| 摘要 |
PROBLEM TO BE SOLVED: To provide a charging apparatus including discharge means and an electrode for adjusting the amount of charges to be supplied by the discharge means to a body to be charged, configured to detect stain on the electrode more properly and reduce the stain and possible stain.SOLUTION: A control part of an image forming apparatus specifies a voltage applied to a grid electrode of a charging apparatus and a surface potential of a photoreceptor drum. A control part calculates a difference between the specified grid voltage and surface potential. The control part compares the calculated difference with a previous difference. When the current difference is smaller than the previous difference, the control part increments a counter by one. The control part compares a counter value with a threshold. When the counter value is larger than the threshold, the control part determines that stain on the grid electrode is increasing due to sucked outside air, and stops operation of a suction fan. |
