JP4971889B2 - Pipe fitting - Google Patents

Description

  The present invention relates to a joint structure that interconnects a downstream exhaust pipe and an upstream exhaust pipe that form an exhaust passage or the like from a vehicle engine, and more specifically, relatively connects one pipe and the other pipe. The present invention relates to a pipe joint that is swingably connected.

  In general, in an exhaust system of a vehicle engine, an exhaust manifold (upstream exhaust pipe) connected to an exhaust port of the engine and an exhaust pipe on the downstream side thereof are connected to each other via a pipe joint.

This type of pipe joint has a spherical joint structure in many cases, and by allowing relative swinging between the exhaust manifold and the exhaust pipe, vibration caused by exhaust pulsation flowing in the exhaust system and road surface It absorbs and reduces vibrations caused by shock from the vehicle and bending stresses caused by various inertial forces associated with vehicle travel. A conventional pipe joint of this type includes a seat body having a spherical concave surface fixed to an end portion of one pipe, and a seal body having a spherical convex surface fixed to an end portion of the other pipe. The concave surface of the seat body and the convex surface of the seal body are slidably connected to each other so as to be able to swing relative to each other (for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-41932

  However, in the conventional pipe joint described above, since the convex surface of the seal body is in pressure contact with the concave surface of the seat body, there is sufficient friction between the seat body and the seal body due to the presence of friction between both surfaces. The mobility cannot be obtained. For this reason, the minute vibration of the exhaust pipe could not be absorbed. In addition, this vibration may cause an abnormal sound (stagnation sound).

  Therefore, the problem to be solved by the present invention is to provide a pipe joint having a novel structure capable of effectively absorbing minute vibrations at a level that could not be absorbed by a pipe joint having a conventional spherical joint structure. There is.

  The pipe joint of the present invention is configured as follows.

[Configuration 1]
In a pipe joint for connecting one pipe and the other pipe so as to be able to swing relative to each other, the annular first pipe is fixed to the outer peripheral surface of the one pipe and has a partially concave spherical surface that is widened and opened toward the other pipe. An annular second seat having a partially convex spherical surface that is fixed to the outer peripheral surface of one seat and the other tube, has a reduced diameter on the one tube side, and is provided to face the partially concave spherical surface A plurality of rigid spheres of the same diameter sandwiched between the partially concave spherical surface and the partially convex spherical surface, and the first seat and the partial seat while locally contacting the partially concave spherical surface and the partially convex spherical surface An annular member that seals between the second seat and the entire circumference, and holds the plurality of rigid spheres together while keeping a positional relationship between the rigid spheres in the circumferential direction constant, and the first seat And a biasing mechanism for biasing the second seat body toward each other in the tube axis direction. .

  The pipe joint elastically urges and connects one pipe and the other pipe in a direction in which the pipes approach each other in the axial direction, and connects the annular member to the partially concave spherical surface of the first seat and the second seat. Are simultaneously pressed against the partially convex spherical surface to seal the connecting portion of both pipes. Then, the relative swinging of both pipes is allowed by allowing both the seats and the ring member to slide. At this time, the ring member seals between the two seats over the entire circumference while being locally (linearly or strip-shaped) in contact with the partially concave spherical surface of the first seat and the partially convex spherical surface of the second seat. To do. Therefore, it is possible to absorb a smaller amount of vibration as compared with the conventional pipe joint in which the partially concave spherical surface of the seat body is almost entirely in surface contact with the seal body. Arranged in a state where a plurality of rigid spheres are sandwiched between the partially concave spherical surface of the first seat and the partially convex spherical surface of the second seat and the positional relationship between the rigid spheres in the circumferential direction of the seat is kept constant. By doing so, the mutual interval between the partially concave spherical surface and the partially convex spherical surface is always kept constant. That is, the distance between the partially concave spherical surface and the partially convex spherical surface is kept at a distance corresponding to the diameter of the hard sphere. Since the pressure (contact pressure) between the 0009 seat and the annular member is always kept constant, the sealing performance between the two seats by the annular member is always kept stable. Since the frictional force between the two seats and the rigid sphere is extremely smaller than the frictional force between the two seats and the ring member, the presence of the rigid sphere does not impair the relative swingability of the two seats.

[Configuration 2]
Assuming Configuration 1, the ring member is a spherical belt-shaped seal body having a partially concave spherical inner peripheral surface facing the partially convex spherical surface and a partially convex spherical outer peripheral surface facing the partially concave spherical surface. The annular projection that contacts the partial concave spherical surface over the entire circumference, the annular projection that contacts the partial convex spherical surface over the entire circumference, and the seal to hold the rigid sphere in the accommodated state. A through hole formed by penetrating the body in the direction between the inner and outer peripheral surfaces thereof, and the rigid sphere partially protrudes from the inner and outer peripheral surfaces of the seal body while being accommodated in the through hole. A pipe joint characterized by that.

  In this pipe joint, an annular protrusion formed on the inner peripheral surface of a ball-shaped seal body that is an annular member is brought into contact with a partially convex spherical surface, and the annular protrusion formed on the outer peripheral surface of the seal body is partially The concave spherical surface is brought into contact to seal between the two seats. The distance between the partially concave spherical surface and the partially convex spherical surface is always kept constant by the rigid sphere held in the through hole of the seal body.

[Configuration 3]
Assuming Configuration 1, the annular member includes a rigid sphere holding portion that collectively holds the plurality of rigid spheres, and a first seal that is located on a smaller diameter side of the annular member than a formation position of the rigid sphere holding portion. And a second seal portion located on the larger diameter side of the annular member than the formation position of the rigid sphere holding portion.

  This pipe joint seals two places between both seats by the 1st seal part and the 2nd seal part. Compared with the case where only one place is sealed, the sealing performance can be further improved.

[Configuration 4]
The said ring member is a pipe joint which is a substantially frustum-shaped or substantially spherical band-shaped metal integrally molded product molded so as to have resilience and resilience against deformation due to external force.

  The number of parts of the pipe joint can be reduced because the annular member is a metal integrally formed product.

[Configuration 5]
Assuming Configuration 1, the annular member is formed by overlapping an annular outer metal member facing the partially concave spherical surface and an annular inner metal member facing the partially convex spherical surface and providing a bending margin at the small diameter side end. In addition, it is hermetically bonded to each other and seals between the first seat and the second seat over the entire circumference while locally contacting the partially concave spherical surface and the partially convex spherical surface. An annular seal portion formed to hold, and a rigid sphere holding portion that holds the plurality of rigid spheres in a lump while keeping a positional relationship between the rigid spheres in a circumferential direction constant. By bending the bending margin portion of the outer metal member so as to have resilience and restoring properties and bringing the partial concave spherical surface into contact with the entire concave spherical surface, and bending the bending margin portion of the inner member. Rebound resilience The partial convex spherical surface in contact over the entire circumference, characterized by being configured, the pipe joint.

  In this pipe joint, the seal portion of the ring member is constituted by a bending margin portion of the outer metal member and a bending margin portion of the inner metal member. Then, the bend allowance portion of the outer metal member is brought into contact with the partial concave spherical surface over the entire circumference, and the bend allowance portion of the inner metal member is brought into contact with the partial convex spherical surface over the entire circumference so that the gap between the both seats is reached. Seal. The bending margin portion of the outer metal member locally contacts the partially concave spherical surface. The portion of the bending margin of the inner metal member locally contacts the partially convex spherical surface. The rigid sphere and the seal portion are slidable in the relative swinging direction with respect to the partially concave spherical surface and the partially convex spherical surface, thereby allowing relative swinging of both the tubes. The annular member is easy to manufacture because the outer metal member and the inner metal member are respectively bent, and the two members are overlapped and hermetically joined leaving a portion of the bending allowance.

[Configuration 6]
On the premise of Configuration 4, one of the outer metal member and the inner metal member is formed only from a joint portion that is airtightly joined to the other member so as to border the bending margin and the bending margin. A first metal member and a second metal member that constitutes the rigid sphere holding portion together with the other member, and the other member includes a bridge portion that connects the seal portion and the rigid sphere holding portion. A pipe joint characterized in that a notch hole is formed leaving a hole.

  This pipe joint has a notched hole formed so as to leave a bridge part connecting the seal part and the rigid sphere holding part, thereby reducing the weight of the annular member and providing a rigid body compared to the pipe joint of Configuration 5. The connecting portion between the ball holding portion and the seal portion, that is, the bridge portion can be provided with flexibility to enhance the sealing performance between the two seats by the seal portion. In other words, the rigid ball holding portion and the seal portion are flexibly connected (the rigidity of the connection portion is relatively small), thereby improving the followability of the seal portion with respect to the swinging motion between the two seats, and stable. Seal performance can be secured.

[Configuration 7]
A pipe joint characterized in that a lubricant layer is formed on a contact portion between the partial concave spherical surface and the partial convex spherical surface of the annular member on the premise of any one of configurations 1 to 6.

  In this pipe joint, it is possible to improve the slidability of the annular member with respect to both seats and to absorb more minute vibrations.

[Configuration 8]
A pipe joint comprising a holding mechanism for holding the position of the annular member with respect to the first seat body or the second seat body on the premise of any one of configurations 1 to 7.

  In this pipe joint, since the position of the ring member relative to the first seat body or the second seat body is held by the holding mechanism, positioning of the ring member can be facilitated in the manufacturing stage.

[Configuration 9]
A pipe joint characterized in that the rigid sphere is a silicon nitride ceramic ball on the premise of any one of configurations 1 to 8.

  In this pipe joint, since the rigid sphere is a silicon nitride ceramic ball, problems such as micropits caused by sliding with the seat can be prevented, and performance can be maintained over a long period of time. it can.

[Configuration 10]
A pipe joint comprising three or more of the hard spheres on the premise of any one of configurations 1 to 9.

  Since this pipe joint is provided with three or more hard spheres, it is possible to stably allow relative swinging in any direction.

  According to the pipe joint having the above-described structure, it is possible to absorb minute vibrations as compared with a pipe joint having a conventional structure in which almost the entire concave spherical surface of the seat body is in contact with the seal body. It is possible to suppress the occurrence of squeaking noise.

  Hereinafter, the present invention will be described in detail according to embodiments with reference to the drawings.

[First embodiment]
FIG. 1 is a cross-sectional view of an essential part of a first embodiment of a pipe joint according to the present invention.

  The pipe joint 100 includes an annular first seat 110 provided at an end of an upstream exhaust pipe (one pipe) 201 and an annular provided at an end of a downstream exhaust pipe (other pipe) 202. The second seat 120, a plurality (four in this example) of rigid balls 150 sandwiched between the two seats 110, 120, and the ring mounted between the both seats 110, 120. A member 130 and an urging mechanism 140 that elastically urges the seats 110 and 120 toward each other are provided. The exhaust pipes 201 and 202 constitute part of an exhaust system connected to the engine. Further, in this example, the end of the downstream exhaust pipe 202 has an enlarged diameter, and is configured to accommodate the end of the upstream exhaust pipe 201.

  The first seat 110 is welded and fixed to the outer peripheral surface of the end of the upstream side exhaust pipe 201 in an airtight manner over the entire circumference. The first seat body 110 has a partially concave spherical surface 111 whose diameter is increased toward the downstream side exhaust pipe 202 side. The first seat body 110 has a flange portion 114 formed so that the open end portion of the partially concave spherical surface 111 is folded outward. The flange portion 114 is provided at two places in the circumferential direction. Bolt fixing holes 113 are formed in the flange portions 114 at one location. Further, the first seat body has a cover portion 117 extending from the first seat body. The cover part 117 is provided in order to prevent foreign matters such as water and mud from entering the space formed by the first seat body 110 and the second seat body 120, and its end portion is relatively It is provided so as to cover the entire periphery of the end of the second seat body 120 with a gap for allowing rocking.

  The second seat 120 is welded and fixed to the outer peripheral surface of the end of the downstream side exhaust pipe 202 in an airtight manner over the entire circumference. The second seat 120 has a spherical partially convex spherical surface 121 corresponding to the partially concave spherical surface 111 and projecting (reducing diameter) toward the upstream exhaust pipe 201. The second seat body 120 has a flange portion 124 formed to face the flange portion 114 of the first seat body 110. A bolt insertion hole 123 is formed in the second flange portion 124 so as to correspond to the bolt fixing hole 113 of the first flange portion 114.

  The rigid sphere 150 has four rigid bodies sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120 and in the circumferential direction of the both seats 110 and 120. The balls 150 are arranged in a state where the positional relationship between the balls 150 is kept constant. These four hard spheres 150 have the same diameter.

  The ring member 130 is between the first seat 110 and the second seat 120 while locally contacting the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120. It is a spherical belt-like sealing body that seals over the entire circumference. The ring member 130 includes a partially concave spherical inner peripheral surface 130a facing the partially convex spherical surface 121, a partially convex spherical outer peripheral surface 130b facing the partially concave spherical surface 111, a small-diameter-side annular end surface 130c, and a large diameter. Side annular end face 130d.

  The annular member 130 includes a first seal portion 130A that seals between both seats 110 and 120 in the vicinity of the small-diameter side annular end surface 130c, and a space between both seats 110 and 120 in the vicinity of the large-diameter side annular end surface 130d. It has the 2nd seal | sticker part 130B to seal. The first seal portion 130A includes an annular protrusion 131b formed along the small diameter side opening edge of the inner peripheral surface 130a and an annular protrusion 132b formed along the small diameter side opening edge of the outer peripheral surface 130b. Is done. The second seal portion 130B includes an annular protrusion 132a formed along the large-diameter opening edge of the inner peripheral surface 130a, and an annular protrusion 131a formed along the large-diameter opening edge of the outer peripheral surface 130b. Consists of. The inner protrusions 132a and 132b of the seal portions 130A and 130B are in contact with the partially convex spherical surface 121, and the outer protrusions 131a and 131b are in contact with the partially concave spherical surface 111 over the entire circumference. Between 110 and 120 is sealed.

  The ring member 130 has four through holes 135 for holding the rigid sphere 150 between the first seal portion 130A and the second seal portion 130B. The through holes 135 are formed at equal intervals in the circumferential direction of the ring member 130. The through-hole 135 has a partially spherical inner surface formed by penetrating the annular member 130 in the direction between the inner and outer peripheral surfaces to hold the rigid sphere 150 in the accommodated state. The rigid sphere 150 partially protrudes from the inner and outer peripheral surfaces 130 a and 130 b of the ring member 130 in a state of being accommodated in the through hole 135. The opening diameter on the inner peripheral surface 130 a side of the through hole 135 is selected to be smaller than the diameter of the rigid sphere 150. On the other hand, the opening diameter on the outer peripheral surface 130 b side of the through hole 135 is selected to be larger than the diameter of the rigid sphere 150 in order to facilitate mounting of the rigid sphere 150 in the through hole 135.

  In addition, the annular member 130 is forcibly attached to the first seat 110 by the holding member 170 (elastic body) in order to maintain a relative positional relationship with the first seat 110 (that is, the upstream side exhaust pipe 201). It is pressed. Providing the holding member 170 facilitates positioning of the annular member 130 in the production stage of the pipe joint 100, and prevents excessive movement of the annular member 130 in the axial direction when the pipe joint 100 is used. Can be prevented. The holding member 170 is made by bending a stainless steel rod-like member, and has sufficient rigidity and elasticity to prevent the excessive movement of the annular member 130 and return it to a fixed position. The both ends of the holding member 170 of this example are engaged with the holding member engaging holes 116 provided in the cover portion 117, and the intermediate portion presses the large-diameter-side annular end surface 130 d of the ring member 130. ing.

  The urging mechanism 140 includes a stepped bolt 141, a nut 144, and a coil spring (elastic body) 143. The stepped bolt 141 is inserted into the bolt insertion hole 123 of the flange portion 124 from the downstream side exhaust pipe 202 side, and the screw portion formed at the tip portion is inserted into the bolt fixing hole 113 of the first flange portion 114 so as not to be detached. The upstream exhaust pipe 201 and the downstream exhaust pipe 202 are connected to each other by being fixed to the nut 144. Further, the bolt insertion hole 123 is formed with a margin with respect to the diameter of the stepped bolt 141 and has a structure that allows relative swinging of the upstream side exhaust pipe 201 and the downstream side exhaust pipe 202. The coil spring 143 is provided so as to surround the stepped bolt 141.

  The pipe joint 100 configured as described above elastically biases and connects the upstream exhaust pipe 201 and the downstream exhaust pipe 202 in the direction in which the upstream exhaust pipe 201 and the downstream exhaust pipe 202 approach each other. The partial concave spherical surface 111 of the first seat body 110 and the partial convex spherical surface 121 of the second seat body 120 are simultaneously pressed into contact with each other, and the connecting portions of both the tubes 201 and 202 are sealed. Then, both the seats 110, 120 and the ring member 130 are slidable, thereby allowing the relative swinging of both the tubes 201, 202. At this time, the annular member 130 is locally in contact with the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and extends between the seats 110 and 120 over the entire circumference. And seal. Therefore, it is possible to absorb a smaller amount of vibration as compared with the conventional pipe joint in which the partially concave spherical surface of the seat body is almost entirely in surface contact with the seal body.

  More specifically, the annular member 130 seals between the seats 110 and 120 by two seal portions 130A and 130B formed on the small diameter side and the large diameter side from the holding position of the rigid sphere 150. The first seal portion 130A has an annular protrusion 132b formed along the small-diameter side opening edge of the inner peripheral surface 130a in contact with the partial convex spherical surface 121 of the second seat 120 over the entire periphery, and the outer peripheral surface. An annular protrusion 131b formed along the small-diameter-side opening edge of 130b is brought into contact with the partial concave spherical surface 111 of the first seat body 110 over the entire circumference, so that both seats are provided in the vicinity of the small-diameter-side annular end surface 130c. Seal between the bodies 110, 120. The second seal portion 130B has an annular protrusion 132a formed along the large-diameter opening edge of the inner peripheral surface 130a in contact with the partial convex spherical surface 121 of the second seat 120 over the entire periphery. An annular protrusion 131a formed along the large-diameter side opening edge of the surface 130b is brought into contact with the partial concave spherical surface 111 of the first seat body 110 over the entire circumference, thereby bringing the annular protrusion 131a in the vicinity of the large-diameter annular end surface 130d. To seal between the seats 110 and 120. Thus, by sealing the two places between the both seats 110 and 120 over the entire circumference, the sealing performance can be further improved as compared with the case where only one place is sealed.

  Further, in this pipe joint 100, the four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and both the seats 110, 120. Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. That is, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is kept at a distance corresponding to the diameter of the rigid sphere 150. As a result, the pressure (contact pressure) that acts between the seats 110 and 120 and the ring member 130 that is the seal body is always kept constant, so that the sealability between the seats 110 and 120 by the ring member 130 is maintained. Is always kept stable. Since the frictional force between the two seats 110, 120 and the rigid sphere 150 is extremely smaller than the frictional force between the two seats 110, 120 and the ring member 130, the presence of the four rigid spheres 150 allows the two seats 110 to be present. , 120 is not impaired.

  Therefore, according to this pipe joint 100, even if a minute vibration is generated in one of the upstream exhaust pipe 201 and the downstream exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed.

[Second embodiment]
FIG. 2 is a cross-sectional view of the main part showing a second embodiment of the pipe joint according to the present invention. Moreover, the same code | symbol is attached | subjected regarding the member of the name which is common with the pipe joint 100 of FIG.

  In this pipe joint 200, since the configuration other than the ring member 230 is the same as that of the pipe joint 100, the description thereof is omitted.

  The ring member 230 is circularly mounted between the both seats 110 and 120. The annular member 230 is between the first seat 110 and the second seat 120 while locally contacting the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120. It is a seal body that seals over the entire circumference, and includes a spherical belt-shaped main body and first and second annular seal members 237a and 237b assembled to the main body. The first annular seal member 237 b is embedded along the small-diameter side opening edge of the inner peripheral surface 230 a of the ring member 230. The second annular seal member 237 a is embedded along the large-diameter side opening edge of the inner peripheral surface 230 a of the ring member 230.

  The ring member 230 includes a partially concave spherical inner peripheral surface 230a facing the partially convex spherical surface 121, a partially convex spherical outer peripheral surface 230b facing the partially concave spherical surface 111, a small-diameter-side annular end surface 230c, and a large diameter. Side annular end face 230d.

  The annular member 230 includes a first seal portion 230A that seals between the seats 110 and 120 in the vicinity of the small-diameter side annular end surface 230c, and a space between the seats 110 and 120 in the vicinity of the large-diameter side annular end surface 230d. And a second seal portion 230B for sealing.

  The first seal portion 230A includes a first annular seal member 237b and an annular protrusion 231b formed along the small-diameter side opening edge of the outer peripheral surface 230b.

  The second seal portion 230B includes a second annular seal member 237a and an annular protrusion 231a formed along the large-diameter opening edge of the outer peripheral surface 230b.

  The annular seal members 237a and 237b are fitted into annular grooves 236a and 236b formed coaxially on the small diameter side and the large diameter side of the inner peripheral surface 230a of the ring member 230, respectively, so that the inner peripheral surface 230a portion is fitted. Most of the material is held in an embedded state, and a part thereof (inner peripheral side portion) protrudes from the inner peripheral surface 230a.

  The projections 231a and 231b on the outer side of the seal body 230 are on the partially concave spherical surface 111 of the first seat body 110, and the inner peripheral surfaces of both annular seal members 237a and 237b are on the partially convex spherical surface 121 of the second seat body 120, respectively. In this way, the space between both seats 110 and 120 is sealed.

  The ring member 230 has four through holes 235 for holding the rigid sphere 150 between the first seal portion 230A and the second seal portion 230B. The through holes 235 are formed at equal intervals in the circumferential direction of the ring member 230. The through-hole 235 has a partially spherical inner surface formed by penetrating the annular member 230 in the direction between the inner and outer peripheral surfaces so as to hold the rigid sphere 150 in the accommodated state. The rigid sphere 150 partially protrudes from the inner and outer peripheral surfaces 230a and 230b of the ring member 230 in a state of being accommodated in the through hole 235. The opening diameter of the through hole 235 on the inner peripheral surface 230 a side is selected to be smaller than the diameter of the rigid sphere 150. On the other hand, the opening diameter on the outer peripheral surface 230b side of the through hole 235 is selected to be larger than the diameter of the rigid sphere 150 so as to facilitate the mounting of the rigid sphere 150 in the through hole 235.

  The pipe joint 200 configured as described above elastically biases and connects the upstream exhaust pipe 201 and the downstream exhaust pipe 202 in the direction in which the upstream exhaust pipe 201 and the downstream exhaust pipe 202 approach each other. The partial concave spherical surface 111 of the first seat body 110 and the partial convex spherical surface 121 of the second seat body 120 are simultaneously pressed into contact with each other, and the connecting portions of both the tubes 201 and 202 are sealed. Then, both the seats 110, 120 and the ring member 130 are slidable, thereby allowing the relative swinging of both the tubes 201, 202. At this time, the annular member 230 seals between the seats 110 over the entire circumference while locally contacting the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120. To do. Therefore, it is possible to absorb a smaller amount of vibration as compared with the conventional pipe joint in which the partially concave spherical surface of the seat body is almost entirely in surface contact with the seal body.

  More specifically, the annular member 230 seals between the seats 110 and 120 by two seal portions 230A and 230B formed on the small diameter side and the large diameter side from the holding position of the rigid sphere 150. The first seal portion 230A makes the annular seal member 237b provided along the small-diameter side opening edge of the inner peripheral surface 230a contact the partial convex spherical surface 121 of the second seat 120 over the entire periphery, and the outer peripheral surface. The annular protrusion 231b formed along the small-diameter side opening edge of 230b is brought into contact with the partial concave spherical surface 111 of the first seat body 110 over the entire circumference, so that both seats are provided in the vicinity of the small-diameter annular end surface 230c. Seal between the bodies 110, 120. The second seal portion 230B makes the annular seal member 237a provided along the large-diameter opening edge of the inner peripheral surface 230a contact the partial convex spherical surface 121 of the second seat 120 over the entire circumference and An annular protrusion 231a formed along the large-diameter side opening edge of the surface 230b is brought into contact with the partially concave spherical surface 111 of the first seat body 110 over the entire circumference, so that it is in the vicinity of the large-diameter-side annular end surface 230d. To seal between the seats 110 and 120. Thus, by sealing the two places between the both seats 110 and 120 over the entire circumference, the sealing performance can be further improved as compared with the case where only one place is sealed.

  Further, in this pipe joint 200, the four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and both the seats 110, 120. Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. That is, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is kept at a distance corresponding to the diameter of the rigid sphere 150. Thereby, since the pressure (contact pressure) which acts between the both seats 110 and 120 and the ring member 230 which is a seal body is always kept constant, the sealing performance between the both seats 110 and 120 by the ring member 230 is maintained. Is always kept stable. Since the frictional force between the two seats 110, 120 and the rigid sphere 150 is extremely smaller than the frictional force between the two seats 110, 120 and the ring member 230, the presence of the four rigid spheres 150 allows the two seats 110 to be present. , 120 is not impaired.

  Therefore, according to this pipe joint 200, even if a minute vibration occurs in one of the upstream exhaust pipe 201 and the downstream exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed. In this pipe joint 200, the ring member 230 is assembled between a spherical belt-like main body having annular projections 231a and 231b for sealing the space between the first seat 110 and the second seat 120. Since the first and second annular seal members 237a and 237b are sealed, when either the main body or the seal members 237a or 237b is worn or damaged first, only that member can be replaced. So it is very economical. Further, by adjusting the thickness of the annular seal members 237a and 237b, the sealing performance and sliding performance of the annular member 230, that is, the contact pressure of the annular member 230 with respect to the both seats 110 and 120 can be easily adjusted. Can do.

[Third embodiment]
FIG. 3 is a cross-sectional view of a main part showing a pipe joint 300 according to the present invention. Moreover, the same code | symbol is attached | subjected regarding the member of the name which is common with the pipe joint 100 of FIG.

  In this pipe joint 300, since the configuration other than the ring member 330 is the same as that of the pipe joint 100, the description thereof is omitted.

  The annular member 330 is annularly mounted between the both seats 110 and 120. The ring member 330 includes a first seal body 334 and a second seal body 331. Both seal bodies 334 and 331 are substantially spherical belt-shaped members having different shapes and dimensions.

  The second seal body 331 includes a partially concave spherical inner peripheral surface 331a facing the second seat 120, a partially convex spherical outer peripheral surface 331b facing the first seat 110, and a small-diameter annular end surface 331c. And a large-diameter-side annular end surface 331d. An annular recess 333 is formed coaxially with the outer peripheral surface 331 b of the first seal body 331.

  The first seal body 334 includes a partially convex spherical outer peripheral surface 334b facing the first seat 110, a partially concave spherical inner peripheral surface 334a facing the outer peripheral surface 331b of the second seal body 331, and a small diameter side. It has an annular end surface 334c and a large-diameter side annular end surface 334d. The first seal body 334 has an inner peripheral portion that fits into the recess 333 of the second seal body 331, and an outer peripheral portion that protrudes from the outer peripheral surface 331 b of the second seal body 331. The small-diameter-side annular end surface 334c and the large-diameter-side annular end surface 334d of the first seal body 334 are slidable with the inner wall of the annular recess 333 of the second seal body 331.

  Elastic members 345 a and 345 b are interposed between the first seal body 334 and the second seal body 331. The elastic members 345a and 345b are mounted on the peripheral surfaces of the end portions on the large diameter side and the small diameter side of the annular recess 333. The first seal body 334 and the second seal body 331 are in pressure contact with the first seat body 110 and the second seat body 120, respectively, by the step force of the elastic members 345a and 345b.

  The annular member 330 includes a first seal portion 330A that seals between the seats 110 and 120 in the vicinity of the small-diameter-side annular end surface 331c, and a space between the seats 110 and 120 in the vicinity of the large-diameter-side annular end surface 331d. It has the 2nd seal | sticker part 330B to seal.

  The first seal portion 330A includes an annular protrusion 332b formed along the small-diameter opening edge of the inner peripheral surface 331a of the second seal body 331, and a small-diameter opening edge of the outer peripheral surface 334b of the first seal body 334. And an annular protrusion 336b formed along the line.

  The second seal portion 330B includes an annular protrusion 332a formed along the large-diameter opening edge of the inner peripheral surface 330a of the second seal body 331, and a large-diameter side opening of the outer peripheral surface 334b of the first seal body 334. And an annular protrusion 336a formed along the edge.

  The protrusions 332a and 332b on the inner side of the second seal body 331 are in contact with the partially convex spherical surface 121, and the protrusions 336a and 336b on the outer side of the first seal body 334 are in contact with the partially concave spherical surface 111, respectively. Thus, the space between both seats 110 and 120 is sealed.

  The ring member 330 has four through holes 339 for holding the rigid sphere 150 between the first seal portion 330A and the second seal portion 330B. The through holes 339 are formed at equal intervals in the circumferential direction of the ring member 330. The through hole 339 has a partially spherical inner surface formed by penetrating the annular member 330 in the direction between the inner and outer peripheral surfaces so as to hold the rigid sphere 150 in the accommodated state. The through-hole 339 in this example includes a through-hole 339a that penetrates the concave portion 333 of the second seal body 331 inward and outward, and a through-hole 339b that communicates with the first seal body 334 inward and outward.

  The rigid sphere 150 partially protrudes from the inner and outer peripheral surfaces 331 a and 334 b of the ring member 330 in a state of being accommodated in the through hole 339. The opening diameter of the through hole 339a on the inner peripheral surface 331a side is selected to be smaller than the diameter of the rigid sphere 150. On the other hand, the opening diameter of the through hole 339b on the outer peripheral surface 334b side is selected to be larger than the diameter of the rigid sphere 150 in order to facilitate the mounting of the rigid sphere 150 into the through hole 339.

  The pipe joint 300 configured as described above elastically biases and connects the upstream exhaust pipe 201 and the downstream exhaust pipe 202 in the direction in which the upstream exhaust pipe 201 and the downstream exhaust pipe 202 approach each other. The partial concave spherical surface 111 of the first seat body 110 and the partial convex spherical surface 121 of the second seat body 120 are simultaneously pressed into contact with each other, and the connecting portions of both the tubes 201 and 202 are sealed. Then, both the seats 110, 120 and the ring member 330 are slidable, thereby allowing the relative swinging of both the tubes 201, 202. At this time, the ring member 330 is locally in contact with the partially concave spherical surface 111 of the first seat body 110 and the partially convex spherical surface 121 of the second seat body 120 and extends between the both seat bodies 110 and 120 over the entire circumference. And seal. Therefore, it is possible to absorb a smaller amount of vibration as compared with the conventional pipe joint in which the partially concave spherical surface of the seat body is almost entirely in surface contact with the seal body.

  More specifically, the annular member 330 seals between the seats 110 and 120 by two seal portions 330A and 330B formed on the small diameter side and the large diameter side from the holding position of the rigid sphere 150. The first seal portion 330A makes an annular protrusion 332b formed along the small-diameter side opening edge of the inner peripheral surface 331a contact the partial convex spherical surface 121 of the second seat 120 over the entire periphery, and the outer peripheral surface. An annular protrusion 336b formed along the small-diameter-side opening edge of 334b is brought into contact with the partial concave spherical surface 111 of the first seat 110 over the entire circumference, so that both seats are provided in the vicinity of the small-diameter-side annular end surface 331c. Seal between the bodies 110, 120. The second seal portion 330B has a projection 332a formed along the large-diameter opening edge of the inner peripheral surface 331a in contact with the partially convex spherical surface 121 of the second seat 120 over the entire circumference, and an outer peripheral surface 334b. An annular protrusion 336a formed along the large-diameter opening edge of the first contact body 110 is brought into contact with the partially concave spherical surface 111 of the first seat body 110 over the entire circumference, so that both are formed in the vicinity of the large-diameter annular end surface 331d. The space between the seats 110 and 120 is sealed. Thus, by sealing the two places between the both seats 110 and 120 over the entire circumference, the sealing performance can be further improved as compared with the case where only one place is sealed.

  Further, in this pipe joint 300, the four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and both the seats 110, 120. Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. That is, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is kept at a distance corresponding to the diameter of the rigid sphere 150. As a result, the pressure (contact pressure) acting between the seats 110 and 120 and the annular member 330 serving as the seal body is always kept constant, so that the sealability between the seats 110 and 120 by the annular member 330 is maintained. Is always kept stable. Since the frictional force between the two seats 110, 120 and the rigid sphere 150 is extremely smaller than the frictional force between the two seats 110, 120 and the ring member 330, the presence of the four rigid spheres 150 allows the two seats 110. , 120 is not impaired.

  Furthermore, in this pipe joint 300, elastic members 345a and 345b are provided between the first seal body 334 and the second seal body 331, and the small-diameter-side annular end surface 334c and the large diameter of the second seal body 331 are provided. Since the side annular end surface 334d is slidable with the inner wall of the annular recess 333 of the second seal body 331, the elastic deformation of the annular member 150 is more easily allowed as compared with the first embodiment. The relative swinging of the tubes 201 and 202 becomes smoother.

  Therefore, according to this pipe joint 300, even if a slight vibration occurs in one of the upstream side exhaust pipe 201 and the downstream side exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed. In this pipe joint 300, the ring member 330 includes a first seal body 334 that seals between the first seat body 110 and a second seal body 331 that seals between the second seat body 120. Therefore, when either of the seal bodies 334 and 331 is worn or damaged first, only that member can be replaced, which is very economical. Further, by adjusting the stepping property of the elastic members 345a and 345b interposed between the both seal bodies 334 and 331, the sealability and slidability of the ring member 330, that is, the ring mount with respect to the both seat bodies 110 and 120 are adjusted. The contact pressure of the member 330 can be easily adjusted.

[Fourth embodiment]
Fig.4 (a) is principal part sectional drawing which shows the pipe joint concerning this invention. FIG.4 (b) is a whole perspective view of the annular member with which the pipe joint shown to (a) is provided. The members having the same names as those of the pipe joint 100 of FIG.

  In this pipe joint 400, the configuration other than the annular member 430 and the biasing mechanism 140 is the same as that of the pipe joint 100.

  The ring member 430 is a metal integral-molded product having a substantially truncated cone shape (substantially spherical belt shape) that is molded so as to have resilience and resilience against deformation caused by external force. The ring member 430 includes a hard sphere holding portion 430A, a first seal portion 430B, a second seal portion 430C, and an arm portion 430D.

  The rigid sphere holding portion 430A includes four rigid sphere holding holes 438 provided at equal intervals in the circumferential direction of the ring member 430. A pair of annular holding pieces 438a and 438b having a bifurcated cross section are formed on the periphery of the rigid sphere holding hole 438 so as to border the rigid sphere holding hole 438. The rigid sphere 150 is held in the rigid sphere holding hole 438 in a state of being fitted in the holding pieces 438a and 438b.

  The first seal portion 430 </ b> B includes an annular elastic portion having a bifurcated cross section that is formed at the small-diameter side opening edge portion of the ring member 430 and is open to the outside. The tip of the elastic portion is in contact with the partial concave spherical surface 111 of the first seat 110 over the entire circumference, and with the partial convex spherical surface 121 of the second seat 120 over the entire circumference. The contact part 432b to be formed is formed. The cross-sectional shape of the contact portions 432a and 432b is substantially circular.

  The second seal portion 430 </ b> C includes an annular elastic portion having a bifurcated cross section that is formed on the large-diameter side opening edge of the ring member 430 and is open to the inside and outside. The tip of the elastic portion is in contact with the partial concave spherical surface 111 of the first seat body 110 over the entire circumference and in contact with the partial convex spherical surface 121 of the second seat body 120 over the entire circumference. The contact part 431b to be formed is formed. The cross-sectional shape of the contact portions 431a and 431b is substantially circular. A lubricant layer is formed on the surfaces of the contact portions 431a, 431b, 432a, and 432b. The lubricant layer has high lubricity with respect to the partially concave spherical surface 111 and the partially convex spherical surface 121. The lubricant layer is formed by a known method such as coating or vapor deposition.

  The arm portion 430D is provided at two locations in the circumferential direction at the end of the large-diameter side of the rigid sphere holding portion 430A in accordance with the positions of both flange portions 114 and 124. An annular bolt insertion portion 430E is formed at the tip of the arm portion 430D, and a stepped bolt 141 is inserted into the bolt insertion portion 430E so as to be capable of relative swinging and sliding.

  The pipe joint 400 configured as described above seals between the seats 110 and 120 by the two seal portions 430B and 430C of the ring member 430. The first seal portion 430B makes the contact portion 432b inside the annular elastic portion formed at the small-diameter side opening edge portion of the ring member 430 contact the partially convex spherical surface 121 of the second seat 120 over the entire circumference. At the same time, the contact portion 432a outside the annular elastic portion is brought into contact with the partial concave spherical surface 111 of the first seat 110 over the entire circumference, thereby sealing between the two seats 110 and 120. The second seal portion 430C contacts the partially convex spherical surface 121 of the second seat 120 over the entire circumference of the contact portion 431b inside the annular elastic portion formed at the large-diameter opening edge of the ring member 430. At the same time, the contact portion 431a outside the annular elastic portion is brought into contact with the partial concave spherical surface 111 of the first seat 110 over the entire circumference, thereby sealing between the two seats 110 and 120. Thus, by sealing the two places between the both seats 110 and 120 over the entire circumference, the sealing performance can be further improved as compared with the case where only one place is sealed.

  Further, in this pipe joint 400, the four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and both the seats 110, 120. Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. That is, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is kept at a distance corresponding to the diameter of the rigid sphere 150. As a result, the pressure (contact pressure) acting between the seats 110 and 120 and the ring member 430 that is the seal body is always kept constant, so that the sealability between the seats 110 and 120 by the ring member 430 is maintained. Is always kept stable. Since the frictional force between the two seats 110 and 120 and the rigid sphere 150 is extremely smaller than the frictional force between the two seats 110 and 120 and the ring member 430, the presence of the four rigid spheres 150 allows the two seats 110. , 120 is not impaired.

  Therefore, according to this pipe joint 400, even if a minute vibration is generated in one of the upstream exhaust pipe 201 and the downstream exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed. Since the ring member 430 is a metal integrally molded product, the number of parts of the pipe joint 100 can be reduced as compared with the first to third embodiments.

[Fifth embodiment]
FIG. 5 is a cross-sectional view of a main part showing a pipe joint 500 according to the present invention. Moreover, the same code | symbol is attached | subjected regarding the member of the name which is common with the pipe joint 100 of FIG.

  The pipe joint 500 includes an annular first seat 110 provided at an end of a downstream exhaust pipe (one pipe) 201 and an annular provided at an end of an upstream exhaust pipe (other pipe) 202. The second seat 120, a plurality of rigid balls 150 sandwiched between the two seats 110, 120, an annular member 530 that is looped between the two seats 110, 120, and both the seats 110, 120. And an urging mechanism 140 that urgently urges them in a direction in which they are brought closer to each other. The exhaust pipes 201 and 202 constitute part of an exhaust system connected to the engine. Further, in this example, the end of the downstream exhaust pipe 201 has an enlarged diameter, and is shaped to accommodate the end of the upstream exhaust pipe 202.

  The first seat 110 is welded and fixed to the outer peripheral surface of the end of the downstream side exhaust pipe 201 in an airtight manner over the entire circumference. The first seat body 110 has a spherical partial concave spherical surface 111 opened to the upstream side exhaust pipe 202 side. The first seat body 110 is a member extending from the partially concave spherical surface 111 and has a flange portion 114 formed so that the open end portion is folded outward. The flange portion 114 is provided at two places in the circumferential direction. Each of the flange portions 114 is formed with a bolt insertion hole 115 at one location.

  The second seat body 120 is welded and fixed to the outer peripheral surface of the end portion of the upstream side exhaust pipe 202 in an airtight manner over the entire circumference. The second seat 120 has a spherical partial convex spherical surface 121 that protrudes toward the downstream side exhaust pipe 201 in correspondence with the partial concave spherical surface 111. The second seat body 120 has a flange portion 124 formed to face the flange portion 114 of the first seat body 110. Bolt fixing holes 125 are formed in the flange portion 124 so as to correspond to the bolt insertion holes 115 of the flange portion 114. Furthermore, the second seat body 120 has a cover portion 127 extending from the second seat body 120. The cover portion 127 is provided in order to prevent foreign matter such as water and mud from entering the space formed by the first seat body 110 and the second seat body 120, and its end portion is relatively It is provided so as to cover the entire end of the first seat body 110 with a gap for allowing swinging.

  The annular member 530 overlaps the annular outer metal member 530 a facing the partially concave spherical surface 111 of the first seat 110 and the annular inner metal member 530 b facing the partially convex spherical surface 121 of the second seat 120. The end portions on the small diameter side are hermetically joined to each other leaving bending margins 531a and 531b. The annular member 530 is formed so as to seal the entire circumference between the first seat 110 and the second seat 120 while locally contacting the partially concave spherical surface 111 and the partially convex spherical surface 121. An annular seal portion 530A, and a rigid sphere holding portion 530B that collectively holds the plurality of rigid spheres 150 while maintaining a constant positional relationship between the rigid spheres in the circumferential direction.

  The seal portion 530A has a rebound restoring property by bending a portion of the bending allowance 531a of the outer metal member 530a so as to be brought into contact with the partial concave spherical surface 111 over the entire circumference and the bending allowance 531b of the inner metal member 530b. The part is bent so as to have a resilience and restoration property, and is brought into contact with the partial convex spherical surface 121 over the entire circumference.

  The bending margin 531a of the outer metal member 530a is formed with an annular contact portion 532a that contacts the partially concave spherical surface 111 so as to border the inner edge portion thereof. The bending margin 531b of the inner metal member 530b is formed with an annular contact portion 532b that contacts the partially convex spherical surface 121 so as to border the inner edge portion thereof. The cross-sectional shape of the contact portions 532a and 532b is a substantially arc shape. Further, a lubricant layer is formed on the contact portions 532a and 532b.

  The rigid sphere holding portion 530B includes four rigid sphere holding holes 535 provided at equal intervals in the circumferential direction of the ring member 530. The rigid sphere holding hole 535 is formed by penetrating the outer metal member 530a and the inner metal member 530b to form through holes 535a and 535b.

  The inner edge portion of the through hole 535b formed in the inner metal member 530a is folded back toward the inner side, that is, the partially convex spherical surface 121 side. The inner edge portion of the through hole 535a formed in the outer metal member 530a is folded back to the outer side, that is, the partially concave spherical surface 111 side. The rigid sphere 150 is held in the rigid sphere holding hole 535 in a state of being fitted to the inner edge portions of the through holes 535a and 535b.

  The outer metal member 530 a is provided with a flange portion 534 a that faces the flange portion 114 of the first seat body 110. The inner metal member 530 b is provided with a flange portion 534 b that faces the flange portion 124 of the second seat body 120. Bolt insertion holes 533a and 533b communicating with each other are formed in both flange portions 534a and 534b, and stepped bolts 141 are inserted into the bolt insertion holes 533a and 533b so as to be relatively swingable and slidable.

  In addition, the annular member 530 is forcibly set by the holding member 170 (elastic body) to hold the relative positional relationship between the ring member 530 and the second seat 120 (that is, the upstream exhaust pipe 201). It is pressed against the body 120. Providing the holding member 170 facilitates positioning of the annular member 530 in the production stage of the pipe joint 500 and prevents excessive movement of the annular member 530 in the axial direction when the pipe joint 500 is used. Can be prevented. The holding member 170 is made by bending a stainless steel rod-like member, and has sufficient rigidity and elasticity to suppress an excessive movement of the ring member 530 and return it to a fixed position. The both ends of the holding member 170 of this example pass through the holding member through hole 128 of the flange portion 124 and are welded and fixed in the vicinity of the tightening position of the nut 144, and the intermediate portion thereof connects the flange portion 534 a of the ring member 530. It is pressing (see FIG. 8).

  The pipe joint 500 configured as described above is configured such that the bending margin 531a portion of the outer metal member 530a constituting the annular member 530 is brought into contact with the partial concave spherical surface 111 of the first seat 110 over the entire circumference. The portion of the bending margin 531b of the metal member 530b is brought into contact with the partially convex spherical surface 121 over the entire circumference, and the space between the both seats 110 and 120 is sealed. The portion of the bending allowance 531a of the outer metal member 530a is locally in contact with the partially concave spherical surface 111 (linear or belt-like). The portion of the bending allowance 531b of the inner metal member 530b is in local contact with the partially convex spherical surface 121 (in a linear or belt shape). The rigid sphere 150 and the seal portion 530A are slidable relative to the partially concave spherical surface 111 and the partially convex spherical surface 121, thereby allowing relative swinging of both the tubes 201 and 202.

  Also in this pipe joint 500, four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat body 110 and the partially convex spherical surface 121 of the second seat body 120, and the both seat bodies 110, 120. Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. Since the pressure (contact pressure) acting between 120 and the ring member 530 is always kept constant, the sealing performance between the seats 110 and 120 by the ring member 530 is always kept stable.

  Therefore, according to this pipe joint 500, even if a slight vibration occurs in one of the upstream side exhaust pipe 201 and the downstream side exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed. The annular member 530 is manufactured because the outer metal member 530a and the inner metal member 530b are bent, and the two members 530a and 530b are overlapped to be hermetically joined, leaving portions of the bending margins 531a and 531b. Easy.

[Sixth embodiment]
FIG. 6 is a partial front view of an annular member of a pipe joint according to the present invention. 7 is a cross-sectional view of the pipe joint of FIG. 6 (a cross-sectional view taken along line A of FIG. 6). 8 is another cross-sectional view of the pipe joint of FIG. 6 (a cross-sectional view taken along line B of FIG. 6). In these drawings, members that are the same as those in the pipe joint of FIG. 1 or FIG.

  In this pipe joint 600, since the structure other than the ring member 630 is the same as that of the pipe joint 500, the description thereof is omitted.

The annular member 630 includes an annular outer metal member 630a facing the partially concave spherical surface 111 of the first seat 110 and an annular inner metal member 630b (630b ₁ , 630b) facing the partially convex spherical surface 121 of the second seat 120. ₂ ) and overlapping with each other in an airtight manner while leaving bending allowances 631a and 631b at the small diameter side ends.

The first inner metal member 630b ₁ is joined to the small diameter side opening end of the outer metal member 630a. The second inner metal member 630b ₂ is joined to the large-diameter opening end of the outer metal member 630a.

  The ring member 630 is in contact with the partially concave spherical surface 111 and the partially convex spherical surface 121 locally (linearly or belt-like), and extends between the first seat 110 and the second seat 120 over the entire circumference. An annular seal portion 630A formed so as to be sealed, and a rigid sphere holding portion 630B that holds the plurality of rigid spheres 150 collectively while keeping the positional relationship between the rigid spheres in the circumferential direction constant.

  The seal portion 630A has a resilience and restoration property by bending a portion of the bending allowance 631a of the outer metal member 630a to make contact with the partial concave spherical surface 111 over the entire circumference, and the bending allowance 631b of the outer metal member 630b. The part is bent so as to have a resilience and restoration property, and is brought into contact with the partial convex spherical surface 121 over the entire circumference.

  The bending margin 631a of the outer metal member 630a is formed with an annular contact portion 632a that contacts the partially concave spherical surface 111 so as to border the inner edge portion thereof. The bending margin 631b of the inner metal member 630b is formed with an annular contact portion 632b that contacts the partially convex spherical surface 121 so as to border the inner edge portion thereof. The cross-sectional shapes of the contact portions 632a and 632b are substantially arc shapes. Further, a lubricant layer is formed on the contact portions 632a and 632b.

  The rigid sphere holding portion 630 </ b> B includes four rigid sphere holding holes 635 provided at equal intervals in the circumferential direction of the ring member 630. The rigid sphere holding hole 635 is formed by penetrating the outer metal member 630a and the inner metal member 630b to each other to form through holes 635a and 635b. The inner edge portion of the through hole 635b formed in the inner metal member 630b is folded back to the inner side, that is, the partially convex spherical surface 121 side. The inner edge portion of the through hole 635a formed in the outer metal member 630a is folded back to the outer side, that is, the partially concave spherical surface 111 side. The rigid sphere 150 is held in the rigid sphere holding hole 635 in a state of being fitted to the inner edge portions of the through holes 635a and 635b.

  The outer metal member 630 a is provided with a flange portion 634 a that faces the flange portion 114 of the first seat body 110. The inner metal member 630 b is provided with a flange portion 634 b that faces the flange portion 124 of the second seat body 120. Both flange portions 634a and 634b are formed with bolt insertion holes 633a and 633b communicating with each other, and the stepped bolt 141 is inserted into the bolt insertion holes 633a and 633b so as to be capable of relative swinging and sliding.

The above configuration is the same as that of the fifth embodiment. Of the outer metal member 630a and the inner metal member 630b constituting the ring member 630 of this embodiment, the inner metal member 630b has an outer metal member 630a that borders the bending allowance 631b and the bending allowance 631b. It consists of a first metal member 630b ₁ consisting only of a joint part that is airtightly joined, and a second metal member 630b ₂ that constitutes a rigid sphere holding part 630B together with the outer metal member 630a. The outer metal member 630a is formed with a notch hole 630D leaving a bridge portion 630C that connects the seal portion 630A and the rigid sphere holding portion 630B.

In the pipe joint 600 configured as described above, the bending margin 631a of the outer metal member 630a constituting the annular member 630 is brought into contact with the partial concave spherical surface 111 of the first seat body 110 over the entire circumference. The portion of the bending margin 631b of the one metal member 630b ₁ is brought into contact with the partial convex spherical surface 121 over the entire circumference, thereby sealing between the both seats 110, 120. The portion of the bending allowance 631a of the outer metal member 630a is in local contact (linearly or strip-shaped) with the partially concave spherical surface 111. The portion of the bending allowance 631b of the first metal member 630b ₁ is in local contact with the partially convex spherical surface 121 (linearly or strip-shaped). The rigid sphere 150 and the seal portion 630A are slidable relative to the partially concave spherical surface 111 and the partially convex spherical surface 121, thereby permitting relative swinging of both the tubes 201 and 202.

  Also in this pipe joint 600, four rigid spheres 150 are sandwiched between the partially concave spherical surface 111 of the first seat 110 and the partially convex spherical surface 121 of the second seat 120, and the Since the positions of the rigid spheres 150 in the circumferential direction are kept constant, the distance between the partially concave spherical surface 111 and the partially convex spherical surface 121 is always kept constant. Since the pressure (contact pressure) acting between 120 and the ring member 530 is always kept constant, the sealing performance between the seats 110 and 120 by the ring member 630 is always kept stable.

  Therefore, according to this pipe joint 600, even if a slight vibration occurs in one of the upstream side exhaust pipe 201 and the downstream side exhaust pipe 202, the minute vibration is prevented from being transmitted to the other pipe as much as possible. At the same time, the generation of abnormal sounds (stagnation sounds) can be suppressed.

In addition, this pipe joint 600 is composed of only a joint portion in which the inner metal member 630b constituting the annular member 630 is airtightly joined to the outer metal member 630a so as to border the bending margin 631b and the bending margin 631b. 1 metal member 630b ₁ and a second metal member 630b ₂ that constitutes a rigid sphere holding portion 630B together with the outer metal member 630a. By forming the notch hole 630D while leaving the bridge portion 630C, compared with the pipe joint of Configuration 5, the weight of the annular member is reduced, and at the connection portion between the rigid ball holding portion and the seal portion, that is, the bridge portion The sealing property between the two seats by the seal portion can be enhanced by providing flexibility.

  The rigid sphere 150 used in the pipe joint of the present invention is not particularly limited, but preferably a stainless steel ball, a ceramic ball or the like is used, and a silicon nitride ceramic ball is more preferably used. Silicon nitride ceramic balls are hard and lightweight, and are excellent in durability, and can easily absorb minute vibrations due to smoothness. In addition, since the materials of the ball and the flange are different, the generation of micropits (fine irregularities) can be prevented, and the performance can be maintained for a long time.

  Moreover, as a material of the sealing body used as the ring member described in each of the above embodiments, for example, a heat-resistant sealing material composed of an inorganic filler or a carbonized material, a stainless wire mesh compressed product, or a stainless wire mesh compressed product And a mixture of heat resistant resin and the like. And it is preferable that the lubricant layer is formed in the surface of the sealing body which consists of one of these heat resistant materials. Further, a layer having heat resistance and lubricity may be formed on the partially concave spherical surface 111 and the partially convex spherical surface 121.

  In the pipe joint of the present invention, the rigid sphere 150 may be rotatably held by the annular member.

  The number of the rigid spheres 150 provided in the pipe joint of the present invention is at least three. Therefore, in the above example, the case where the number of the hard spheres 150 is four has been described, but may be three or five or more.

Sectional drawing of the principal part showing the first embodiment of the pipe joint according to the present invention Sectional drawing of the principal part showing a second embodiment of the pipe joint according to the present invention Sectional drawing of the principal part showing a third embodiment of the pipe joint according to the present invention (A) is principal part sectional drawing which shows the pipe joint concerning this invention, (b) is a whole perspective view of the annular member with which the pipe joint shown to (a) is equipped. Sectional drawing of the principal part showing a fifth embodiment of the pipe joint according to the present invention Cross-sectional view of relevant parts showing a sixth embodiment of the pipe joint according to the present invention Sectional view of the pipe joint shown in FIG. Another sectional view of the pipe joint shown in FIG.

Explanation of symbols

100, 200, 300, 400, 500, 600 Pipe joint 110 First seat body 111 Partial concave spherical surface 113 Bolt fixing hole 114, 124 Flange portion 116 Holding member engagement hole 117, 127 Cover portion 120 Second seat body 121 Partial convexity Spherical surface 123 Bolt insertion hole 128 Holding member through hole 130, 230, 330, 430, 530, 630 Ring member 135, 235, 339, 438, 535, 635 Through hole 140 Energizing mechanism 141 Bullet bolt 143 Coil spring 144 Nut 150 Hard sphere 170 Holding member 201 Upstream exhaust pipe 202 Downstream exhaust pipe

Claims (7)

In a pipe joint that connects one pipe and the other pipe so that they can swing relative to each other,
An annular first seat body having a partially concave spherical surface that is fixed to the outer peripheral surface of the one pipe and expands to the other pipe side;
Fixed to the outer peripheral surface of the other pipe,
An annular second seat having a partially convex spherical surface that is reduced in diameter toward the one tube side and is provided to face the partially concave spherical surface;
A plurality of hard spheres of the same diameter sandwiched between the partially concave spherical surface and the partially convex spherical surface;
Sealing between the first seat and the second seat over the entire circumference while locally contacting the partially concave spherical surface and the partially convex spherical surface, and the plurality of rigid spheres as the rigid bodies An annular member that holds the balls together while maintaining the positional relationship in the circumferential direction constant,
An urging mechanism for urging the first seat and the second seat so as to approach each other in the tube axis direction. The ring member is a spherically shaped seal body having a partially concave spherical inner peripheral surface facing the convex spherical surface and a partially convex spherical outer peripheral surface facing the partial concave spherical surface,
An annular protrusion that contacts the partial concave spherical surface over the entire circumference;
An annular protrusion contacting the partial convex spherical surface over the entire circumference;
A through hole formed by penetrating the seal body in the direction between the inner and outer peripheral surfaces to hold the rigid sphere in a accommodated state,
The pipe joint according to claim 1, wherein the rigid sphere partially protrudes from the inner and outer peripheral surfaces of the seal body in a state of being accommodated in the through hole. The ring member is
A rigid sphere holding portion that collectively holds the plurality of hard spheres;
A first seal portion located on a smaller diameter side of the annular member than a formation position of the rigid sphere holding portion;
The pipe joint according to claim 1, further comprising: a second seal portion located on a larger diameter side of the annular member than a position where the rigid sphere holding portion is formed. The ring member is
4. The pipe joint according to claim 3, wherein the pipe joint is a metal integral-molded product having a substantially truncated cone shape or a substantially spherical band shape which is molded so as to have resilience and resilience against deformation caused by an external force. The annular member overlaps the annular outer metal member facing the partially concave spherical surface and the annular inner metal member facing the partially convex spherical surface, and is airtightly joined to each other leaving a bending margin at the small diameter side end. And
An annular seal portion formed so as to seal between the first seat body and the second seat body over the entire circumference while locally contacting the partially concave spherical surface and the partially convex spherical surface; A rigid sphere holding part that holds the plurality of rigid spheres together while maintaining a positional relationship in the circumferential direction between the rigid spheres; and
The sealing portion has a rebound restoring property by bending the bending margin portion of the outer metal member to contact the partial concave spherical surface over the entire circumference and the bending margin portion of the inner member. The pipe joint according to claim 1, wherein the pipe joint is configured to be brought into contact with the partial convex spherical surface over the entire circumference by giving a rebound restoring property by bending. Either one of the outer metal member and the inner metal member includes a first metal member including only a bending portion and a joint portion airtightly bonded to the other member so as to border the bending margin. A second metal member constituting the rigid sphere holding portion together with the other member,
6. The pipe joint according to claim 5, wherein the other member is formed with a notch hole leaving a bridge portion connecting the seal portion and the rigid sphere holding portion.   The pipe joint according to any one of claims 4 to 6, wherein a lubricant layer is formed at a contact portion between the partial concave spherical surface and the partial convex spherical surface of the annular member.