Patent ID: 8600280

Claim:
A fixing device comprising: a rotating fixing body configured to rotate on an axis extending in a width direction of a recording medium to be conveyed and configured to fix a toner image on the recording medium by heating, the rotating fixing body having a cylindrical metal core formed of a magnetic shunt alloy and having a thickness less than a magnetic-field permeation depth at a temperature higher than or equal to a Curie temperature of the metal core; a coil provided along an outer surface of the rotating fixing body, the coil configured for generating magnetic flux that subjects the rotating fixing body to induction heating; and an electrically conductive arch-shaped saddle ring member, the ring member being disposed at a position opposing the coil with the metal core being disposed therebetween and in an orientation such that magnetic flux leakage associated with loss of ferromagnetism of the metal core penetrates a hollow portion defined by a frame of the ring member to induce in the ring a current that generates a magnetic field that opposes the magnetic flux leakage.