A tripod roller for a constant velocity universal joint includes inner and outer rings separated by a set of rollers. During assembly of the tripod roller the rollers are assembled to one of the inner and outer rings and then the other of the inner and outer rings is moved axially into position. Then, a forming tool is applied to one of the rings, in a direction perpendicular to the roller axis, to create a securing region. The securing region prevents relative axial movement of the two rings during the assembly of the universal joint.

A tripod roller is used in a tripod joint having a joint outer part and a joint inner part with three supporting pins. The tripod roller is placed on at least one of the three supporting pins. The tripod roller includes an inner ring, an outer ring, and may include an intermediate ring. The inner ring is placed on a supporting pin. An outer surface of the outer ring bears against the joint outer part. At least one interface between the sliding pin, the inner ring, the intermediate ring, if present, and the outer ring forms a sliding bearing.

A boot includes a large-diameter tubular portion, a small-diameter tubular portion, and a bellows portion. The large-diameter tubular portion includes a fastening groove into which a fastening member is fitted, an opening end to which the bellows portion is coupled and into which an outer case is inserted, at least one seal lip having an annular shape and protruding from an inner circumferential surface of the large-diameter tubular portion at the position where the fastening groove is projected to the inside in the radial direction, so as to be continuous over the entire circumference, and a protrusion protruding from the inner circumferential surface on the opening end side with respect to the seal lip so as to be provided over the entire circumference. A height of the protrusion is set to be smaller than a height of the seal lip.

In a tripod type constant velocity universal joint 1 of a double roller type, R/PCD?0.0850 and t/PCD?0.145, where PCD is a pitch circle diameter of a roller guide surface 6 of an outer joint member 2. R is a radius of curvature at an intermediate portion between a body portion 31 and a leg shaft 32 of a tripod member 3, and t is a minimum distance from a large-diameter portion 34a of a spline 34 of the tripod member 3 to an intermediate portion 33.

fitting a boot 20 to an outer periphery of an outer joint member 2, causing a boot band 100 to circle around an outer periphery of the boot 20, and fastening the boot 20 by reducing a diameter of the boot band 100 are included. A portion (lug portion 111) of the boot band 100 to which a pressing force in an inner diameter direction is applied when the diameter of the boot band 100 is reduced is arranged in a circumferential region R of a thin portion 21S of the boot 20.

A manufacturing method is used for an outer joint member of a constant velocity universal joint. The outer joint member includes a cup section having track grooves formed in its inner periphery, which are engageable with torque transmitting elements, and a shaft section formed at a bottom portion of the cup section. The manufacturing method includes welding the cup and shaft members by irradiating a beam to joining end portions of the cup and shaft members, causing an outer surface including the welded portion to be formed into a flat smooth surface by removal processing, irradiating ultrasonic waves to the flat smooth surface with one probe at an incident angle which prevents total reflection in a circumferential angle beam flaw detection method, and setting a focal point of the ultrasonic waves to positions from a surface to an inside of the welded portion, to thereby perform inspection.

A manufacturing method is used for an outer joint member of a constant velocity universal joint. The outer joint member includes a cup section having track grooves formed in an inner periphery of the cup section, which are engageable with torque transmitting elements, and a shaft section formed at a bottom portion of the cup section. The outer joint member is constructed by forming the cup section and the shaft section as separate members, and by welding a cup member forming the cup section and a shaft member forming the shaft section to each other. The manufacturing method at least includes welding the cup member and the shaft member by irradiating a beam to joining end portions of the cup member and the shaft member, and inspecting a welded portion formed in the welding by a plurality of ultrasonic flaw detection methods with one probe.

In an outer joint member of a constant velocity universal joint, a cup member and a shaft member are made of medium to high carbon steel and welded together. The cup member has a bottomed cylindrical shape that is opened at one end, and includes a cylindrical portion, a bottom portion, and a short shaft section of a solid shaft shape protruding from the bottom portion and having a joining end surface. The shaft member has a solid shaft shape and a joining end surface. The joining end surfaces of the cup and shaft members are brought into abutment against each other, and a high energy intensity beam is radiated from an outer side in a radial direction to form a welded portion. A structure of a molten metal at the welded portion is in a mixed phase of ferrite and granular cementite.

Provided is a method of manufacturing an outer joint member of a constant velocity universal joint, which is constructed by forming a cup section having track grooves, and a shaft section, and by welding a cup member and a shaft member, the method including: forming the cup member and the shaft member of medium carbon steel; preparing a cup member having a cylindrical portion and a bottom portion integrally formed by forging, and a joining end surface in a machining step; preparing a shaft member having a joining end surface formed in a machining step; bringing the joining end surface of the cup member and the joining end surface of the shaft member into abutment against each other; welding the cup member and the shaft member by radiating a beam; and performing, after the welding, an ultrasonic flaw detection-inspection step.

An outer joint member for a joint assembly configured to receive an inner joint includes a wall forming a hollow chamber having a closed end and an open end. A plurality of restrictors are coupled to the hollow chamber each having a portion thereof extending outwardly from the inner surface of the wall of the hollow chamber. The plurality of restrictors extending from the inner surface of the wall proximate the open end of the hollow chamber.