| 摘要 |
PURPOSE:To improve the reliability in fixing of a toner image with simple constitution, by using an alloy, which can be restored to the original shape, to operate pressurizing and releasing mechanisms. CONSTITUTION:An alloy 2, which can be restored to the original shape, supported on an arm 3 which is rotatable around an arm shaft 4 is brought into contact with the circumferential face in both end parts of a fixing roll 5 through a slip member 7. A backup roll 6 is supported on the other end of the arm 3, and the fixing roll 5 and the arm shaft 4 are supported by a supporting side plate 8. When a heating heater 1 of the fixing roll 5 is turned on and the temperature of the fixing roll 5 reaches a prescribed value, the alloy 2 has the shape changed through the slip member 7 and is expanded, and the backup roll 6 is in the pressurized state; and when the heater 1 is turned off, the alloy 2 is returned to the plastic deformation state to release pressurizing. Consequently, a control mechanism consisting of electric parts or the like is unnecessary, and the reliability is improved. |
