Patent ID: 6871735

Claim:
A reverse-input shutoff clutch comprising: an input-side rotation member; an output-side rotation member; a torque transmission member that can be engaged with and disengaged from said input-side rotation member and the output-side rotation member in both positive and negative rotation directions; a cage for retaining said torque transmission member and switching between the engagement and disengagement of the torque transmission member through the relative rotation of the cage with respect to said input-side rotation member; a stationary-side member; an elastic member for connecting the input-side rotation member and the cage in both positive and negative directions; and rotational resistance applying means for causing slide friction resistance to act on the cage against its rotation with respect to the stationary-side member, wherein rotational resistance of the cage caused by the slide friction resistance is larger than elastic force of the elastic member, and wherein through the control of a rotational phase difference between the input-side rotation member and the cage, the transmission of positive and negative rotational torque from said input-side rotation member to the output-side rotation member is conducted by the engagement of the torque transmission member to said input-side and output-side rotation members, while the transmission of positive and negative rotational torque from said output-side rotation member is shutoff by the disengagement of said torque transmission member.