Patent ID: 8934791
Filing Date: 2015-01-13
Classification: G03G

Abstract:
1. A fixing device for use in an image forming apparatus, the fixing device comprising: a heat rotational member configured to contact a sheet on which a toner image is transferred and to fix the toner image to the sheet; a pressure rotational member configured to press the heat rotational member to form a nip, to apply a pressure to the sheet, which passes through the nip, and to fix the toner image to the sheet; a magnetic-flux generation unit including a detector configured to detect power consumption of the magnetic-flux generation unit; and a fixing controller configured to recognize the power consumption of the magnetic-flux generation unit based on an output of the detector in response to an instruction of a target power applied to the magnetic-flux generation unit from the outside, to set a switching frequency of the switch unit in accordance with the target power if present power consumption of the magnetic-flux generation unit is smaller than the target power, to check a difference between the present power consumption of the magnetic-flux generation unit and the target power, and move the switching frequency closer to a reference frequency until a difference between the present power consumption of the magnetic-flux generation unit and the target power is within a predetermined range by feedback control, and to cause the switch unit to stop the power supply to the resonant circuit if a difference between the switching frequency set in accordance with the target power and the adjusted switching frequency exceeds a predetermined change width during the feedback control.