| 摘要 |
PURPOSE:To readily set an electrifying current by integrally providing a detecting means which outputs the photosensitive body electrifying current as a voltage, the grounding terminal of the detecting means, the output terminal of the detected voltage and a connecting terminal which applys a voltage to the detecting means from an outside. CONSTITUTION:A drum jig 38 is an orbicular which is identical with the photosensitive body in shape, makes a conductive substrate 38a expose and insulates inside itself by an insulating layer 38b, and the substrate 38a is grounded through a photosensitive body electrifying current detecting circuit part 40 (shown within a dot line). Hereby, the photosensitive body electrifying current Id which flows through the jig 38 due to the corona discharge from a corona discharger is outputted as a voltage on both edges of a detecting resistor RS. A positive current rectifier circuit, a negative current rectifier circuit and an AC rectifier circuit which are composed of diodes D1, D2 and D3, condensers C1, C2 and C3 and resistors R1, R2 and R3 respectively are connected to the resistor RS in parallel and their outputs are connected to a connector 39 and when the jig 38 is assembled to a copying machine, they are connected to the jig signal terminal of a control circuit 30. Thus an electric current 1d summing up positive and negative DCs and an AC is simultaneously detected and the DC component in the AC component can be detected from the sum of positive and negative components. |
