Patent ID: 8472828

Claim:
A fixing device having a fixing member for fixing a developer to a recording medium and a plurality of heating units for heating the fixing member, said fixing device comprising: a temperature detecting unit for detecting a temperature of the fixing member; a first memorizing unit for memorizing a switching temperature for switching a drive of the heating units; a selecting unit for selecting a heating unit among the plural heating units to be driven based on the switching temperature and the temperature of the fixing member detected by the temperature detecting unit; and a heating control unit for selectively driving the heating unit selected by the selecting unit, wherein the plurality of heating units are made of a main heater having a prescribed heat amount and a supplemental heater having a heat amount which is less than the heat amount of the main heater, and wherein the selecting unit selects only the supplemental heater where the temperature of the fixing member detected by the temperature detection unit is equal to or less than the switching temperature, and selects only the main heater where the temperature of the fixing member detected by the temperature detection unit is greater than the switching temperature.