Toner image fixing device with rotational control of fixing rollers

摘要

A toner image fixing device in an electrophotographic image forming apparatus has a heating roller containing a heater and a backup roller, a surface of which is in contact with a surface of the heating roller. A toner image on the paper is fixed by causing the paper to pass through a contacting portion of the heating roller and the backup roller. The toner image fixing device also has a driving device for supplying driving power to the heating roller or the backup roller to rotate both the heating roller and the backup roller, and a controller. The controller controls the driving section in such a way that both the heating roller and the backup roller begin to rotate intermittently immediately after an electric power supply switch of the apparatus is turned on and heat generation from the heater is initiated, and subsequently begin to rotate continuously when the backup roller achieves one revolution by the intermittent rotation. Alternatively, the rotation speed of the heating roller and backup roller is gradually and continuously increased immediately after electric power is initiated and subsequently reach a constant speed.