| 摘要 |
PURPOSE:To realize proper developer density detection and supplying operation control by storing the density detection position and supply position of a developer relevantly and detecting the abnormality of a developer density detecting device when it occurs. CONSTITUTION:The density signal of each developer detected by a photodetecting element sensor 403 and a reference signal are inputted to a controller 601 through an amplifier 401, an A/D converter 608, and an input/ output port 605. A ROM 602 is stored with the density detection position and supply position of developers relevantly. The controller 601 controls input/output operation while storing necessary data, etc., in a RAM 603 according to the program, data table, etc., in the ROM 602. If the photodetecting element sensor 403 becomes abnormal, that is displayed on a display and operation part 604. |
