| 摘要 |
PURPOSE:To alleviate an impact such as the start position of an optical system by providing a plurality of reference frequency signals, selecting them, and smoothly controlling the speed of a drive motor of the optical system or a photosensitive member. CONSTITUTION:An oscillator 1 outputs a clock signal of the prescribed frequency, a CPU8 divides the frequency of the signal, and uses the divided signal as a reference frequency signal (FS signal) for moving a drive motor 2 of an optical system and a drive motor 3 of a photosensitive drum. The frequency of the FS signal is not constant but depends upon the speeds for driving the motors 2, 3. The CPU8 compares the frequency signal (FG) generated by speed detectors 6, 7 with the FS signal to detect the phase difference and the speed difference, thereby controlling the motors 2, 3. |
