Patent ID: 6488789
Filing Date: 2002-12-03
Classification: C23C,F16C,Y10S

Abstract:
A wheel bearing unit for rotatably supporting a car wheel on a body of a motor vehicle, comprising:a rotary member to which a car wheel is attached, the rotary member having double rows of raceway surfaces; a fixed member fixedly coupled to a mounting member located on a car-body side of the device, the fixed member having double rows of raceway surfaces formed therein so as to be opposite to the raceway surfaces of the rotary member; and double rows of rolling elements interposed between the raceway surfaces of the rotary and fixed members, respectively, wherein at least the rotary member is made of a carbon steel containing 0.60 to 0.80 wt % of carbon, and, in the double rows of raceway surfaces of the rotary member, a surface hardened layer is formed by a high-frequency quenching technique.