PURPOSE: To disengage a clutch with higher accuracy at the time of reaching above a torque limit value by making a cage relatively rotate to release the engagement between a rolling body and wedge-shaped surfaces when a torque above a set torque is applied.

CONSTITUTION: When the load torque of a separating roller 17 is below a set torque, the distortion of a torque setting elastic member 12 is small and a gap A in the rotating direction exists between each rolling body 4 and the wall face of each pocket 9. When a torque above a set torque is loaded on the separating roller 17, the torque setting elastic member 12 is distorted, a cage 2 is relatively rotated clockwise with respect to an inner member 3 until each gap A in the rotating direction is removed, each pocket wall face 11 presses each rolling body 4 to remove its engagement with wedge-shaped surfaces 20, 20', and the separating roller 17 is rotated counterclockwise due to the load torque. Thereby, a limit torque can be accurately set by means of the torque setting elastic member 12.