| 摘要 |
PURPOSE:To prevent the occurrence of the ununiformity of the deterioration state of a photosensitive body in a paper feeding width direction and to eliminate unevenness in charge retention by idly driving some device in the case that copying processing for a small-sized sheet is continuously performed. CONSTITUTION:The machine is provided with a means for detecting the size of a copying paper, a means for counting the number of copied sheets, a timer and a means for idly driving the photosensitive body 1, an electrostatic charger 11 and a fixing device 5, etc., without performing processing such as exposure and developing, when the number of copied sheets reaches a prescribed number of sheets within a prescribed time. Then, in the case that the copying processing for the prescribed number of small-sized sheets is performed within the prescribed time, the photosensitive body 1 and the fixing device 5 are idly driven. In the case that the copying processing for the small-sized sheets are continuously performed, the unevenness in the thickness of the oxidized layer on the end part and the central part of the photosensitive body 1 is caused, but the central part of the photosensitive body 1 is oxidized by the idle driving, so that the thickness of the oxidized layer is made uniform. The photosensitive body 1 is oxidized by oxygen and ozone, etc., in the air. When an electrostatic charger 11 is operated, the ozone is generated, so that the oxidation on the surface of the photosensitive body 1 is enforced. |
