| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ultrasonic motor capable of preventing deterioration in operation efficiency due to temperature rise. <P>SOLUTION: The ultrasonic motor is provided with a stator 1 equipped with a comb-like body 12, a rotatable rotor 2 having a compression welded surface 21a to be compression-welded on a compression-welding surface 12a of the comb-like body 12, and an elastic means 16 for compression-welding the stator 1 and the rotor 2. The ultrasonic motor has a resin film 4 having a frictional coefficient changing depending on at least one of both the compression-welding surfaces. The elastic means 16 is formed of a shape memory alloy, as a compression welding force adjusting means for changing the elastic force of the elastic means 16 in accordance with a change in temperature and keeping a frictional force in the compression-welding surface 4a of the resin film 4 at substantial constant. Even if the frictional coefficient of the resin film 4 decreases due to temperature rise, the compression-welding adjusting means increases the compression-welding force to keep the frictional force on the compression-welding surface 4a of the resin film 4, thereby preventing deterioration in the operation efficiency due to the change in temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT |
