Microwave Furnace For Thermal Processing

Patent metadata

Field	Value
Publication number	US-2018306512-A1
Application number	US-201815961643-A
Country	US
Kind code	A1
Filing date	Apr 24, 2018
Priority date	Apr 24, 2017
Publication date	Oct 25, 2018
Grant date	—

Abstract

A furnace system includes a heating chamber, a retort assembly, and a waveguide. The heating chamber includes a shell encompassing an insulation layer and a working volume, where the working volume is configured to receive at least one part for heat treatment. The retort assembly is supported within the insulation layer and includes an inner retort surface facing the working volume. The inner retort surface is formed of at least one carbon compound reflective of microwave radiation, and the retort assembly defines a retort aperture. The waveguide is configured to direct microwave radiation from a microwave source to the retort aperture.

First claim

What is claimed is:

1 . A furnace system, comprising:
a heating chamber including a shell encompassing an insulation layer and a working volume surrounded by the insulation layer, the working volume configured to receive at least one part for heat treatment; a retort assembly supported within the insulation layer and having an inner retort surface defining the working volume, the inner retort surface being formed of at least one carbon compound reflective of microwave radiation, the retort assembly defining a retort aperture; and a waveguide extending through the insulation layer, the waveguide being configured to direct microwave radiation from a microwave source to the retort aperture such that at least some of the microwave radiation propagates through the working volume.

2 . The furnace system of claim 1 , further comprising a waveguide insulation occupying an internal volume of the waveguide, the waveguide insulation being substantially microwave transparent.

3 . The furnace system of claim 2 , wherein the waveguide insulation occupies a widthwise span of the waveguide.

4 . The furnace system of claim 3 , wherein the widthwise span is contiguous with the insulation layer.

5 . The furnace system of claim 1 , wherein the inner retort surface is configured to reflectively contain a majority of the microwave radiation within the working volume.

6 . The furnace system of claim 1 , wherein the heating chamber defines at least one chamber aperture, the waveguide extending from the microwave source to the retort via the chamber aperture.

7 . The furnace system of claim 1 wherein the heating chamber defines at least one microwave aperture through the shell that is configured to receive microwave power from the microwave source, and wherein the waveguide extends from the chamber aperture to the retort aperture to direct the microwave radiation into the working volume.

8 . The furnace system of claim 7 , further comprising an insulating wall coupled to the insulation layer and forming a portion of an interior surface of the waveguide.

9 . The furnace system of claim 8 , wherein the portion of the interior surface of the waveguide is formed of at least one carbon compound.

10 . The furnace system of claim 9 , wherein the at least one carbon compound includes graphite.

11 . The furnace system of claim 1 , further including an electrically-resistive heating arrangement disposed between the insulating layer and the retort assembly.

12 . The furnace system of claim 1 , wherein the at least one carbon compound includes graphite.

13 . The furnace of claim 1 , wherein the waveguide includes an inner surface that is substantially reflective of the microwave radiation.

14 . The furnace system of claim 1 , wherein the waveguide includes an inner surface formed of graphite.

15 . The furnace system of claim 1 , wherein the waveguide includes an inner surface lined with a graphite foil.

16 . A furnace system, comprising:
a heating chamber including a shell supporting therein a retort assembly having an inner surface that defines a working volume within the retort, the working volume being configured to receive at least one part for heat treatment, an insulation layer surrounding the retort and configured to provide thermal insulation between the retort and the shell; wherein the working volume configured to receive at least one part for heat treatment; wherein the inner retort surface is formed of at least one carbon compound having sufficiently high conductivity to be reflective of microwave radiation, the retort assembly defining a retort aperture; and a waveguide configured to direct microwave radiation from a microwave source located outside the insulation layer to the retort aperture such that at least some of the microwave power is coupled into the working volume.

Assignees

• Desktop Metal Inc

Inventors

• Woodard Nathan
• Sachs Emanuel M

Classifications

• B32B2255/24

  Organic non-macromolecular coating · CPC title

• H05B6/6491

  combined with the use of susceptors (H05B6/80 and subgroups takes precedence) · CPC title

• F27B5/14

  Arrangements of heating devices · CPC title

• B32B2307/202

  Conductive · CPC title

• B32B3/02

  characterised by features of form at particular places, e.g. in edge regions {(non-uniform thickness B32B3/263)} · CPC title