| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonic actuator having excellent reliability and being capable of considerably restricting any drop in driving efficiency due to pressuring without creating unevenness in speed and decrease in durability even though a pressuring force is increased. SOLUTION: At a position of a neutral plane of bending vibration on a side surface lid of an elastic body 11 of an ultrasonic actuator 10 equipped with drive force take-up portions 11b and 11c and an electromechanical transducer 12 and the elastic body 11 with a flat plate shape, arranged are pressuring members 11e and 11f for pressuring the drive force take-up portions 11b and 11f to a relative motion member, and these pressuring members 11e and 11f are pressured. Biding to the bending vibration by the pressuring members 11e and 11f is restricted and the deflection occurred in the elastic body by pressuring is further restricted. Moreover, by properly selecting the material of the pressuring members 11e and 11f, weather resistance can be enhanced and secular deterioration can be restricted. |
