| 摘要 |
PROBLEM TO BE SOLVED: To obtain an excellent image by preventing toner from adhering to a toner electrifying roller and applying stable charge to the toner on a developing roller over a long term. SOLUTION: In cleaning sequence for the toner electrifying roller 18, the voltage V1 of the roller 18 and the voltage V2 of the developing roller 5 maintain potential relation that V1-V2 shows a reverse polarity to the polarity of the toner for a fixed time, and then maintain potential relation that V1-V2 shows the same polarity as the polarity of the toner for the fixed time. The fixed time is set to be equal to or above the time equivalent to one rotation of the roller 18. |
