RESONATOR STRUCTURES AND METHOD OF MAKING

• US 20120306280A1
• Filed: 05/31/2011
• Published: 12/06/2012
• Est. Priority Date: 05/31/2011
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Krishna, Kalaga Murali, Reddy, Sudhakar Eddula, Matani, Lohit
• Granted Patent: US 9,027,236 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H01P 11/008 Manufacturing resonators
• CPC Class Codes: H01P 7/00 Resonators of the waveguide type
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A resonator in the Swiss-roll structure, method of making the resonator structure and the system employing the resonator are disclosed. The resonator includes a plurality of layers, including a ceramic layer and a metallic layer. The ceramic and metallic layers are configured in a Swiss-roll form such that the neighboring ceramic layers are separated by the metallic layer. Further, the ceramic layer includes materials that have a dielectric constant of at least about 10 and dielectric loss tangent less than about 0.01 in the frequency range of about 1 KHz to about 100 MHz. The method of forming the resonator includes the steps of disposing a metallic layer, depositing a dielectric ceramic layer, and forming a Swiss-roll structure of the metallic and ceramic layers. Alternate method includes swaging the dielectric material filled metal tubes and forming into Swiss-rolls. Further steps include heat treating the resultant Swiss-roll structure in vacuum, inert atmosphere, or reducing atmosphere to form a monolithic Swiss-roll structure, such that the air gap between turns of the Swiss-roll structure is less than about 1 μm.

Claims

1. A resonator, comprising:

a plurality of layers, comprising a ceramic layer and a metallic layer, configured in a Swiss-roll form, wherein the neighboring ceramic layers are separated by the metallic layer, and the ceramic layer comprises materials having a dielectric constant of at least about 10 and dielectric loss tangent less than about 0.01 in the frequency range of about 1 KHz to about 100 MHz.

2. The resonator of claim 1, wherein the ceramic layer is disposed over the metallic layer.

3. The resonator of claim 1, wherein the ceramic layer has a thickness in the range from about 0.01 mm to about 10 mm.

4. The resonator of claim 1, wherein the metallic layer has a thickness in the range from about 0.1 mm to 10 mm.

5. The resonator of claim 1, wherein the ceramic layer comprises a material with a melting point less than about 1500°

C.

6. The resonator of claim 1, wherein the ceramic layer comprises an alkaline-earth titanate.

7. The resonator of claim 1, wherein the ceramic layer has a discrete porosity less than about 10 volume percent.

8. The resonator of claim 1, wherein the metallic layer comprises copper, silver, alluminium, iron, gold, nickel, palladium, indium, gallium, zinc, lead, tin, platinum or any combination thereof.

9. The resonator of claim 1, where in the Swiss-roll comprises turns in a range from about 2 to about 100.

10. The resonator of claim 9, wherein an air gap between the turns is less than about 1 μ

m.

11. The resonator of claim 1, wherein an inner diameter of the Swiss-roll form is in a range from about 5 mm to about 100 cm.

12. The resonator of claim 1, wherein an outer diameter of the Swiss-roll form is in a range from about 5 mm to about 300 cm.

13. A method of forming a resonator, comprising:

disposing a metallic layer;

depositing a dielectric ceramic layer;

forming a Swiss-roll structure of metallic layer and ceramic layer; and

heat treating the Swiss-roll structure in vacuum, inert atmosphere, or reducing atmosphere to form a monolithic Swiss-roll structure, wherein an air gap between the turns of Swiss-roll structure is less than about 1 μ

m.

14. The method of claim 13, wherein the metallic layer is prepared by disposing metallic powders.

15. The method of claim 13, further comprising a step of providing a buffer layer over a metallic layer before providing the ceramic dielectric layer.

16. The method of claim 15, wherein the metallic layer, buffer layer, and ceramic layer are heat-treated to obtain an integrated monolithic structure of density greater than 98% by volume.

17. The method of claim 16, wherein the temperature of heat treatment is less than the melting point of materials of the metallic layer.

18. A method of forming a resonator, comprising:

disposing a metallic hollow tube;

filling-in the metallic hollow tube with a dielectric ceramic material to form a filled metallic tube;

swaging or rolling of the filled metallic tube to form a layered structure comprising a ceramic layer in between two metallic layers;

winding the layered structure to form a Swiss-roll structure of metallic layer and ceramic layer; and

heat treating the Swiss-roll structure in vacuum, inert atmosphere, or reducing atmosphere to form a monolithic Swiss-roll structure, wherein an air gap between the turns of Swiss-roll structure is less than about 1 μ

m.

19. The method of claim 18, further comprising machining or chemically etching outer edges of the Swiss-roll structure to expose the ceramic and metallic layers.

20. A power transfer system comprising:

a first coil coupled to a power source;

a second coil coupled to a load; and

a field-focusing element disposed between the first coil and the second coil and comprising a dielectric resonator, wherein the dielectric resonator comprises a plurality of layers, comprising a ceramic layer and a metallic layer, configured in a Swiss-roll form, wherein the neighboring ceramic layers are separated by the metallic layer, and ceramic layer comprises materials having a dielectric constant of at least about 10 and dielectric loss tangent less than about 0.01 in the frequency range of about 1 KHz to about 100 MHz.