| 摘要 |
PURPOSE:To correct an error in replenishment by directly detecting the actual toner concentration of a developer in an image forming device information of a picture information signal. CONSTITUTION:A second developer concentration controller is operated whenever one copying action or a consecutive copying action is finished, and a reference image is formed on a photosensitive drum 40, to detect the actual toner concentration of a two-component developer in the developing unit 44 by a light source 73 and a photoelectric conversion element 74. The measurement value of the detected toner concentration and a reference value are compared by a comparator 75, and the value a difference in the comparision is sent to a CPU 67, to calculate over or under toner replenishing time per the images of one sheet, from a table in the CPU 67. The toner replenishing time is subtracted from an estimated toner replenishing time per the images of one sheet, when the replenishment is too much and added when the replenishment is short, to correct the toner replenishing time, at the time of executing the next image forming action. |
