Inductive HF heating system - has matching transformer mounted between HF generator and inductor and prim. windings of transformer in series and sec. windings

摘要

The self excited HF generator is provided with a parallel resonant circuit, the inductance of which includes the prim. side of the HF transformer (6). The inductor (7) is connected to the sec. side of the transformer for heating a tube (8). The prim. side (4) of the HF transformer consists of two windingse (41, 42) of approximately the same inductance connected in series. Each prim. winding is connected inductively with an isolated sec. winding (51, 52) of the sec. side (5) and the sec. windings (51, 52) feeding the inductor (7) are connected in parallel and have nearly the same inductance. Each prim. and sec. winding are designed similarly and the prim. windings are provided with variable matching tappings (43, 44). ADVANTAGE - Matches workpiece load over wide range.