| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device that minimizes the effect of a toner layer during leak detection and is able to apply leak voltages to both an image part and a white part without wasting toner and to provide an image forming apparatus that has a developing device. SOLUTION: A first bias circuit 30 for applying Vslv (DS) and Vslv(AC) is connected to a developing roller 23. A second bias circuit 31 for applying a Vmag (DC) and Vmag (AC) is connected to a magnetic roller 22. A voltage variable device 33 is connected to the first bias circuit 30 and the second bias circuit 31. A leak detector 35 is connected to the first bias circuit 30. In order to detect occurrence of leak, the Vmag (DC) is equally applied to the Vslv (DC) or applied in the direction in which toner moves from the developing roller 23 to the magnetic roller 22. COPYRIGHT: (C)2010,JPO&INPIT |
