JPH08277972A - Bellows hose - Google Patents

Abstract

PURPOSE: To locally increase a bending property in a bellows part and to facilitate installation of a bellows hose between counter-members while maintaining negative pressure resistance and pull-out resistance in the bellows hose. CONSTITUTION: A bellows hose extending from one end to the other end along an axial line is provided with connection end parts 11, 12, which can be connected between counter-members, and in the intermediate cylindrical part 10a between the connection end parts 11, 12, a bellows part 13, in which a plurality of crest-shaped ring type projection parts 14a, 14b, 14c and the like are continuously formed, is arranged. At least one side of bellows ends 13a, 13b, an inclination of the first slanting part. 14a1, which is formed on the bellows part center side of the first projection part 14a from the bellows end 13a, to the axial line is set to be smaller than that of the second slanting part 14a2 formed on the bellows end side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bellows hose having excellent stretchability, negative pressure resistance and burst resistance, and more particularly to improvement thereof.

[0002]

2. Description of the Related Art Heretofore, a bellows hose of this type has a mountain-shaped ring shape extending from one end to the other end along an axis and projecting in a direction perpendicular to the axis in at least a part of an intermediate tubular portion excluding a connecting portion at both ends. The protrusion has a bellows portion in which a plurality of protrusions are continuously arranged in the axial direction, and the inclinations of the inclined portions on both sides of the mountain shape of the ring-shaped protrusions forming the bellows portion are made equal and large with respect to the axis. Was there. As a result, the bellows hose has excellent stretchability and excellent withdrawal characteristics that it is difficult for the bellows hose to come off from a mating member such as a pipe connected by extension deformation. Further, in this bellows hose, since the ring-shaped convex portion acts as the radial thickness of the hose, negative pressure resistance that suppresses deformation when the inside of the hose becomes low pressure, and when the inside of the hose becomes high pressure, It was also equipped with burst resistance to prevent deformation.

[0003]

However, in the bellows hose described above, when connecting between two mating members 2a and 2b arranged obliquely as shown in FIG. As shown in FIGS. 6 (b) and 6 (c), the straight bellows hose 1 is bent, but the distance between the mating members 2a and 2b is short, and the ring-shaped protrusion has a uniform and large inclination. Therefore, it is difficult to locally bend the ring-shaped convex portions contacting each other, and therefore it is very complicated to attach both end connecting portions of the bellows hose 1 to the mating members 2a and 2b. To facilitate this installation,
The inclination of both sides of the apex of the ring-shaped convex part with respect to the axis may be reduced, but this reduces the stretchability of the bellows hose and makes it easier for the bellows hose to come off from the mating member when a pulling force acts on the bellows hose. There is a problem.
Further, the negative pressure resistance and burst resistance of the bellows hose are also impaired.
The present invention is intended to solve the above-mentioned problems, and provides a bellows hose capable of enhancing the local bendability of the bellows portion while suppressing deterioration of the withdrawal characteristics, negative pressure property and bursting property of the bellows hose. The purpose is to do.

[0004]

In order to achieve the above object, the structural feature of the invention according to claim 1 is that it has an intermediate tubular shape extending from one end to the other end along an axis and excluding a connecting portion at both ends. At least one of both bellows ends of the bellows portion, in a bellows hose having a bellows portion in which a plurality of mountain-shaped ring-shaped projections projecting in a direction perpendicular to the axis are provided in at least a part of the portion in a continuous manner in the axial direction. With respect to at least one ring-shaped convex portion from the bellows end, the inclination of the first inclined portion formed on the center side of the bellows portion with respect to the axis with respect to the top of the ring-shaped convex portion is defined as The inclination is smaller than the inclination of the second inclined portion formed on the axis.

Further, the structural feature of the invention according to claim 2 is that it extends along the axis from one end to the other end and projects in the direction perpendicular to the axis to at least a part of the intermediate tubular portion excluding the connecting portions at both ends. In a bellows hose having a bellows portion in which a plurality of mountain-shaped ring-shaped convex portions are continuously arranged in the axial direction, in at least one of both bellows ends of the bellows portion, a center of the bellows portion from the bellows end. The inclination of the first inclined portion formed on the center side of the bellows portion with respect to the apex of the ring-shaped convex portion arranged toward the axis is gradually increased as each ring-shaped convex portion is closer to the center. At the same time, the pitch between the ring-shaped convex portions is gradually reduced toward the center.

Further, the structural feature of the invention according to claim 3 is that in the bellows hose according to claim 1 or 2, the intermediate tubular portion is made of a resin material and is substantially single-phase. Is being done.

Further, the constitutional feature of the invention according to claim 4 is that, in the bellows hose according to claim 1 or 2, a resin layer in which the intermediate tubular portion is arranged as an inner surface layer, and an outer surface. And a rubber layer arranged as a layer.

Further, the structural feature of the invention according to claim 5 is that in the bellows hose according to claim 4, the resin layer and / or the rubber layer has a two-layer structure.

[0009]

In the invention according to claim 1 configured as described above, the inclination of the first inclined portion formed on the center side of the bellows portion with respect to the apex of the ring-shaped convex portion with respect to the axis is set. Since it is made smaller than the inclination of the second inclined portion on the bellows end side with respect to the axis, between the mating members fixedly arranged,
When connecting both end connecting portions of such a bellows hose, when the bellows hose is bent at least from the bellows end in the vicinity of the first ring-shaped convex portion to a desired bend radius that can be connected, the first inclination is inside the bend radius. While the part can be deformed to cover the adjacent ring-shaped convex part, outside the bending radius, the second part
The inclined portion can promote the extension on the outer peripheral side, and locally bend easily near the first ring-shaped convex portion. Since the second inclined portion has a large angle with respect to the axis, it acts as an effect of the rib, and the negative pressure resistance of the bellows hose can be enhanced.

As a result, the workability of mounting the bellows hose on the mating member is improved. With respect to the pull-out characteristic of the bellows hose, the pull-out characteristic is hardly impaired because the elasticity of the other ring-shaped convex portion having a large inclination with respect to the axis of the inclined portions on both sides mainly contributes. Further, the negative pressure resistance and the burst resistance of the bellows hose are not deteriorated in the same manner as the pull-out characteristics. Also, due to the increased flexibility of the bellows hose, the bellows hose can be made of resin or a highly rigid material having a composite structure such as resin-rubber, which allows the bellows hose to have negative pressure resistance and burst resistance. The sex can be further enhanced.

Further, in the invention according to claim 2 configured as described above, the ring-shaped projections arranged from the bellows end toward the center of the bellows are formed on the center side of the bellows with the tops as boundaries. The flexibility of the bellows hose is further enhanced by gradually increasing the inclination of the first inclined portion with respect to the axis line as the ring-shaped convex portions are closer to the center. Further, it is possible to suppress the pulling-out property of the bellows hose, and the deterioration of negative pressure property and burst property.

In the invention according to claim 3 configured as described above, when the cylindrical intermediate portion is molded by blow molding or the like, it is possible to mold in various states from hard to soft. As a result, in addition to the effects of the invention according to claim 1 or claim 2, a tubular intermediate portion having various properties can be obtained.

In the invention according to claim 4 configured as described above, the outer surface side is softened by the rubber layer,
Fuel permeation resistance can be obtained by making the inner surface layer a thin resin layer. As a result, in addition to the effects of the invention according to claim 1 or claim 2, the bellows hose can be preferably used as a fuel hose.

In addition, in the invention according to claim 5 configured as described above, in addition to the effect of the invention according to claim 4, it is possible to obtain an intermediate cylindrical portion having various hardness from soft to hard. it can.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a partial sectional view of a bellows hose 10 arranged between a fuel tank and a filler pine of an automobile according to the first embodiment. It is shown schematically in the figure. Bellows hose 1
0 is made of a resin such as nylon, extends from one end to the other along the axis and has a symmetrical shape in the axial direction, and has connecting ends 11 and 12 into which mating members are inserted at both ends, and an intermediate portion between them. A bellows portion 13 is provided on the tubular portion 10a. The bellows portion 13 is a ring-shaped convex portion 1 having a mountain-shaped cross section perpendicular to the axial direction.
4 are arranged in succession. Of the protrusions 14, the first protrusion 14a from the one bellows end 13a is the top 14
The first inclined portion 14 on the center side of the bellows portion 13 with a3 as a boundary
The second inclined portion 1 formed on the side of the bellows end 13a has an inclination (hereinafter, simply referred to as inclination) of a1 with respect to the axis of about 30 °.
The inclination of 4a2 is about 60 °, and the second inclined portion 14a2
The slope is much smaller. In the second convex portion 14b from both ends, the inclination of the first inclined portion 14b1 on the center side is about 45 °, which is larger than the inclination of the first convex portion 14a, and the second inclined portion on the side of the bellows end 13a. The inclination of the inclined portion 14b2 is about 80 °. Further, from the third convex portion 14c from both ends, the inclination of the first inclined portion 14c1 on the center side and the inclination of the second inclined portion 14c2 on the bellows end 13a side are about 8
It is the same at 0 °. The above also applies to the convex portions 14d, 14e, 14f, etc. on the bellows end 13b side.

In the first embodiment constructed as described above, when the bellows hose 10 is bent from the bellows end 13a in the vicinity of the first convex portion 14a, the first portion on the center side of the convex portions 14a and 14b is formed. Since the inclinations of the inclined portions 14a1 and 14b1 are small, the rotatable range of the next convex portions 14b and 14c is increased. Therefore, the flexibility of the bellows hose 10 near the convex portion 14a is enhanced. This means that the bellows end 13b
The same applies to the first convex portion 14d on the side. When connecting both end connecting portions 11 and 12 of the bellows hose 10 to a mating member that is not on the same line, at least the bellows end 1
First ring-shaped protrusions 14a and 14d from 3a and 13b
When the bellows hose 10 is bent in the vicinity so as to have a connectable desired bending radius, the first inclined portion 14a is formed inside the bending radius.
While 1 and 14d1 can be deformed so as to cover the adjacent ring-shaped convex portions 14b and 14e, outside the bending radius, the second inclined portions 14a2 and 14d2 can promote the extension on the outer peripheral side and the first ring-shaped portion. It becomes easy to bend locally near the protrusions 14a and 14d. Therefore, the workability of attaching the bellows hose 10 to the mating member is improved.

As for the withdrawal characteristic of the bellows hose 10 from the counterpart member, the withdrawal characteristic is mainly due to the stretchability of the bellows part on the center side from the convex portions 14c and 14f having large inclinations on both sides. It is hardly damaged. Further, regarding the negative pressure resistance and the burst resistance of the bellows hose 10, the slopes of the slopes on both sides of the projections on the center side of the bellows from the projections 14c and 14f are increased, and the bellows end 1
Convex portions 14a, 14b, 14d, 1 near 3a, 13b
For 4e, the second inclined portions 14a2, 14b2, 14
Since the inclination of d2 and 14e2 with respect to the axis is large, this portion acts as a rib effect. Therefore, since these portions can support the stress in the circumferential direction, the negative pressure resistance and the burst resistance of the bellows hose 10 are not deteriorated in the same manner as the pull-out characteristics.

Next, a first modification of the first embodiment will be described with reference to FIG. In the modified example 1, the inclination of the first inclined portions 14a1 and 14b1 with respect to the first convex portion 14a and the second convex portion 14b from the bellows end 13a at one end of the bellows portion 13 of the bellows hose 10 toward the center side. Is reduced, and the convex portion 14d on the other end side is inclined on both sides.
The inclinations of 1 and 14d2 are the same as those of the central convex portion. In the modified example 1, in consideration of the case where the bellows hose 10 is bent only on one end side, the inclination of the inclined portion of only a necessary portion is changed. As a result, the required portion of the bellows hose 10 can be easily bent, and the pull-out characteristics, negative pressure resistance, burst resistance, etc. of the bellows hose 10 can be properly secured.

Next, a second embodiment will be described with reference to the drawings. The bellows hose 20 according to the second embodiment extends along the axis from one end to the other end in the axial direction, and as shown in FIG. 3, the two bellows parts of the intermediate tubular part 20a between the connecting parts 21 and 22 at both ends. 23 and 24 are integrally connected via a straight portion 26. Both the bellows portions 23 and 24 have the same structure as the bellows portion 13 shown in the first embodiment. The bellows hose 20 configured as described above has the straight portion 2
6 is preferably used when it is fixed midway, and regarding the bent portion, both ends of the bellows portions 23 and 24 are configured as shown in the first embodiment to obtain the same effect. You can In addition, the portion that does not need to be bent has a straight shape so that the bellows hose can be manufactured easily and inexpensively.

Next, a second modification of the second embodiment will be described with reference to FIG. In the second modification, both bellows parts 2
For each of the two convex portions 25a and 25b at the end portions connected to both end connecting portions 21 and 22 of 3, 24, the first inclined portion 25a1,
The inclination of 25b1 is reduced and the inclinations of the inclined portions 25c1, 25c2, 25d1 and 25d2 on both sides of the protrusions 25c and 25d on the other end side, which are integrally connected to the straight portion 26, are made the same as those of the central portion. It is a thing. This bellows hose 20 has the tilt of the inclined portion changed only in a necessary portion in consideration of the case where the bellows portion is bent only on one end side. As a result, the required portion of the bellows hose 20 can be easily bent, and the pull-out characteristics, negative pressure resistance, burst resistance, etc. of the bellows hose 20 can be properly secured. In the second modification, the slope of one of the protrusions 25c and 25d may be adjusted to the slope of the slope of the protrusions 25a and 25b. Further, although the straight portion 26 has a straight shape in the second embodiment and the second modification, it may have a curved shape.

Next, a third embodiment will be described with reference to the drawings. As shown in FIG. 5, the bellows hose 30 according to the third embodiment has a right side connecting portion 32 among the connecting portions 31 and 32 at both ends.
The bellows portion 33 is connected only to the end portion, and the bent straight portion 34 is integrally connected between the connection portion 31 and the other end of the bellows portion 33. The bellows portion 33 has the same structure as the bellows portion 13 shown in the first embodiment.

The bellows hose 30 constructed as described above is
The distance between the mating members to be connected is long and the bellows hose 30
It is suitable for use when one bent can be covered with a single bellows. With regard to the bent portion, the same effect can be obtained by constructing both ends of the bellows portion 33 as shown in the first embodiment. Further, by forming the straight portion 34 in a required bent shape in advance, the bellows hose can be manufactured easily and inexpensively. Also in the third embodiment, the convex portion 33a on the side of the connecting portion of the bellows portion 33 with the straight portion 34,
With respect to 33b, the inclination of the inclined portions on both sides can be made the same as that of the convex portion in the intermediate portion. In addition, in the third embodiment, the bent straight portion 34 may be formed in a straight shape if necessary.

Next, a fourth embodiment will be described. In the fourth embodiment, regarding the shape of the convex portion of the bellows portion of the bellows hose in each of the above-mentioned embodiments and modifications, the inclination of the convex portion on the central side of the bellows is changed from the convex portion on the bellows end side to the convex portion on the central portion of the bellows portion. It is configured such that it gradually increases toward the portion (the shape is not shown). In the bellows hose thus configured, the flexibility of the bellows hose is further enhanced.

In addition, in the first to third embodiments and the respective modifications, the inclination of the central inclined portion of the two convex portions from the bellows end is made small, but the present invention is not limited to this, and one or three. The inclination of the inclined portion on the center side of the one or more convex portions may be reduced. Further, various changes can be made to the number and combination of the bellows portion and the straight portion shown in the second and third embodiments and the modified examples.

Further, in each of the above-mentioned embodiments and modifications, each bellows hose is made of a resin such as nylon, and is made into a substantially single phase by combining a soft material and a hard material by blow molding. However, the inner surface layer is a thin resin layer and the outer surface layer is a rubber layer such as EPDM resin /
It can also be configured as a two-layer rubber product. The inner surface layer may have a two-layer structure of resin, or the outer surface layer may have a two-layer structure of fluororubber and hydrin rubber. Further, rubber, a two-layer rubber / rubber product, and other composite materials can be used. In particular, by increasing the bendability of the bellows hose, it is possible to bend the bellows hose even if a highly rigid material is used, and as a result, the negative pressure resistance and burst resistance of the bellows hose are further enhanced.

It should be noted that the end portions of the bellows hose shown in each of the above embodiments and modifications and the main body portion between them are not made of a single material but different materials such as rubber for the end portion and resin for the main body portion. It is also possible to use various materials in combination. Further, in each of the above-mentioned embodiments and modifications, the bellows hose is used as a fuel hose for automobiles,
Application to other uses is also possible.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view schematically showing a bellows hose according to a first embodiment of the present invention.

FIG. 2 is a partially broken sectional view schematically showing a bellows hose according to a first modification.

FIG. 3 is a partially broken sectional view schematically showing a bellows hose according to a second embodiment.

FIG. 4 is a partially broken sectional view schematically showing a bellows hose according to Modification 2.

FIG. 5 is a partially broken sectional view schematically showing a bellows hose according to a third embodiment.

FIG. 6 is an explanatory view schematically showing a usage state of a bellows hose according to a conventional example.

[Explanation of symbols]

10 ... Bellows hose, 11, 12 ... Connection end portion, 13 ... Bellows portion, 14, 14a, 14b, 14c ... Convex portion, 14a1,
14a2, 14b1, 14b2, 14c1, 14c2,
14d1, 14d2 ... inclined part, 20 ... bellows hose, 2
1, 22 ... Connection end portion, 23, 24 ... Bellows portion, 25a, 2
5b, 25c, 25d ... Convex portions, 25a1, 25b1, 2
5c1, 25c2, 25d1, 25d2 ... Inclined portion, 26
... Straight part, 30 ... Bellows hose, 31, 32 ... Connection end part, 33 ... Bellows part, 33a, 33b ... Convex part, 34 ... Straight part.

Claims (5)

[Claims] 1. A mountain-shaped ring-shaped convex portion extending from one end to the other end along the axis and projecting in a direction perpendicular to the axis on at least a part of the intermediate tubular portion excluding the connection portions at both ends is continuous in the axial direction. In a bellows hose having a plurality of bellows parts, at least one of both bellows ends of the bellows part has at least one ring-shaped projection part from the bellows end, and a top part of the ring-shaped projection part is provided. A bellows hose characterized in that the inclination of the first inclined portion formed on the center side of the bellows portion with respect to the axis is smaller than the inclination of the second inclined portion formed on the bellows end side with respect to the axis. 2. A mountain-shaped ring-shaped convex portion extending from one end to the other end along the axis and projecting in a direction perpendicular to the axis on at least a part of the intermediate tubular portion excluding the connection portions at both ends is continuous in the axial direction. In a bellows hose having a plurality of bellows parts, at least one of both bellows ends of the bellows part of the ring-shaped convex part arranged from the bellows end toward the center of the bellows part. The inclination of the first inclined portion formed on the center side of the bellows portion with respect to the top is gradually increased as each ring-shaped convex portion is closer to the center, and the distance between the ring-shaped convex portions is increased toward the center. A bellows hose whose pitch is gradually reduced. 3. The bellows hose according to claim 1 or 2, wherein the intermediate tubular portion is made of a resin material and has a substantially single-phase structure. 4. The bellows hose according to claim 1 or 2, wherein the intermediate tubular portion includes a resin layer arranged as an inner surface layer and a rubber layer arranged as an outer surface layer. Bellows hose 5. The bellows hose according to claim 4, wherein the resin layer and / or the rubber layer has a two-layer structure.