| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a developing device capable of achieving shortening a time required until toner is supplied after variation of toner concentration is detected, coping with small variation of the toner concentration and suppressing lowering of developing concentration and occurrence of developing irregularities. <P>SOLUTION: The developing device has a developing tank 11, a developing roller 12, a first stirring conveying screw 13 and a second stirring conveying screw 14, a partition plate 15, and a toner concentration sensor 16. The first stirring conveying screw 13 is provided on a side nearer to the developing roller 12 than the second stirring conveying screw 14, and the toner concentration sensor 16 is provided at the end on a downstream side in the conveying direction of the first stirring conveying screw 13 on the side of the first stirring conveying screw 13. A toner supply port 11b is provided in the vicinity of the toner concentration sensor 16 on the side of the second stirring conveying screw 14. <P>COPYRIGHT: (C)2009,JPO&INPIT |
