| 摘要 |
PURPOSE:To know clearly that the developer of a selected developing device decreases in quantity below a specific value without any error by making a display when the quantity of the developer in the developing device selected among plural developing devices which perform image formation selectively decreases below the specific value. CONSTITUTION:A black developing device 321 and a color developing device 322 are driven selectively through a color selection key. Developers G1 and G2 are supplied to those developing devices 321 and 322 from developer supplement ports 501 and 502 of developer supplementing parts 341 and 342 through developer supplementing rollers 521 and 522. A permanent magnet fitted to an operating element 119 united with a detection lever 118 which is rotated and displaced according to the amount of the developer in a hopper 512 comes close to a reed switch 121, and then the remaining amount of the developer G2 is detected. A hopper 511 is the same. A display device which displayes a decrease in the quantity of a developer below the specific value are fitted to the lid bodies 1331 and 1332 of the hoppers 511 and 522 and driven through a switch 121. |
