MAGNETIC POSITIONING FOR INDUCTIVE COUPLING

• US 20090212637A1
• Filed: 02/20/2009
• Published: 08/27/2009
• Est. Priority Date: 02/22/2008
• Status: Active Grant

• Current Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Zylstra, Brad A., Baarman, David W., Norconk, Matthew J.
• Granted Patent: US 8,766,484 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01F 7/021 Construction of PM H01F7/0278 takes precedence; PM compositions H01F1/032
• CPC Class Codes: H01F 7/0247 Orientating, locating, transporting arrangements
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction
• CPC Class Codes: H04B 5/00 Near-field transmission systems, e.g. inductive or capacitive transmission systems
• CPC Class Codes: H04B 5/0037 for power transfer
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A magnetic positioning system for use in inductive couplings. The magnetic positioning system having a magnet that provides sufficient magnetic force, but does not have enough electrical conductivity to overheat in the presence of the anticipated electromagnetic field. The magnet may be a bonded magnet or a shielded magnet. In another aspect a plurality of magnets are used to provide magnetic attraction forces and said magnetic repulsion forces that cooperate to align the inductive power supply and the remote device. In another aspect, a sensor allows differentiation between different positions of the remote device or inductive power supply. In another aspect, multiple magnets in the inductive power supply interact with multiple magnets in the remote device to position the remote device in different positions.

Claims

1. A magnetic positioning system for use in an inductive power supply system for wirelessly transferring power from an inductive power supply to a remote device using an electromagnetic field, said magnetic positioning system comprising:

a bonded magnet located in the electromagnetic field and said bonded magnet located in at least one of the inductive power supply and the remote device;

wherein said bonded magnet provides magnetic force for alignment of the inductive power supply and the remote device; and

wherein said bonded magnet limits heat generated in said bonded magnet by the electromagnetic field.

2. The magnetic positioning system of claim 1 further comprising an additional magnet located in at least one of the inductive power supply and the remote device, said additional magnet location being different from said bonded magnet location.

3. The magnetic positioning system of claim 1 further comprising a ferrous element located in at least one of the inductive power supply and the remote device, said ferrous element location being different from said bonded magnet location.

4. The magnetic positioning system of claim 1 wherein said bonded magnet includes at least one of bonded neodymium and bonded samarium cobalt.

5. The magnetic positioning system of claim 1 wherein said bonded magnet is bound together by a binder.

6. The magnetic positioning system of claim 5 wherein said binder is electrically non-conductive.

7. The magnetic positioning system of claim 1 wherein said bonded magnet includes particles of a rare earth magnet.

8. The magnetic positioning system of claim 7 wherein said rare earth magnet is a ceramic ferrite magnet.

9. A magnetic positioning system for use in an inductive power supply system for wirelessly transferring power from an inductive power supply to a remote device using an electromagnetic field, said magnetic positioning system comprising:

a first magnet located in at least one of said inductive power supply and said remote device, wherein said first magnet provides a magnetic force for alignment of the inductive power supply and the remote device; and

a shield configured to reduce the electromagnetic field that reaches said first magnet during wireless power transfer from the inductive power supply to the remote device.

10. The magnetic positioning system of claim 9 further comprising a second magnet located in proximity to said first magnet, wherein said second magnet provides additional magnetic force for alignment of the inductive power supply and the remote device.

11. The magnetic positioning system of claim 10 wherein said first magnet and said second magnet sandwich said shield.

12. The magnetic positioning system of claim 9 wherein said shield defines a hole, wherein said first magnet is disposed within said hole of said shield.

13. The magnetic positioning system of claim 9 wherein said shield defines a sleeve, wherein said first magnet is disposed within said sleeve of said shield.

14. The magnetic positioning system of claim 9 wherein said shield defines a cavity, wherein said first magnet is disposed within said cavity of said shield.

15. The magnetic positioning system of claim 9 wherein said first magnet is flush with a charging surface of the inductive power supply.

16. The magnetic positioning system of claim 9 wherein said shield is flush with a charging surface of the inductive power supply.

17. The magnetic positioning system of claim 9 wherein said at least one of said inductive power supply and said remote device is rotatable with respect to said first magnet and wherein at least one of said inductive power supply and said remote device at least one of receives and transmits power during said rotation.

18. A magnetic positioning system for use in an inductive power supply system for wirelessly transferring power from an inductive power supply to a remote device using an electromagnetic field, said magnetic positioning system comprising:

at least one of the inductive power supply and the remote device including;

a first magnet having a first polarity;

a second magnet having a second polarity opposite from said first polarity of said first magnet;

the other one of the inductive power supply and the remote device including;

a third magnet having a third polarity opposite from said first polarity of said first magnet;

wherein said first magnet and said third magnet provide a magnetic attraction force; and

wherein said second magnet and said third magnet provide a magnetic repulsion force; and

wherein said magnetic attraction force and said magnetic repulsion force cooperate to align the inductive power supply and the remote device.

19. The magnetic positioning system of claim 18 further comprising a fourth magnet that provides at least one of an additional magnetic attraction force and an additional magnetic repulsion force for aligning the inductive power supply and the remote device.

20. The magnetic positioning system of claim 18 wherein said magnetic attraction force and said magnetic repulsion force provide tactile user feedback on a blind surface to allow a user to align the remote device and the inductive power supply for charging.

21. A magnetic positioning system for use in an inductive power supply system for wirelessly transferring power from an inductive power supply to a remote device using an electromagnetic field, said magnetic positioning system comprising:

at least one of the inductive power supply and the remote device including a plurality of magnets;

the other one of the inductive power supply and the remote device including an additional magnet;

wherein said plurality of magnets and said additional magnet provide a magnetic force for alignment of the inductive power supply and the remote device into a plurality of different positions;

a sensor located in at least one of the inductive power supply and the remote device, wherein said sensor is configured to provide sensor output to differentiate between said plurality of different positions;

a controller located in at least one of the inductive power supply and the remote device, wherein said controller is in communication with said sensor, said controller programmed to generate an input as a function of said sensor output.

22. The magnetic positioning system of claim 21 wherein said controller is programmed to determine whether to operate a display on the remote device in at least one of portrait and landscape mode as a function of said sensor output.

23. The magnetic positioning system of claim 21 wherein said controller is programmed to determine an orientation of the remote device with respect to the inductive power supply as a function of said sensor output.

24. The magnetic positioning system of claim 21 wherein said controller is programmed to determine a direction of rotation of the remote device as a function of said sensor output.

25. The magnetic positioning system of claim 21 wherein said input is at least one of a volume control input and a brightness control input for the remote device.

26. The magnetic positioning system of claim 21 further comprising an index magnet, located in at least one of the inductive power supply and the remote device, wherein said index magnet provides a reference to assist in differentiating between said plurality of different positions.

27. The magnetic positioning system of claim 21 wherein said sensor includes a hall effect sensor.

28. A magnetic positioning system for use in an inductive power supply system for wirelessly transferring power from an inductive power supply to a remote device using an electromagnetic field, said magnetic positioning system comprising:

at least one of the inductive power supply and the remote device including a first plurality of magnets;

the other one of the inductive power supply and the remote device including a second plurality of magnets;

wherein said first plurality of magnets and said second plurality of magnets provide a magnetic force for alignment of the inductive power supply and the remote device into a plurality of different positions.