| 摘要 |
PURPOSE:To prevent the occurrence of high-temperature offset, wrinkles and defective fixation by calculating the temperature of a pressure roller based on the temperature change of a heat roller and correcting a control temperature based on the temperature of the pressure roller. CONSTITUTION:The temperature (tp) of the pressure roller 54b is estimated based on the temperature change of the heat roller 54a, and the control temperature Tc is corrected based on the temperature (tp). That is, an intermittent control for energizing a heater 59 is carried out by combining an on time, or an off time and the control temperature Tc, then, the temperature fluctuation is restrained. And at usual control stage, the control temperature Tc is corrected in accordance with the obtained temperature(tp) of the pressure roller, the control temperature Tc is highly corrected only when the paper passes through, and also, the correction is performed in accordance with an ambient temperature (t0). Thus, the temperature is controlled with a consideration given to the temperature (tp) of the pressure roller 54b, so that the actual fixing temperature is more stabilized even in the case of using a low calorific capacity roller 54a. |
