| 摘要 |
PURPOSE:To provide a small-sized ultrasonic motor wherein an electro- mechanical conversion element is not damaged by a stress. CONSTITUTION:This motor is composed of piezoelectric elements 1, 2, of two resonators 4, 10 which sandwich the piezoelectric elements 1, 2 and of a fastening member 5 which presses and fixes the piezoelectric elements 1, 2 and the resonators 4, 10 in their superposition direction. The motor is provided with an ultrasonic vibrator 12 which causes bending vibrations turning around the fastening member 5 when an AC voltage is applied to the piezoelectric elements 1, 2 and with a rotor 13 which is pressed to the resonator 4 and which is driven with reference to the resonator 4 by elliptical vibrations caused at the edge of the resonator 4. The piezoelectric elements 1, 2 are arranged in positions of nodes of the bending vibrations caused by the ultrasonic vibrator 12, and a connecting cylinder part 9 which is extended from the resonator 4 is formed at the inside in the radial direction of the piezoelectric elements 1, 2. |
