Wireless power utilization in a local computing environment

• US 8,598,747 B2
• Filed: 11/18/2011
• Issued: 12/03/2013
• Est. Priority Date: 11/23/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Bilbrey, Brett C., Culbert, Michael, Arnold, Peter M., Simon, David I., Sarwar, Mushtaq, DeVaul, Richard W.
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): PARRIES, DRU M
• Application Number:
  US13/989,047
• Publication Number:
  US 20130241308A1
• Time in Patent Office: 746 Days
• Field of Search: 307/104
• US Class Current: 307/104
• CPC Class Codes: G01R 33/3692 involving signal transmission without using electrically conductive connections, e.g. wireless communication or optical communication of the MR signal or an auxiliary signal other than the MR signal
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Various embodiments of a wirelessly powered local computing environment are described. The wireless powered local computing environment includes at least a near field magnetic resonance (NFMR) power supply arranged to wirelessly provide power to any of a number of suitably configured devices. In the described embodiments, the devices arranged to receive power wirelessly from the NFMR power supply must be located in a region known as the near field that extends no further than a distance D of a few times a characteristic size of the NFMR power supply transmission device. Typically, the distance D can be on the order of 1 meter or so.

Claims

1. A near field magnetic resonance (NFMR) power supply arranged to use a resonance channel to transfer energy to resonance circuits within a near field distance D, the distance D defining an outermost range of the NFMR power supply, comprising:

a high frequency (HF) power source for providing a high frequency, orthogonal in-band power;

a base plate that provides high frequency (HF) power coupled to the HF power source; and

at least two “

D”

shaped resonators arranged to receive HF power from the base plate, wherein the least two D shaped resonators are driven 180°

out of phase with each other, wherein the magnetic fields produced by the at least two D shaped resonators are arranged to provide a symmetric magnetic field at a resonant frequency.

2. The NFMR power supply as recited in claim 1, wherein the symmetric magnetic field is circularly polarized.

3. The NFMR power supply as recited in claim 1, wherein power is wirelessly transferred from the NFMR power supply to a peripheral device in resonance with the circularly polarized magnetic field at the resonant frequency.

4. The NFMR power supply as recited in claim 3, the peripheral device comprising:

a base arranged to enclose and support at least operating components and a battery, and

and a resonator structure electrically coupled to the battery having a size and shape in accordance with the at least two D shaped resonators.

5. The NFMR power supply as recited in claim 4, further comprising:

a central processing unit arranged to provide processing resources to the NFMR power supply; and

a housing, at least a portion of the housing being formed of metal and used as a re-resonator arranged to re-resonate the circularly polarized magnetic field from the D shaped resonators to the peripheral device wherein the portion of the housing used as the re-resonator is configurable to adjust the resonant frequency.

6. The NFMR power supply as recited in claim 5, the peripheral device further comprising:

a processor;

a dynamically tunable resonance circuit in communication with the processor suitably adapted to receive power wirelessly from the NFMR power supply, wherein the processor directs the resonance circuit to tune at least one of the resonance frequencies of the NFMR power supply.

7. The NFMR power supply as recited in claim 6, where the peripheral device provides an identification to the NFMR power by the processor directing the tunable resonance circuit to subsequently de-tune thereby altering a resonance circuit load factor.

8. The NFMR power supply as recited in claim 7, wherein the change in resonance circuit load factor is detected by the NFMR power supply and is used by the NFMR power supply processor to provide a device identification of the de-tuned peripheral device.

9. The NFMR power supply as recited in claim 8, wherein the NFMR power is dynamically tuned by changing a shape of at least one of the D shaped resonators.

10. The NFMR power supply as recited in claim 9, wherein the shape of the at least one of the D shaped resonators is carried out using a piezoelectric shaping mechanism.

11. The NFRM power supply as recited in claim 10, wherein the resonant frequency of the NFMR power supply is dynamically tuned by varying a center resonance frequency to compensate for parasitic capacitance.

12. The NFMR power supply as in claim 1 wherein the at least two “

D”

shaped resonators are arranged to provide an elliptically polarized magnetic field.

13. The NFMR power supply as in claim 12 wherein the at least two “

D”

shaped resonators are configured to modify the orientation of the axes of the magnetic fields produced by the at least two “

D”

resonators.

14. The NFMR power supply as in claim 1 further comprising

a transmit circuit to generate a near field energy;

an antenna to transmit the near field energy; and

an impedance matching circuit to match an impedance of the transmit circuit to an impedance of the antenna.

15. The NFMR power supply as in claim 14 further comprising a low pass filter to reduce a harmonic emission from the antenna.

16. The NFMR power supply as in claim 1 further comprising a ground comb in proximity to the at least two “

D”

shaped resonators to preferentially block a magnetic flux.

17. The NFMR power supply as in claim 16 wherein the ground comb further comprises:

a first plurality of magnetically active elements, and

a second plurality of magnetically active elements arranged in relation to the first plurality of magnetically active elements to form at least one aperture, wherein the first and second plurality of magnetically active elements permit transmission of an incident magnetic field through the ground comb only at the apertures.

18. The NFMR power supply as in claim 3 wherein the peripheral device comprises a magnetic flux concentrator arranged to increase a local magnetic flux of the symmetric magnetic field.

19. The NFMR power supply as in claim 1 wherein the HF power source is arranged to modify an effective range of the NFMR by adjusting the orthogonal in-band power.

20. The NFMR power supply as in claim 3 wherein the peripheral device is one of a group of peripheral devices at least one of which is a keyboard and at least another is a mouse.

21. The NFMR power supply as recited in claim 20, wherein at least one of the peripheral devices includes a re-resonator circuit, the re-resonator circuit arranged to wirelessly provide a portion of the power received by the peripheral device from the NFMR power supply to the another peripheral device.