| 摘要 |
<p>PURPOSE:To unnecessitate a speed reducer as well as to accurately set electrostatic capacitance by a method wherein two electrodes are provided with a dielectric interposed between them, and one of the electrodes is displaced by the driving force of an ultrasonic motor. CONSTITUTION:A dielectric 3 is attached to an electrode 1 at the position located between the electrode 1 and an electrode 2 constituting a variable capacitor. The electrode 2 is press-bonded to a stator 4 which performs ultrasonic elliptic vibrations, and the electrode 2 (the rotor of an ultrasonic motor) is driven at a low speed by receiving rotary torque through the intermediary of frictional force generated by the ultrasonic elliptic vibrations of the stator 4. Accordingly, when the stator 4 performs ultrasonic elliptic vibrations by receiving the ultrasonic vibrations from an ultrasonic vibrator, the electrode 2 is moved, and as a result, the electrostatic capacitance of the variable capacitor can be changed. Consequently, a speed reducer is unnecessitated, and an accurate setting of the electrostatic capacitance can be conducted.</p> |
