| 摘要 |
PURPOSE:To control the replenishment amount of toner according to the state of images and achieve the improvement in picture quality by making the voltage to be applied to a recovery roller lower when the images are of high density and high when of low density thereby changing the same at least in two steps. CONSTITUTION:A detecting part 13 which detects the density of the original 8 prior to copying is disposed and this detection signal is compared with a reference density in a comparison part 14, the comparison signal whereof is inputted to a memory part 15. Here, the signal is inputted to a voltage control part 16 only during the time copying is done to change the voltage of a toner recovery power source 36. Namely, in the case of the images of high density of large toner consumption, low voltage is applied to the recovery roller 32 in order to reduce the toner recovery by the recovery roller 32 and in the case of the images of low density of low toner consumptin, high voltage is applied to increase the toner recovery. |
