Patent ID: 7522854

Claim:
A fixing apparatus of an image forming apparatus comprising: an endless heating member having a metallic conductive layer; a pressure member pressed to the heating member to form a nip to hold and convey a medium to be fixed having a toner image in a predetermined direction together with the heating member; an induction heating coil arranged on an outer periphery of the heating member to generate an induced current in the metallic conductive layer; a temperature sensor for detecting a temperature of a passing area of the heating member through the nip; and a controller to control the induction heating coil so as to return the heating member to a predetermined temperature before the nip passing area of the heating member next reaches the nip, wherein the heating member is a fixing belt, and the temperature sensor and the induction heating coil are sequentially arranged on a downstream side of the nip in a rotational direction of the fixing belt, and when a rotational speed of the fixing belt is assumed as S 2 and a response speed of the temperature sensor is assumed as t, distance L from a detection position on the fixing belt by the temperature sensor to the fixing belt opposite to an upstream side end of the induction heating coil is set to L>S 2 ×t.