| 摘要 |
PURPOSE:To eliminate such irregular rotation of a vibration-wave motor that the rotating speed of the motor abruptly changes. CONSTITUTION:This drive controller which controls the frequency of a vibration- wave motor based on the phase difference between a driving signal and detected vibrations is constituted in such a way that, when the phase difference is larger than theta2, the speed of the motor is increased by downing the driving frequency of the motor (Step 102) and, when the phase difference is larger than theta2, but smaller than theta1, the variation of the driving frequency is prevented by setting a frequency fixing flag at '1' (Step 109). |
