| 摘要 |
PURPOSE:To stabilize a developing bias and to form an image of good picture quality having no irregularity in density by providing grounding electrodes to be brought into contact with a dielectric layer on the path of a dielectric on both sides of a developing device. CONSTITUTION:A current from a power source 7 which is based on the on/off operation of a transfer device is trapped by grounding electrodes 13 and 14. Further, a current from an end point 20 which is based on another power source is trapped by the grounding electrodes 11 and 12. Consequently, no current flows to an equivalent resistance part between both grounding electrodes where the development point 4p of a developing roller 4R powered on by a developing bias power source 8 is positioned. Therefore, there is no voltage drop and the development point 4p is held at the ground potential at all times. Those developing biases depend upon only the biasing power source 8, so stable developing operation can be maintained. |
