Patent ID: 9031439
Filing Date: 2015-05-12
Classification: G03G

Abstract:
1. A fixing device comprising: a rotatable fixing member that heats a recording medium on a side carrying an unfixed image; a rotatable pressing member that is pressed and is contacted with the fixing member to form a nip portion between the pressing member and the fixing member; a heat source heating the fixing member; a relay switch provided in an energizing path from a power supplying unit to the heat source; a temperature detection sensor detecting a temperature of the fixing member; and a control unit that controls energization of the heat source according to the temperature detected by the temperature detection sensor, wherein the control unit includes an overheat protection circuit that outputs an abnormal stop signal to stop power supply to the heat source upon the temperature detection sensor detecting an excessive rise in the temperature of the fixing member, and a relay control unit that keeps the relay switch in an off state in which the relay switch is open for a period of time, on condition that the temperature of the fixing member is equal to or more than a predetermined temperature when the fixing member has stopped rotation, and wherein the overheat protection circuit is prevented from outputting the abnormal stop signal to stop power supply to the heat source during said period of time when the relay switch is open.