| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus that has two or more developing units, the apparatus being designed so as to improve precision in detecting quantities of toner supplied to developing units one of which has a toner supply port furthest from the position, where the quantity of toner is detected and the other of which has a toner supply port nearest this position. SOLUTION: Among the supply ports 91a to 91d made in the developing units 40a to 40d, respectively, the supply port 91a is shortest in the distance of the position where a quantity of toner is detected, whereas for the supply port 91d the distance is the largest. By making the speed of toner supply from the supply port 91a and 91d lower than the speed of toner supply from the supply ports 91b and 91c, errors in the detection of a quantity of toner, generated by these distances, are reduced. COPYRIGHT: (C)2008,JPO&INPIT |
