JP2020041633A - Piping connection structure and connection member - Google Patents

Abstract

To provide a piping connection structure capable of suppressing influence on a seal surface pressure by eccentricity and improving assemblability in connecting with piping, and a connection member used in the same.SOLUTION: In a piping connection structure for connecting first piping 1 and second piping 2 opposed to each other through a connection member 3 in a state of axially separating from each other in a through hole 10 of a wall body 101, the connection member is a cylindrical body having a first holding portion 30 externally fitted to the first piping and internally fitted to the through hole, a second holding portion 40 externally fitted to the second piping, and a joint portion 50 for joining the first holding portion and the second holding portion. An outer peripheral lip portion 31 elastically kept into contact with an inner peripheral surface 10a of the through hole with an interference in accompany with bending deformation, is disposed on an outer peripheral surface 30b of the first holding portion, and an outer peripheral projection portion 51 being close to or kept into contact with the inner peripheral surface of the through hole is disposed at a second holding portion side of the outer peripheral lip portion.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pipe connection structure for connecting a first pipe and a second pipe which are opposed to each other in an axially separated state in a through hole of a wall body, and a connection member used for the pipe connection structure.

For example, an automotive inverter incorporates an internal pipe through which a cooling medium flows in an inverter case. The internal pipe is connected to an external pipe connected to a converter through a through hole provided in a wall of the inverter case. Patent Literature 1 listed below relates to a connection structure for connecting such an internal pipe and an external pipe.
Patent Literature 1 below discloses a pipe connection structure using a connection member having two grip portions attached to each of two pipes and a connecting portion connecting the two grip portions. .

JP-A-2005-227701

  Incidentally, the two pipes as described above may be eccentric due to vibration or thermal swelling depending on the material of the pipes. At this time, it is desirable that the seal surface pressure of each of the two grip portions is not affected. Also, for example, when connecting the other pipe with the connection member attached to one of the two pipes, the connecting portion of the connection member is buckled or depressed by an insertion load, and is difficult to insert. May be a problem.

  The present invention has been made in view of the above circumstances, and has a pipe connection structure capable of suppressing the influence of eccentricity on a seal surface pressure and improving assemblability when connecting to a pipe, and a connection used therefor. It is intended to provide a member.

In order to achieve the above object, a pipe connection structure according to the present invention includes a first pipe and a second pipe, which are disposed opposite to each other in an axially separated state in a through hole of a wall, via a connection member. A pipe connection structure for connecting, wherein the connection member is firstly fitted to the first pipe and internally fitted in the through hole, and second holding part is externally fitted to the second pipe. And a cylindrical body having a connecting portion that connects the first holding portion and the second holding portion. The outer circumferential surface of the first holding portion is bent and deformed into the inner circumferential surface of the through hole. And an outer peripheral lip portion which is elastically contacted with an interference with the outer peripheral lip portion is provided on the second holding portion side of the outer peripheral lip portion so as to approach or contact the inner peripheral surface of the through hole. Is provided.
The connection member according to the present invention is a connection member used for the pipe connection structure, wherein the first holding portion is mounted on a connection end of the first pipe, and the connection member is mounted on a connection end of the second pipe. A second holding portion to be connected and an elastically deformable connecting portion connecting the first holding portion and the second holding portion.

  The pipe connection structure according to the present invention and the connection member used for the pipe connection structure are configured as described above, thereby suppressing the influence of the eccentricity on the seal surface pressure and improving the assemblability when connecting to the pipe. Can be.

It is sectional drawing which showed typically the piping connection structure which concerns on this invention, and the principal part which concerns on one Embodiment of the connection member used for it. FIG. 2 is a partially enlarged cross-sectional view schematically showing the connecting member according to the same embodiment (an X-partial enlarged view of FIG. 1). It is a figure for demonstrating the piping connection structure which concerns on the same embodiment, and the connection member used for it, and is sectional drawing which shows typically the state which the 2nd piping was eccentric. It is a figure for demonstrating the piping connection structure which concerns on the same embodiment, and the connection member used for this, and is sectional drawing which shows typically the state after connecting piping. It is a figure for demonstrating the piping connection structure which concerns on the same embodiment, and the connection member used for this, and is sectional drawing which shows typically the state which pulls out one of the connected piping.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In some of the drawings, some of the detailed reference numerals attached to other drawings are omitted. Also, in FIG. 1, in order to easily understand the shapes of the components of the connection member 3, the connection member 3 having the original shape that has not been elastically deformed is shown by a solid line, but actually, as shown in FIGS. Assembled in an elastically deformed state.

  In the pipe connection structure according to the present embodiment, the first pipe 1 and the second pipe 2 which are opposed to each other in the through hole 10 of the wall body 101 while being separated in the axial direction are connected via the connection member 3. It is a pipe connection structure. The connection member 3 includes a first holding portion 30 externally fitted to the first pipe 1 and internally fitted into the through hole 10, a second holding portion 40 externally fitted to the second piping 2, and a first holding portion. It is a tubular body having a connecting portion 50 connecting the second holding portion 40 and the second holding portion 40. On the outer peripheral surface of the first holding portion 30, an outer peripheral lip portion 31 that elastically contacts the inner peripheral surface 10a of the through hole 10 with an interference due to bending deformation is provided. On the side of the second holding portion 40 of the outer peripheral lip portion 31, there is provided an outer peripheral protruding portion 51 approaching or abutting toward the inner peripheral surface 10 a of the through hole 10.

  The pipe connection structure of the present embodiment can be applied, for example, as a structure that connects a cooling pipe of a cooler that cools an electronic device for a vehicle with a refrigerant and an external hose. In this case, it is required not only to prevent the leakage of the refrigerant but also to withstand the intrusion of rainwater and the like from the outside and the injection of water at the time of high-pressure washing of a vehicle or the like, and further, it is required to have a sealing property capable of maintaining the eccentricity of the piping. In addition to having such a sealing property, as described above, it is also required to suppress the influence of the eccentricity on the sealing surface pressure and to improve the assembling property when connecting the pipes. In the following, a description will be given of a pipe connection structure in which the second pipe 2 provided in the automobile inverter case 100 and the first pipe 1 provided outside the inverter case 100 are connected by the connection member 3.

  In the case of a motor equipped with a motor as a drive source of an automobile, the operation of the motor is controlled by an inverter. The motor works as a motor or the like that generates driving force by obtaining power from a battery, and the inverter converts a DC power supplied from the battery or the like into an AC power by a switching action to supply power to the motor. An inverter used in such an automobile requires a large amount of electric power, and a large amount of current flows through a switching element or the like, and thus generates a large amount of heat. Therefore, a system for cooling the inverter by forming a coolant flow path in which a coolant such as cooling water or a coolant flows in the inverter case 100 accommodating the inverter is employed.

<Piping connection structure>
The inverter case 100 is a box having a substantially rectangular parallelepiped shape which is divided into upper and lower parts, and includes an upper case and a lower case shown as a wall 101 in FIG. The inverter case 100 is configured to be joined so as to cover the substantially concave upper case in cross section on the substantially concave lower case in cross section. It is said. The inverter case 100 is made of a metal material such as aluminum. In the inverter case 100, a refrigerant flow path for circulating a coolant such as cooling water or a cooling liquid for cooling the inverter is provided. The (cooling pipe) is provided so as to constitute a part of the refrigerant flow path. A semicircular cutout hole is formed in a side wall of the upper case and the lower case at a position facing each other so as to form a through hole 10 when the two cases are joined to form an inverter case 100. As shown in FIG. 1, the second pipe 2 is disposed such that the leading end of the connection end 2 a is located in the through hole 10. When looking inside, the front side of the connection end 2a of the second pipe 2 can be visually recognized. The shape of the through hole 10 is not particularly limited, and is formed according to the shape and size of the first pipe 1 (external hose) connected to the second pipe 2. The diameter of the through hole 10 is formed to be larger than the outer diameter of the first pipe 1 to be inserted.
Here, the second pipe 2 will be described as constituting a part of the coolant flow path, but is not limited thereto, and may be in communication with a separately provided coolant flow path. In the drawing, L indicates the axis of the through hole 10 provided in the inverter case 100, L1 is the axis of the first pipe 1, L2 is the axis of the second pipe 2, and L3 is the axis of the connection member 3. Is shown. Therefore, as shown in FIG. 1, a state where the axes L and L1 to L3 coincide with each other is desirable as the connection state. However, the connection structure of the present embodiment is a structure that assumes that these axes L to L3 are eccentric. It is.

<Connecting member>
The connection member 3 is a member for connecting the first pipe 1 and the second pipe 2 to form a refrigerant channel, and is entirely made of a rubber material such as ethylene propylene rubber, butyl rubber, silicone rubber, an elastomer, or a synthetic resin. It is a cylindrical molded body made of an elastic body made of the same. The connecting member 3 has a first holding portion 30, a second holding portion 40, and a connecting portion 50. One end 3a of the connecting member 3 is an end of the first holding portion 30, and the other end 3b is It is an end of the second holding section 40. The first holding portion 30 is externally fitted so as to cover the connection end 1 a of the first pipe 1 and is also internally fitted to the inner peripheral surface 10 a of the through hole 10. The second holding portion 40 is fitted externally so as to cover the connection end 2 a of the second pipe 2. The connecting portion 50 is a member that connects the first holding portion 30 and the second holding portion 40. Since the connecting portion 50 itself has elasticity, the first pipe 1 and the second pipe 2 are eccentric. Also, radial displacement is possible.
The outer diameter of the first pipe 1 is slightly larger than the outer diameter of the second pipe 2, and accordingly, the inner diameter of the first holding section 30 is larger than the inner diameter of the second holding section 40. Therefore, the connecting portion 50 that connects the first holding portion 30 and the second holding portion 40 has a tapered shape that gradually decreases in diameter from the first holding portion 30 to the second holding portion 40.

<First piping, second piping>
The first pipe 1 is made of a hollow cylindrical body such as a resin material or an aluminum material, and is configured to send a refrigerant to a second pipe 2 serving as a refrigerant flow path circuit in the inverter case 100. The second pipe 2 is made of a hollow cylindrical body such as a resin material or an aluminum material, and the refrigerant supplied from the first pipe 1 flows through the inside.
The connection end 1a of the first pipe 1 has an annular recess 11 into which the first holding portion 30 of the connection member 3 is fitted, and an annular recess formed on the outer periphery of the recess 11 so as to project radially outward. A flange 12 is provided. The concave portion 11 has a bottom portion 11c, an inner wall 11a serving as an outer peripheral surface 1aa of the first pipe 1, an outer wall 11b, and an opening 11d. The first holding portion 30 of the connection member 3 is fitted into the concave portion 11. A streak-like slit portion (not shown) serving as an air passage may be formed along the axial direction at the fitting portion between the concave portion 11 and the first holding portion 30. If the slit portion is formed along the outer wall 11b so as to extend from the bottom 11c of the concave portion 11 to the opening 11d, when the first holding portion 30 is fitted, air escapes from the slit portion and the connecting member 3 It is easy to insert the first holding portion 30 into the outer peripheral surface 1aa of the first pipe 1 (which also corresponds to the inner wall 11a of the concave portion 11). In a state where the first pipe 1 and the second pipe 2 are connected by the connecting member 3, the flange 12 has a diameter larger than the through hole 10 so as to abut on the wall body 101. An insertion hole (not shown) through which a fixture such as a screw or the like is inserted is formed. Then, the first pipe 1 which is an external pipe is fixed to the wall body 101 by fixing the flange portion 12 to the outer surface of the wall body 101 with a fixture (not shown).
On the other hand, the leading end of the connecting end 2a of the second pipe 2 is provided with a slanting leading end 2ab whose diameter is slightly smaller than other parts so that the connecting member 3 can be easily detached.
In addition, the recess 11 and the flange 12 may be formed integrally with the first pipe 1 as shown in FIG. 1, or may be configured to be fitted separately into a cylindrical pipe.

<First holding unit>
The first holding unit 30 has an inner peripheral lip 32, an inner peripheral protrusion 33, an outer peripheral lip 31, a flat part 34, and an end 35. The inner peripheral lip portion 32 is an annular lip that is continuous in the circumferential direction, elastically contacts the outer peripheral surface 1aa of the first pipe 1, and the inner peripheral lip portion 32 is fitted into the concave portion 11 while being elastically deformed. The inner peripheral projection 33 is provided adjacent to the inner peripheral lip 32. The outer peripheral lip portion 31 is an annular lip that is continuous in the circumferential direction, and elastically contacts the inner peripheral surface 10a of the through hole 10 with an interference due to bending deformation. The protrusion amount of the outer lip portion 31 is larger than the protrusion amount of the inner lip portion 32. The flat portion 34 is formed flat so as to abut along the outer wall 11b of the recess 11. The end 35 is formed flat so as to abut along the bottom 11 c of the recess 11. A plurality of the inner peripheral lip portions 32 are provided side by side, and a region on the inner peripheral side where the plurality of inner peripheral lip portions 32, 32 are arranged is referred to as an inner seal region S1. Further, a region on the outer peripheral side where the outer peripheral lip portion 31 is disposed is referred to as an outer seal region S2. The inner seal area S1 and the outer seal area S2 are provided at positions that do not overlap in the radial direction.

As described above, since the inner seal region S1 and the outer seal region S2 are provided at positions that do not overlap in the radial direction, in a state where the connecting member 3 is fitted and assembled to the connecting end 1a of the first pipe 1, At the time of insertion into the through hole 10 of the wall body 101, it is possible to prevent an increase in the insertion load and to improve the assembling property. Also, even when the axis L1 of the first pipe 1 and the axis L of the through hole 10 are shifted and eccentric, the eccentricity is provided because the inner seal area S1 and the outer seal area S2 do not overlap in the radial direction. The sealing performance can be maintained without being affected by the surface pressure fluctuation and the internal stress of the inner and outer seal regions S1 and S2 at the time.
Further, the inner seal region S1 is provided on the opposite side of the outer seal region S2 with respect to the insertion direction of the first pipe 1, and an outer peripheral surface corresponding to a portion where the inner seal region S1 is formed is a flat portion 34, and the first seal region S1 is formed. Fitted in the recess 11 of the pipe 1. Therefore, even if the first pipe 1 is eccentric, the hermeticity of the first pipe 1 is maintained by the plurality of inner peripheral lip portions 32, 32 arranged in the inner seal area S1, and a stable sealing property can be secured.

The inner peripheral projection 33 is provided adjacent to the inner peripheral lips 32, 32 provided in the inner seal region S1, and is formed on the inner peripheral surface 30a corresponding to the position where the outer peripheral lip 31 is formed. This serves as a support for generating the surface pressure of the outer peripheral lip portion 31. The inner peripheral projection 33 may be formed continuously along the circumferential direction, or may be formed at appropriate intervals. As shown in FIG. 3, the inner peripheral lip portion 32 is formed to have a length enough to be elastically deformed and fall down, and a resilient contact portion that resiliently contacts the inner wall 11a is formed in a tapered cross-sectional mountain shape. The inner peripheral projection 33 is formed in a mountain-shaped cross-section with a projection amount smaller than the inner peripheral lip 32.
Since the inner peripheral projection 33 is provided on the inner peripheral surface 30a corresponding to the position where the outer peripheral lip portion 31 is formed, even if a force for eccentricity is applied to the first pipe 1, The posture can be held at a correct position (a position where the axis L1 of the first pipe 1 and the axis L of the through hole 10 substantially match). Also, even when the first pipe 1 is eccentric, the inner peripheral projection 33 abuts on the outer peripheral surface 1aa of the first pipe 1 to suppress overcompression of the inner peripheral lip portion 32, and the sealing surface pressure of the inner peripheral lip portion 32 is reduced. , It is possible to maintain a stable sealing property. Further, when the pressure of the refrigerant passing through the first pipe 1 rises, the first holding portion 30 attached to the first pipe 1 generates a force to pull out from the concave portion 11, but the inner peripheral lip portion 32 and the inner peripheral protrusion are formed. The first pressing portion 33 acts to prevent the first holding portion 30 from coming off.
In the present embodiment, an example in which the inner peripheral projection 33 abuts on the outer peripheral surface 1aa of the first pipe 1 is elastically contacted when it is eccentric. 1aa may be approached (with a slight gap).

  The outer peripheral surface 30b of the first holding portion 30 is provided with an outer peripheral lip portion 31 that abuts on the inner peripheral surface 10a of the through hole 10 in an elastically deformed state. As shown in FIG. 2, the outer peripheral lip portion 31 has one surface 31A opposite to the insertion direction of the first pipe 1 in a straight line shape, and the other surface 31B gradually tapers toward the tip. It is inclined. A base portion of the outer peripheral lip portion 31 on one surface 31A has a bent portion 31b which becomes a bending point of the outer peripheral lip portion 31 when elastically contacting the inner peripheral surface 10a of the through hole 10. The bent portion 31b is an intersection of the inclined portion 31a formed to be inclined from the outer peripheral surface 30b to the one surface 31A and the one surface 31A. Further, the outer peripheral lip portion 31 is deformed into a collapsed state as shown in FIG. 3 and elastically contacts the inner peripheral surface 10 a of the through hole 10. Therefore, even when the first pipe 1 or the second pipe 2 is eccentric as shown in FIG. 3, the sealing property with the inner peripheral surface 10 a of the through hole 10 can be maintained, and the high responsiveness due to the bending deformation of the outer peripheral lip portion 31. Can be realized. Further, when the outer peripheral lip portion 31 is elastically contacted with the inner peripheral surface 10a of the through hole 10, the outer peripheral lip portion 31 can be bent with the bent portion 31b as a bending point, and the bent portion 31b is at the base of the outer peripheral lip portion 31. Therefore, it is possible to bend not to bend smoothly but to be sharply bent. Thereby, the insertion load when inserting the first pipe 1 into the through hole 10 can be reduced, and the insertion performance can be improved. Further, the contact surface of the outer peripheral lip portion 31 with the inner peripheral surface 10a of the through hole 10 is widened, and the sealing performance is improved. Further, the contact surface of the outer lip portion 31 can be widened, so that the inner peripheral surface 10a of the through-hole 10 has a cavity, a flaw, a foreign substance, etc., or the surface of the outer lip portion 31 is slightly undulating or twisted. In this case, the sealing function can be maintained.

<Connecting part>
The connecting portion 50 connects the first holding portion 30 attached to the connection end portion 1a of the first pipe 1 and the second holding portion 40 attached to the connection end portion 2a of the second pipe 2, and is elastically deformable. It has been. Since the first holding part 30 and the second holding part 40 have different diameters depending on the diameters of the first pipe 1 and the second pipe 2, the connecting part 50 is tapered. That is, the connecting portion 50 is formed to be inclined with respect to the axis L3 of the connecting member 3, and the connecting portion 50 has an angle. Therefore, when the connection member 3 is molded, the connection member 3 plays a role of draft and is easily released.

The connecting portion 50 is provided with an outer peripheral protruding portion 51 which is adjacent to the insertion direction side (the second holding portion 40 side) of the outer peripheral lip portion 31 and has a mountain-shaped cross section and elastically contacts the inner peripheral surface 10 a of the through hole 10. ing. The outer peripheral protrusions 51 may be formed continuously along the circumferential direction, or may be formed at appropriate intervals. The outer peripheral protruding portion 51 is formed in a mountain-shaped cross section having a protruding amount smaller than the outer peripheral lip portion 31.
In the present embodiment, an example in which the outer peripheral projection 51 abuts on the inner peripheral surface 10a of the through hole 10 is illustrated, but is close to the inner peripheral surface 10a (with a slight gap), and The pipe 1 or the second pipe 2 may be elastically contacted when eccentric.

FIG. 3 is a sectional view showing a state where the second pipe 2 is eccentric.
As shown here, since the outer peripheral projection 51 is provided adjacent to the outer peripheral lip portion 31 in the insertion direction, even when the second pipe 2 is eccentric, the outer peripheral projection 51 is formed on the inner periphery of the through hole 10. The contact with the surface 10a suppresses the overcompression of the outer peripheral lip portion 31, prevents the seal surface pressure of the outer peripheral lip portion 31 from being affected, and maintains the sealing property. In addition, even when the first pipe 1 is eccentric, the outer peripheral projection 51 can reliably contact the inner peripheral surface 10a of the through hole 10 to maintain the posture of the first pipe 1 to be eccentric at a correct position. The same effect can be obtained.

As described above, the space between the inner peripheral surface 10a of the through hole 10 and the connection member 3 is sealed by the outer peripheral lip portion 31, and the axis L1, L2 of the first pipe 1 and the second pipe 2 is eccentric in either direction. In such a case, the connecting member 3 is supported by the outer peripheral protrusion 51 abutting on the inner peripheral surface 10 a of the through hole 10, and the first pipe 1 and the second pipe 2 of the first holding section 30 and the second holding section 40 are provided. The influence on the seal surface pressure on the pipe 2 can be suppressed. In addition, since the connecting member 3 is supported by the outer peripheral projection 51 and dents and buckling due to radial displacement are prevented, the first pipe 1 is inserted into the through hole 10 and the second pipe 2 is connected to the connecting member 3. 3 can be easily assembled.
In the present embodiment, the outer peripheral protrusion 51 is provided on the first holding portion 30 side of the connecting portion 50 and abuts on the inner peripheral surface 10 a of the through hole 10. Any structure may be used as long as it is provided on the holding part 40 side and approaches or contacts the inner peripheral surface 10a of the through hole 10. For example, instead of disposing the outer peripheral projection 51 on the connecting part 50, the first holding part An outer peripheral projection 51 may be provided on the side of the outer peripheral lip 31 of the outer peripheral lip 31 on the second holding portion 40.

<Second holding unit>
The inner peripheral surface 40a of the second holding portion 40 has a lip forming area A in which an annular lip portion 42 is provided in contact with the outer peripheral surface 2aa of the second pipe 2. An annular concave portion 41 having a bottom portion 41b and a pair of groove wall portions 41a, 41a is provided on an outer peripheral surface 40b of the second holding portion 40 corresponding to the lip formation region A formed on the inner peripheral surface 40a. Have been. The concave streak portion 41 is formed in an annular shape along the circumferential direction, and the concave streak portion 41 accommodates a reinforcing ring 4 for reinforcing the fitting to the second pipe 2 in a fitted state. The reinforcing ring 4 is an annular body made of a metal material, a synthetic resin material, or the like, and is formed according to the groove depth and groove width of the concave streak portion 41. The reinforcing ring 4 is arranged on the outer peripheral surface 40b of the second holding portion 40 corresponding to the lip forming area A. When the reinforcing ring 4 is housed in the concave streak portion 41 of the second holding portion 40 and is externally fitted to the second pipe 2, the reinforcing ring 4 exerts a tightening action in the centripetal direction, and the reinforcing ring 4 and the lip portion The sealing force of the second pipe 2 to the second pipe 2 can be strengthened, and the second pipe 2 can be held more stably.

  A protrusion 43 is formed on an end of the second holding portion 40, that is, on the other end 3 b side of the connection member 3, adjacent to the lip 42. The protruding portion 43 is formed continuously along the circumferential direction, and the top is formed in a mountain-shaped cross section inclined to the opposite side to the insertion direction so that the connecting member 3 can be easily inserted into the second pipe 2. Have been. The protrusion 43 is formed so as to elastically contact the outer peripheral surface 2aa of the second pipe 2. The amount of protrusion of the protrusion 43 and the distance between the adjacent lip portion 42 can be determined even when the protrusion 43 is fitted to the outer peripheral surface 2aa of the second pipe 2 and the top portion is slightly elastically deformed and falls down to the lip portion 42 side. It is preferable that the protrusions 43 and the protrusions 43 are formed such that they do not abut on the lip portions 42 and are spaced apart from each other, and the protrusion amount of the protrusions 43 is smaller than the protrusion amount of the lip portions 42.

  The bottom portion 41b of the concave streak portion 41 provided on the second holding portion 40 has a contact portion 41ba that contacts the inner peripheral surface 4a of the reinforcing ring 4 and a concave depression that does not contact the inner peripheral surface 4a of the reinforcing ring 4. Part 41c. The contact portion 41ba is formed at a position corresponding to the region of the connecting portion side 42a (the one end 3a side of the connecting member 3) of the plurality of lip portions 42 and the connecting portion side 43a of the protrusion 43. The recess 41c is formed at a position corresponding to the region of the lip portion 42 on the side opposite to the joint portion 42b (on the other end 3b side of the connection member 3).

  Since the bottom portion 41b provided on the outer peripheral surface 40b of the second holding portion 40 has the concave portion 41c as described above, a gap is formed between the reinforcing ring 4 and the outer peripheral surface 40b of the second holding portion 40. I can do it. Thereby, the contact area between the reinforcing ring 4 and the second holding portion 40 is reduced, and the lip portion 42 generated when the second holding portion 40 in which the reinforcing ring 4 is externally fitted is inserted into and pulled out from the second pipe 2. The surface pressure can be reduced, and the insertion and withdrawal load can be reduced. Further, since the concave portion 41c is formed in the concave streak portion 41 in which the reinforcing ring 4 is accommodated, when the reinforcing ring 4 itself is externally fitted to the outer peripheral surface 40b of the second holding portion 40, the contact surface is reduced, The effect of reducing the resistance due to friction and facilitating the assembly of the reinforcing ring 4 is also achieved. Further, the contact portion 41ba is formed at a position corresponding to the region of the connecting portion side 42a of the lip portion 42 and the region of the connecting portion side 43a of the protruding portion 43. Since it is formed at a position corresponding to the area, after the insertion, the sealing surface pressure of the lip portion 42 can be appropriately secured, and the insertion and withdrawal load of the connecting member 3 can be reduced.

  Each of the plurality of lip portions 42 has the same substantially identical mountain-shaped cross section, and is formed in an annular shape along the circumferential direction. The contact portion 41ba may be annularly provided in the circumferential direction similarly to the lip portion 42, but may be formed discontinuously at appropriate intervals. Since the contact portion 41ba is formed at a position corresponding to the region of the connecting portion side 42a of the lip portion 42, the contact portion 41ba is inclined toward the connecting portion 50 when the second holding portion 40 is inserted into the second pipe 2. Since the lip portion 42 elastically deformed is supported by the reinforcing ring 4 via the contact portion 41ba, the sealing surface pressure can be further increased, and the sealing performance can be improved.

The depression 41c formed in the bottom 41b is formed at a position corresponding to a region where the lip portion 42 is not formed from a position corresponding to the region on the anti-joining portion side 42b of the lip portion 42. Specifically, in the example shown in FIG. 1, a total of three recesses 41 c are formed, and among these, the recess 41 c provided closest to the connecting portion 50 side is a lip portion arranged on the connecting portion 50 side. The portion 42 is formed from a position corresponding to the region on the opposite connecting portion 42b side to a position corresponding to the region on the connecting portion side 42a of the adjacent central lip portion 42. The second recessed portion 41c from the connecting portion 50 side also corresponds to the region of the connecting portion side 42a of the adjacent lip portion 42 from the position corresponding to the region of the central lip portion 42 on the opposite connecting portion side 42b. It is formed to the position where it does. The recessed portion 41c provided on the other end 3b side is connected to the connecting portion side of the projection 43 formed on the other end 3b side from a position corresponding to the region of the opposite lip portion 42b of the lip portion 42 on the other end 3b side. It is formed up to a position corresponding to the area 43a.
The depression 41c provided in this manner sufficiently reduces the surface pressure of the lip 42 generated when the second holding portion 40 with the reinforcing ring 4 fitted to the second pipe 2 is inserted and withdrawn when the second holding portion 40 is pulled out. And the pull-out load can be reduced.

  Further, the concave streak portion 41 has the same number of concave portions 41c as the number of lip portions 42 formed. In the example of FIG. 1, three concave portions 41c are provided corresponding to the three lip portions 42. The recessed portion 41c may be annularly provided in the circumferential direction similarly to the lip portion 42, but may be formed discontinuously at appropriate intervals. Since the depressions 41c are provided corresponding to the number of the lips 42 in this manner, an excessive increase in the surface pressure due to the increase in the lips 42 can be suppressed. In addition, since the plurality of lip portions 42 are provided, even when the second pipe 2 is inclined and eccentric, the second holding portion 40 can follow and secure the seal surface pressure. Further, since the recesses 41c are provided for the individual lip portions 42, the contact area when the reinforcing ring 4 is assembled to the concave streak portion 41 is reduced, and the assemblability can be improved.

The lip portions 42, 42, 42 provided on the second holding portion 40 are formed at a fixed distance (interval). The protrusion amount of the lip portions 42, 42, 42 is larger than the distance between the adjacent lip portions 42, 42. The lip portion 42 is configured to elastically contact the second pipe 2 with an interference, and the distance between the adjacent lip portions 42 is greater than the interference of the lip portion 42.
Although the second pipe 2 may vibrate or may cause thermal swelling of the second pipe 2 depending on the material of the second pipe 2, even in such a case, the plurality of lip portions 42 may be connected to each other as described above. If it is provided, it does not come into contact with the second pipe 2 in the assembled state (see FIG. 3 and the like), follows the movement of the second pipe 2, and can maintain the sealing property. Further, since the adjacent lip portions 42 do not contact each other in the assembled state to the second pipe 2, the lip reaction force is excessive due to the mutual fixing of the lip portions 42 (there is no sticking to the lip portions 42, 42). Thus, the insertion and withdrawal loads can be prevented from increasing without improving the insertion / extraction performance.

Subsequently, a procedure for connecting the first pipe 1 and the second pipe 2 in the through hole 10 using the connecting member 3 configured as described above will be described with reference to FIGS. 4 and 5.
<Connection procedure>
First, the reinforcing ring 4 is fitted and accommodated in the connecting member 3 in advance in the concave streak portion 41 of the second holding portion 40. At this time, since the concave portion 41c is formed in the concave streak portion 41 in which the reinforcing ring 4 is accommodated, the contact surface of the reinforcing ring 4 is reduced, the resistance due to friction is reduced, and the reinforcing ring 4 is easily assembled.
Next, as shown in FIG. 4, the first holding portion 30 of the connection member 3 is fitted into the recess 11 of the first pipe 1, and the connection member 3 is assembled to the first pipe 1. During this assembling, the inner peripheral lip portion 32 is elastically deformed so as to be inclined obliquely from the bottom portion 11c toward the opening portion 11d.

  Then, the connection member 3 and subsequently the first pipe 1 are inserted into the through hole 10 of the wall body 101 from the outside (see the direction of the white arrow in FIG. 4). The other end 3 b of the connection member 3 reaches the connection end 2 a of the second pipe 2, and first, the top of the projection 43 elastically contacts the front side 2 ab of the second pipe 2. The front side portion 2ab is formed so as to be smaller in diameter than the other portion of the second pipe 2 so as to gradually increase in diameter, so that the protrusion 43 inclined in the opposite direction to the insertion direction is smoothly elastically deformed. I do. Then, the lip portion 42 arranged on the other end 3b side elastically contacts the outer peripheral surface 2aa of the second pipe 2 and is elastically deformed while being compressed, so as to cover the second pipe 2 in an obliquely inclined state. Be fitted. At this time, when the axis (L1, L2) of the first pipe 1 and the second pipe 2 to be inserted deviates from the axis (L) of the through-hole 10, the outer peripheral projection 51 becomes the inner peripheral surface of the through-hole 10. 10a, the eccentricity of the first pipe 1 and the second pipe 2 can be prevented, and the influence of the outer peripheral lip portion 31 on the seal surface pressure can be reduced. The outer peripheral projections 51 are arranged on the side of the second holding section 40 of the outer peripheral lip 31 and are arranged on the opposite side to the direction in which the outer peripheral lip 31 falls down, so they do not contact each other. Further, since the outer peripheral projection 51 is arranged on the first holding portion 30 side of the connecting portion 50, the outer projection 51 has a structure in which the outer peripheral projection 51 surely contacts the inner peripheral surface 10 a of the through hole 10. Further, the outer peripheral projection 51 has an effect of removing foreign matter on the inner peripheral surface 10 a of the through hole 10 when the connecting member 3 is inserted, and has a structure in which foreign matter does not bite into the contact surface of the outer peripheral lip portion 31.

Then, as shown in FIG. 4, the connecting member 3 is inserted toward the second pipe 2 until the flange 12 of the first pipe 1 comes into contact with the wall body 101. Then, the outer peripheral lip portion 31 elastically contacts the inner peripheral surface 10 a of the through hole 10. At this time, since the inner seal area S1 and the outer seal area S2 are provided at positions that do not overlap in the radial direction, an increase in insertion load can be prevented, and assemblability can be improved. Also, even when the axis L1 of the first pipe 1 and the axis L of the through hole 10 are shifted and eccentric, the eccentricity is provided because the inner seal area S1 and the outer seal area S2 do not overlap in the radial direction. The influence on the surface pressure fluctuation and the internal stress of the inner and outer seal regions S1 and S2 at the time is small, and a stable sealing property can be maintained. Also, at this time, since the connecting portion 50 has elasticity and can be displaced in the radial direction, even if there is some misalignment between the axis L of the through-hole 10 and the axis L2 of the second pipe 2. Is absorbed by the elastic deformation of the connecting portion 50. In particular, since the connecting portion 50 has a tapered shape, the eccentric displacement can be effectively absorbed in combination with the connecting portion 50 itself being made of an elastic body. Furthermore, since the outer peripheral lip portion 31 has the bent portion 31b, when the outer peripheral lip portion 31 is elastically contacted with the inner peripheral surface 10a of the through hole 10, the outer peripheral lip portion 31 is bent so as to be sharply bent with the bent portion 31b as a bending point. it can. Thereby, the insertion load when inserting the first pipe 1 into the through hole 10 can be reduced, and the insertion performance can be improved.
Finally, when the flange 12 of the first pipe 1 is fixed to the wall body 101 by the fixture, the connection of the two pipes 1 and 2 is completed.

  In the connection state shown in FIG. 4, the outer fitting portion of the first holding portion 30 with respect to the first pipe 1 and the outer fitting portion of the second holding portion 40 with respect to the second pipe 2 each have an annular inner peripheral lip portion 32, Since the lip portion 42 is interposed in a compressed state, a connection structure having a high sealing property can be obtained, and the refrigerant can flow between the first pipe 1 and the second pipe 2 via the connection member 3. In addition, since the annular outer lip portion 31 is interposed between the first holding portion 30 and the through hole 10 in a compressed state, the inside and the outside of the inverter case 100 through the through hole 10 are sealed, and from outside through the through hole 10. It is possible to prevent dust and the like from entering the inverter case 100.

Next, with reference to FIGS. 4 and 5, a description will be given of a drawing procedure when the first pipe 1 connected as described above is drawn.
<How to pull out>
First, the fixture that is inserted into the insertion hole of the flange portion 12 of the first pipe 1 and that fixes the first pipe 1 to the wall body 101 is removed, and the flange portion 12 and the like of the first pipe 1 are grasped and the second pipe 2 is removed. A force is applied in the direction of pulling apart, that is, the pulling direction. Then, the lip portion 42, the protruding portion 43, and the outer peripheral lip portion 31 slide along the inner peripheral surface 10a of the second pipe 2 or the through hole 10 in a state where the lip portion 42, the protruding portion 43, and the outer lip portion 31 are inclined in the anti-insertion direction, as shown in FIG. The member 3 is detached from the second pipe 2, and the connection member 3 together with the first pipe 1 can be smoothly pulled out from the second pipe 2. At this time, since the concave portion 41 is provided with the concave portion 41c, the inversion of the lip portion 42 at the time of pulling out is suppressed, and an increase in the pulling load due to the inversion of the lip portion 42 can be prevented. Also, as shown in FIG. 5, even when the lip portion 42, the protruding portion 43, and the outer lip portion 31 are stuck to the second pipe 2 or the inner peripheral surface 10 a of the through hole 10 and are turned over, the concave streak portion 41 has a concave portion. Since 41c is provided and the contact surface with the reinforcing ring 4 is small, the pulling load can be reduced.
Then, in the above-described state, if a force is applied in the pulling direction as it is, the connecting member 3 is separated from the second pipe 2, and the connecting member 3 together with the first pipe 1 is smoothly pulled out from the second pipe 2. Can be.

  In the above-described embodiment, a pipe connection structure for connecting the second pipe 2 provided inside the automobile inverter case 100 and the first pipe 1 provided outside the inverter case 100 by the connection member 3, and An example in which the present invention is applied to the connecting member 3 used in this case has been described. In the through hole of the wall, the first pipe and the second pipe, which are arranged to face each other while being separated in the axial direction, are connected via the connecting member. If it is a piping connection structure, it can be similarly applied to other piping connection structures. The configuration of the connection member 3 is also an example, and is not limited to the illustrated example. The lip portion 42, the protrusion 43, the outer lip portion 31, the inner lip portion 32, the inner protrusion 33, and the outer protrusion. The number and shape (projection amount, projection width, and the like) of the portions 51 are not limited to the illustrated example. Although not shown, for example, the configuration of the contact portion 41ba and the recess 41c provided in the second holding portion 40 is not limited to the illustrated example, and the formation area of the contact portion 41ba and the recess 41c is large or small. Alternatively, the number of lip portions 42 may not be equal to the number of lip portions 42 formed.

REFERENCE SIGNS LIST 100 inverter case 101 wall 10 through hole 10 a inner peripheral surface 1 first piping 2 second piping 3 connecting member 30 first holding portion 30 b outer peripheral surface 31 outer peripheral lip portion 40 second holding portion 50 connecting portion 51 outer peripheral projection

Claims (6)

In the through hole of the wall, a pipe connection structure for connecting the first pipe and the second pipe, which are disposed to face each other in a state of being separated in the axial direction, via a connection member,
A first holding portion externally fitted to the first pipe and internally fitted into the through hole, a second holding portion externally fitted to the second pipe, and the first holding portion; A cylindrical body having a connecting portion that connects the second holding portion;
On the outer peripheral surface of the first holding portion, there is provided an outer peripheral lip portion which elastically contacts the inner peripheral surface of the through-hole with an interference with bending deformation,
A piping connection structure, wherein an outer peripheral projection is provided on the second holding portion side of the outer peripheral lip portion so as to approach or contact the inner peripheral surface of the through hole. The piping connection structure according to claim 1,
The piping connection structure, wherein the outer peripheral projection is provided on a side of the first holding portion of the connecting portion. In the pipe connection structure according to claim 1 or 2,
The pipe connection structure, wherein the outer peripheral protrusions are formed continuously or at appropriate intervals along a circumferential direction. In the pipe connection structure according to any one of claims 1 to 3,
The pipe connection structure, wherein the connection portion is formed to be inclined with respect to an axis of the connection member. In the pipe connection structure according to any one of claims 1 to 4,
A pipe connection structure, wherein a plurality of annular lips for sealing the outer peripheral faces of the first pipe and the second pipe are provided on inner peripheral surfaces of the first holding section and the second holding section. . It is a connection member used for the piping connection structure according to any one of claims 1 to 5,
A first holding portion attached to a connection end of the first pipe, a second holding portion attached to a connection end of the second pipe, and connecting the first holding portion and the second holding portion; A connecting member having an elastically deformable connecting portion.

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