| 摘要 |
PURPOSE:To improve the picture quality and fixing performance of an electrophotographic color copying machine and prevent an offset in full-color copy mode, and save the power consumption in monochromatic copy mode by setting the temperature of a fixing roller high during monochromatic copying operation and the temperature of a pressure roller high during plural-color copying operation. CONSTITUTION:When a full-color copy switch 11 is selected, a heater control circuit 17 turns on heaters 7-9. The temperature of the fixing roller 1 is detected by a thermistor 4 and the heater 7-9 are turned on and off selectively so that the temperature of the fixing roller 1 is 140 deg.. The temperature of the pressure roller 2 attains to 150 deg. because of the watt distribution of the heater 7 and heaters 8 and 9. When a monochromatic copy switch 12 is selected, the heaters 7 and 9 are powered on to control the temperature of the fixing roller 1 to 140 deg. and the temperature of the pressure roller 2 to 120 deg.. The color mixture in full- color mode is improved to improve the picture quality and fixing performance. |
