| 摘要 |
PURPOSE:To utilize consumed electric power effectively and to obtain excellent fixing by performing high/low switching of electric power supplied to a pressure roller according to a signal for controlling the surface temperature of a heat roller. CONSTITUTION:The heat roller 1 and pressure roller 4 incorporate heaters H1 and H2 respectively and the triac TRC of the heater H1 is turned on and off by a signal from a temperature detecting element TH to hold the surface temperature of the heat roller 1 constant. A normally open contact RA-1 is closed and is made to heat the pressure roller 4 for warming-up operation wherein the heat roller rises in temperature up to a prescribed value. Then, a normally closed contact RA-2 is closed and is made to impress the secondary-side stepped-down voltage of a transformer TR, reducing power consumption. Thus, the consumed power of a copying machine, etc., is utilized effectively to heat the heat roller and quantity of heat from the heat roller surface to the pressure roller is reduced to use it effectively for toner fusion, thereby improving the fixing performance. |
