| 摘要 |
PURPOSE:To reduce the cost of a printing device and to reduce its size by allowing variation in the rotating speed of a photosensitive drum even if the rotating speed varies and making control over an electrostatic charger, etc., follow up the variation in rotating speed. CONSTITUTION:The rotating speed of a motor 6 varies in proportion to variation in commercial source voltage. A rotation sensor 8 senses the rotating speed and a signal processing part 19 supplies specific timing and a speed signal to an engine control part 12. The engine control part 12 indicates exposure timing for a light emitting diode corresponding to the timing of said signal supply. Further, the engine control part 12 controls the corona current of an electrostatic charger 2, the bias of a development part, and the corona current of a transfer device 5. A processor is provided in the engine control part 12 to generate a control signal by, so to speak, software, thereby performing the control. |
