl), which supplies water into the bowl asymmetrically but at the same time has a symmetric bowl. That structure will be presented more specifically further in this description.

[0011] As it unexpectedly turned out during experimental tests carried out by the authors of this invention, the pan being most effective in terms of the speed of bringing water down in the toilet bowl is a pan that is symmetric to the vertical central plane and asymmetrically introduces water into the bowl; water is introduced tangentially with the inner surface of the bowl, in its top part, at the rear of the bowl, and directed rightwards or leftwards. Such a bowl allows for much faster and more dynamic bringing of water down than in an asymmetric pan, which is known from, for example, the aforesaid patent EP 2604761 B1. Such a symmetric shape of the pan makes it possible to generate rotary motion of flush water in the toilet bowl as well as to achieve a significant vertical component of the speed of water flux motion downwards to the outlet leading to the trap. Flush water in a bowl with such a shape moves with a high momentum, which additionally improves its cleaning properties, as it can separate impurities from the bowl's internal walls with a higher strength.

[0012] The authors of this invention have also found out that for more effective flushing, particularly with a low volume of flush water, apart from a clear vertical speed component, it is also important to ensure adequately long retention of water in the bowl and to direct the water in such a way to clean the bowl's internal walls as precisely as possible, which can be achieved in this invention owing to the presence of one or more (preferably two) thresholds in the bowl. With their shape, the thresholds prolong the rotary motion of water flux, and thus enable efficient use of the energy of flush water flux. The said thresholds form areas on the bowl's inner surface where vertical inclination of such inner surface is lower than in the areas located directly above and below them. Colloquially speaking, the areas are "more horizontal". Using a precise language of mathematics, the gradient of vertical inclination of the bowl's inner surface in these areas has a locally lower value than in the areas located directly above and below them. Technically (structurally), the threshold has the form of a bulge that runs horizontally around the inner surface of the toilet bowl. The thresholds run horizontally, essentially around the entire bowl. As the entire inner surface of the bowl below the flush water inlet, the thresholds are symmetric (left side to right side) relative to the vertical central plane.

[0013] The toilet pan according to the present invention has a bowl without a flush rim, which will be further referred to as a rimless bowl. The internal shape of such a bowl does not have a flush rim, that is a circumferential flush water channel whose inlet holes used for the inflow of water into the bowl are pointed downwards.

[0014] The structure according to the present invention, which combines the absence of rim, asymmetric introduction of flush water into the rim and a symmetric bowl, is not only novel but also non-obvious in view of prior art. In particular, it cannot be obtained by combining the solutions described in GB 2431937 A and EP 2604761 B1 referred to above.

[0015] The water-flushed toilet pan with a rimless toilet bowl, with the supply of flush water in the rear top part of the toilet bowl, which includes an inlet pipe terminated with an inlet hole and a channel located behind it, terminated with an outlet, wherein the outlet hole to the trap is located in the bottom part of the toilet bowl, the toilet pan having the first central plane A-A, which, when the toilet pan is assembled, is parallel to the installation wall and abstractly divides the toilet pan through the centre of the outlet hole into the front and rear section, which rear section adjoins the installation wall, as well as a perpendicular second central plane C-C, which abstractly divides the toilet pan through the centre of the outlet hole into the right and left section, and wherein the toilet bowl has a top edge that is a fragment of the top inner surface of the toilet bowl, located directly below the external cover and having an approximately elliptical shape, formed as a flat circle whose walls are essentially vertical, on which top edge an external cover is installed, and the outlet hole is shifted within that ellipse towards the rear of the toilet pan, and wherein the outlet of the channel is positioned asymmetrically to the second central plane C-C, on the right or left side of the toilet bowl, in its upper area, so that flush water flows into the toilet bowl falling first on the rear section of the top edge, in a direction essentially horizontal and tangential with the inner surface of the toilet bowl, and then performs rotary motion inside the toilet bowl, according to the invention is characterised in that

the internal shape of the toilet bowl, excluding the location of the outlet, has a symmetric shape relative to the second central plane C-C;

the toilet bowl on its internal side, at the level of the outlet and directly below the top edge, has an upper threshold formed as a bulge running horizontally around the inner surface of the toilet bowl, whereas it protrudes slightly less in the rear area of the toilet bowl than in other areas thereof.

[0016] Preferably, the height of the upper threshold measured vertically is 4 mm, and the width of the upper threshold measured horizontally is 9 mm, whereas the radius of curvature of the upper threshold in normal plane relative to the inner surface of the toilet bowl is 14 mm, and the radius of curvature of the arc between the top edge and the beginning of the upper threshold at the said plane is 20 mm.

[0017] Preferably, the first section of the channel downstream of the inlet hole is directed to the right or left side of the bowl and is slightly bent according to the shape of the top edge, and further has a curve of approximately 180°, so the outlet is located on the right or left side of the toilet bowl but is directed to the opposite side than the said first section of the channel, so to the left or right side, correspondingly.

[0018] Preferably, below the upper threshold but above the level of water surface existing in the pan's operating condition, the toilet bowl has a lower threshold formed as a bulge running around the inner surface of the toilet bowl, whereas it protrudes slightly less in the rear area of the toilet bowl than in other areas thereof.

[0019] Preferably, the lower threshold has a radius of curvature in normal plane relative to the inner surface of the toilet bowl, ranging from 32 to 66 mm.

[0020] Preferably, the lower threshold is located below the halfway between the upper threshold and the level of water surface, preferably at 2/3 of the distance between the upper threshold and the level of water surface.

[0021] Preferably, below the lower threshold, the toilet bowl has a section shaped as a bevelled cone whose diameter is gradually reduced towards the trap.

[0022] Preferably, between the upper threshold and the lower threshold, the toilet bowl is curved and essentially has the shape of a basin.

[0023] Preferably, the bottom of the channel is provided with a compartment formed as a bulge or a step that runs transversely to the length of that channel, between its walls, preferably at the halfway point of the curve of the channel, and more preferably behind the halfway point of the curve of the channel viewed from the inlet hole to the outlet.

[0024] Preferably, the height of the compartment is 4 to 10 mm, preferably 5 mm, and the width of the compartment is 1 to 15 mm, preferably 4 mm.

[0025] Preferably, the cross sectional area of flush water inlet hole is 15.5 to 16.5 cm², preferably 16.04 cm².

[0026] Preferably the cross sectional area of the channel in the part between the inlet hole and the curve is 16 to 17.5 cm², preferably 16.81 cm².

[0027] Preferably, the channel's cross section is flattened, which means it is longer in vertical direction and narrows down more at the outlet.

[0028] Preferably, the channel's cross section is rectangular.

[0029] Preferably, the relation of the height of the vertical outlet to the width of that outlet is 4.0 to 4.12, preferably 4.06.

[0030] Preferably, the height of the outlet is 68 to 74 mm, preferably 71 mm, and the width of the outlet is 17 to 18 mm, preferably 17.5 mm.

[0031] Preferably, the channel has a curve with a radius of curvature of 27 to 40 mm.

[0032] Preferably, the height of the top edge is 66 to 93 mm.

[0033] Preferably, the distance between the first central plane A-A and the point of the toilet bowl most protruding frontwards is 240 mm.

Preferable Effects of the Invention

[0034] The present invention, with the use of rotary/circular motion of water in the bowl, allows for effective cleaning of the bowl surface and, owing to the high momentum of flush water, effective movement of water with impurities into the trap and drain. The structure of the toilet bowl according to the invention additionally allows for significant reduction in the volume of flush water, which is beneficial in terms of economy and the environment. The toilet pan according to the invention is also easy to clean, as it has smooth internal walls that are easily accessible for cleaning, and given its simple design, its production is easy and cheap.

Description of drawing figures

[0035] The subject of the invention will now be presented closer in preferred embodiments, in reference to the attached drawing, wherein Fig. 1 to Fig. 9 show the toilet pan according to the invention with two thresholds, and Fig. 10 to Fig. 17 show the toilet pan according to the invention with one threshold, and wherein:

Fig. 1 is a top view of the toilet pan according to the invention, with marked section planes;

Fig. 2a is a top view of the toilet pan according to the invention without the external cover;

Fig. 2b is a close-up view of a fragment of the channel with a compartment;

Fig. 3 is an oblique view of the toilet pan according to the invention without the external cover;

Fig. 4a schematically shows a section of the toilet pan in A-A plane;

Fig. 4b shows the arrangement of the upper threshold in a section in A-A plane;

Fig. 5 shows a section of the toilet pan in the A-A plane shown in Fig. 4a, with a view on the structural components located outside that plane.

Fig. 6 schematically shows a section of the toilet pan in B-B plane;

Fig. 7 shows a section of the toilet pan in the B-B plane shown in Fig. 6, with a view on the structural components located outside that plane;

Fig. 8 schematically shows a section of the toilet pan in C-C plane;

Fig. 9 shows a section of the toilet pan in the C-C plane shown in Fig. 8, with a view on the structural components located outside that plane;

Fig. 10 is a top view of the toilet pan according to the invention without the external cover;

Fig. 11 is an oblique view of the toilet pan according to the invention without the external cover;

Fig. 12 schematically shows a section of the toilet pan in A-A plane;

Fig. 13 shows a section of the toilet pan in the A-A plane shown in Fig. 12, with a view on the structural components located outside that plane;

Fig. 14 schematically shows a section of the toilet pan in B-B plane;

Fig. 15 shows a section of the toilet pan in the B-B plane shown in Fig. 14, with a view on the structural components located outside that plane;

Fig. 16 schematically shows a section of the toilet pan in C-C plane;

Fig. 17 shows a section of the toilet pan in the C-C plane shown in Fig. 16, with a view on the structural components located outside that plane.

[0036] The drawing uses the following numerical symbols: 1 - toilet bowl, 2 - outlet hole, 3 - trap, 4 - drain, 5 - external cover, 6 - top edge, 7 - inlet hole, 8 - inlet pipe, 9 - channel, 10 - outlet, 11 - protrusion, 12 - upper threshold, 13 - lower threshold, 14 - compartment.

Detailed description of the preferred embodiment

[0037] Below the invention will be presented more specifically based on a preferred embodiment, in reference to the drawing figures.

[0038] The drawing figures generally present a toilet pan with a rimless toilet bowl (without a circumferential flush water channel whose inlet holes used for the inflow of water into the bowl are pointed downwards), made for example of ceramic material. Fig. 1 to Fig. 9 show a toilet pan according to the invention, provided with two water retention thresholds, while Fig. 10 to Fig. 17 show a toilet pan according to the invention, provided with one water retention threshold (the second bulge visible in the drawing is located lower, at the level of water surface, so within the meaning of this invention it is not counted as a threshold retaining water in the bowl).

[0039] Fig. 1 shows a top view on the toilet bowl according to the invention, with marked planes crossing the bowl in specified locations: the first central plane A-A, which crosses the toilet pan horizontally, in parallel to the installation wall (not shown) in the pan's assembled condition, and runs through the centre of the outlet hole 2; plane B-B, which crosses the pan horizontally below plane A-A, outside the outlet hole 2; second central plane C-C, which is perpendicular to the said planes A-A and B-B and crosses the pan vertically, dividing it into two equal sections: right and left. The outlet hole 2 is located in the bottom part of the toilet bowl 1 and leads to the trap 3, which is connected to the rear outlet 4 in a known manner (the trap 3 and the rear outlet 4 are not shown in Fig. 1). In other words, we can say that the outlet hole 2 is the beginning of the trap 3. The toilet bowl 1 has an external cover 5 with a hole having an approximately elliptical shape, and the outlet hole 2 within that ellipse is shifted backwards (towards the rear outlet 4) and located centrally relative to central plane C-C, which is a known solution in toilet bowls. In a non-limiting embodiment, the distance between plane A-A and the point of the toilet bowl 1 most protruding outside (the one most distant from the installation wall, that is: with the external end of the cover 5 located at the front of the pan) is 240 mm. Section plane B-B was chosen arbitrarily to better depict the pan's symmetry. That plane is located in Fig. 1 halfway between plane A-A and the internal end of the cover 5 located at the front of the pan, in the most protruding part, and in this case the distance between plane A-A and plane B-B is 100 mm. However, that plane could be located in any other place between plane A-A and the internal end of the cover 5 at the front of the pan; it is marked only to illustrate that the pan is symmetric relative to plane C-C at any point between plane A-A and the internal end of the cover 5 at the front of the pan. Fig. 2a shows a toilet pan without the external cover 5. The toilet bowl 1 has a top edge 6, which forms the top part of the toilet bowl 1, and more precisely a fragment of the top internal surface of the toilet bowl 1 located directly below the external cover 5, with an approximately elliptical shape, which top edge 6 is normally covered by the external cover 5 and whose elliptical hole is slightly bigger than the hole in the external cover 5. The top edge 6 is made as a flat ring located in the top part of the pan, with walls essentially vertical, and is preferably 66 to 93 mm high. The flush water inlet hole 7 is preferably located in the rear area of the toilet bowl 1, in its top part, preferably at the highest possible point of the route of flush water. The inlet hole 7 is reached through an inlet pipe 8, which is preferably positioned in parallel to plane C-C and in perpendicular to the toilet pan's installation wall (not shown). Downstream of the inlet hole 7, there is a channel 9 that drains flush water to the toilet bowl 1 and is terminated with an outlet 10. The inlet hole 7 in the embodiment has a circular cross section and a diameter ranging from 15.5 to 16.5 cm², preferably 16.04 cm². The inlet hole 7 may also have a cross section of a different shape, but regardless of that shape, the cross sectional area of the inlet hole 7 may be 16 to 17.5 cm², preferably 16.81 cm². Such a relatively large cross section ensures the inflow of an adequate volume of water to the channel 9, so the kinetic energy of flush water can be well used.

[0040] In the channel 9, more or less at the halfway point of its curve, there is a compartment 14 made as a step or bulge running at the bottom of the channel 9, essentially across its length, from one of its walls (sides) to the other. The compartment 14 is easier to see in Fig. 2b, and its height in the embodiment is 4 mm to 10 mm, preferably 5 mm, and its width is 1 mm to 15 mm, preferably 4 mm. The said compartment 14 acts as a limiter that shuts off water inflow and separates flush water contained in the channel 9, so that it does not flow out of the channel 9 after flushing. The channel 9 is shaped in such a way that it is sloped slightly upwards from the inlet hole 7 to the compartment 14, whereas from the compartment 14 to the outlet 10 it is sloped slightly downwards. Such a shape of the channel 9 allows the inlet hole 7 to be located relatively high, which in turn enables reducing the non-flushed area inside the toilet bowl 1 and the time of outflow of water residues from the channel 9, as only a small amount of water contained between the chamber 14 and the outlet 10 flows out into the bowl 1.

[0041] In known toilet pans which do not have such a compartment 14, once the pan is flushed, a part of water that reached the channel from the inlet hole remains in the channel, which results from water surface tension and the channel shape, particularly its inclination. The remaining water thus keeps flowing down from the channel for a long time, forming a thin flux. In the toilet pan according to the invention, if residual water remains in the channel 9 after flushing, the compartment 14 will separate it so that a part of water will remain in the channel 9 or will flow back towards the inlet hole 7, and the residue, i.e. a small volume contained behind the compartment 14 from the outlet 10 side, will flow down to the toilet bowl 1. In consequence, flush water will very soon stop flowing out after flushing, which eliminates the issue of water leaking in the form of a thin flux. Additionally, such a water leak in known pans causes scale deposits in that area, and therefore, owing to the compartment 14, the pan becomes more hygienic and easier to clean.

[0042] In the embodiment, the channel 9 is approximately J-shaped, with its end more bent upwards, while its cross section, especially near the channel outlet 10, is flattened, i.e. its height is notably larger than its width. The channel 9 is formed in such a way that the first slightly arched (bent according to the line of the top edge 6) section of that channel 9 is directed to the right side of the toilet pan (essentially in parallel to planes A-A and B-B), further has a curve, i.e. a bend formed in such a way that the channel 9 turns by approximately 180°, and as a result the channel outlet 10 is located on the right side of the bowl 1 but is directed to the opposite side, in this case to the left. The outlet 10 of the channel 9 is preferably longitudinal in shape, extending in vertical direction. Preferably, the relation of between the height and the width of that outlet 10 is 4.0 to 4.12, and most preferably 4.06. More specifically, the height of the outlet 10 may be 68 to 74 mm, more preferably 71 mm, and its width may be 17 to 18 mm, more preferably 17.5 mm. The outlet 10 is designed in such a way that water flowing out of it is directed to the inner surface of the toilet bowl 1, specifically to the inner surface of its top edge 6, in the rear part of the toilet bowl 1, which is easier to see in Fig. 3. Fig. 3 shows a toilet pan according to the invention at a different angle than in Fig. 2a. Therefore, the supply of water to the toilet bowl 1 is asymmetric, and in this case water is supplied from the right side of the toilet bowl 1 (relative to plane C-C). Appropriate routing of water flux is supported by a protrusion 11 at the outlet 10 of the channel 9. The cross section of the channel 9 is flattened, i.e. its height is larger than its width. In the embodiment, the channel is rectangular, but its cross section may have any other shape as long as the channel appropriately serves its function. To properly use the kinetic energy of water flux, the channel 9 should not be bent too sharply, in particular it should not have any rectilinear geometric shapes. The radius of curvature of the arch of channel 9 is preferably 27 to 40 mm.

[0043] The toilet pan according to the invention, in the embodiment, has thresholds, upperthreshold 12 and lower threshold 13, which run around the toilet bowl 1 (inside it) and allow to maintain water flux inside the toilet bowl 1 so to allow more circles of water flux inside the toilet bowl 1.

[0044] Fig. 4a and Fig. 5 show the toilet pan in a cross section through plane A-A. In Fig. 4a, we can clearly see the shape of the inner surface of top edge 6 as well as the arrangement and shape of the outlet 10 of the channel 9. In addition, Fig. 4a and Fig. 5 clearly show the position and shape of the upper threshold 12 and lower threshold 13. The thresholds have the form of bulges; the upper threshold 12 is located at the level of the outlet 10 of the channel 9, whereas the lower threshold 13 is located below the halfway point between the upper threshold 12 and the level of water surface, starting from the upper threshold 12, preferably at 2/3 of that distance. With regard to the top edge 6 of the bowl 1, and using absolute values, the lower threshold 13 is located at least 17 cm, preferably 17.3 cm, from the top edge of the bowl, the distance being measured in straight line (vertically) from the verge of the top edge 6 of the bowl to the level where the lower threshold 13 is located. Due to the existence of two thresholds, between the level of water surface and the lower threshold 13, situated lower, the pan has an approximately cylindrical shape, more specifically the shape of a bevelled cone, which, as already mentioned, causes the formation of a high component speed directed down, and thus faster water drainage to the outlet 4.

[0045] Water flowing out of the outlet 10 has a kinetic energy that results from the amount of water that must be supplied to flush the toilet bowl 1 and from the height at which the tank supplying the toilet pan with water is situated. The kinetic energy of water is related to the speed at which water flows out from the outlet 10, according to relation E_k=(mv²)/2. The water flowing out is affected by two forces: gravity and the force related to a rotary motion in a circle. We may approximately calculate in theory that water will flow down quite fast to the trap 3 of the pan (approximately 40 cm) and will not manage to go around the entire toilet bowl 1 and thus to wash its entire inner surface. In order for the water to wash the entire bowl 1, we need the upper threshold 12 (and possibly the lower threshold 13), which will enable for at least one circle of water around the toilet bowl 1.

[0046] The above theoretic considerations are, however, insufficient to accurately determine the optimum position and shape of the upper threshold 12 in the toilet bowl 1. In order for the toilet pan to properly serve its function, it is required to keep appropriate dimensions of that upper threshold 12 (and possibly the lower threshold 13): they must fall within appropriate ranges. The dimensions of that upper threshold 12 are determined by the following factors: if the threshold is too small, water will flow down to the trap 3 too fast (the pan surface will not be washed); if the threshold is too big, the toilet bowl 1 will become unhygienic, as impurities will remain inside it. Accurate, appropriate dimensions of that upper threshold 12 have been determined by the author of this invention by way of experiments.

[0047] An example of appropriate dimensions of the upper threshold 12 are shown in Fig. 4b. In this embodiment, the distance between the beginning of the upper threshold 12 and the top end of the top edge 6, which is equal to the hight of the top edge 6, is 66 mm. The dimensions of the upper threshold 12 are as follows: the height of the upper threshold 12 measured vertically is 4 mm, and the width of the upper threshold measured horizontally is 9 mm, whereas the radius of curvature of the upper threshold 12 in normal plane relative to the inner surface of the toilet bowl 1 is 14 mm, and the radius of curvature of the arc between the top edge 6 and the beginning of the upper threshold 12 at the said plane is 20 mm. The lower threshold 13 has a radius of curvature in normal plane relative to the inner surface of the toilet bowl 1, ranging from 32 to 66 mm.

[0048] In addition, as mentioned above, i.e. to make it possible to maintain balance between adequately dynamic flushing (momentum) and adequately long water retention in the pan, translating into the accuracy of surface cleaning, the upper threshold 12 must be positioned in an appropriate location, i.e. at an appropriate height relative to the outlet 10 of the channel 9, preferably slightly above the bottom of the outlet 10. Preferably the upper threshold 12 is situated 2 to 5 mm above the outlet 10, most preferably 3.5 mm above the outlet 10.

[0049] Fig. 6 and Fig. 7 show the toilet pan in cross section through plane B-B. In this cross section, we can clearly see the shape of the bottom of the toilet bowl 1.

[0050] Fig. 8 and Fig. 9 show the toilet pan in cross section according to plane C-C. W can see here that the trap 3 is located in the bottom part of the toilet bowl 1 and connected to the rear outlet 4. In these Fig. 8 and Fig. 9, we can clearly see that the inner surface of the top edge 6 of the toilet bowl 1 is formed as a flat (non-curved) ring and crosses the upper threshold 12 to reach further part of the toilet bowl 1. The lower threshold 12 runs around the toilet bowl 1, but in the rear part of the toilet bowl 1 it is slightly gentler, i.e. less protruding. Such a structure allows for appropriate routing of water flux through a spiral inside the toilet bowl 1. In addition, also the protrusion 11 directs the water flux in an appropriate way. Further part of the toilet bowl 1, below the upper threshold 12, is curved, i.e. it has approximately the shape of a basin, and still has the lower threshold 13, which also protrudes a little less than in the rear part of the toilet bowl 1. Below the lower threshold 13, the toilet bowl 1 has a section whose shape is approximately cylindrical.

[0051] The existence of two thresholds according to the embodiment in Figs. 1-9 is the most preferable structure, as it causes the fastest flow of water down the bowl compared to asymmetric bowls and the bowl shown in Figs. 10-17.

[0052] In another embodiment, the toilet bowl 1 may have one threshold instead of two, which is shown in Fig. 10 to Fig. 17. All structural components of the toilet pan according to the invention are the same as in the described Fig. 1 to Fig. 9, except that the toilet pan from the embodiment shown in Figs. 10-17 does not have the lowerthreshold 13 but only a small bulge next to the hole leading to the trap 3, near the level of water surface.

[0053] A general view of the toilet pan with one threshold is presented in Fig. 10 (top view) and in Fig. 11 (oblique view). In this embodiment, the toilet bowl 1 has a threshold 12 situated below the top edge 6, but has no lower threshold 13. In consequence, below the lower threshold, the toilet bowl 1 has a relatively steep slope going towards the outlet hole 2 and water surface, without another threshold that would stop the water flux, as clearly shown in Fig. 12 or Fig. 13.

[0054] Fig. 14 and Fig. 15 show a toilet pan according to the invention having one threshold, in cross section in plane B-B, analogically to Fig. 6 and Fig. 7, whereas Fig. 16 and Fig. 17 show that pan in cross section in plane C-C (analogically to Fig. 8 and Fig. 9).

[0055] Of course, the above embodiments are not limiting. For instance, we can imagine that the channel 9 along with the channel outlet 10 will be pointed in opposite directions than in the drawing; in other words, that the design of the toilet pan will be a mirror reflection of the design shown in the drawing.

[0056] Rotating water flux in the toilet bowl 1 may continuously cover a relatively large area around the water surface. In the embodiment, water flux is routed from the outlet 10 of the channel 9 to the inside, so it falls first on the rear central area inside the toilet bowl 1 (as shown in the drawing), where particularly strong dirt patches may exist.

[0057] The toilet pan according to the invention operates preferably only in gravimetric manner, i.e. only with the use of gravity and the kinetic energy of water. This means that the use of an internal pump feeding the toilet pan is not necessary, and thus the toilet pan is relatively cheap to manufacture and more cost-effective in terms of operation.

[0058] The rotary motion of water flux, so the route of the flux, is determined by a tangential direction of inflow of flush water from the inlet hole 7 and by the internal shape of the toilet bowl 1, and the downward motion is induced by gravity. Due to the lateral (asymmetric) inlet of water flux into the bowl as well as the internal shape of the bowl, the water flux has a relatively high kinetic energy and flows into the trap 3 with a high momentum. Therefore, the flushing operation is effective both on the inner surface of the toilet bowl 1 and in the bottom area located deeper, directly above the trap 3.

[0059] The toilet pan according to the invention may use a static trap or dynamic trap, the static trap being more preferable. Dynamic trap should be understood as, for example, a solution wherein due to artificial narrowing or shut-off of outflow, for example with a flap valve, water in the bowl is artificially swelled so to enable a subsequent sudden outflow with the use of the trap effect. Therefore, a dynamic trap includes movable parts used to impact the route of outflow.

[0060] The toilet pan may be made with various method of supplying flush water under a specified pressure, for example without a flush (in a pressurised water duct) or, more preferably, it may have a system combined with a flush, as in this case the potential energy of flush water can be better used. This refers in particular to a concealed cistern installed in an installation wall behind the toilet pan.

[0061] As already mentioned, water in the toilet bowl 1 falls first on the rear section of the top edge 6 and then, with a swirling motion, it flows down the toilet bowl 1 into the outlet hole 2, on its way being retained in the bowl 1 by the upper threshold 12 or the upper threshold 12 and lowerthreshold 13. During such swirling downfall in a spiral, water makes at least one rotation inside the bowl, and then falls into the outlet hole 2 at the level of water surface.

Claims

1. A water-flushed toilet pan with a rimless toilet bowl (1), with the supply of flush water in the rear top part of the toilet bowl (1), which includes an inlet pipe (8) terminated with an inlet hole (7) and a channel (9) located behind it, terminated with an outlet (10), wherein the outlet hole (2) to the trap (3) is located in the bottom part of the toilet bowl (1), the toilet pan having the first central plane (A-A), which, when the toilet pan is assembled, is parallel to the installation wall and abstractly divides the toilet pan through the centre of the outlet hole (2) into the front and rear section, which rear section adjoins the installation wall, as well as a perpendicular second central plane (C-C), which abstractly divides the toilet pan through the centre of the outlet hole (2) into the right and left section, and wherein the toilet bowl (1) has a top edge (6) that is a fragment of the top inner surface of the toilet bowl (1), located directly below the external cover (5) and having an approximately elliptical shape, formed as a flat circle whose walls are essentially vertical, on which top edge (6) an external cover (5) is installed, and the outlet hole (2) is shifted within that ellipse towards the rear of the toilet pan, and wherein the outlet (10) of the channel (9) is positioned asymmetrically to the second central plane (C-C), on the right or left side of the toilet bowl (1), in its upper area, so that flush water flows into the toilet bowl (1) falling first on the rear section of the top edge (6), in a direction essentially horizontal and tangential with the inner surface of the toilet bowl (1), and then performs rotary motion inside the toilet bowl (1), characterised in that

the internal shape of the toilet bowl (1), excluding the location of the outlet (10), has a symmetric shape relative to the second central plane (C-C);

the toilet bowl (1) on its internal side, at the level of the outlet (10) and directly below the top edge (6), has an upper threshold (12) formed as a bulge running horizontally around the inner surface of the toilet bowl (1), whereas it protrudes slightly less in the rear area of the toilet bowl (1) than in other areas thereof.

2. The toilet pan according to claim 1, characterised in that the height of the upper threshold (12) measured vertically is 4 mm, and the width of the upper threshold measured horizontally is 9 mm, whereas the radius of curvature of the upper threshold (12) in normal plane relative to the inner surface of the toilet bowl (1) is 14 mm, and the radius of curvature of the arc between the top edge (6) and the beginning of the upper threshold (12) at the said plane is 20 mm.

3. The toilet pan according to claim 1 or 2, characterised in that the first section of the channel (9) downstream of the inlet hole (7) is directed to the right or left side of the bowl and is slightly bent according to the shape of the top edge (6), and further has a curve of approximately 180°, so the outlet (10) is located on the right or left side of the toilet bowl (1) but directed to the opposite side than the said first section of the channel (9), so to the left or right side, correspondingly.

4. The toilet pan according to claim 1 or 2 or 3, characterised in that below the upper threshold (12) but above the level of water surface existing in the pan's operating condition, the toilet bowl (1) has a lower threshold (13) formed as a bulge running around the inner surface of the toilet bowl (1), whereas it protrudes slightly less in the rear area of the toilet bowl (1) than in other areas thereof.

5. The toilet pan according to claim 4, characterised in that the lower threshold (13) has a radius of curvature in normal plane relative to the inner surface of the toilet bowl (1) ranging from 32 to 66 mm.

6. The toilet pan according to claim 4 or 5, characterised in that the lower threshold (13) is located below the halfway point between the upper threshold (12) and the level of water surface, preferably at 2/3 of the distance between the upper threshold (12) and the level of water surface.

7. The toilet pan according to claim 4 or 5 or 6, characterised in that below the lower threshold (13), the toilet bowl (1) has a section shaped as a bevelled cone whose diameter is gradually reduced towards the trap (3).

8. The toilet pan according to any of claims 4 to 7, characterised in that between the upper threshold (12) and the lower threshold (13), the toilet bowl (1) is curved and essentially has the shape of a basin.

9. The toilet pan according to any of the previous claims, characterised in that the bottom of the channel (9) is provided with a compartment (14) formed as a bulge or a step that runs transversely to the length of that channel (9), between its walls, preferably at the halfway point of the curve of the channel (9), and more preferably behind the halfway point of the curve of the channel (9) viewed from the inlet hole (7) to the outlet (10).

10. The toilet pan according to claim 9, characterised in that the height of the compartment (14) is 4 to 10 mm, preferably 5 mm, and the width of the compartment (14) is 1 to 15 mm, preferably 4 mm.

11. The toilet pan according to any of the previous claims, characterised in that the cross sectional area of flush water inlet hole (7) is 15.5 to 16.5 cm², preferably 16.04 cm².

12. The toilet pan according to any of the previous claims, characterised in that the cross sectional area of the channel (9) in the part between the inlet hole (7) and the curve is 16 to 17.5 cm², preferably 16.81 cm².

13. The toilet pan according to any of the previous claims, characterised in that the channel's (9) cross section is flattened, which means it is longer in vertical direction and narrows down more at the outlet (10).

14. The toilet pan according to claim 12 or 13, characterised in that the channel's (9) cross section is rectangular.

15. The toilet pan according to claim 13 or 14, characterised in that the relation of the height of the vertical outlet (10) to the width of that outlet (10) is 4.0 to 4.12, preferably 4.06.

16. The toilet pan according to claim 15, characterised in that the height of the outlet (10) is 68 to 74 mm, preferably 71 mm, and the width of the outlet (10) is 17 to 18 mm, preferably 17.5 mm.

17. The toilet pan according to any of the previous claims, characterised in that the channel (9) has a curve with a radius of curvature of 27 to 40 mm.

18. The toilet pan according to any of the previous claims, characterised in that the height of the top edge (6) is 66 to 93 mm.

19. The toilet pan according to any of the previous claims, characterised in that the distance between the first central plane (A-A) and the point of the toilet bowl (1) most protruding frontwards is 240 mm.

Drawing