In a lateral cross section passing through a center of a trunnion in the form of a retaining member that constitutes part of a constant velocity joint, and an orthogonal site where a virtual tangent line at a contact region is perpendicular to a longitudinal direction of a guide groove, a curved surface having a first arcuate portion and a second arcuate portion is formed. The second arcuate portion is contiguous with the first arcuate portion, and has a smaller radius of curvature than the first arcuate portion. Further, the first arcuate portion and the second arcuate portion are arranged in this order from a side in proximity to an annular member of the trunnion.

A constant velocity joint includes spherical rollers. At least parts of first inner bottom wall portions provided on an inner bottom wall surface of a cylindrical portion of the constant velocity joint are located in closer proximity to the side of an opening of the cylindrical portion than second inner bottom wall portions. When the spherical rollers are disposed at an innermost location inside the cylindrical portion and the axial directions of the spherical rollers are perpendicular to the axial direction of the cylindrical portion, at least parts of the first inner bottom wall portions abut against inner side outer circumferential surface portions of the spherical rollers, and the second inner bottom wall portions are separated away from outer side outer circumferential surface portions of the spherical rollers.

Provided is a tripod type constant velocity universal joint (1), including: an outer joint member (2) having track grooves (6) formed at trisected positions in a circumferential direction to extend in an axial direction; a tripod member (3) including leg shafts (9) radially projecting from trisected positions in the circumferential direction; and rollers (4) fitted in a freely rotatable manner about the leg shafts (9), respectively, and received in the track grooves (6), respectively, in which a radially outer surface (4a) of each of the rollers (4) is formed of a surface unsubjected to grinding or cutting work after heat treatment.

The wide-angle constant velocity joint (100) includes: a central core (101) forming respective inner yokes (24, 25) for connection and in which there is housed a guide disc (11); and outer yokes (103, 105). The central core (101) forms a lubricant reservoir (1) in communication with an annular seat (7) in which the guide disc (11) is slidingly received.

A joint for the angularly adjustable drive-connection of a cylinder block and a driveshaft of a hydrostatic bent axis piston unit. The joint has a shank which is rotatable about its longitudinal axis defining a joint axis, on both ends of the shank roller carriers project radially and basically perpendicular to the joint axis. On each roller carrier a roller is provided rotatable around a roller axis. The rollers are secured in axial direction against slipping-off of the roller carriers by means of an embossed area located axially outside of the roller on the respective distal end portion of the roller carrier.

A joint for the angularly adjustable drive-connection of a cylinder block and a driveshaft of a hydrostatic bent axis piston unit. The joint has a shank which is rotatable about its longitudinal axis defining a joint axis, on both ends of the shank roller carriers project radially and basically perpendicular to the joint axis. On each roller carrier a roller is provided rotatable around a roller axis. The rollers are secured in axial direction against slipping-off of the roller carriers by means of an embossed area located axially outside of the roller on the respective distal end portion of the roller carrier.

A tripod type constant velocity universal joint includes an outer joint member having track grooves, a tripod member including trunnion journals, and spherical rollers each fitted in a rotatable manner about each of the trunnion journals through intermediation of a plurality of needle rollers. A corner portion is formed at a root portion of each of the trunnion journals so as to restrict movement of the plurality of needle rollers in the axial direction toward the root portion of each of the trunnion journals by interference between an end surface corner rounded portion of each of the plurality of needle rollers and the corner portion at the root portion.

A constant velocity universal joint includes an outer joint member having an opening portion at one end thereof, and an inner joint member configured to transmit torque while allowing angular displacement with respect to the outer joint member through balls. End portions of a boot closing the opening portion of the outer joint member are fastened and fixed to a mounting part of the outer joint member and a mounting part of a shaft extending from the inner joint member. At a part of an outer peripheral surface of the shaft where at least an inner peripheral surface of the boot contacts when the shaft takes an operating angle with respect to the outer joint member, a sliding bearing is arranged to reduce abrasion due to friction caused by relative movement between the outer peripheral surface of the shaft and the inner peripheral surface of the boot.

A tripod constant-velocity joint includes: an outer joint member having a cavity elongated in a longitudinal direction and three roller tracks; an inner joint member having a center body and three journals outwardly radially protruded from the center body; and three roller assemblies respectively coupled to the journal in a state of being respectively disposed in the roller tracks. The respective roller assembly comprises: an inner race which is connected to the journal and is provided with a first inner ball groove and a second inner ball groove on both lateral sides thereof; a first ball array and a second ball array respectively having a plurality of balls which are respectively disposed in the first inner ball groove and in the second inner ball groove; and a ball cage which restricts movements of the first ball array and the second ball array in a longitudinal direction thereof.

A first constant velocity joint is equipped with a cup part made of a light alloy. First ball grooves that receive a torque from torque transmitting members are formed on an inner wall of the cup part. A high hardness layer made of ceramic or cermet as a principal component thereof is formed on an inner surface of the cup part including at least inner surfaces of the first ball grooves.