| 摘要 |
PURPOSE:To obtain the moving speed of an optical system in follow up to the rotating speed of a drum-driving motor by applying the signal corresponding to the rotating angular speed including the fluctuating components in the motor for driving the photosensitive drum as a reference signal from a rotating speed detector to a comparing and error signal amplifier. CONSTITUTION:A comparing and error signal amplifier (expressed as amplifier hereunder) EA is constituted of an operational amplifier OA and resistances R, Ra-Rc. The difference in voltage value between the reference signal S applied to the resistance Ra and the comparing signal Sc applied to the resistance Rb is amplified and outputted. The output signal of the amplifier EA is amplified by a power amplifier PA, and is supplied to a motor Mb for driving the optical system, by which the motor Mb is run. A round loop consisting of the amplifier EA, the power amplifier PA, the DC motor Mb and a rotating speed detector TBGb makes control operation in such a direction where the output signal of the amplifier EA is zero, whereby the scanning speed of the optical system is followed up to the rotating speed of the photosensitive drum motor Ma. |
