To improve joining force of a shaft body and a cam piece.

The tubular shaft body 10 in which protruded parts 13 are formed on the outer periphery, and the cam piece 20 in which recessed parts 24 are formed on the inner periphery of an axis hole 23, are provided. The protruded parts 13 are forced to mesh into the recessed parts 24 by enlarging and deforming the shaft body 10 by bulge machining in a state that the shaft body 10 is penetrated into the axis hole 23, while the protruded parts 13 and the recessed parts 24 are being fitted. By this, the shaft body 10 and the cam piece 20 are connected integrally rotatably. Since the protruded parts 13 are formed on the outer periphery of the shaft body 10, and the protruded parts 13 are made so as to fit to the recessed parts 24 of the axis hole 23, even if an amount of enlarging and deforming of the shaft body 10 is small; jointing margins of the protruded parts 13 and the recessed parts 24 can be secured widely.