Patent ID: 8862010
Filing Date: 2014-10-14
Classification: G03G

Abstract:
1. A fixing device to perform a fixing process involving sandwiching a recording sheet in a fixing nip; heating with pressure the recording sheet in the fixing nip; and fixing a toner image onto the recording sheet, the fixing device comprising: an endless, rotatable belt member; a nip-forming rotary member disposed outside a loop of the belt member and contacting an external surface of the belt member to form a fixing nip; a fixing roller disposed at a backside of the fixing nip inside the loop of the belt member and around which the belt member is rotatably stretched; a heater to heat the belt member at a position different from a position where the belt member is rotatably stretched around the fixing roller; a temperature detector disposed opposite the belt member; a memory device to store an operational history of the heater; and a processor operatively connected to the heater to control the heater, before the recording sheet is passed through the fixing nip, to perform a warming-up operation to raise a temperature of the fixing roller at the backside of the fixing nip based on the operational history of the heater stored in the memory device, wherein the memory device stores a cumulative time of heating retroactively from a current time and the processor controls the heater to perform the warming-up operation when the cumulative time of heating is below a threshold value.