| 摘要 |
PURPOSE:To obtain a predetermined direction of rotation, even when notches of a piezoelectric vibrator are arbitrarily aligned, by providing a plurality of piezoelectric vibrators, each having 4n(n: integer) poles, in a stator. CONSTITUTION:A stator 5 and piezoelectric vibrators 6, 7 are provided inside a bracket 2, and ultrasonic vibration is generated by the piezoelectric vibrators 6, 7 and transmitted to a rotor 4 by the stator 5 to convert vibration of the rotor into a rotary motion. When for the number of poles of the piezoelectric vibrators 6, 7 is assumed to be 4n(n: integer) and notches thereof are arbitrarily matched such as P and R, Q and S or P and S, Q and R, the relative positions of the poles of the piezoelectric vibrators are always fixed and the advancing direction of the traveling wave fixed. In this way, a direction of rotation of the rotor can be determined in one direction. |
