ANTENNA COIL

• US 20150137612A1
• Filed: 05/14/2013
• Published: 05/21/2015
• Est. Priority Date: 05/17/2012
• Status: Active Grant

• Current Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Original Assignee: Equos Research Co., Ltd. (Aisin Corp.)
• Inventors: Yamakawa, Hiroyuki, Satou, Kenichirou
• Granted Patent: US 9,318,258 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 7/08 Ferrite rod or like elongated core
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

Provided is an antenna coil capable of forming a magnetic field in a desired direction in an efficient manner, while suppressing leakage of magnetic flux into a space other than the space in which the magnetic field is formed. The antenna coil includes a main coil portion formed by winding a length of conductor wire around a first reference axis and an auxiliary coil portion formed by winding the conductor wire around a second reference axis. The second reference axis is set to intersect the magnetic flux of the main coil portion at an axial end of the auxiliary coil portion. The main coil portion and the auxiliary coil portion are connected to together form a closed circuit.

Claims

1. An antenna coil comprising a main coil portion formed by winding a length of conductor wire around a first reference axis and an auxiliary coil portion formed by winding a length of conductor wire around a second reference axis;

wherein the second reference axis is set to intersect the magnetic flux of the main coil portion at an axial end of the auxiliary coil portion; and

the main coil portion and the auxiliary coil portion together form a closed circuit.

2. The antenna coil according to claim 1, wherein vector of the magnetic flux of the main coil portion at the axial end of the auxiliary coil portion is deflected in the direction along the second reference axis, relative to vector of the magnetic flux of the main coil portion at a virtual end set opposite to the axial end across the main coil portion.

3. The antenna coil according to claim 1, wherein the sum of inductance(s) of one or more auxiliary coil portions is set smaller than the sum of inductance(s) of one or more main coil portion(s).

4. The antenna coil according to claim 1, wherein the auxiliary coil portion is formed by winding a length of conductor wire around an auxiliary coil core formed of magnetic material and disposed along the second reference axis.

5. The antenna coil according to claim 1, wherein the auxiliary coil portion is disposed such that of components of a current flowing in the auxiliary coil portion, a component parallel with the circumferential direction of the main coil portion has a same direction as a current flowing in the main coil portion on the side proximate to this main coil portion.

6. The antenna coil according to claim 1, wherein at least one auxiliary coil portion is disposed along one axial end face of the main coil portion and has a smaller diameter than the main coil portion.

7. The antenna coil according to claim 6, wherein the antenna coil is provided in at least one of a power supplying circuit and a power receiving circuit of a magnetic resonance power supplying apparatus for effecting wireless power supply, and the auxiliary coil portion is disposed along a back face side axial end face which is the axial end face opposite to the side opposed to the other antenna coil.

8. The antenna coil according to claim 1, wherein a plurality of the auxiliary coil portions are disposed equidistantly along the circumferential direction of the main coil portion.

9. The antenna coil according to claim 1, wherein the auxiliary coil portion is disposed in such a manner as to have a portion thereof overlapped with the main coil portion as seen along the axial direction of the first reference axis.

10. The antenna coil according to claim 1, wherein the main coil portion is formed like a coil along a reference plane perpendicular to the first reference axis.