Apparatus and system for three dimensional infrared gradient heating for curing powder coatings on porous wood products

Patent metadata

Field	Value
Publication number	US-9841232-B2
Application number	US-201414341827-A
Country	US
Kind code	B2
Filing date	Jul 27, 2014
Priority date	Jul 31, 2013
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

The present invention has to do with an apparatus for generating a three dimension heating gradient field for curing powder coated wood products. The three dimension heating gradient field is generated with catalytic heater panels having independently adjustable angles and adjustable heat outputs.

First claim

What is claimed is:

1. An apparatus with a system controller for generating three dimensional infrared gradient heating fields for curing powder coating on a three dimensional powder coated wood product, wherein the three dimensional powder coated wood product includes multiple relatively lower and higher density zones, and wherein the powder coated wood product is conveyed through the apparatus by a conveyor, the apparatus comprising:
at least one first catalytic heater element for generating infrared heat incident upon the powder coated wood product;
at least one second catalytic heater element for generating infrared heat incident upon the powder coated wood product;
wherein the at least one first catalytic heater element and the at least one second catalytic heater element are disposed within the apparatus to generate a three dimensional gradient heating zone when the heater elements are operational; and
wherein the at least one first catalytic heater element and the at least one second catalytic heater element are each independently adjustable by the system controller to change the infrared heat generated by each catalytic heater:
wherein the at least one first catalytic heater element the at last one second catalytic heater element each comprise:
a catalytically active porous layer disposed within the heater element;
at least one heat insulating layer containing fibers disposed below the catalytically active porous layer; and
a sealed plenum chamber having a wall portion facing toward said catalytically active layer wherein said wall portion of said sealed plenum chamber comprises a solid perforated member having an open area of between 0.009 and 0.06 percent of the entire surface provided by a plurality of tiny, substantially equally spaced apart apertures haying a diameter of between 0.02 and 0.1 inch for the passage of a combustible gas there through, in combination therewith of a porous baffle member disposed between said insulating layer and said wall portion for distributing portions of said gas in a direction substantially parallel to said wall portion after passing through said apertures, said baffle member also separating said wall portion from said insulating layer and prohibiting said fibers from emeriti and blocking said apertures to the passage of gas there through.

2. The apparatus as in claim 1 wherein the at least one first catalytic heater element and the at least one second catalytic heater element are each independently adjustable by the system controller to change the angle of incidence of the generated infrared heat incident upon the powder coated wood product.

3. The apparatus as in claim 1 wherein said solid perforated member comprises a metal plate having between about 20 and 40 apertures per square foot of said plate, the sum of the open area provided by said apertures being between about 0.013 and 0.085 square inches per square foot.

4. The apparatus as in claim 3 , wherein the volume of said plenum chamber is sufficient to permit between about 200 volume changes per hour at a gas flow rate of about 3 cubic feet per square foot per hour and 800 volume changes at a gas flow rate of about 6 cubic feet per square foot per hour.

5. The apparatus as in claim 4 wherein the system controller adjusts independent gas flow rates through each of the at least one first catalytic heater elements and the at least one second catalytic heater elements, wherein the independent gas flow rates result in a three dimensional temperature gradient field, wherein the three dimensional temperature gradient field is adaptable to substantially cure coatings within the relatively lower density zones before curing coatings within the higher density zones.

6. The apparatus as in claim 5 wherein the controller is adaptable to adjust the independent gas flow rates in response to temperature sensing.

7. The apparatus as in claim 6 wherein the controller is adaptable to adjust the independent gas flow rates in response to specifications associated with the powder coated wood product.

8. The apparatus as in claim 6 wherein the controller is adaptable to adjust the independent gas flow rates in response to actual or predicted conveyor speeds.

9. A system for generating three dimensional infrared gradient heating fields for curing power coating on a powder coated wood product, wherein the powder coated wood product includes multiple relatively lower and higher density zones, and Wherein the powder coated wood product is conveyed through the system by a conveyor, the system comprising:
a plurality of plenum chambers, wherein each of the plurality of plenum chambers is sufficient to permit between about 200 volume changes per hour at a gas flow rate of about 3 cubic feet per square foot per hour and 800 volume changes at a gas flow rate of about 6 cubic feet per square foot per hour;
a system controller for independently adjusting gas flow rate to 3 cubic feet per square foot per hour or 6 cubic feet per souare foot per hour through each of the plurality of plenum chambers;
a plurality of catalytically active layers, each of the plurality of catalytically active layers in gaseous communication with a corresponding one of the plurality of plenum chambers, wherein the plurality of catalytically active layers are disposed relative to each other to generate a three dimensional infrared heat field; and
wherein the independent gas flow rates and the disposition of the plurality of catalytically active layers result in a three dimensional temperature gradient field, wherein the three dimensional temperature gradient field is adaptable to substantially cure powder coatings within the relatively lower density zones before curing powder coatings within the higher density zones.

10. The system as in claim 9 wherein the system controller is adaptable to adjusting the independent gas flow rates in accordance with at least one dynamic system parameter.

11. The system as in claim 10 wherein the at least one dynamic system parameter comprises a cure rate associated with the powder coating.

12. The system as in claim 10 wherein the at least one dynamic system parameter comprises a conveyor rate in unit length per unit time conveying the powder coated wood product through the three dimensional temperature gradient field.

13. The system as in claim 9 wherein the three dimensional temperature gradient field is generated by the plurality of catalytically active layers is adaptable to impinge at a substantially 45 degrees to substantially 55 degrees angle of incidence to the powder coated wood product.

14. An apparatus with a system controller for generating three dimensional infrared gradient heating fields for curing powder coating on a three dimensional powder coated wood product, wherein the three dimensional powder coated wood product includes a plurality of differing density zones, and wherein the powder coated wood product is conveyed through the apparatus by a conveyor, the apparatus comprising:
at least one first catalytic heater element for generating infrared heat incident upon the powder coated wood product at a first incidence angle;
at least one second catalytic heater element for generating infrared heat incident upon the powder coated wood product at a second incidence angle; and
wherein the at least one first catalytic heater element and the at least one second catalytic, heater element are cooperatively disposed within the apparatus to generate proportional three dimensional gradient heating zones when the heater elements are operational;
wherein the proportional three dimensional temperature heating zones are adaptable to substantially

Assignees

• Chapman Michael J
• Heraeus Noblelight Gmbh

Inventors

• Chapman Michael J

Classifications

• B05D3/0263

  with IR heaters · CPC title

• B05D7/06

  to wood · CPC title

• F26B3/305 Primary

  the infrared radiation being generated by combustion or combustion gases · CPC title

• B05D2401/32

  applied as powders · CPC title

• B27N7/005

  Coating boards, e.g. with a finishing or decorating layer · CPC title