| 摘要 |
PROBLEM TO BE SOLVED: To accurately control toner concentration by setting a threshold corresponding to the state of a developer. SOLUTION: A control part 18 stores a plurality of threshold groups, composed of a plurality of thresholds set corresponding to time change of the state of the developer 41. Then the toner concentration in initial adjustment of the developer 41 is detected, and the toner concentration is controlled by using a threshold, set according to the integrated number of prints or the integrated rotation time of agitating rollers 45 and 46 corresponding thereto from a threshold group selected, based upon the variation width of the detected value of the toner concentration per unit time in the initial adjustment. COPYRIGHT: (C)2005,JPO&NCIPI |
