ROTATING BODY, MEMBER TO BE INSERTED WITH SHAFT, RETAINING MEMBER, AND APPARATUS

A rotating body to be inserted with a shaft includes a holding portion on an end portion of the rotating body to hold the rotating body on the shaft. The holding portion includes a hook to be elastically deformable and detachably hook on a recess of an end portion of the shaft. The holding portion is rotatingly movable, with elastic deformation of the hook, over a convex portion of the shaft that is outside the recess in an axial direction of the shaft. 一种插入轴的旋转体包括在所述旋转体的端部的保持部，以将所述旋转体保持在所述轴上。所述保持部包括挂钩部，该挂钩部可弹性变形并可拆卸地挂钩在所述轴的端部的凹部。所述保持部能够通过所述挂钩部弹性变形，在所述轴的轴向，越过位于所述凹部外侧的所述轴的凸部旋转地移动。