Abstract: A stator is mounted in a housing, and a rotor is rotatable with reference to the stator and rotates with a motor shaft. A flywheel is mounted on and rotatable with the motor shaft. An output shaft is separate from the motor shaft and a stationary member is mounted in the housing and surrounds the output shaft with clearance. A coupling plate and a braking plate are both mounted on the output shaft for rotation therewith, being located axially adjacent the flywheel and the stationary member, respectively. A first electromagnet is associated with the coupling plate and when energized causes frictional engagement of the latter with the flywheel so that the coupling plate and thereby the output shaft are entrained in rotation by the flywheel. A second electromagnet is associated with the braking plate and when energized causes frictional engagement thereof with the stationary member so that the braking plate and the output shaft are braked by frictional engagement therewith.