PURPOSE: To prevent the misoperation of a constant current circuit by inserting a frequency filter for removing a frequency higher than an electrification frequency.
CONSTITUTION: After the surface of a photosensitive drum 1 is electrified to a prescribed dark part potential by an electrifying roller 2, a negative exposure is carried out with laser light 7 whose intensity is modulated, based on a picture signal, and an electrostatic latent image is formed. Then, the latent image has jumping development with one-component magnetic toner by the developing sleeve of a developing unit 6, to obtain a visual image. At such a time, in an AC constant current control system for electrification, at least, a bypass filter (HPF) 4A for cutting the frequency of the electrification frequency or above is connected to a high voltage power source 4 on which the AC constant current circuit 4a and a DC power source 4b are connected in series, in parallel on the AC constant current circuit 4a or a primary electrification closed circuit.
GOTO MASAHIRO
SUWA KOICHI
HIROSHIMA KOICHI
TSUKIDA TATSUICHI
TAKANO MANABU
KATO JUNICHI
INOUE TAKAHIRO
