| 摘要 |
PURPOSE:To greatly increase the using efficiency of current, by insulating a shield, applying an AC high voltage power source to a metallic wire within the shield via a capacitor and at the same time grounding the metallic wire via a diode and a resistance. CONSTITUTION:A metallic wire 3 and a shield 2 are positively electrified with the positive half cycle applied from an AC power source 5. While the negative voltage is applied for a short time to the wire 3 by the time constant of a cirxcuit comprising a resistance 7 and a capacitor 4 in the next negative half cycle. Thus the discharged current flows from the wire 3 to a photoreceptor 1 to electrify the photoreceptor 1 to the positive charge. At the same time, the shield 2 that is electrified to the positive charge in the previous half cycle is neutralized. Accordingly no effect of the previous discharge is left to the shield 2, and at the same time the amount of charge to electrify the shield 2 can be reduced since the ground electrostatic capacity of the shield 2 is small, and most of the discharged current flows to the photoreceptor 1. In such constitution, the using efficiency of current is increased. |
