| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus with a fixing unit which can realize both the reduction of a preheating time (warming-up time) and the suppression of the temperature rise at the end during paper passage of a small size without modification of the heat roller itself and without degradation in productivity. SOLUTION: The fixing unit 11 has a fixing roller 20, a heat roller 22 internally having a heater 21 as a heat source, a fixing belt 23, a pressure roller 24, and a tension roller 25. The fixing unit 11 (not illustrated) has a moving means for changing the distance between the heater 21 and the heat roller 22. In the preheating time after a power source is turned on before the surface of the fixing belt 23 reaches a fixable temperature, the heat roller 22 is moved upward by the moving means. As a result, the distance d between the abutting part A of the surface of the heat roller 22 on the side nearer a fixing nip N and the fixing belt 23 and the heater 21 is close, thereby making it possible to heat up the fixing nip N up to the prescribed temperature much earlier. COPYRIGHT: (C)2006,JPO&NCIPI
|
