| 摘要 |
PURPOSE:To start smoothly and enhance reliability, by providing the voltage application circuit of an ultrasonic wave motor with positive characteristic thermistors. CONSTITUTION:Into the driving voltage application circuit of the main unit 10 of an ultrasonic wave motor, positive characteristic thermistors 11, 12 are inserted respectively in series, and the main unit is composed so that an input voltage V1, V2 with the phase difference of 90 deg. via the positive characteristic thermistors 11, 12 may be applied to. When the driving voltage V1, V2 is applied to, then great rush voltage is applied to because the thermistors 11, 12 resist low on the initiation, and the main unit 10 of the ultrasonic wave motor is exactly started. After that, a resistance value is suddenly increased by the self-generated heat of the thermistors 11, 12, and with the value and the impedance of the main unit 10 of the motor, voltage is divided, and given limited voltage is applied to. |
