Patent ID: 8113030
Filing Date: 2012-02-14
Classification: B21D

Abstract:
1. A method for manufacturing a work having a peripheral flange by pressing a sheet material, comprising: half die cutting the sheet material so as to simultaneously form inner and outer circumferential surfaces of the peripheral flange while the peripheral flange is simultaneously subjected to isostatic pressures that are directed from at least one of a flange inner surface to a flange outer surface and from the flange outer surface to the flange inner surface, wherein a toothed portion is defined on the flange inner surface, and wherein when the half die cutting is performed, an inner connecting portion that interconnects the peripheral flange and a base portion of the work is formed such that the peripheral flange annularly encircles the base portion, an outer connecting portion that interconnects the peripheral flange and a material portion positioned outside the peripheral flange is formed, and the outer connecting portion has a thickness thinner than a thickness of the inner connecting portion.