JP4287714B2 - Hose connection structure and hose connection method - Google Patents

Description

  The present invention relates to a hose connection structure mainly used for a branch portion such as a two-way branch hose or a three-way branch hose, and particularly relates to a hose connection structure used for a branch portion such as a radiator hose or blow-by hose of an automobile.

  In recent years, the number of components to be mounted in a limited space in an engine room of an automobile tends to increase, and it has become more difficult to install various hoses for connecting these components. In such a case, it is very effective to use a branch hose that can save installation space.

(Prior art 1)
As such a branch hose, as shown in FIG. 2, a rubber hose 14 inserted through a nipple portion 12 of a resin hose joint 11 is placed in a mold, and a cover material such as resin or rubber is injection molded. By doing so, the thing of the structure which formed the coating layer 15 which coat | covers the rubber hose 14 and the hose joint 11 integrally is known (for example, refer patent document 1).

  In this branch hose, each rubber hose 14 is fastened to the nipple portion 12 by the binding pressure due to the injection pressure of the cover material and the contraction of the coating layer 15 during cooling.

  Furthermore, when a certain degree (1 atm or more) of sealing performance (air tightness) is required for the fastening portion, an adhesive is applied to the outer surface of the nipple portion 12 before the rubber hose 14 is inserted, and the inner surface of the rubber hose 14 is applied. Gluing is done.

  However, since the end face 14a of the rubber hose 14 is exposed before the branch hose is covered with the cover layer 15 made of the cover material, when the cover material is injected into the mold at high pressure, An injection pressure may be applied to the end surface 14a through the cover material, and so-called “disconnection” may occur in which the rubber hose 14 moves in a direction of disconnecting from the hose joint 11. When such omission occurs, the adhesive applied to the outer surface of the nipple portion 12 is peeled off to cause poor adhesion, resulting in a defective product without obtaining the required sealing performance.

  On the other hand, if the injection pressure is lowered to prevent such a drop, the cover material 15 is insufficiently filled with the cover material 15 and the end portion of the coating layer 15 becomes thin, and the fastening force is reduced. Insufficiency and sealability are deteriorated, and in this case, there is a problem that the product becomes defective.

  In order to prevent the nipple portion 12 from coming off, a groove such as a protrusion or a saw blade is provided on the outer surface of the nipple portion 12. In this case, the inner surface of the rubber hose 13 is protruded or saw blade when fastened or used. It is easy to be damaged by the pointed portion of the groove such as a shape, and there are often problems in durability and sealing performance.

(Prior art 2)
Moreover, as shown in FIG. 3, what provided the hook-shaped stopper 13 in the nipple part 12 with respect to the branch hose of the said prior art 1 is disclosed (for example, refer patent document 2).

  The stopper 13 is originally provided as a positioning role for defining the length for inserting the rubber hose 14 into the nipple portion 12. By providing such a stopper 13, when the rubber hose 14 is inserted into the nipple portion 12 until it contacts the stopper 13, the end surface 14 a of the rubber hose 14 is covered with one surface (contact surface) 13 a of the stopper 13 and exposed to the outside. Since it is not exposed, no injection pressure is applied to the end face 14a during the subsequent injection molding of the cover material, and the rubber hose 14 does not come off.

  However, at the time of injection molding of the cover material due to the presence of the stopper 13, the flow of the cover material is insufficient in the vicinity of the base portion 13c of the surface opposite to the stopper 13 (non-contact surface 13b). Air bubbles remain in the portion, the adhesion between the hose joint 11 and the coating layer 15 which is a solidified cover material is hindered, resulting in insufficient fastening force and poor sealing performance. is there.

(Prior art 3)
Further, instead of providing the hook-shaped stopper as described above, a configuration in which the outer diameter of the main body portion 16 of the hose joint 11 is larger than the outer diameter of the nipple portion 12 as shown in FIG. 4 is disclosed. (For example, see Patent Document 3).

  This configuration is also originally intended to position the rubber hose 14 when the rubber hose 14 is inserted into the nipple portion 12. With this configuration, when the rubber hose 14 is inserted into the nipple portion 12 until it contacts the end surface 16a of the main body portion 16, the end surface 14a of the rubber hose 14 is covered with the end surface 16a of the main body portion 16 and directly exposed to the outside. Therefore, no injection pressure is applied to the end face 14a during the subsequent injection molding of the cover material, and the rubber hose 14 does not come off. Further, as in the case where the bowl-shaped stopper 13 of the prior art 2 is provided, there is no portion where the flow of the cover material becomes insufficient, so no bubbles remain after injection molding, and sufficient fastening force And sealability can be obtained.

However, since it is necessary to make the outer diameter of the main body 16 larger than those of the prior arts 1 and 2, there is a problem that the material usage of the hose joint 11 having a high unit price increases and the manufacturing cost of the branch hose increases. .
Japanese Patent Laid-Open No. 6-58483 (paragraphs [0008] to [0012], FIG. 1) Japanese Patent Laid-Open No. 9-32988 (paragraph [0021], FIG. 1) JP 62-233591 A (page 3, FIG. 2)

  Therefore, an object of the present invention is to provide a hose connection structure and a hose connection method capable of obtaining a branch hose excellent in fastening force and sealing performance without increasing the manufacturing cost.

  The invention according to claim 1 is a hose joint provided with a plurality of nipple portions each having a ring-shaped stopper on an outer peripheral surface, a hose end portion positioned by the stopper and externally fitted to the nipple portion, and the hose end portion. A hose connection structure comprising a covering layer that integrally covers the hose end and the hose joint in a state of being externally fitted to the nipple portion, wherein one end of the stopper is an end surface of the hose end. The hose connection structure is characterized in that it is formed so as to cover the whole and the other surface is formed in a tapered shape.

  The invention according to claim 2 is the hose connection structure according to claim 1, wherein the coating layer is formed by injection molding a cover material made of resin or rubber.

  The invention according to claim 3 is the hose connection structure according to claim 1 or 2, wherein the end portion of the hose and the nipple portion are joined by an adhesive.

When the hose end is connected to a hose joint having a plurality of nipple portions having a ring-shaped stopper on the outer peripheral surface, the stopper has one surface over the entire end surface of the hose end. And the other surface is formed into a taper shape, and the hose end portion is externally fitted to the nipple portion until the end surface contacts the stopper, and then the hose end portion and the hose The joint is placed in a mold, and a cover material made of resin or rubber is injection-molded in the mold, so that the hose end and the hose joint are integrated with a cover layer formed of the cover material. It is a hose connection method characterized by covering.

  Since the present invention is configured as described above, the hose is not pulled out at the time of injection molding, and air bubbles do not remain near the base of the stopper after injection molding. It is possible to provide an excellent hose connection structure. Furthermore, the amount of material used for the hose joint with a high unit price can be made comparable to the prior arts 1 and 2, and the manufacturing cost is not increased. Therefore, a branch hose equipped with such a hose connection structure can be manufactured at low cost. Can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the hose connection structure according to the embodiment of the present invention includes a hose joint 1 having a plurality of nipple parts 2 each having a ring-shaped stopper 3 on the outer peripheral surface, and a stopper 3 positioned outside the nipple part 2. The hose end 4 is fitted, and the hose end 4 and the hose joint 1 are integrally covered with the hose end 4 in a state where the hose end 4 is externally fitted to the nipple portion 2. The stopper 3 is formed so that one surface, that is, the surface in contact with the end surface 4a of the hose end portion 4 (hereinafter referred to as “contact surface”) 3a covers the entire end surface 4a, and the other surface. It is assumed that the surface, that is, the surface opposite to the contact surface 3a (hereinafter referred to as “non-contact surface”) 3b is formed in a tapered shape.

  Thus, when the hose end 4 is inserted into the nipple portion 2 until it contacts the stopper 3 for positioning, the entire end surface 4a is completely covered with the contact surface 3a of the stopper 3, so that the portion directly exposed to the outside Does not exist. As a result, as in the prior arts 2 and 3, when the cover material is subsequently injection molded, no injection pressure is applied to the end surface 4a via the cover material, and the hose end portion 4 does not come off. In order to completely cover the entire end surface 4a of the hose end portion 4 with the contact surface 3a of the stopper 3, the outer diameter of the contact surface 3a of the stopper 3 needs to be the same as or larger than the outer diameter of the hose. If it is increased, it is necessary to increase the outer diameter of the cover layer 5 after injection molding of the cover material, which is not preferable from the viewpoint of saving installation space. Moreover, since the end surface 4a of the hose end portion 4 is usually formed by cutting perpendicularly to the axis of the hose, the contact surface 3a of the stopper 3 is also formed perpendicular to the axis of the hose joint 1 accordingly. It is good.

  Since the non-contact surface 3b of the stopper 3 is formed in a taper shape, the flow of the cover material does not become insufficient at the time of injection molding even in the vicinity of the base portion 3c of the non-contact surface 3b. Will not remain. Therefore, the covering layer 5 in which the cover material is solidified and the main body portion (a portion excluding the nipple portion 2) 6 of the hose joint 1 are sufficiently adhered, and an excellent fastening force and sealing performance can be obtained. In order to make the flow of the cover material smoother, it is desirable that the taper angle (inclination angle with respect to the parallel portion of the hose joint 1) is as small as possible, but the length of the main body portion 6 becomes too long, and the hose Since the amount of material used for the joint 1 increases and the manufacturing cost also increases, it is preferable that the range is 20 to 70 °, more preferably 30 to 60 °, and particularly 40 to 50 °. Note that the taper angle is not necessarily limited to a fixed one as shown in FIG. 1, and may be gradually changed in the longitudinal direction (that is, the taper's axial cross-sectional shape is not limited to a straight line, but a curved line). Or a polygonal line).

  The hose joint 1 may be made of metal because it requires a certain degree of rigidity, but a resin-made one is recommended from the viewpoint of weight reduction and corrosion resistance. In addition, as the cover material, a resin or rubber generally used for injection molding can be appropriately selected and used according to the purpose of use or the use environment.

  Furthermore, it is preferable to apply an adhesive to the outer surface of the nipple part 2 before inserting the hose end part 4 into the nipple part 2. With the above configuration, the hose end 4 does not come off, so that the adhesive is not peeled off when the cover material is injected, and the adhesion between the hose end 4 and the nipple 2 is maintained, and more complete. Sealing performance is ensured.

  In FIG. 1, the number of nipple portions 2 is three (that is, a two-way branch hose). However, the number of nipple portions 2 is not limited to this, and may be four (that is, a three-way branch hose) or more. Is applicable. Further, the present invention is not limited to the branch hose, and can naturally be applied to the case where the number of nipple portions is two (that is, when the hose is simply connected).

  The hose connection structure having the configuration shown in FIG. 1 can be formed as follows.

  After applying an adhesive to the nipple part 2 of the hose joint 1 as necessary, the hose end part 4 is inserted until it comes into contact with the stopper 3. Next, a joint portion composed of the hose end portion 4 and the hose joint 1 is disposed in a mold, and a cover material made of heat-melted resin or rubber is injected into the mold at a high pressure. The injected cover material is filled in the entire mold while discharging the air in the mold, and covers the exposed outer surfaces of the hose end 4 and the hose joint 1.

  At this time, since the contact surface 3a of the stopper 3 covers the entire end surface 4a of the hose end portion 4, the end surface 4a is not pressurized through the cover material, and the hose end portion 4 comes off. There is no. For this reason, even when an adhesive is applied to the nipple portion 2, the adhesive does not peel off.

  Further, since the non-contact surface 3b of the stopper 3 is formed in a tapered shape, the flow of the cover material does not become insufficient even in the vicinity of the base 3c of the non-contact surface 3b, and bubbles remain in this portion. There is no.

  The cover material filled in the entire mold is then cooled and solidified to become an integral coating layer 5, and further shrinks and contracts while being cooled to room temperature, and the hose end 4 is tightened to tighten the nipple portion 2. Since the coating layer 5 itself is in direct contact with the body portion 6 of the hose joint 1 at the same time, a hose connection structure having an excellent fastening force and sealability can be obtained.

In order to confirm the effect of the present invention, the following tests were conducted.
(Example)
As an example, a branch hose having a hose connection structure having the configuration shown in FIG. 1 was produced. The hose joint 1 was made of PA66 + GF 30 mass% synthetic resin, and the nipple part 2 and the main body part 6 had an outer diameter of 15 mm. The height of the stopper 3 is 4 mm, which is the same as the thickness of the rubber hose 4 to be connected, the surface 3a on the side in contact with the end surface 4a of the rubber hose 4 is perpendicular to the parallel part of the hose joint 1, and the opposite surface 3b is parallel. The taper was 45 ° with respect to the part. The length of the nipple portion 2 (that is, the length of the portion joined to the rubber hose 4) was 12 mm.
Then, after applying a rubber solvent adhesive to the nipple portion 2, the rubber hose 4 was inserted until the end surface 4 a abuts against the stopper 3. Next, this connecting portion is placed in a mold, and GR rubber melted at 180 ° C. as a cover material is injected into the mold at an injection pressure of 5 MPa, and cooled and solidified to form a coating layer 5 having an outer diameter of 23 mm. A branch hose was formed.
(Comparative example)
As a comparative example, a branch hose having a hose connection structure having the configuration shown in FIG. 2 was produced. The branch hose according to this comparative example has the same structure and size as the above example except that the stopper 3 is not provided, and the conditions for the injection molding of the cover material are also the same.
(Test results)
At the time of injection molding of the cover material, in the case of the comparative example, the rubber hose moved out by several mm, whereas in the case of the above example, no rubber hose was removed. Further, when an airtight test was performed on the produced branch hose, leakage occurred at 0.3 MPa in the branch hose of the comparative example, whereas no leak occurred even at 1.0 MPa in the branch hose of the example. . Furthermore, when the cross section of the fastening portion of the branch hose was observed, it was found that the adhesive between the nipple portion 2 and the rubber hose 4 was peeled off in the comparative example, whereas the adhesive was peeled off in the example. Was not observed at all, and a healthy joined state was maintained. In the example, no bubbles remained in the vicinity of the base 3c of the tapered surface 3b of the stopper 3.

It is sectional drawing explaining the schematic structure of the hose connection structure which concerns on implementation of this invention. It is sectional drawing explaining schematic structure of the hose connection structure of the prior art 1. FIG. It is sectional drawing explaining schematic structure of the hose connection structure of the prior art 2. FIG. It is sectional drawing explaining schematic structure of the hose connection structure of the prior art 3. FIG.

Explanation of symbols

1: Hose joint 2: Nipple part 3: Stopper 3a: Contact surface 3b: Non-contact surface 3c: Base part 4: Hose end part 4a: End face 5: Cover layer 6: Hose joint body part

Claims (4)

In a state where a hose joint having a plurality of nipple portions having a ring-shaped stopper on the outer peripheral surface, a hose end portion that is positioned by the stopper and is externally fitted to the nipple portion, and the hose end portion is externally fitted to the nipple portion. A hose connection structure comprising a covering layer that integrally covers the hose end and the hose joint,
The hose connection structure, wherein the stopper is formed so that one surface covers the entire end surface of the hose end portion, and the other surface is formed in a tapered shape. The hose connection structure according to claim 1, wherein the coating layer is formed by injection molding a cover material made of resin or rubber. The hose connection structure according to claim 1 or 2, wherein the end portion of the hose and the nipple portion are joined by an adhesive. When connecting the hose end to a hose joint provided with a plurality of nipple parts having a ring-shaped stopper on the outer peripheral surface,
The stopper is formed so that one surface covers the entire end surface of the hose end, and the other surface is tapered.
After the outer end of the hose is fitted on the nipple until its end surface comes into contact with the stopper, the end of the hose and the hose joint are placed in a mold, and the mold is made of resin or rubber. A hose connection method characterized by integrally covering the hose end portion and the hose joint with a coating layer formed of the cover material by injection molding a cover material.