| 摘要 |
PURPOSE:To replenish toner corresponding to actual toner density by varying the output set value of a toner density detection sensor for toner supply according to the conveying speed of a developer. CONSTITUTION:The output set value of the toner density detection sensor 82 is varied according to the conveying speeds of developer conveying machines 71 and 72 and the start period of the toner replenishment is so adjusted as to supply the toner when a developer passes a supply opening 81. Speed variation is performed when development is performed or not performed or at the time of image density adjustment. The output set value of the sensor 82 is switched by varying a comparative reference voltage. In another way, comparison data corresponding to various conveying speeds for the sensor output are stored in a ROM in a table and the toner supply corresponding to the conveying speed may be carried out according to the stored data. Consequently, uniform toner density is obtained and an image of high quality is obtained. |
