Ntn Corporation

Sumitomo Metal Industries, Inc.

Tatsuhiro Goto

Hisaaki Kura

Tatsuro Sugiyama

Kenji Terada

Kazuhiko Yoshida

Kenta Yamazaki

Shigeyoshi Ishiguro

Akio Sakaguchi

Akira Wakita

Kenji Aihara

Katsuhiro Suzuki

Taku Itagaki

Yasuhide Fujioka

Naohiro Une

Shintaro Suzuki

Yukihiro Watanabe

Hiroshi Tone

Toyofumi Hasegawa

Hideki Kondo

Hiroshi Murakami

Tatsurou Sugiyama

Masahide Miyata

Mikio Tomiyama

Hideo Takeshita

Toshio Kawasaki

Toshiki Suwa

Unpleasant vibration and muffled sound are restrained. A constant velocity universal joint includes an outer joint part having a plurality of track grooves formed on its cylindrical inner circumferential surface and extending in an axial direction, an inner joint part having a plurality of track grooves formed on its spherical outer circumferential surface and extending in the axial direction, six torque transmitting balls, each being put in a ball track formed by a pair of the track groove of the outer joint part and the track groove of the inner joint part, and a cage having pockets for retaining the torque transmitting balls. The center of curvatures of the spherical outer circumferential surface and the center of the spherical inner circumferential surface of the cage are offset by the same distance in the opposite directions along the axis about the center of the joint. A circumferential arrangement of the ball tracks is made with a uniform pitch, and the circumferential length of the pockets of the cage is made uneven at least at one location.

Plunging constant velocity universal joint

Unpleasant vibration and muffled sound are restrained. A constant velocity universal joint includes an outer joint part having a plurality of track grooves formed on its cylindrical inner circumferential surface and extending in an axial direction, an inner joint part having a plurality of track grooves formed on its spherical outer circumferential surface and extending in the axial direction, six torque transmitting balls, each being put in a ball track formed by a pair of the track groove of the outer joint part and the track groove of the inner joint part, and a cage having pockets for retaining the torque transmitting balls. The center of curvatures of the spherical outer circumferential surface and the center of the spherical inner circumferential surface of the cage are offset by the same distance in the opposite directions along the axis about the center of the joint. A circumferential arrangement of the ball tracks is made with a uniform pitch, and a circumferential arrangement of the pockets of the cage is made with a random and non-uniform pitch of 55&#xb0; or more.

The tripod member has three trunnions which are projected radially. Each of the trunnions carries a roller, and this roller is accommodated in one of the track grooves in the outer joint member. The outer peripheries of the rollers and the roller guideways make angular contact with each other. Support rings are fitted onto the outer peripheries of the trunnions. These support rings and the rollers are assembled (unitized) via a plurality of needle rollers to constitute roller assemblies capable of relative rotations. In longitudinal sections, the outer peripheries of the trunnions have straight shapes parallel to the axes of the trunnions. In cross sections, the outer peripheries are elliptic in shape, with their respective major axes perpendicular to the axis of the joint. The inner peripheries of the support rings have arcuate convex sections.

Constant velocity universal joint

A constant velocity universal joint includes an outer joint member has three track grooves extending axially in an inner circumference portion thereof with a roller guide surface extending axially on each side of the respective track grooves; a tripod member has three trunnions protruding in the radial direction; and a roller mechanism is mounted in each of the trunnions of the tripod member. The roller mechanism is capable of swinging and oscillating freely with respect to the trunnions, and has a roller guided along the roller guide surface in the direction parallel to the axis line of the outer joint member. An outer peripheral surface of the roller, which is made by ground-finishing, is in contact with the roller guide surface, and has a surface roughness of 0.35 Ra or less.

In a no-flange type outer joint member, the amount of abrasion in a large inner diameter portion formed for a track groove is intended to be restrained. In a tripod type constant velocity universal joint including: a no-flange type outer joint member; and a roller assembly including a roller, being attached to a trunnion so as to be capable of oscillating, hardened layers are formed on portions of a large inner diameter portion of the outer joint member, which are in contact with an inclined roller assembly. In this case, a value of F/D is set equal to or less than 0.45, where a distance from a center of the track groove of the outer joint member to the ends of both the hardened layers on the side of the center of the track groove is F, and a diameter of an outer circumference of the roller assembly is D.

An annular support ringis fitted onto the outer periphery of each trunnion. This support ringand the rollerare unitized via a plurality of needle rollersto constitute a roller assembly capable of relative rotations therebetween. In longitudinal section, each trunnionhas an outer periphery of straight shape, parallel to the axis of the trunnion. In cross section, the trunnionhas a generally ellipse shape with the major axis orthogonal to the axis of the joint. The inner periphery of each support ringis arcuate and convex in section. This combines with the general elliptic cross sections of the trunnionsand the provision of predetermined clearances between the trunnionsand the support rings, to allow the support ringsto move along the axial directions of the trunnionsas well as make tilting movements with respect to the trunnions

A constant velocity universal joint is disclosed which includes an outer joint member with three axial track grooves and a tripod member with three radially projecting trunnion journals, each of the trunnion journals carrying a roller assembly received in each of the track grooves, a projection being formed at an end of each trunnion for interference with the roller assembly.

Constant velocity joint

An annular support ring is fitted onto the outer periphery of each trunnion . This support ring and the roller are unitized via a plurality of needle rollers to constitute a roller assembly capable of relative rotations therebetween. In longitudinal section, each trunnion has an outer periphery of straight shape, parallel to the axis of the trunnion . In cross section, the trunnion has a generally ellipse shape with the major axis orthogonal to the axis of the joint. The inner periphery of each support ring is arcuate and convex in section. This combines with the general elliptic cross sections of the trunnions and the provision of predetermined clearances between the trunnions and the support rings , to allow the support rings to move along the axial directions of the trunnions as well as make tilting movements with respect to the trunnions

A constant velocity universal joint has a ring that is fitted on each trunnion and rotatably supports a corresponding roller so the roller is movable axially of an outer joint member along a roller guide surface. The outer circumferential surface of each trunnion has a straight shape, as viewed in the longitudinal section, and has, as viewed in the cross section, a shape which allows contact with the inner circumferential surface of the ring in a direction orthogonal to the axis of the outer joint member. A generatrix of the inner circumferential surface of the ring forms part of an ellipse having a major axis extending in a direction orthogonal to the axis of the ring or is composed of a central convex circular arc and a tangential line extending from an end portion of the circular arc to an end face of the ring.

Growing community of inventors

Shizuoka-ken, Japan

Tatsuhiro Goto