TEMPERATURE CALCULATION METHOD, PROGRAM EXECUTED BY TEMPERATURE DETECTION MEANS, FIXING UNIT HAVING THE TEMPERATURE DETECTION MEANS, AND IMAGE FORMING APPARATUS HAVING THE FIXING UNIT

摘要

PROBLEM TO BE SOLVED: To provide a temperature calculation method which detects infrared rays radiated from a fixing means with a non-contact type infrared sensor and accurately detects the surface temperature of the fixing means on the basis of the result of the detection. SOLUTION: A fixing unit 19 has a heat roller 26 and a pressure roller 27. The heat roller 26 incorporates a halogen lamp 33. A thermopile 35 is disposed without being in contact with the heat roller 26. The fixing unit 19 can accurately calculate the surface temperature T of the heat roller 26 by using the following mathematical expression: T=ä(k1.P+k2+T04)/ε}1/4, wherein P is the voltage level of a thermopile element 350 in the thermopile 35, k1and k2are constants of proportion of P and the proper constants of the thermopile element 350 itself, andεis the infrared ray emissivity of the heat roller 26. COPYRIGHT: (C)2004,JPO