FLUX CONCENTRATOR AND METHOD OF MAKING A MAGNETIC FLUX CONCENTRATOR

• US 20110050382A1
• Filed: 08/25/2010
• Published: 03/03/2011
• Est. Priority Date: 08/25/2009
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Turner, Kaitlyn J., Taylor, Roy M. JR., Berwald, Thomas J., Miles, Michael E., Baarman, David W., Norconk, Matthew J., Schwannecke, Joshua K., Stoner, William T. JR.
• Granted Patent: US 8,692,639 B2
• Time in Patent Office: Days
• US Class Current: 336/221
• CPC Class Codes: H01F 1/26 by macromolecular organic substances
• CPC Class Codes: H01F 1/375 Flexible bodies
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/327 Encapsulating or impregnating encapsulating coil and core H01F27/022
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10

Abstract

A flux concentrator and method for manufacturing a flux concentrator is provided. The method can include combining powdered soft magnetic material, a binder, a solvent, a internal lubricant; mixing the materials to create a mixture, evaporating the solvent from the mixture, molding the mixture to form a flux concentrator, and curing the flux concentrator. The flux concentrator may be laminated and broken into multiple pieces, which makes the flux concentrator more flexible. Breaking the flux concentrator does not significantly affect the magnetic properties. Since the permeability of the binder is very similar to that of air, adding tiny air gaps between the fractions is not significantly different than adding more binder.

Claims

1. A flux concentrator assembly comprising:

a flux concentrator having a thickness, a top surface, and a bottom surface; and

a coil embedded in said flux concentrator, wherein one side of said coil is flush with said top surface of said flux concentrator forming an exposed side and another side of said coil is embedded within said thickness of said compression molded flux concentrator forming an unexposed side, wherein said coil is capable of inductive coupling on said exposed side and is incapable of inductive coupling on said unexposed side.

2. The flux concentrator assembly of claim 1 wherein said coil is selected from said group comprising a primary coil for transferring wireless power and a secondary coil for receiving wireless power.

3. The flux concentrator assembly of claim 1 wherein said compression molded flux concentrator concentrates electromagnetic field to increase inductive coupling.

4. The flux concentrator assembly of claim 1 wherein said coil is at least one of a stamped coil and a wire coil.

5. The flux concentrator assembly of claim 1 further including a magnet or magnetic attractor capable of providing sufficient magnetic attraction for alignment of a remote device with a wireless power transfer system.

6. The flux concentrator assembly of claim 5 wherein said magnet or magnetic attractor is either exposed on said flux concentrator surface or embedded below said surface of said flux concentrator.

7. The flux concentrator assembly of claim 1 further including a permanent magnet, wherein said flux concentrator assembly includes an insulator between said magnet and said flux concentrator for minimizing effects of AC field saturation caused by said permanent magnet.

8. The flux concentrator assembly of claim 1 further including a layer of strengthening material laminated on said top surface of said flux concentrator.

9. The flux concentrator assembly of claim 1 further including a layer of material laminated on said bottom surface of said flux concentrator, wherein said flux concentrator is breakable into a plurality of pieces with air gaps therebetween.

10. The flux concentrator assembly of claim 9 wherein said air gaps do not significantly affect the properties of said flux concentrator.

11. A flexible flux concentrator assembly comprising:

a flux concentrator having a thickness and a surface;

a laminate adhesively secured to at least a portion of said surface of said flux concentrator;

wherein in response to bending said flexible flux concentrator

     1) said flux concentrator is capable of being broken into a plurality of pieces with air gaps therebetween; and

     2) said laminate remain adhesively secured to said at least said portion of said surface of said flux concentrator.

12. The flexible flux concentrator of claim 11 wherein said laminate surrounds said flux concentrator.

13. The flexible flux concentrator of claim 11 wherein breaking said flux concentrator does not significantly affect the properties of said flux concentrator.

14. The flexible flux concentrator of claim 11 wherein said flux concentrator is scored to influence where said flux concentrator breaks in response to bending.

15. The flexible flux concentrator assembly of claim 11 including:

a coil embedded in said flux concentrator, wherein one side of said coil is flush with said surface of said flux concentrator forming an exposed side and another side of said coil is embedded within said thickness of said compression molded flux concentrator forming an unexposed side, wherein said coil is capable of inductive coupling on said exposed side and is incapable of inductive coupling on said unexposed side.

16. The flexible flux concentrator assembly of claim 11 further including a magnet or magnetic attractor capable of providing sufficient magnetic attraction for alignment of a remote device with a wireless power transfer system.

17. A flux concentrator comprising:

a soft magnetic material molded into a shape with a width dimension, a thickness dimension, and a height dimension;

at least one of said height dimension and said width dimension is 25 times or greater than said thickness dimension; and

wherein said flux concentrator has a saturation 500 mT or greater.

18. The flux concentrator of claim 17, said flux concentrator having permeability greater than 15 times permeability of free space.

19. The flux concentrator of claim 17, said flux concentrator having conductivity of 1 S/m or less.

20. The flux concentrator of claim 17, said thickness dimension is 1 mm or less.

21. A wireless power module comprising:

a flux concentrator having a thickness and a surface;

a first coil embedded in said flux concentrator, one side of said first coil is flush with said surface of said flux concentrator forming an exposed side and another side of said first coil is embedded within said thickness of said flux concentrator forming an unexposed side, wherein said first coil is capable of inductive coupling on said exposed side and is incapable of inductive coupling on said unexposed side; and

wireless power circuitry surface mounted to said flux concentrator surface, wherein said coil is electrically connected to said wireless power circuitry through traces embedded in said flux concentrator, wherein said wireless power circuitry is electrically connected to a wireless power module output through traces embedded in said flux concentrator.

22. The wireless power module of claim 21 including a second coil embedded in said flux concentrator, one side of said second coil is flush with said surface of said flux concentrator and another side of said second coil is embedded within said thickness of said flux concentrator, wherein said second coil is capable of inductive coupling on said exposed side and is incapable of inductive coupling on said unexposed side.

23. The wireless power module of claim 21 wherein said first coil and said second coil are part of a single layer coil array assembly.

24. The wireless power module of claim 21 including a multi-layer coil array assembly, wherein said first coil and one or more additional coils are positioned to form a multi-layer coil array in the wireless power module, the multi-layer coil array assembly including a non-conductive material between said one or more additional coils and said surface of said flux concentrator.