Magnetic flux driven heat generation member with magnetic flux adjusting means

摘要

An electromagnetic induction heating apparatus capable of uniformize a temperature distribution in a longitudinal direction of an induction heating member includes: an exciting coil (magnetic flux generation means); a fixation roller (induction heating member) for generating heat by electromagnetic induction heating by action of magnetic flux generated by the exciting coil the induction heating member heating a material to be heated through heat generation thereof by introducing the material to be heated into a heating portion and conveying the material to be heated in contact with the fixation roller; and magnetic flux shielding plate (magnetic flux adjusting means) for changing a distribution of a density of an effective magnetic flux which is the magnetic flux generated by the exciting coil and actable on the fixation roller, in a longitudinal direction of the heating portion perpendicular to a conveyance direction of the material to be heated. The magnetic flux shielding plate adjusts the effective magnetic flux so that the effective magnetic flux at a central portion of the fixation roller in the longitudinal direction of the heating portion is less than that at an end portion of the induction heating member in the longitudinal direction.