Optimized motion and location of intense microwave fields within a heating system

Abstract

A method and system for heating a plurality of articles is provided. The method includes discharging microwave energy into a microwave chamber and passing a plurality of articles through the heating zone. At least a portion of the microwave energy discharged into the heating zone may first be phase shifted using one or more phase shifting devices. One embodiment of a rotatable phase shifting device is also provided and includes an elongated fixed member disposed proximate a rotatable housing. The phase shifting device employed by the microwave heating system is configured such that the ratio of the article residence time in the heating zone to the phase shifting rate is at least about 4:1. Rotatable phase shifting devices, or variable phase short circuits, as described herein can also be used in other applications, such as, for example, as impedance or frequency tuning devices.

Dependencies are inferred from the claim text.