JP2014116094A - Electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for improving heat radiation performance from an outer peripheral surface of a conductive part in an electric wire.SOLUTION: An electric wire 10 is formed as pipe-shaped, and includes a conductive part 20 in which an outer peripheral surface 21 and an inner peripheral surface 23 form irregularities and a non-conductive jacket part 30 covering the outer peripheral surface 21 of the conductive part 20. The outer convex surface 212 of the outer peripheral surface 21 and the inner concave surface 231 of the inner peripheral surface 23 in the conductive part 20 are formed at a position of correspondence of the front and the rear (position of superimposing in the inside to outside direction), and the outer concave surface 211 of the outer peripheral surface 21 and the inner convex surface 232 of the inner peripheral surface 23 in the conductive part 20 are formed at a position of correspondence of the front and the rear (position of superimposing in the inside to outside direction).

Description

  The present invention relates to a technique for electric wires, and particularly to a technique for improving heat dissipation.

  When electricity is passed through the electric wire, the conductive portion of the electric wire generates heat. When the conductive part generates heat, the covering member covered by the conductive part may be melted, so that an allowable current amount is determined according to the cross-sectional area of the conductive part.

  Conventionally, the heat generation of the conductive portion is suppressed by increasing the cross-sectional area of the conductor portion. However, when the cross-sectional area of the conductive portion is increased, the electric wire becomes thicker, so the degree of freedom of wiring of the electric wire is reduced. In addition, since more material is required for the conductive portion, the electric wire becomes heavy and the material cost increases. Thus, further improvement is required for the technology for suppressing the heat generation of the electric wire.

  As an example of a technique for suppressing heat generation of the conductive portion, there is one described in Patent Document 1, for example. Specifically, in the technique of Patent Document 1, in a superconducting power transmission cable, a superconductor is cooled to a very low temperature by passing a cooling medium such as nitrogen gas through a pipe-shaped superconductor. Is.

JP 2009-9908 A

  However, the technique of Patent Document 1 is a superconducting power transmission technique, and is focused on cooling a superconductor using a cooling medium that passes inside a pipe. On the other hand, Patent Document 1 does not clearly disclose a technique for improving heat dissipation from the outer peripheral surface of the superconductor. It is expected that heat generation from the conductive portion is suppressed by increasing heat dissipation from the outer peripheral surface of the conductive portion.

  Then, an object of this invention is to provide the technique which improves the heat dissipation from the outer peripheral surface of the electroconductive part in an electric wire.

  In order to solve the above-mentioned problem, the first aspect is an electric wire, which is formed in a pipe shape, and has a conductive portion whose outer peripheral surface forms irregularities and a nonconductive property that covers the outer peripheral surface of the conductive portion. And a covering portion.

  Moreover, the 2nd aspect WHEREIN: In the electric wire which concerns on a 1st aspect, the internal peripheral surface of the said electroconductive part comprises unevenness | corrugation.

  Moreover, the 3rd aspect WHEREIN: The electric wire which concerns on a 2nd aspect WHEREIN: The convex surface of the said outer peripheral surface in the said electroconductive part and the concave surface of the said internal peripheral surface are formed in the position corresponding to the front and back, The said in the said electroconductive part The concave surface of the outer peripheral surface and the convex surface of the inner peripheral surface are formed at positions corresponding to the front and back surfaces.

  Moreover, a 4th aspect WHEREIN: The electric wire which concerns on any 1 aspect of a 1st-3rd aspect WHEREIN: The said outer peripheral surface of the said electroconductive part contains the concave surface and convex surface which extend along the longitudinal direction of the said electroconductive part. .

  Moreover, the 5th aspect WHEREIN: The electric wire which concerns on a 4th aspect WHEREIN: The outline of the cross section of the convex surface in the said outer peripheral surface of the said electroconductive part is formed along the uniform rectangle in the longitudinal direction of the said electroconductive part.

  According to a sixth aspect, in the electric wire according to any one of the first to fifth aspects, the material of the conductive portion includes copper.

  According to the electric wire which concerns on a 1st aspect, the surface area of an electroconductive part can be enlarged because the outer peripheral surface of the electroconductive part comprises the unevenness | corrugation. Thereby, the heat dissipation in the outer peripheral surface of an electroconductive part can be improved. Moreover, by providing the coating | coated part which coat | covers an outer peripheral side, the thermal radiation efficiency from the outer peripheral side of an electroconductive part can further be improved. Moreover, by making the conductive portion into a pipe shape, the cross-sectional area of the conductive portion can be made smaller than when the conductive portion has no cavity. Thereby, the material cost of an electroconductive part can be held down.

  Since the inner peripheral surface of the conductive part is uneven, the surface area of the conductive part can be further increased. Thereby, the heat dissipation of a conductive part can be improved.

  According to the third aspect, in the conductive portion, the thickness of the conductive portion is substantially uniform in the circumferential direction by causing the concave or convex position of the outer peripheral surface to correspond to the position of the convex or concave surface of the inner peripheral surface. Can be. Thereby, the amount of heat generated when electricity flows through the conductive portion can be made uniform in the circumferential direction.

  According to the electric wire which concerns on a 4th aspect, the recessed part and convex part which are extended along an electroconductive part can be easily shape | molded by outer peripheral surface by extrusion molding.

  According to the electric wire which concerns on a 5th aspect, the surface area of an electroconductive part can be enlarged more than the case where a cross-sectional outline is made into a circle under the conditions with the same width | variety and height.

  According to the electric wire which concerns on a 6th aspect, the electroconductivity of a conductive part can be improved because copper is contained in the raw material of a conductive part.

It is sectional drawing of the electric wire which concerns on 1st Embodiment. It is sectional drawing of the electric wire which concerns on 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the size and number of each part may be exaggerated or simplified as needed for easy understanding.

<1. First Embodiment>
<Construction of electric wire>
FIG. 1 is a cross-sectional view of the electric wire 10. The cross-sectional view shown in FIG. 1 is a view showing a cross section of the electric wire 10 (cut cut along a plane perpendicular to the longitudinal direction).

  The electric wire 10 includes a conductive portion 20 that extends along the longitudinal direction of the electric wire 10 and a non-conductive (insulating) covering portion 30 that covers the conductive portion 20 from the outside.

  The conductive part 20 is formed of, for example, a metal such as copper or aluminum or a mixture of two or more metals, and is a conductive part. By forming the conductive portion 20 with a material containing copper, the highly conductive electric wire 10 can be obtained. Moreover, the weight of the electric wire 10 can be reduced by using a material containing aluminum as the material of the conductive portion 20.

  The conductive portion 20 is formed in a pipe shape by forming a space 10 </ b> S extending along the longitudinal direction of the conductive portion 20 in the inside thereof. The space 10S inside the conductive portion 20 can be used as a cooling medium passage through which a cooling medium (liquid or gas) can pass. Liquid nitrogen may be employed as the cooling medium, but an inexpensive medium such as water or air containing an anticorrosive may be employed.

  Although illustration is omitted, when the cooling medium is passed from one end of the electric wire 10 toward the other end, the cooling medium may be pumped from one end side of the electric wire 10 by a pump or the like. By passing the cooling medium through the space 10S, the heat generated from the conductive portion 20 can be absorbed from the inside. For this reason, the electroconductive part 20 can be cooled efficiently.

  The outer peripheral surface 21 of the conductive portion 20 is uneven. More specifically, the outer peripheral surface 21 of the conductive portion 20 has four outer concave surfaces 211 and four outer convex surfaces 212 formed along the longitudinal direction of the conductive portion 20 alternately along the circumferential direction of the conductive portion 20. It is formed continuously. The four outer concave surfaces 211 and the four outer convex surfaces 212 are arranged at equal intervals around the outer periphery of the conductive portion 20. Each outer concave surface 211 is provided at a position between two outer convex surfaces 212, 212 adjacent to each other around the outer periphery of the conductive portion 20. In other words, the outer convex surfaces 212 and 212 are provided on both sides of the outer concave surface 211 in the circumferential direction, respectively.

  The four outer convex surfaces 212 are orthogonal to the longitudinal direction of the conductive portion 20 and protrude in each of the four outer directions orthogonal to each other. The outline of each of the four outer convex surfaces 212 in a cross-sectional view is composed of a pair of corners forming an angle of 90 ° and a straight line connecting the pair of corners. Further, the outline of the outer concave surface 211 in a cross-sectional view is composed of two straight lines that extend from the two corners of the adjacent outer convex surfaces 212 and 212 toward the center of the conductive portion 20 and intersect each other at approximately 90 °. Yes.

  The inner peripheral surface 23 of the conductive portion 20 is uneven. More specifically, the inner peripheral surface 23 of the conductive portion 20 is formed by alternately forming four inner concave surfaces 231 and inner convex surfaces 232 formed along the longitudinal direction of the conductive portion 20 in the circumferential direction of the conductive portion 20. Yes. The four inner concave surfaces 231 and the four inner convex surfaces 232 are arranged at equal intervals around the inner circumference of the conductive portion 20. Each inner concave surface 231 is provided at a position between two adjacent inner convex surfaces 232 and 232 around the inner periphery of the conductive portion 20. In other words, the inner convex surfaces 232 and 232 are respectively provided on both sides of the inner concave surface 231 in the circumferential direction.

  The outer convex surface 212 of the outer peripheral surface 21 and the inner concave surface 231 of the inner peripheral surface 23 of the conductive portion 20 are formed at positions corresponding to the front and back sides (positions overlapping in the inner and outer directions). In addition, the outer concave surface 211 of the outer peripheral surface 21 and the inner convex surface 232 of the inner peripheral surface 23 of the conductive portion 20 are formed at positions corresponding to the front and back sides (positions overlapping in the inner and outer directions). In the example of the electric wire 10 shown in FIG. 1, the conductive portion 20 is formed so that the cross-sectional shape of the outer peripheral surface 21 and the cross-sectional shape of the inner peripheral surface 23 are substantially similar. By forming the conductive portion 20 in this way, the thickness of the conductive portion 20 can be made substantially uniform in the circumferential direction. Thereby, the amount of heat generated when electricity is supplied to the conductive portion 20 can be made uniform in the circumferential direction of the conductive portion 20.

  As shown in FIG. 1, the outlines of the four outer convex surfaces 212 on the outer peripheral surface 21 of the conductive portion 20 are formed along a rectangle 90 (here, a square) that is uniform in the longitudinal direction of the conductive portion 20. For this reason, the surface area of the electroconductive part 20 can be made larger under the conditions where the width and height of the contour are the same, for example, compared with the case where the cross-sectional contour is a circle (such as a perfect circle or an ellipse).

  That is, when the rectangle 90 is assumed, when the cross-sectional outline (cross-sectional shape of the outer peripheral surface 21) of the conductive portion 20 that fits in the rectangle 90 is circular, the surface area of the conductive portion 20 is the smallest. On the other hand, as shown in FIG. 1, when irregularities are formed on the outer peripheral surface 21 of the conductive portion 20 while being accommodated in the same rectangle 90, the vertical and horizontal widths are made the same as (or made smaller) than when circular. ), The surface area of the conductive portion 20 can be increased, that is, the heat dissipation can be increased.

  The conductive part 20 can be manufactured by, for example, extrusion molding. According to the extrusion molding, the outer peripheral surface 21 of the conductive portion 20 can be easily formed into an outer concave surface 211 and an outer convex surface 212 extending along the longitudinal direction of the conductive portion 20. Further, the inner peripheral surface 23 of the conductive portion can be easily formed into the inner concave surface 231 and the inner convex surface 232 extending along the longitudinal direction of the conductive portion 20 by extrusion molding. However, manufacturing the conductive part 20 by a method other than extrusion is not hindered.

  The covering portion 30 is made of a material such as polyvinyl chloride, polyethylene, fluororesin, or polyester. By covering the outer peripheral portion of the conductive portion 20 with the covering portion 30, the conductive portion 20 can be insulated from the outside, or the conductive portion 20 can be protected from the outside. Moreover, according to the coating | coated part 30, the thermal radiation from the outer peripheral surface 21 of the electroconductive part 20 can also be accelerated | stimulated.

  The thickness of the covering portion 30 in the inner and outer directions is not particularly limited as long as it is sufficient to sufficiently insulate and protect the conductive portion 20 under the required conditions. However, in order to make the electric wire 10 as thin as possible, it is desirable that the thickness of the covering portion 30 in the circumferential direction be uniform. From such a viewpoint, in the example of the electric wire 10 shown in FIG. 1, the covering portion 30 is formed so as to form an unevenness corresponding to the unevenness formed by the outer peripheral surface 21 of the conductive portion 20. The covering portion 30 can be formed by extrusion as with a general electric wire.

<Effect>
According to the electric wire 10 which concerns on this embodiment, the surface area of the electroconductive part 20 can be enlarged because the outer peripheral surface 21 of the electroconductive part 20 is uneven | corrugated. Thereby, the heat dissipation in the outer peripheral surface 21 of the electroconductive part 20 can be improved. Moreover, by providing the coating | coated part 30 which coat | covers an outer peripheral side, the thermal radiation efficiency from the outer peripheral side of an electroconductive part can further be improved. Moreover, by making the conductive part 20 into a pipe shape, the cross-sectional area of the conductive part 20 can be reduced as compared with the case where the conductive part 20 has no cavity. Thereby, the material cost of the electroconductive part 20 can be held down.

  Further, since the inner peripheral surface 23 of the conductive portion 20 is uneven, the surface area of the conductive portion 20 can be further increased. Thereby, the heat dissipation of the electroconductive part 20 can be improved. However, it is not an essential configuration that the inner peripheral surface 23 of the conductive portion 20 is uneven. It is not hindered to form the conductive portion 20 so that the inner peripheral surface 23 of the conductive portion 20 forms a smooth annular surface. Further, in order to promote heat radiation from the inner peripheral surface 23 (that is, to improve the heat emissivity), appropriate surface processing (for example, formation of an oxidized surface, formation of a resin layer or a ceramic layer) is performed on the inner peripheral surface 23 You may go.

<2. Second embodiment>
An electric wire 10A according to the second embodiment will be described. FIG. 2 is a cross-sectional view of the electric wire 10A according to the second embodiment. In addition, FIG. 2 is a figure which shows the cross section of 10 A of electric wires.

  Similarly to the electric wire 10, the electric wire 10 </ b> A includes a pipe-shaped conductive portion 20 </ b> A in which a space 10 </ b> SA is formed and a covering portion 30 </ b> A that covers the outer peripheral side of the conductive portion 20 </ b> A. A cooling medium can be passed through the space 10SA.

  The outer peripheral surface 21 </ b> A of the conductive portion 20 </ b> A of the electric wire 10 </ b> A is uneven as in the outer peripheral surface 21 of the conductive portion 20. However, the outer peripheral surface 21A of the conductive portion 20A is a boundary portion between the six outer convex surfaces 212A that are arc-shaped portions that bulge and bulge outwardly in a cross sectional view, and the two outer convex surfaces 212A and 212A that are adjacent in the circumferential direction. And the outer concave surface 211A corresponding to. The bottom of the outer concave surface 211A forms an acute angle. The outer concave surface 211A and the outer convex surface 212A extend along the longitudinal direction of the conductive portion 20A.

  In the present embodiment, in the electric wire 10A, the six outer convex surfaces 212A on the outer peripheral surface 21 of the conductive portion 20A are provided so as to be in contact with a regular regular hexagon 90A in the longitudinal direction of the conductive portion 20.

  Further, the inner peripheral surface 23A of the conductive portion 20A is uneven. More specifically, the inner peripheral surface 23A of the conductive portion 20A corresponds to a boundary portion between six inner concave surfaces 231A that are arc-shaped portions that are curved and concaved outwardly and two outer convex surfaces 212 that are adjacent in the circumferential direction. The inner convex surface 232A is used. The inner concave surface 231A and the inner convex surface 232A extend along the longitudinal direction of the conductive portion 20A.

  The outer convex surface 212A of the outer peripheral surface 21A and the inner concave surface 231A of the inner peripheral surface 23A of the conductive portion 20A are formed at positions corresponding to the front and back (overlapping positions in the inner and outer directions). In addition, the outer concave surface 211A of the outer peripheral surface 21A and the inner convex surface 232A of the inner peripheral surface 23A of the conductive portion 20A are formed at positions corresponding to the front and back (overlapping positions in the inner and outer directions).

  Also in the electric wire 10 </ b> A, the outer peripheral surface 21 </ b> A of the conductive portion 20 </ b> A is uneven so that heat dissipation can be improved. Moreover, material cost can be restrained because the electroconductive part 20A is made into pipe shape.

  The cross-sectional shape of the conductive portions 20 and 20A is not limited to the above. The conductive portion may have any cross-sectional shape as long as the outer peripheral surface is a pipe-like shape.

  As mentioned above, although this invention was demonstrated in detail, above-described description is an illustration in all the aspects, Comprising: This invention is not limited to it. It is understood that countless variations that are not illustrated can be envisaged without departing from the scope of the present invention.

1010A Electric wire 10S, 10SA Space 20, 20A Conductive portion 21, 21A Outer peripheral surface 211, 211A Outer concave surface 212, 212A Outer convex surface 23, 23A Inner peripheral surface 231, 231A Inner concave surface 232, 232A Inner convex surface 30, 30A Covering portion 90 Rectangular

Claims (6)

An electric wire,
A conductive part that is formed in a pipe shape and has an uneven outer peripheral surface;
A non-conductive covering portion covering the outer peripheral surface of the conductive portion;
An electric wire. The electric wire according to claim 1,
An electric wire in which an inner peripheral surface of the conductive portion is uneven. The electric wire according to claim 2,
The convex surface of the outer peripheral surface and the concave surface of the inner peripheral surface in the conductive portion are formed at positions corresponding to the front and back surfaces, and the concave surface of the outer peripheral surface and the convex surface of the inner peripheral surface in the conductive portion correspond to the front and back surfaces. An electric wire that has been formed. In the electric wire according to any one of claims 1 to 3,
The electric wire in which the outer peripheral surface of the conductive part includes a concave surface and a convex surface extending along a longitudinal direction of the conductive part. The electric wire according to claim 4,
The contour of the cross section of the convex surface on the outer peripheral surface of the conductive portion is an electric wire formed along a uniform rectangle in the longitudinal direction of the conductive portion. In the electric wire according to any one of claims 1 to 5,
An electric wire containing copper in a material of the conductive part.

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