Patent ID: 7664416
Filing Date: 2010-02-16
Classification: G03G

Abstract:
1. An image recording apparatus having a fusing unit for heat fusing a toner image onto a predetermined print medium by heating and pressurizing the print medium, the image recording apparatus comprising: at least first and second heater members having different heat distributions, said heater members disposed in said fusing unit in order to apply heat onto said print medium; a temperature detecting unit for detecting a temperature of an area where said print medium passes through said fusing unit; a heat controlling unit for controlling said fusing unit at a prescribed temperature by a heat controlling of said heater members, using independent respective control signals, on the basis of the temperature detected by said temperature detecting unit; a rate determination unit for determining a divisional rate of heat to be supplied per unit time by said fusing unit by means of said heater members; and a condition input unit for inputting a fusing condition of said fusing unit; wherein said rate determination unit determines the divisional rate of the heat to be supplied per unit time by said fusing unit by means of said heater members on a basis of the fusing condition inputted by said condition input unit; wherein said heat controlling unit controls heating of said heater members, using independent respective control signals, on a basis of the divisional rate determined by said rate determination unit; and wherein the image recording apparatus and first and second heater members are configured so that, when the first and second heater members are on, a minimum of a heat distribution at a central portion of the first heater member is lower than maximums of heat distributions at end portions of the first heater member and higher than maximums of heat distributions at end portions of the second heater member, and a maximum of a heat distribution at a central portion of the second heater member is lower than maximums of heat distributions at end portions of the first heater member and higher than maximums of heat distributions at end portions of the second heater member, wherein the central portions of the first and second heater members each correspond to a region of a minimum width of a usable printing medium, and each of the end portions of the first and second heater members corresponds to a region between an end of the region of a minimum width of a usable printing medium and an end of a region of a maximum width of the usable printing medium.