Microwave oven heating element having broken loops

• US 6,114,679 A
• Filed: 09/29/1998
• Issued: 09/05/2000
• Est. Priority Date: 01/29/1997
• Status: Expired due to Term

• Current Assignee: Graphic Packaging International Incorporated
• Original Assignee: Graphic Packaging Corporation
• Inventors: Lai, Lawrence, Zeng, Neilson
• Primary Examiner(s): Leung, Philip H.
• Application Number:
  US09/155,399
• Time in Patent Office: 707 Days
• Field of Search: 219/728, 219/729, 219/730, 219/759, 99/DIG. 14, 426/107, 426/109, 426/241, 426/243, 426/234
• US Class Current: 219/728
• CPC Class Codes: B65D 2581/3441 3-D geometry or shape factors, e.g. depth-wise
• CPC Class Codes: B65D 2581/3468 Microwave reactive material directly applied on paper substrate
• CPC Class Codes: B65D 2581/3489 Microwave reflector, i.e. microwave shield B65D2581/3487 takes precedence
• CPC Class Codes: B65D 2581/3494 Microwave susceptor B65D2581/3487 takes precedence
• CPC Class Codes: B65D 81/3446 specially adapted to be heated by microwaves
• CPC Class Codes: Y10S 99/14 Induction heating

Abstract

A microwave energy heating element has a plurality of spaced microwave components generally arranged in a closed loop pattern. Each of the microwave components (42, 44) has a non-resonant length. When the heating element is in a loaded condition with a load juxtaposed thereto for capacitively coupling the microwave components together, the microwave components cooperatively redistribute impinging microwave energy. When the heating element is in an unloaded condition, the microwave components act independently remaining inert to impinging microwave energy.

Claims

1. A microwave energy heating element comprising a plurality of spaced microwave components generally arranged in a closed loop pattern, each of said microwave components having a non-resonant length, and when in a loaded condition with a load for capacitively coupling said microwave components together, said microwave components cooperatively redistribute impinging microwave energy, and when in an unloaded condition, said microwave components act independently remaining inert to impinging microwave energy.

2. A microwave energy heating element as claimed in claim 1 wherein said microwave components are arranged in an end to end relation.

3. A microwave energy heating element as claimed in claim 2 wherein said microwave components are identical to each other and are regularly spaced.

4. A microwave energy heating element as claimed in claim 3 wherein said microwave components each has a tab at one end and a slot at an opposite end, said tab sized to fit within a slot of an adjacent microwave component.

5. A microwave energy heating element as claimed in claim 3 wherein said microwave components are arranged in an inner loop pattern and an outer loop pattern concentric with said inner loop pattern.

6. A microwave energy heating element as claimed in claim 5 wherein said microwave components of said inner loop pattern are staggered relative to said microwave elements of said outer loop pattern.

7. A microwave energy heating element as claimed in claim 1 wherein said closed loop pattern has a circumferential length of one wavelength of said microwave energy.

8. A microwave energy heating element as claimed in claim 1 wherein said heating element is mounted on a substrate having at least one layer of susceptor material associated with one surface thereof.

9. A microwave energy heating element as claimed in claim 8 wherein said substrate is selected from the group consisting of polymeric film, paperboard and paper.

10. A microwave energy heating element as claimed in claim 9 wherein said microwave components are comprised of a metallic film.

11. A sandwich coupon comprising

a substrate;

a plurality of spaced microwave components generally arranged in a closed loop pattern on said substrate, each of said microwave components having a non-resonant length, and when in a loaded condition with a load for capacitively coupling said microwave components together, said microwave components cooperatively redistribute impinging microwave energy, and when in an unloaded condition, said microwave components act independently remaining inert to impinging microwave energy.

12. A sandwich coupon as claimed in claim 11 wherein said closed loop pattern has a circumferential length of one wavelength of said microwave energy.

13. A sandwich coupon as claimed in claim 11 wherein said substrate has at least one layer of susceptor material associated with one surface thereof.

14. A sandwich coupon as claimed in claim 13 wherein said substrate is selected from the group consisting of polymeric film, paperboard and paper.

15. A sandwich coupon as claimed in claim 14 wherein said microwave components are comprised of a metallic film.

16. A sandwich coupon as claimed in claim 13 wherein said substrate has a shield layer for protecting an outer edge of said load.

17. A sandwich coupon as claimed in claim 16 wherein said shield layer has an aperture having said plurality of spaced microwave components therein.

18. A sandwich coupon as claimed in claim 17 wherein said aperture is elongated and has said plurality of spaced microwave components arranged in a plurality of closed loop patterns.

19. A microwave energy heating element comprising a continuous portion having a non-resonant length and a discontinuous portion comprising a plurality of spaced microwave components, each of said microwave components having a non-resonant length, when said heating element is in a loaded condition with a load for capacitively coupling said continuous portion and said discontinuous portion together, said heating element cooperatively redistributes impinging microwave energy, and when in an unloaded condition, said continuous and discontinuous portions act independently remaining inert to impinging microwave energy.

20. A microwave energy heating element as claimed in claim 19 wherein said continuous portion includes a resonant loop section and transmission lines extending therefrom.

21. A microwave energy heating element as claimed in claim 20 wherein said discontinuous portion couples said transmission lines together to present a closed loop pattern.

22. A microwave energy heating element as claimed in claim 21 wherein said heating element is mounted on a substrate having at least one layer of susceptor material associated with one surface thereof.

23. A microwave energy heating element as claimed in claim 22 wherein said substrate is selected from the group consisting of polymeric film, paperboard and paper.

24. A microwave energy heating element as claimed in claim 23 wherein said microwave components are comprised of a metallic film.