Electric power feed apparatus, electric power feed system, and electronic apparatus

• US 10,685,780 B2
• Filed: 03/09/2012
• Issued: 06/16/2020
• Est. Priority Date: 03/29/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Miyamoto, Takashi
• Primary Examiner(s): Sun, Pinping
• Assistant Examiner(s): Vu, Toan T
• Application Number:
  US14/005,776
• Publication Number:
  US 20140008974A1
• Time in Patent Office: 3,021 Days
• Field of Search: 307104
• CPC Class Codes: H01F 27/2871 Pancake coils
• 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 50/12 of the resonant type
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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

Abstract

There are provided an electric power feed apparatus, an electric power feed system, and an electronic apparatus which are capable of performing transmission efficiency control corresponding to positions of apparatuses when electric power transmission is performed between the apparatuses through a magnetic field. The electric power feed apparatus includes an electric power transmission section including an electric power transmission coil for performing electric power transmission through a magnetic field and an auxiliary resonance section including one or a plurality of resonators. A main resonant frequency in a main resonance operation with use of the electric power transmission coil during the electric power transmission and an auxiliary resonant frequency in the resonator are different from each other. A relationship (corresponding characteristics) between a relative position between the electric power feed apparatus (an electric power transmission side) and the electronic apparatus (an electric power reception side) and transmission efficiency during electric power transmission is varied by adjustment of such a difference between the resonant frequencies.

Claims

1. An electric power feed apparatus, comprising:

an electric power transmission section including;

a main resonance section that comprises an electric power transmission coil and a first resonant capacitor, wherein the main resonance section is configured to transmit electric power to an electronic apparatus through a magnetic field; and

an auxiliary resonance section including at least one resonator, wherein the auxiliary resonance section is configured to;

control a resonance operation of the main resonance section at a time of the transmission of the electric power; and

control, based on adjustment of a difference between a main resonant frequency of the main resonance section and an auxiliary resonant frequency of the at least one resonator, position characteristics that indicate a relationship between transmission efficiency of the electric power feed apparatus and a relative position between the electric power feed apparatus and the electronic apparatus, wherein

the at least one resonator comprises an auxiliary coil and a second resonant capacitor, and

the transmission efficiency is associated with the transmission of the electric power by the main resonance section.

2. The electric power feed apparatus according to claim 1, wherein an internal diameter of the auxiliary coil is smaller than an internal diameter of the electric power transmission coil.

3. The electric power feed apparatus according to claim 1, wherein a central point of the electric power transmission coil and a central point of the auxiliary coil are located along a same axis.

4. The electric power feed apparatus according to claim 1, wherein the electric power transmission coil and the auxiliary coil are on a same plane.

5. The electric power feed apparatus according to claim 1, wherein the auxiliary resonance section includes a plurality of resonators each including an auxiliary coil.

6. The electric power feed apparatus according to claim 5, wherein an internal diameter of each of the auxiliary coils in the plurality of resonators is smaller than an internal diameter of the electric power transmission coil, and the internal diameters of the auxiliary coils are different from one another.

7. The electric power feed apparatus according to claim 6, wherein a central point of the electric power transmission coil and a central point of each of the auxiliary coils are located along a substantially same axis.

8. The electric power feed apparatus according to claim 7, wherein a difference value between internal diameters of the electric power transmission coil and an outermost auxiliary coil and a difference value between internal diameters of adjacent auxiliary coils are gradually increased from the electric power transmission coil side toward the central point.

9. The electric power feed apparatus according to claim 7, wherein each of the electric power transmission coil and the auxiliary coils has an inner surface shape exhibiting anisotropy, and a difference value between internal diameters of the electric power transmission coil and an outermost auxiliary coil and a difference value between internal diameters of adjacent auxiliary coils are larger in a major-axis direction in the inner surface shape than in a minor-axis direction.

10. The electric power feed apparatus according to claim 5, wherein the electric power transmission coil and each of the auxiliary coils in the plurality of resonators are disposed on a substantially same plane.

11. The electric power feed apparatus according to claim 5, wherein auxiliary resonant frequencies in the plurality of resonators are different from one another.

12. The electric power feed apparatus according to claim 1, wherein the electric power transmission coil is electrically insulated from the auxiliary coil.

13. The electric power feed apparatus according to claim 1, further comprising one of a capacitor element or a parasitic capacitance component for the resonance operation.

14. The electric power feed apparatus according to claim 1, wherein the first resonant capacitor of the main resonance section has a variable capacitance value and the second resonant capacitor of the auxiliary resonance section has a fixed capacitance value.

15. The electric power feed apparatus according to claim 1, further comprising a switch configured to adjust a capacitance value of at least one of the first resonant capacitor or the second resonant capacitor based on a switching operation between connection paths of a plurality of capacitor elements of the electric power feed apparatus.