| 摘要 |
PURPOSE:To obtain stable images by changing over a replenishing table according to the number of copies and replenishing a toner thereby attaining an adequate toner concn. at the time of initial setting. CONSTITUTION:Screw feeders 7 can be respectively separately driven by motors 8a to 8c selected by the signal from a counter for the number of copies. Namely, the detection output of the toner concn. from a photodetector 9e is inputted to an operation amplifier 11 where the reference output of the toner concn. from a reference value generator 12, i.e., reference voltage source and the detection output from the photodetector 9e are compared. Any of the motors 8a to 8c is driven for the prescribed period of time by this comparison signal. The mismatch quantity of the replenishing table by a change in the flow property of the toner at the time of initial setting is decreased by controlling the rotating speed of the screw feeder 7 for replenishing water, by which the fluctuation quantity of the developer concn. is decreased. The replenishing amt. is increased on lowering of the toner concn., by which the stable output images are obtd. |
