| 摘要 |
PROBLEM TO BE SOLVED: To prevent the direction of a rotary shaft from being erroneously recognized by dividing the width in the direction of the rotary shaft of a photoreceptor into a plurality of exposure territories, and comparing the input current value measured after re-electrifying with the reference current value. SOLUTION: When the surface of a photoreceptor drum 1 is electrified by an electrifier 2 input current in proportion to difference of surface potential before and after electrification flows between the photoreceptor drum 1 and GND, and it is detected by an ammeter 1a. However, the generating positions of partial electrified unevenness of the photoreceptor drum 1 can no be understood by this. Hence the surface potential is divided into a plurality of parts and exposed by a dividing/exposing means, re- electrified on a second circuit so as to detect input current in the exposed territory, and the surface potential of the exposed territory is recognized. Further the input current measured by the ammeter 1a is computed by a control part 1b, and output to a comparison part 1b. When a voltage value input as a result of comparison is deviated from the reference voltage value of a memory part 1c, the comparison part 1d outputs to a warning part 1e for warning. Hereby, the direction of the rotary shaft of the photoreceptor drum 1 can be prevented from being erroneously recognized and the surface potential can be accurately recognized. |
