| 摘要 |
PROBLEM TO BE SOLVED: To obtain an ultrasonic motor and a rotor used therein wherein the efficiency of the motor is enhanced by producing relatively large torsional vibration in the rotor as well. SOLUTION: The ultrasonic motor produces elliptic vibration in a stator 8 by synthesizing longitudinal vibration and torsional vibration generated based on the longitudinal vibration, and rotates an almost columnar rotor 10 brought into contact with the stator 8 in specified direction of rotation based on the elliptic vibration. The rotor 10 is provided with slits 12 for converting longitudinal vibration into torsional vibration. The slits 12 are provided with a first opening at the circumferential face of the rotor 10, a second opening at one end face on the side where the rotor 10 is in contact with the stator 8, and a third opening at the other end face 10a of the rotor 10 and connects to the second opening. The slits 12 are so designed that the position of the first opening is displaced in the direction of rotation as it goes from the one end face toward the other end face. |
