| 摘要 |
PROBLEM TO BE SOLVED: To properly maintain an image forming state by estimating the mixed quantity of a foreign matter at the inside of a developing device based on an image forming processing condition and an environmental condition, and controlling the storing amount of toner in the developing device in accordance with an estimated result. SOLUTION: The mixing ratio of the foreign matter in the recycled toner removed from the surface of a photoreceptor drum by cleaner at the time of image forming processing is calculated as the characteristic of the recycled toner based on a paper size, an image area and transfer efficiency (s3-s9). Then, in the case of judging that the mixing ratio of the foreign matter in the recycled toner is high and the characteristic of the recycled toner is low, the processing to recover the recycled toner to the developing device is temporarily interrupted (s11→s14), and the toner of a specified amount is conveyed from the developing device to the cleaner (s16 and s18), so that the characteristic of the recycled toner is improved. The recycled toner low in characteristic is prevented from being used for the image forming processing to prevent the deterioration of an image quality. |
