Control system for microwave oven - adjusts power delivered by microwaves and by grill-type heater, top and bottom heaters and extra heater

摘要

The control system regulates the microwave energy supplied and also the heat produced by a grill-type heating element, heating elements in the top and bottom of the oven, and an additional heating element. The grill-type heating elements is switched on during a short initial phase and the top and bottom heating elements are coupled in parallel. Only the grill-type heating element is switched off during the cooking phase. During a post-cooking phase, the top, bottom and additional heating elements are coupled in series. The microwave energy is supplied in intervals throughout these three phases. Changeover contacts are located each side of the top and bottom heating elements and are operated by a shared relay.