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.

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.

The claimed invention is directed to a novel composite half shaft. More specifically, the claimed invention provides for the integration of a continuous velocity joint within the hollow tubular portion of the axle shaft, which permits for a longer lightweight composite hollow shaft. The use of the lightweight material over additional length results in an overall weight reduction. Additional benefits include reduced unsprung weight in vehicles, improved mileage for gas powered vehicles and increased range for electric vehicles. The use of composite materials in place of a solid or hollow metal axle bar results in improved noise, vibration and harshness (“NVH”) characteristics over conventional half shafts..

A rotational driving force transmission mechanism includes a cylindrical shaft made of fiber reinforced plastic, and a first constant velocity joint. The shaft is joined to the first constant velocity joint via a metallic intervening member which is attached to one end of the shaft in the axial direction. The intervening member includes a shaft portion and a main body portion. The shaft portion is inserted into the one end of the shaft from a distal end side thereof. The main body portion is of a bottomed tubular shape made up from a bottom part joined to a proximal end side of the shaft portion, and a tubular portion fitted over the one end of the shaft. The first constant velocity joint includes an inner ring fitted externally over the tubular portion of the intervening member.

An angle-adjustable tripod universal joint which has one tripod, three rollers and one universal joint outer part. An inner wall of the universal joint outer part has three roller tracks, and one roller is disposed in each of the roller tracks and rolls along the roller track. The inner cavity of each roller has a rotatably disposed spherical shaft head of the tripod. The inner wall of each roller track has a guiding groove. The peripheral shape of each roller is cylindrical. The bottom surface of the guiding groove is a plane surface, and two side surfaces of the guiding groove are flat surfaces perpendicular to the plane surface. The peripheral surface of each roller is partially inserted into the corresponding guiding groove, and the peripheral surface of the roller is tangent to the corresponding plane surface.

An angle-adjustable tripod universal joint which has one tripod, three rollers and one universal joint outer part. An inner wall of the universal joint outer part has three roller tracks, and one roller is disposed in each of the roller tracks and rolls along the roller track. The inner cavity of each roller has a rotatably disposed spherical shaft head of the tripod. The inner wall of each roller track has a guiding groove. The peripheral shape of each roller is cylindrical. The bottom surface of the guiding groove is a plane surface, and two side surfaces of the guiding groove are flat surfaces perpendicular to the plane surface. The peripheral surface of each roller is partially inserted into the corresponding guiding groove, and the peripheral surface of the roller is tangent to the corresponding plane surface.

An object is to provide a constant velocity universal joint boot that can improve resistance to fatigue failure and achieve further extension of service life even if a constant velocity universal joint swings at a large operating angle. To achieve this object, a constant velocity universal joint boot is adopted, in which a large-diameter annular portion mounted on a mating member whose outer circumferential surface is formed into a non-circular shape, and at least a part of the inner circumferential surface of the large-diameter annular portion formed into a non-circular shape, and the large-diameter annular portion, a boot bellows portion, and a small-diameter annular portion attached to a shaft are integrated, and an annular recess is provided in that part of the inner circumferential surface of the large-diameter annular portion which is adjacent to the bellows.

An object is to provide a constant velocity universal joint boot that can improve resistance to fatigue failure and achieve further extension of service life even if a constant velocity universal joint swings at a large operating angle. To achieve this object, a constant velocity universal joint boot is adopted, in which a large-diameter annular portion mounted on a mating member whose outer circumferential surface is formed into a non-circular shape, and at least a part of the inner circumferential surface of the large-diameter annular portion formed into a non-circular shape, and the large-diameter annular portion, a boot bellows portion, and a small-diameter annular portion attached to a shaft are integrated, and an annular recess is provided in that part of the inner circumferential surface of the large-diameter annular portion which is adjacent to the bellows.

An articulated shaft includes a hollow shaft and a joint formed by a first outer ring element and a first inner ring element in the interior of the first outer ring element which joint is configured to transmit a torque from the hollow shaft to an axle connected to the inner ring element. The outer ring element is formed one-piece with the hollow shaft and/or the inner ring element is formed one-piece with the axle.

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.