JP2014066275A - Hose connection structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hose connection structure which prevents a flow passage from being blocked owing to freezing of rainwater at a connection place between a hose and a connection joint.SOLUTION: A hose connection structure includes a hose 30 formed of thermoplastic elastomer and a connection joint 10 which is molded out of a resin material, which can be thermally deposited on the hose 30, by injection integrally with the hose 30 while using the hose 30 as an insert member. The connection joint 10 has an upstream-side hose connection part 13 to which an end of the hose is connected, and the hose connection part 13 is formed in a condition of d1≤d2, where d1 is the inner diameter of a flow passage of the hose 30 and d2 is the inner diameter of a flow passage of the hose connection part 13. An inner wall surface forming the flow passage of the hose connection part 13 is connected to an inner wall surface forming the flow passage of the hose in level or by a continuous curved surface.

Description

  The present invention relates to a hose connection structure having a connection joint to which a hose is connected.

  Conventionally, as a piping system using this type of hose connection structure, a mechanism for discharging rainwater or the like from a groove arranged around a sunroof of an automobile to the lower part of the automobile through a hose is known. In the piping system, connection joints are used to branch-connect a plurality of hoses (Patent Documents 1 and 2). In the connection joint, each hose is connected by press-fitting the end of the tubular joint body into each hose.

JP 2009-115153 A JP 2005-48857 A

  In the hose connection structure according to the prior art, in a use state where a small amount of water flows inside the hose at a low temperature, the connection portion between the inner wall forming the flow path of the hose and the inner wall forming the flow path of the connection joint Ice may adhere. The ice adhering to these connection locations may cause problems such as narrowing the channel or closing the channel.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

(1) According to one aspect of the present invention, a hose connection structure is provided. The hose connection structure includes a hose formed from a thermoplastic elastomer, and a connection joint integrally formed with the hose by injection molding a resin material that can be thermally welded to the hose using the hose as an insert member. The connection joint has a hose connection part for connecting the end of the hose, and the hose connection part has an inner diameter of the flow path of the hose d1 and an inner diameter of the flow path of the hose connection part d2. Then, it is formed by d1 ≦ d2, and the inner wall surface that forms the flow path of the hose connection portion is connected to the inner wall surface that forms the flow path of the hose with a curved surface that is flush with or continuous with the inner wall surface. Can take.
In the hose connection structure of the above aspect, when the inner diameter of the flow path of the hose is d1 and the inner diameter of the flow path of the hose connection section is d2, the hose connection section is formed by d1 ≦ d2, and the hose connection section The inner wall surface that forms the flow path is connected to the inner wall surface that forms the flow path of the hose with a flat or continuous curved surface, that is, there is no step at the connection portion of the flow path between the hose and the hose connection portion. Therefore, water flows smoothly from the upstream flow path of the hose to the flow path of the connection joint, and does not stagnate as water droplets at the connection location. Therefore, even if the temperature in the vicinity of the hose connection structure is below freezing point, problems such as blockage of the flow path due to freezing do not occur at the connection point.
Moreover, since the hose is formed from a thermoplastic elastomer and the connection joint is formed from a resin material that is heat-welded to the thermoplastic elastomer, both members are heat-welded by injection molding and have high bonding strength.

(2) In the hose connection structure of the above aspect, the thermoplastic elastomer may be an olefin-based elastomer, and the resin material of the connection joint may be an olefin-based resin.

(3) In the hose connection structure according to the above aspect, the hose includes a flare whose diameter is increased at an end of the hose, and the hose connection portion holds the inner peripheral side and the outer peripheral side of the flare. It can take the structure provided with. With this configuration, the hose clamping portion of the hose connection portion clamps the flare of the hose from the inner peripheral side and the outer peripheral side, so that the hose can be connected with a large mechanical joint strength.

It is sectional drawing which shows the hose connection structure concerning one Example of this invention. It is sectional drawing to which the vicinity of the hose connection part of FIG. 1 was expanded. It is explanatory drawing explaining the manufacturing process of a hose connection structure. It is sectional drawing which shows the hose connection structure concerning another Example.

(1) Configuration of Hose Connection Structure FIG. 1 is a cross-sectional view showing a hose connection structure according to an embodiment of the present invention. The hose connection structure is applied to, for example, a piping system that is piped downward from a drainage groove disposed around a sunroof of an automobile. In FIG. 1, the hose connection structure includes a connection joint 10, hoses 30 and 31 connected to both ends of the connection joint 10, and a hose 32 connected to a central portion of the connection joint 10. The hoses 30 and 32 are connected to a plurality of locations of drainage grooves of a sunroof (not shown), and the hose 31 is arranged to drain to the lower part of the vehicle body.

  The connection joint 10 is a joint branched in three directions, and is a joint manufactured by injection molding with a thermoplastic resin. The joint body 11 and an upstream hose connection portion 13 formed at one end of the joint body 11. And a downstream hose connection portion 14 formed at the other end of the joint body 11 and a branch connection portion 15 projecting from the central portion of the joint body 11, which are integrally formed. A main flow path 10Pa connected to the hoses 30 and 31 is formed in the joint body 11 and the hose connection sections 13 and 14, and a branch flow that is branched and connected to the main flow path 10Pa in the branch connection section 15. A path 10Pb is formed.

  FIG. 2 is an enlarged cross-sectional view of the vicinity of the hose connection portion 13 of FIG. The hose connection part 13 is a part for connecting the end of the upstream hose 30 and includes a hose clamping part 13a. The hose clamping unit 13a includes an inner circumferential clamping unit 13b and an outer circumferential clamping unit 13c. The inner periphery side holding part 13b and the outer periphery holding part 13c hold the flare 30b whose diameter is increased from the end of the hose body 30a of the hose 30. The inner periphery side clamping part 13b is laminated | stacked on the inner peripheral surface of the flare 30b. That is, the outer periphery clamping part 13c is laminated | stacked on the outer peripheral surface of the flare 30b. The inner peripheral side holding part 13b and the outer peripheral holding part 13c hold the flare 30b from the inner and outer peripheral surfaces, respectively. Here, if the inner diameter of the hose 30 is d1, and the inner diameter of the inner circumferential side holding portion 13b is d2, d1 = d2.

  The connection joint 10 and the hose 30 are formed of materials that are thermally welded to each other. That is, the connection joint 10 is formed of an olefin resin such as polypropylene (PP) or polyethylene (PE). The hose 30 is formed of an olefin-based thermoplastic elastomer (hereinafter referred to as TPO). TPO is a thermoplastic elastomer in which ethylene-propylene rubber (EPDM, EPM) is finely dispersed in polypropylene (PP). Therefore, both materials contain an olefinic resin such as polypropylene and are heat-welded to each other.

  In FIG. 1, the hose connecting portion 14 on the downstream side includes a connecting body 14a that protrudes in a cylindrical shape from the other end of the joint body 11, and an annular protrusion 14b that protrudes from the outer periphery of the connecting body 14a. . The hose 31 is press-fitted into the hose connection part 14. Thereby, the hose 31 is connected to the hose connection part 14 in a state of being prevented from being removed by the annular protrusion 14b. Moreover, the branch connection part 15 branches from the joint main body 11 and connects the hose 32 similarly to the hose connection part 14. The hose 32 can be used to collect rainwater or the like at a location different from the hose 30.

(2) Manufacturing method of hose connection structure In order to manufacture a hose connection structure, the following processes can be taken. First, the hose 30 is manufactured by an extrusion process using TPO. Thereafter, a jig is inserted into the end portion of the hose 30 and heated to braze the end portion of the hose 30 so that the flare 30b has an enlarged diameter. FIG. 3 is an explanatory view for explaining a manufacturing process of the hose connection structure. In FIG. 3, the flare 30 b portion of the hose 30 is set in the mold 40, and PP is injected into the cavity 41. Thereby, the connection joint 10 (FIG. 1) integrated in the flare 30b of the hose 30 by heat welding is formed. At this time, the flare 30b is clamped by the hose clamping portion 13a.

According to the hose connection structure according to the present embodiment, the following effects are obtained.
(3) -1 In FIG. 2, the inner diameter d <b> 1 of the hose 30 and the inner diameter d <b> 2 of the hose connection portion 13 are the same at the connection location of the hose 30 and the hose connection portion 13 of the connection joint 10. The inner wall and the inner wall of the hose connection portion 13 of the joint body 11 are flush with each other. That is, since there is no step at the connection location, rainwater or the like flows smoothly from the upstream of the hose 30 to the flow path of the connection joint 10 and does not stagnate as water droplets at the connection location. Therefore, even if the temperature in the vicinity of the hose connection structure becomes below freezing point, the flow path is not blocked due to freezing at the connection point.

(3) -2 The hose connection portion 13 of the connection joint 10 firmly connects the hose 30 by chemical bonding and mechanical bonding. That is, since the hose connecting portion 13 holds the flare 30b of the hose 30 from both the inner and outer peripheral sides by the inner peripheral side holding portion 13b and the outer peripheral holding portion 13c of the hose holding portion 13a, The hose 30 can be connected with bonding strength. Further, the hose is made of a thermoplastic elastomer (TPO) containing polypropylene (PP), and the connection joint 10 is made of polypropylene (PP). That is, since both members contain PP, they are heated to each other. Bonding strength is high due to chemical bonding.

(3) -3 The connection between the hose connection portion 13 of the connection joint 10 and the hose 30 is performed simultaneously with the injection molding of the connection joint 10 using the flare 30b of the hose 30 as an insert member, and thus the manufacturing process is also simple. .

(4) Other Examples FIG. 4 is a cross-sectional view showing a hose connection structure according to another example. The present embodiment is characterized by the configuration of the connection location between the connection joint 10B and the hose 30. The hose 30 includes a flare 30b whose diameter is expanded from the hose body 30a. The inner diameter d2-B of the inner peripheral side holding portion 13Bb of the hose holding portion 13Ba of the hose connection portion 13B is larger than the inner diameter d1 of the hose body 30a. Even with such a configuration, rainwater or the like can smoothly flow from the flow path of the upstream hose 30 to the flow path of the connection joint 10B, and problems such as blockage of the flow path do not occur.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations without departing from the spirit thereof.

DESCRIPTION OF SYMBOLS 10 ... Connection joint 10Pa ... Main flow path 10Pb ... Branch flow path 11 ... Joint main body 13 ... Hose connection part 13a ... Hose clamping part 13b ... Inner periphery side clamping part 13c ... Outer periphery clamping part 14 ... Hose connection part 14a ... Connection main body 14b ... Annular projection 15 ... Branch connection 30,31 ... Hose 30,32 ... Hose 30a ... Hose body 30b ... Flare

Claims (3)

A hose (30) formed from a thermoplastic elastomer, and the hose (30) as an insert member, and integrally molded with the hose (30) by injection molding a resin material that can be thermally welded to the hose (30). A connected joint (10),
The connection joint (10) has a hose connection part (13) for connecting the end of the hose (30),
When the inner diameter of the flow path of the hose (30) is d1, and the inner diameter of the flow path of the hose connection portion (13) is d2, the hose connection portion (13) is formed by d1 ≦ d2.
The hose connection structure, wherein the inner wall surface forming the flow path of the hose connection portion (13) is connected to the inner wall surface forming the flow path of the hose (30) by a flush or continuous curved surface. In the hose connection structure according to claim 1,
The hose connection structure in which the thermoplastic elastomer is an olefin thermoplastic elastomer, and the resin material of the connection joint (10) is an olefin resin. In the hose connection structure according to claim 1 or 2,
The hose (30) includes a flare (30b) having an enlarged diameter at the end of the hose (30).
The said hose connection part (13) is a hose connection structure provided with the hose clamping part (13a) clamped from the inner peripheral side and outer peripheral side of the said flare (30b).

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