Method of producing a stator yoke of a small-sized motor

摘要

A method of producing a stator yoke of a motor such as an inner rotor type stepper motor, the yoke having a multiplicity of polar teeth. The method has the steps of forming an intermediate blank which has an outer cylindrical portion and an inner cylindrical portion projecting in the same direction, effecting a shearing on the outer peripheral surface of the inner cylindrical portion to cut out a multiplicity of polar teeth arranged at a constant pitch, and effecting a punching to deepen and widen portions between the bases of adjacent polar teeth.