Patent ID: 7496303

Claim:
A fixing device, comprising: a fixing member having an outer peripheral face with which a sheet to be transported is brought into pressure contact; an exciting coil placed along the outer peripheral face of the fixing member to form an elongated shape with respect to a width direction of the sheet to be transported for induction heating of a heat generating layer of the fixing member; an RF power supply circuit for applying a voltage of a certain drive frequency to the exciting coil so as to make the heat generating layer of the fixing member generate heat through the exciting coil; a degaussing coil placed in a small size sheet non-passing region corresponding to a part of the outer peripheral face of the fixing member with respect to the width direction of the sheet along the exciting coil; a changeover switch for opening or closing the degaussing coil in accordance with a size of the sheet to be transported; and a control section for changing and setting a drive frequency of the RF power supply circuit along with opening or closing of the degaussing coil.