MANUFACTURING METHOD OF ROTATING ELEMENT, CONNECTING STRUCTURE BETWEEN ROTATING ELEMENT AND ROTATING SHAFT, AND STEERING APPARATUS

摘要

A manufacturing method of a rotating element including a cylindrical fitting portion having a pair of circumferential end portions forming an axial slit between the circumferential end portions, the cylindrical fitting portion being serration-fitted to a rotating shaft, includes: clamping the fitting portion (21, 21M) by a clamp jig (30) so that the fitting portion (21, 21M) is elastically deformed in an elliptical shape; forming a female serration (27) arranged in an elliptical shape by use of a tool (50) having an elliptical section, the female serration (27) being formed on an inner peripheral surface (21b) of the fitting portion (21, 21M) elastically deformed in the elliptical shape; and releasing the clamping by the clamp jig (30) so that the arrangement of the female serration (27) is changed to a perfect-circle shape from the elliptical shape.