Patent ID: 7520056
Filing Date: 2009-04-21
Classification: B21D,Y10T

Abstract:
1. A method of forming a wheel rim hump portion along a circumferential direction on an outer circumferential wall surface of a vehicular wheel rim gripped by gripping means, comprising the steps of: supporting said vehicular wheel rim from the outer circumferential wall surface thereof with a first die surrounding the vehicle wheel rim and having a recess, and pressing said vehicular wheel rim from an inner circumferential wall surface thereof with a ridge disposed on a second die coupled to a rotational shaft at a position corresponding to said recess to raise the outer circumferential wall surface of said vehicular wheel rim; and rotating said rotational shaft to displace said ridge along the circumferential direction on the inner circumferential wall surface of said vehicular wheel rim, thereby raising said outer circumferential wall surface along the circumferential direction to form a hump portion.