| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device that makes excellent printing quality possible by eliminating "rainfall state" in particular, in a developing device using a nonmagnetic one-component developer. SOLUTION: After a motor not shown in Fig. is driven, a bias voltage is applied to an electrifier, a developing roll 35, a feeding roll 34, etc.. The bias voltage applied to the feeding roll 34 during non-printing time is small in potential difference in the absolute value compared with the bias voltage applied to the developing roll 35, thereby suppressing quantity of toner small that is supplied from the feeding roll 34 to the developing roll 35. On the other hand, the bias voltage applied to the feeding roll 34 during printing time is raised, thereby increasing the potential difference relative to the developing roll 35. With this structure, developing defects can be prevented that causes "rainfall state" on account of the toner remaining on the peripheral surface of the developing roll 35. COPYRIGHT: (C)2005,JPO&NCIPI |
