Abstract: An RPM-responsive automatic sprag overrunning clutch includes a hub adapted to be attached to a drive shaft, a ring gear surrounding the hub and spaced therefrom, and a plurality of sprags positioned between the hub and the ring gear. An actuator mechanism secured to the hub includes a pair of movable segments and a pair of rollers which are free to move radially of the hub under the influence of centrifugal force as the clutch is increasingly rotated. All the movable segments are connected to an annular plate which is pinned to each of the sprags such that circumferential movement of the movable segments is transmitted to the sprags to shift them into or out of wedging relationship between the hub and the ring gear.

Abstract: An RPM-responsive sprag overrunning clutch which includes a hub adapted to be attached to a drive shaft, a ring gear surrounding said hub and spaced therefrom, and a plurality of sprags positioned between said hub and ring gear. An actuator mechanism secured to the hub which includes a pair of movable segments and a pair of rollers which are free to move radially of said ring gear under the influence of centrifugal force as the clutch is rotated. Said movable segments being connected to an annular plate which is pinned to each of said sprags such that circumferential movement of the movable segments is transmitted to said sprags to shift them into or out of wedging relationship between the hub and ring gear.