JP6467133B2 - Connecting pipe structure - Google Patents

Description

  The present invention relates to a connecting pipe structure in which two connecting pipes are connected to form one flow path.

  In a vehicle engine, for example, various connection pipes through which a fluid flows are provided, such as a blow-by gas hose connected to a cylinder head and recirculating blow-by gas to a combustion chamber (Patent Document 1). When connecting such connecting pipes, it is essential to prevent fluid leakage, and various connecting pipe structures have been developed to reliably prevent leakage.

  Generally, after inserting the tip of the first connecting pipe from the opening end of the second connecting pipe, an annular fastening member is clamped (clamped) to a portion where the second connecting pipe and the first connecting pipe overlap in the radial direction (clamping). ), A connecting pipe structure that applies a surface pressure between the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe is widely adopted. In such a connection pipe structure, a bulge part in which the tip of the first connection pipe is raised in the radial direction may be provided, and it is possible to secure a sealing function by the bulge part while preventing the connection pipes from coming off by the fastening member. It is illustrated.

JP 2001-263036 A

  As described above, when the two connecting pipes are connected by the fastening member, the surface pressure may not act evenly in the circumferential direction of the connecting pipe. Thus, when the surface pressure which a fastening member acts becomes uneven in the circumferential direction of a connecting pipe, the bulge part which has a sealing function will deform | transform and there exists a subject that sealing performance falls.

  Therefore, an object of the present invention is to provide a connecting pipe structure that can suppress a decrease in sealing performance.

In order to solve the above-described problems, a connecting pipe structure according to the present invention includes a first connecting pipe, a second connecting pipe in which a tip of the first connecting pipe is inserted from an open end, and an outer peripheral surface of the second connecting pipe. Among these, the second connecting pipe and the first connecting pipe are provided in a portion overlapping in the radial direction, and a surface pressure acts between the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe. A fastening member that is positioned at least on the distal end side of the first connecting pipe relative to the fastening member, and is brought into contact with the outside by surface contact between the outer peripheral surface of the first connecting pipe and the inner peripheral face of the second connecting pipe. A seal portion that suppresses fluid leakage, and an expansion / contraction portion that is provided between the fastening member and the seal portion of the first connection pipe, and that secures stretchability in a longitudinal direction of the first connection pipe ; It is provided with.

In order to solve the above problems, the connecting pipe structure of the present invention includes a first connecting pipe, a second connecting pipe in which a tip of the first connecting pipe is inserted from an open end, and the second connecting pipe. Of the outer peripheral surface, the second connecting pipe and the first connecting pipe are provided in a portion overlapping in the radial direction, and the surface pressure is between the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe. A fastening member that causes the first connecting pipe to act, and at least one of the outer peripheral surface of the first connecting pipe and the inner peripheral face of the second connecting pipe is positioned in a radial direction at a position closer to the distal end side of the first connecting pipe than the fastening member. The bulge is raised between the bulge and the other bulge is prevented from leaking to the outside, and is provided between the fastening member and the bulge , and extends in the circumferential direction of the first connecting pipe. And a rib.

In order to solve the above problems, the connecting pipe structure of the present invention includes a first connecting pipe, a second connecting pipe in which a tip of the first connecting pipe is inserted from an open end, and the second connecting pipe. Of the outer peripheral surface, the second connecting pipe and the first connecting pipe are provided in a portion overlapping in the radial direction, and the surface pressure is between the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe. A fastening member that causes the first connecting pipe to act, and at least one of the outer peripheral surface of the first connecting pipe and the inner peripheral face of the second connecting pipe is positioned in a radial direction at a position closer to the distal end side of the first connecting pipe than the fastening member. And a bulge portion that prevents the fluid from leaking to the outside by being raised into one of the other, and the surface pressure that is provided on the distal end side of the first connecting pipe with respect to the fastening member, and on which the fastening member acts And a deformation suppressing portion that suppresses deformation of the bulge portion caused by propagation of the bulge. .

  According to the present invention, it is possible to suppress a decrease in sealing performance.

It is a figure explaining the connection pipe structure of a 1st embodiment. It is a figure explaining the connection pipe structure of a comparative example. It is a figure explaining the connecting pipe structure of 2nd Embodiment. It is a figure explaining the connecting pipe structure of 3rd Embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  In a vehicle engine, various connection pipes through which fluid flows are provided. An example of the connecting pipe is a connecting pipe that is connected to the cylinder head and recirculates the blow-by gas to the combustion chamber. The connecting pipe through which the blow-by gas circulates is configured, for example, by connecting a rubber blow-by gas hose to a resin pipe fixed to the cylinder head. Thus, in a vehicle engine, various flow paths are formed by connecting two connecting pipes made of resin, rubber, metal, or the like. In the present embodiment, a connection pipe structure that connects two connection pipes will be described in detail. However, the connection pipe structure of the present embodiment can be applied to various parts and fluids, and uses thereof are limited. is not.

  FIG. 1 is a diagram illustrating a connecting pipe structure according to the first embodiment. As shown in FIG. 1A, in the connecting pipe structure of the first embodiment, the first connecting pipe 10 and the second connecting pipe 20 are connected to each other, and the first connecting pipe is connected by a fastening member 30. 10 and the second connecting pipe 20 are prevented from coming off each other.

  The first connecting pipe 10 is made of a resin pipe, and a bulge portion 12 is formed at the tip 10a of the outer peripheral surface of the first connecting pipe 10 in the radial direction. On the other hand, the second connecting pipe 20 is made of a rubber pipe, and the inner diameter thereof is approximately equal to the outer diameter of the first connecting pipe 10 and has a dimensional relationship in which the first connecting pipe 10 can be inserted from the open end 20a. Is maintained. However, the inner diameter of the second connecting pipe 20 is smaller than the outer diameter of the bulge part 12 of the first connecting pipe 10, and the first connecting pipe 10 is press-fitted into the second connecting pipe 20 at the bulge part 12, that is, The outer peripheral surface of the first connecting pipe 10 is in a state of being bitten into the inner peripheral surface of the second connecting pipe 20. Thus, the bulge part 12 in which the outer peripheral surface of the first connection pipe 10 is press-fitted into the inner peripheral surface of the second connection pipe 20 and makes surface contact functions as a seal part S that suppresses fluid leakage to the outside.

  And the fastening member 30 is provided in the site | part with which the 2nd connection pipe 20 and the 1st connection pipe 10 mutually overlap in a radial direction among the outer peripheral surfaces of the 2nd connection pipe 20. As shown in FIG. The fastening member 30 is constituted by, for example, a bolt-tightening type clamp ring. By tightening the bolt, the inner diameter of the clamp ring is reduced, and the inner peripheral surface of the second connection pipe 20 and the first connection pipe 10 are reduced. The surface pressure acting between the outer peripheral surface is increased. In this way, the first connection from the second connection pipe 20 is caused by applying a high surface pressure between the inner peripheral surface of the second connection pipe 20 and the outer peripheral face of the first connection pipe 10 by the fastening member 30. The disconnection of the tube 10 is suppressed.

  Here, the fastening member 30 presses the outer peripheral surface of the second connection pipe 20 from the radially outer side toward the center side. This pressing force, that is, the surface pressure acting between the inner peripheral surface of the second connecting tube 20 and the outer peripheral surface of the first connecting tube 10 is the total circumferential force of the first connecting tube 10 and the second connecting tube 20. It is desirable to be even over the circumference. However, depending on the structure of the fastening member 30 to be employed and how the fastening member 30 is tightened, the surface pressure may not work evenly in the circumferential direction of the first connecting pipe 10 and the second connecting pipe 20.

  When the surface pressure applied by the fastening member 30 becomes uneven in the circumferential direction of the first connecting pipe 10 and the second connecting pipe 20, the bulge part 12 is deformed and the sealing performance as the seal part S is deteriorated. Therefore, in the connecting pipe structure of the first embodiment, the first connecting pipe 10 is provided with the expansion / contraction part 14 in order to suppress deformation of the bulge part 12 when uneven surface pressure is applied by the fastening member 30. Yes. Hereinafter, the deformation of the seal portion S in the case where the surface pressure acting in the circumferential direction of the first connection pipe 10 and the second connection pipe 20 is not uniform will be described using a comparative example, and then the telescopic portion 14. Will be described in detail.

  FIG. 2 is a diagram illustrating a connecting pipe structure of a comparative example. In the connecting pipe structure of this comparative example, a first connecting pipe 100 made of a resin pipe is provided instead of the first connecting pipe 10 in the first embodiment. The first connecting pipe 100 is different from the first connecting pipe 10 only in that it does not have the expansion / contraction part 14, and the other configuration is the same as the first connecting pipe 10.

  As shown in FIG. 2A, when the second connecting pipe 20 and the first connecting pipe 100 are tightened by the fastening member 30, as shown in FIG. 2B, the inner peripheral surface of the second connecting pipe 20 The surface pressure acting between the first connecting pipe 100 and the outer peripheral surface of the first connecting pipe 100 (indicated by the white arrow in the figure), the surface pressure in the vertical direction in the figure is greater than the surface pressure in the horizontal direction in the figure. To do. Such uneven surface pressure in the fastening member 30 propagates to the distal end 100 a side of the first connecting pipe 100.

  As a result, as shown in FIG. 2 (c), in the bulge portion 102 provided at the tip 100a of the first connection pipe 100, a force that contracts in the horizontal direction in the drawing acts and expands in the vertical direction in the drawing. A diameter force acts. At this time, if the difference between the deformation amount of the second connection pipe 20 and the deformation amount of the first connection pipe 100 is large in the bulge portion 102, the inner peripheral surface of the second connection pipe 20 and the outer periphery of the first connection pipe 100 are obtained. A gap is generated between the surface and the sealing performance is deteriorated.

  On the other hand, as shown in FIG. 1A, in the connection pipe structure of the first embodiment, the expansion / contraction part 14 is provided between the fastening member 30 and the seal part S in the first connection pipe 10. ing. The expansion / contraction part 14 is configured such that a part of the first connection pipe 10 is formed in a bellows shape (bellows shape), and between the fastening member 30 and the seal part S in the longitudinal direction of the first connection pipe 10. Ensures elasticity. By providing this stretchable part 14, as shown in FIG. 1 (b), as in the above comparative example, between the inner peripheral surface of the second connecting pipe 20 and the outer peripheral surface of the first connecting pipe 10 is provided. Even if uneven surface pressure is applied, propagation of the surface pressure to the seal portion S is absorbed by the stretchable portion 14. That is, as the expansion / contraction part 14 functions as a deformation suppressing part that suppresses deformation of the seal part S caused by propagation of the surface pressure applied by the fastening member 30, as shown in FIG. Deformation, i.e., reduction in sealing performance is suppressed.

  FIG. 3 is a view for explaining the connecting pipe structure of the second embodiment. In the said 1st Embodiment, the case where a deformation | transformation suppression part was comprised by the expansion-contraction part 14 provided in the 1st connection pipe 10 was demonstrated. The connecting pipe structure of the second embodiment is provided with a first connecting pipe 40 instead of the first connecting pipe 10 and a fixing member 50 instead of the expansion / contraction part 14 as a deformation suppressing part. Is different from the first embodiment. Hereinafter, in the description of the second embodiment, the same components as those in the first embodiment will be denoted by the same reference numerals as those described above, and description thereof will be omitted, and configurations different from those in the first embodiment will be described.

  As shown in FIG. 3A, the first connecting pipe 40 is formed of a resin pipe, and a bulge part 42 that functions as the seal part S is provided at the tip 40a. Further, the distal end 40a of the first connecting pipe 40, that is, the bulge portion 42 has a larger inner diameter than other portions, and the fixing member 50 is fitted into the inner diameter portion. The fixing member 50 is formed of an annular member having a rigidity higher than that of the first connection pipe 40, such as metal, and maintains a dimensional relationship to be fitted to the inner peripheral surface of the first connection pipe 40. Further, in a state where the fixing member 50 is fitted to the inner peripheral surface of the first connecting pipe 40, the inner peripheral surface of the first connecting pipe 40 and the inner peripheral surface of the fixing member 50 are flush with each other. The flow of the fluid flowing through the inside is not affected.

  In the connecting pipe structure of the second embodiment, the surface pressure acting between the inner peripheral surface of the second connecting pipe 20 and the outer peripheral surface of the first connecting pipe 40 that is caused by the fastening member 30 is the seal portion S. However, the fixing member 50 suppresses the deformation of the seal portion S, and thus the deterioration of the sealing performance is suppressed.

  In the second embodiment, the fixing member 50 as the deformation suppressing portion is provided on the inner diameter side of the bulge portion 42. However, the position where the fixing member 50 is provided is not limited thereto. In any case, the deformation of the seal portion S can be suppressed by providing the fixing member 50 on the distal end 40a side of the first connecting pipe 40 relative to the fastening member 30.

  Moreover, in 2nd Embodiment, although the case where the fixing member 50 was fixed to the internal peripheral surface of the 1st connection pipe 40 was demonstrated, you may fix the fixing member 50 to the outer peripheral surface of the 1st connection pipe 40. In any case, the fixing member 50 as the deformation suppressing portion may be provided on the inner peripheral surface or the outer peripheral surface of the first connection pipe 40. Furthermore, although the case where the fixing member 50 is made of metal and is configured by an annular ring member has been described here, the material and shape of the fixing member 50 are not particularly limited. Even if the fixing member 50 has a shape that extends not over the entire circumference in the circumferential direction of the first connecting pipe 40 but over a part thereof, the effect of suppressing the deformation of the seal portion S can be obtained. .

  FIG. 4 is a view for explaining the connecting pipe structure of the third embodiment. The connecting pipe structure of the third embodiment is different from the first embodiment in that a first connecting pipe 60 is provided instead of the first connecting pipe 10. Hereinafter, in the description of the third embodiment, the same components as those of the first embodiment will be denoted by the same reference numerals as those described above, and the description thereof will be omitted, and configurations different from those of the first embodiment will be described.

  As shown in FIG. 4, the first connection pipe 60 is formed of a resin pipe, and a bulge portion 62 that functions as the seal portion S is provided at the tip 60 a. Further, a rib 64 extending in the circumferential direction of the first connection pipe 60 is formed between the fastening member 30 and the seal portion S in the first connection pipe 60. The rib 64 is configured by raising the outer peripheral surface of the first connecting pipe 60 in an annular shape over the entire circumference in the circumferential direction. That is, the rib 64 is integrally formed with the first connecting pipe 60, and the first connecting pipe 60 has a diameter at the rib 64 larger than the diameter at other portions, and the rib 64 is formed on the inner peripheral surface of the second connecting pipe 20. Is biting in.

  In the connection pipe structure of the third embodiment, the surface pressure acting between the inner peripheral surface of the second connection pipe 20 and the outer peripheral surface of the first connection pipe 60, which is provided by the fastening member 30, is the seal portion S. However, the rib 64 suppresses the deformation of the seal portion S. That is, since the rib 64 functions as a deformation suppressing portion, the deterioration of the sealing performance is suppressed as in the first and second embodiments.

  In the third embodiment, the case where the ribs 64 extend over the entire circumference in the circumferential direction of the first connection pipe 60 has been described. However, the ribs 64 are all in the circumferential direction of the first connection pipe 60. Even if it is a shape that extends over a part rather than the circumference, the effect of suppressing the deformation of the seal portion S can be obtained. Although the case where the rib 64 is integrally formed with the first connection pipe 60 has been described here, the rib 64 may be formed separately from the first connection pipe 60.

  Moreover, in the said 1st-3rd embodiment, although it was decided to provide either the expansion-contraction part 14, the fixing member 50, or the rib 64 as a deformation | transformation suppression part, the expansion-contraction part 14, the fixing member 50, Any two or more of the ribs 64 may be provided in combination. That is, all of the expansion / contraction part 14, the fixing member 50, and the rib 64 may be included in the deformation suppressing part.

  In the first to third embodiments, the bulge portions 12, 42, 62 are provided as the seal portion S. However, in each embodiment, the bulge portions 12, 42, 62 are not essential components. In any case, it is located at least on the distal end side of the first connecting pipe 10, 40, 60 from the fastening member 30, and the outer peripheral surface of the first connecting pipe 10, 40, 60 and the inner peripheral surface of the second connecting pipe 20 It is only necessary to provide a seal portion S that prevents leakage of fluid to the outside by surface contact. Therefore, for example, even if the outer diameters of the first connecting pipes 10, 40, 60 and the inner diameter of the second connecting pipe 20 are constant in the longitudinal direction, the first connecting pipe 10, It is only necessary to maintain a dimensional relationship in which the outer peripheral surfaces of 40 and 60 and the inner peripheral surface of the second connection pipe 20 are in close contact with each other. In this case, the close contact portion functions as the seal portion S. It will be.

  The materials of the first connecting pipes 10, 40, 60, the second connecting pipe 20, and the fastening member 30 in the first to third embodiments are merely examples. In any case, it is only necessary to have a relationship that can prevent the first connecting pipes 10, 40, 60 and the second connecting pipe 20 from being detached by tightening the fastening member 30.

  Moreover, although the said 1st-3rd embodiment demonstrated the connecting pipe structure used for the engine for vehicles, each said connecting pipe structure is applicable not only to the engine for vehicles but in all technical fields. .

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiments, and various modifications within the scope described in the claims. Needless to say, the modified examples also belong to the technical scope of the present invention.

  The present invention can be used for a connecting pipe structure in which two connecting pipes are connected to form one flow path.

10, 40, 60 First connecting pipe 10a, 40a, 60a Tip 12, 42, 62 Bulge part 14 Stretching part 20 Second connecting pipe 20a Open end 30 Fastening member 50 Fixing member 64 Rib S Seal part

Claims (3)

A first connecting pipe;
A second connecting pipe in which a tip of the first connecting pipe is inserted from an open end;
Of the outer peripheral surface of the second connecting pipe, the second connecting pipe and the first connecting pipe are provided in a portion where they overlap in the radial direction, and the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe A fastening member that exerts a surface pressure between
Positioned at least on the distal end side of the first connecting pipe relative to the fastening member, fluid leakage to the outside is suppressed by surface contact between the outer peripheral face of the first connecting pipe and the inner peripheral face of the second connecting pipe. Sealing part to be
An expansion / contraction part that is provided between the fastening member and the seal part in the first connection pipe, and secures stretchability in the longitudinal direction of the first connection pipe;
A connecting pipe structure characterized by comprising: A first connecting pipe;
A second connecting pipe in which a tip of the first connecting pipe is inserted from an open end;
Of the outer peripheral surface of the second connecting pipe, the second connecting pipe and the first connecting pipe are provided in a portion where they overlap in the radial direction, and the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe A fastening member that exerts a surface pressure between
At least one of the outer peripheral surface of the first connecting tube and the inner peripheral surface of the second connecting tube is located at the tip side of the first connecting tube relative to the fastening member. A bulge that cuts into the fluid and prevents leakage of fluid to the outside,
A rib provided between the fastening member and the bulge portion and extending in a circumferential direction of the first connecting pipe;
A connecting pipe structure characterized by comprising: A first connecting pipe;
A second connecting pipe in which a tip of the first connecting pipe is inserted from an open end;
Of the outer peripheral surface of the second connecting pipe, the second connecting pipe and the first connecting pipe are provided in a portion where they overlap in the radial direction, and the inner peripheral surface of the second connecting pipe and the outer peripheral surface of the first connecting pipe A fastening member that exerts a surface pressure between
At least one of the outer peripheral surface of the first connecting tube and the inner peripheral surface of the second connecting tube is located at the tip side of the first connecting tube relative to the fastening member. A bulge that cuts into the fluid and prevents leakage of fluid to the outside,
A deformation suppressing portion that is provided on the distal end side of the first connecting pipe with respect to the fastening member and suppresses deformation of the bulge portion caused by propagation of the surface pressure that the fastening member acts;
A connecting pipe structure characterized by comprising:

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