Patent ID: 6889991

Claim:
A drive for a wheelchair having a chair frame, a pair of lesser diameter wheels mounted to the frame at a front base section thereof, and two larger diameter drive wheels with axles mounted to the frame at a rear section thereof, the drive mechanism with regard to each drive wheel comprising: (a) first and second disks flanking the drive wheel, each disk defining a contact surface and being in fixed rotational relation with the drive wheel about the axle; (b) a lever having a lever axis, the lever rotatable about the axle and about the lever axis; (c) a cam selectively rotatable about the lever axis by the lever to and from a first contact position and a second non-contact position with respect to the contact surface of the first disk, wherein said cam includes an opening and said lever is inserted within said opening; and (d) a shoe positioned for contacting the contact surface of the second disk when the cam is in the first position, thereby sandwiching the drive wheel in relation between the cam and the shoe, the drive wheel released from the sandwiching relation upon lever rotation of the cam about the lever axis to the second position, wherein the drive wheel is propelled upon lever rotation about the axle when the drive wheel is in the sandwiching relation.