Abstract: A tripod constant-velocity joint including: an inner ring; three trunnions protruding from the inner ring; three roller units supported by the trunnions; and an outer ring storing the roller units. Each roller unit includes: an inner roller that is in contact with a convex outer-circumferential surface of the corresponding trunnion at a tangent point; an outer roller supported by the inner roller through rolling elements that are interposed between the inner and outer rollers; and a limiting portion protruding from the outer roller, so as to limit movements of the rolling elements and the inner roller. A clearance between the inner roller and the limiting portion is smaller than an axial length of a crowned end portion of each rolling element, and is larger than a stroke distance of reciprocating movement of the tangent point when a joint angle of the tripod constant-velocity joint is a predetermined value.

Abstract: A tripod constant-velocity joint including: an inner ring; three trunnions protruding from the inner ring; three roller units supported by the trunnions; and an outer ring storing the roller units. Each roller unit includes: an inner roller that is in contact with a convex outer-circumferential surface of the corresponding trunnion at a tangent point; an outer roller supported by the inner roller through rolling elements that are interposed between the inner and outer rollers; and a limiting portion protruding from the outer roller, so as to limit movements of the rolling elements and the inner roller. A clearance between the inner roller and the limiting portion is smaller than an axial length of a crowned end portion of each rolling element, and is larger than a stroke distance of reciprocating movement of the tangent point when a joint angle of the tripod constant-velocity joint is a predetermined value.

Abstract: A tripod constant-velocity joint including: an inner ring; three trunnions protruding from the inner ring; three roller units supported by the trunnions; and an outer ring storing the roller units. Each roller unit includes: an inner roller that is in contact with a convex outer-circumferential surface of the corresponding trunnion at a tangent point; an outer roller supported by the inner roller through rolling elements that are interposed between the inner and outer rollers; and a limiting portion protruding from the outer roller, so as to limit movements of the rolling elements and the inner roller. A clearance between the inner roller and the limiting portion is smaller than an axial length of a crowned end portion of each rolling element, and is larger than a stroke distance of reciprocating movement of the tangent point when a joint angle of the tripod constant-velocity joint is a predetermined value.

Abstract: A constant velocity joint includes: an outer joint member having a raceway groove; an inner joint member having a leg shaft; a roller that is able to roll on the raceway groove; and a needle bearing that supports an inner periphery of the roller such that the inner periphery of the roller is able to rotate with respect to the leg shaft. The leg shaft includes: a roll portion that supports the needle bearing; a contact portion that is able to contact an end face of the needle bearing, the end face facing a first side in the direction of a central axis of the needle bearing; and a recess portion formed between the roll portion and the contact portion, in a position where the recess portion is recessed from a space in which the needle bearing is disposed.

Abstract: In a constant-velocity joint, a center locus of a ball rolling on a first outer large-diameter portion has an arc shape having an arc center, and a center locus of the ball rolling on a second outer large-diameter portion has an arc shape having an arc center. Center loci of the ball rolling on an outer extension portion are positioned, throughout their lengths, in a region inducing a tangent line to an opening-side end portion of the center locus of the ball rolling on the second outer large-diameter portion, the region being positioned outward of the tangent line in a radial direction of the outer joint member. An opening-side end portion of the center locus of the ball rolling on the outer extension portion is positioned outward of the tangent line in the radial direction of the outer joint member.

Abstract: A constant-velocity joint 1 includes an outer ring with three raceway grooves formed therein, a tripod member having three tripod shaft portions, and roller units each having a cylindrical inner roller externally fitted over the corresponding tripod shaft portion and an outer roller. The outer roller has an annular surface facing a ceiling surface of a raceway groove. The ceiling surface includes first and second contact portions and that come into contact with an outer edge of the annular surface when the roller unit is tilted. When an outside diameter of the annular surface is represented as a roller end surface diameter A, a width of the outer roller in an axial direction is represented as a roller width B, and an interval between the first and second contact portions is represented as a contact portion interval H, a relational expression (A+B)/H?2.5 is satisfied.

Abstract: In a constant-velocity joint, a center locus of a ball rolling on a first outer large-diameter portion has an arc shape having an arc center, and a center locus of the ball rolling on a second outer large-diameter portion has an arc shape having an arc center. Center loci of the ball rolling on an outer extension portion are positioned; throughout their lengths, in a region inducing a tangent line to an opening-side end portion of the center locus of the ball rolling on the second outer large-diameter portion, the region being positioned outward of the tangent line in a radial direction of the outer joint member. An opening-side end portion of the center locus of the ball rolling on the outer extension portion is positioned outward of the tangent line in the radial direction of the outer joint member.

Abstract: A constant velocity joint includes: an outer joint member having a raceway groove; an inner joint member having a leg shaft; a roller that is able to roll on the raceway groove; and a needle bearing that supports an inner periphery of the roller such that the inner periphery of the roller is able to rotate with respect to the leg shaft. The leg shaft includes: a roll portion that supports the needle bearing; a contact portion that is able to contact an end face of the needle bearing, the end face facing a first side in the direction of a central axis of the needle bearing; and a recess portion formed between the roll portion and the contact portion, in a position where the recess portion is recessed from a space in which the needle bearing is disposed.

Abstract: A sliding constant velocity joint 1 includes: an outer ring serving as an outer member; a tripod member serving as an inner member; an intermediate member that is formed by a pair of divided members placed so as to be separated from each other with a head of a tripod shaft portion interposed therebetween; a plurality of rolling elements that roll on first and second raceway surfaces of the outer ring; and a cage holding the plurality of rolling elements. When the rolling elements are pressed by the pair of divided members and the bodies of the rolling elements are brought into contact with the pair of raceway surfaces, there is predetermined clearance between an outer peripheral surface of a needle-like projection of each rolling element and outer side surfaces in first and second grooves.

Abstract: A sliding constant-velocity joint includes: an outer ring, in the inner surface of which a plurality of raceway grooves are formed; a tripod member that transfers torque between the outer ring and a shaft; an intermediate member that swingably supports a tripod shaft portion of the tripod member; a plurality of rolling elements that can roll along the outer surface of the intermediate member; and a cage that holds the rolling elements. The amount of movement of the intermediate member in a radial direction of the outer ring is restrained such that the intermediate member does not contact a neck portion of the tripod shaft portion or a boss portion because of tilt motion of the intermediate member caused along with swing motion of the tripod shaft portion during rotation of the outer ring and the shaft.

Abstract: A constant-velocity joint 1 includes an outer ring with three raceway grooves formed therein, a tripod member having three tripod shaft portions, and roller units each having a cylindrical inner roller externally fitted over the corresponding tripod shaft portion and an outer roller. The outer roller has an annular surface facing a ceiling surface of a raceway groove. The ceiling surface includes first and second contact portions and that come into contact with an outer edge of the annular surface when the roller unit is tilted. When an outside diameter of the annular surface is represented as a roller end surface diameter A, a width of the outer roller in an axial direction is represented as a roller width B, and an interval between the first and second contact portions is represented as a contact portion interval H, a relational expression (A+B)/H?2.5 is satisfied.

Abstract: A tripod constant velocity joint includes, an outer race, a tripod, an inside member, a plurality of rolling elements, and a holding member. The inside member includes a fitted part having a non-cylindrical outer peripheral surface, the holding member includes a fitting part that has a non-cylindrical inner peripheral surface and is fitted to the fitted part, and the holding member is unable to rotate relative to the inside member as the fitted part and the fitting part are fitted to each other.

Abstract: One end face of an outer roller is provided with an annular rib that protrudes radially inward and that retains an inner roller and rolling elements. The other end face-side portion of the outer roller is provided with an inner component retaining portion that retains the inner roller and the rolling elements. In a roller unit in which the inner roller and the rolling elements are retained in the outer roller by the rib and the inner component retaining portion, an inner peripheral face of the inner roller through which a tripod shaft portion is passed is provided with a tripod shaft portion insertion restricting portion that allows the tripod shaft portion to be passed through the inner roller only from an end face side of the roller unit, on which the rib of the outer roller is not provided.

Abstract: One end face of an outer roller is provided with an annular rib that protrudes radially inward and that retains an inner roller and rolling elements. The other end face-side portion of the outer roller is provided with an inner component retaining portion that retains the inner roller and the rolling elements. In a roller unit in which the inner roller and the rolling elements are retained in the outer roller by the rib and the inner component retaining portion, an inner peripheral face of the inner roller through which a tripod shaft portion is passed is provided with a tripod shaft portion insertion restricting portion that allows the tripod shaft portion to be passed through the inner roller only from an end face side of the roller unit, on which the rib of the outer roller is not provided.

Abstract: A vehicle drive shaft includes: a first shaft portion, having a core shaft portion and a sleeve shaft portion coaxially arranged at one end, and a second shaft portion, having a spline hole portion and a second engagement protrusion at one end. A spline shaft portion and a first engagement protrusion are provided at distal ends of the core shaft portion and sleeve shaft portion. The spline hole portion is nonrotatably fixed to the spline shaft portion. The second engagement portion contacts the first engagement portion when a relative torsion allowable angle therebetween is larger than or equal to a gap. When the relative torsion allowable angle is smaller than the gap, torque is transmitted via the core shaft portion. When the relative torsion allowable angle is larger than or equal to the gap, torque is transmitted via not only the core shaft portion but also the sleeve shaft portion.