Coaxial cable and medical cable using same

Patent metadata

Field	Value
Publication number	US-9734934-B2
Application number	US-201514944945-A
Country	US
Kind code	B2
Filing date	Nov 18, 2015
Priority date	Nov 19, 2014
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A coaxial cable includes a central conductor, and an electrical insulator formed around a circumference of the central conductor. The electrical insulator is made of an electrical insulating tape wrapped and overlapped around the circumference of the central conductor. The electrical insulating tape includes a plurality of voids formed on one outer circumferential surface.

First claim

What is claimed is:

1. A coaxial cable, comprising:
a central conductor having a diameter equal to or less than AWG48;
an electrical insulator formed around a circumference of the central conductor, the electrical insulator comprising an electrical insulating tape having a thickness equal to or less than 30 μm wrapped and overlapped around the circumference of the central conductor, the electrical insulating tape including a plurality of uniformly dispersed voids formed at an equal pitch on one outer circumferential surface, the electrical insulating tape comprising a void containing layer, which is formed with the voids thereon, and a reinforcing layer, which is thermally fused and bonded to the void containing layer; and
a shield around the electrical insulator,
wherein the void containing layer has a lower relative permittivity, a lower mechanical strength and a larger thickness than the reinforcing layer.

2. The coaxial cable according to claim 1 , wherein the void containing layer comprises polytetrafluoroethylene or polyethylene, and the reinforcing layer comprises polyethylene terephthalate.

3. The coaxial cable according to claim 1 , wherein the voids penetrate through the void containing layer.

4. The coaxial cable according to claim 1 , wherein the voids are round, and are staggered at each equal pitch.

5. The coaxial cable according to claim 1 , further comprising: a protector formed around a circumference of the electrical insulator.

6. The coaxial cable according to claim 5 , wherein the protector is made of a protective tape, which is wrapped around a circumference of the electrical insulator, or a protective layer, which is non-fully extruded and molded around a circumference of the electrical insulator.

7. A medical cable, comprising: a bundle of core units each of which comprises a plurality of the coaxial cables according to claim 1 stranded together.

8. The coaxial cable according to claim 1 , wherein the electrical insulating tape is helically wrapped and overlapped around the circumference of the central conductor such that the reinforcing layer contacts the central conductor.

Assignees

• Hitachi Metals Ltd

Inventors

• Huang Detian
• Watanabe Takanobu
• Kudo Kimika
• Watanabe Haruyuki

Classifications

• H01B11/1847

  of helical wrapped structure · CPC title

• H01B11/1839

  of cellular structure · CPC title

• H01B3/423

  Linear aromatic polyesters · CPC title

• H01B3/441 Primary

  from alkenes · CPC title

• H01B1/02

  mainly consisting of metals or alloys · CPC title