| 摘要 |
PROBLEM TO BE SOLVED: To satisfactorily keep image quality by preventing electrification conditions for a photoreceptor from changing due to the influence of the potential of a transfer roller, in the toner image transfer part of the image forming device. SOLUTION: To a photoreceptor 21 disposed in a photoreceptor unit 20, negative potential is applied from an electrifying roller 22, thereby uniformly electrifying it. After the formation of a toner image, the image is transferred to paper by the potential of the transfer roller 26. In a power-supply circuit for the transfer roller 26 a power-supply switch unit 32 is disposed, and in response to a signal form a sensor 35 a controller 36 outputs an operation signal for the power-supply switch 32 via a command circuit 37. The power- supply switch circuit 32 applies a voltage to the transfer roller 26 only the length of time corresponding to one or more rotations of the drum early, and thus the potential of the toner image is prevented from changing in the course of the process. |
