Abstract: A decoupler assembly is provided for allowing an alternator to be rotatably driven by a serpentine belt in an engine of an automotive vehicle and for allowing the speed of the belt to oscillate relative to the alternator. A hub is fixedly carried by a drive shaft from the alternator for rotation therewith. A pulley is rotatably journaled to the hub by a ball bearing member. The ball bearing member includes lubricant for minimizing frictional wear therein. A bare, helical clutch spring is operatively coupled between the hub and pulley for transferring rotational movement from the pulley to the hub during acceleration of the pulley relative to the hub by the serpentine belt and for allowing the hub to overrun the pulley during deceleration of the pulley relative to the hub.

Abstract: A flexible coupling assembly interconnects an output shaft and an input shaft. The flexible coupling assembly includes a first hub operatively coupled to the input shaft for rotation therewith. A second hub is operatively coupled to the output shaft for rotation therewith. A flexible element in the form of a coil spring interconnects the first and second hubs for transferring rotational torque between the first and second hubs while continuously compensating for axial misalignment between the first and second hubs. A retainer is disposed between the flexible element and the first and second hubs for limiting radial deflection of the flexible element during rotation of the flexible coupling. A one-way clutch is operatively coupled between the coil spring and one of the first and second hubs for transferring torque in one rotational direction while allowing the output shaft to decelerate relative to the input shaft in a direction other than the one rotational direction.