JP2004162791A - Tripod constant velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tripod constant velocity universal joint, allowing spherical fitting while keeping a small gap between an inside roller and a spherical journal spherically fitting each other without applying removing work for a forging parting line of the spherical journal. <P>SOLUTION: A relief 16e is partially provided along the forging parting line 16d of the trunnion journal 16b, whereby a boss portion of the forging parting line 16d is set back to the inside further from the spherical outer peripheral face of the trunnion journal 16b. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tripod-type constant velocity universal joint that is incorporated into, for example, a drive system of an automobile and is used for transmitting a rotational force between rotational axes existing on a non-linear line.
[0002]
[Prior art]
A tripod type constant velocity universal joint is widely used as a kind of constant velocity universal joint incorporated in a drive system of an automobile. For example, JP-A-62-233522 discloses a tripod-type constant velocity universal joint 1 as shown in FIGS. The tripod type constant velocity universal joint 1 includes a hollow cylindrical housing 3 fixed to an end of a first rotary shaft 2 such as a drive shaft, and an end of a second rotary shaft 4 such as a wheel-side rotary shaft. And a tripod 5 fixed to the part.
[0003]
A concave groove 6 extending in the axial direction of the housing 3 is formed on the inner peripheral surface of the housing 3 at a position equally divided in the circumferential direction. On the other hand, the tripod 5 is composed of a boss 7 for fixing to the end of the second rotary shaft 4, and a cylindrical trunnion journal 8 protruding in the radial direction from a position at which the boss 7 is equally divided in the circumferential direction. You. Each trunnion journal 8 supports a roller 9 via a needle roller 10 so as to be rotatable and slightly displaceable in the axial direction. The tripod type constant velocity universal joint 1 is formed by fitting these rollers 9 into the concave grooves 6 of the housing 3. A pair of guide surfaces 6a constituting each groove 6 is an arc-shaped concave surface, and each roller 9 is supported between these pair of guide surfaces 6a so as to roll and swing freely.
[0004]
When the tripod type constant velocity universal joint 1 configured as described above is used, for example, when the first rotary shaft 2 rotates, the rotational force is transmitted from the housing 3 via the roller 9, the needle roller 10, and the trunnion journal 8 to the tripod. 5 and the second rotating shaft 4 is rotated. When the central axis of the first rotary shaft 2 and the central axis of the second rotary shaft 4 do not match, that is, when the tripod-type constant velocity universal joint 1 takes an operating angle, the two rotary shafts 2, As shown in FIGS. 11 and 12, each of the trunnion journals 8 is displaced with respect to the corresponding guide surface 6a of the corresponding groove 6 in the direction of swinging about the tripod 5, as the rotation of the trunnion journals 4 occurs. At this time, the rollers 9 supported by the trunnion journals 8 roll on the guide surfaces 6 a of the concave grooves 6 and are displaced in the axial direction of the trunnion journals 8. By these movements, as is well known, constant velocity between the first and second rotating shafts 2 and 4 is ensured.
[0005]
In the case of the tripod type constant velocity universal joint 1 configured and operated as described above, when the first and second rotating shafts 2 and 4 are rotated in a state where the operating angle is set, each roller 9 performs a complicated movement. . That is, each roller 9 moves while changing its direction in the axial direction of the housing 3 along the guide surface 6a, and is displaced in the axial direction of the trunnion journal 8. When each roller makes such a complicated movement, the relative displacement between the outer peripheral surface of each roller 9 and the guide surface 6a is not always smooth, and relatively large friction is generated between these two surfaces. As a result, in the case of a tripod-type constant velocity universal joint having a structure as shown in FIGS. 11 and 12, a third-order axial force per rotation is generated. It is known that vibration called shudder is generated in a remarkable case such as when a large torque is transmitted in a state of being installed in an automobile and having a large operating angle.
[0006]
[Patent Document 1]
JP-A-62-233522 (page 14, lower right column, line 14 to page 2, lower left column, line 17, FIGS. 7 and 8)
[Patent Document 2]
French Patent No. 2,752,890 (page 3, line 29 to page 6, line 11, FIGS. 2 and 3B)
[0007]
[Problems to be solved by the invention]
As means for solving the above problems, French Patent No. 2,752,890 discloses a structure as shown in FIG. That is, the roller (9a, 9b) is guided in parallel with the housing groove, and a spherical fitting structure capable of centering and swinging between the spherical inner peripheral surface of the inner roller 9a and the spherical outer peripheral surface of the trunnion journal 8. It is.
[0008]
Each trunnion journal 8 has two flat portions 8a perpendicular to the axis z of the tripod 5, as shown in FIG. The radius rt of the arc forming the spherical outer peripheral surface of the trunnion journal 8 is smaller than the radius of curvature C / 2 of the spherical inner peripheral surface of the inner roller 9a. When the inner roller 9a is assembled to the trunnion journal 8, the diameter A of the entrance of the inner roller 9a (smaller than the inner diameter C) is a projection A (α) on the diameter A of the spherical outer peripheral surface of the trunnion journal 8 on this diameter. By rotating the tripod 5 about its axis z relative to the inner roller 9a by an angle α greater than or equal to this.
[0009]
In the case of this structure, as shown by reference numeral 8b in FIG. 13B, a convex forging parting line protruding from the outer diameter surface of the trunnion journal 8 can be formed at the center of the load surface of the trunnion journal, so that grinding or the like is performed. Removal work is inevitable.
[0010]
SUMMARY OF THE INVENTION An object of the present invention is to provide a tripod type constant velocity universal joint which achieves both reduction of shudder when assembled to a vehicle, high durability and low cost. Therefore, the technical problem of the present invention is to eliminate the forging parting line removal processing of the trunnion journal, and to enable spherical fitting while securing a small clearance between the inner roller and the trunnion journal to be spherically fitted. It is to be.
[0011]
[Means for Solving the Problems]
The tripod-type constant velocity universal joint according to the present invention has an end portion of a first rotary shaft which is formed at one end side in the axial direction and has a concave groove 14a extending in the axial direction at a position equally divided in the circumferential direction on the inner peripheral surface. A hollow cylindrical housing 14 fixed to
A boss 16a fixed to the end of the second rotating shaft, and a tripod 16 including a trunnion journal 16b whose spherical end protrudes in a radial direction from a circumferentially trisection position of the boss 16a,
An inner roller 22 whose inner peripheral surface is swung freely around the spherical outer peripheral surface of the trunnion journal 16b, and an outer roller 26 supported on the outer peripheral surface of the inner roller 22 via a needle roller 24 so as to be rotatable and axially movable. And a roller assembly 20 comprising
The outer roller 26 is housed in the concave groove 14a of the housing 14 so as to be freely rollable in the axial direction of the housing. In the tripod type constant velocity universal joint 11 comprising the guide shoulder surface 14c for guiding the
By providing a relief 16e partially along the forged parting line 16d of the trunnion journal 16, the raised portion of the forged parting line 16d is retracted inward from the outer peripheral surface of the trunnion journal 16b.
[0012]
By providing the relief 16e, the raised portion of the forged parting line 16d does not protrude from the outer peripheral surface of the trunnion journal 16b. Therefore, the inner roller 22 and the trunnion journal can be removed without removing the forged parting line 16d (of the raised portion). 16b can be brought into contact with the spherical fitting surface, and the surface pressure is reduced. Therefore, according to the present invention, it is possible to provide a tripod type constant velocity universal joint that achieves both reduction in shudder when assembled to a vehicle, high durability, and low cost.
[0013]
The outer diameter of one end in the axial direction of the boss 16a of the tripod 16 may be chamfered (16c) larger than that of the other end, so that when the roller assembly 20 is inclined and assembled to the trunnion journal 16, the roller assembly 20 may be bent. Interference with the boss 16a can be prevented. Most of the torque transmission between the tripod 16 and the second rotating shaft is performed by the non-end portion of the second rotating shaft in the boss portion 16a. Therefore, the end portion of the second rotating shaft of the boss portion 16a is largely chamfered. Also, the strength of the boss is not reduced.
[0014]
When the angle at which the roller assembly 20 is inclined when assembling the roller assembly 20 to the trunnion journal 16b is θ, the projection maximum diameter φD of the trunnion journal 16b (including the forged parting line 16d) in the angle θ direction is determined by By setting the inner diameter φd to be equal to or smaller than the insertion-side inner diameter φd, the inner roller 22 can be assembled without elastically deforming the roller assembly 20 when the roller assembly 20 is assembled into the trunnion journal 16b. Therefore, according to this embodiment, the forging parting line removing step and the press-fitting step when assembling the roller assembly 20 to the trunnion journal 16b can be omitted. A notch is partially provided in the inner diameter of the inner roller 22 on the insertion side, the inner diameter of the notch is φd2, and the maximum projection diameter of the trunnion journal 16b (including the forging parting line 16d) in the angle θ direction is φD2. Then, φD2 <φd2 may be set.
[0015]
Assuming that the angle at which the roller assembly 20 starts to separate from the trunnion journal 16b is θ1, after attaching the rotating shafts (4, 4a) to the tripod kit (16, 20), the roller assembly 20 is moved to the angle θ2 (θ2 <θ1). It can be set so as to interfere with the rotation axis (4, 4a) when tilted. Here, a unit including the tripod 16 and the roller assembly 20 is referred to as a tripod kit. Further, the rotating shaft includes not only the rotating shaft 4 itself but also another member attached to the rotating shaft 4 such as a retaining ring 4a. By adopting such a configuration, the tripod 16 is assembled to the second rotating shaft 4 in the state of a unit including the tripod 16 and the roller assembly 20, that is, the tripod kit, and once the retaining ring 4a is mounted, the retaining ring 4a or The inner roller 22 cannot be tilted to the angle θ1 at which the inner roller 22 separates from the trunnion journal 16 due to interference with the rotating shaft 4, and the tripod kit (16, 20) and the rotating shaft 4 are in a unit handling state, so that handling is very easy. become.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0017]
First, a first embodiment will be described with reference to FIGS. The tripod-type constant velocity universal joint 11 of this embodiment is the same as that of FIGS. 11 and 12 described above as far as the basic structure is concerned, and is fixed to the end of the first rotary shaft such as the drive shaft. And a tripod 16 fixed to an end of a second rotary shaft such as a wheel-side rotary shaft.
[0018]
The housing 14 is formed integrally with the first rotating shaft, and has a concave groove 14a extending in the axial direction at a position on the inner peripheral surface that is equally divided in the circumferential direction. Each concave groove 14a is recessed radially outward from the inner peripheral surface of the housing 14, and has a pair of guide surfaces 14b facing in the circumferential direction. And a bottom surface connecting the surfaces 14b. The pair of guide surfaces 14b provide an orbit for guiding and rolling an outer roller 26 described later in the axial direction of the housing, and transmit torque between the outer roller 26 and the outer roller 26. Further, a guide shoulder surface 14c for guiding the rolling of the outer roller 26 is formed on a part of the bottom surface of the concave groove 14a. The guide shoulder surface 14c serves to maintain a posture parallel to the axial direction of the housing and smoothly roll when the outer roller 26 moves in the concave groove 14a.
[0019]
The tripod 16 includes a boss 16a and a trunnion journal 16b. The boss 16a is fixed to an end of the second rotation shaft. For example, a spline shaft formed on the second rotary shaft 4 and a spline hole formed on the boss 16a are fitted and positioned by the retaining ring 4a (see FIG. 6). The trunnion journal 16b protrudes in the radial direction from a circumferentially equal position of the boss 16a. The end of each trunnion journal 16b has a spherical shape.
[0020]
Each trunnion journal 16b supports a roller assembly 20. The roller assembly 20 is of a double roller type including an inner roller 22 and an outer roller 26 which are relatively rotatable via a needle roller 24. The inner peripheral surface of the inner roller 22 has a spherical shape having substantially the same radius of curvature as the spherical outer peripheral surface of the trunnion journal 16b. The spherical inner peripheral surface of the inner roller 22 is swingably supported around the spherical outer peripheral surface of the trunnion journal 16b.
[0021]
A needle roller 24 is interposed between the cylindrical outer peripheral surface of the inner roller 22 and the cylindrical inner peripheral surface of the outer roller 26. Therefore, the inner roller 22 and the outer roller 26 can relatively rotate and move in the axial direction. Needle roller retainers 26a and 26b are integrally formed by forming projections on both ends in the axial direction of the cylindrical inner peripheral surface of the outer roller 26, so that the number of parts can be reduced. That is, as shown, by forming the inner needle roller retainer 26a and the outer needle roller retainer 26b integrally with the outer roller 26, a roller assembly is constituted by only the three members of the inner roller 22, the needle roller 24 and the outer roller 26. can do. Of course, the needle roller retainers 26a and 26b can be integrated with the outer roller 26 only on one of the inside and the outside, and the other can use a separate retaining ring or the like (see FIG. 7).
[0022]
The outer roller 26 is housed in the concave groove 14a of the housing 14. A pair of guide surfaces 14b constituting each concave groove 14a has an arc shape substantially the same as the generatrix of the outer peripheral surface of the outer roller 26 in the cross section of the housing 14. Therefore, the outer roller 26 is rotatably supported between the pair of guide surfaces 14b.
[0023]
When the constant velocity universal joint configured as described above is used, for example, when the first rotating shaft rotates, the rotational force is transferred from the housing 14 to the tripod via the roller assembly 20 (22, 24, 26) and the trunnion journal 16b. The second rotation shaft is transmitted to the 16 bosses 16a. Further, when the center axis of the first rotation axis and the center axis of the second rotation axis do not match, in other words, in a state where the operating angle is set, each trunnion journal 16b corresponds with the rotation of both rotation axes. It is displaced in the direction of swinging about the tripod 16 with respect to the guide surface 14b of the concave groove 14a. At this time, the outer roller 26 supported by each trunnion journal 16b rolls on the guide surface 14b of the groove 14a and is displaced in the axial direction of the trunnion journal 16b. By these movements, as is well known, constant velocity between the first and second rotating shafts is ensured.
[0024]
As shown by reference numeral 16c in FIGS. 2A and 3, the outer diameter of the boss 16a on the other end surface of the boss 16a of the tripod 16 in the axial direction (left side in FIGS. 2A and 3) is set to the other end. It is larger than the end face. Accordingly, when the roller assembly 20 is assembled to the trunnion journal 16b, the roller assembly 20 can be largely tilted as shown by the imaginary line in FIG. 3, so that interference occurs only at two opposing positions receiving the load of the trunnion journal 16b. Therefore, the inner roller 22 can be assembled by being pushed by elastic deformation. Further, since the clearance 16e exists, an effect of reducing the interference margin can be obtained as compared with the case where the clearance 16e is not provided, and the amount of elastic deformation of the roller at the time of assembling by pushing can be reduced. The two positions (outside the load range) perpendicular to the load receiving position of the trunnion journal 16b may be flat surfaces or curved surfaces that escape to the smaller diameter side than the load position.
[0025]
According to the above structure, since torque is transmitted between the spherical inner peripheral surface of the inner roller 22 and the spherical outer peripheral surface of the trunnion journal 16b, the contact surface pressure is suppressed low, which is advantageous in terms of strength and durability. At the same time, it is possible to keep the major axis of the contact ellipse relatively small without increasing the play in the rotational direction, and to reduce the spin moment on the contact ellipse generated due to the swing of the trunnion journal. Accordingly, unnecessary contact of the concave groove 14a of the housing 14 with the guide shoulder surface 14c can be avoided, and the rolling direction of the roller assembly 20 is stabilized, the rolling resistance of the roller assembly 20 is small, and a low axial force tripod type or the like is used. It becomes possible to make it a speed universal joint. As described above, according to this embodiment, it is possible to provide a tripod-type constant velocity universal joint that achieves both low rolling resistance and high strength and high durability of the roller assembly.
[0026]
The outer peripheral surface of the trunnion journal 16b has a spherical shape that spherically fits with the spherical inner peripheral surface of the inner roller 22, but the raised portion of the forging parting line 16d is located inside the spherical outer peripheral surface indicated by the broken line in FIG. A relief 16e is provided partially along the forging parting line 16d so as not to retreat and project therefrom. For this reason, the step of removing the forging parting line 16d can be omitted, the cold forming surface can be used, and the cost can be reduced. In this case, the load area is small because the relief 16e cannot receive the load, but the load area is small because the trunnion journal 16b and the inner roller 22 are loaded in a wide range by spherical fitting. Thus, a sufficient load capacity can be maintained. FIG. 2 illustrates the case where the relief 16e is a flat surface, but may have a cylindrical surface or another curved surface (see FIGS. 4 and 6).
[0027]
In the case of this structure, the inner roller 22 is spherically fitted to the trunnion journal 16b, and is integrally supported in the axial direction of the trunnion journal 16b. Since the accompanying movement in the axial direction of the trunnion journal is allowed by rolling and sliding on the needle roller 24 disposed between the inner roller 22 and the outer roller 26, the internal friction force is low, and the roller has low rolling resistance. Have been.
[0028]
In the case of the prior art shown in FIG. 13A, when assembling the roller to the trunnion journal, the roller is inclined in a plane (corresponding to the plane in FIG. 1 of the present application) perpendicular to the plane of FIG. 3 of the present application. Therefore, in order to allow the roller to be largely inclined, it is necessary to reduce the outer diameter of the boss portion, that is, to reduce the thickness of the boss portion, or to lengthen the trunnion journal under the neck. However, if the outer diameter of the boss portion is reduced, the strength of the boss portion decreases, and if the trunnion journal is lengthened below the neck, a problem occurs in that the outer shape of the joint increases. The tripod-type constant velocity universal joint according to this embodiment avoids such a problem, and provides a tripod-type constant velocity universal joint that achieves both low rolling resistance and high strength / high durability, low cost and downsizing of the roller. Can be provided.
[0029]
Next, the second embodiment shown in FIGS. 4 and 5 has the same basic structure as the above-described first embodiment (FIGS. 1-3), except that the inner roller 22 is attached to the trunnion journal 16b. Assuming that the angle of inclination when assembling is θ, the projected maximum diameter φD of the trunnion journal 16b from the angle θ direction including the outermost diameter portion of the protruding part of the forging parting line 16d is the inner diameter of the inner roller 22 on the fitting insertion side. It is set smaller than φd. A notch is partially provided in the inner diameter of the inner roller 22 on the insertion side, the inner diameter of the notch is φd2, and the maximum projection diameter of the trunnion journal 16b (including the forging parting line 16d) in the angle θ direction is φD2. Then, φD2 <φd2 may be set. Accordingly, when the roller assembly 20 is assembled into the trunnion journal 16b, the inner roller 22 can be assembled without being elastically deformed. Therefore, according to this embodiment, the forging parting line removing step and the press-fitting step when assembling the roller assembly 20 to the trunnion journal 16b can be omitted.
[0030]
The third embodiment shown in FIG. 6 has the same basic structure as the above-described second embodiment (FIG. 4), except that the inner roller 22 is tilted with respect to the trunnion journal 16b so that the inner roller Assuming that the angle at which the inner roller 22 deviates from the trunnion journal 16b is θ1, when the angle of the inner roller 22 becomes an angle θ2 slightly smaller than θ1, the outer roller 26 rotates the second rotating shaft 4 or the second rotating shaft. The dimensions are set so as to interfere with the retaining ring 4a on which the shaft is mounted. By adopting such a configuration, the tripod 16 is assembled to the second rotating shaft 4 in the state of a unit including the tripod 16 and the roller assembly 20, that is, the tripod kit, and once the retaining ring 4a is mounted, the retaining ring 4a or The inner roller 22 cannot tilt to the angle θ1 at which the inner roller 22 separates from the trunnion journal 16 due to interference with the second rotating shaft 4, and the tripod kit (16, 20) and the rotating shaft 4 are in a unit handling state, and handling is performed. It will be very easy.
[0031]
In the fourth embodiment shown in FIG. 7, the basic structure is as described in the first embodiment (FIG. 1-3), the second embodiment (FIG. 4), or the third embodiment (FIG. 4). This is the same as FIG. 6), but separate needle stoppers (25a, 25b) are provided at both axial ends of the cylindrical inner peripheral surface of the outer roller 26. That is, as the retaining of the needle roller 24, an annular retainer 25a and a retaining ring 25b attached to an annular retaining ring groove formed on the inner peripheral surface at both axial ends of the outer roller 26 are employed.
[0032]
The basic structure of the fifth embodiment shown in FIG. 8 is the same as that of the first embodiment (FIG. 1-3), the second embodiment (FIG. 4) or the third embodiment (FIG. Same as 6), except that needle retainers 22a and 22b are integrally formed by providing protrusions on both ends in the axial direction of the cylindrical outer peripheral surface of the inner roller 22. Thereby, there is an effect that the number of parts can be reduced. That is, as shown in the drawing, by forming both the inner needle roller retainer 22a and the outer needle roller retainer 22b integrally with the inner roller 22, the roller assembly 20 can be formed by only the three members of the inner roller 22, the needle roller 24, and the outer roller 26. Can be configured. The needle roller retainers 22a and 22b may be integrated with the inner roller 22 only on one of the inner side and the outer side, and the other may use a separate retaining ring or the like.
[0033]
The sixth embodiment shown in FIG. 9 has the same basic structure as the above-described first embodiment (FIGS. 1-3), except that the inner diameter of the inner needle roller retainer 26a of the outer roller 26 is φDi. The difference is that when the outer diameter of the inner roller 22 is φdo, the relationship φDi <φdo is set. In this embodiment, since the relationship φDi <φdo is set, the outer roller 26 is less likely to be disassembled from the inner roller 22 in the state of the tripod kit (16, 20). Further, by setting the needle roller 24 so as not to interfere with the boss portion 16a of the tripod 16 even when the outer roller is lowered in FIG. 9, the handling is further facilitated.
[0034]
The seventh embodiment shown in FIG. 10 has the same basic structure as the above-described fifth embodiment (FIG. 8), except that the outer diameter of the outer needle roller retainer 22b of the inner roller 22 is φdo, When the inner diameter of the outer roller 26 is φDi, the difference is that the relationship φDi <φdo is set. In this embodiment, since the relationship of φDi <φdo is set, the outer roller 26 is less likely to be separated from the inner roller 22 in the state of the tripod kit (16, 20), so that handling is facilitated.
[0035]
【The invention's effect】
As described above, by mounting the tripod-type constant velocity universal joint according to the present invention on a vehicle, vibration of the vehicle can be reduced and a low-cost tripod-type constant velocity universal joint having both high strength and high durability can be achieved. Can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a tripod type constant velocity universal joint for describing an embodiment of the present invention.
FIG. 2A is a side view of a trunnion journal,
(B) is a cross-sectional view of the trunnion journal,
FIG. 2C is an enlarged view of a forging parting line convex portion in FIG.
FIG. 3 is an exploded sectional view of the tripod kit shown in FIG. 1;
FIG. 4 is an exploded cross-sectional view of a tripod kit similar to FIG. 3 showing a second embodiment,
FIG. 5A is a cross-sectional view of an inner roller,
FIG. 5B is a view taken in the direction of the arrow Y in FIG.
FIG. 6 is a sectional view of a tripod kit showing a third embodiment.
FIG. 7 is a cross-sectional view of a roller assembly according to a fourth embodiment.
FIG. 8 is a cross-sectional view of a roller assembly according to a fifth embodiment.
FIG. 9 is a cross-sectional view of a roller assembly according to a sixth embodiment.
FIG. 10 is a cross-sectional view of a roller assembly according to a seventh embodiment.
FIG. 11 is a perspective view of a conventional tripod type constant velocity universal joint.
FIG. 12 is a longitudinal sectional view of a conventional tripod type constant velocity universal joint.
FIG. 13A is a sectional view of a tripod type constant velocity universal joint showing a conventional technique,
(B) is a sectional view of the trunnion journal.
[Explanation of symbols]
11 tripod type constant velocity universal joint 14 housing 14a concave groove 14b guide surface 14c guide shoulder surface 16 tripod 16a boss 16b trunnion journal 16c chamfer 16d forged parting line 16e relief 20 roller assembly 22 inner roller 22a inner needle roller retainer 22b outer needle roller Retainer 24 Needle roller 25a Retainer 25b Retaining ring 26 Outer roller 26a Inner needle roller retainer 26b Outer needle roller retainer

Claims (4)

A hollow cylindrical housing fixed to the end of the first rotating shaft, which is formed at one end in the axial direction and has a concave groove extending in the axial direction at a position equally divided in the circumferential direction on the inner peripheral surface,
A boss fixed to the end of the second rotating shaft, and a tripod consisting of a spherical trunnion journal whose end protruding in the radial direction from a circumferentially equal position of the boss,
A roller assembly including an inner roller whose inner peripheral surface is swingably fitted to the spherical outer peripheral surface of the trunnion journal, and an outer roller supported on the outer peripheral surface of the inner roller via a needle roller so as to be rotatable and axially movable. Has,
The outer roller is housed in a concave groove of the housing so as to freely roll in the axial direction of the housing, and the guide groove receives the load by contacting the outer peripheral surface of the outer roller with the concave groove, and a guide shoulder surface for guiding the outer roller in the axial direction of the housing. In the tripod type constant velocity universal joint consisting of
A tripod-type constant velocity universal joint characterized in that a relief is provided partially along a forged parting line of a trunnion journal so that a protruding portion of the parting line is retreated inside the outer peripheral surface of the trunnion journal. The outer diameter of one end of the tripod boss in the axial direction is larger than that of the other end so that the roller assembly does not interfere with the boss when the roller assembly is inclined and assembled to the trunnion journal. Item 3. A tripod type constant velocity universal joint according to item 1. When the angle at which the roller assembly is inclined when the roller assembly is assembled to the trunnion journal is θ, the maximum projected diameter of the trunnion journal in the angle θ direction including the forging parting line portion is equal to or less than the inner diameter of the inner roller insertion side. The tripod type constant velocity universal joint according to claim 1 or 2, wherein Assuming that the angle at which the roller assembly starts to separate from the trunnion journal is θ1, after setting the rotation shaft to the tripod kit, if the roller assembly is tilted to an angle θ2 (θ2 <θ1), it is set so as to interfere with the rotation shaft. The tripod type constant velocity universal joint according to any one of claims 1 to 3, wherein:

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