| 摘要 |
PURPOSE:To eliminate the generation of a hindrance in toner replenishment even if continuous printing is executed and to prevent the degradation in printing by detecting the image density detection patterns formed on a photosensitive body, replenishing the toner at the resulted image density detection value and stopping an image forming operation. CONSTITUTION:The toner is replenished from a toner housing device into a developing tank when the image density detection value of an image density detecting sensor 304 falls to a 2nd reference value or below. The image forming operation is stopped when the image density detection value falls to a 1st reference value or below. The generation of the hindrance in the toner replenishment is obviated in this way even if continuous printing is executed and the degradation in the image quality of printing is obviated. The run-out of the toner in the toner housing device is known and the rapid exchange of the toner housing device is possible. |
