Smart layered heater surfaces

• US 8,378,266 B2
• Filed: 06/27/2006
• Issued: 02/19/2013
• Est. Priority Date: 06/29/2005
• Status: Active Grant

• Current Assignee: Watlow Electric Manufacturing Company
• Original Assignee: Watlow Electric Manufacturing Company
• Inventors: Steinhauser, Louis P., Ptasienski, Kevin
• Primary Examiner(s): PAIK, SANG YEOP
• Application Number:
  US11/475,534
• Publication Number:
  US 20070000918A1
• Time in Patent Office: 2,429 Days
• Field of Search: 2194431-4682, 219/497, 219/504, 219/505, 219538-548
• US Class Current: 219/443
• CPC Class Codes: A47J 37/0676 electrically heated
• CPC Class Codes: H05B 1/0258 For cooking
• CPC Class Codes: H05B 2203/005 using multiple resistive elements or resistive zones isolated from each other
• CPC Class Codes: H05B 2203/009 Heaters using conductive material in contact with opposing surfaces of the resistive element or resistive layer
• CPC Class Codes: H05B 2203/011 Heaters using laterally extending conductive material as connecting means
• CPC Class Codes: H05B 2203/013 Heaters using resistive films or coatings
• CPC Class Codes: H05B 2203/017 Manufacturing methods or apparatus for heaters
• CPC Class Codes: H05B 2213/03 Heating plates made out of a matrix of heating elements that can define heating areas adapted to cookware randomly placed on the heating plate
• CPC Class Codes: H05B 2213/07 Heating plates with temperature control means
• CPC Class Codes: H05B 3/26 heating conductor mounted on insulating base for transparent areas H05B3/84, H05B3/86
• CPC Class Codes: H05B 3/68 Heating arrangements specially adapted for cooking plates or analogous hot-plates

Abstract

A heater system and related methods of heating a surface are provided by the present disclosure that includes, in one form, a substrate defining a heating surface and a layered heater formed on the heating surface. A plurality of nodes are disposed along the heating surface and are in electrical contact with a resistive heating layer of the layered heater, along with a plurality of lead wires connected to the plurality of nodes. In one form, a multiplexer is in communication with the plurality of nodes through the plurality of lead wires, and a controller is in communication with the multiplexer, wherein the multiplexer sequences and transmits resistances from the plurality of nodes to the controller, and the controller controls an amount of power provided to each of the plurality of nodes based on the differences in resistances between the nodes.

Claims

1. A heater system comprising:

a substrate defining a heating surface;

a layered heater formed on the heating surface, the layered heater defining at least one resistive heating layer;

a grid of nodes having more than two nodes disposed along the heating surface and in electrical contact with the resistive heating layer;

a plurality of lead wires connected to the grid of nodes;

a multiplexer in communication with the grid of nodes through the plurality of lead wires; and

a controller in communication with the multiplexer,

wherein the multiplexer sequences and transmits resistances from the grid of nodes to the controller, and the controller controls an amount of power provided to each of the grid of nodes based on the differences in resistances between the nodes.

2. The heater system according to claim 1, wherein the resistive heating layer is formed from a layered process selected from the group consisting of thick film, thin film, thermal spray, and sol-gel.

3. The heater system according to claim 1, wherein the resistive heating layer defines a trace pattern.

4. The heater system according to claim 1, wherein the resistive heating layer defines a continuous pattern that substantially covers the heating surface.

5. The heater system according to claim 1 further comprising a plurality of heating zones, wherein each heating zone comprises a grid of nodes, and the controller controls the amount of power provided to each of the heating zones based on the differences in resistances between the nodes.

6. The heater system according to claim 1 further comprising a dielectric layer formed on the resistive heating layer but not over the nodes.

7. The heater system according to claim 1, wherein the heating surface defines an outer periphery and the heater system further comprises a plurality of bus bars disposed along the outer periphery, the bus bars being in electrical contact with the resistive heating layer,

wherein the controller controls the amount of power provided to the plurality of bus bars based on the differences in resistances between the bus bars.

8. The heater system according to claim 1, wherein the nodes are formed of a semiconductor material.

9. A heated cooking grill comprising:

a grill body defining a cooking surface and a heating surface opposite the cooking surface;

a layered heater formed on the heating surface, the layered heater defining at least one resistive heating layer; and

a grid of nodes having more than two nodes disposed along the heating surface and in electrical contact with the resistive heating layer,

wherein differences in resistances between the grid of nodes are determined in order to provide requisite power to the grid of nodes as a function of loads placed on the cooking surface.

10. The heated cooking grill according to claim 9, wherein the resistive heating layer defines a trace pattern.

11. The heated cooking grill according to claim 9, wherein the resistive heating layer defines a continuous pattern that substantially covers the heating surface.

12. The heated cooking grill according to claim 9 further comprising a plurality of heating zones, wherein each heating zone comprises a grid of nodes, and a controller controls the amount of power provided to each of the heating zones based on the differences in resistances between the nodes.

13. The heated cooking grill according to claim 9 further comprising a dielectric layer formed on the resistive heating layer but not over the nodes.

14. The heated cooking grill according to claim 9, wherein the heating surface defines an outer periphery and the heater system further comprises a plurality of bus bars disposed along the outer periphery, the bus bars being in electrical contact with the resistive heating layer,

wherein a controller controls the amount of power provided to the plurality of bus bars based on the differences in resistances between the bus bars.

15. The heated cooking grill according to claim 9 further comprising:

a multiplexer in communication with the plurality of nodes; and

a controller in communication with the multiplexer,

wherein the multiplexer sequences and transmits resistances from the grid of nodes to the controller, and the controller controls an amount of power provided to each of the grid of nodes based on the differences in resistances between the nodes.

16. The heated cooking grill according to claim 9, wherein the nodes are formed of a semiconductor material.

17. A method of controlling power to a heating surface in response to a load comprising measuring differences in resistances between a grid of nodes having more than two nodes disposed along the heating surface and in electrical contact with a resistive heating layer of a layered heater, and selectively providing power to the grid of nodes as a function of the differences in resistances.

18. The method according to claim 17, wherein a predetermined power profile is provided to the grid of nodes as a function of the differences in resistance.

19. The method according to claim 17, wherein software determines the differences in resistances.