Abstract: A fixed type constant velocity joint includes an outer ring (1), an inner ring (2), torque transmitting balls (3), a cage (4), and a pre loading mechanism in which either a pressing section for axially applying an elastic pressing force or a receiving section for receiving the pressing force from the pressing section is disposed in the cage (4), the other being disposed in the inner ring (2). The axial clearance between the inner ring (2) and the cage (4) is greater than the axial clearance which is due to the radial clearance of the track, and the axial clearance which is produced by the radial clearance of the track is 2.5-6.5 times as large as the radial clearance of the track. Further, the center of the outer spherical surface (2b) of the inner ring (2) is shifted to the spread side of the ball tracks (1a, 2a) over the center of the inner spherical surface (4b) of the cage, thereby improving the cross operation.

Abstract: A tripod type constant velocity joint including a hollow cylindrical housing fixed to the end of a first rotary shaft and formed with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, and roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing.

Abstract: The invention provides a grease composition for constant velocity joints and constant velocity joints in which the grease composition is packed. The composition comprises (a) a base oil comprising a synthetic oil; (b) a thickening agent; (c) a molybdenum sulfurized dialkyl dithiocarbamate; (d) a thiophosphate; and (e) a zinc sulfurized dialkyl dithiocarbamate. The composition can reduce low temperature rotational torque and folding torque in constant velocity joints while inhibiting deterioration of a boot material comprising a silicone rubber.

Abstract: To prevent inverting of a mountain portion (111) of a bellows member (11) when a rotating shaft (23) is angularly displaced, the boot comprising the bellows member (11) with large and small diameter mounting members (12, 13) is structured such that a first mountain portion (111) nearest the large diameter mounting member (12) raises from the large diameter mounting member (12), a length (L1) between a top (111a) of the first mountain portion (111) and a bottom (111b) at the large diameter mounting member (12) side is not more than a length (L2) between the inner peripheral position of the bottom (111b) and an end portion (21b) of an outer ring (21) at the rotating shaft (23) side, and a first valley portion (112) adjacent to the first mountain portion (111) is positioned at the rotating shaft (23) side from the end part (21b).

Abstract: A constant velocity universal joint shaft, capable of suppressing a rotational backlash when incorporated in the constant velocity universal joint, and improving the assembly efficiency as well as reducing the manufacturing cost. A constant velocity universal joint shaft has a spline that fits an inner race of the constant velocity universal joint. The shaft includes a shaft body with a spline formed thereon, and a yoke portion with a ring-shaped fitting portion. The shaft body and the yoke portion are integrally formed of medium carbon steel. By a pressing force of a pressing member the fitting portion of the yoke portion is tightened, so that such fitting portion fits a shaft external to the joint. In the constant velocity universal joint, the pressing member and an abutment member are elastically butted via an elastic member, so that a ball constantly remains in contact with a raceway of an outer member and a raceway of an inner member.

Abstract: To make a bellows section (1) of a boot to be flexibly and repeatedly deformable without deterioration in durability, to thereby reduce rotational resistance when a joint angle is large, the boot has the bellows portion (1) where three or more circumferentially extending crest portions (111-113) and root portions (121-122) therebetween are alternately formed; a large-diameter attaching portion (2) formed at one end of the bellows portion; and a small-diameter attaching portion (3) formed at the other end, a rising wall (1a) closest to the large-diameter attaching portion (2) and a rising wall (1f) closest to the small-diameter attaching portion (3) have smaller wall thickness than other portions of the bellows section (1), and the ratio (t1/t2) of the thickness (t1) of the rising walls (1a, 1f) to the thickness (t2) of the other portions of the bellows portion (1) is set to 0.6?t1/t2<1.0.

Abstract: The pocket 4a of the retainer 4 comprises a pair of axial walls 4a1 opposed in the axial direction of the retainer 4, a pair of circumferential walls 4a2 opposed in the circumferential direction, and corner round sections 4a3 connecting the axial wall 4a1 and the circumferential wall 4a2. The ratio (R/d) of the radius of curvature R of the corner round section 4a3 to the diameter d of the torque transmission ball 3 is set in a range of 0.45?R/d?0.62. Also, the circumferential wall 4a2 and the corner round sections 4a3 are drawn in a single arc with the radius of curvature R. Furthermore, as to the axial walls 4a1, grinding, cutting by quenched steel, or the like is carried out after the heat treatment (carburizing and quenching) of the retainer 4 in order to reduce variations in a processing margin.

Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher

Abstract: A fixed type constant velocity joint comprising an outer ring (1), an inner ring (2), torque transmitting balls (3), a cage (4), and a preloading mechanism in which either a pressing section for axially applying an elastic pressing force or a receiving section for receiving the pressing force from the pressing section is disposed in the cage (4), the other being disposed in the inner ring (2). The axial clearance between the inner ring (2) and the cage (4) is greater than the axial clearance which is due to the radial clearance of the track, and the axial clearance which is produced by the radial clearance of the track is 2.5-6.5 times as large as the radial clearance of the track. Further, the center of the outer spherical surface (2b) of the inner ring (2) is shifted to the spread side of the ball tracks (1a, 2a) over the center of the inner spherical surface (4b) of the cage, thereby improving the cross operation.

Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher

Abstract: 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.

Abstract: It is arranged that in a fixed type constant velocity joint 1 having a plurality of torque transmitting ball tacks 30, the torsional angle at the input torque 0 Nm in a torque-torsional angle diagram be approximately 0. Further, the torsional rigidity in the vicinity of input torque 0 Nm in the torque-torsional angle diagram is placed in a range of 1.5 Nm/deg to 6 Nm/deg.

Abstract: 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.

Abstract: The present invention aims to achieve the high rigidity and light weight of a connecting shaft of a constant velocity universal joint, and to reduce manufacturing costs. A hollow connecting shaft 5 is provided with an axial end section 5c having teeth 5c which are engaged with an engagement section 2d of an inner member 2, and a middle section 5d continued from the axial end section 5c. To mold the connecting shaft 5, both end sections of a pipe material with an outside diameter dm are drawn, and then the teeth (splines or serrations) 5c are molded in the outer periphery of the drawing-molded axial end section 5c on an axial end side by form rolling or the like. The outside diameter of the axial end section 5c is ds, and the outside diameter of the middle section 5d is dm as with that of the pipe material (ds<dm).

Abstract: The present invention provides a fixed type constant velocity universal joint suitable for applications where vibration is harmful. A fixed-type constant velocity universal joint (1) includes an inner member (20) fitted in an outer member (10) with a retainer (40) therebetween, and balls (30) provided between track grooves (14, 24) of the outer member (10) and the inner member (20) as well as retained by the retainer (40). The outer member (10) is constructed as a multilayer structure of three or more layers formed of an outside member (15), one or a plurality of intermediate members (16), and an inside member (17), and at least one of the intermediate members (16) is constructed of an elastic material. Cushioning action of the intermediate members (16) can reliably absorb vibration transmitted from either of the outer member (10) and the inner members (20) with the members (10, 20) set to a predetermined operation angle.

Abstract: 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.

Abstract: A fixed constant velocity joint is provided, which is suitable for an application where a rotational backlash should be avoided. A pressing member is attached to a shaft, and simultaneously a receiving member is attached to a cage. Then, an elastic force of an elastic member elastically bring a pressing part of the pressing member in contact with a receiving part of the receiving member. As a result, an inner race and a cage relatively travel in the axial direction, balls are pushed toward a direction along which wedge-shape ball tracks narrow, and consequently a track clearance in the axial direction decreases.

Abstract: A constant velocity universal joint shaft, capable of suppressing a rotational backlash when incorporated in the constant velocity universal joint, and improving the assembly efficiency as well as reducing the manufacturing cost, is to be provided. The present invention relates to the constant velocity universal joint shaft having a spline that fits an inner race of the constant velocity universal joint. The shaft includes a shaft body with a spline formed thereon, and a yoke portion with a ring-shaped fitting portion. The shaft body and the yoke portion are integrally formed of medium carbon steel. By a pressing force of a pressing member the fitting portion of the yoke portion is tightened, so that such fitting portion fits a shaft external to the joint. In the constant velocity universal joint, the pressing member and an abutment member are elastically butted via an elastic member, so that a ball constantly remains in contact with a raceway of an outer member and a raceway of an inner member.

Abstract: 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.

Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher