FLEXIBLE HOSE

Abstract

 Inhibition of the elasticity or bendability of a tube-incorporated flexible hose at a location where a tube inserted in the flexible hose is adhered is suppressed. The tube-incorporated flexible hose includes a flexible hose main body formed by spirally winding and integrating a synthetic-resin flexible strip, and a flexible tube integrally joined to an inner surface of the flexible hose main body by an adhesive material. Of the inner surface of the flexible hose main body, an inner peripheral part positioned at the inner-most periphery portion of the hose has two spiral regions disposed alternately and spirally. The two spiral regions have surfaces with different adhesive properties with respect to the adhesive material. In one spiral region, the flexible hose main body and flexible tube are joined to each other. In the other spiral region, the flexible hose main body and flexible tube are substantially not joined to each other.

Description

TECHNICAL FIELD

[0001] The present invention relates to a flexible hose made of synthetic resin with excellent flexibility. In particular, the present invention relates to a flexible hose with a tube joined and integrated with the inside of the hose along the length direction of the hose.

BACKGROUND ART

[0002] A tube-incorporated flexible hose with a tube joined and integrated with the inside of the hose is used, for example, as a vacuum cleaner hose. In the vacuum cleaner, the tube disposed on the inside of the hose is used for purposes such as sending cleaning liquid or reflux air, or passing wires (lead wires) through the tube. If the tube is not fixed within the hose, the tube may move around inside the hose, thus wearing or damaging the hose. Thus, the tube is in many cases joined and integrated with the inner surface of the hose with an adhesive material and the like.

[0003] At the part where the tube is adhered and integrated with the inner surface of the hose, the elasticity and/or flexibility of the hose tends to readily deteriorate due to the influence of the adhesive material. Thus, there is an anticipation that the tube is joined and integrated with the hose without adversely affecting the flexibility of the hose as much as possible.

[0004] Patent Literature 1 discloses a tube-incorporated flexible hose in which a flexible tube is adhered and integrated within a bellows-like flexible hose. In this tube-incorporated flexible hose, grooves and protrusions are formed on an inner wall portion of the hose along the bellows shape as viewed from the hose inside. At the same time, the tube is adhered and integrated with the inner wall portion of the hose at the protrusions. Patent Literature 1 discloses that such flexible hose can prevent inhibition of the elasticity or bendability of the flexible hose where the tube is adhered.

CITATION LIST

PATENT LITERATURE

[0005] Patent Document 1: JP-A-2009-024750

SUMMARY OF INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] The inventors attempted to improve the flexibility of the tube-incorporated flexible hose by a technology different from the technology disclosed in Patent Literature 1. Namely, an object of the present invention is to suppress the inhibition of the elasticity or bendability of a tube-incorporated flexible hose at the location where the tube inserted in the hose is adhered.

SOLUTIONS TO THE PROBLEMS

[0007]  As a result of detailed analysis, the inventors learned that the problem can be solved as follows, and completed the present invention. Namely, on an inner surface of a hose to which a tube can be joined by an adhesive material, two spiral regions are disposed alternately and spirally. The two spiral regions have surfaces with different adhesive properties with respect to the adhesive material. In one region, the tube is joined; in the other region, the tube is substantially not joined. Thus, the tube and the hose can be intermittently joined.

[0008] A flexible hose of the present invention includes: a flexible hose main body including a hose wall formed by spirally winding and integrating a flexible strip of a synthetic resin; and a flexible tube joined and integrated with an inner surface of the flexible hose main body along a length direction of the hose by an adhesive material, wherein: of the inner surface of the flexible hose main body, an inner peripheral part that is positioned at an inner-most periphery portion of the hose includes two alternately spirally disposed spiral regions; the two spiral regions respectively include surfaces with different adhesive properties with respect to the adhesive material; the flexible hose main body inner peripheral part and the flexible tube are joined to each other in one of the spiral regions; and the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other in the other of the spiral regions (first invention).

[0009] In the flexible hose of the present invention, the adhesive material is preferably a thermoplastic adhesive material; and the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other preferably has a melting point lower than a melting point of the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other (second invention).

[0010] In addition, the flexible hose of the present invention, the adhesive material is preferably a thermoplastic adhesive material; the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other is preferably a thermoplastic resin compatible with the thermoplastic adhesive material; and the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other is preferably a thermoplastic resin incompatible with the thermoplastic adhesive material (third invention).

[0011] Moreover, in the flexible hose of the present invention, the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other is preferably surface-treated for enhancing adhesive property with the adhesive material (fourth invention).

[0012] Furthermore, in the flexible hose of the present invention, the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other is preferably surface-treated to render the spiral region non-adhesive with respect to the adhesive material (fifth invention).

EFFECTS OF THE INVENTION

[0013] According to the flexible hose (first invention) of the present invention, in a tube-incorporated flexible hose, inhibition of the elasticity or bendability of the flexible hose at the location where the tube inserted in the hose is adhered can be suppressed.

[0014] Further, by adopting the configuration of second through fifth inventions, the effect that the tube-incorporated flexible hose can be manufactured efficiently can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 

FIG. 1 is an exterior view of a vacuum cleaner including a tube-incorporated flexible hose according to the present invention.

FIG. 2 is a partially cross-sectional view illustrating a structure of the tube-incorporated flexible hose according to a first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the tube-incorporated flexible hose according to the first embodiment of the present invention, showing, in enlargement, a part where a hose main body and a tube are joined.

FIG. 4 is a cross-sectional view showing, in enlargement, a hose wall part of the hose main body of the tube-incorporated flexible hose according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view of a flexible strip used for manufacturing the hose main body of the tube-incorporated flexible hose according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view of the tube-incorporated flexible hose according to a second embodiment of the present invention, showing in enlargement a part where the hose main body and the tube are joined.

FIG. 7 is a cross-sectional view of the tube-incorporated flexible hose according to a third embodiment of the present invention, showing in enlargement a part where the hose main body and the tube are joined.

FIG. 8 is a cross-sectional view of the tube-incorporated flexible hose according to a fourth embodiment of the present invention, showing in enlargement a part where the hose main body and the tube are joined.

DESCRIPTION OF EMBODIMENTS

[0016] In the following, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the individual embodiments below. The present invention may be implemented by modifying the configuration or uses of the embodiments. According to a first embodiment, a tube-incorporated flexible hose 1 embodied in a household vacuum cleaner will be described. FIG. 1 is an exterior view of the vacuum cleaner as a whole. The tube-incorporated flexible hose 1 is connected at one end thereof to an intake opening of a cleaner main body 99 via a connecting tube (connecting member) 95. The other end of the tube-incorporated flexible hose 1 is connected to a hand operating portion 98. Continuously with the hand operating portion 98, there are connected an extension pipe 97 and then a floor nozzle 96. Such is the configuration of the vacuum cleaner.

[0017] The tube-incorporated flexible hose 1 is provided with a plurality of conductive wires. The conductive wires are inserted through the tube of the tube-incorporated flexible hose 1. The conductive wires enable transmission of an input signal from a switch on the hand operating portion 98 to the cleaner main body 99, and supply of electric power to a brush driving motor built inside the floor nozzle 96. In the vacuum cleaner, the tube built inside the tube-incorporated flexible hose 1 may be used for sending a liquid, such as cleaning liquid, or reflux air.

[0018] FIGS. 2 and 3 illustrate the structure of the tube-incorporated flexible hose 1 according to the first embodiment of the present invention. In FIG. 2, an upper-left half of the hose is shown in a cross-sectional view, with the remainder shown in an exterior view. FIG. 3 is a cross-sectional view showing in enlargement a part where a hose wall and the tube are joined. In these figures, the tube 3 is shown in exterior view rather than cross section. Illustration of the conductive wires inserted through the tube 3 in the drawings is omitted.

[0019] In the tube-incorporated flexible hose 1, a flexible hose main body 2 including a hose wall formed of a flexible synthetic resin in a substantially cylindrical shape, and the flexible tube 3 are joined and integrated with each other by an adhesive material 4. The tube 3 is disposed on an inner surface of the flexible hose main body 2 along the length direction of the hose, and is adhered and integrated therewith.

[0020] FIG. 4 shows the structure of the flexible hose main body 2 in a cross section of a hose wall part. In the flexible hose main body 2, a hose wall 21 includes a spiral winding of a synthetic-resin flexible strip T, with adjacent side edge portions of the flexible strip T being integrated with each other. According to the present embodiment, the flexible strip T includes, as shown in cross section in FIG. 5, a part 21T with a substantially S-shaped cross section and forming the hose wall 21, and a part 22T forming a lip 22.

[0021] Thus, according to the present embodiment, the flexible hose main body 2 is a hose integrating the hose wall 21 and the lip 22. The hose wall 21 includes spiral grooves and protrusions on an inner surface thereof. Namely, the inner surface of the hose wall 21 is provided with grooves and protrusions disposed spirally, forming grooves or protrusions as viewed from the inside of the hose. The hose wall 21 is formed in a bellows shape by the S-shaped cross sectional part 21T of the flexible strip T. The grooved parts on the inner surface of the hose directly correspond to the protruding parts on the outer surface of the hose.

[0022] On the inner surface of the hose wall 21, the lip 22 is disposed spirally along the grooves in such a manner as to cover the grooves on the inner surface. In the flexible hose main body 2, the lip 22 and an inner peripheral portion 204 of the hose wall 21 are positioned on the inner-most periphery portion of the hose. To the inside of the hose, only the lip 22 and the inner peripheral portion 204 of the hose wall are exposed. Namely, in the flexible hose main body 2, the inner peripheral part of the hose main body that is positioned on the hose inner-most periphery portion includes the two spiral parts, i.e., the lip 22 and the inner peripheral portion 204. In other words, of the inner surface of the flexible hose main body, the inner peripheral part positioned at the inner-most periphery portion of the hose includes two spiral regions S1 and S2 that are alternately spirally disposed. According to the present embodiment, the lip 22 corresponds to the first spiral region S1, and the inner peripheral portion 204 corresponds to the second spiral region S2.

[0023] When the tube 3 is joined and integrated with the inner surface of the flexible hose main body 2 by the adhesive material 4, the tube 3 is disposed to face both the lip 22 and inner peripheral portion 204. Then, a gap between the hose main body 2 and the tube 3 is adhered by the adhesive material 4. As the adhesive material 4, an adhesive material with good adhesive property with respect to the tube 3 is selected.

[0024] The lip 22 of the hose main body 2 and the inner peripheral portion 204 of the hose wall are formed of different resin materials. The resin material included in the lip 22 and the resin material included in the inner peripheral portion 204 have different adhesive properties with respect to the adhesive material 4. In other words, the adhesive properties of surfaces of the two spiral regions S1 and S2 disposed at the inner-most periphery of the hose main body are different from each other with respect to the adhesive material 4.

[0025] According to the present embodiment, the resin included in the lip 22 (first spiral region S1) is a resin with high adhesive property with respect to the adhesive material 4. The resin included in the inner peripheral portion 204 (second spiral region S2) of the hose wall has low adhesive property (substantially non-adhesive) with respect to the adhesive material 4. As a result, at the lip 22 (first spiral region S1) of the tube-incorporated flexible hose 1, the tube 3 and the flexible hose main body 2 are adhered (joined) and integrated by the adhesive material 4. On the other hand, at the inner peripheral portion 204 (second spiral region S2) of the hose wall, the tube 3 and the flexible hose main body 2 are substantially not adhered (joined) nor integrated.

[0026] That in the second spiral region S2 the hose main body 2 and the tube 3 (adhesive material 4) are substantially not adhered nor integrated with each other (substantially non-adhered) is not limited to the both being totally not adhered to each other. That the both being substantially not adhered includes a weak adhered state such that the adhesion between the hose main body 2 and the tube 3 (adhesive material 4) in the second spiral region S2 is eroded (destructed) by displacement or force applied during use of the tube-incorporated flexible hose 1.

[0027] An example of the synthetic resin included in the flexible hose main body 2 or the tube 3 is a relatively soft synthetic resin material, such as a polyolefin-based resin. Examples of the polyolefin-based resin include polypropylene resin (PP), polyethylene resin (PE), and ethylene-vinyl acetate copolymer resin (EVA). Soft vinyl chloride resin (PVC resin) or thermoplastic elastomer (TPE) may also be used. The flexible hose main body 2 or the tube 3 may include other resin materials.

[0028] As the adhesive material 4, a hot-melt type adhesive material of the same type of resin as the flexible hose main body 2 or tube 3 may be used. Other adhesive materials, such as adhesives using solvent and reactive adhesives, may be used as the adhesive material 4. The tube 3 may include a thermoplastic resin. Thus the tube 3 can be adhered to the hose main body 2 by melting a part of a surface of the tube 3 and using the part as the adhesive material 4.

[0029] According to the present embodiment, the hose wall part 21 (the S-shaped part 21T of the strip T) of the flexible hose main body 2 includes an olefin resin with melting point of 110°C, specifically linear low density polyethylene (LLDPE) resin. The hose wall inner peripheral portion 204 located at the hose inner-most periphery (the second spiral region S2) also includes the same resin. On the other hand, the lip 22 (the lip part 22T of the strip T, and the second spiral region S2) of the flexible hose main body 2 includes an olefin resin with melting point of 90°C, specifically an EVA resin with high vinyl content. As the adhesive material 4, a thermoplastic adhesive material (EVA resin) is used.

[0030] By selecting such materials, the following can be realized. By joining and integrating the hose wall part 21 and the lip 22 by coextrusion, the flexible resin strip T can be formed. Further, by appropriately adjusting the melting temperature or adhesion condition of the adhesive material 4, particularly by taking advantage of a melting point difference, the lip 22 and the adhesive material 4 can be adhered to each other while the hose wall inner peripheral portion 204 and the adhesive material 4 are substantially not adhered to each other.

[0031] As a means by which one of the two spiral regions S1 and S2 is caused to adhere to the adhesive material 4 and the other is caused to substantially not adhere to the adhesive material 4, the surface adhesive property may be varied between the spiral regions S1 and S2. In order to vary the adhesive property, the difference in melting point may be utilized, as according to the present embodiment, or the degree of resin compatibility may be varied as according to an embodiment described below. Alternatively, one or both of the two regions may be subjected to surface treatment for increasing or decreasing adhesive property (i.e., make substantially non-adhesive), thus making the surface adhesive property different between the spiral regions S and S2.

[0032] A method of manufacturing the tube-incorporated flexible hose 1 will be described. The tube 3 is manufactured by a well-known method, such as extrusion molding, or a so-called continuous blow molding process.

[0033] When the flexible hose main body 2 is manufactured, first, two types of resin material are supplied to an extruder, and the resin materials are coextruded in a semi-molten state. Thus, the flexible strip T shown in FIG. 5 is fabricated. The strip T includes the substantially S-shaped part 21T, and the lip part (extension part) 22T. The substantially S-shaped part 21T includes an inward side edge portion 201, an outer peripheral portion 202, a rise portion 203, the inner peripheral portion 204, and an outward side edge portion 205 which are successively continuously disposed. The lip part (extension part) 22T is branched from a part where the inner peripheral portion 204 and the outward side edge portion 205 are connected. The substantially S-shaped part 21T is formed of LLDPE resin, and the lip part 22T is formed of EVA resin, both of which are formed by coextrusion. The extruded strip T is thereafter cooled so as to solidify its cross-sectional shape.

[0034] Thereafter, the flexible hose main body 2 is manufactured from the flexible strip T by a so-called spiral molding method. The flexible strip T is spirally wound around a guide shaft of a well-known hose manufacturing apparatus. The strip T is wound in such a manner that the inward side edge portion 201 overlaps the outward side edge portion 205 of the strip that has previously been wound. Between the inward side edge portion 201 and the outward side edge portion 205 overlapping each other, an adhesive 30 is filled so as to adhere the portions, thereby joining and integrating the portions with each other. In this way, the substantially S-shaped part 21T is made into the hose wall 21 with the spiral grooves and protrusions, and the lip part 22T into the lip 22, while the flexible hose main body 2 is continuously manufactured. As the adhesive 30, a hot-melt type adhesive material of the same type of resin as the substantially S-shaped part 21T of the strip T may be used.

[0035] The resultant flexible hose main body 2 is cut to a predetermined length, and the tube 3 is inserted into the hose main body along the length direction of the hose. Then, the adhesive material 4 is used to join and integrate the tube 3 with the inner surface of the hose main body 2, whereby the tube-incorporated flexible hose 1 is obtained. Such adhering steps may be performed according to well-known adhering steps disclosed in EP1011960 (B1), or WO2008/035484, for example.

[0036] By appropriately adjusting the selection of the adhesive material, the adhesive condition, and the like in the adhering steps, the tube-incorporated flexible hose 1 according to the foregoing embodiment can be obtained. In the tube-incorporated flexible hose 1, in one spiral region S1, the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are joined (adhered) to each other, while in the other spiral region S2, the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are substantially not joined.

[0037] The operation and effect of the tube-incorporated flexible hose 1 will be described. In the tube-incorporated flexible hose 1, the inner-most periphery part of the hose main body 2 at which the tube 3 and the hose main body 2 are disposed opposite each other so as to be adhered to each other includes the two spiral regions S1 and S2 with different adhesive properties of the adhesive material 4. In one spiral region S1, the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are joined to each other. In the other spiral region S2, the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are substantially not joined. Thus, the hose main body 2 and the tube 3 are adhered to each other intermittently along the longitudinal direction of the tube.

[0038] If the hose main body 2 and the tube 3 are continuously adhered to each other, the adhered part of the hose wall is hardened by the influence of the adhesive material 4 or the tube 3, thus inhibiting ready deformation. As a result, the deformation of the hose main body is greatly restricted, and the flexibility or elasticity of the tube-incorporated flexible hose is inhibited. On the other hand, in the tube-incorporated flexible hose 1, the hose main body 2 and the tube 3 are intermittently adhered along the longitudinal direction of the tube. Thus, the hose wall 21 is permitted to be deformed at portions where the tube is substantially not adhered, so that the elasticity of the hose is not interfered with. Accordingly, in the tube-incorporated flexible hose 1, inhibition of the elasticity or bendability of the flexible hose 1 at the location where the tube 3 inserted in the hose is adhered can be suppressed.

[0039] Particularly, in the tube-incorporated flexible hose 1 according to the present embodiment, the adhesive material 4 is a thermoplastic adhesive material represented by a hot-melt adhesive material. Further, the melting point of the synthetic resin forming the spiral region S1 in which the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are joined to each other is lower than the melting point of the synthetic resin forming the spiral region S2 in which the inner peripheral part of the flexible hose main body 2 and the flexible tube 3 are substantially not joined to each other. In this way, adhesion or non-adhesion between the hose main body 2 and the tube 3 can be readily controlled, thus allowing efficient manufacture of the tube-incorporated flexible hose 1.

[0040] According to the present embodiment, the difference in melting point of the resin of the two spiral regions is 20°C. Preferably, the melting point difference is 10 to 50°C and particularly preferably on the order of 15 to 30°C.

[0041] Preferably, as in the tube-incorporated flexible hose 1 according to the present embodiment, the hose main body 2 is fitted with the lip 22 branching from the bellows-like hose wall 21, and the spiral region S1 in which the hose main body 2 and the tube 3 are adhered each other is formed at the lip 22. In this way, the hose main body 2 and the tube 3 are adhered each other only at the lip part 22 branching from the hose wall 21. The bellows-like hose wall part 21 has no part that is adhered to the adhesive material 4. Thus, deformation or expansion/contraction of the hose wall part 21 is not inhibited. Inhibition of the elasticity or bendability of the tube-incorporated flexible hose 1 can be particularly effectively suppressed.

[0042] The present invention is not limited to the above embodiment, and may be implemented with various modifications. In the following, other embodiments of the present invention will be described. The following description will focus on different parts from the above embodiment, while omitting detailed description of similar parts. The following embodiments may be implemented with some parts thereof combined or substituted.

[0043] FIG. 6 illustrates a tube-incorporated flexible hose 5 according to a second embodiment of the present invention. According to the present embodiment, the tube 3 is adhered to the flexible hose main body 55 by the adhesive material 4. The flexible hose main body 55 has a cross-sectional shape similar to that of the first embodiment. In the present embodiment, a coating portion 53 is disposed in contact with the hose inside at an inner peripheral portion 504 of the bellows-like hose wall 51.

[0044] Further, according to the present embodiment, the S-shaped cross sectional part of the hose wall 51 and the lip portion 52 include the same resin material. Meanwhile, the coating portion 53 includes a different resin material from the hose wall 51 and lip 52. Specifically, the hose wall 51 and the lip 52 include a resin material which is incompatible (i.e., hard to be thermally welded) with the thermoplastic adhesive material 4. The coating portion 53 includes a resin material which is compatible (i.e., readily thermally welded) with the thermoplastic adhesive material 4.

[0045] Namely, according to the present embodiment, the part of the coating portion 53 disposed at the inner peripheral portion 504 of the hose wall 51 corresponds to a first spiral region S4 that is adhered to the adhesive material 4 (tube 3). The part of the lip 52 corresponds to a second spiral region S3 that is substantially not adhered to the adhesive material 4 (tube 3).

[0046] More specifically, according to the present embodiment, as the adhesive material 4, a hot-melt adhesive material mainly of EVA resin is used. The hose wall 51 and the lip 52 include a soft vinyl chloride resin (soft PVC resin) which is incompatible with the EVA resin. The coating portion 53 includes EVA resin. The inner peripheral portion 504 of the hose wall 51 and the coating portion 53 are integrated via an adhesive layer (not shown) of a modified EVA resin, for example.

[0047] Alternatively, in the tube-incorporated flexible hose 5 according to the present embodiment, as the adhesive material 4, a hot-melt adhesive material of mainly a low density polyethylene (LDPE) resin may be used. Further, the hose wall 51 and the lip 52 may include a soft vinyl chloride resin (soft PVC resin) incompatible with LDPE resin, and the coating portion 53 may include LDPE resin. In this case, the inner peripheral portion 504 of the hose wall 51 and the coating portion 53 may be integrated by an adhesive layer of polyethylene resin grafted with vinyl chloride, for example.

[0048] The tube-incorporated flexible hose 5 according to the present embodiment can also be manufactured by steps similar to those according to the first embodiment. In the tube-incorporated flexible hose 5 according to the present embodiment, inhibition of the elasticity or bendability of the tube-incorporated flexible hose 5 can also be suppressed.

[0049] When the two spiral regions are disposed alternately in the inner peripheral part at the inner-most periphery of the hose at which the hose and the tube are disposed opposite each other so as to be adhered, it is a discretionary matter which of the spiral regions should be able to adhere to the adhesive material and which of the spiral regions should be substantially not adhere to the adhesive material.

[0050] The difference in adhesive property between the first spiral region and the second spiral region may be provided by utilizing a difference in compatibility with the synthetic resin of the thermoplastic adhesive material, as according to the present embodiment. In this way, adhesion or non-adhesion between the hose main body 55 and the tube 3 can be easily controlled. Thus, the tube-incorporated flexible hose 5 can be efficiently manufactured.

[0051] FIG. 7 illustrates a tube-incorporated flexible hose 6 according to a third embodiment of the present invention. The present embodiment is similar to the first embodiment in that the tube 3 is adhered to a flexible hose main body 66 by the adhesive material 4. The present embodiment differs from the first embodiment and the second embodiment in the configuration of the flexible hose main body 66. In the flexible hose main body 66, a spiral reinforcing member 61 of the hose main body includes a spirally wound resin-coated metal wire which is a hard steel wire coated with hard resin. Further, the flexible hose main body 66 includes a hose wall 62 overlapping the spiral reinforcing members 61 and 61, which are adhered and integrated with each other. The hose wall 62 is formed by spirally winding a strip of soft resin and integrating the strips.

[0052] The flexible hose main body 66 is enabled to expand and contract through extension and warping of the soft resin hose wall 62 disposed between the spiral reinforcing members 61 and 61. According to the present embodiment, the hose wall 62 of the flexible hose main body 66 is disposed at the inner-most periphery part of the hose between the spiral reinforcing members 61 and 61. The adhesive material 4 by which the tube 3 is joined and integrated is adhered to this part.

[0053] The part between the spiral reinforcing members 61 and 61 of the hose wall 62 is divided into three spiral regions S5, S6, and S5 disposed in parallel with the spiral reinforcing member 61. In these spiral regions, the first spiral region S5 (parts in sections A in the hose wall cross section) that is adhered to the adhesive material 4, and the second spiral region S6 (parts in sections B in the hose wall cross section) that is substantially not adhered to the adhesive material 4 are alternately disposed. As viewed from the hose inside, these are disposed side by side, such as: the spiral reinforcing member 61, the first spiral region S5, the second spiral region S6, the first spiral region S5, the spiral reinforcing member 61, and so on. Thus, three or more spiral regions may be provided at the inner-most periphery of the hose.

[0054] According to the present embodiment, the hose wall 62 is formed of the soft resin flexible strip including homogeneous material. Meanwhile, the second spiral region S6 is coated with a substance that interferes with its adhesive property with the adhesive material 4. Namely, this region is surface-treated so as to be non-adhesive with respect to the adhesive material. Thus, the adhesive material 4 and the hose wall 62 do not adhere to each other. Accordingly, in the present embodiment, inhibition of the elasticity or bendability of the tube-incorporated flexible hose 6 can also be suppressed.

[0055] Specifically, the hose wall 62 is formed of EVA resin, and the adhesive material 4 is also formed mainly of EVA resin. In the first spiral region S5 that is not subjected to coating process, the hose wall 62 and the adhesive material 4 are adhered to each other. On the other hand, the part of the second spiral region S6 is coated with a treatment agent (non-adhesive coating agent) that does not adhere to the adhesive material 4 of mainly EVA resin, examples of the treatment agent being a fluorine-based release agent and a silicone-based oil repellant agent.

[0056] As in the present embodiment, when the adhesive property between the adhesive material 4 and the hose wall is adjusted by the application of the coating material having non-adhesive property, adhesion or non-adhesion between the hose main body 66 and the tube 3 can be easily controlled. Thus, the tube-incorporated flexible hose 6 can be efficiently manufactured.

[0057] FIG. 8 illustrates a tube-incorporated flexible hose 7 according to a fourth embodiment of the present invention. The present embodiment is similar to the other embodiments in that the tube 3 is adhered to a flexible hose main body 77 by the adhesive material 4. The present embodiment differs from the other embodiments in the structure of the flexible hose main body 77. In the flexible hose main body 77, a bellows-like hose wall 72 includes a spirally wound strip of synthetic resin extrusion-molded with grooves and protrusions, with adjacent side edge portions of the strip adhered and integrated with each other. The bellows-like hose wall 72 includes two streams of spiral grooves and protrusions.

[0058] The flexible hose main body 77 is enabled to expand or contract by deformation and expansion/contraction of the bellows-like hose wall 72. According to the present embodiment, in the bellows-like hose wall 72, two streams of spiral regions S7 and S8 are disposed at the inner-most periphery part of the hose, the spiral regions being formed as protrusions when viewed from the hose inside. The adhesive material 4 by which the tube 3 is joined and integrated is adhered to this part.

[0059] According to the present embodiment, the hose wall 72 is formed of the synthetic-resin flexible strip including homogeneous material. However, the first spiral region S7 is coated with a substance that enhances its adhesive property with the adhesive material 4. Namely, a surface treatment for enhancing adhesive property with the adhesive material 4 is performed. Specifically, the hose wall 62 is formed of a PP resin, and the adhesive material 4 is formed mainly of LDPE resin. In the second spiral region S8 that is not subjected to the coating process, the hose wall 62 and the adhesive material 4 do not substantially adhere to each other.

[0060] On the other hand, the part of the first spiral region S7 is coated with a primer that enables adhesion with the adhesive material 4. In this part, the adhesive material 4 and the hose wall 72 are adhered each other. Thus, according to the present embodiment, inhibition of the elasticity or bendability of the tube-incorporated flexible hose 6 can also be suppressed.

[0061] As indicated by the present embodiment, the spiral region S7 that adheres to the adhesive material 4 and the region S8 that does not substantially adhere to the adhesive material 4 do not have to be disposed directly adjacent to each other.

[0062] As according to the present embodiment, when the surface treatment for enhancing the adhesive property between the adhesive material 4 and the hose wall is performed by applying the primer and the like, adhesion or non-adhesion between the hose main body 77 and the tube 3 can be easily controlled. Thus, the tube-incorporated flexible hose 7 can be efficiently manufactured. The surface treatment for enhancing the adhesive property is not limited to the primer, and may involve other processes, such as the application of a coupling agent or plasma treatment and other treatments. The adhesive property of the two spiral regions may also be adjusted by using the primer according to the present embodiment and the non-adhesive coating material according to the third embodiment in combination.

[0063] The combination of the resin and the treatment agent and the like for causing the adhesive material 4 and the hose main body 2, 55, 66, or 77 to adhere or substantially not adhere to each other is not limited to the combination described in the foregoing embodiments by way of example. The resin, the treatment agent, or the adhesion condition may be selected or adjusted such that, based on well-known expertise, the adhesive material and the hose main body can adhere or substantially not adhere to each other.

[0064] The concrete shape or structure of the flexible hose main body is also not limited to the foregoing embodiments. Various hoses may be used as the flexible hose main body. Among others, when a flexible hose having a hose wall formed by spirally winding and integrating a synthetic-resin flexible strip is adopted, the two spiral regions that are alternately spirally disposed and that have different adhesive properties can be easily provided at the time of manufacture of the hose main body. Thus, manufacturing efficiency can be increased.

[0065] Further, the tube 3 may be of a linear tubular shape obtained by extrusion molding as described with reference to the foregoing embodiments by way of example, or it may be of other configurations. For example, the tube 3 may have a bellows-like tube wall obtained by continuous blow molding. Such tube is flexible and does not interfere with the hose flexibility, and is particularly preferable. The cross section of the tube may be circular or other shapes, such as elliptic, semicircular, or polygonal.

[0066] According to the foregoing embodiments, the tube-incorporated flexible hose for vacuum cleaners has been described by way of example. However, the tube-incorporated flexible hose according to the present invention may be applied to fields of technology other than vacuum cleaners, such as industrial hoses for sending a primary liquid and an auxiliary liquid. Namely, the uses of the tube-incorporated flexible hose are not particularly limited.

INDUSTRIAL APPLICABILITY

[0067] The flexible hose according to the present invention includes the tube integrated on the inner surface of the hose. The flexible hose according to the present invention permits insertion of a conductive wire or a flow of another fluid within the tube, thus providing high industrial utility value.

DESCRIPTION OF REFERENCE SIGNS

[0068] 

1

Tube-incorporated flexible hose

2

Flexible hose main body

21

Hose wall

204

Inner peripheral portion

22

Lip

S1

First spiral region

S2

Second spiral region

T

Flexible strip

21T

S-shaped part

22T

Lip part

3

Tube

4

Adhesive material

5, 6, 7

Tube-incorporated flexible hose

55, 66, 77

Flexible hose main body

51, 62, 72

Hose wall

52

Lip

61

Spiral reinforcing member

S4, S5, S7

First spiral region

S3, S6, S8

Second spiral region

99

Cleaner main body

98

Hand operating portion

97

Extension pipe

96

Floor nozzle

95

Connecting tube

Claims

1. A flexible hose comprising:

a flexible hose main body including a hose wall formed by spirally winding and integrating a flexible strip of a synthetic resin; and

a flexible tube joined and integrated with an inner surface of the flexible hose main body along a length direction of the hose by an adhesive material,

wherein:

of the inner surface of the flexible hose main body, an inner peripheral part that is positioned at an inner-most periphery portion of the hose includes two alternately spirally disposed spiral regions;

the two spiral regions respectively include surfaces with different adhesive properties with respect to the adhesive material;

the flexible hose main body inner peripheral part and the flexible tube are joined to each other in one of the spiral regions; and

the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other in the other of the spiral regions.

2. The flexible hose according to claim 1, wherein:

the adhesive material is a thermoplastic adhesive material; and

the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other has a melting point lower than a melting point of the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other.

3. The flexible hose according to claim 1, wherein:

the adhesive material is a thermoplastic adhesive material;

the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other is a thermoplastic resin compatible with the thermoplastic adhesive material; and

the synthetic resin forming the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other is a thermoplastic resin incompatible with the thermoplastic adhesive material.

4. The flexible hose according to claim 1, wherein the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are joined to each other is surface-treated for enhancing adhesive property with the adhesive material.

5. The flexible hose according to claim 1, wherein the spiral region in which the flexible hose main body inner peripheral part and the flexible tube are substantially not joined to each other is surface-treated to render the spiral region non-adhesive with respect to the adhesive material.

Drawing