DEVICE AND SYSTEM FOR INDUCTION HEATING

• US 20120305545A1
• Filed: 06/03/2011
• Published: 12/06/2012
• Est. Priority Date: 06/03/2011
• Status: Active Grant

• Current Assignee: Haier US Appliance Solutions, Inc. DBA GE Appliances (Haier Group Company)
• Original Assignee: Haier US Appliance Solutions, Inc. DBA GE Appliances (Haier Group Company)
• Inventors: Brosnan, Daniel, Filippa, Mariano, Johnson, Mark, Steurer, Brian, Shaffer, Timothy
• Granted Patent: US 9,282,593 B2
• Time in Patent Office: Days
• US Class Current: 219/622
• CPC Class Codes: H05B 2213/05 Heating plates with pan detection means
• CPC Class Codes: H05B 6/065 using coordinated control of multiple induction coils
• CPC Class Codes: H05B 6/1272 with more than one coil or coil segment per heating zone
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers

Abstract

An induction heating system comprises inductive rings, which in one example are concentrically wound about a center axis to form a coil array. The inductive rings are situated in the coil array to permit activation of the inductive rings independent of the other inductive rings in the coil array. In one embodiment, the induction heating system includes a control structure with a power supply and switches coupled to each of the inductive rings, wherein activation of the switches permits current from the power supply to flow to the corresponding inductive ring. The induction heating system is amenable to appliances such as ovens and ranges, as well as to cooktops such as free-standing cooktops for countertops.

Claims

1. A heating device for induction cooking systems, said heating device comprising:

an inductive ring array forming a heating zone on which an object to be heated can be positioned, the inductive ring array comprising a plurality of inductive rings that are concentrically disposed across the heating zone, wherein each of the inductive rings is configured to be selectively energized independently from concentrically adjacent ones of the inductive rings in the inductive ring array.

2. A heating device according to claim 1, wherein the inductive ring array is configured to generate a power density profile that is uniform across the heating zone

3. A heating device according to claim 2, wherein the inductive rings are uniformly spaced from one another in the inductive ring array.

4. A heating device according to claim 2, wherein the inductive ring array is configured to generate a first heating ring and a second heating ring radially spaced from said first heating ring, wherein each ring is generated with inductive rings that are concentrically adjacent to one another.

5. A heating device according to claim 1, wherein each of the inductive rings comprises a tap at which power is coupled to the inductive ring.

6. A heating device according to claim 1, wherein the inductive ring array comprises a first inductive ring proximate an outer periphery of the heating zone and a second inductive ring proximate a center axis of the heating zone, and wherein the inductive ring array is configured to conduct power serially between the first inductive ring and the second inductive ring.

7. A heating device according to claim 1, wherein at least one of the inductive rings comprises copper litz wire.

8. A heating device according to claim 1, further comprising an insulator disposed between each of the inductive rings.

9. An appliance, comprising:

an induction element comprising a plurality of inductive rings forming a heating zone on which an object to be heated can be positioned;

a power supply coupled to the induction element;

a switching device coupled to the power supply and to the each of the inductive rings; and

a control device coupled to the switching device and the power supply,

wherein the control device is configured to selectively energize each of the inductive rings by the power supply independently from concentrically adjacent ones of the inductive rings in the heating zone.

10. An appliance according to claim 9, wherein the inductive rings are uniformly spaced across the heating zone.

11. An appliance according to claim 10, wherein the induction rings have a spacing density of at least about 2 inductive rings per radial inch.

12. An appliance according to claim 9, wherein the switching device comprises a ring switch for each of the inductive rings.

13. An appliance according to claim 12, wherein the ring switch is selected from the group consisting of a metal-oxide-semiconductor field effect transistor and a triode for alternating current.

14. An appliance according to claim 12, wherein the inductive rings comprise a first inductive ring proximate an outer periphery of the heating zone and a second inductive ring proximate a center axis of the heating zone, and wherein the switching device is configured to direct power serially between the first inductive ring and the second inductive ring.

15. An appliance according to claim 9, wherein the induction element is configured so that energizing the inductive rings at the same time generates a power density profile that is uniform across the heating zone.

16. An appliance according to claim 9, wherein the induction element is part of a cooktop.

17. An appliance according to claim 16, wherein the cooktop is configured for use on a countertop.