Patent ID: 7490503

Claim:
In a method of producing a rotary member made of a metallic plate by which there is formed, at the center of a plate-like metallic blank, a case-like boss which projects in one direction from the lateral side of the blank, said method comprising the steps of: curving a plate-like metallic blank such that said blank is convex in the direction in which a boss is adapted to project, has a resulting arcuate portion, and an outer peripheral edge portion as well; and restraining the outer peripheral edge portion of the curved blank from extending radially outwardly while bending said resulting arcuate portion of the curved metallic blank in the direction opposite to the convex direction using a plurality of molds to gradually reduce the boss, so that the boss is case-like having an annular flat portion, such that the boss and annular flat portion have substantially the same thickness.