Patent ID: 7234710

Claim:
A spring powered drive apparatus for a vehicle having at least one wheel on an axle, the apparatus comprised of a braking assembly for selectively preventing rotational movement of the wheel and allowing the wheel to rotate freely, a crank, wherein an external rotational force is applied to turn the crank; a freewheel sprocket coaxially mounted on the axle, the freewheel sprocket freely rotating about the axle in a first direction without communicating rotational force to the wheel and fixedly rotating with the axle in a second direction to provide torque to the wheel; a storage assembly for storing and releasing torque, the storage assembly comprising a helical torsion spring with a first spring end, a second spring end, and a central axis, the storage assembly further comprising a first hub disposed to restrain the first spring end from rotational movement; a torquing assembly receiving rotational force from the crank and applying the rotational force to the second spring end, wherein the spring stores the rotational energy; a releasing assembly comprising: a drive sprocket for transmitting rotational energy to the wheel; a cylinder coaxially positioned along the central axis, the cylinder enclosing the spring therein, the cylinder having a cylinder end attached to the second spring end, the drive sprocket configured for rotational movement with the cylinder about the common central axis, wherein the spring releases rotational energy causing the cylinder and drive sprocket to rotate; and a third power transmission means for transmitting rotational energy provided by the drive sprocket to the freewheel sprocket; wherein the wheel is held immobile while rotational energy is stored in the spring, and the wheel is allowed to rotate with the assistance of the rotational energy communicated by the power releasing assembly.