JP2008069903A - Tripod type constant velocity joint and its roller unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tripod type constant velocity joint whose roller can be unitized. <P>SOLUTION: A roller unit 30 comprises a roller body 311 forming a first ring groove 311a, a collar portion 312 formed integrally with the roller body 311, an upper side washer member 32 formed separately from the roller body 311 and arranged on the lower opening side of the collar portion 312, a lower side snap ring 33 fitted into the first ring groove 311a, a lower side washer member 34 arranged on the upper opening side of the lower side snap ring 33, and a plurality of needles 35. The upper side washer member 32 has an upper member protruded ring portion 32a protruded on the lower opening side over the peripheral direction of the end face inner periphery, and the lower side washer member 34 has a lower member protruded ring portion 34a protruded on the upper opening side over the peripheral direction of the end face inner periphery. The plurality of needles 35 are laid between the upper side washer member 32 and the lower side washer member 34 for engaging the upper member protruded ring portion 32a and the lower member protruded ring portion 34a in the radial direction of the roller. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tripod type constant velocity joint used in, for example, a front wheel drive type automobile and the like and a roller unit constituting the same.

  The tripod type constant velocity joint includes those described in the prior art of Patent Document 1 and FIG. The roller of this tripod type constant velocity joint is composed of a plurality of needle-shaped cylindrical needles between the washers attached to the base end side and the tip end side of the outer peripheral surface of the tripod shaft portion. It consists of a structure arranged over the circumference. That is, both washers prevent the plurality of needles from falling off. However, with such a roller configuration, it is difficult to assemble the needle over the entire outer peripheral surface of the tripod shaft, and many man-hours are required.

  Therefore, in order to improve the assembly workability, tripod type constant velocity joints disclosed in Patent Literature 1 and Patent Literature 2 have been proposed. This tripod type constant velocity joint improves assembly workability by unitizing rollers. Specifically, this roller unit forms a collar portion that prevents a plurality of needles from dropping off at both ends of the inner peripheral surface of the roller body, and the needles are geometrically dropped along the collar portion. It is to prevent.

Also, Patent Document 3 and Patent Document 4 disclose a tripod type constant velocity joint in which rollers are unitized. In this roller unit, a plurality of needles are held by a shell-shaped outer ring having a substantially U-shaped cross section having flanges at both ends. And this shell type outer ring | wheel is arrange | positioned at the inner peripheral side of the roller main-body part.
Japanese Patent Laid-Open No. 10-184717 JP 2003-28186 A Japanese Utility Model Publication No. 56-158524 JP 2001-65590 A

  However, in the roller units of Patent Documents 1 and 2, it is necessary to provide a certain clearance between adjacent needles. Therefore, in order to prevent the needle after press-fitting from falling off, the diameter of the needle is increased to some extent. There must be. Therefore, the outer diameter of the entire roller unit is increased, resulting in a problem that the tripod constant velocity joint is increased in size. Furthermore, the number of needles is relatively reduced by increasing the diameter of the needle. Therefore, there arises a problem that the surface pressure received by each needle and tripod shaft portion becomes relatively large.

  Further, in the roller units of Patent Documents 3 and 4, when the needle is inserted into the shell-shaped outer ring, the flange portion of the shell-shaped outer ring is deformed outward. If the plastic deformation occurs, the opening distance of the shell-shaped outer ring is increased, so that the amount of needle catching is reduced, and the needle may fall off.

  Furthermore, a shell-shaped outer ring exists between the roller body and the needle in the radial direction of the roller. Therefore, there are three parts that contact in the torque transmission direction between the tripod shaft and the outer race: the needle, the shell-shaped outer ring, and the roller body. Here, the larger the number of parts, the more loose the entire roller due to the backlash between parts. The larger the play, the lower the accuracy of the tripod type constant velocity joint. That is, it is desired to reduce the number of parts that make contact in the torque transmission direction. Specifically, in order to reduce the number of parts, a configuration in which the needle and the roller main body portion are in direct contact is desired.

  Furthermore, both end sides of the shell-shaped outer ring are pressed from both end sides with the needle sandwiched therebetween. Therefore, a large sliding friction is generated between the needle and the shell-shaped outer ring, which may affect the rolling of the needle. Further, this sliding friction increases energy loss.

  An object of this invention is to provide the roller unit which can solve such a problem, and the tripod type | mold constant velocity joint using the roller unit.

  The tripod type constant velocity joint of the present invention includes an outer race, a tripod, and a roller unit. The outer race has a cup shape, and three guide grooves extending in the outer race rotation axis direction are formed on the inner peripheral surface. The tripod is connected to a shaft (for example, an intermediate shaft of the drive shaft), and extends from the boss portion to the outside in the radial direction of the shaft axis (shaft center) and is inserted into each guide groove. And three tripod shafts. The roller unit has a ring shape, is pivotally supported by each tripod shaft portion so as to be rotatable around the tripod shaft, and engages with the guide groove so as to be able to roll.

  The roller unit is configured in detail as follows. That is, the roller unit includes a roller main body, a first member, a second member, and a plurality of needles. The roller unit is formed in a ring shape, and its outer peripheral surface engages with each guide groove so as to be able to roll, and forms a first ring groove over the entire circumference on one opening side of at least the inner peripheral surface.

  The first member is formed in a ring shape that is formed integrally with or separately from the roller main body, and has a first projecting ring portion that protrudes in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface. It arrange | positions at the other opening side among the internal peripheral surfaces of a roller main-body part so that a protruding ring part may face one opening side of a roller main-body part. The second member is formed in a ring shape formed separately from the roller main body and the first member, and has a second protruding ring portion protruding in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface, The second projecting ring portion is fitted into the first ring groove so as to face the other opening side of the roller body portion.

  The needle has a needle-like columnar shape, and is disposed on the inner peripheral side of the roller main body so as to be able to roll on the inner peripheral surface of the roller main body, and is disposed on the outer peripheral surface of the tripod shaft so as to be capable of rolling. It arrange | positions so that it may interpose between a member and a 2nd member, and it engages with a roller rotating shaft radial direction with respect to a 1st protrusion ring part and a 2nd protrusion ring part.

  According to the roller unit of the tripod type constant velocity joint having such a configuration, the needle is dropped inside the roller main body by the first protruding ring portion of the first member and the second protruding ring portion of the second member. Can be prevented. That is, the roller can be unitized. Thereby, the already assembled roller unit can be inserted into each tripod shaft portion, and thereafter, an integral part of the tripod and the roller unit can be inserted into the outer race. Thus, the assembly workability of the roller is very good.

  Further, according to the tripod type constant velocity joint roller unit of the present invention, there is no restriction on the size of the needle as in Patent Documents 1 and 2. Therefore, the diameter of the needle can be reduced. That is, the outer diameter of the entire roller unit can be reduced, and as a result, the tripod constant velocity joint can be reduced in size. Since the diameter of the needle can be reduced, the number of needles can be increased. As a result, the surface pressure received by each needle and tripod shaft can be reduced.

  Here, the assembly of the roller unit having the above-described configuration will be briefly described. First, before the second member is fitted into the first ring groove, the needle is disposed on the inner peripheral side of the roller body. At this time, the needle is disposed so as to contact the first member. Thereafter, the second member is fitted into the first ring groove so that the second protrusion of the second member engages with the needle.

  Thus, according to the roller unit of the tripod type constant velocity joint of the present invention, the needle is disposed on the inner peripheral side of the roller main body portion before the second member is fitted into the first ring groove. That is, when assembling the needle, as in Patent Documents 3 and 4, the needle can be assembled without deforming other components. In the case of the roller units described in Patent Documents 3 and 4, as described above, there is a possibility that the opening distance of the shell-shaped outer ring may be increased, so that the needle falls off due to a decrease in the amount of needle catching. There was a fear. However, according to the present invention, since none of the constituent parts is deformed, the amount of hook between the needle and the first ring portion and the amount of hook between the needle and the second ring portion are not reduced. . Therefore, it is possible to reliably prevent the needle from falling off.

  Furthermore, according to the present invention, the needle directly contacts the inner peripheral surface of the roller body and rolls on the inner peripheral surface. That is, there are only two parts that contact the torque transmission direction between the tripod shaft and the outer race: the needle and the roller main body. Accordingly, the number of parts is reduced as compared with the roller units described in Patent Documents 3 and 4. That is, the play of the entire roller can be reduced, and as a result, the accuracy of the tripod constant velocity joint is improved.

  Furthermore, although the needle is interposed between the first member and the second member, the needle is not pressed by the first member and the second member. The 1st member and the 2nd member should just be located in the position where a needle engages with the 1st protruding ring part and the 2nd protruding ring part. That is, according to the present invention, unlike the roller units described in Patent Documents 3 and 4, large sliding friction due to the shell-shaped outer ring pressing the needle does not occur. As a result, energy loss due to sliding friction can be reduced without adversely affecting the rolling of the needle.

  The first projecting ring part and the second projecting ring part both project in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end face, but only when they are formed over the entire circumference. The case where it is formed over substantially the entire circumference is also included. For example, when the first member or the second member has a ring shape in which a slit such as a snap ring described later is formed, the first projecting ring portion or the second projecting ring portion is formed in the portion where the slit is formed. Is not formed, but it is meant to include such a case.

  Here, the 1st member and the 2nd member which comprise the roller unit of the tripod type | mold constant velocity joint of this invention can also be made as follows.

  The first member may be formed integrally with the roller body. In this case, the number of parts is reduced, and the cost can be reduced by reducing the number of assembly steps.

  Moreover, you may make it another 1st member be provided with a collar part and a 1st latching member. The flange portion has a ring shape and is integrally formed on the other opening side of the inner peripheral surface of the roller main body portion so as to protrude inward from the inner peripheral surface. The first locking member has a ring shape formed separately from the collar portion, and has a first protruding ring portion that protrudes in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface. The ring portion is disposed so as to face the one opening side of the roller body portion, is disposed on the one opening side of the roller body portion from the flange portion, and is disposed so as to engage with the flange portion in the roller rotation axis direction. The

  That is, in the first member, the collar portion is formed integrally with the roller body portion, but the first locking member is formed separately from the roller body portion. When the entire first member as described above is formed integrally with the roller main body, the first protrusion is smaller than the size of the roller main body, so that the processing of the first protrusion is not easy. Absent. Therefore, there is a possibility that the processing cost of an integrated product of the roller body and the first member may increase. On the other hand, although the number of parts increases by making the 1st locking member which has a 1st ring part separate from a roller main-body part, processing cost can be reduced.

  The other first member may be as follows. First, a roller main-body part forms a 2nd ring groove over the perimeter on the other opening side among inner peripheral surfaces. The first member has a ring shape that is formed separately from the roller body, and is fitted into the second ring groove.

  That is, the first member is entirely formed separately from the roller main body, and is attached to the roller main body by being fitted into the second ring groove. In this case as well, the number of parts increases as in the case where the first member includes the flange portion and the first locking member, but the processing cost can be reduced.

  If the first member is configured to be fitted into the second ring groove, and the entire first member is composed of one part, the first member is fitted into the second ring groove. It becomes a ring shape in which a slit like a so-called snap ring is formed. And the part in which the slit is formed cannot form a 1st protruding ring part over the perimeter. Depending on the size of the slit, when the needle rolls on the inner peripheral surface of the roller body, the needle may be caught by the slit, and the needle may not roll appropriately.

  Therefore, the other first member when fitted in the second ring groove is preferably as follows. That is, the first member includes a first snap ring and a second locking member. The first snap ring has a ring shape, is fitted in the second ring groove, and protrudes inward from the inner peripheral surface of the roller main body. The second locking member has a ring shape formed separately from the first snap ring, and has a first protruding ring portion protruding in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface. One protruding ring portion is disposed so as to face the one opening side of the roller body portion, is disposed on the one opening side of the roller body portion from the first snap ring, and is engaged with the first snap ring in the roller rotation axis direction. Arranged to match.

  As described above, since the first member includes the first snap ring and the second locking member, no slit is formed in the second locking member in contact with the needle. Furthermore, the 1st protruding ring part of the 2nd latching member is formed over the perimeter. Therefore, adverse effects due to the formation of the slit can be prevented.

  Moreover, you may make it the whole 2nd member consist of one component. In this case, the number of parts is reduced, and the cost can be reduced by reducing the number of assembly steps.

  However, when the second member as a whole is made up of a single component, the second member has a ring shape in which a slit like a so-called snap ring is formed in order to fit into the first ring groove. And the part in which the slit is formed cannot form the 2nd protruding ring part over the perimeter. Depending on the size of the slit, when the needle rolls on the inner peripheral surface of the roller body, the needle may be caught by the slit, and the needle may not roll appropriately.

  Therefore, the second member may be configured as follows. That is, the second member includes a second snap ring and a third locking member. The second snap ring has a ring shape, is fitted into the first ring groove, and projects inward from the inner peripheral surface of the roller main body. The third locking member is formed in a ring shape formed separately from the second snap ring, and has a second protruding ring portion protruding in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface. 2 The projecting ring portion is disposed so as to face the other opening side of the roller body portion, is disposed on the other opening side of the roller body portion from the second snap ring, and is engaged with the second snap ring in the roller rotation axis direction. Arranged to match.

  As described above, since the second member includes the second snap ring and the third locking member, no slit is formed in the third locking member in contact with the needle. Furthermore, the 2nd protruding ring part of the 3rd latching member is formed over the perimeter. Therefore, adverse effects due to the formation of the slit can be prevented.

  Here, in the above description, the present invention has been described as a tripod type constant velocity joint. However, the present invention can be similarly understood as a roller unit of a tripod type constant velocity joint.

  That is, the tripod type constant velocity joint roller unit of the present invention is a tripod type constant velocity joint roller unit rotatably supported around the tripod shaft on the tripod shaft portion, and includes a roller body portion and a first member. And a second member and a plurality of needles. Here, the roller main body, the first member, the second member, and the needle are the same as the members of the roller unit constituting the tripod type constant velocity joint.

  According to the tripod type constant velocity joint and the roller unit thereof according to the present invention, since the roller can be unitized, the assembling workability is improved. At this time, it is possible to reliably prevent the needle from falling off. Further, the tripod constant velocity joint can be reduced in size, and the surface pressure received by the needle and tripod shaft can be reduced. Furthermore, the accuracy of the tripod type constant velocity joint can be improved. Furthermore, the rolling of the needle can be improved and energy loss can be reduced.

  Next, the present invention will be described in more detail with reference to embodiments. Here, the tripod type constant velocity joint of the present embodiment will be described by taking as an example a case where it is used for connection of a power transmission shaft (particularly, a drive shaft) of a vehicle. Specifically, this is a case where the shaft portion connected to the differential gear and the intermediate shaft are used as a connecting portion.

(1) 1st Embodiment The tripod type | mold constant velocity joint of 1st Embodiment is demonstrated with reference to FIG. FIG. 1 is a partial cross-sectional view of a tripod constant velocity joint in the axial direction of the intermediate shaft.

  The tripod type constant velocity joint includes an outer race 10 connected to a differential gear (not shown), a tripod 20 connected to an intermediate shaft (not shown), and a roller interposed between the outer race 10 and the tripod 20. The unit 30 is configured.

  The outer race 10 is formed in a cup shape (bottomed cylindrical shape), and the outer side of the cup bottom is connected to a differential gear. Three guide grooves 11 extending in the outer race rotation axis direction (front-rear direction in FIG. 1) are formed at equal intervals on the inner peripheral surface of the cup-shaped portion of the outer race 10. In FIG. 1, only one guide groove 11 is shown.

  The tripod 20 is disposed inside the cup-shaped portion of the outer race 10. The tripod 20 includes a boss portion 21 and three tripod shaft portions 22. The boss portion 21 has a cylindrical shape, and an inner peripheral spline is formed on the inner peripheral side. This inner peripheral spline is connected to the outer peripheral spline at the end of the intermediate shaft. Each tripod shaft portion 22 extends outwardly in the radial direction of the intermediate shaft shaft (axial center of the tripod 20) on the outer peripheral side of the boss portion 21 and is equally spaced in the circumferential direction of the boss portion 21. Is formed. The tripod shaft portion 22 has a cylindrical shape. The tip portion of each tripod shaft portion 22 is inserted into each guide groove 11 of the outer race 10.

The roller unit 30 has a ring shape as an overall shape. The roller unit 30 is provided on the outer peripheral side of the tripod shaft portion 22 so as to be rotatable about a tripod shaft (the axis of the tripod shaft portion 22, the vertical direction in FIG. 1) and slidable in the tripod shaft direction. It is supported. Furthermore, the roller unit 30 is engaged with the guide groove 11 so that it can roll. More specifically, the roller unit 30 includes a roller member 31, an upper washer member 32, a lower snap ring 33, a lower washer member 34, and a plurality of needles 35.
The roller member 31 has a substantially cylindrical shape as a whole. Specifically, the roller member 31 includes a roller main body portion 311 and a flange portion 312. The roller body 311 has a cylindrical shape. The outer peripheral surface of the roller body 311 has a shape that follows the guide groove 11. Accordingly, the roller main body 311 engages with the guide groove 11 so as to be able to roll around the vertical axis in FIG. 1 (around the tripod axis). The inner peripheral surface side of the cross section of the roller main body 311 has a linear shape parallel to the tripod shaft of the tripod shaft portion 22. Furthermore, a lower ring groove 311a (corresponding to the first ring groove in the present invention) is formed on the inner peripheral surface of the roller main body 311 over the entire circumference on the lower opening side in FIG.

  The flange portion 312 is integrally formed with the roller main body portion 311 at the end portion on the upper opening side in FIG. 1 of the inner peripheral surface of the roller main body portion 311 so as to protrude inward from the inner peripheral surface. The flange portion 312 has a ring shape whose inner diameter is slightly larger than the outer diameter of the tripod shaft portion 22.

  The upper washer member 32 (corresponding to a part of the first member of the present invention and the first locking member) has a ring shape formed separately from the roller main body portion 311 and the flange portion 312. The outer diameter of the upper washer member 32 is slightly smaller than the outer diameter of the flange portion 312, that is, the inner diameter of the roller main body portion 311 and larger than the inner diameter of the flange portion 312. Further, the inner diameter of the upper washer member 32 is slightly smaller than the inner diameter of the flange portion 312. Further, the inner and outer diameters of the upper washer member 32 are set such that the upper washer member 32 does not contact the tripod shaft portion 22 in relation to the needle 35 described later.

  Further, the upper washer member 32 corresponds to the upper member abutment portion 32a (corresponding to the first abutment portion of the present invention) protruding in the roller rotation axis direction (vertical direction in FIG. 1) over the entire circumference on the inner peripheral side of the end face. ). The upper member protruding ring portion 32a is formed so as to become gradually narrower from the root toward the tip when viewed in an axial cross section. Furthermore, the outer peripheral surface side of the upper member protruding ring portion 32a is formed by a curved surface that protrudes outward. That is, the ratio of the width of the upper member projecting ring portion 32a (the width in the left-right direction in FIG. 1) narrowing from the root toward the tip is reduced toward the root and increased toward the tip. The outer peripheral surface side of the upper member protruding ring portion 32a has a shape that follows the shape of an end portion of a needle 35 to be described later.

  The upper washer member 32 is disposed so that the upper member protruding ring portion 32a faces the lower opening side of the roller main body portion 311 and is superimposed on the lower opening side of the roller main body portion 311 from the flange portion 312. Has been. That is, the upper washer member 32 is disposed so as to engage with the flange portion 312 in the roller rotation axis direction.

  The lower snap ring 33 (corresponding to a part of the second member of the present invention and the second snap ring) is formed separately from the roller member 31 and the upper washer member 32, and has a slit (not shown). ) Is formed in a ring shape. The outer diameter of the lower snap ring 33 is smaller than the groove bottom diameter of the lower ring groove 311a. Further, the inner diameter of the lower snap ring 33 is formed to be substantially equal to the inner diameter of the flange portion 312. The lower snap ring 33 is fitted in the lower ring groove 311a of the roller body 311. That is, the lower snap ring 33 protrudes inward from the inner peripheral surface of the roller body 311.

  The lower washer member 34 (corresponding to a part of the second member and the third locking member of the present invention) is formed separately from the roller member 31, the upper washer member 32, and the lower snap ring 33. It consists of a ring. The inner and outer diameters of the lower washer member 34 have the same relationship as the inner and outer diameters of the upper washer member 32. Furthermore, the lower washer member 34 has a lower member projecting ring portion 34a (corresponding to the second projecting ring portion of the present invention) projecting in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end face. The detailed shape of the lower member protrusion 34a is the same as that of the upper member protrusion 32a of the upper washer member 32.

  The lower washer member 34 is overlapped on the upper opening side of the roller main body 311 from the lower snap ring 33 so that the lower member protrusion 34a faces the upper opening side of the roller main body 311. Has been placed. That is, the lower washer member 34 is arranged to engage with the lower snap ring 33 in the roller rotation axis direction.

  The needle 35 is formed of a so-called toggling surface needle roller. That is, the needle 35 has a needle-like substantially cylindrical shape, and both end portions thereof have a shape that gradually becomes narrower toward the tip side. Specifically, the cross-sectional shape of both ends of the needle 35 is formed as a concave curved surface.

  The needle 35 is disposed on the inner peripheral side of the roller main body 311 so as to roll on the inner peripheral surface of the roller main body 311. Further, the needle 35 is disposed so as to be interposed between the upper washer member 32 and the lower washer member 34. At this time, the needle 35 is in the roller rotation shaft radial direction (see FIG. 5) with respect to the outer peripheral side surface of the upper member ring portion 32a of the upper washer member 32 and the outer peripheral side surface of the lower member ring portion 34a of the lower washer member 34. 1 in the left-right direction). That is, the needle 35 is held so as not to drop off on the inner peripheral side of the upper member protruding ring portion 32a and the lower member protruding ring portion 34a. Further, the needle 35 is disposed on the outer peripheral surface of the tripod shaft portion 22 so as to be able to roll.

  Next, a method for assembling the roller unit 30 will be described. First, the roller member 31 is inserted into a shaft-shaped jig (not shown) corresponding to the shape of the tripod shaft portion 22. At this time, the collar portion 312 is positioned on the lower side. That is, they are arranged in the upside down direction in FIG.

  Subsequently, the upper washer member 32 is inserted into the gap between the roller main body portion 311 and the jig so that the upper member protruding ring portion 32a faces upward. Subsequently, the plurality of needles 35 are inserted into the gaps between the roller body 311 and the jig. That is, the plurality of needles 35 are arranged on the upper washer member 32. Subsequently, the lower washer member 34 is inserted into the gap between the roller main body 311 and the jig so that the lower member protruding ring portion 34a faces downward. That is, the lower washer member 34 is disposed on the plurality of needles 35. Finally, the lower snap ring 33 is fitted into the lower ring groove 311a. This step may be performed while the components of the roller unit 30 are arranged on the jig, or may be performed while being removed from the jig.

  As described above, in the roller unit 30, the needle 35 can be reliably prevented from falling off. That is, the roller unit 30 can be unitized. Moreover, since the diameter of the needle 35 can be set freely, the surface pressure which each needle 35 and the tripod shaft part 22 receive can be made as small as possible. Moreover, in the roller unit 30, any component can be assembled without being deformed. Therefore, the needle 35 can be reliably held. Further, since the needle 35 rolls in direct contact with the inner peripheral surface of the roller main body 311, the play of the entire roller in the torque transmission direction can be minimized. That is, the accuracy of the tripod constant velocity joint can be improved. Further, the upper washer member 32 and the lower washer member 34 are not in a state of pressing the needle 35. Therefore, the sliding friction between the needle 35 and the upper washer member 32 or the lower washer member 34 can be minimized. As a result, the rolling of the needle 35 can be made smooth, and energy loss due to sliding friction can be reduced.

  In particular, a needle-shaped roller is used as the needle 35, and the upper member projecting portion 32a of the upper washer member 32 and the lower member projecting portion 34a of the lower washer member 34 have the above-described shapes. The posture can be stabilized. Therefore, it is possible to make it difficult for an edge load or an offset load due to skew or the like to occur. Furthermore, the area of the radial cross section of the upper member protruding ring portion 32a and the lower member protruding ring portion 34a can be increased. Therefore, the strength of the upper member protruding ring portion 32a and the lower member protruding ring portion 34a can be increased, and as a result, the needle 35 can be reliably locked.

(2) Second Embodiment A tripod type constant velocity joint according to the second embodiment will be described. Here, the tripod type constant velocity joint of the second embodiment is different from the tripod type constant velocity joint of the first embodiment only in the roller unit 30. Therefore, only the roller unit 40 of the second embodiment will be described below with reference to FIG. FIG. 2 is a partial sectional view of the roller unit 40 of the tripod type constant velocity joint in the roller rotation axis direction. Specifically, the roller unit 40 shown in FIG. 2 corresponds to only the portion corresponding to the portion A of the roller unit 30 shown in FIG. Here, in FIG. 2, about the same structure as the roller unit 30 of 1st Embodiment among the roller units 40 of 2nd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 2, the roller unit 40 includes a roller member 41, a lower snap ring 33, a lower washer member 34, and a plurality of needles 35. Here, the roller unit 40 is different from the roller unit 30 of the first embodiment in that the upper washer member 32 is deleted and the configuration of the roller member 41 is different. Therefore, only the roller member 41 will be described below.

  The roller member 41 has a substantially cylindrical shape as a whole. Specifically, the roller member 41 includes a roller main body portion 311 and a flange portion 412. The roller body 311 is the same as the roller body 311 of the first embodiment.

  The flange portion 412 (corresponding to the first member of the present invention) is a roller main body so as to protrude inward from the inner peripheral surface to the upper opening side end portion in FIG. 2 of the inner peripheral surface of the roller main body portion 311. The unit 311 is integrally formed. The flange portion 412 has a ring shape whose inner diameter is slightly larger than the outer diameter of the tripod shaft portion 22. Furthermore, the collar portion 412 is an upper member projecting ring portion 412a (corresponding to the first projecting ring portion of the present invention) that projects to the lower opening side (the lower side in FIG. 2) over the entire inner peripheral side of the end surface. ). The upper member protruding ring portion 412a has the same shape as the upper member protruding ring portion 32a of the upper washer member 32 of the first embodiment.

  The needle 35 is disposed so as to be interposed between the collar portion 412 and the lower washer member 34. At this time, the needle 35 is in the roller rotating shaft radial direction (FIG. 2) with respect to the outer peripheral side surface of the upper member projecting ring portion 412a of the collar portion 412 and the outer peripheral side surface of the lower member projecting ring portion 34a of the lower washer member 34. In the left-right direction). That is, the needle 35 is held so as not to drop off on the inner peripheral side of the upper member protruding ring portion 412a and the lower member protruding ring portion 34a.

  In this case, compared to the roller unit 30 of the first embodiment, the number of parts can be reduced, so that the cost can be reduced by reducing the number of assembling steps. However, there is a risk of increasing the cost due to the difficulty in processing the upper protrusion 412a.

(3) Third Embodiment A tripod type constant velocity joint roller unit 50 according to a third embodiment will be described with reference to FIG. FIG. 3 is a partial sectional view of the roller unit 50 of the tripod type constant velocity joint in the roller rotation axis direction. Specifically, the roller unit 50 shown in FIG. 3 corresponds to only the portion corresponding to the portion A in the roller unit 30 shown in FIG. Here, in FIG. 3, about the same structure as the roller unit 30 of 1st Embodiment among the roller units 50 of 3rd Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 3, the roller unit 50 includes a roller member 51, an upper snap ring 52, an upper washer member 32, a lower snap ring 33, a lower washer member 34, and a plurality of needles 35. Is done. Here, the roller unit 50 is different from the roller unit 30 of the first embodiment in that the configuration of the roller member 51 is different and an upper snap ring 52 is added. Accordingly, only the roller member 51 and the upper snap ring 52 will be described below.

  The roller member 51 (corresponding to the roller body of the present invention) has a cylindrical shape. The outer peripheral surface of the roller member 51 has a shape that follows the guide groove 11. The inner peripheral surface side of the cross section of the roller member 51 has a linear shape parallel to the tripod shaft of the tripod shaft portion 22. Further, an upper ring groove 51a (corresponding to the second ring groove of the present invention) is formed on the inner peripheral surface of the roller member 51 over the entire circumference on the upper opening side in FIG. 3, and in FIG. A lower ring groove 311a is formed over the entire circumference on the lower opening side.

  The upper snap ring 52 (corresponding to a part of the first member of the present invention and the first snap ring) is formed separately from the roller member 51 and the upper washer member 32, and is a slit (not shown). It consists of a ring shape formed. The outer diameter of the upper snap ring 52 is smaller than the groove bottom diameter of the upper ring groove 51a. Further, the inner diameter of the upper snap ring 52 is formed slightly larger than the outer diameter of the tripod shaft portion 22. The upper snap ring 52 is fitted in the upper ring groove 51 a of the roller member 51. That is, the upper snap ring 52 projects inward from the inner peripheral surface of the roller member 51.

  The upper washer member 32 (corresponding to a part of the second member of the present invention and the second locking member) is arranged so that the upper member protruding ring portion 32a faces the upper opening side of the roller member 51, and The upper snap ring 52 is disposed so as to overlap the lower opening side of the roller member 51. That is, the upper washer member 32 is arranged to engage with the upper snap ring 52 in the roller rotation axis direction.

(4) 4th Embodiment The roller unit 60 of the tripod type | mold constant velocity joint of 4th Embodiment is demonstrated with reference to FIG. FIG. 4 is a partial cross-sectional view of the roller unit 60 of the tripod type constant velocity joint in the roller rotation axis direction. Specifically, the roller unit 60 shown in FIG. 4 corresponds to only the portion corresponding to the portion A in the roller unit 30 shown in FIG. Here, in FIG. 4, about the same structure as the roller unit 30 of 1st Embodiment among the roller units 60 of 4th Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  As shown in FIG. 4, the roller unit 60 includes a roller member 31, an upper washer member 32, a lower locking snap ring 61, and a plurality of needles 35. Here, the roller unit 60 has a lower locking snap ring 61 instead of the lower snap ring 33 and the lower washer member 34 with respect to the roller unit 30 of the first embodiment. Therefore, only the lower locking snap ring 61 will be described below.

  The lower locking snap ring 61 (corresponding to the second member in the present invention) is formed separately from the roller member 31 and the upper washer member 32, and has a ring shape in which a slit (not shown) is formed. Consists of. The outer diameter of the lower locking snap ring 61 is smaller than the groove bottom diameter of the lower ring groove 311a. Further, the inner diameter of the lower locking snap ring 61 is slightly larger than the outer diameter of the tripod shaft portion 22.

  The lower locking snap ring 61 has a lower member projecting ring portion 61a that protrudes in the roller rotation axis direction over the entire circumference excluding the slit portion on the inner peripheral side of the end surface. The lower member protruding ring portion 61a has the same shape as the lower member protruding ring portion 34a of the lower washer member 34 of the first embodiment. The lower locking snap ring 61 is fitted into the lower ring groove 311a of the roller main body 311 so that the lower member protrusion 61a faces the upper opening side of the roller main body 311.

  In this case, compared with the roller units 30, 40, and 50 of the first to third embodiments, the number of parts corresponding to the lower locking snap ring 61 can be reduced, thereby reducing the cost. Can be achieved. However, the lower washer member 34 in the roller units 30, 40, 50 of the first to third embodiments is not formed with a slit corresponding to the lower locking snap ring 61. Therefore, in the fourth embodiment, there is a possibility that a bad effect may be caused by forming a slit in the lower locking snap ring 61.

(5) Fifth Embodiment A roller unit 70 of a tripod type constant velocity joint according to a fifth embodiment will be described with reference to FIG. FIG. 5 is a partial sectional view of the roller unit 70 of the tripod type constant velocity joint in the roller rotation axis direction. Specifically, the roller unit 70 shown in FIG. 5 corresponds to only the portion corresponding to the portion A of the roller unit 30 shown in FIG. Here, in FIG. 5, among the roller units 70 of the fifth embodiment, the same components as those of the roller units 30, 40, 50, 60 of the first to fourth embodiments are denoted by the same reference numerals and described. Omitted.

  As shown in FIG. 5, the roller unit 70 includes a roller member 51, an upper locking snap ring 71, a lower locking snap ring 61, and a plurality of needles 35. Here, the roller unit 70 has an upper locking snap ring 71 instead of the upper snap ring 52 and the upper washer member 32 with respect to the roller unit 50 of the third embodiment, and the lower snap. Instead of the ring 33 and the lower washer member 34, a lower locking snap ring 61 is provided. Since the lower locking snap ring 61 has been described in the fourth embodiment, a detailed description thereof will be omitted. Therefore, only the upper locking snap ring 71 will be described below.

  The upper locking snap ring 71 (corresponding to the first member in the present invention) is formed in the same manner as the lower locking snap ring 61. The upper locking snap ring 71 is fitted into the upper ring groove 51a of the roller main body 311 so that the upper member protruding ring portion 71a faces the lower opening side of the roller main body 311.

  In this case, as compared with the roller unit 50 of the third embodiment, the number of parts corresponding to the lower locking snap ring 61 can be reduced, so that the cost can be reduced.

  In addition, in the said embodiment, although the needle 35 demonstrated using the toggled surface needle-shaped roller, it is not restricted to this. The needle 35 only needs to have a shape in which both end portions become narrower toward the distal end side. For example, both ends of the needle 35 may have various shapes such as a round shape, a spherical shape, a conical shape, and a stepped shape. However, by using the above-described needle surface roller, it is possible to make it less likely to cause an edge load or an offset load due to a skew or the like.

The fragmentary sectional view of the intermediate shaft axial direction of the tripod type constant velocity joint in the first embodiment is shown. The fragmentary sectional view of the roller rotation axis direction of the roller unit 40 of the tripod type constant velocity joint in 2nd Embodiment is shown. The fragmentary sectional view of the roller rotation axis direction of the roller unit 50 of the tripod type constant velocity joint in the third embodiment is shown. The fragmentary sectional view of the roller rotation axis direction of the roller unit 60 of the tripod type constant velocity joint in the fourth embodiment is shown. The fragmentary sectional view of the roller rotation axis direction of the roller unit 70 of the tripod type constant velocity joint in the fifth embodiment is shown.

Explanation of symbols

10: outer race, 11: guide groove,
20: Tripod, 21: Boss part, 22: Tripod shaft part,
30, 40, 50, 60, 70: roller unit 31, 41, 51: roller member,
32: Upper washer member, 32a, 412a, 71a: Upper member protruding ring part,
33: Lower snap ring, 34: Lower washer member,
34a, 61a: lower member protrusion, 35: needle,
51a: upper ring groove 52: upper snap ring,
61: snap ring for lower locking, 71: snap ring for upper locking,
311: Roller body part, 311 a: lower ring groove, 312, 412: collar part

Claims (6)

An outer race having a cup shape and having three guide grooves formed in the inner race surface extending in the direction of the outer race rotation axis;
A tripod comprising: a boss portion connected to the shaft; and three tripod shaft portions that extend from the boss portion in the radial direction of the shaft axis and are inserted into the guide grooves.
A roller unit that is formed in a ring shape, is rotatably supported around the tripod shaft on each of the tripod shafts, and is rotatably engaged with the guide groove;
A tripod type constant velocity joint comprising:
The roller unit is
A roller body that is formed in a ring shape, and whose outer peripheral surface engages with each guide groove in a rollable manner, and forms a first ring groove over the entire circumference on at least one of the inner peripheral surfaces;
The first protruding ring portion has a first protruding ring portion that is formed in a ring shape that is formed integrally with or separately from the roller main body portion, and protrudes in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface. A first member disposed on the other opening side of the inner peripheral surface of the roller main body so that the one faces the one opening side of the roller main body,
It has a ring shape formed separately from the roller main body and the first member, and has a second projecting ring portion projecting in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface, A second member that is fitted into the first ring groove such that a ring-shaped portion faces the other opening side of the roller body portion;
It is formed in a needle-like columnar shape, is disposed on the inner peripheral side of the roller main body so as to be able to roll on the inner peripheral surface of the roller main body, is disposed so as to be able to roll on the outer peripheral surface of the tripod shaft, A plurality of needles arranged so as to be interposed between one member and the second member and engaged with the first projecting ring part and the second projecting ring part in a roller rotation shaft radial direction;
A tripod-type constant velocity joint. The first member is
A collar portion that is formed in a ring shape and is integrally formed so as to protrude inward from the inner peripheral surface to the other opening side of the inner peripheral surface of the roller main body portion;
It has a ring shape formed separately from the flange portion, and has the first protruding ring portion protruding in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface, and the first protruding ring portion is It is arranged to face the one opening side of the roller main body part, is arranged on the one opening side of the roller main body part from the collar part, and engages with the collar part in the roller rotation axis direction. A first locking member disposed on
A tripod constant velocity joint according to claim 1. The roller body portion forms a second ring groove over the entire circumference on the other opening side of the inner peripheral surface,
2. The tripod constant velocity joint according to claim 1, wherein the first member is formed in a ring shape that is formed separately from the roller main body, and is fitted into the second ring groove. The first member is
A first snap ring that is formed in a ring shape, is fitted in the second ring groove, and protrudes inward from the inner peripheral surface of the roller main body;
The first snap ring portion has a ring shape formed separately from the first snap ring, and has the first projecting ring portion protruding in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface. Is disposed so as to face the one opening side of the roller body portion, is disposed closer to the one opening side of the roller body portion than the first snap ring, and the roller rotation shaft with respect to the first snap ring A second locking member arranged to engage in a direction;
A tripod constant velocity joint according to claim 3. The second member is
A second snap ring that is formed in a ring shape, is fitted into the first ring groove, and projects inward from the inner peripheral surface of the roller main body;
The second snap ring portion is formed in a ring shape formed separately from the second snap ring, and has the second projecting ring portion projecting in the roller rotation axis direction over the entire circumference on the inner peripheral side of the end surface. Is disposed so as to face the other opening side of the roller body portion, is disposed on the other opening side of the roller body portion from the second snap ring, and the roller rotation shaft with respect to the second snap ring A third locking member arranged to engage in a direction;
A tripod constant velocity joint according to claim 1. A tripod type constant velocity joint roller unit rotatably supported around the tripod shaft on the tripod shaft,
A roller main body portion that is formed in a ring shape, and whose outer peripheral surface is slidably engaged with the guide groove of each outer race, and that forms a first ring groove over the entire circumference on one opening side of at least the inner peripheral surface;
The first protruding ring portion is formed in a ring shape that is formed integrally or separately with the roller main body portion, and has a first protruding ring portion that protrudes in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface. A first member disposed on the other opening side of the inner peripheral surface of the roller main body so that the one faces the one opening side of the roller main body,
It has a ring shape formed separately from the roller main body and the first member, and has a second projecting ring portion projecting in the roller rotation axis direction over the circumferential direction on the inner peripheral side of the end surface, A second member that is fitted into the first ring groove such that a ring-shaped portion faces the other opening side of the roller body portion;
It is formed in a needle-like columnar shape, and is arranged on the inner peripheral side of the roller main body so as to be able to roll on the inner peripheral surface of the roller main body, and is arranged so as to be able to roll on the outer peripheral surface of the tripod shaft. A plurality of needles arranged so as to be interposed between one member and the second member and engaged with the first projecting ring part and the second projecting ring part in a radial direction of a roller rotation shaft;
A tripod type constant velocity roller unit.

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