| 摘要 |
PURPOSE:To make low and high speed characteristics compatible and to improve driving efficiency by using a pressing spring, whose spring constant is the specified value or more, for a pressurizing mechanism. CONSTITUTION:When the progressive wave of the bending vibration is ideal, the arbitrary point on a vibrating body 3 undergoes an elliptic motion, wherein the magnitude of the major axis is constant. When there is a standing wave component in the progressive wave of the bending vibration, however, the magnitude of the major axis at the point on the vibrating body 3 is changed. Therefore, a force which strikes a moving body 7 upward acts at the same time as a force for moving the moving body 7. The upward striking force becomes large especially when the moving body 7 is moved at a high speed. When the driving efficiency is decreased, the motion of the moving body 7 becomes unstable. Therefore, drag f' of the upward striking force (f) is generated by using a belleville spring 8, whose spring constant is 1.5kgf/mm or more, and the amplitude value of the up and down vibration of the moving body 7 is made small. Therefore, the ultrasonic motor, whose driving efficiency is high and operation is stable, can be realized. |
