Patent ID: 8301051

Claim:
A fixing apparatus, comprising: a rotatable fixing device configured to fix a toner image onto a printing medium with heat and pressure at a pressure contacting section; a heat generating device configured to generate and apply heat to the fixing device, said heat generating device having at least one heat generation section extending in a widthwise direction of the fixing device; a pressurizing device configured to pressure contact the fixing device at the pressure contacting section; an internal temperature detection device arranged within a heat generation region corresponding to the at least one heat generation section and configured to detect temperature of the fixing device; an external temperature detection device arranged at the outside of the heat generation region and configured to detect temperature of the fixing device; and a temperature control device configured to control the heat generating device to approximate the temperature of the fixing device to a target level based on the temperature detected by the internal temperature detection device; wherein heat generation of the heat generating device is stopped one of when temperature detected by the internal temperature detection device reaches a prescribed first high temperature detection limit and a temperature rising amount in a prescribed time period after the first high temperature detection limit is reached exceeds a prescribed threshold, and when temperature detected by the external temperature detection device reaches a prescribed second high temperature detection limit, a temperature rising amount detected in a prescribed time period after the second high temperature detection limit is reached exceeds a prescribed threshold, and the heat generating device continuously generates heat on a maximum heat generation condition for a prescribed time period within the second prescribed time period; wherein said second high temperature detection limit is different than the first high temperature detection limit, and wherein said second high temperature detection limit is automatically changed in accordance with a status of the fixing device.