Patent ID: 7778557
Filing Date: 2010-08-17
Classification: G03G

Abstract:
1. A fixing apparatus comprising: a heating roller; a first sensor configured to detect radiant heat from the heating roller; a second sensor configured to detect an ambient temperature of the first sensor; a computing circuit configured to compute, on the basis of output values of the second sensor, second sensor output correlation threshold values indicated by a plurality of threshold lines each of which is set within a range between one temperature curve and another temperature curve among a plurality of temperature curves that previously show correlations between output values of the first sensor, output values of the second sensor, and surface temperatures of the heating roller; a detecting circuit configured to detect a threshold line corresponding to the output values of the second sensor among the plurality of threshold lines; a controlling circuit configured to control a temperature provided to the heating roller based on a comparison result between the second sensor output correlation threshold values computed by the computing circuit based on the threshold line detected by the detecting circuit and the output values of the second sensor; and a fixing unit configured to heat a sheet where an image by a developer has been transferred by the heating roller so as to fix the image on the sheet.