Patent ID: 8244148

Claim:
A fixing device for fixing a toner image to a sheet selected from a laminated sheet and a non-laminated sheet, comprising: a fixing roller configured to be heated by a heat source; a pressure roller configured to be pressed into contact with the fixing roller; a switcher manually operable to switch a pressing force between the fixing roller and the pressure roller between a first pressing force and a second pressing force lower than the first pressing force; a pressing force detector for detecting the pressing force between the fixing roller and the pressure roller; a temperature detector for detecting a temperature of the fixing roller; a storage device for storing control data indicating a control temperature for the fixing roller predetermined in accordance with the number of sheets passing the fixing device; and a controller for controlling the temperature of the fixing roller to the control temperature by controlling the heat source in accordance with a signal sent from the pressing force detector and for controlling at least one of the rotating speeds of the fixing roller and the pressure roller; wherein the controller controls the rotating speed to a first rotating speed when the pressing force detector detects the first pressing force while controlling the rotating speed to a second rotating speed lower than the first rotating speed when the pressing force detector detects the second pressing force, the control data includes first control data indicating the control temperature under the first pressing force and second control data indicating the control temperature under the second pressing force, the first control data includes a first maximum control temperature indicating the control temperature and constant in relation to an increase in the number of passed sheets, the second control data includes data prepared for the laminated sheet, data prepared for the non-laminated sheet and a second maximum control temperature indicating the control temperature and constant in relation to an increase in the number of passed sheets, the second maximum control temperature is lower than the first maximum control temperature, and the second maximum control temperature of the second control data provided for the laminated sheet is greater than the second maximum control temperature of the second control data provided for the non-laminated sheet.