Power feeding coil unit and wireless power transmission device

• US 9,716,390 B2
• Filed: 11/20/2014
• Issued: 07/25/2017
• Est. Priority Date: 11/28/2013
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: Chiyo, Noritaka, Nishiyama, Tetsuya
• Primary Examiner(s): NGUYEN, TUYEN T
• Application Number:
  US14/548,950
• Publication Number:
  US 20150145341A1
• Time in Patent Office: 978 Days
• Field of Search: 336 65, 336200, 336232, 336170, 336173, 336214-215
• CPC Class Codes: H01F 27/24 Magnetic cores
• CPC Class Codes: H01F 27/38 Auxiliary core members; Auxiliary coils or windings
• CPC Class Codes: H01F 3/10 Composite arrangements of magnetic circuits
• 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 50/10 using inductive coupling
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields

Abstract

A power feeding coil unit includes a power feeding coil, and first and second auxiliary coils arranged so that a wire of the first auxiliary coil and a wire of the second auxiliary coil do not overlap a wire of the a power feeding coil when viewed from a direction perpendicular to an axial direction of the power feeding coil. A direction of circulation of a magnetic flux generated by the first auxiliary coil and a magnetic flux generated by the second auxiliary coil are opposite to a direction of circulation of a magnetic flux generated by the power feeding coil. An axes of the first and second auxiliary coils are substantially perpendicular to a power feeding direction of the power feeding coil, and are not aligned with the axis of the power feeding coil.

Claims

1. A power feeding coil unit for wirelessly feeding power, comprising:

a power feeding coil having a wire wound in a helical shape; and

a first auxiliary coil and a second auxiliary coil, each of the first auxiliary coil and the second auxiliary coil having a wire wound in a helical shape, wherein

the first auxiliary coil and the second auxiliary coil are arranged so that the wire of the first auxiliary coil and the wire of the second auxiliary coil do not overlap the wire of the power feeding coil when viewed from a direction perpendicular to an axial direction of the power feeding coil,

a direction of circulation of a magnetic flux generated by the first auxiliary coil and a magnetic flux generated by the second auxiliary coil are opposite to a direction of circulation of a magnetic flux generated by the power feeding coil, and

an axis of the first auxiliary coil and an axis of the second auxiliary coil are nonparallel to a power feeding direction of the power feeding coil, and are not aligned with an axis of the power feeding coil.

2. The power feeding coil unit according to claim 1, wherein

the axis of the first auxiliary coil and the axis of the second auxiliary coil are substantially perpendicular to the power feeding direction of the power feeding coil.

3. The power feeding coil unit according to claim 1, wherein

the first auxiliary coil and the second auxiliary coil are located on a rear side of the power feeding coil.

4. The power feeding coil unit according to claim 1, wherein

the power feeding coil includes a magnetic core, and each of the first auxiliary coil and the second auxiliary coil includes a magnetic core,

the magnetic core of the first auxiliary coil is coupled to the magnetic core of the power feeding coil, and

the magnetic core of the second auxiliary coil is coupled to the magnetic core of the power feeding coil.