A pullback motor (also pull back or pull-back) is a simple clockwork motor used in toy cars. A patent for them was granted to Bertrand 'Fred' Francis in 1952 as a keyless clockwork motor. Pulling the car backward (hence the name) winds up an internal spiral spring; a flat spiral rather than a helical coil spring. When released, the car is propelled forward by the spring. When the spring has unwound and the car is moving, the motor is disengaged by a clutch or ratchet and the car then rolls freely onward. Often the clutch mechanism is geared so that the pullback distance needed to wind the spring is less than the distance the spring is engaged propelling forward.