Tripod type constant velocity universal joint

Abstract

The goal is to reduce the cost of tripod-type constant velocity universal joints while ensuring sufficient roller retention force and sliding range. [Solution] The tripod-type constant velocity universal joint 1 has three arc-shaped large-diameter portions 22 and three arc-shaped small-diameter portions 23 alternately provided on the inner diameter surface 21 of the cup portion 20 of the outer joint member 2 in the joint circumferential direction Z, a track groove 5 is formed on the inside of the large-diameter portion 22 in the joint radial direction Y, the large-diameter portion 22 and the small-diameter portion 23 are connected via a roller guide surface 6, and the roller is prevented from coming off by a clip 10 mounted in an arc-shaped clip mounting groove 25 formed on the opening end of the cup portion 20. The clip 10 protrudes from the roller guide surface 6 at both ends of the clip mounting groove 25 in the joint circumferential direction Z, and a retaining portion 10c that can contact the outer diameter surface of the roller is provided on the part of the clip 10 located outside the clip mounting groove 25, and this retaining portion 10c extends parallel to the axis of the leg shaft 32 and is arranged along the roller guide surface 6.

Description

Technical Field

[0001] The present invention relates to a tripod constant velocity joint.

Background Art

[0002] A constant velocity joint has a structure that connects two shafts on the driving side and the driven side and can transmit torque at a constant speed even when these two shafts take an operating angle (i.e., relatively angularly displaced). This constant velocity joint is roughly classified into a fixed type that allows only the relative angular displacement of the two shafts and a sliding type that allows the relative angular displacement and axial displacement of the two shafts. For example, in a drive shaft used to transmit the power output from a drive source such as an engine or a motor mounted on an automobile chassis to a drive wheel, a sliding constant velocity joint is provided on the inboard side (drive source side), and a fixed constant velocity joint is provided on the outboard side (drive wheel side).

[0003] As a sliding constant velocity joint, a tripod constant velocity joint is known. The tripod constant velocity joint has a bottomed cylindrical cup portion with one end open in the joint axis direction (the direction along the axis of the constant velocity joint), and three track grooves extending in the joint axis direction are formed on the inner circumference of this cup portion. It includes an outer joint member, a roller that is housed in each track groove and rolls along a pair of roller guide surfaces facing each other in the joint circumferential direction (the circumferential direction of a circle centered on the axis of the constant velocity joint), and a tripod member having three leg shafts that rotatably support the roller. This tripod constant velocity joint has a retaining structure for retaining the roller (joint internal components including the roller and the tripod member that rotatably supports the roller). For example, in the tripod constant velocity joint described in Patent Document 1 below, a clip as a retaining part is attached to the opening side end of the cup portion to retain the roller.

[0004] An overview of a conventional roller retaining structure disclosed in Patent Document 1 will be explained with reference to Figure 6. First, on the inner diameter surface of the cup portion 100A of the outer joint member 100, three large-diameter portions 101 and three small-diameter portions 102 are alternately provided in the joint circumferential direction Z, and the large-diameter portions 101 and small-diameter portions 102 are connected via a roller guide surface 103 that guides the outer diameter surface of the roller 121. In the area where the small-diameter portion 102 is formed at the opening end of the cup portion 100A, a chamfer (first chamfer) 104 is formed to allow relative angular displacement between the outer joint member 100 and the tripod member 120 (to avoid interference of the shaft connected to the tripod member 120), and second chamfers 105 are formed on both sides of this first chamfer 104 in the joint circumferential direction Z. The first chamfer 104 is provided with an arc-shaped clip mounting groove 106 that extends in the circumferential direction Z of the joint, and the circumferential end of this clip mounting groove 106 opens into the second chamfer 105.

[0005] On the other hand, the clip 110 integrally comprises an arc portion 111 positioned along the large diameter portion 101, a mounting portion 112 that fits into the clip mounting groove 105, and a retaining portion 113 provided between the arc portion 111 and the mounting portion 112. In this case, when the arc portion 111 of the clip 110 is positioned along the large diameter portion 101 of the cup portion 100A, and the mounting portion 112 of the clip 110 is fitted into the clip mounting groove 106 of the cup portion 100, the retaining portion 113 is positioned so that, when viewed from the direction of the coupling axis, it overlaps with a part of the roller 121 inserted into the track groove (large diameter portion 101). As a result, when the roller 121 moves to the opening side of the cup portion 100A, the outer diameter surface of the roller 121 comes into contact with the retaining portion 113 of the clip 110, thus preventing the internal coupling components, including the roller 121, from coming loose.

[0006] The above-mentioned anti-loosening structure offers the following advantages. Since the second chamfer 105 is provided on both sides of the first chamfer 104 in the circumferential direction of the joint, the circumferential dimensions of the first chamfer 104 and the clip mounting groove 106 provided therein can be shortened. This improves the machinability of the clip mounting groove 106 and the ease with which the clip 110 can be attached to the clip mounting groove 106. The presence of the second chamfer 105 improves the ease of inserting the roller 121 into the roller guide surface 103 (the ease of assembling the internal components of the joint into the cup portion 100A).

[0007] Furthermore, in the case of the retaining structure described above, which is provided with the second chamfer 105, the clip 110 contacts the cup portion 100A at point P1. In this case, the retaining portion 113 of the clip 110 is positioned at the location shown by the solid line in Figure 6. On the other hand, when the second chamfer 105 is not provided, the clip 110 contacts the cup portion 100A at point P2. In this case, the retaining portion 113 of the clip 110 is positioned at the location shown by the dashed line in Figure 6, that is, closer to the rotation center of the roller 121 than when the second chamfer 105 is provided. Therefore, in the case of the retaining structure provided with the second chamfer 105, the roller 121 interferes with the retaining portion 113 of the clip 110 when the amount of protrusion of the roller 121 from the opening of the cup portion 100A (the amount of protrusion in the joint axis direction) becomes larger compared to when the second chamfer 105 is not provided. Therefore, it also offers the advantage of being able to secure a large amount of sliding of the roller 121 in the axial direction of the joint (the allowable axial displacement of the tripod-type constant velocity universal joint). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2002-168262 [Overview of the project] [Problems that the invention aims to solve]

[0009] To provide the second chamfer 105 described above, for example, additional machining such as cutting could be performed during the manufacturing process of the outer joint member 100, but this would inevitably lead to increased costs due to a deterioration in product yield and an increase in the number of processes. The second chamfer 105 can also be formed by plastic deformation such as cold forging (paragraph 0025 of Patent Document 1), but in this case, it would be necessary to manufacture and possess a large number of punches corresponding to the shape of the second chamfer 105 and the axial length of the cup portion 100A, which would increase equipment (mold) costs.

[0010] Therefore, the present invention aims to ensure the required roller retention force and sliding amount in the axial direction of the joint while suppressing the cost increase of tripod-type constant velocity universal joints. [Means for solving the problem]

[0011] The present invention, devised to achieve the above objectives, The device comprises an outer joint member having a bottomed cylindrical cup portion with one end open in the joint axis direction, and three track grooves extending in the joint axis direction and formed at equal intervals in the circumferential direction of the joint on the inner circumference of the cup portion, and a tripod member having three leg shafts that rotatably support the rollers, On the inner diameter surface of the cup portion, three large-diameter and three small-diameter portions are alternately provided in the circumferential direction of the joint, a track groove is formed on the inner side of the large-diameter portion in the radial direction of the joint, and the large-diameter and small-diameter portions are connected via a roller guide surface. In a tripod-type constant velocity universal joint, a clip mounting groove extending in the circumferential direction of the joint is formed at the opening end of the cup portion where a small diameter portion is provided, and the roller is prevented from coming off by a clip mounted in this clip mounting groove, The clips protrude from the roller guide surface at both ends of the clip mounting groove in the circumferential direction of the joint. The clip is characterized in that a retaining portion is provided on the part of the clip located outside the clip mounting groove, which can come into contact with the outer diameter surface of the roller, and this retaining portion extends parallel to the axis of the leg shaft and is arranged along the roller guide surface.

[0012] In the tripod-type constant velocity universal joint according to the present invention, clips for preventing the roller (and the tripod member that rotatably supports it) from coming off protrude from the roller guide surface at both ends of the clip mounting groove in the joint circumferential direction. This means that both ends of the clip mounting groove in the joint circumferential direction are open to the roller guide surface, and the outer joint member does not have a portion corresponding to the second chamfer 105 (see Figure 6) provided in conventional tripod-type constant velocity universal joints (Patent Document 1). In this case, additional processing such as cutting or forming punches that would be necessary when additionally providing a second chamfer are not required, so processing costs can be reduced. Furthermore, if there is no portion corresponding to the second chamfer, the groove length of the clip mounting groove and, consequently, the contact area of ​​the clip with the clip mounting groove (outer joint member) can be increased, so the roller retention force can be increased.

[0013] Furthermore, the retaining portion of the clip, located outside the clip mounting groove and capable of contacting the outer diameter surface of the roller, extends parallel to the axis of the leg shaft and is positioned along the roller guide surface. With this configuration, it is possible to increase the amount of roller protrusion from the open end face of the outer joint member (cup portion), thereby ensuring a larger amount of roller sliding in the joint axial direction.

[0014] The retaining portion of the clip is preferably in contact with the outer diameter surface of the roller at the end in the torque transmission direction when the roller is viewed from the coupling axis direction. This allows the amount of sliding of the roller in the coupling axis direction to be maximized. [Effects of the Invention]

[0015] Based on the above, the present invention makes it possible to realize a tripod-type constant velocity universal joint that can sufficiently secure the roller's retaining force and sliding amount while suppressing the cost increase of the tripod-type constant velocity universal joint. [Brief explanation of the drawing]

[0016] [Figure 1]It is a longitudinal sectional view in the state of the operating angle of 0° of a tripod constant velocity joint according to an embodiment of the present invention. [Figure 2] It is a left side view of FIG. 1 (front view of a tripod constant velocity joint). [Figure 3] It is a partially enlarged view when FIG. 1 is viewed from the direction of arrow A in the figure. [Figure 4] It is a plan view of a clip in a free state. [Figure 5] (a) The figure shows a state where a roller abuts on a clip in the tripod constant velocity joint of this embodiment, and (b) the figure shows a state where a roller abuts on a clip in a conventional tripod constant velocity joint. [Figure 6] It is a figure which expands and shows a part of the retaining structure of the roller employed by the conventional tripod constant velocity joint.

Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described based on the drawings (FIGS. 1 to 5). In the following description, the direction along the axis of the tripod constant velocity joint 1 is referred to as the "joint axis direction", and the radial direction and circumferential direction of a circle centered on the axis of the tripod constant velocity joint 1 are referred to as the "joint radial direction" and "joint circumferential direction", respectively. In FIGS. 1 and the like, the joint axis direction, joint radial direction, and joint circumferential direction are indicated by arrow X, arrow Y, and arrow Z, respectively. The joint circumferential direction Z is also the "torque transmission direction" of the tripod constant velocity joint 1.

[0018] FIG. 1 is a longitudinal sectional view of a tripod constant velocity joint 1 according to an embodiment of the present invention in a state where the operating angle is 0°, FIG. 2 is a left side view (front view) of FIG. 1, and FIG. 3 is a view of a part of FIG. 1 as seen from the direction of arrow A in the figure. The tripod constant velocity joint 1 shown in FIG. 1 and the like is a type of sliding constant velocity joint that allows angular displacement and axial displacement of two shafts on the driving side and the driven side, and constitutes a drive shaft by being connected to a fixed constant velocity joint (not shown) via a shaft 8 (see the broken line in FIG. 1). The drive shaft is mounted, for example, on an automobile and transmits the rotational torque output from a drive source such as an engine or an electric motor mounted on the vehicle body to the drive wheels. In this drive shaft, the tripod constant velocity joint 1 is arranged on the drive source side (inboard side), and the fixed constant velocity joint is arranged on the drive wheel side (outboard side). In FIG. 1, the left side of the paper surface is the drive wheel side, and the right side of the paper surface is the drive source side.

[0019] As shown in FIGS. 1 to 3, the tripod constant velocity joint 1 (hereinafter, also simply referred to as "constant velocity joint 1") includes an outer joint member 2, a tripod member 3 as an inner joint member, a roller unit 4 as a torque transmission member, and a clip 10 as a retaining part.

[0020] The outer joint member 2 has a bottomed cylindrical cup portion 20 with one end open in the joint axis direction X and the other end closed. Three linear track grooves 5 extending in the joint axis direction X are formed on the inner diameter surface 21 of the cup portion 20 at equal intervals in the joint circumferential direction Z. In this embodiment, the inner diameter surface 21 of the cup portion 20 is formed in a flower shape with three alternating arc-shaped large diameter portions 22 extending in the joint circumferential direction Z and three arc-shaped small diameter portions 23 located inside the joint radial direction Y from the large diameter portion 22, and the groove bottom surface of the track groove 5 is composed of the above-mentioned large diameter portion 22. Each track groove 5 extends in the joint axis direction X and has a pair of roller guide surfaces 6 arranged opposite each other in the joint circumferential direction Z, and the above-mentioned large diameter portion 22 and small diameter portion 23 are continuous via the roller guide surfaces 6. In this embodiment, the outer diameter surface of the cup portion 20, like the inner diameter surface 21, has a flower-like shape in which three arc-shaped large-diameter portions extending in the joint circumferential direction Z and three arc-shaped small-diameter portions located inside the joint radial direction Y from the large-diameter portions are alternately provided in the joint circumferential direction Z.

[0021] The tripod member 3 integrally comprises a body portion 31 having a central hole 30, and three leg shafts 32 that protrude outward in the joint radial direction Y from three equal divisions in the joint circumferential direction Z on the outer diameter surface of the body portion 31, with their tip surfaces facing the groove bottom surface (large diameter portion 22) of the track groove 5 through a small gap in the joint radial direction Y. A female spline is formed in the central hole 30 of the body portion 31, and the tripod member 3 and the shaft 8 are coupled in a torque-transmitting manner by fitting a male spline formed on the shaft 8 into this female spline. Although not shown in the figure, a retaining ring is attached to the outer circumference of the shaft 8, and the shaft 8 is prevented from coming out of the tripod member 3 by locking this retaining ring onto the tripod member 3 in the direction of withdrawal of the shaft 8.

[0022] There are a total of three roller units 4, each individually housed in a track groove 5 of the three outer joint members 2. In this embodiment, the pair of roller guide surfaces 6 provided in the track groove 5 are formed as a concave curved surface, with the approximately central part in the joint radial direction Y slightly recessed relative to the axis of the opposing leg shaft 32 in the joint circumferential direction Z compared to both ends in the joint radial direction Y. The outer diameter surface of the roller unit 4 (outer diameter surface 15 of the outer ring 11) facing this roller guide surface 6 is formed as a convex curved surface that makes angular contact with the concave curved roller guide surface 6. As a result, when an axial force in the joint axial direction X acts on the outer joint member 2 or the shaft 8, the roller unit 4 housed in the track groove 5 rolls along the roller guide surface 6.

[0023] The roller unit 4 is a so-called double roller type and comprises an outer ring 11 as a "roller" forming an annular shape around the axis of the leg shaft 32, an annular inner ring 12 arranged on the inner circumference of the outer ring 11 and fitted onto the outer circumference of the leg shaft 32, and rolling elements interposed between the outer ring 11 and the inner ring 12. In this embodiment, a large number of needle rollers 13 in a full-roller state without cages are used as rolling elements. The needle rollers 13 are arranged to roll freely between the inner diameter surface of the cylindrical outer ring 11, which serves as the outer raceway surface, and the outer diameter surface of the cylindrical inner ring 12, which serves as the inner raceway surface. Therefore, the outer ring 11 and the inner ring 12 can rotate relative to each other via the large number of needle rollers 13. Snap rings 14 are arranged on the outer and inner sides of the needle rollers 13 in the coupling radial direction Y, respectively. This snap ring 14 prevents unintended disassembly of the roller unit 4 (falling off the needle rollers 13).

[0024] As shown in Figure 3, the outer diameter surface (cross-sectional shape) of the leg shaft 32 is elliptical with the coupling axis direction X as the minor axis and the coupling circumferential direction (torque transmission direction) Z as the major axis, while the inner diameter surface of the inner ring 12 fitted to the outer circumference of the leg shaft 32 is formed in an arc-shaped convex cross section. Therefore, the outer diameter surface of the leg shaft 32 contacts the inner diameter surface of the inner ring 12 at both ends in the direction perpendicular to the coupling axis direction X (coupling circumferential direction Z), and a gap G in the coupling axis direction X is formed between it and the inner diameter surface of the inner ring 12. Furthermore, as described above, the roller unit 4 is an assembly in which the inner ring 12 and the outer ring 11 can rotate relative to each other via a number of needle rollers 13. With the above configuration, the outer ring 11 and the inner ring 12 (including the roller unit 4) are movable in the axial direction (coupling radial direction Y) of the leg shaft 32 and are also pivotable relative to the leg shaft 32. In other words, the axes of the outer ring 11 and the inner ring 12 can be inclined with respect to the axis of the leg axis 32 within a plane that includes the axis of the leg axis 32.

[0025] Therefore, when the constant velocity universal joint 1 takes an operating angle, the axis of the tripod member 3 is inclined with respect to the axis of the outer joint member 2, but it is possible to avoid the outer ring 11 (including the roller unit 4) and the roller guide surface 6 being at an oblique angle. As a result, a low-vibration constant velocity universal joint 1 can be realized with reduced induced thrust (axial force induced by friction between internal joint components) and sliding resistance.

[0026] The following describes the roller retention structure, which is a characteristic feature of the present invention. In short, the outer ring 11 (including the roller unit 4) as a roller is retained from coming off by a clip 10 attached to the opening end of the cup portion 20 of the outer joint member 2.

[0027] As shown in Figures 1 and 2, chamfers 24 are formed in the area where three small-diameter portions (arc-shaped small-diameter inner diameter surfaces) 23 are formed, spaced apart in the circumferential direction Z of the joint, on the opening end of the cup portion 20 of the outer joint member 2. That is, the cup portion 20 has a tapered surface that slopes downward from its opening end face toward the small-diameter portions 23. The primary function of the chamfers 24 is to prevent the shaft 8 connected to the tripod member 3 from interfering with the outer joint member 2 when the constant velocity universal joint 1 takes a predetermined operating angle (when the outer joint member 2 and the tripod member 3 are relatively angularly displaced).

[0028] Each chamfer 24 has an arc-shaped clip mounting groove 25 extending in the joint circumferential direction Z, and one end and the other end of the clip mounting groove 25 in the joint circumferential direction Z open to the roller guide surfaces 6 on both sides of the small diameter portion 23 (chamfer 24) in the joint circumferential direction Z. The outer joint member 2 of this embodiment does not have the second chamfer 105 (or a corresponding portion) that was provided on the conventional outer joint member 100 shown in Figure 6.

[0029] The clip 10 shown in Figure 4 has an arc portion 10a, a mounting portion 10b, and a retaining portion 10c that extends substantially parallel to the axis of the leg shaft 32 (joint radial direction Y) to connect the arc portion 10a and the mounting portion 10b. The clip 10 is a metal part obtained by bending and folding a single metal wire, and a discontinuing portion 10d is provided at one location in the joint circumferential direction Z (in this case, one of the three mounting portions 10b provided) to make the clip 10 discontinuous in the joint circumferential direction Z. Due to the presence of this discontinuing portion 10d, the clip 10 as a whole can be elastically deformed to reduce its diameter.

[0030] The clip 10 is attached to the outer joint member 2 by first applying pressure in the diameter-reducing direction to the clip 10, which is in a state of elastic diameter-reduced deformation, and then placing it on the inner circumference of the cup portion 20. After that, the pressure is released to cause elastic diameter-expanding deformation, and each mounting portion 10b of the clip 10 is fitted into the corresponding clip mounting groove 25. For this reason, the "part of the clip located outside the clip mounting groove" as referred to in this invention is the part other than the mounting portion 10b.

[0031] When the clip 10 is attached to the outer joint member 2, as shown in Figure 2, the arc portion 10a is positioned close to the inside of the large diameter portion 22 in the joint radial direction Y along the large diameter portion 22 of the cup portion 20, and the retaining portion 10c is positioned close to the inside of the roller guide surface 6 (the side closer to the axis of the leg shaft 32) along the roller guide surface 6. In this embodiment, the outer joint member 2 is not provided with a portion corresponding to the conventional second chamfer 105 (see Figure 6), and one end and the other end of the clip mounting groove 25 in the joint circumferential direction Z open to the roller guide surfaces 6 on both sides of the chamfer 24 in the joint circumferential direction Z. As a result, the clip 10 attached to the outer joint member 2 protrudes from the roller guide surface 6 towards the track groove 5 at both ends of the clip mounting groove 25 in the joint circumferential direction Z.

[0032] As described above, in the tripod-type constant velocity universal joint 1 of this embodiment, the clip 10 for preventing the roller unit 4 from coming off protrudes from the roller guide surface 6 at both ends of the clip mounting groove 25 in the joint circumferential direction Z. This means that one end and the other end of the clip mounting groove 25 in the joint circumferential direction Z are open to the roller guide surface 6, and the outer joint member 2 does not have a portion corresponding to the second chamfer 105 shown in Figure 6. In this case, additional processing such as cutting and forming punching that would be required when the outer joint member 2 is additionally provided with a second chamfer is not necessary, so the processing cost of the outer joint member 2, and consequently the manufacturing cost of the constant velocity universal joint 1, can be reduced. Furthermore, if there is no portion corresponding to the second chamfer, the groove length of the clip mounting groove 25 and consequently the contact area of ​​the clip 10 with the outer joint member 2 on which the clip mounting groove 25 is provided can be increased, thereby increasing the anti-dislodgement force of the roller unit 4.

[0033] Furthermore, as shown in Figure 2 and the lower view of Figure 5(a), the retaining portion 10c (the entire portion) of the clip 10, which is located outside the clip mounting groove 25 of the outer joint member 2 and is capable of contacting the outer diameter surface of the roller unit 4 (outer roller 11), extends parallel to the axis of the leg shaft 32 (joint radial direction Y) and is positioned along the roller guide surface 6. In particular, in this embodiment, the entire retaining portion 10c of the clip 10 is positioned close to the roller guide surface 6 such that the retaining portion 10c of the clip 10 contacts the outer diameter surface of the roller unit 4 at the end in the torque transmission direction when the roller unit 4 is viewed from the joint axis direction.

[0034] With this configuration, compared to, for example, the case where a different configuration from the present invention is adopted, such as the lower diagram of Figure 5(b) (in this case, a configuration using a clip 10' with the retaining portion inclined with respect to the radial direction Y of the joint), the contact point between the roller unit 4 and the retaining portion 10c of the clip 10 can be shifted closer to the roller guide surface 6, thereby increasing the amount of protrusion of the roller (roller unit 4) from the open end face of the outer joint member 2. In other words, the amount of protrusion D shown in the upper diagram of Figure 5(a) is greater than the amount of protrusion D' shown in the upper diagram of Figure 5(b) (D>D'). As a result, the amount of sliding of the internal joint components, including the roller unit 4, in the joint axis direction X, or in other words, the relative displacement amount between the outer joint member 2 and the internal joint components in the joint axis direction X, can be increased.

[0035] In this case, even if the length of the cup portion 20 of the outer joint member 2 in the joint axis direction X is shortened, the required relative displacement amount can be secured. Therefore, it becomes possible to realize a lightweight and compact tripod-type constant velocity universal joint 1 in which the outer joint member 2 is shortened in the joint axis direction X.

[0036] The above describes a tripod-type constant velocity universal joint 1 according to one embodiment of the present invention, but the embodiments of the present invention are not limited thereto.

[0037] For example, the tripod-type constant velocity universal joint 1 described above employs a double-roller type roller unit 4 equipped with an outer ring 11 and an inner ring 12 that rotate relative to each other via a large number of needle-shaped rollers 13. However, the present invention can also be applied to a tripod-type constant velocity universal joint 1 employing a single-roller type roller unit. Although not shown in the figures, the single-roller type roller unit is a type of unit in which the inner ring 12 of the double-roller type is omitted, and comprises, for example, a roller fitted on the outer circumference of the leg shaft 32 and a large number of rolling elements (needle-shaped rollers) arranged between the roller and the leg shaft 32.

[0038] Furthermore, although the outer joint member 2 described above has a so-called flower-shaped outer diameter surface of the cup portion 20, the present invention can also be applied to a tripod-type constant velocity universal joint 1 using an outer joint member 2 in which the outer diameter surface of the cup portion 20 is formed in a cylindrical shape (without irregularities).

[0039] Furthermore, the tripod-type constant velocity universal joint 1 of this embodiment, as described above, can be used not only in drive shafts for automobiles but also in power transmission paths for industrial machinery and the like. [Explanation of Symbols]

[0040] 1. Tripod type constant velocity universal joint 2. Outer joint member 3. Tripod Member 4 Roller Units 5 Track grooves 6. Roller guide surface 10 clips 10a Arc section 10b Mounting part 10c Retaining part 11 Outering (Laura) 20 cup section 22 Large diameter section 23 Small diameter section 24 Chamfering 25 clip mounting grooves 32 Leg axis X joint axial direction Y joint radial direction Z-joint circumferential direction (torque transmission direction)

Claims

1. An outer joint member having a bottomed cylindrical cup portion with one end open in the joint axis direction, and three track grooves extending in the joint axis direction formed on the inner circumference of the cup portion at equal intervals in the joint circumferential direction, a tripod member having three leg shafts that rotatably support the rollers, and a roller housed in each track groove and rolling along a pair of opposing roller guide surfaces in the joint circumferential direction On the inner diameter surface of the cup portion, three large-diameter portions and three small-diameter portions are alternately provided in the circumferential direction of the joint, the track groove is formed on the inner side of the large-diameter portion in the radial direction of the joint, and the large-diameter portion and the small-diameter portion are connected via the roller guide surface. In a tripod-type constant velocity universal joint, a clip mounting groove extending in the circumferential direction of the joint is formed at the opening end of the cup portion where the small diameter portion is provided, and the roller is prevented from coming off by a clip mounted in this clip mounting groove, The clip protrudes from the roller guide surface at both ends of the clip mounting groove in the joint circumferential direction, A tripod-type constant velocity universal joint, characterized in that a retaining portion is provided in the part of the clip located outside the clip mounting groove, which is capable of contacting the outer diameter surface of the roller, and this retaining portion extends parallel to the axis of the leg shaft and is arranged along the roller guide surface.

2. The tripod-type constant velocity universal joint according to claim 1, wherein the retaining portion of the clip contacts the outer diameter surface of the roller at the end in the torque transmission direction when the roller is viewed from the joint axis direction.

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