Patent ID: 7417357

Claim:
An ultrasonic motor comprising: a support unit; a rotor rotatably mounted on the support unit; and a piezoelectric driving unit for driving the rotor to rotate, the driving unit being movably mounted on the support unit and comprising a piezoelectric film and a vibration film contacting with the rotor at an outer-periphery thereof; wherein the piezoelectric driving unit comprises a cover fixedly contacting with the vibration film via a plurality of contacting portions; wherein a plurality of poles extend from the cover and each form a flange at a free end thereof, the flanges contacting with the vibration film; wherein the cover comprises a top and bottom cover arranged at two opposite sides of the driving unit, respectively; and wherein each pole is hollow and defining a mounting hole in the covers, a circular hole is defined in the vibration film corresponding to each mounting hole of the covers, the holes being adapted for extension of fixing elements to secure the covers with the vibration film.