JPH06190974A - Double-layered hose - Google Patents

Abstract

PURPOSE:To provide an inexpensive hose excellent in gasoline permeability resistance and also good in sealability when a pipe is inserted in the end part of the hose to be connected to the hose. CONSTITUTION:The hose 10 connected to a pipe 16 in such a state that the pipe 16 is inserted in the end part 18 of the hose 10 is formed as a laminated structure consisting of a rubber outer layer 20 and a thin-walled inner layer 22 composed of a resin or metal and the inner layer 22 is formed excepting the end part 18 of the hose. Or, the inner layer 22 is continuously formed to the respective inner surfaces of the central part 14 and end part 18 of the hose 10 and the inner layer 22 at the end part 18 is made thinner than that at the central part 14 of the hose.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layer hose suitable as a filler hose for automobiles.

[0002]

2. Description of the Related Art A filler hose (fuel hose) for an automobile is conventionally formed of a rubber material such as NBR / PVC rubber which is resistant to gasoline and permeable to gasoline. However, regulations on gasoline permeation have become stricter in recent years, and it has become difficult to satisfy the regulation on gasoline permeation resistance with the conventional hose made of only rubber.

Therefore, as shown in FIG. 25, one having an inner layer 102 made of thin fluororubber on the inner peripheral surface of an outer layer 100 made of rubber is considered. Although the hose having the inner layer 102 formed of this fluororubber has good performance, it has a problem of high cost, and is practically difficult to adopt. On the other hand, in the hose for transporting the refrigerant, as shown in FIGS. 26 and 27, the inner layer 1 made of a thin resin is formed on the inner peripheral surface of the outer layer 100 made of rubber.
A structure in which 04 is stacked is known.

Applying this laminated structure to a filler hose,
By stacking the inner layer 104 formed of a resin having excellent gasoline resistance and gasoline permeation resistance on the inner peripheral surface of the outer layer 100, it is possible to obtain gasoline resistance and gasoline permeation resistance while ensuring flexibility required for a hose. It can be expensive and inexpensive. In this case, a hard resin material is used as the resin forming the inner layer 104, and this is formed with a constant wall thickness necessary for ensuring gasoline resistance and gasoline permeation resistance. This is because at present, hard resin materials are generally superior in performance such as gasoline resistance to soft resin materials.

In the conventional hose having this laminated structure, a resin tube (inner layer 104) is first extruded as shown in FIG.
0) is extrusion-molded and laminated, and the rubber tube is vulcanized in that state, or is once semi-vulcanized and subjected to a predetermined bending process, and then vulcanization is performed to obtain a bending hose shown in FIG. 28. . The inner layer 104 formed of resin on the inner surface side of the laminated structure of the hose has a uniform thickness at both the center and the end of the hose.

By the way, in the case of a filler hose, since a mating pipe made of metal is inserted inside the end of the hose for connection, a hard resin inner layer is formed inside the end of the hose with a constant wall thickness. When the mating pipe is inserted, the adhesion may be insufficient and sufficient sealing may not be obtained.

[0007]

The invention of the present application has been made to solve such a problem. The multi-layer hose of the present invention comprises an outer layer made of rubber and an inner layer integrally made of resin or metal on the inner peripheral surface of the outer layer, and a mating member is inserted inside the end to be connected. The multi-layer hose is characterized in that the inner layer is formed on an inner peripheral surface of a central portion of the hose excluding an end portion into which the mating member is inserted.

The inner layer of the other multi-layer hose of the present invention is formed on the center portion of the outer layer and on the inner peripheral surface of the end portion into which the mating member is inserted, and the inner layer of the inner peripheral surface of the end portion into which the mating member is inserted. The thickness of the portion is thinner than the thickness of the portion formed on the inner peripheral surface of the central portion of the hose. The inner layer of yet another multilayer hose of the present invention is characterized in that it is formed on the inner peripheral surface of the central portion of the outer layer and a part of the inner peripheral surface from the central portion of the end portion into which the mating member is inserted.

The multi-layer hose of the present invention is composed of an end portion forming both side portions and a central portion connecting both end portions when viewed in the axial direction. The end is a portion into which a nipple made of metal or hard resin is inserted and fixed. The central portion is a portion that should be called a hose body, and is formed in a straight shape, a curved shape, or a bellows shape having a constant diameter. When the multi-layer hose of the present invention is used as a filler hose for automobiles and its inner layer is made of resin, the resin has a gasoline permeation constant of 5 mg.
・ It is recommended to have excellent gasoline permeation resistance of less than mm / cm ² · day. More preferably, the gasoline permeation constant is 1 mg · mm / cm ² · day, and more preferably the gasoline permeation constant is 0.3 mg · mm / cm ² · day or less, which has excellent gasoline permeation resistance.

Here, the gasoline permeation constant means that gasoline is put in a cup, a resin film (thickness 1 mm) is attached on the upper surface so that the gasoline does not leak, and the resin film is in contact with the liquid in an atmosphere of 60 ° C. After standing, the weight loss is measured every 24 hours, and the resin film is 1m when the value is stable.
Weight reduction per m and surface area 1 cm ² (mg ・ mm /
cm ² · day).

When the inner layer of the multi-layer hose of the present invention is made of resin, the inner layer has a wall thickness of 0.01 to 1 m.
m, preferably 0.05 to 0.7 mm, more preferably 0.1 to 0.4 mm. When an inner layer made of a thin resin is provided on the inner peripheral surface of the end of the hose, the wall thickness thereof is preferably 0.1 mm or less, more preferably 0.05 mm or less. On the other hand, when the inner layer is made of metal, the thickness of the inner layer is preferably 0.2 mm or less, more preferably 0.15 mm or less.

Further, the wall thickness of the inner layer at the end portion may be gradually reduced as the distance from the boundary portion between the hose center portion and the end portion is increased. Further, the inner layer formed on the inner peripheral surface of the end portion may be a part of the inner peripheral surface of the end portion from the central portion. When the thickness of the resin inner layer on the inner surface side of the end of the hose is set as described above, it is possible to more effectively prevent stress from concentrating on the end surface portion of the resin inner layer.

However, the multi-layer hose of the present invention can be used as a hose for other purposes than the filler hose for automobiles. Although the outer layer is made of rubber, the outer layer may be a single rubber layer or a plurality of rubber layers. Also,
It is also possible to embed a reinforcing thread and a reinforcing cloth in the rubber layer.

[0014]

One of the multi-layer hoses of the present invention has no inner layer formed of resin or metal on the inner peripheral surface of the end of the hose into which the mating member is inserted. In the other multi-layer hose, an inner layer formed of resin or metal exists on the inner peripheral surface of the central portion of the outer layer and a part of the inner peripheral surface of the end portion from the central portion. Further, in the other multi-layer hose, the inner layer is present on the entire inner peripheral surface of the end portion together with the inner peripheral surface of the central portion of the outer layer, but the inner layer formed on the inner peripheral surface of the end portion is thin.

Since the inner layer formed of resin or metal does not exist or is a thin inner layer on the inner peripheral surface of the hose end, when the mating member is inserted into the hose end, the inner surface of the hose end and the mating member are inserted. Can be closely adhered to each other, and a sufficient sealing property at the connection end can be secured. Moreover, since the inner surface side of the hose end portion is hidden by the insertion and fitting of the mating member, there is little problem that the inner fluid side is greatly deteriorated by the internal fluid such as gasoline or the permeation of gasoline or the like becomes large.

That is, the multi-layer hose of the present invention is excellent in gasoline resistance, gasoline permeation resistance and economical efficiency, and also has a good sealing property at the end. The multi-layer hose in which the inner layer on the inner peripheral surface side of the end portion into which the mating member is inserted of the present invention is thinned or the inner layer is formed only in a part from the central portion is formed on the inner peripheral surface of the end portion into which the mating member is inserted. Since the resin has an inner layer, the sealing property is deteriorated. However, since the hose has an inner layer at both the center and the end, the following problems of a hose having no inner layer at the end are less likely to occur. With a hose that does not have an inner layer at the end,
Stress concentration occurs due to a difference in physical properties between the resin and the rubber at or near the boundary between the resin and the rubber on the inner peripheral surface, or the action of the internal fluid is greatly different. As a result, the end surface portion of the resin inner layer may easily peel off from the rubber outer layer.

In the multi-layer hose of the present invention, since the resin inner layer at the end portion is thinned or the inner layer is formed only at a part of the end portion, the followability to the outer layer formed of rubber is good, Moreover, since this portion is a portion sandwiched between the outer rubber layer and the mating member, it is possible to effectively prevent the end face peeling due to the stress concentration on the end face portion of the resin inner layer and the action of the internal fluid.

Moreover, since the resin inner layer at the end of the hose is thin or is formed only partially, the flexibility of the end is not lost, and therefore a good sealing property can be secured.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. Example 1 The multilayer hose 10 of Example 1 is shown in FIG. In addition, in FIG. 1, the left half is shown as a cross section, and a nipple 16 of a mating material is attached to the upper end portion.

The multi-layer hose 10 is used as a filler hose for automobiles through which gasoline flows. The multi-layer hose 10 has an inner diameter of 34 mm, and is composed of a central portion 14 having a bellows-shaped portion 12 and an end portion 18 into which a nipple 16 formed of a mating metal pipe is inserted and fixed. This multi-layer hose 10 is composed of an outer layer 20 made of rubber and an inner layer 22 made of resin integrally bonded to the inner peripheral surface of the central portion 14 of the outer layer 20. An adhesive layer (not shown) is interposed between the outer layer 20 and the inner layer 22.

Here, as the rubber constituting the outer layer 20,
A rubber material such as NBR / PVC, CR, CHC, CSH, EPDM is used. Further, the outer layer 20 may be formed as a single rubber layer or may be formed of multiple rubber layers. When the outer layer 20 is a multi-layer, for example, rubber having excellent gasoline resistance can be arranged on the inner surface side of the outer layer and rubber having excellent fire resistance or abrasion resistance can be arranged on the outer surface side. In such a case, the multi-layer hose is excellent not only in gasoline resistance but also in fire resistance or abrasion resistance.

As the resin constituting the inner layer 22, polyamide-based, fluorine-based, polyester-based, polyvinyl chloride-based, polyacetal-based, PPS-based, etc. having excellent gasoline resistance and gasoline permeation resistance (gasoline permeation constant of 1 mg・
(mm / cm ² · day or less) Resin is used. The inner layer 22 may be made of metal instead of resin. In the case of the multi-layer hose 10 of the present embodiment, the hose central portion 14 that is directly exposed to the internal fluid has a laminated structure of the outer layer 20 made of rubber and the inner layer 22 made of thin resin, and has a bellows shape. ing. Therefore, the hose central portion 14 effectively blocks the permeation of gasoline by the inner layer 22 made of resin while maintaining good flexibility. On the other hand, the hose end 1
In No. 8, the inner layer 22 is not formed, and the outer layer 20 formed of a flexible rubber directly fits the nipple 16 on the mating side and is sufficiently adhered to seal the connection portion well.

That is, the hose 10 of this example has the flexibility required for a hose, good gasoline resistance, gasoline permeation resistance, and good connection and sealability with the mating metal pipe 16. In the multi-layer hose 10 of this embodiment, the inner layer 22 is not formed on the inner surface of the end portion 18, but
Since the inner surface of is fitted into the metal pipe 16 on the other side and does not come into direct contact with gasoline or the like inside, there is no concern that gasoline or the like will permeate outside through the hose end portion 18 even if the inner layer 22 is not formed.

The central portion 14 of the hose 10 according to this embodiment has the outer layer 2
0 and the inner layer 22 are bonded to each other, the hose 10
There is no problem that the outer layer 20 and the inner layer 22 are separated due to the negative pressure acting on the inside, the vibration applied to the hose 10, and the deformation of the hose 10 itself. Here, as a method of adhering the outer layer 20 formed of rubber and the inner layer 22 formed of resin, a method of applying an adhesive to the inner surface of the outer layer 20 in advance prior to the lamination of the inner layer 22, the outer layer 20 and / or Inner layer 22
A method of kneading (compounding) an adhesive with the rubber and / or the resin constituting the above is possible.

In the multi-layer hose 10 of this embodiment, a core metal (not shown) having the same shape as the hose hole is used, and a resin film forming the inner layer 20 is formed on the outer peripheral surface of the core metal. After this, the resin surface is coated with an adhesive. Next, a core metal having this resin film is coated with a predetermined unvulcanized rubber, housed in a mold and heated to be vulcanized and molded. In order to take out the multi-layer hose obtained from the metal mold and the core metal, a combination mold having a plurality of parts is used for the metal mold and the core metal. A method of activating the resin film instead of coating the resin film with an adhesive is also effective. As such an activation method, a known activation treatment such as sodium etching treatment, surface oxidation treatment with plasma flame or the like, or physical treatment such as sputtering can be employed. When the resin surface is activated, the rubber is vulcanized and adhered to the resin surface, and a strong bond is achieved between the resin and the rubber.

As another manufacturing method, first, the outer layer 2
The rubber forming 0 is injection-molded, the end portions of the inner peripheral surface of the obtained rubber molded body are masked, and only the inner peripheral surface of the central portion is resin powder coated in the same manner as electrostatic powder coating. To cover. After that, the entire hose is heated to melt the resin powder and integrate it to form an inner layer. In this method, the rubber molded body forming the outer layer may be vulcanized at the time of molding or unvulcanized only simply molded. In the latter case, vulcanization is carried out by utilizing the heating when the resin powder of the inner layer is melted and integrated.

Embodiment 2 FIG. 2 shows a cross section of a main part of a multi-layer hose 10 of a second embodiment, and FIG. 3 shows a cross section of a main part with a nipple 16 as a mating member attached to its end. In the multi-layer hose 10, the end portion 18 has a smaller inner peripheral diameter than the central portion 14, and the wall thickness of the end portion 18 is increased accordingly, and the central portion 14 and the end portion 1 are
8 and a low step 24 is provided. The inner layer 22 made of resin is formed so that its end surface abuts on the step 24 on the inner peripheral surface of the outer layer 20 made of rubber.

In the multi-layer hose 10 of this embodiment, since the end surface of the inner layer 22 is covered with the step 24 on the inner peripheral surface of the outer layer 20, the inner layer 22 is less likely to peel off from the end surface. Further, as is apparent from FIG. 3, the enlarged diameter portion of the outer peripheral surface of the tip portion of the nipple 16 engages with the end of the central portion 14. At this time, since the inner diameter of the central portion 14 is larger than that of the end portion 18, the diameter of the inner layer 22 at the end of the nipple 16 is less expanded and the expansion of the inner layer 22 is reduced accordingly.

The multi-layer hose 10 of this embodiment can also be manufactured by the method described in the first embodiment. Example 3 FIG. 4 shows a cross section of a main part of a multi-layer hose 10 of a third embodiment, and FIG. 5 shows a cross section of a main part in a state where a nipple 16 as a mating member is attached to the end part thereof. This multi-layer hose 10 has a temporary inner peripheral diameter increasing from the central portion 14 toward the end portion 18 shown in FIG. 4 at the boundary portion between the end portion 18 and the central portion 14 of the outer layer 20 formed of rubber, A ring groove 25 having a cross-sectional shape in which the inner peripheral diameter is reduced substantially at the side of the portion 18 is formed. Then, the inner layer 22 made of resin is formed together with the central portion 14 of the outer layer 20 up to the maximum inner diameter of the ring groove 25, and the end face of the inner layer 22 is abutted against the inner wall of the ring groove 25 which stands substantially at a right angle. It is formed by contact.

The multi-layer hose of this embodiment is also the same as the multi-layer hose of the second embodiment, in which the inner layer 22 is less likely to be peeled off from its end face, and the degree of diameter expansion by the tip of the nipple 16 at the end of the inner layer 22 is small. This has the effect of reducing the expansion of the inner layer 22. Example 4 FIG. 6 shows a cross section of a main part of a multi-layer hose 10 of a fourth embodiment, and FIG. 7 shows a cross section of a main part in a state where a nipple 16 as a mating member is attached to the end part thereof.

The multi-layer hose 10 has a trapezoidal cross-section on the inner peripheral surface in the direction from the central portion 14 to the end portion 18 shown in FIG. 6 at the boundary portion between the end portion 18 and the central portion 14 of the outer layer 20 formed of rubber. It has a ring-shaped ridge 26 that makes one round and a ring groove 25 as described in the third embodiment. Then, the inner layer 22 made of resin is formed along with the central portion 14 of the outer layer 20 with the ridges 26.
And the innermost diameter of the ring groove 25 are formed to the inner layer 2
The end surface of No. 2 is formed by abutting against the inner wall of the ring groove 25 which stands at a substantially right angle.

In the multi-layer hose of this embodiment, as in the multi-layer hoses of the second and third embodiments, the inner layer 22 rarely peels off from the end face of the inner layer 22 and the nipple 1 at the end of the inner layer 22.
The degree of diameter expansion due to the tip of 6 is small,
It has the effect of reducing the expansion of. Further, the tip of the nipple 16 is brought into contact with the side surface of the ring-shaped ridge 26 and locked. Therefore, the degree of insertion of the nipple 16 can be surely known, and a defect due to insufficient insertion of the nipple 16 can be prevented. Then, the engagement between the multi-layer hose 10 and the nipple 16 becomes more reliable. Further, since the hose 10 at the tip end side of the nipple 16 is formed by the protrusions 26 and has the thickest wall, which is likely to receive stress concentration when the nipple 16 is inserted and fixed, durability of the hose 10 is improved. Sex increases.

In this embodiment, the ridge 26 is formed in a ring shape so as to go around the inner peripheral surface once. However, for example, the ridge 26 may be divided into two or three parts at intervals in the circumferential direction, or instead of the ridge. It may be a plurality of protrusions arranged in the circumferential direction. Example 5 FIG. 8 shows a cross section of a main part of a multi-layer hose 10 of a fifth embodiment, and FIG. 9 shows a cross section of a main part in a state where a nipple 16 which is a mating member is attached to the end part thereof.

In the multi-layer hose 10, the end portion 18 has a larger inner peripheral diameter than the central portion 14, the wall thickness of the end portion 18 is made thinner, and the end portion 18 and the central portion 14 have a lower diameter. A step 27 is provided. The inner layer 22 made of resin is formed only on the inner peripheral surface of the central portion 14, and the end surface of the inner layer 22 constitutes the step portion 18 together with the outer layer 20 made of rubber.

Since the multi-layer hose 10 of this embodiment has the low step 27 between the end portion 18 and the central portion 14, when the nipple 16 is inserted and fixed to the end portion 18, the tip of the nipple 16 is fixed. Contacts the end surface of the step 27. As a result, the end surface of the inner layer 22 also comes into contact with the tip of the nipple 16, and the fluid flowing directly into the hose 10 is formed of rubber.
I try not to touch 0. In this embodiment, since the end portion 18 is thinner than the central portion 14, the nipple 16 can be easily attached and detached.

The multi-layer hose 10 of this embodiment can also be manufactured by the method described in the first embodiment. Sixth Embodiment FIG. 10 shows a cross section of a main part of a multi-layer hose 10 of a sixth embodiment, and FIG. 11 shows a cross section of a main part in a state where a nipple 16 which is a mating member is attached to an end portion thereof. This multi-layer hose 10
A ring-shaped ridge 28 protruding toward the inner peripheral surface is provided on the end portion 18 side of the central portion 14, and the end surface on the end portion 18 side is formed as a step 27 perpendicular to the axis. The inner layer formed of resin is formed on the inner peripheral surface of the central portion 14 including the protrusions 27 except the end surface of the step 27. The central portion 14 and the end portion 18 of the outer layer 20 made of rubber have the same thickness except for the protrusion 27. The multi-layer hose 10 of this embodiment has the same function and effect as the multi-layer hose of the fifth embodiment. Further, since the ridge 27 having a thicker wall is provided, the multi-layer hose and the nipple are surely connected to each other and the durability of the hose 10 is high, as in the multi-layer hose of the fourth embodiment.

Embodiment 7 FIG. 12 shows a cross section of a main part of a multi-layer hose 10 of a seventh embodiment, and FIG. 13 shows a cross section of a main part with a nipple 16 as a mating member attached to the end thereof. This multi-layer hose 10
A ring-shaped convex piece 31 having a small axial thickness is formed at the boundary between the end portion 18 and the central portion 14. The end surface of the inner layer 22 made of resin is formed so as to contact the side surface of the convex piece 31.

As shown in FIG. 13, the convex piece 31 is pushed by the tip of the nipple 16 and covers the end portion of the inner layer 22. In other words, the convex piece 31 is interposed between the end portion of the inner layer 22 and the tip portion of the nipple 16 and seals the both. Therefore, the fluid leaking along the surface of the nipple 16 is more reliably prevented. The multi-layer hose 10 of this embodiment can also be manufactured by the method described in the first embodiment.

Example 8 FIG. 14 shows a cross section of a main part of the multi-layer hose 10 of the eighth embodiment, and FIG. 15 shows a cross section of a main part with a nipple 16 as a mating member attached to the end thereof. This multi-layer hose 10
At the boundary portion between the end portion 18 and the central portion 14 of the outer layer 20 formed of rubber, the inner peripheral surface is formed in the same manner as the ring-shaped groove 25 that goes around the inner peripheral surface from the central portion 14 toward the end portion 18 in FIG. A ring-shaped convex piece 31 is formed so as to make a round, and the end of the inner layer 22 made of resin is positioned at the bottom of the ring-shaped groove 25. The ring-shaped groove 25 and the ring-shaped convex piece 31 are both concave or convex in the direction inclined with respect to the axis of the hose 10.

This convex piece 31 also functions as a seal like the convex piece of the seventh embodiment. A ring-shaped groove 25 having an end of the inner layer 22
Since it extends to the bottom and its diameter increases toward the end, even if the nipple 16 is inserted and fixed, the nipple 16 is less likely to be deformed by the tip portion thereof, and the durability is increased. Further, it becomes possible to widen the seal width by the convex piece 31, and the sealability is improved accordingly.

Embodiment 9 FIG. 16 shows a cross section of a main part of a multi-layer hose 10 of a ninth embodiment, and FIG. 17 shows a cross section of a main part in a state where a nipple 16 which is a mating member is attached to the end of the multi-layer hose. This multi-layer hose 10
At the boundary between the end portion 18 and the central portion 14 of the outer layer 20 formed of rubber, a ring-shaped protrusion 26 that goes around the inner peripheral surface and a ring-shaped groove 25 that goes around the inner peripheral surface shown in FIG. 14
A ring-shaped convex piece 31 that goes around the inner peripheral surface shown in FIG. 1 is formed, and the surface of the protrusion 26 is covered with the inner layer 22 made of resin, and its end is located at the bottom of the ring-shaped groove 25. Is.

This convex piece 31 also functions as a seal like the convex piece of the seventh embodiment. A ring-shaped groove 25 having an end of the inner layer 22
Since it extends to the bottom and its diameter increases toward the end, even if the nipple 16 is inserted and fixed, the nipple 16 is less likely to be deformed by the tip portion thereof, and the durability is increased. Further, it becomes possible to widen the seal width by the convex piece 31, and the sealability is improved accordingly. Further nipple 16
Since the projecting ridge 26 having a thick wall is located on the tip side of the nipple 16 into which is inserted and fixed, the multi-layer hose and the nipple are securely coupled to each other as in the multi-layer hose of the fourth embodiment. The durability is improved.

Embodiment 10 FIG. 18 shows a cross section of a main part of a multi-layer hose 10 of the tenth embodiment, and FIG. 19 shows a cross section of a main part in a state where a nipple 16 which is a mating member is attached to an end portion thereof. This multi-layer hose 10
Is a ridge formed at a slight distance from the convex piece of the hose shown in FIG. 12 to the central portion in the axial direction. That is,
At the boundary between the end portion 18 and the central portion 14 of the outer layer 20 formed of rubber, a ring-shaped protrusion 26 that goes around the inner peripheral surface shown in FIG. 6 and a ring-shaped protrusion that goes around the inner peripheral surface shown in FIG. Convex piece 3
1 is formed, and the end surface of the inner layer 22 made of resin is brought into contact with the side surface of the convex piece 31.

This convex piece 31 also functions as a seal like the convex piece of the seventh embodiment. Further, the ridge 26 having a thick wall is provided on the tip side of the nipple 16 into which the nipple 16 is inserted and fixed.
Is located, the durability of the hose 10 is improved. Example 11 A cross-sectional view of a multilayer hose 30 according to an example of the present invention is shown in FIG. The nipple 16 is inserted and fixed to the right end portion 38 of the multi-layer hose 30. This multi-layer hose 30
Is composed of a hose central portion 36 having a bellows-shaped portion 31, and both end portions 38 into which the mating metal pipe 16 is inserted. Each of the central portion 36 and the end portion 38 has a laminated structure of an outer layer 32 made of rubber and an inner layer 34 made of resin.

The inner layer 34 includes the hose central portion 36 and the end portion 3.
8 is formed on the entire inner peripheral surface. The inner layer 34 of the end portion 38 has a thickness (for example, 0.1 mm or less) as shown in FIG.
It is thinner (for example, 0.05 mm) than 5 mm. By thus forming the resin inner layer 34 also on the hose end portion 38 and making it thinner than that of the hose central portion 36, stress acting on a portion where stress concentration is likely to occur due to the nipple 16 that is inserted and fixed. It is possible to effectively prevent the inner layer 34 from peeling off due to concentration or the action of the internal fluid.

Since the resin inner layer 34 at the end portion 38 is thin, it is highly flexible. Therefore, the resin inner layer 34 of the end portion 38 can be easily deformed together with the rubber outer layer 32.
Further, the sealing property when the nipple 16 is inserted and fixed in the end portion 38 is also good. This resin inner layer 3 of the hose end 38
No. 4 is, as shown in FIG.
The wall thickness can be gradually reduced as the distance from the hose central portion 36 increases, and in this case, the end face peeling of the resin inner layer 34 can be prevented even better.

Embodiment 12 FIG. 23 shows a partial sectional view of the upper half of the multi-layer hose 40 of the embodiment of the present invention. In addition, this multi-layer hose 40
A nipple 16 made of a metal pipe on the other side is inserted and fixed to the left end portion 48 of the. This multi-layer hose 40
Is composed of a hose central portion 46 having a bellows-shaped portion 41 and both end portions 48 into which the mating nipple 16 is inserted. The central portion 46 is an outer layer 42 made of rubber.
And an inner layer 44 made of metal.

The inner layer 44 is formed by subjecting a thin pipe of stainless steel to plastic working, and the center portion thereof is formed into a bellows shape, and both end portions thereof are first formed as ring-shaped protrusions 45 protruding toward the inner surface side, and the axial opening thereof is formed. On the side, a rounded opening end 47 whose inner diameter gradually increases is formed. In the outer layer 42, a reinforcing cloth 43 formed by knitting a reinforcing thread is embedded in the center of the layer. At the boundary between the end portion 48 of the outer layer 42 and the central portion 46, a ring-shaped protrusion that projects in the axial direction toward the end surface side of the opening end 47 of the inner layer 44 and that makes a turn around the inner peripheral surface inclined toward the central portion 46. The piece 49 is formed.

The ring-shaped projections 45 provided on the inner peripheral surfaces on both ends of the inner layer 44 are inserted and fixed to the mating nipple 16.
Serves as a stopper. The open end 47 in the shape of a sulcus receives the ring-shaped ridge projecting toward the outer periphery on the tip side of the nipple 16. Further, the ring-shaped convex pieces 49 of both end portions 48 of the outer layer 42 are pushed by the tip portion of the nipple 16, and are sandwiched between the tip portion of the nipple 16 and the rod-shaped opening end 47 of the inner layer 44 to form a seal. Play a role.

Since the inner layer 44 of the multi-layer hose 40 is made of metal, it does not permeate gasoline. Further, since the reinforcing cloth 43 is embedded in the outer layer 42, the strength is high. Further, the nipple 16 is surely inserted and fixed in a predetermined position by the ring-shaped protrusion 45, the boss-shaped opening end 47, and the ring-shaped convex piece 49, and the inner layer 44 and the nipple 16 are sealed.

Embodiment 13 FIG. 24 is a partial sectional view showing the upper half of the multi-layer hose 50 of the embodiment of the present invention. In addition, this multi-layer hose 50
The nipple 16 made of a metal pipe on the opposite side is inserted and fixed to the left end portion 58 of the. This multi-layer hose 50
Is composed of a hose central portion 56 having a bellows-shaped portion 51 and both end portions 58 into which the mating nipple 16 is inserted. The central portion 56 is an outer layer 52 made of rubber.
And an inner layer 54 made of metal. The both end portions 58 are mainly composed of an outer layer 52 made of rubber, and the axial center portions 56 of the both end portions 58 are formed.
An inner layer 54 is provided on the inner peripheral surface of almost half of the side.

The inner layer 34 is formed by subjecting a thin pipe of stainless steel to plastic working, and has a bellows shape at its center and a straight tube 57 having a constant inner peripheral diameter at both ends. The inner diameter of the straight pipe 57 is equal to that of the nipple 16 on the other side.
Is slightly larger than the outer peripheral diameter of the tip end portion of the nipple 16. The outer layer 52 is formed of laminated rubber in which two types of rubber layers are laminated. The outer layer 52 is integrally vulcanized and bonded to the outer peripheral surface of the inner layer 54. A ring-shaped protrusion 53 is provided on the outer peripheral surface of the outer layer 52 at the boundary with the center of the end 58 of the outer layer 52. The protrusion 53 serves as a mark indicating the tightening position of the fixing band 161.

Since the inner layer 54 of the multi-layer hose 50 is made of metal, it does not permeate gasoline. Further, since the outer layer 52 is formed of laminated rubber, it is possible to easily impart characteristics such as abrasion resistance of the multilayer hose 50. Moreover, since the inner layer 54 extends to the middle of the end portion 58 in the axial direction, the inner layer 5 is directly connected.
4 and the nipple 16 are fitted together. Therefore, the nipple 1
The strength of the multi-layered hose 50 portion corresponding to the 6 end is strong and is highly practical. Further, the half of the end portion 58 on the opening side is directly connected to the outer layer 5.
Since the rubber 2 is exposed, the sealability with the nipple 16 is also high. In addition, as shown in FIG.
Alternatively, the fixing band 161 may be tightened.

Although the embodiment of the present invention has been described in detail above, this is merely an example. The present invention is, for example, a hose having a shape shown in FIG. 23, that is, a hose having a shape bent at a predetermined portion 32 and a bellows-shaped portion 12 is partially provided in the center of the hose, and various other shapes. Alternatively, it can be applied to a hose for various purposes, and various modifications can be made based on the knowledge of those skilled in the art without departing from the spirit of the invention.

[Brief description of drawings]

FIG. 1 shows a cross section of a multilayer hose of Example 1.

FIG. 2 is a cross-sectional view of an essential part of a multilayer hose of Example 2.

FIG. 3 is a cross-sectional view of an essential part of a state in which a nipple that is a mating member is attached to the end of the multilayer hose of Example 2.

FIG. 4 is a cross-sectional view of an essential part of a multilayer hose of Example 3.

FIG. 5 is a cross-sectional view of essential parts in a state in which a nipple that is a mating member is attached to the end of the multilayer hose of Example 3.

FIG. 6 is a cross-sectional view of an essential part of a multilayer hose of Example 4.

FIG. 7 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multilayer hose of Example 4.

FIG. 8 is a cross-sectional view of the main parts of the multilayer hose of Example 5.

FIG. 9 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to an end portion of the multilayer hose of Example 5.

FIG. 10 is a cross-sectional view of the main parts of the multi-layer hose of Example 6.

FIG. 11 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multi-layer hose of Example 6.

FIG. 12 is a cross-sectional view of an essential part of a multilayer hose of Example 7.

FIG. 13 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multilayer hose of Example 7.

FIG. 14 is a cross-sectional view of the main parts of a multilayer hose of Example 8.

FIG. 15 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multilayer hose of Example 8.

FIG. 16 is a cross-sectional view of the main parts of the multilayer hose of Example 9.

FIG. 17 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multilayer hose of Example 9.

FIG. 18 is a cross-sectional view of the main parts of the multilayer hose of Example 10.

FIG. 19 is a cross-sectional view of essential parts in a state where a nipple that is a mating member is attached to the end of the multilayer hose of Example 10.

FIG. 20 is an overall cross-sectional view of the multi-layer hose of Example 11 in which a nipple that is a mating member is attached to the end.

FIG. 21 shows an enlarged cross-section of the end of the multi-layer hose of Example 11.

FIG. 22 is an enlarged cross-sectional view of an end portion of a modified example of the multilayer hose of Example 11.

23 is an overall view showing a cross section of the upper half of the multilayer hose of Example 12. FIG.

24 (A) and (B) are overall views showing the upper half of the multilayer hose of Example 13 in cross section.

FIG. 25 is a perspective view showing an example of the outer shape of the multilayer hose of the present invention.

FIG. 26 is a partial cross-sectional view of a conventional multi-layer hose.

FIG. 27 is an overall cross-sectional view of another conventional multi-layer hose.

FIG. 28 is an overall sectional view of still another conventional multi-layer hose.

FIG. 29 is a sectional view illustrating a conventional method for manufacturing a multi-layer hose.

[Explanation of symbols]

 10, 24, 30, 40, 50 Multi-layer hose 12 Bellows-shaped portion 14, 26, 36, 46, 56 Central portion 16 Nipple 18, 28, 38, 48, 58 End portion 20, 32, 42, 52 Outer layer 22, 34, 44, 54 Inner layer

Claims (3)

[Claims] 1. A multi-layer hose comprising an outer layer formed of rubber and an inner layer integrally formed on the inner peripheral surface of the outer layer with resin or metal, and a mating member is inserted inside the end portion to be connected. The multi-layer hose, wherein the inner layer is formed on the inner peripheral surface of the center of the hose excluding the end into which the mating member is inserted. 2. A were or integrally resins on the inner peripheral surface of the outer layer and the outer layer formed by rubbers and an inner layer made of a metal, double that on the inside end mating member are connected is inserted A layered hose, wherein the inner layer is formed in the center of the outer layer and on the inner peripheral surface of the end into which the mating member is inserted, and the thickness of the inner layer portion of the inner peripheral surface of the end into which the mating member is inserted. Is thinner than the thickness of the portion formed on the inner peripheral surface of the central portion of the hose. 3. A multi-layer structure comprising an outer layer made of rubber and an inner layer integrally made of resin or metal on the inner peripheral surface of the outer layer, and a mating nipple is inserted inside the end to be connected. A multi-layer hose, wherein the inner layer is formed on an inner peripheral surface of a central portion of the outer layer and a part of an inner peripheral surface of the end portion into which the mating member is inserted from the central portion. .