JP2013125599A - Litz wire and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a Litz wire in which variation can be reduced when removing an insulation film from a terminal part, and to provide a manufacturing method therefor.SOLUTION: In a Litz wire 10 including an aggregation 14 formed by aggregating a plurality of insulated conductors 13 each having a conductor 11 and an insulation film 12 provided on the outer periphery of the conductor 11, the tip 15a of an insulated conductor 13a arranged on the inside of the aggregation 14 is located on the inside of the tip 15b of an insulated conductor 13b arranged on the outer peripheral side of the aggregation 14 in the longitudinal direction, and a cavity 16 is provided between the tip 15a of an insulated conductor 13a arranged on the inside of the aggregation 14 and the tip 15b of an insulated conductor 13b arranged on the outer peripheral side of the aggregation 14.

Description

  The present invention relates to a litz wire used as a high-frequency cable.

  When a single conductor is used for high-frequency communication equipment or the like for the wiring, the current distribution concentrates on the conductor surface as the frequency of the current flowing through the conductor increases, and the current density at the center of the conductor decreases. The “skin effect” reduces the effective cross-sectional area of the conductor, increases the AC resistance, and increases the conductor loss.

  For this reason, conventional high-frequency communication equipment, etc., uses a litz wire that divides a single conductor into multiple insulated conductors so that the conductor cross-sectional area is the same, and suppresses an increase in conductor loss due to the skin effect. It has been.

  4 and 5, as a general litz wire 40, a plurality of insulated conductors (enameled wires) 43 each having a conductor 41 and an insulating film 42 provided on the outer periphery of the conductor 41 are vertically attached (or Those formed by twisting) are known.

  Patent Documents 1 to 3 disclose a litz wire formed by twisting a plurality of insulated conductors so that a central portion has a uniform gap along the longitudinal direction.

  In the terminal treatment of these litz wires, it is necessary to remove the insulating film formed on the terminal portion. As a conventional method for removing the insulating film at the terminal portion, as shown in FIG. 6, the litz wire 63 is provided in a bathtub 62 filled with a solvent 61 for peeling the insulating film such as depent. There is a method of removing the insulating film 65 of the conductor 64 by immersing the terminal portion (for example, Patent Documents 3 and 4).

Japanese Patent Laid-Open No. 6-119827 JP-A-5-174638 JP 2005-108654 A JP 58-215905 A JP 2002-25821 A

  Conventionally, when removing the litz wire insulation film, the insulation film on the outer peripheral side of the litz wire and the other inner (center side) insulation film have different areas in contact with the solvent of the litz wire. There may be a time difference in removing the insulating film between the outer peripheral side and the inner side of the wire. As described above, when there is a time difference in removing the insulating film, the insulating film inside the litz wire may not be sufficiently removed and may remain.

  On the other hand, in order to completely remove the insulating film on the inner side of the litz wire, if the immersion time in the solvent is increased, there may be a problem that the conductor surface on the outer peripheral side of the litz wire is damaged by the solvent.

  In other words, there is a possibility that variations may occur in the state of removal of the insulating film between the outer peripheral side and the inner side of the litz wire.

  Then, the objective of this invention is providing the litz wire which can reduce the dispersion | variation at the time of removing the insulating film of a terminal part, and its manufacturing method.

  The present invention devised to achieve this object is a litz wire comprising an aggregate formed by assembling a plurality of insulated conductors having at least a conductor and an insulating film provided on the outer periphery of the conductor. The insulating conductor disposed on the inner side of the assembly is disposed such that the tip of the insulated conductor is present in the longitudinal direction relative to the tip of the insulating conductor disposed on the outer peripheral side of the assembly. It is a litz wire having a gap between the tip of the insulated conductor arranged on the inner side and the tip of the insulated conductor arranged on the outer peripheral side of the assembly.

  The gap may be provided at a plurality of locations at the tip of the assembly.

  Further, the present invention provides a litz wire manufacturing method comprising an assembly formed by assembling a plurality of insulated conductors having at least a conductor and an insulating film provided on an outer periphery of the conductor. By pulling the tip of the insulated conductor arranged at one end along the longitudinal direction, the tip of the other end of the insulated conductor arranged inside the assembly is arranged on the outer peripheral side of the assembly. The insulated conductor is disposed so as to be longer in the longitudinal direction than the distal end portion on the other end side of the insulated conductor, on the distal end portion on the other end side of the insulated conductor disposed inside the assembly and on the outer peripheral side of the assembly. It is a litz wire manufacturing method in which a gap is formed between the other end of the arranged insulated conductor.

  ADVANTAGE OF THE INVENTION According to this invention, the litz wire which can reduce the dispersion | variation at the time of removing the insulating film of a terminal part, and its manufacturing method can be provided.

It is sectional drawing which shows the litz wire which concerns on one embodiment of this invention. It is a fragmentary perspective view which shows the arrangement | positioning structure of the insulated conductor in the front-end | tip part of the litz wire of FIG. It is a perspective view which shows the litz wire which concerns on the modification of FIG. It is a perspective view which shows the conventional litz wire. It is sectional drawing which shows the conventional litz wire. It is a conceptual diagram which shows the method of removing the insulation coating of a litz wire.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  As shown in FIG. 1, the litz wire 10 according to the present embodiment includes a plurality of insulated conductors (enameled wires) 13 having at least a conductor 11 and an insulating film 12 provided on the outer periphery of the conductor 11. A formed assembly 14 is provided.

  As the conductor 11, a conductor such as copper or aluminum having a cross-sectional shape such as a round shape or a square shape can be used.

  As the insulating film 12, a resin generally used as an insulating film material for enameled wire, such as polyimide, polyamideimide, polyesterimide, and polyurethane, can be used.

  The plurality of insulated conductors 13 having the conductor 11 and the insulating coating 12 are gathered together by twisting or vertically attaching to form an aggregate 14. At this time, the insulated conductor 13 may be provided with a sheath or the like in addition to the conductor 11 and the insulating film 12. The assembly 14 has a structure in which a plurality of insulated conductors 13 each made of a different resin, in addition to a structure in which a plurality of insulated conductors 13 made of the same resin are gathered in the insulation film 12. It does not matter.

  Now, in the litz wire 10 according to the present embodiment, as shown in FIG. 2, the distal end portion 15a of the insulating conductor (first insulating conductor) 13a disposed inside the assembly 14 (center in FIG. 2) Arranged so as to be present by a predetermined distance D in the longitudinal direction from the tip 15b of the insulated conductor (second insulated conductor) 13b arranged on the outer circumferential side of the assembly 14 (the outer circumference of the insulated conductor 13a in FIG. 2). Is done. That is, the tip position of the insulated conductor 13a is offset to the center side in the longitudinal direction of the assembly 14 by a distance D from the tip position of the insulated conductor 13b.

  Therefore, the litz wire 10 has a gap 16 between the distal end portion 15a of the insulated conductor 13a disposed inside the assembly 14 and the distal end portion 15b of the insulated conductor 13b disposed on the outer peripheral side of the assembly 14. Hereinafter, what includes both the insulated conductor 13a and the insulated conductor 13b is referred to as an insulated conductor 13.

  In this embodiment, since the insulated conductor 13 having a round cross section (that is, the appearance is a cylindrical shape) is used, a cylindrical gap 16 corresponding to the appearance shape of the insulated conductor 13 is newly formed. Yes.

  However, the shape of the gap 16 is not limited to the cylindrical shape, and may be a polygonal column shape, a pyramid shape, or a conical shape. When it is desired to form a polygonal column-shaped gap 16, the outer shape of the insulated conductor 13 may be a polygonal column shape, and the tip of the insulated conductor 13 may be offset, and a pyramid-shaped or conical-shaped gap 16 may be formed. For this, the tip of the assembly 14 may be processed and formed.

  In the present embodiment, since the aggregate 14 is formed using seven insulated conductors 13, only the tip 15a of the single insulated conductor 13a disposed at the center of the aggregate 14 is offset. A gap 16 is formed only at one location. However, as shown in FIG. 3, when the assembly 14 is formed using a larger number of insulated conductors 13, the tip portions 15 a of the plurality of insulated conductors 13 a arranged inside the assembly 14 are formed. By offsetting a part (or all), gaps 16 can be formed at a plurality of locations at the tip of the assembly 14.

  In other words, in the present embodiment, one insulated conductor 13a is arranged at the center of the assembly 14 to form the first layer, and six insulated conductors 13b are arranged around the first layer. Although the Litz wire 10 having two layers formed and the second layer as the outermost layer has been described, the present invention is not limited to this, and a layer structure in which a plurality of layers are formed by the insulated conductors 13 on the outer periphery of the second layer. It does not matter. In addition, the first layer has been described as an example composed of only one insulated conductor 13a. However, the first layer is formed by twisting or vertically attaching a plurality of insulated conductors 13 together. It doesn't matter.

  In the case of the Litz wire having such a layer structure, not only a structure in which the void 16 is formed only in the first layer but also a structure having the void 16 in a plurality of locations on the inner layer than the outermost layer can be adopted. .

  In order to manufacture the litz wire 10, first, a plurality of insulated conductors 13 are twisted together at a relatively large twist pitch, or vertically assembled to form an aggregate 14.

  After that, the other end side of the insulated conductor 13a disposed inside the assembly 14 is pulled by pulling the tip of the insulated conductor 13a disposed inside the assembly 14 to one end side (the left side in the drawing) along the longitudinal direction. The distal end portion 15a (on the right side in the figure) is disposed so as to be present in the longitudinal direction relative to the distal end portion 15b on the other end side of the insulated conductor 13b disposed on the outer peripheral side of the assembly 14. At this time, if the twist pitch when forming the assembly 14 in the previous step is too small, the insulated conductor 13a cannot be pulled to one end side in this step, and the tip 15a of the insulated conductor 13a cannot be offset. .

  Through the above steps, the gap between the distal end portion 15a on the other end side of the insulated conductor 13a disposed inside the assembly 14 and the distal end portion 15b on the other end side of the insulated conductor 13b disposed on the outer peripheral side of the assembly 14 is performed. The gap 16 is formed in the gap, and the litz wire 10 according to the present embodiment is obtained.

  According to the litz wire 10 described so far, there is a gap between the distal end portion 15a of the insulated conductor 13a disposed inside the assembly 14 and the distal end portion 15b of the insulated conductor 13b disposed on the outer peripheral side of the assembly 14. 16, when the insulating film 12 of the litz wire 10 is removed, the insulating conductor 13 is present inside the assembly 14 (compared to the case where the tip 15a of the insulating conductor 13a is not offset). The area where the insulating film peeling solvent and the insulating conductor 13 are in contact with each other increases, and the effects of improving the removal efficiency of the insulating film 12 and shortening the processing time can be obtained.

  Moreover, by having the structure having the gaps 16 at a plurality of locations, the proportion of the space in the cross section of the assembly 14 is further increased, and the solvent for removing the insulating film 12 of the insulating conductor 13 and the insulating film 12 are in contact with each other. The area to be expanded can be further expanded.

  Therefore, according to the present invention, it is possible to reduce variations in removing the insulating film 12 at the terminal portion.

10 Litz wire 11 Conductor 12 Insulating film 13 Insulated conductor 13a Insulated conductor inside assembly (first insulated conductor)
13b Insulated conductor on the outer periphery side of the assembly (second insulated conductor)
14 Aggregate 15a Insulated conductor tip 15b on the inner side of the aggregate 16 Insulated conductor tip 16 on the outer peripheral side of the aggregate

Claims (3)

In a litz wire comprising an assembly formed by assembling a plurality of insulated conductors having at least a conductor and an insulating film provided on the outer periphery of the conductor,
The tip of the insulated conductor arranged inside the assembly is arranged so as to be present in the longitudinal direction from the tip of the insulated conductor arranged on the outer peripheral side of the assembly, and the inside of the assembly A litz wire characterized by having a gap between the tip of the insulated conductor disposed on the outer periphery and the tip of the insulated conductor disposed on the outer peripheral side of the assembly.   The litz wire according to claim 1, wherein the gap is provided at a plurality of locations at a tip portion of the aggregate. In a method of manufacturing a litz wire comprising an assembly formed by assembling a plurality of insulated conductors having at least a conductor and an insulating film provided on the outer periphery of the conductor,
By pulling the tip of the insulated conductor disposed inside the assembly to one end along the longitudinal direction, the tip of the other end of the insulated conductor disposed inside the assembly is moved to the end of the assembly. The insulating conductor disposed on the outer peripheral side is disposed so as to be longer in the longitudinal direction than the distal end portion on the other end side, and the distal end portion on the other end side of the insulated conductor disposed on the inner side of the assembly and the assembly A method for producing a litz wire, characterized in that a gap is formed between a distal end portion on the other end side of an insulated conductor arranged on the outer peripheral side of the body.