Stephen Duane Swanson

US Patent:

49408658, Jul 10, 1990

Filed:

Oct 25, 1988

Appl. No.:

7/261865

Inventors:

Andrew J. Johnson - Boulder CO
Robert D. Petersen - Thornton CO
Stephen D. Swanson - Brighton CO

Assignee:

The United States of America as represented by the Department of Energy - Washington DC

International Classification:

H05B 680

US Classification:

219 1055A

Abstract:

An apparatus is provided for heating and melting materials using microwave energy, and for permitting them to solidify. The apparatus includes a microwave energy source, a resonant cavity having an opening in its floor, a microwave energy choke encompassing the opening in the floor of the cavity, a metal container to hold the materials to be heated and melted, a turntable, and a lift-table. During operation, the combined action of the turntable and the lift-table position the metal container so that the top of the container is level with the floor of the cavity, is in substantial registration with the floor opening, and is encompassed by the microwave energy choke; thus, during operation, the interior of the container defines part of the resonant cavity. Additionally, a screw feeder, extending into the cavity and sheltered from microwave energy by a conveyor choke, may convey the materials to be heated to the container. Also, preferably, the floor of the resonant cavity may include perforatins, so that the offgases and dust generated in the apparatus may be removed from the resonant cavity by pulling outside air between the container choke and the exterior wall of the container into the resonant cavity and out from the cavity through the perforations.