| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that stably performs image formation by preventing image failure resulting from a decrease in the height of the level of an agent and a temperature increase of a conveying member in a developing apparatus of a vertical stir configuration. <P>SOLUTION: The image forming apparatus includes: a developing sleeve 28 that conveys two-component developer; a first conveying screw 26 that recovers and conveys the developer after development; a second conveying screw 25 disposed above the first conveying screw 26 and used to supply the two-component developer to the developing sleeve 28; an inductance detection sensor 20 for detecting a toner concentration; and a toner concentration reference value correcting means. In the image forming apparatus, a drive source M1 for driving the developing sleeve 28 and a drive source M2 for driving the first and second conveying screws 26 and 25 are separate drive sources. The apparatus has a control section that controls the rotational speed of the first and second conveying screws 26 and 25 based on an amount of correction of a reference value of an inductance detection sensor 20, which is corrected by the toner concentration reference value correcting means. <P>COPYRIGHT: (C)2010,JPO&INPIT |
