A motor device utilizing ultrasonic oscillation, which comprises an ultrasonic oscillator including an elastic body and one or more piezoelectric, electrostriction or magnetostriction elements assembled in or on the elastic body, and a movable body movable in a fixed direction. A portion of the ultrasonic...http://www.google.fr/patents/USRE33390?utm_source=gb-gplus-shareBrevet USRE33390 - Motor device utilizing ultrasonic oscillation
