| 摘要 |
PURPOSE:To correctly control picture density by cleaning a photosensitive body before a photosensor detects a pattern for detection. CONSTITUTION:A detecting signal from the photosensor 17 is inputted to a CPU 24. Moreover, detecting signals from a photosensitive body sensor 26, a toner concentration sensor 27, etc., are inputted thereto. The CPU 24 controls the actions of main motor, the motor 27 of a cleaning part, a cleaning bias 29, the motor 30 of a developing part, and a toner replenishment motor 31, etc. In this case, a photosensitive body belt 10 is cleaned before the photosensor 17 detects. Thus, the residual toner on the surface of the photosensitive body belt 10 can be removed, and the surface can be uniformly approximate to the initial state. Consequently, the photosensor 17 detects the base of the photosensitive body belt 10 and the pattern for detection more correctly. |
