Abstract: The induction heating apparatus comprises a DC source, a series oscillation circuit including a heating coil and a capacitor connected across the DC source, a diode having an opposite polarity with respect to the polarity of the DC source and connected in parallel with the capacitor and a transistor having a collector-emitter path connected in parallel with the capacitor. The conduction state of the transistor is controlled by a control circuit responsive to the output of a current detector which detects the direction and magnitude of the current flowing through the heating coil.

Abstract: An induction heating apparatus comprises a DC power source, a series resonant circuit of a heating coil and capacitance connected between the terminals of the DC power source, a diode connected in parallel with the capacitor and in polarity-reversed relation to the DC power source, a transistor having a collector-emitter path connected in parallel with the capacitor, and a control circuit for controlling the conductive state of the transistor in accordance with the magnitude and direction of a current flowing through the heating coil.