| 摘要 |
PURPOSE:To surely detect a residual developer at low cost without especially necessitating space. CONSTITUTION:A developing sleeve 22 and a coating roller 29 coating the developing sleeve 22 with toner, are provided. When the developing sleeve 22 is coated with the toner, a developing bias obtained by superimposing a DC on an AC, is applied to the developing sleeve 22 from a power source 104. Thus, a prescribed voltage is induced to the conductive supporting body of the coating roller 29. The residual developer can be detected by the voltage. |
