Patent ID: 8903295

Claim:
A fixing device comprising: a fixing member including a conductive layer and that fixes toner on a recording material while the conductive layer is induction-heated; a magnetic-field-producing unit including an exciting member that produces an alternating-current magnetic field intersecting the conductive layer of the fixing member, and first magnetic-circuit-producing members that each produce a magnetic circuit of the alternating-current magnetic field produced by the exciting member, the first magnetic-circuit-producing members including members provided at a predetermined first interval in a longitudinal direction of the fixing member and members provided at a second interval in the longitudinal direction of the fixing member, the second interval being smaller than the first interval; a temperature measuring device provided in contact with an inner circumferential surface of the fixing member and that measures the temperature of the fixing member; and a second magnetic-circuit-producing member having a cut portion in which the temperature measuring device is provided, the second magnetic-circuit-producing member being in contact with the inner circumferential surface of the fixing member and producing a magnetic circuit of the alternating-current magnetic field produced by the magnetic-field-producing unit, the second magnetic-circuit-producing member conducting heat to the fixing member by being induction-heated, wherein the first magnetic-circuit-producing members at the second interval are provided on both sides of a position corresponding to the cut portion of the second magnetic-circuit-producing member in a direction in which the magnetic circuit is produced, and the first magnetic-circuit-producing members at the first interval are provided at other positions.