Method for manufacturing outer joint member for constant velocity universal joint, shaft member and outer joint member

A method of manufacturing an outer joint member of a constant velocity universal joint, which is constructed by forming, through use of separate members, a cup section having track grooves formed at an inner periphery of the cup section and engageable with torque transmitting elements, and a shaft section formed at a bottom portion of the cup section, and by welding a cup member forming the cup section and a shaft member forming the shaft section,

• the method comprising:
• forming the cup member and the shaft member of medium carbon steel;
• preparing, as the cup member, a cup member having a cylindrical portion and a bottom portion integrally formed by forging, and a joining end surface formed on an outer surface of the bottom portion in a machining step after the forging;
• preparing, as the shaft member, a shaft member having a joining end surface to be joined to the bottom portion of the cup member, which is formed in the 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;
• and
• welding the cup member and the shaft member by radiating a beam from an outer side of the cup member to an abutment portion between the cup member and the shaft member in a radial direction of the cup member,
• wherein the shaft member has a step portion in which the joining end surface is formed and a radially inner side recessed portion formed thereon by forging from a billet cut from a bar material.