Patent ID: 8185031

Claim:
A fixing device for causing a sheet, on which an unfixed image has been formed, to pass through a fixing nip, and thus thermally fixing the unfixed image onto the sheet, the fixing device comprising: an endless belt that is heated by electromagnetic induction while being driven to rotate; a first roller positioned inside a rotation path of the belt; a second roller operable to form the fixing nip between an outer surface of the belt and the second roller, by pressing the first roller from outside the rotation path of the belt with the belt in between; a guide plate that (i) extends, inside the rotation path of the belt, in parallel with a rotation axis of the first roller, and (ii) guides the belt in a rotation direction thereof by coming into contact with an inner surface of the belt; and a magnetic flux generator that (i) is positioned outside the rotation path of the belt, facing the guide plate with the belt in between, and (ii) generates magnetic flux for heating the belt, wherein the belt includes a heat generation layer that generates heat due to the magnetic flux, and a magnetic shunt alloy layer that reversibly turns from ferromagnetic to nonmagnetic when a temperature thereof has exceeded a predetermined temperature, the guide plate includes a low-resistance and electrically conductive layer, and at least one of ends of the guide plate in the rotation direction is a thick portion having a greater thickness than a central portion of the guide plate.