WIRELESS CHARGER DECREASED IN VARIATION OF CHARGING EFFICIENCY

• US 20090102419A1
• Filed: 05/04/2006
• Published: 04/23/2009
• Est. Priority Date: 07/27/2005
• Status: Abandoned Application

• Current Assignee: LS Cable Limited (LS Corporation)
• Original Assignee: LS Cable Limited (LS Corporation)
• Inventors: Choi, Sung-Wook, Han, Sub, Gwon, Gwang-Hee, Park, Dong-Young, Moon, Sung-Wook
• Application Number:
  US11/996,621
• Publication Number:
  US 20090102419A1
• Time in Patent Office: Days
• US Class Current: 320/108
• 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 50/10 using inductive coupling
• 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 50/70 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

Abstract

A wireless charger charges a storage battery of a portable electronic device in a wireless manner (non-contacting or contact-less) so that a variation of charging efficiency is not serious though the storage battery is placed any position of the wireless charger. The wireless charger is provided with a primary coil for generating a magnetic field so as to charge a subject, which is provided with a secondary coil, by means of inductive coupling with the secondary coil. The primary coil includes an outer coil arranged with a predetermined winding number and a predetermined size; and at least one inner coil arranged to be included inside the outer coil. The outer coil and the inner coil are arranged so that, when a primary current is applied to the outer coil and the inner coil, magnetic fluxes generated in the outer coil and the inner coil are formed in the same direction.

Claims

1. A wireless charger provided with a primary coil for generating a magnetic field so as to charge a subject, which is provided with a secondary coil, by means of inductive coupling with the secondary coil, wherein the primary coil includes:

an outer coil arranged with a predetermined winding number and a predetermined size; and

at least one inner coil arranged to be included inside the outer coil,

wherein the outer coil and the inner coil are arranged so that, when a primary current is applied to the outer coil and the inner coil, magnetic fluxes generated in the outer coil and the inner coil are formed in the same direction.

2. The wireless charger according to claim 1,

wherein centers of the outer coil and the inner coil are identical.

3. The wireless charger according to claim 1,

wherein there are provided at least two inner coils, and the at least two inner coils are subsequently arranged one in another.

4. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and/or the inner coil are wound into a shape of a substantially planar circle.

5. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and/or the inner coil are wound into a shape of a substantially planar polygon.

6. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and/or the inner coil are configured by winding at least one conductive wire made of a material selected from the group consisting of gold, silver, copper and aluminum.

7. The wireless charger according to claim 6,

wherein the outer coil and/or the inner coil are composed of Litz wire.

8. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and/or the inner coil are configured with a conductor pattern formed by patterning on a substrate film.

9. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and the inner coil are connected in series with each other.

10. The wireless charger according to any of claims 1 to 3,

wherein the outer coil and the inner coil are indirectly connected with each other.

11. The wireless charger according to any of claims 1 to 3,

wherein a density profile of magnetic flux formed when a primary current is applied to the primary coil has at least three local maximum points inside the primary coil, seen along a traversing line of the primary coil.

12. The wireless charger according to any of claims 1 to 3,

wherein the inner coil is arranged between the outer coil and a point at which a density of magnetic flux formed by the outer coil when a primary current is applied only to the outer coil is 50% of its maximum value.

13. A wireless charger provided with a primary coil for generating a magnetic field so as to charge a subject, which is provided with a secondary coil, by means of inductive coupling with the secondary coil,

wherein the primary coil is arranged with a predetermined winding number and a predetermined size, and

wherein a density profile of magnetic flux formed when a primary current is applied to the primary coil has at least three local maximum points inside the primary coil, seen along a traversing line of the primary coil.

14. The wireless charger according to claim 13,

wherein, in the magnetic flux density profile inside the primary coil, a minimum value of a magnetic flux density is at least 50% of a maximum value of the magnetic flux density.

15. The wireless charger according to claim 13, wherein the primary coil includes:

an outer coil arranged with a predetermined winding number and a predetermined size; and

at least one inner coil arranged to be included inside the outer coil,

wherein the outer coil and the inner coil are arranged so that, when a primary current is applied to the outer coil and the inner coil, magnetic fluxes generated in the outer coil and the inner coil are formed in the same direction.

16. A wireless charger provided with a primary coil for generating a magnetic field so as to charge a subject, which is provided with a secondary coil, by means of inductive coupling with the secondary coil,

wherein the primary coil is arranged with a predetermined winding number and a predetermined size, and

wherein a density of magnetic flux formed when a primary current is applied to the primary coil is at least 50% of a maximum value of the magnetic flux density at any point inside the primary coil.

17. The wireless charger according to claim 16,

wherein a magnetic flux density formed when a primary current is applied to the primary coil is at least 70% of a maximum value of the magnetic flux density at any point inside the primary coil.

18. The wireless charger according to claim 16,

wherein a profile of the magnetic flux density, seen along a traversing line of the primary coil, has at least three local maximum points inside the primary coil.

19. The wireless charger according to claim 16, wherein the primary coil includes:

an outer coil arranged with a predetermined winding number and a predetermined size; and

at least one inner coil arranged to be included inside the outer coil,

wherein the outer coil and the inner coil are arranged so that, when a primary current is applied to the outer coil and the inner coil, magnetic fluxes generated in the outer coil and the inner coil are formed in the same direction.