| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a shaft member of a rolling bearing device for a wheel, which can further increase the rigidity and strength of a flange, and can extend a life of a metal mold by dispersing stress generated by a raw material in a cold forging process. <P>SOLUTION: There are formed, at the shaft member 1 of the rolling bearing device for the wheel so as to be coaxial with a rotating axis ZC of a shaft, the columnar shaft 10 at which an inner ring raceway is formed at its outer peripheral surface, a columnar flange base 20 which is formed at one end side of the shaft and larger in diameter than the diameter of the shaft, and an engagement shaft 30 which is formed at a side opposite to the shaft at the flange base and formed into a cylindrical shape almost the same in diameter with the flange base or smaller in diameter than the flange base, and a plurality of flanges 21 radially extended in outer diameter directions are formed at the flange base. Then, a flipper-shaped protrusion M protruding to the direction of the outside diameter is formed at the outer peripheral surface of the flange base 20 between the adjacent flanges 21. <P>COPYRIGHT: (C)2012,JPO&INPIT |
