Patent ID: 8380098

Claim:
A fixing device for an electrophotographic image forming apparatus, comprising: a heat roller configured to heat a toner image formed on a sheet; a thermistor arranged oppositely to a circumferential surface of the heat roller and configured to indirectly detect a temperature of the circumferential surface of the heat roller by detecting a temperature of the air in the vicinity of the heat roller, without contacting the heat roller; a supporting member having a planar plate-like shape and configured to support the thermistor; and a frame member on which the supporting member is fixed, wherein the thermistor is located at a position above a horizontal plane including a rotational axis of the heat roller and on a downstream side, in a rotational direction of the heat roller, with respect to a vertical plane including the rotational axis of the heat roller, and closer to the vertical plane than the horizontal plane; wherein the supporting member has a securing hole used to secure the supporting member onto the frame member with a securing screw, and an adjusting hole with which an adjusting screw is threaded to adjust a position of the thermistor, wherein the securing hole and the adjusting hole are formed on a same plane of the supporting member, and a normal line to the circumferential surface of the heat roller at a position opposite to the supporting member, an axial line of the securing hole, and an axial line of the adjusting hole are parallel with each other, and wherein the securing screw and the adjusting screw are respectively threaded to the securing hole and the adjusting hole from the same direction with respect to the same plane of the supporting member.