Abstract: A stacked induction furnace system includes a first furnace having an induction coil to heat and melt a substantially non-conductive material contained in an upper crucible. The upper crucible contains an opening in a bottom surface thereof to drain molten material therefrom. A second furnace is positioned below the first furnace and includes a lower crucible to receive the molten material drained from the opening and is arranged to maintain the molten state of the material in the lower crucible. One or more power sources are provided to power the first furnace and the second furnace.

Abstract: A power supply for a highly inductive load comprises a variable DC source, a unidirectional controlled switching device coupled to the DC source, an inductance in series between the controlled switching device and the load and a capacitance shunting the load. The controlled switching device has a gate coupled to receive a voltage signal functionally related to that across the load so that the controlled switching device will be turned on at the frequency of oscillation of the voltage across the load to provide current pulses to the load.

Abstract: A high frequency power supply circuit for supplying energy to a parallel resonant tank circuit and including a pair of serially connected capacitors having a common terminal connected to the load. The other capacitor terminals are respectively connected to the load through saturable reactors. A substantially constant current bias supply circuit is connected across the other terminals of the reactors and polarized in a manner to produce current flow through the reactors in a direction opposite to that produced by the capacitor discharge. The saturable reactors may comprise a plurality of annular core members disposed on an elongate tubular conductor. Alternatively the reactors may comprise a plurality of core members having an axially extending toroidal winding therearound.