HIGH FREQUENCY HEATING APPARATUS USING POWER SUPPLY OF SWITCHING TYPE FOR MAGNETRON.

摘要

A high frequency heating apparatus using a power supply of switching type for a magnetron comprises an electric power converter (17) for converting an electric power of a commercial power supply, etc, into a high frequency one, a step-up transformer (18) having a high and a low voltage winding, a magnetron (22) which receives a high and a low voltage output, a resonance circuit (40) connected in series or in parallel with the filament of the magnetron, and a controlling circuit (10). The controlling circuit operates so that on starting, its operating frequency may coincide nearly with the resonance frequency of the resonance circuit. Thereby, the quick starting of the oscillation of the magnetron is realized while preventing the generation of moding by limiting the high voltage value on starting.