JPS5793377A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To maintain surface potential in a uniform state over the entire circumference of a photoreceptor by stopping electrostatic charging upon completion of an ordinary copying process, and performing secondary corona discharging under the conditions differing from those at the ordinary latent image formation after a constant time. CONSTITUTION:A predestaticizer 13, a primary charger 2, a secondary corona discharger 3, and a transfer charger 6 are disposed to a photoreceptor 1. After the point of the time t1 when a copying process ends, the discharger 3 performs discharging and the other chargers are stopped. When the discharger 3 is once stopped at the point of the time t2 when the photoreceptor 1 rotates at the angle between the charger 2 and the discharger 3, the potential of the region (d) drops down to the potential of the region (a). When the stopping of discharging of the discharger 3 is continued until the point of the time t3 when the photoreceptor 1 turns at the angle of the opening width of the discharger 13, the potential of the region (c) drops down to that of the region (a). If the discharging is resumed from the point of the time t3, and the discharger 3 is stopped at the t4 when the photoreceptor 1 turns at the angle corresponding to the charger 6 and the destaticizer 13, the region (b) is destaticized. Thereby, the surface potential of the photoreceptor is made uniform over the entire circumference.