JP2000304181A - Hose coupling structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform connection only by pressing a hose in a hose connection part and to improve sealing ability even in a vibrating spot. SOLUTION: The coupling structure of a hose is formed that by pressing a hose 30 in a hose connection part, the hose is communicated and connected to a hose connection part 13. The hose connection part 13 is provided on its outer peripheral surface with an annular protrusion part having an outside diameter D1 larger than the inside diameter d1 of the hose and protruding in a mountain range-form state. Provided the length of the hose connection part 13 is Lp and the length of the hose 30 at a part pressed in the hose connection part 13 is Lh, the hose 30 is pressed in the hose connection part 13 such that a press-in ratio defined by Lh/Lp is 1.05-1.4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hose coupling structure for connecting a hose to a hose connection by pressing the hose into the hose connection.

[0002]

2. Description of the Related Art Conventionally, as a hose connecting structure of this type, for example, a technique disclosed in Japanese Patent Application Laid-Open No. 9-159077 is known. FIG. 21 is a partially cutaway front view showing a branch pipe 100 and the like according to a conventional hose coupling structure. In FIG. 21, a hose connection structure is a branch pipe 100 having three branch portions 101, 102, and 103.
And branch hoses 111, 112, and 113 press-fitted into the branch portions 101, 102, and 103, respectively.
On the outer peripheral surface of each of the branch portions 101, 102, 103, ring-shaped protrusions 104, 10 having a mountain-like shape and a triangular cross section are provided.
5 are provided at two intervals. FIG. 22 is an enlarged sectional view showing the vicinity of the branch portion 101. As shown in FIG. 22, the ring-shaped protrusions 104 and 105 have frusto-conical surfaces 104a and 1 whose outer diameter increases from the front end toward the rear end.
05a, and extends from the maximum outer diameter of the truncated cone surfaces 104a, 105a to the general portion of the branch portion 101 and has a truncated cone surface 104.
a, 105a at an acute angle intersecting with the acute angle surface 104b, 10a
5b. On the other hand, the branch hose 111
An inner tube rubber layer 111a made of DM rubber, and a reinforcing thread layer 111 made of yarn and braided or spirally braided;
b and an outer rubber layer 111c made of EPDM rubber.

In such a hose coupling structure, when the branch hose 111 is press-fitted into the branch portion 101, the ring-shaped projections 104 and 105 apply a force for expanding the inner diameter of the branch hose 111. A large reaction force, which prevents expansion by the layer 111b,
Is a force for strongly tightening the branch portion 101. As described above, since the branch hose 111 is prevented from being pulled out by the branch portion 101 with a large force, the branch hose 11 can be removed without using a clamp.
1 can be connected simply by press-fitting it into the branch portion 101.

[0004]

However, in the above-mentioned hose connection structure, since the branch hose 111 is connected by simply press-fitting the branch portion 101 without using a fastener such as a clamp, the size is large. High sealing performance is required as well as retaining force. That is, even when the hose coupling structure is used in a place where the branch hose vibrates relative to the branch part 101 such as an engine room of an automobile or a place where a turning force is applied to the branch hose 111, a high sealing property is obtained. It was required to be maintained.

The present invention solves the above-mentioned problems of the prior art, and can be connected only by press-fitting a hose into a hose connection portion, and has excellent sealing properties even at a vibrating portion. It is an object to provide a hose connection structure.

[0006]

Means for Solving the Problems and Actions and Effects Thereof A first invention for solving the above-mentioned problems is a hose connecting structure in which a hose is press-fitted into a hose connecting portion to be connected to the hose connecting portion. In the body, the hose connection portion has a ring-shaped protrusion formed on the outer peripheral surface thereof, the outer diameter of which is larger than the inner diameter of the hose, and protruding in a mountain range. Assuming that the length of the hose at the portion to be press-fitted into the portion is Lh, the hose is press-fitted into the hose connection portion such that the press-fit ratio defined by Lh / Lp is 1.05 to 1.4.

[0007] A ring-shaped projection is formed in the hose connection portion according to the first invention, and a hose is inserted so as to get over the ring-shaped projection. Since the outer diameter of the ring-shaped projection is formed to be larger than the inner diameter of the hose, the hose generates a large tightening force due to the reaction force to the hose connection part. The hose having such a large tightening force is hard to be pulled out from the hose connection portion and can obtain a large sealing property, and can be securely connected to the hose connection portion without using a fastening means such as a clip. be able to.

Further, when the hose is press-fitted into the hose connection portion, the hose is press-fitted to a portion exceeding the length of the hose connection portion. That is, assuming that the length of the hose connection portion is Lp and the length of the hose at the portion press-fitted into the hose connection portion is Lh, the hose has a press-fit ratio Lh / Lp of 1.05 to 1.
4 is pressed into the hose connection. When the hose is press-fitted into the hose connection portion at such a value of the press-fitting ratio Lh / Lp, the hose expanded by the ring-shaped protrusion can enhance the adhesion to the outer peripheral surface of the hose connection portion, thereby improving the sealing performance.

According to a second aspect of the present invention, in a hose connection structure for connecting a hose to a hose connection by press-fitting the hose into the hose connection, the hose connection has an outer diameter smaller than an inner diameter of the hose on an outer peripheral surface thereof. Is large and has a ring-shaped protrusion protruding in the form of a mountain range, the length of the hose connection portion is Lp, and the length of the hose in the portion press-fitted into the hose connection portion is L.
h, the cross-sectional area of the gap Sp surrounded by the inner wall surface of the hose and the hose connection when the press-fit ratio defined by Lh / Lp is 1, and S0, and the cross-sectional area when the hose is press-fitted into the hose connection Is S1, S1 / S0 is set to 0.95 or less.

Further, in the second invention, as another reference when the hose is press-fitted into the hose connection portion, the length of the hose connection portion is Lp, and the length of the hose in the portion press-fitted into the hose connection portion is Lh. When the cross-sectional area of the gap surrounded by the inner wall surface of the hose and the hose connection portion is S0 when the press-fit ratio Lh / Lp is 1, this cross-sectional area is reduced to S1 / S0 of 0.95 or less. Press the hose into the hose connection. According to such an aspect, the hose expanded by the ring-shaped protrusion can also increase the adhesion to the outer peripheral surface of the hose connection portion, thereby improving the sealing performance.

Further, as another mode for reducing the cross-sectional area of the gap, the hose connection portion has a ring-shaped projection having an outer diameter larger than the inner diameter of the hose and protruding like a mountain on the outer peripheral surface thereof. The ring-shaped projection has a curved surface where a corner rising from the outer peripheral surface of the hose connection portion is smooth, and the curved surface is formed so as to substantially follow the inner wall surface of the press-fitted hose. Can be taken.
According to this aspect, at the corner where the ring-shaped projection rises, the adhesion between the hose and the hose connection part is increased,
Sealability can be improved.

Another aspect of the present invention is a hose connection structure in which a hose is press-fitted into a hose connection portion so as to be connected to the hose connection portion, wherein the hose connection portion has an outer peripheral surface outside the inner diameter of the hose. A ring-shaped projection having a large diameter and protruding in a mountain range, and a detent projection that is close to the ring-shaped projection, has a cross-sectional shape different from the circular cross-section of the hose connection part, and stops the hose from rotating. , Is provided.

[0013] The detent projection according to another invention, when the hose is press-fitted into the hose connection portion, protrudes into the inner wall surface of the hose to prevent the hose from rotating with respect to the hose connection portion. Therefore, even if a vibration or turning force is applied to the hose, the hose is prevented from rotating with respect to the hose connection, and the tightness between the hose and the outer peripheral surface of the hose connection is not lost. Does not lead to a decline.

Still another aspect of the present invention is a hose connecting structure in which a hose is press-fitted into a hose connecting portion so as to be connected to the hose connecting portion. A ring-shaped protrusion having a large outer diameter and protruding in a mountain range is provided, and before inserting the hose into the hose connection portion, an adhesive is applied to at least one of the outer periphery of the hose or the outer periphery of the hose connection portion, The hose is press-fitted into the hose connection portion, whereby the hose and the hose connection portion are bonded by the adhesive.

In another aspect of the invention, the adhesive applied before the hose is pressed into the hose connection portion hardens with the passage of time to strengthen the connection between the hose and the hose connection portion. Therefore, even if the hose is used in a high-temperature atmosphere such as an engine room or under conditions of vibration, the pressing force on the hose connection part due to the settling of the rubber of the hose decreases, but the adhesive force due to the adhesive increases. There is no reduction in sealing performance. In addition, since the adhesive applied to the slope of the hose connection portion is particularly strongly pressed by the inner wall surface of the hose, the adhesive strength therebetween can be increased. Moreover, since the adhesive strength of the adhesive can be increased in this manner, it is possible to reduce the hose without the reinforcing yarn layer and the pipe expansion ratio.

The adhesive is not particularly limited as long as it can bond between the hose and the hose connection portion. However, the adhesive is a material which reacts and cures at a temperature in a use atmosphere of the hose joint structure. If it is, the adhesive strength can be reliably obtained, and the reliability can be improved.

The adhesive may be used alone or may be added to the insertion aid when an insertion aid for facilitating insertion of the hose into the hose connection is used. The range of application of the adhesive is not particularly limited, as long as it is within a range in which the adhesive force can be secured, in addition to part or all of the inner wall surface of the hose and the outer peripheral surface of the hose connection part.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the present invention will be described below.

FIG. 1 is a front view showing a hose coupling structure according to an embodiment of the present invention. The hose connection structure is provided in an engine room of an automobile. In FIG. 1, a hose connecting structure includes a connecting pipe 10.
And hoses 30 and 3 connected to both sides of the connection pipe 10.
1 and a branch hose 32 connected to the center of the connecting pipe 10
And The hoses 30 and 31 connect an engine and a radiator (not shown), and the branch hose 32 is connected to a throttle body.

FIG. 2 is a sectional view showing the vicinity of the connection pipe 10 and the hoses 30 and 31. The connection pipe 10 is a resin pipe body that is branched in three directions and is injection-molded using glass fiber reinforced 6-6 nylon as a material. The connection between the pipe body 11 and the hose connection integrally formed on both sides of the pipe body 11 is made. Parts 13, 14
And a branch connecting portion 15 protruding from a central portion of the pipe main body 11. Pipe body 11 and hose connection parts 13 and 14
Inside the main flow path 16 connected to the hoses 30 and 31
Are formed, and a main flow path 16 is formed in the branch connection portion 15.
A branch flow path 17 is formed which is branched and connected.

Since the hose connecting portions 13 and 14 are symmetrical and have the same configuration, the hose connecting portion 13 will be described as a representative. FIG. 3 is an enlarged sectional view showing the vicinity of the hose connection portion 13, and FIG. 5 is a diagram showing the dimensions thereof. 3 and 5, the hose connecting portion 13 is connected to hoses 30, 31.
A cylindrical portion 18 is formed by a length La from a tip end thereof, and ring-shaped projections 21, 22, 23 are formed on an outer peripheral portion thereof.

The cylindrical portion 18 has an outer diameter D2 slightly larger than the inner diameter d1 of the hose 30, and is in close contact with the hose 30 before the hose 30 is expanded by the ring-shaped protrusions 21, 22, 23. That is, the hose 30 is connected to the hose connection portion 13.
While the diameter is expanded by the ring-shaped protrusion 21 from the tip of the cylindrical portion 18, the cylindrical portion 18 is in a continuous and close contact state. Even when vibration is applied to the hose 30, such a cylindrical portion 18 maintains the hose 30 in a state in which the hose 30 is in close contact with the ring-shaped protrusions 21, 22, 23 on a smooth surface. It has improved sealing performance. The outer periphery of the distal end of the cylindrical portion 18 is connected to a hose 30
Is formed in an R shape in order to bend smoothly and to protect the inner wall surface of the hose 30.

Further, as shown in FIG.
1, 2, 23 are formed in three rows from the cylindrical portion 18 toward the center of the tube main body 11. The ring-shaped projections 21, 22, 23 are connected to the hoses from the truncated cone surfaces 21a, 22a, 23a whose outer diameters increase from the front end side to the rear end side and the maximum outer diameter of the truncated cone surfaces 21a, 22a, 23a. Extending to the general part of the part 13 and the frustoconical surface 21a,
Acute-angled surfaces 21b, 22 intersecting at acute angles with 22a, 23a
b, 23b, and each of them forms a mountain-shaped triangular cross section. The ring-shaped protrusions 21 and
2, 23 are frusto-conical surfaces 21a and acute-angle surfaces 21b, 22
Since the vertex angle between b and 23b is formed at an acute angle,
When a pulling force is applied to the hose 30, a large pull-out resistance is generated.

As shown in FIG. 2, the hose 30 has a three-layer structure having a layer formed of a reinforcing thread in a rubber tube, that is, an inner tube rubber layer 31a made of EPDM rubber.
And a reinforcing yarn layer 31b in which reinforcing yarns are braided in a spiral shape
And an outer rubber layer 31c made of EPDM rubber. The use of EPDM as a rubber material for forming the hose 30 provides a property that is excellent in ozone resistance and hardly causes cracks even when used for a long time in an expanded state.

Further, the hose 30 is inserted into the hose connection portion 13 without using a clamp or the like, is prevented from being pulled out, and has the following configuration in order to ensure a high sealing property.

FIG. 6 is an explanatory view for explaining a state in which the hose 30 is press-fitted to a portion exceeding the length of the hose connection portion 13. That is, assuming that the length of the hose connection portion 13 is Lp and the length of the hose 30 at the portion press-fitted into the hose connection portion 13 is Lh, the hose 30 has a press-fit ratio Lh
Hose connection part 1 so that / Lp becomes 1.05 to 1.4.
3 is press-fitted.

As described above, the sealability is improved by press-fitting the hose 30 to a length exceeding the insertion allowance of the hose connection portion 13, and this was examined by the following experiment. In FIG. 7, the hose connection portion 13 has one end fixed to the first fixed block B1 and protruded by a length Lp, while one end of the hose 30 is connected to Lh (=
At the position (Lha + Lhb), it is fixed to the second block B2 and protrudes from the end face of the second block B2 by the press-fit length Lhb. Then, the first and second blocks B1, B
The hose 30 is press-fitted into the hose connection part 13 by moving the hoses 2 so as to be in close contact with each other. And this hose 3
The press-fit length Lb of the hose 30 was changed by changing the position of the fixed end of 0, and in each case, the hose was exposed to an atmosphere of 120 ° C. and the sealing pressure after 250 hours was examined. FIG. 8 is a graph showing the relationship between the press-fit ratio Lh / Lp and the seal pressure. From FIG. 8, it was found that the value of the press-fit ratio Lh / Lp exceeded 1.05 and increased substantially in proportion to 1.4.

The reason why the sealing pressure increases as described above is as follows. 9A and 9B are explanatory diagrams illustrating the difference in the press-fit ratio Lh / Lp. FIG. 9A shows a case where the press-fit ratio Lh / Lp is small, and FIG. 9B shows a case where the press-fit ratio Lh / Lp is large. When the press-fitting ratio Lh / Lp is small, the gap Sp between the hose connection portion 13 and the inner peripheral surface of the hose 30 becomes large, and there are few portions where both are in close contact with each other, but as shown in FIG. As Lh / Lp increases, the area where both are in close contact increases. As described above, by increasing the area in which both are in close contact with each other, the sealing performance can be improved.

Further, in order to increase the adhesion between the hose connecting portion 13 and the hose 30 to improve the sealing performance, the following means can be used. That is, when the hose 30 is inserted into the hose connection portion 13, the ring-shaped protrusions 21,
22 and 23 increase the diameter of the hose 30, and the gap Sp between the hose 30 and the hose connection portion 13 according to the amount of the diameter increase was examined. That is, when the hose 30 is inserted into the hose connection portion 13, the hose 30 is expanded at the expansion rate T defined by the following equation (1). Here, the expansion ratio T is defined as FIG.
As shown in FIG.
It means the rate of partial expansion to the outer diameter D1, 1, 22, 23. T = (D1−d1) × 100 / d1 (1) FIG. 10 is a graph showing the relationship between the expansion ratio T and the cross-sectional area of the gap Sp. The cross-sectional area of the gap Sp when the expansion ratio T was 20%, 35%, and 45% was measured. Here, as for the cross-sectional area, an end face cut in the axial direction was photographed, and the area change was measured by image processing. It can be seen that the cross-sectional area decreases as the expansion ratio T increases. FIG. 11 shows the hose 3
5 is a graph showing the relationship between the pipe expansion ratio T and the sealing pressure at 0. As shown in FIG. 11, there is a proportional relationship between the expansion ratio T and the sealing pressure. That is, when the expansion ratio T is increased, the gap Sp becomes smaller, the area where the tube Sp adheres becomes larger, and the sealing pressure becomes larger.

In this case, the length of the hose connection portion 13 is Lp, the length of the hose 30 at the portion press-fitted into the hose connection portion 13 is Lh, and the length of the hose 30 when the press-fit ratio Lh / Lp is 1 is 1. Inner wall and hose connection 13
When the cross-sectional area of the gap surrounded by is defined as S0, the cross-sectional area of the hose 3 is set so that S1 / S0 is 0.95 or less.
0 is press-fitted into the hose connection portion 13. Also in such a mode, the hose 30 expanded by the ring-shaped protrusion 21 can increase the adhesiveness to the outer peripheral surface of the hose connection portion 13 to improve the sealing performance.

In the hose 30, the gap Sp can be reduced by reducing the inner diameter change rate Dc defined by the following equation (2). FIG. 12 shows a state where the hose 30 is expanded by receiving the internal pressure. Here, the inner diameter change rate Dc means the rate of expansion to the inner diameter d2 when the hose 30 having the inner diameter d1 receives an internal pressure of 0.49 MPa. The inner diameter d2 at the time of pressurization cannot be measured. However, since the thickness of the hose 30 hardly changes at the time of pressurization, the value obtained by measuring the outer diameter of the hose 30 and converting it to the inner diameter d2 should be used. Can be. Dc = (d2−d1) × 100 / d1 (2)

When examining the relationship between the internal pressure applied to the hose 30 and the rate of change in inner diameter Dc, there is a proportional relationship as shown by the broken straight line in FIG. In an area where the inner diameter change rate Dc exceeds 23% at an internal pressure of 0.49 MPa (an area above the solid line in the figure), a force for preventing expansion when a liquid pressure is applied becomes small, and when the diameter is expanded, The reaction force cannot be obtained sufficiently.
Therefore, the internal pressure applied to the hose 30 is 0.49
When measured on the basis of MPa, the inner diameter change rate Dc needs to be 23% or less. As described above, a small inner diameter change rate Dc with respect to the internal pressure means that the hose 30 has a high expansion resistance to the internal pressure and a small gap Sp. This characteristic is that the reinforcing yarn layer 31
It can be easily obtained by forming b.

FIG. 14 is an enlarged sectional view showing a hose coupling structure according to another embodiment. In FIG. 14, a ring-shaped protrusion 2 rising from the outer peripheral surface of the hose connection portion 13
Elastomer filling 4 that is weldable to both hose 30 and hose connection 13 at corners 1, 2, 23
Zeros are filled. As the filler 40, for example,
Silicon sealant. When the hose 30 is inserted into the hose connection portion 13, the filling 40 follows the inner wall surface of the hose 30. Therefore, the filling material 40 can be in close contact with the inner wall surface of the hose 30 without strongly press-fitting the hose 30, and the sealing property can be improved. Moreover, since the filler 40 is formed of a material having a welding property on both the hose 10 and the hose connection portion 13, it is difficult to peel off once adhered.
Sealability can be further improved. The filling 40
May be formed as a separate member or integrally with the hose connection portion 13.

FIG. 15 is a sectional view showing a hose coupling structure according to another embodiment, and FIG. 16 is a sectional view taken along line 16-16 of FIG. In FIGS. 15 and 16, a ring-shaped protrusion 2 is provided at a hose connection portion 13A of a connection pipe 10A.
1A, 22A and 23A are formed, of which a ring-shaped projection 23A is provided with a rotation preventing projection 42 as shown in FIG. The detent projections 42 are formed in a gear shape from a circular outer circumference at intervals of 60 ° in the circumferential direction. When the hose 30 is press-fitted into the hose connection portion 13A, the rotation prevention protrusion 42 protrudes into the inner wall surface of the hose 30 to prevent the hose 30 from rotating around the hose connection portion 13A in the circumferential direction. Therefore, even when vibration is applied to the hose 30, the hose 30 is not displaced in the circumferential direction with respect to the hose connection portion 13A, does not lose adhesion, and does not cause deterioration in sealing performance. Moreover, the ring-shaped protrusion 23A is formed in the third row of the ring-shaped protrusions 21A, 22A, and 23A, and high sealing performance is secured by the ring-shaped protrusion 21A in the first row. Even if the anti-rotation protrusion 42 is formed, the sealing property is not impaired.

Next, a process for facilitating the operation of inserting the hose 30 into the hose connection portion 13 will be described.
FIG. 17 is an explanatory view showing a state before the hose 30 is inserted into the hose connection section 13, and FIG. 18 is a cross-sectional view showing a state where the hose 30 is inserted into the hose connection section 13. In FIG. 17, the press-fitting operation of the hose 30 is performed using an automatic hose insertion machine 50. Fixed part 51 of hose automatic insertion machine 50
Secures the central part of the connecting tube 10 while the chuck 52
Is fixed to one end of the hose 30. Hose connection 1
The adhesive 61 is applied only in a predetermined range La from the front end of No. 3,
Also, a predetermined range Lb from the tip of the inner wall surface of the hose 30.
Only the insertion aid 62 is applied. From this state, the chuck 52 is moved to the fixing portion 51, and the hose 30 is pressed into the hose connection portion 13. At this time, the insertion aid 62 on the inner wall surface of the hose 30 and the adhesive 61 on the outer peripheral surface of the hose connection part 13 act to reduce the friction coefficient at the time of press-fitting and perform smooth press-fitting.

Here, the adhesive 61 preferably has high adhesiveness to both the hose 30 and the hose connection portion 13 and has thermosetting properties at the operating temperature of the hose 30. For example, an isocyanate-based adhesive, an epoxy-based adhesive, or the like can be used.

The insertion aid 62 has the property of reducing the coefficient of friction when the hose 30 is pressed into the hose connection portion 13, and is absorbed by the rubber of the hose 30 as time passes, so that the adhesive performance is not impaired. It preferably has properties. For example, an ester plasticizer, a paraffin oil, or the like can be used. Preferable examples of the ester plasticizer include phthalate esters such as dibutyl phthalate, di-2-ethylhexyl phthalate (DOP), and di-n-octyl phthalate.

When the press-fitting operation is completed, as shown in FIG. 18, the adhesive 61 interposed between the inner wall surface of the hose 30 and the outer peripheral surface of the hose connection portion 13 hardens over time, and The connection between the hose 30 and the hose connection part 13 is strengthened. Therefore, even if the hose 30 is used in a high-temperature atmosphere (about 120 ° C.) such as an engine room or under a condition of vibration, the pressing force on the hose connection portion 13 due to the settling of the rubber of the hose 30 is reduced. The sealability does not decrease due to the increase in the adhesive force by the adhesive 61. Moreover, the adhesive 61 a applied to the truncated cone surface 21 a of the hose connection portion 13 is
Since the pressing force is particularly strong, the adhesive force between them can be increased. Moreover, since the adhesive force of the adhesive 61 can be increased in this manner, it is possible to reduce the hose without the reinforcing yarn layer and the pipe expansion ratio.

The insertion aid 62 made of an ester plasticizer or the like is absorbed by the inner wall surface of the hose 30 with the passage of time, and the inner wall surface of the hose 30 and the hose connecting portion 1 are connected.
3 does not remain at the interface with the outer peripheral surface, so that the adhesiveness is not impaired, and hence the force for stopping the hose 30 is not reduced.

Further, in the press-fitting step of the hose 30, even if the range in which the adhesive 61 is applied is a narrow range of a predetermined range La from the tip of the hose connection portion 13, the inside of the hose 30 is pressed by the hose 30. Since it is extended almost uniformly between the wall surface and the hose connection portion 13, the amount of the adhesive 61 used may be small.

Next, the effect of the case where the hose 30 and the hose connection portion 13 were bonded with the adhesive 61 was examined by the following experiment. That is, the insertion aid 62 is attached to the inner wall surface of the hose 30.
0.15 g of (paraffin-based oil) is applied, 0.2 g of an adhesive 61 (isocyanate-based) is applied to the outer periphery of the hose connection portion 13, and the hose 30 is pressed into the hose connection portion 13 at a press-fit ratio of 1.1. Thus, a sample was prepared. In a state where an air pressure of 0.196 MPa is applied to the hose 30 applied to the sample, a vibration for elliptical movement is applied to one end of the hose 30 one million times, and then the air pressure is applied to the hose 30 to apply a pressure from the adhesive portion. The leak was checked. As a result, the adhesive 61
When not using, the air pressure is 0.5 ~ 0.7MP
a occurred, but when the adhesive 61 was used,
Even if the air pressure exceeds 0.98MPa, there is no leakage.
There was no leakage up to a. That is, the vibration test showed that the durability due to the use of the adhesive 61 was increased. As described above, the hose 30 is inserted with the press-fit ratio (1.0
5 to 1.4), the durability conditions can be sufficiently satisfied even when press-fitted. However, by using an adhesive,
Performance far exceeding endurance conditions could be obtained.

In the above embodiment, the portion to which the adhesive 61 is applied is the outer peripheral surface of the hose connection portion 13 and the portion to which the insertion aid 62 is applied is the inner wall surface of the hose 30. May be applied to part or all of the hose 30 and the hose connection part 13 with the adhesive 61 and the insertion aid 62. For example, hose connection 13
May be applied to the outer peripheral surface of the hose 30 and the adhesive 61 may be applied to the inner wall surface of the hose 30. Further, instead of the insertion aid 62, the adhesive 61 may be applied to both the inner wall surface of the hose 30 and the outer peripheral surface of the hose connection portion 13. In this case, the adhesive 61 is press-fitted due to the viscosity of the adhesive 61 itself. Can be reduced.

Further, an adhesive 61 and an insertion aid 62 compatible with the adhesive 61 are mixed, and this mixture is mixed with a hose 30.
Alternatively, by applying the adhesive to the hose connection portion 13, the amount of the adhesive to be used can be reduced, and the viscosity and reactivity of the adhesive can be adjusted, so that the handleability can be improved.

FIG. 19 is a sectional view showing a hose coupling structure according to another embodiment. In FIG. 19, the cylindrical portion 18 of the hose connection portion 13 is formed with an unevenly-shaped adhesive reinforcing portion 18 a along the outer periphery of the cylindrical portion 18. When the hose 30 is press-fitted, the adhesive 61 accumulates in the adhesion reinforcing portion 18a, and it is possible to securely adhere to the inner wall surface of the hose 30 at this portion.

FIG. 20 is a sectional view showing a hose connection structure according to still another embodiment. In FIG. 20A, the ring-shaped protrusions 21, 22, 2 of the hose connection portion 13 are shown.
In the skirt of the outer peripheral surface where no 3 is formed, the recesses 18b, 1
8c, 18d and 18e are formed. Before the hose press-fitting step, an adhesive 61b is applied to the recesses 18b to 18e in advance, or the
To 18f so that the adhesive 61b is filled.
As shown in FIG. 20B, immediately after the hose 30 is press-fitted, the inner wall surface of the hose 30 is not in close contact with the bottom such as the recess 18b. However, as shown in FIG. 20 (C), the inner wall surface of the hose 30 is deformed over time along the inclination of the ring-shaped protrusion 21 so as to follow the recess 18b or the like. Thereby, the adhesive 61 accumulated in the recess 18b is formed.
b closely adheres to the inner wall surface of the hose 30 and adheres between the hose inner wall surface and the hose connection portion 13. In this manner, the adhesive strength can be enhanced or maintained corresponding to the deformation of the hose 30 after the insertion of the hose 30.

The present invention is not limited to the above embodiment, but can be implemented in various modes without departing from the gist of the present invention. For example, the following modifications are possible.

(1) In the embodiment shown in FIG.
The ring-shaped projections 21, 22, and 23 are provided with a frustoconical surface 21a.
And the acute angle surfaces 21b, 22b, and 23b, but the shape is not limited to this, and the shape is not particularly limited as long as the diameter of the hose 30 is increased so as to generate a large sealing force. For example, the apex angle of the ring-shaped protrusion may be rounded to reduce the insertion force of the hose. In addition, the number of the ring-shaped protrusions is not particularly limited, and can be appropriately determined in consideration of the pull-out force and the insertion force of the hose, and when a plurality is provided, the size of each may be changed. .

(2) As the hose in the above-described embodiment, a hose in which a reinforcing yarn layer braided in a braided shape or spiral can be suitably used, but it contributes to reducing the gap with the hose connection portion 13. In such a configuration, a cloth may be used instead of the reinforcing thread, or a hose made of a single-layer rubber material or an elastomer may be used.

[Brief description of the drawings]

FIG. 1 is a front view showing a hose coupling structure according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the vicinity of a connection pipe 10 and hoses 30 and 31.

FIG. 3 is an enlarged sectional view showing the vicinity of a hose connection portion 13;

FIG. 4 is an enlarged sectional view showing the vicinity of ring-shaped projections 21, 22, 23;

FIG. 5 is an explanatory diagram for explaining a shape of a hose connection portion 13;

FIG. 6 is an explanatory diagram illustrating a state in which the hose 30 is press-fitted to a portion exceeding the length of the hose connection portion 13.

FIG. 7 is an explanatory diagram illustrating a step of press-fitting the hose 30.

FIG. 8 is a graph showing a relationship between a press-fit ratio Lh / Lp and a seal pressure.

FIG. 9 is an explanatory diagram illustrating a difference in press-fit ratio Lh / Lp.

FIG. 10 is a graph showing a relationship between a pipe expansion ratio T and a cross-sectional area of a gap Sp.

FIG. 11 is a graph showing a relationship between a pipe expansion ratio T and a sealing pressure in a hose 30.

FIG. 12 is an explanatory view showing a state where the hose 30 is expanded by receiving an internal pressure.

FIG. 13 is a graph showing the relationship between the inner pressure of the hose and the rate of change of the inner diameter.

FIG. 14 is an enlarged sectional view showing a hose coupling structure according to another embodiment.

FIG. 15 is a cross-sectional view showing a hose coupling structure according to still another embodiment.

FIG. 16 is a sectional view taken along the line 16-16 in FIG. 15;

FIG. 17 is an explanatory diagram illustrating a hose press-fitting step.

FIG. 18 is an enlarged sectional view showing a hose coupling structure according to another embodiment.

FIG. 19 is an enlarged sectional view showing a hose coupling structure according to still another embodiment.

FIG. 20 is an explanatory diagram showing a hose coupling structure according to another embodiment.

FIG. 21 is a partially cutaway front view showing a branch pipe 100 and the like according to a conventional hose coupling structure.

FIG. 22 is an enlarged sectional view showing the vicinity of a branch portion 101.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Connection pipe 10A ... Connection pipe 11 ... Pipe main body 13, 14 ... Hose connection part 13A ... Hose connection part 15 ... Branch connection part 16 ... Main flow path 17 ... Branch flow path 18 ... Cylindrical part 18a ... Adhesion strengthening part 18b ... Concave Locations 21, 22, 23: Ring-shaped protrusions 21a, 22a, 23a: Truncated cone surfaces 21b, 22b, 23b: Sharp surfaces 21A, 22A, 23A: Ring-shaped protrusions 30, 31, Hose 31a: Inner rubber layer 31b ... Reinforcing thread layer 31c ... Outer rubber layer 32 ... Branch hose 40 ... Filling 42 ... Detent protrusion 50 ... Hose automatic insertion machine 51 ... Fixed part 52 ... Chuck 61,61a, 61b ... Adhesive 62 ... Insertion aid

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koji Ito 1 Ogatai Ogata, Kasuga-cho, Nishikasugai-gun, Aichi F-term (reference) in Toyoda Gosei Co., Ltd. 3H017 BA01 3H019 BA04 BB06 3J023 EA10 FA03 GA02

Claims (9)

[Claims] 1. A hose connection structure for connecting a hose to a hose connection part by press-fitting the hose into the hose connection part, wherein the hose connection part has an outer diameter larger than an inner diameter of the hose on an outer peripheral surface thereof. If the length of the hose connection part is Lp, and the length of the hose at the portion press-fitted into the hose connection part is Lh, the length of the hose connection part is Lh /
A hose coupling structure wherein a hose is press-fitted into a hose connection portion such that a press-fit ratio defined by Lp is 1.05 to 1.4. 2. A hose connection structure for connecting a hose to a hose connection by press-fitting the hose into the hose connection, wherein the outer diameter of the hose connection is larger than the inner diameter of the hose and the mountain range. The length of the hose connection portion is Lp, the length of the hose at the portion press-fitted into the hose connection portion is Lh, and the press-fit ratio defined by Lh / Lp is 1 In this case, the cross-sectional area of the gap Sp surrounded by the inner wall surface of the hose and the hose connection part is S0, and the cross-sectional area when the hose is pressed into the hose connection part is S0.
A hose coupling structure, wherein S1 / S0 is set to 0.95 or less when the ratio is set to 1. 3. A hose connecting structure for connecting a hose to a hose connecting portion by press-fitting the hose into the hose connecting portion, wherein the hose connecting portion has an outer diameter larger than an inner diameter of the hose on an outer peripheral surface thereof. It comprises a ring-shaped protrusion protruding in a mountain range, and the ring-shaped protrusion has a curved surface where a corner rising from the outer peripheral surface of the hose connection portion is smooth, and the curved surface is
A hose coupling structure, which is formed so as to substantially follow the inner wall surface of the press-fitted hose. 4. A hose connection structure in which a hose is press-fitted into a hose connection portion so as to be connected to the hose connection portion, wherein the outer diameter of the hose connection portion is larger than the inner diameter of the hose and the mountain range. A ring-shaped protrusion protruding in a shape, and a detent protrusion which is close to the ring-shaped protrusion, has a cross-sectional shape different from the circular cross-section of the hose connection portion, and stops the hose from rotating. A hose coupling structure characterized by the above-mentioned. 5. A hose connection structure for connecting a hose to a hose connection portion by press-fitting the hose into the hose connection portion, wherein the hose connection portion has an outer diameter larger than an inner diameter of the hose on an outer peripheral surface thereof. A ring-shaped protrusion protruding in a mountain range is provided. Before inserting the hose into the hose connection, at least one of the inner wall surface of the hose and the outer periphery of the hose connection is coated with an adhesive, and the hose is connected to the hose. By press-fitting the connection,
A hose connection structure, wherein the hose and the hose connection portion are bonded with the adhesive. 6. The hose connection structure according to claim 5, wherein the adhesive reacts at a temperature in a use atmosphere of the hose connection structure and thermosets. 7. The hose-bonded structure according to claim 6, wherein the adhesive is an isocyanate-based adhesive. 8. The hose coupling structure according to claim 5, wherein the adhesive is used before inserting the hose into the hose connection portion.
A hose coupling structure applied to at least one of the inner wall surface of the hose and the outer periphery of the hose connection, and added to an insertion aid for facilitating insertion of the hose into the hose connection. 9. A hose connection structure in which a hose is press-fitted into a hose connection portion so as to be connected to the hose connection portion, wherein the hose connection portion has an outer diameter larger than an inner diameter of the hose on an outer peripheral surface thereof. Equipped with a ring-shaped protrusion protruding in a mountain range, before applying the hose to the hose connection, apply an adhesive to one of the inner wall surface of the hose or the outer periphery of the hose connection,
On the other hand, the hose and the hose connection were bonded by the adhesive by applying an insertion aid for facilitating insertion of the hose into the hose connection, and pressing the hose into the hose connection. A hose connection structure characterized by the above-mentioned.