JP2004052811A - End fastening structure of hose with bellows type metal pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily fix and seal an insert pipe and a bellows type metal pipe by simply crimping socket metal fittings without welding when fixing an end of a hose body with a bellows type metal pipe by crimping of the socket metal fittings. <P>SOLUTION: An axial pointed end of the bellows type metal pipe 18 is exposed from outer layers 20, 22, and 24 of a hose 10 with a bellows type metal pipe, and is extended from a base 32 of the socket metal fittings to an axial direction. The hose body 12, the insert pipe 14, and the socket metal fittings 16 are integrally fixed so that an extended portion 30 is pushed between an inner end face of the base 32 and an outer surface of the insert pipe 14 by crimping the socket metal fittings. A contact faces between the bellows type metal pipe 18 and insert pipe 14 are airtightly sealed. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hose with a bellows metal tube suitable as a hose for transporting fuel for automobiles and a hose for transporting refrigerants and other fluids, and particularly to a fastening structure at an end.
[0002]
[Prior art]
Conventionally, a general rubber hose having good vibration absorption and assembling properties, such as NBR / PVC (a blend of acrylonitrile butadiene rubber and polyvinyl chloride), which has excellent gasoline permeability, has been used for fuel transportation of automobiles. However, regulations on permeation of fuel for automobiles are strict from the viewpoint of global environmental protection, and it is expected that the regulations will be further strengthened in the future. It is necessary to cope with a fluid having high permeability, and it is expected that it will be difficult to satisfy the required performance with a hose made of only an organic material such as rubber or resin.
[0003]
Therefore, as a form of a low permeability hose in the future, use of a hose having a bellows metal tube in the inner layer, which can be expected to have a very high fluid impermeability, is being studied.
[0004]
2. Description of the Related Art Conventionally, as this type with a bellows metal tube, those disclosed in the following literatures 1, 2 and 3 are known.
[Document 1] JP 2001-182872 [Document 2] JP 2001-341230 [Document 3] Japanese Utility Model Application Publication No. 51-150511
In the case of a hose with a bellows metal tube, even when hydrogen gas having a small molecular weight used in a fuel cell is used, the gas permeation can be made zero by the bellows metal tube of the inner layer, that is, gas permeation can be completely prevented. It is.
However, in the case of a hose with a bellows metal tube, since the inner layer of the bellows metal tube has a high rigidity, a fastening structure of the end portion ensuring the sealing performance becomes a problem.
[0006]
Conventionally, for a hose end, as shown in FIG. 6, a rigid metal insert pipe 202 is inserted into a hose main body 200, and a socket fitting 204 provided with an inward flange base 206 is externally fitted. Then, the hose body 200, the insert pipe 202 and the socket fitting 204 are integrally fastened and fixed by caulking the socket fitting 204 inward in the radial direction, and a seal is formed between the inner surface of the hose body 200 and the insert pipe 202. I am trying to do it.
[0007]
However, in the case of a hose having a bellows metal pipe in the inner layer, it is difficult to obtain sufficient adhesion between the bellows metal pipe and the insert pipe. It leaks out easily. For this reason, in the case of such a hose with a bellows metal tube, the end of the bellows metal tube is welded to the insert pipe to secure the sealing property.
[0008]
[Problems to be solved by the invention]
However, such welding work for sealing the end of the hose is extremely difficult and not only increases the manufacturing cost of the hose, but also reduces the strength of the insert pipe 202 and the bellows metal tube due to the heat effect during welding. It can be a factor that impairs quality reliability.
In the above, the description has been made by taking the example of the hydrogen gas transport hose used in the fuel cell. However, the same problem is caused by having a bellows metal tube for transporting a small molecular weight refrigerant such as CO _{2 having} high gas permeability and other fluids. This is a common problem in the case where a hose is used, or in the field of hoses with strict permeation regulations such as hoses for transporting automobile fuel.
[0009]
[Means for Solving the Problems]
The end fastening structure of the hose with a bellows metal tube of the present invention has been devised to solve such a problem.
According to the first aspect of the present invention, a hose body having a bellows metal tube as an inner layer and an outer layer including an elastic layer laminated on the radially outer side thereof has a rigid body inside the hose body at an axial end. While inserting the insert pipe, a socket is externally fitted to the outer surface of the hose body and the socket is caulked radially inward, and the end of the hose body, the insert pipe and the socket are integrally fastened and fixed. An end fastening structure for a hose with a bellows metal tube, comprising: an end portion in the axial direction of the bellows metal tube, which is exposed from the outer layer and extends, and the extending portion faces at least inward in the socket fitting. It is characterized in that it extends to a position reaching the tip of the flange-shaped base.
[0010]
According to a second aspect of the present invention, in the first aspect, the extending portion of the bellows metal tube has a non-bellowing shape and a substantially straight shape in the axial direction, and the extending portion faces inward in the socket fitting. It is characterized by extending beyond the flange-shaped base to the outside in the axial direction.
[0011]
According to a third aspect of the present invention, in the state according to any one of the first and second aspects, the extending portion is clamped between an inner end surface of the base and an outer surface of the insert pipe in the socket by caulking the socket. The hose body, the insert pipe and the socket fitting are integrally fastened and fixed, and the space between the bellows metal pipe and the insert pipe is hermetically sealed.
[0012]
According to a fourth aspect of the present invention, in any one of the first to third aspects, a radial groove is provided on one of an outer surface of the insert pipe and an inner end surface of a base portion of the socket fitting, and a fitting portion into the groove is provided on the other. And the extension portion is sandwiched between the groove and the fitting portion.
[0013]
According to a fifth aspect of the present invention, in the fourth aspect, the fitting portion is provided by plastic deformation by the groove at the time of caulking the socket fitting, and the fitting portion is provided to the groove via the extending portion. It is characterized in that the extension portion is pressed by the fitting portion, the bottom surface of the groove, and the side surfaces of the groove before and after in the axial direction.
[0014]
According to a sixth aspect of the present invention, in the fifth aspect, the groove is formed on an outer surface of the insert pipe, and the fitting portion is formed by plastic deformation at the time of the caulking. The thickness of the inner end portion in the direction is set to be larger than a dimension obtained by subtracting at least twice the thickness of the extending portion from the groove width of the groove before the caulking.
[0015]
According to a seventh aspect of the present invention, in any one of the first to sixth aspects, a small radial protrusion is provided on one of an outer surface of the insert pipe and an inner end surface of a base portion of the socket fitting for clamping the extending portion, and the other. A small concave portion is formed by plastic deformation by the small projection at the time of the caulking, and the extending portion is sandwiched between the small projection and the small concave portion.
[0016]
[Action and effect of the invention]
As described above, according to the present invention, the axial distal end of the bellows metal tube is exposed and extended from the radially outer layer, and the extended portion is formed at least at the distal end of the inward flange base of the socket fitting. When the socket is caulked inward in the radial direction, the bellows metal tube is formed between the inner end surface of the base of the socket and the outer surface of the insert pipe. Can be pinched.
[0017]
Here, the extending portion of the bellows metal tube has a non-bellows shape and a substantially straight shape in the axial direction, which can extend beyond the base of the socket fitting to the outside in the axial direction. 2).
By doing so, it is possible to more reliably and firmly clamp the extension between the base of the socket fitting and the insert pipe.
[0018]
When the extension is pressed between the inner end face of the base of the socket fitting and the outer face of the insert pipe (claim 3), the hose body, the insert pipe and the socket fitting are fastened and fixed. The airtight seal between the bellows metal pipe and the insert pipe can be made, and the hose end can be easily fixed and sealed simply by caulking the socket fitting without welding work as in the past. And can be done.
[0019]
Therefore, according to the present invention, it is possible to manufacture the hose including fixing and sealing at the end of the hose at low cost, and it is possible to prevent a decrease in the strength of the insert pipe or the bellows metal tube accompanying the welding joining of the bellows metal tube, Quality reliability at the end of the hose can be improved.
[0020]
According to a fourth aspect of the present invention, one of the outer surface of the insert pipe and the inner end surface of the base of the socket fitting is provided with a radial groove, and the other is provided with a fitting portion into the groove. The holding force can be further increased, and the sealing performance can be improved at the same time.
[0021]
In this case, the fitting portion is formed by plastic deformation by the groove at the time of caulking of the socket fitting, whereby the fitting portion and the groove are engaged with each other (via the extension portion), whereby the extension portion is connected to the fitting portion. It can be fixed and sealed by being sandwiched between the groove and the groove bottom surface and the groove side surfaces before and after in the axial direction.
In this case, the fixing force and the sealing performance can be more effectively improved.
[0022]
In the fifth aspect, the groove is formed on the outer surface of the insert pipe, and the thickness of the inner end portion of the base of the socket fitting is obtained by subtracting twice the thickness of the extending portion from the groove width before caulking. It can be larger than the dimensions (claim 6).
By doing so, the inner end of the base of the socket fitting can be securely fitted into the groove with plastic deformation during caulking.
[0023]
Further, when the fitting portion is formed by plastic deformation at the time of caulking, the hardness on the side where the fitting portion is formed can be made lower than the hardness on the groove side.
[0024]
In the present invention, a small projection is formed on one of the outer surface of the insert pipe and the inner end surface of the base of the socket fitting, and a small recess is formed on the other side by plastic deformation by the small projection, regardless of whether the groove is formed. The extension can be sandwiched between the small projection and the small recess (claim 7).
Even in such a case, the sealing performance can be effectively improved.
[0025]
In this case, it is desirable that the height of the small projection is lower than the thickness of the extension.
If the height of the small projection is set to be higher than the thickness of the extension, the extension may be cut by the small projection during caulking. By lowering this, such a problem can be avoided.
[0026]
【Example】
Next, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, reference numeral 10 denotes a hose with a bellows metal tube (hereinafter simply referred to as a hose) suitable as a hydrogen transport hose, an automobile fuel hose, or a refrigerant transport hose for an air conditioner. A metal rigid insert pipe 16 inserted into the inside of the hose body 16 is a socket fitting externally fitted to the hose body 12. By caulking the socket fitting 16, the end of the hose body 12 is inserted into the insert pipe 14 and the socket fitting. 16 are integrally fastened and fixed and sealed.
FIG. 2 specifically shows a fixing and sealing structure of the end of the hose 10.
[0027]
As shown in FIG. 2, the hose body 12 has a bellows metal tube 18 made of a stainless steel tube or the like on the innermost layer, and an inner elastic layer 20, a reinforcing layer 22, and an outer elastic layer 24 are laminated on the outer side thereof. Are integrally fixed by vulcanization bonding or the like. Here, the inner elastic layer 20, the reinforcing layer 22, and the outer elastic layer 24 constitute an outer layer outside the bellows metal tube 18.
Here, the reinforcing layer 22 may be a wire reinforcing layer or a fiber reinforcing layer.
The inner elastic layer 20 can be made of rubber or resin having elasticity. Further, the outer elastic layer 24 can be a rubber layer.
[0028]
On the other hand, the bellows metal tube 18 of the innermost layer has a bellows portion 26 almost entirely in the longitudinal direction, and the bellows portion 26 imparts flexibility.
That is, although the hose 10 of this example has the bellows portion 26 provided on the metal tube even though the innermost layer is formed of the metal tube, flexibility is imparted as a whole.
[0029]
This bellows metal tube 18 has a non-bellows-shaped and axially straight portion 28, and a part of the tip side is exposed from an outer layer composed of the inner elastic layer 20, the reinforcing layer 22, and the outer elastic layer 24. The extension portion 30 extends.
Here, the extension portion 30 extends beyond the distal end position of the inward flange base 32 of the socket fitting 16 to the outside in the axial direction.
The extending portion 30 is sandwiched between the outer surface of the insert pipe 14 and the base 32 of the socket fitting 16, and the bellows metal tube 18 is fixed to the insert pipe 14 and the socket fitting 16.
[0030]
In this example, the fixing structure is as follows.
That is, in this example, a radial groove 34 is formed at a position corresponding to the base 32 of the socket fitting 16 on the outer surface of the insert pipe 14, and as shown in the partially enlarged view of FIG. The fitting portion 36 on the base 32 side is fitted, and the extension portion 30 deformed along the shape of the groove 34 is pressed by the groove 34 and the fitting portion 36 between the bottom surface of the groove and a pair of groove side surfaces in the front-rear direction. The extension portion 30 is fixed to the insert pipe 14, and at the same time, the space between the bellows metal tube 18 and the insert pipe 14 is hermetically sealed at the fixing portion.
[0031]
Here, the fitting portion 36 meshes with the groove 34 via the extension portion 30, and the extension portion 30 is firmly fixed based on the engagement, and at the same time, the sealing at the fixed portion is favorably performed. Is being done.
Here, the fitting portion 36 is formed by plastically deforming the socket fitting 16 into a shape corresponding to the groove 34 at the time of caulking the socket fitting 16 inward in the radial direction.
[0032]
Specifically, the inner end portion of the base portion 32 of the socket member 16 as shown in FIG. 2 (A) is the wall thickness of the W _1.
The wall thickness W ₁ is the major dimension than the value obtained by subtracting twice the thickness t of the extending portion 30 from the groove width W ₂ of the groove 34.
When the socket bracket 16 is crimped inward in the radial direction, the inner end of the base portion 32 is plastically deformed while deforming the extension portion 30 along the shape of the groove 34 (the hardness of the base portion 32 is determined by an insert. (The hardness is lower than that of the pipe 14) to form the fitting portion 36.
Therefore, the fitting portion 36 is engaged with the groove 34 via the extending portion 30 (see FIG. 2B).
[0033]
Then, the fitting portion 36 is in a state in which the extension portion 30 is strongly pressed together with the groove 34 on the groove bottom surface and the groove side surface in the front-rear direction, and the extension portion 30, that is, the end of the bellows metal tube 18 is At the same time as fixing, airtightly seal between them.
[0034]
It should be noted that the inner elastic layer 20, the reinforcing layer 22, and the outer elastic layer 24, which are the outer layers, together with the bellows metal tube 18, are naturally firmly fixed to the insert pipe 14 by caulking the socket fitting 16. That is, the end of the hose body 12 is firmly fixed to the insert pipe 14 and the socket fitting 16.
[0035]
In order to improve the adhesion and sealing between the bellows metal tube 18 and the insert pipe 14, it is bonded to one or both of the outer surface of the insert pipe 14 and the inner surface of the straight portion 28 of the bellows metal tube 18. The outer surface of the insert pipe 14 and the inner surface of the straight portion 28 are formed by applying a coating agent and bonding them together, or by interposing a coating agent, a thin-walled elastomer or the like between the both surfaces thereof. You may make it match.
[0036]
In addition, when a similar coating agent, a thin elastomer, or the like is interposed on the outer surface of the straight portion 28 (particularly, the engagement surface with the base 32 of the socket fitting 16), if the surface of the straight portion 28 is damaged, By filling the wound, the sealing property can be improved. Note that the thin portion on the outer surface of the straight portion 28 leaves a part of the radially outer side of the bellows metal tube 18 from the end of the integrally formed hose 10 including the elastic layer on the radially outer side of the metal bellows tube 18. The elastic layer may be formed so as to be removed.
[0037]
According to the fastening structure of the present embodiment, the end of the hose 10 can be easily fixed and sealed simply by caulking the socket fitting 16 without performing welding or the like between the bellows metal tube 18 and the insert pipe 14. be able to.
In addition, since it is not necessary to weld the bellows metal pipe 18, it is possible to prevent a decrease in the strength of the insert pipe 14 or the bellows metal pipe 18 due to the welding, and to improve the quality reliability at the end of the hose 10.
[0038]
In this example, a radial groove 34 is provided on the outer surface of the insert pipe 14, and the inner end face of the base 32 of the socket 16 is plastically deformed by the groove 34 to form the fitting portion 36 when the socket 16 is crimped. Since the extension portion 30 is pressed by engaging the fitting portion 36 with the groove 34, the fixing force at the end of the hose 10 can be increased, and the sealing property can be improved at the same time.
[0039]
In the above embodiment, both the side surface of the groove 34 and the front and rear surfaces of the base 32 are perpendicular to the axis of the hose 10, but as shown in FIG. , The rear surface may be a tapered surface, or a pair of groove side surfaces before and after the groove 34 may be tapered as shown in (B), or the groove side surface and the base portion as shown in (C). Both the front and rear surfaces of 32 can be tapered surfaces.
In this case, the radially inner end of the base 32 can be favorably plastically deformed by the groove 34 when the socket fitting 16 is swaged.
[0040]
FIG. 4A shows still another embodiment of the present invention. Here, a small projection 38 is provided on the bottom surface of the groove 34, and when the socket fitting 16 is crimped, the small projection 38 allows the base portion to be formed. A corresponding small recess 40 is formed by plastic deformation on the inner end face of the base 32, and the extension 30 is formed in the radial direction by the bottom face of the groove 34 including the small projections 38 and the small recess 40 and the inner end face of the base 32. This is an example in which clamping and fixing are performed to form a seal. The extension 30 is similar to the above embodiment in that the extension 30 is deformed along the groove 34 at the time of caulking, and is pressed between the insert pipe 14 and the base 32 in the deformed state.
[0041]
Here, the small protrusion 38 is formed at a height h lower than the thickness t of the extension portion 30.
If the height h of the small projections 38 is set to be higher than the thickness t of the extension portions 30, when the extension portions 30 are sandwiched between the small projections 38 and the small recess portions 40 during crimping, plastic deformation will occur. Although there is a possibility that the extension portion 30 may be cut, such a problem can be avoided by reducing the height h of the small protrusion 38 as shown in the figure.
[0042]
In this example, the inner end of the base 32 does not necessarily need to be plastically deformed at the time of caulking the socket fitting 16 along the groove 34, but the thickness of the inner end of the base 32 may be reduced depending on the case. A dimension larger than a value obtained by subtracting twice the thickness t of the extension part 30 from the groove width of the groove 34 is set, and the inner end of the base 32 is moved along the groove 34 at the time of caulking. You may make it plastically deform.
In this case, the extended portion 30 is also sandwiched between the groove 34 and the base 32 on the pair of front and rear groove side surfaces.
[0043]
Note that, in the example of FIG. 4A, the hardness of the socket fitting 16 is lower than the hardness of the insert pipe 14 having the groove 34 and the small protrusion 38, which is the same as the above embodiment.
[0044]
On the other hand, the example of FIG. 4B is an example in which the small protrusion 38 is provided on the base 32 side and the small recess 40 is provided on the groove 34 side. In this case, the hardness of the insert pipe 14 is lower than the hardness of the socket fitting 16.
In the example of FIG. 4B, the same effect as in the example of FIG. 4A can be obtained.
[0045]
In each of the above examples, a groove 34 is provided on the insert pipe 14 side, and inside the groove 34, the insert pipe 14 and the base 32 of the socket metal fitting 16 radially press the extension 30 of the bellows metal pipe 18. In this case, as shown in FIG. 5, without forming such a groove in the insert pipe 14, the extending portion 30 is simply formed by the outer surface of the insert pipe 14 and the inner end surface of the base 32 in the radial direction. It is also possible to fix and seal the end portion of the bellows metal tube 18.
[0046]
Alternatively, in some cases, a groove is provided on the side of the base 32, while a fitting portion is provided on the side of the insert pipe 14, thereby squeezing the extension 30 in the radial direction, and fixing the end of the bellows metal tube 18. It is also possible to fix the end of the hose body 12 and make a seal between the bellows metal tube 18 and the insert pipe 14.
[0047]
Although the embodiments of the present invention have been described in detail above, these are merely examples of the present invention, and the present invention can be applied for transporting various fluids, and various modifications are made without departing from the gist of the present invention. Can be configured.
[Brief description of the drawings]
FIG. 1 is a view showing a hose with a bellows metal tube according to an embodiment of the present invention.
FIG. 2 is a diagram showing a fastening and fixing and sealing structure of an end of a hose in FIG. 1;
FIG. 3 is a diagram showing a main part of another embodiment of the present invention.
FIG. 4 is a diagram showing a main part of still another embodiment of the present invention.
FIG. 5 is a diagram showing a main part of still another embodiment of the present invention.
FIG. 6 is an explanatory diagram for explaining the background of the present invention.
[Explanation of symbols]
Reference Signs List 10 Hose with bellows metal tube 12 Hose body 14 Insert pipe 16 Socket fitting 18 Bellows metal tube 20 Inner elastic layer (outer layer)
22 Reinforcement layer (outer layer)
24 outer elastic layer (outer layer)
28 Straight portion 30 Extension portion 32 Base portion 34 Groove 36 Fitting portion 38 Small protrusion 40 Small recess W ₁ Thickness W ₂ Groove width t Thickness

Claims (7)

A rigid insert pipe is inserted into the hose body at an axial end thereof with respect to a hose body having a bellows metal tube in an inner layer and an outer layer including an elastic layer laminated radially outward, while the hose body is A socket fitting is externally fitted to the outer surface of the hose, and the socket fitting is crimped inward in the radial direction, and an end of the hose body, an end pipe, and an end portion of a hose with a bellows metal pipe formed by integrally fastening and fixing the insert pipe and the socket fitting. A fastening structure,
The tip of the bellows metal tube in the axial direction is exposed from the outer layer and extended, and the extended portion is extended to at least a position reaching the tip of the inward flange base of the socket fitting. The end fastening structure of a hose with a bellows metal tube. 3. The bellows metal tube according to claim 1, wherein the extension of the bellows metal tube has a non-bellows shape and a substantially axial straight shape, and the extension extends beyond an inward flange base of the socket fitting. An end fastening structure for a hose with a bellows metal tube, which extends to the outside in the axial direction. The hose body, the insert pipe and the insert pipe according to any one of claims 1 and 2, wherein the extension is pressed by an inner end surface of the base and an outer surface of the insert pipe in the socket by caulking the socket. An end fastening structure for a hose with a bellows metal tube, wherein the socket fitting is integrally fastened and fixed, and the space between the bellows metal tube and the insert pipe is hermetically sealed. 4. The extending portion according to claim 1, wherein a radial groove is provided on one of an outer surface of the insert pipe and an inner end surface of a base of the socket fitting, and a fitting portion is provided in the other groove, and the extending portion is provided. The end fastening structure of a hose with a bellows metal tube, characterized in that the pressure is clamped between the groove and the fitting portion. 5. The fitting according to claim 4, wherein the fitting portion is provided by plastic deformation by the groove at the time of caulking the socket fitting, and the fitting portion is engaged with the groove via the extension portion. Characterized in that the pressure is clamped between the fitting portion and the bottom surface of the groove and the side surfaces of the groove in the axial direction. In claim 5, wherein the groove is formed on the outer surface of the insert pipe, and the fitting portion is formed by plastic deformation at the time of the caulking. An end fastening structure of a hose with a bellows metal pipe, wherein the dimension is at least larger than a width obtained by subtracting twice the thickness of the extension from the groove width of the groove in a state before caulking. . A small radial projection on one of the outer surface of the insert pipe and the inner end surface of the base of the socket fitting, which presses the extension, according to any one of claims 1 to 6, wherein the caulking is performed on the other. An end fastening structure for a hose with a bellows metal tube, wherein a small recess is formed by plastic deformation by the small projection, and the extension is sandwiched between the small projection and the small recess.

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