High-frequency wire and coil

Patent metadata

Field	Value
Publication number	US-2016307666-A1
Application number	US-201415100765-A
Country	US
Kind code	A1
Filing date	Oct 24, 2014
Priority date	Dec 2, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

A high-frequency wire includes: a conductor portion which includes an inner layer formed of a material having lower conductivity than copper, and an outer layer which coats the inner layer and is formed of copper. In a frequency range of an AC current for using the high-frequency wire, in a case where a skin thickness δ [m] of a copper wire including a conductor portion formed of pure copper is defined as δ=√(2/ωσμ), a thickness t [m] of the outer layer satisfies 1.1δ<t<2.7δ. Here ω indicates an angular frequency of a current, which is represented by 2πf, μ indicates magnetic permeability [H/m] of the copper wire, σ indicates conductivity [Ω −1 m −1 ] of copper, and f indicates a frequency [Hz].

First claim

1 . A high-frequency wire comprising:
a conductor portion which comprises an inner layer formed of a material having lower conductivity than copper, and an outer layer which coats the inner layer and is formed of copper, wherein in a frequency range of an AC current for using the high-frequency wire, in a case where a skin thickness δ [m] of a copper wire including a conductor portion formed of pure copper is defined as δ=√(2/ωσμ), a thickness t [m] of the outer layer satisfies 1.1δ<t<2.7δ, here ω indicates an angular frequency of a current, which is represented by 2πf, μ indicates magnetic permeability [H/m] of the copper wire, σ indicates conductivity [Ω −1 m −1 ] of copper, and f indicates a frequency [Hz].

2 . The high-frequency wire according to claim 1 , wherein
the thickness t of the outer layer satisfies 1.3δ<t<2.7δ.

3 . The high-frequency wire according to claim 1 , wherein
the thickness t of the outer layer satisfies 2.0δ<t<2.7δ.

4 . The high-frequency wire according to claim 1 , wherein
an insulation coating layer is provided on an outer circumferential surface of the conductor portion.

5 . A high-frequency coil comprising:
the high-frequency wire according to claim 4 .

6 . A litz wire comprising:
a plurality of the twisted high-frequency wires according to claim 4 .

7 . A cable comprising:
the litz wire according to claim 6 , which is subjected to insulation coating.

8 . A coil comprising:
the litz wire according to claim 6 .

Assignees

• Fujikura Ltd

Inventors

• Kamidaki Chihiro
• Guan Ning
• MITSUNO Takafumi

Classifications

• H01F27/2823

  Wires (H01F27/2866 takes precedence) · CPC title

• H01B7/0009 Primary

  Details relating to the conductive cores · CPC title

• H01B7/17

  Protection against damage caused by external factors, e.g. sheaths or armouring · CPC title

• H01F5/06

  Insulation of windings · CPC title

• H01B7/30 Primary

  with arrangements for reducing conductor losses when carrying alternating current, e.g. due to skin effect · CPC title