| 摘要 |
PURPOSE:To replenish the toner of a proper quantity into a developing unit even if a toner concentration inside the developing unit tentatively has dispersion and to shorten the energizing time of an electromagnetic solenoid changing the housing capacity of a container housing the toner completely used by intermittently operating it. CONSTITUTION:The toner concentration inside the developing unit is detected by a magnetic sensor 3c, the replenishing quantity of the toner from a toner box 4 is controlled based on the detected toner concentration and its changing quantity, and simultaneously, the switching of the operation/nonoperation of the electromagnetic solenoid 9b changing the housing capacity of a waste toner bottle 9a is controlled. |
