Abstract: An induction heating apparatus has a coil or coils which can be opened without using electrical contacts. One continuous electric current passageway is formed by a first coil section, a second coil section, a first connecting conductor and a second connecting conductor. By feeding electric power to this electric current passageway and passing an object through a space at the central portion of the coil sections, the object is induction heated. A gap is provided between the first connecting conductor and the second connecting conductor, or the respective connecting conductors can be opened and closed relative to one another to vary the size of the space therebetween. The object to be heated is carried into the space at the central portion of the coil and is carried out therefrom through the gap or the space between the conductors.

Abstract: An induction heating apparatus is disclosed which includes a high frequency power source having a leading phase angle setting circuit, which is supplied with a detection voltage signal from an output side of a high frequency inverter connected to a load circuit, to supply a leading phase angle signal to gates of thyristors of the inverter. The high frequency power source further includes a phase control circuit, provided after the voltage detection circuit, which is supplied with the detection voltage signal from the output side of the inverter to periodically control a phase of the detection voltage signal. The induction heating apparatus further includes a series inductor provided in between the power supply bus line connected to an induction heating coil wherein a magnetic member is provided to be inserted into and taken out of the inductor. A drive device is included for driving the magnetic member.