A vibration wave motor for driving a moving member contacting a vibration member, to which an electro-mechanical energy transducer element is bonded, by a travelling vibration wave generated in the vibration member, wherein the moving and vibration members contact each other through a plurality of contact...http://www.google.com.au/patents/US4752711?utm_source=gb-gplus-sharePatent US4752711 - Vibration wave motor
