| 摘要 |
PURPOSE:To provide an ultrasonic motor which produces very low noise, can be manufactured at a low cost and operates with a high efficiency. CONSTITUTION:The four corner ridge line parts of the tip surface of the protruding part 8a of a vibration unit 10 are shaped into circular-arc parts 8c. By determining the size of the circular-arc shape to be about ten times of the amplitude of bending vibration by which the vibration unit 10 is excited, an ultrasonic motor which operates with a high efficiency, produces very low noise and has an excellent stability can be realized. With this constitution, a uniform and secure friction contact state between the vibration unit and a moving unit can be obtained, so that an ultrasonic motor which produces very low noise, can be manufactured at a low cost and operates with a high efficiency can be provided. |
