Patent ID: 6932205

Claim:
A clutch comprising: an input member to which a rotational torque is input: a driven member; and an engaging element enabling wedge engagement in a circumferential direction between the input member and the driven member, the engaging element being provided in an engaging element housing space formed between the input member and the driven member, wherein the rotational torque is transmitted from the input member to the driven member when the engaging element is engaged in a wedgewise manner in the circumferential direction between the input member and the driven member, and an engagement portion where the engaging element enables the wedge engagement is provided on one side of the engaging element housing space in an axial direction, whereas a disengagement portion where the wedge engagement of the engaging element is cancelled is provided on the opposite side, and operation means for moving the engaging element in the axial direction between the engagement portion and the disengagement portion is provided, wherein the engaging element is a tapered roller, and a retainer for holding the tapered roller is provided between the input member and the driven member so as to be movable in the axial direction, and the engaging element housing space is formed between the input member and the driven member so as to be narrowed on one side in the axial direction and to be gradually enlarged toward the opposite side, and the engagement portion where the tapered roller is engageable in the circumferential direction is provided on the narrower side of the engaging element housing space whereas the disengagement portion where the wedge engagement of the tapered roller is cancelled is provided on the larger side, wherein the tapered roller is provided so that a minor diameter end of the tapered roller is oriented toward the narrower side of the engaging element housing space while the operation means moves the tapered roller forward and backward in the axial direction along with the retainer, and wherein the retainer has a notch for allowing elastic deformation of the retainer in the circumferential direction on its one end.