Patent ID: 8529360

Claim:
An outer joint member for a fixed type constant velocity universal joint, the outer joint member comprising: a cup section; and a shaft section extending in an axial direction from a bottom portion of the cup section, the shaft section having a center hole formed at an end surface thereof, wherein the outer joint member is made of machine-structural carbon steel including a carbon component of 0.37 wt % or more and 0.61 wt % or less, wherein the cup section has a radially inner surface provided with track grooves to which balls are fitted, radially inner spherical-surface portions, a cup-inlet chamfer formed along an entire opening periphery of the cup section, track chamfers formed along boundary portions between the radially inner spherical-surface portions and the track grooves, and track-inlet chamfers each of which includes a cutout round portion for alleviating biting of the balls and is provided at a part corresponding to a ball-contact point at an opening end of each of the track grooves, wherein the track grooves, the radially inner spherical-surface portions, the cup-inlet chamfer, the track chamfers, the track-inlet chamfers, a part except for a boot fixing portion on a radially outer surface of the cup section, and the center hole at the end surface of the shaft section are formed by cold-forging finishing without having finishing processes performed thereon after the cold-forging finishing, and wherein two of the cutout round portions for alleviating biting of the balls are provided for each of the track grooves.