| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus constituted so that the occurrence of an error in controlling toner concentration by an inductance detection sensor can be prevented by estimating the apparent density variation of developer based on an image ratio. <P>SOLUTION: The image forming apparatus is provided with a developer concentration controller 20 for detecting the apparent permeability of two-component developer and actuating a toner replenishing means based on a reference value for a toner replenishing control from the result of a comparison of a detection signal based on the detection result with a detection signal reference value, and a detection signal reference value correcting means for correcting the reference value for the detection signal to a new detection signal reference value based on the number of image forming sheets, the detection signal reference value correcting means is provided with a selecting means for varying the correction quantity of the detection signal reference value based on the integrated value of the outputted value for every image of an image signal. <P>COPYRIGHT: (C)2004,JPO |
