| 摘要 |
PROBLEM TO BE SOLVED: To prevent the phenomena of down time, and cold offset or hot offset from occurring by selectively switching the pressing force of a pressing roller in accordance with the kinds of toner having different color tone to be fixed by means of a swithcing mechanism. SOLUTION: As to a pressing lever 26; its base end is rotatably and pivotally supported on a side board 33 by a pivot 27, and its free end is combined to the lower end of the elastic member 31 of the mechanism 28 for switching the pressing force of the pressing roller. In the case of using black toner, a cam 37 is on a first pressing position; in the case of two-color mode for simultaneously using the black toner and red toner, the cam 37 is on a second pressing position; and in the case of using the red toner, the cam 37 is on a third pressing position. The pressing condition of the pressing roller 24 need not be changed in the case both black and red toner have the same fixing property however, the fixing property of the used toner is different, so that large pressing force is set in the case of the red toner. |
