| 摘要 |
PURPOSE:To accurately control the rotating angle of a rotor by applying a draking voltage from a controller to a voltage ceramic for braking which is bonded to an ultrasonic wave propagation medium at the time of braking. CONSTITUTION:The stator 11 of an ultrasonic wave drive motor contains a ringlike ultrasonic wave propagation medium 13 whose one surface is abutted on a ringlike rotor 12. Driving piezoelectric ceramics 14a, 14b and braking piezoelectric ceramics 15a, 15b are bonded to the medium 13. A driving voltage applied from a controller to the ceramics 14a, 14b is interrupted to be stopped. Driving voltages are respectively applied to the ceramics 15a, 15b to elongate or contract them at this time to elongate or contract the medium 13 in a direction different from that at the time of driving the rotor to transmit an ultrasonic vibration in a direction of an arrow B. As a result, the rotation of the rotor 12 can be braked. |
