METHOD OF AND APPARATUS FOR COLD FORMING TOOTHED WHEELS FROMSHEET METAL

摘要

A one-piece gear with an externally toothed rim extending at right angles to the hub of the gear arid preferably having a smooth internal surface is obtained by converting a circular disc-shaped blank of ductile metallic material into a preform with a concavo-convex or otherwise configurated flange extending to one side of the central portion of the thus deformed blank. The central portion of the deformed blank is clamped between the sections of a first rotary tool while an externally toothed second rotary tool advances radially toward the first tool to convert the flange into an externally toothed rim within a space which is defined in part by a peripheral recess of the first tool and in part by a registering peripheral recess of the second tool.