Patent attributes
A coupling apparatus includes projections projecting axially from circumferential positions on a distal part of an annular body, each projection having an engaging hook projecting in one circumferential direction at an end part thereof. The body and the projections are formed independently of each other, and the apparatus includes a fixing structure for fixing the projections to the positions on the distal part. After inner peripheries of the projections are placed on the outer periphery of the distal part adjacent to an outward overhang, the fixing structure is detachably fixed on the outer periphery in a side of the projections axially opposing to the overhang and has an inward tapering surface fitted on an outward tapering surface of each projection to fix the projections at the predetermined positions on the outer periphery, and includes a cutout exposing the outward tapering surface of at least one projection.
