| 摘要 |
PURPOSE:To complete setting in a short time by setting a reference value by considering a stable value in advance in the case of setting the reference value at the time of initially using a developer in an inductance ATR (controller). CONSTITUTION:In a developing device provided with a toner concentration controller which replenishes toner by comparing an output value in accordance with the toner concentration of developer obtained by mixing carrier and toner with the reference value previously set, a value obtained by subtracting 0.5V from the output value outputted one minute after stirring is set as the reference value. Namely, the setting is not performed after performing stirring for about twenty minutes, and the setting is completed for one minute. Thus, the stirring is performed with other sequence after completing the setting. That means, as to an inductance ATR head 19, analog output obtained by detecting developer concentration is converted to digital output by an A/D converter 20, and the toner replenishing screw 23 of a hopper for replenishing the toner is rotated so as to replenish the toner for the time corresponding to the difference between the signal value and the reference value. |
