Ntn Corporation

Ntn Driveshaft, Inc.

Taku Itagaki

Tatsuro Sugiyama

Minoru Ishijima

Yuichi Asano

Tatsuhiro Goto

Hiroshi Kawamura

Hisaaki Kura

Masahiro Ozawa

Hiroshi Adachi

Tohru Nakagawa

Kiyoshige Yamauchi

Tomoshige Kobayashi

Shintaro Suzuki

Kisao Yamazaki

Yukihiro Watanabe

Jiahua Miao

Shunsuke Makino

Takeyoshi Konomoto

Hiroshi Murakami

Seiya Kato

Brian Drier

Shouta Kawata

Makoto Ikki

A tripod type constant velocity universal joint includes an outer joint member having three track grooves each including roller guide surfaces opposing each other in a circumferential direction of each of the track grooves, a tripod member including three leg shafts, and roller units each including a roller and an inner ring to support the roller. An outer peripheral surface of the roller has a partially spherical surface having a curvature center on an axis of each of the leg shafts. The roller guide surfaces are each formed of a partially cylindrical surface having a curvature center on a horizontal line passing an intersection of a pitch circle of the track grooves and a center line of each of the track grooves, and when no torque is applied to the joint, an end portion of the outer peripheral surface of the roller abuts against the roller guide surfaces.

Tripod type constant velocity universal joint

A tripod type constant velocity universal joint includes an outer joint member that includes track grooves, a tripod member that includes three leg shafts protruding in a radial direction, a roller that is inserted into the track groove, and an inner ring that is fitted onto the leg shaft, and rotatably supports the roller. A hardened layer is formed on a surface of each leg shaft by carburizing, hardening, and tempering. The tripod member is formed a steel material having a carbon content of 0.23% to 0.44%. An effective hardened layer depth of the hardened layer by using, as a Ts torque, 0.3 times a minimum static torsional torque at which a shaft coupled to the tripod member causes torsional fracture and 600HV as limit hardness is equal to or greater than a maximum shear stress depth Z when the Ts torque is applied.

Tripod-type constant velocity universal joint

A power transmission shaft includes a metal shaft member, and a resin shaft member connected to the metal shaft member in an axial direction of the power transmission shaft. The resin shaft member is made of fiber reinforced plastic. The metal shaft member and the resin shaft member are joined to each other through a close-contact fitting portion between a male spline, which is formed in an outer surface of the metal shaft member, and a female spline formed by press-fitting the male spline into the resin shaft member. An edge is formed at a radially outer edge portion of a press-fitting-start end surface of the male spline of the metal shaft member.

Power transmission shaft

A corrugated portion is formed in one end edge portion of the metallic shaft main body (), and a triangular corrugated portion () is formed in an end edge portion of the shaft auxiliary body () on the metallic shaft main body side. The metallic shaft main body () and the shaft auxiliary body () are integrated by being linearly arranged by way of meshing that brings a side of the triangular corrugated portion () on the main body side and a side of the triangular corrugated portion () on the auxiliary body side into contact with each other. A fiber orientation angle (&#x3b8;) of the fiber reinforced plastic of the shaft auxiliary body () is set so as to be in the same direction as a direction of stress generated in a hypotenuse of each triangular portion under a torque load state.

A tripod type constant velocity universal joint includes an outer joint member including three track grooves having roller-guide surfaces arranged to face each other in a circumferential direction, a tripod member including three leg shafts projecting in a radial direction, and roller units each including a roller and an inner ring for supporting the roller in a freely rotatable manner. The inner ring is externally fitted to a corresponding one of the three leg shafts. The roller is movable along the roller-guide surfaces of a corresponding one of the three track grooves. Each of the three leg shafts includes a region formed into a substantially circular-arc shape in horizontal cross-section that is orthogonal to an axial line of each of the three leg shafts.

Tripod type constant velocity universal joint and method for producing same

A constant velocity universal joint having a recess-projection engagement configuration in which backlash at a shaft connecting region does not easily occur, and an inner joint component and a shaft can he firmly connected. hi the constant velocity universal joint, the inner joint component and the shaft () fitted into an axis hole () of the inner joint component are connected by die recess-projection engagement configuration. Engagement contacting regions () of projections () and recesses () corresponding thereto are in close contact over the whole region.

Constant velocity universal joint

A heat treatment method is capable of molding, by mobile quenching of induction quenching, an outer joint member of a tripod type constant velocity universal joint having excellent strength without forming hardened layers in larger radially-inner portions. Mobile quenching is performed in such a manner that a high-frequency induction heating coil is moved in an axial direction relative to an outer joint member, and thus hardened layers are formed on the roller guide surfaces. Magnetic field line cut-out bodies for cutting out generated magnetic field lines are arranged on the high-frequency induction heating coil. The larger radially-inner portions become an unquenched portion by cutting out the magnetic field lines with the magnetic field line cut-out bodies.

Heat treatment method, outer joint member, and tripod type constant velocity universal joint

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.

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.

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Shizuoka, Japan

Taku Itagaki