| 摘要 |
PURPOSE:To reduce a diameter, and to increase torque by resonating and driving a piezoelectric longitudinal vibrator and a piezoelectric torsional vibrator. CONSTITUTION:Piezoelectric ceramics 1 for exciting longitudinal vibrations is held and unified by columnar ultrasonic vibrators 2, 3, thus forming a piezoelectric longitudinal vibrator as a whole. Piezoelectric ceramics 4 for exciting torsional vibrations are held and integrated by columnar ultrasonic vibrators 5, 6, thus shaping a piezoelectric vibrator as a whole. A rotor 7 is pressure- welded by the longitudinal vibrator and the torsional vibrator. The longitudinal vibrator and the torsional vibrator are made so that their resonance frequencies are equalized. Accordingly, an ultrasonic motor simultaneously resonates and drives the longitudinal vibrator and the torsional vibrator, and the phase difference of 90 deg. is given, thus turning the rotor 7, then acquiring a rotational output. |
