| 摘要 |
PROBLEM TO BE SOLVED: To obtain a rapid rise for a vibration type motor by considering hysteresis characteristics by providing detection means for detecting the initial frequency starting at a high speed of a vibration type motor by a drive circuit. SOLUTION: Start or non-start of a vibration type motor is checked from the output of an encoder 9. If not started, the frequency is sweeped from low side to high side as a warming-up operation and the revolutions is detected (S04). Also, when the start of the vibration type motor is detected, the motor suddenly begins to rotate at a high speed with the frequency available at that time. And a frequency at that time or a slightly high frequency obtained by adding α to the start frequency is stored in the memory (S05). On the other hand, if the initial frequency is stored in the memory (S01), start is performed by applying a voltage of the initial frequency stored in the memory to give a drive state to the motor, and thereafter the motor will be stopped if a stop operation is made as required. |
