Patent ID: 8213819

Claim:
A fixing apparatus provided in an image forming apparatus and including a fixing roller, the fixing apparatus comprising: a plurality of fixing heaters provided inside the fixing roller and having heat distribution characteristics that are different from each other, and an auxiliary heater provided inside the fixing roller, to which power is distributed only during a warm-up period until the fixing roller in a lower temperature state reaches a predetermined fixing temperature, wherein a temperature distribution in a longitudinal direction of the fixing roller that is heated by the plurality of fixing heaters is low in a partial region, and heat distribution characteristics of the auxiliary heater are such that a heat distribution corresponding to the partial region where the temperature distribution is low in the fixing roller is high, and wherein the plurality of fixing heaters include: a first fixing heater having heat distribution characteristics by which a first heat distribution that mainly heats a center portion region of a predetermined length along the longitudinal direction of the fixing roller is higher than a second heat distribution that mainly heats both end portion regions other than the center portion region, and a second fixing heater having heat distribution characteristics by which second heat distributions that mainly heat the both end portion regions of the fixing roller are higher than a first heat distribution that mainly heats the center portion region; the heat distribution characteristics of the second fixing heater are such that one heat distribution is narrower than the other heat distribution among the second heat distributions that mainly heat the both end portion regions; and the heat distribution characteristics of the auxiliary heater are such that a first heat distribution that mainly heats the one end portion region of the both end portion regions is higher than a second heat distribution that mainly heats a region other than the one end portion region.