JP2008075683A - Tripod type constant velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a roller assembly from dropping from a trunnion journal of a single roller type tripod type constant velocity universal joint. <P>SOLUTION: The tripod type constant velocity universal joint is provided with: an outer joint member including a track groove extending in a shaft direction in a position circumferentially divided into three equal parts of an inner circumference; a tripod member 20 including the spherical trunnion journal 26 projecting in a radius direction from the position circumferentially divided into three equal parts; and the roller assembly 30 rotatably supported by the respective trunnion journals 26. The roller assembly 30 is provided with: a roller 32; a plurality of rollers 44 arranged between the roller 32 and the trunnion journal 26; and a means 40 for preventing the roller assembly 30 from dropping from the trunnion journal 26. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sliding tripod type constant velocity universal joint, and can be used for power transmission devices such as automobiles and various industrial machines.

  Tripod type constant velocity universal joint Tripod type constant velocity type in which the outer roller rolls in parallel with the track groove of the outer joint member in order to prevent vehicle shudder caused by the tertiary induced thrust of rotation. There is a universal joint (Patent Documents 1 and 2). It is known that maintaining the rolling direction of the roller in a straight line with respect to the track groove in this manner has a certain effect in reducing the rolling resistance of the roller and reducing the third-order induced thrust.

Patent Document 3 describes a single roller type tripod type constant velocity universal joint with a simple structure (see FIG. 5). In this type, the inclination of the trunnion journal is absorbed between the roller and the trunnion journal, so that the roller can roll parallel to the track groove, the induced thrust is reduced, and the vehicle shudder phenomenon is reduced.
JP 2000-320563 A JP 2001-132766 A Japanese Patent Laid-Open No. 10-184715

  There is a functional clearance between the trunnion journals. In the assembly process, the outer joint member is covered immediately after the roller assembly is set on the trunnion journal. Functionally, it is not necessary to prevent the trunnion journal and the roller assembly from coming off, but since the roller assembly must be held until the outer joint member is completely covered, its management is not easy. Conversely, if the tripod member and the roller assembly can be assembled and integrated (made into a kit), the assembly process to the outer joint member can be simplified.

  In addition, when the user removes the drive shaft from the vehicle, the user may think that the roller assembly or tripod member falls off the outer joint member beyond the allowable slide range. Also in this case, if there is no retaining between the trunnion journal and the roller assembly, the roller assembly falls off the trunnion journal.

  An object of the present invention is to prevent a roller assembly from falling off a trunnion journal in a single roller type tripod type constant velocity universal joint.

  The tripod type constant velocity universal joint of the present invention is a single roller type tripod type constant velocity universal joint that solves the problem by providing the roller assembly itself with means for preventing the roller assembly from falling off the trunnion journal. That is, the tripod type constant velocity universal joint according to claim 1 has an outer joint member in which a track extending in the axial direction is formed at a circumferentially divided position of three in the inner circumference, and a radially protruding portion from the circumferentially divided position of three. A tripod member having a spherical trunnion journal and a roller assembly rotatably supported on each trunnion journal, the roller assembly comprising a roller and a plurality of rollers arranged between the roller and the trunnion journal; And means for preventing the roller assembly from falling off the trunnion journal.

  According to a second aspect of the present invention, in the tripod type constant velocity universal joint according to the first aspect of the present invention, the tripod type constant velocity universal joint includes a pair of flange portions that guide the rollers so as to roll in the circumferential direction of the rollers, Of these, the inner diameter of the tripod member located on the radially outer side is smaller than the maximum diameter of the trunnion journal.

  The invention according to claim 3 is the tripod type constant velocity universal joint according to claim 1 or 2, wherein the trunnion journal is positioned on both sides in the axial direction and forms a part of a true sphere. And a second curved surface having a radius of curvature larger than that of the first curved surface.

  According to a fourth aspect of the present invention, in the tripod type constant velocity universal joint according to any one of the first to third aspects, at least one of the pair of flanges is a retaining ring fixed to an inner diameter surface of the roller, The ring and the collar part and the both ends of the roller are engaged with each other in an uneven manner.

  The invention according to claim 5 is the tripod type constant velocity universal joint according to claim 4, characterized in that a convex portion is provided at both ends of the roller and is engaged with a concave portion formed in the retaining ring and the flange portion.

  The invention according to claim 6 is the tripod type constant velocity universal joint according to claim 5, wherein the concave portion is formed over the entire circumference of the retaining ring and the flange portion.

  According to the present invention, in the single-roller type sliding tripod type constant velocity universal joint, it is possible to prevent the roller assembly from dropping from the trunnion journal by providing the roller with the retaining stopper.

  Embodiments of the present invention will be described below with reference to the drawings.

  As shown in FIGS. 1 and 2, the tripod type constant velocity universal joint includes an outer joint member 10, a tripod member 20, and a roller assembly 30.

  The outer joint member 10 includes a mouth portion 12 and a stem portion 16, and is coupled to one of the two shafts to be connected by the stem portion 16 so that torque can be transmitted by spline or serration. The mouse portion 12 has a cup shape opened at one end, and a track groove 14 extending in the axial direction is formed at a position equally divided into three in the circumferential direction of the inner periphery. The side walls of the track grooves 14 facing each other serve as roller guide surfaces.

  The tripod member 20 includes a boss portion 22 and a trunnion journal 26, and is coupled to the other of the two shafts to be connected by a spline (or serration) hole 24 formed in the boss portion 22 so that torque can be transmitted. The trunnion journal 26 protrudes in the radial direction from the circumferentially divided position of the boss portion 22. The outer peripheral surface 28 of each trunnion journal 26 has a spherical shape. The outer peripheral surface may be a perfect sphere, or, as shown in FIG. 5, the trunnion journal 26 is composed of a portion 28a located at both ends in the axial direction and a portion 28b located in the middle thereof, and the curvature of the latter from the former radius of curvature R1. The radius R2 may be large.

  The roller assembly 30 is rotatably supported on the trunnion journal 26. Each roller assembly 30 includes a roller 32, a plurality of rollers 36, and a retaining ring 48 attached to the roller 32. The roller 32 has a spherical outer peripheral surface 34 and a cylindrical inner peripheral surface 36, and the inner peripheral surface 36 becomes a raceway surface of the roller 36. The roller 36 has a cylindrical shape and is arranged so as to be able to roll between the roller 32 and the trunnion journal 26, and constitutes a so-called full roller bearing without a cage.

  As shown in FIGS. 3 and 4, a retaining ring groove 38 is formed at one end of the roller 32 in the axial direction, and a retaining ring 38 is attached thereto. The retaining ring 38 is formed by pressing a thin steel plate into a disk shape, and a circumferential groove 50 having a U-shaped cross section is formed over the entire circumference. Although not shown in the drawing, the retaining ring 38 is a so-called C-shaped retaining ring which is divided by slitting at one place in the circumferential direction, and is attached to the retaining ring groove 38 using elastic deformation. Yes.

  A flange 40 is formed at the other end of the roller 32 in the axial direction. The roller 44 is held from both sides in the axial direction by the flange portion 40 and the above-described retaining ring 48 and is guided so as to roll in the circumferential direction of the roller 32. Further, the roller 44 and the collar 40 and the roller 44 and the retaining ring 48 are engaged with each other. That is, in this embodiment, the recess 40 has a recess or circumferential groove 42 formed on the entire circumference, and the retaining ring 48 has a recess or circumferential groove 50 formed on the entire circumference. Further, by allowing the circumferential groove 42 of the collar 40 and the circumferential groove 50 of the retaining ring 48 to receive the convex portion 46 on the end face of the roller 44, the roller 44 is prevented from falling off the roller assembly 30. As a result, the roller assembly 30 can be unit-handled. In addition, instead of the circumferential grooves 42 and 50 over the entire circumference, independent concave portions having a predetermined pitch may be used.

  As a means for preventing the roller assembly 30 from falling off the trunnion journal 26, the inner diameter of the flange 40 or the retaining ring 48 that is located on the radially outer side of the tripod member 20 is made smaller than the maximum diameter of the trunnion journal 26. In the embodiment of FIG. 3, since the collar portion 40 is located on the inner side and the retaining ring 48 is located on the outer side, the inner diameter φd of the collar portion 40 is made smaller than the maximum diameter φD of the trunnion journal 26 (φd < φD).

  In the above-described embodiment, the inner diameter φd of the collar portion 40 is made smaller than the maximum diameter φD of the trunnion journal 26 and interference is provided, and as shown in FIG. A convex portion 40 a may be provided on the inner diameter side of the flange portion 40 of the roller 32. The convex portion 40a may be continuous over the entire circumference of the roller 32, or one or a plurality of independent convex portions may be provided. The convex portion 40a can be provided by mechanical removal processing (cutting / grinding) or plastic processing (caulking). The relationship between the inner diameter φd of the convex portion 40a and the maximum diameter φD of the trunnion journal 26 is φd <φD.

  In any case, when the roller assembly 30 is assembled to the trunnion journal 26, the inner diameter of the flange 40 or the protrusion 40a is overcome by using elastic deformation. If the interference (φD−φd) is exemplified, about 0.05 to 0.10 mm is desirable.

  Although not shown in the drawings, flanges may be formed at both ends of the roller 32, and the inner diameter of one of the flanges may be smaller than the maximum diameter of the trunnion journal 26. The illustrated embodiment is an example in which one of the collars at both ends of the roller is formed by a retaining ring 48 separate from the roller 32.

Partially broken front view of tripod member of tripod type constant velocity universal joint Vertical section of tripod type constant velocity universal joint Partial enlarged view of FIG. 1 showing the embodiment FIG. 1 is a partially enlarged view showing another embodiment. Partially cutaway front view similar to FIG. 1 showing another embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Outer joint member 12 Mouse | mouth part 14 Track groove 16 Stem part 20 Tripod member 22 Boss part 24 Spline hole 26 Trunnion journal 28 Outer peripheral surface 28a Both ends (curvature radius R1)
28b Middle part (curvature radius R2)
30 Roller assembly 32 Roller 34 Outer peripheral surface 36 Inner peripheral surface (track surface)
38 retaining ring groove 40 collar 40a protrusion 42 circumferential groove (concave)
44 Roller 46 Convex part 48 Retaining ring 50 Circumferential groove (concave part)

Claims (6)

  An outer joint member in which a track extending in the axial direction is formed at an inner circumferential circumferential three-divided position, a tripod member having a spherical trunnion journal projecting radially from the circumferential three-divided position, and each trunnion journal A roller assembly rotatably supported by the roller assembly, the roller assembly comprising a roller, a plurality of rollers arranged between the roller and the trunnion journal, and means for preventing the roller assembly from falling off the trunnion journal. Type constant velocity universal joint.   The roller has a pair of flanges that guide the rollers so as to roll in the circumferential direction of the rollers, and the inner diameter of the flange located on the radially outer side of the tripod member is the trunnion journal. The tripod type constant velocity universal joint of Claim 1 smaller than a maximum diameter.   The trunnion journal includes a first curved surface that forms part of a true sphere located on both sides in the axial direction, and a second curved surface that is located between the first curved surface and has a larger radius of curvature than the first curved surface. The tripod type constant velocity universal joint of Claim 1 or 2 which has a curved surface.   The at least one of the pair of flange portions is a retaining ring fixed to the inner diameter surface of the roller, and the retaining ring and the flange portion and both ends of the roller are engaged with each other in an uneven manner, respectively. Any tripod type constant velocity universal joint.   The tripod type constant velocity universal joint according to claim 4, wherein convex portions are provided at both ends of the roller and engaged with the concave portions formed in the retaining ring and the flange portion. 6. The tripod constant velocity universal joint according to claim 5, wherein the recess is formed over the entire circumference of the retaining ring and the flange.

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