| 摘要 |
PURPOSE:To properly maintain the toner density in a developer invariably by controlling the toner density in the developer of a developing device based on the difference between the temperatures of a fixing section before and after the paper passes through the fixing section. CONSTITUTION:The paper is fed to a fixing device from a paper feed cassette, and the temperature before the paper passes through the fixing device is received from a thermistor 34 and stored in a RAM 42 as the pre-transit temperature T1. A toner image is formed on the paper by a transfer device, and the formed toner image is heated and fixed by the fixing device. The temperature after the paper passes through the fixing device is received from the thermistor 34 and stored in the RAM 42 as the post-transit temperature T2. A controller 40 calculates the difference between the pre-transit temperature T1 and the post-transit temperature T2 and refers to a temperature control table stored in a ROM 41 based on the result. The toner density control is corrected based on the detection signal of a toner density detection section 29 according to the obtained value of the temperature control table. |
