| 摘要 |
PURPOSE:To prevent curling and wrinkling, save electric power, and prolong the life of a roller, bearing motor, etc., by setting the degree of fixation lower in 1st surface fixation than in one-surface image formation, and setting the fixation degree of the 2nd surface lower than that of the 1st surface at the time of both- surface image formation. CONSTITUTION:A heat source 53 is provided with a main heating body 53a and two auxiliary heating bodies 53b and 53c. All the heating bodies are powered on in the fixation of one-surface copying operation, the main heating body 53a and auxiliary heating body 53c are powered on in the 1st surface copying of both-surface copying operation, and only the main heating body 53a is powered on with the signal for the copy start of the 2nd surface. The detection level of a thermistor is varied to control the set surface temperature of the fixing roller 51 to 190 deg.C in the 1st surface copying of both-surface copying operation and 160 deg.C in the 2nd surface copying. Consequently, the heating value applied to a sheet is reduced successively and the degree of fixation is decreased. |
