Patent ID: 8909084
Filing Date: 2014-12-09
Classification: G03G

Abstract:
1. A fixing device that includes a heating roller incorporating therein heat generating lamps and is configured to heat a sheet having thereon a toner image to fix the toner image, the fixing device comprising: a first heat generating lamp including a first heat generating region; a second heat generating lamp including a second heat generating region in a region that corresponds to a region extending from an end of the first heat generating region and differs from the first heat generating region in an axial direction of the heating roller; a third heat generating lamp including a third heat generating region in a region that corresponds to the region extending from the end of the first heat generating region and differs from the first heat generating region in the axial direction of the heating roller, the third heat generating region having a length different from a length of the second heat generating region, the third heat generating lamp being arranged such that the second heat generating region and the third heat generating region overlap each other in the axial direction of the heating roller; a first temperature sensor arranged closer to an edge of the heating roller than are the first, second and third heat generating regions, the first temperature sensor being configured to detect an edge-portion temperature of the heating roller; a second temperature sensor arranged at a position corresponding to a position where the second and third heating generating regions overlap each other; and a heating control section configured to control heat generation such that detection results of the first and second temperature sensors are constant by selecting one of the second and third heat generating regions based on a detection result only from the first temperature sensor and controlling whether to perform heat generation of the selected heat generation region based on a detection result only from the second temperature sensor.