JPH04223009A - Manufacture of self-fusible litz wire - Google Patents

Abstract

PURPOSE:To prevent foaming of a self-fusible layer due to air existing in gaps between insulative element wires by coating the whole periphery of an insulative strand wire with a self-fusible powder coating material so as to form the self- fusible layer. CONSTITUTION:To whole periphery of a single conductor 2 is coated with an insulative coating material, followed by baking repeatedly, thus obtaining for an insulative layer 3. As a result, an insulative element wire 4 an be obtained. A plurality of insulative element wires 4 are twisted, thereby obtaining an insulative strand wire 5. The whole periphery of the strand wire is coated with a powder coating material. Consequently, a self-fusible layer 6 can be formed, resulting in completion of a self-fusible litz wire 1. Therefore, heating can be dispensed in forming the layer 6 so that foaming of the layer 6 cannot be generated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a self-fusing litz wire having a self-fusing layer on its outer periphery, which is used as a winding wire for a coil or the like that supplies high-frequency current.

0002

2. Description of the Related Art In recent years, it has been desired to improve the performance of coils for electronic parts and electrical equipment, and coils that supply high-frequency current have been developed. In this case, it is strongly desired to efficiently reduce the heat generation of the coil conductor in response to high frequencies in order to maintain safety and obtain stable and good characteristics. As a countermeasure to this problem, a Litz wire has been developed, which has a structure in which multiple insulated wires are twisted together with an insulating layer provided around the entire outer periphery of a single-core conductor.

Conventionally, an insulating layer is formed by repeatedly applying and baking an insulating paint over the entire outer circumference of a single-core conductor to obtain an insulated strand, a plurality of the insulated strands are twisted together to form an insulated stranded wire, and the insulated stranded wire is A method for manufacturing a self-fusing litz wire is known, in which a self-fusing litz wire is repeatedly coated and baked on the entire outer periphery of the wire.

When a coil is wound using a self-bonding litz wire 1 as shown in FIG. 2 manufactured according to the above manufacturing method, a self-bonding layer 6 is formed on the entire outer periphery of the insulating stranded wire 5. Therefore, the single-core conductors 2, 2 forming the insulated stranded wire 5
, ... and insulating layers 3, 3, ... provided on the entire outer periphery of the insulated wires 4, 4, ... are prevented from unraveling or twisting during coil winding, so the coil winding is always normal. It is possible to do this. In addition, since the self-fusing layer 6 is evenly formed over the entire outer circumference of the self-fusing litz wire 1, the fusing force between each self-fusing litz wire is large, providing an extremely strong and reliable coil. can do.

[0005]

[Problems to be Solved by the Invention] However, when attempting to manufacture the self-fusion litz wire 1 by the above manufacturing method, each of the insulated strands 4 forming the insulated stranded wire 5,
4, Air exists in the void formed between... and the self-fusing layer 6
When forming the self-adhesive layer 6, the air accumulated in the gaps between the insulating wires 4, 4, . However, it was not possible to obtain a self-fused litz wire with good appearance.

[0006] Therefore, the present invention aims at producing a self-welding litz wire that can prevent each insulated wire from coming apart or twisting during coil winding, has a large welding force, and has a good appearance. The purpose of the present invention is to provide a method for manufacturing a litz wire.

[0007]

SUMMARY OF THE INVENTION The above objects are achieved by the present invention. In summary, the present invention provides an insulating layer by repeatedly applying and baking an insulating paint over the entire outer periphery of a single-core conductor to form an insulated strand, twisting a plurality of the insulated strands together to form an insulated stranded wire, and This is a method for producing a self-fusing litz wire, which is characterized in that the entire outer periphery of the wire is powder-coated with a self-fusing powder coating to form a self-fusing litz wire.

[0008]

[Function] In the method for manufacturing a self-fusing litz wire of the present invention, a self-fusing powder coating is powder coated on the entire outer periphery of the insulated stranded wire to form a self-fusing layer. Unlike conventional manufacturing methods in which a self-adhesive layer is formed by repeating coating and baking, there is no need to apply heat during the formation of the self-adhesive layer, and the self-adhesive layer does not foam.

[0009]

[Example] An example of the method for manufacturing a self-fused litz wire of the present invention will be described below.

In order to manufacture the self-fusing litz wire 10 shown in FIG. 1, an insulating layer 13 is formed by repeatedly applying and baking a polyimide insulating paint over the entire outer periphery of the copper single-core conductors 12, 12, . , 13, . . . and insulated wires 14, 14,
..., seven insulated wires 14, 14, ... are twisted together to form an insulated stranded wire 15, and then the entire outer periphery of the insulated stranded wire 15 is
A self-adhesive layer 16 is provided by powder coating a polyester self-adhesive powder coating by an electrostatic dynamic dipping method or the like.

Since the self-fusing layer 16 of the self-fusing litz wire 10 manufactured according to the manufacturing method of the present invention is formed by powder coating, the self-fusing layer 16 is self-fused by repeating the application and baking of the self-fusing paint. There is no need to apply heat when forming a self-adhesive layer, unlike in conventional manufacturing methods in which an adhesive layer is formed. Therefore, foaming of the self-bonding layer due to the expansion of air existing in the gaps formed between the respective insulating strands 14, 14, . . . does not occur, and a self-bonding litz wire with a good appearance can be obtained.

Note that the self-fusing litz wire 10 of the above embodiment
In the above, insulated wires 14, 14, which have insulating layers 13, 13, .
Although the insulated stranded wire 15 is made by twisting seven wires together, the type and size of the conductor, the material of the insulating layer, the number of strands, etc. can be changed freely according to the purpose. Furthermore, although polyester resin is used as the resin powder in the above embodiments, other resin powders such as polyethylene, nylon, and polyvinyl butyral may also be used.

[0013]

Effects of the Invention In the method for manufacturing a self-fusing litz wire of the present invention, a self-fusing powder coating is powder coated on the entire outer periphery of the insulated stranded wire to form a self-fusing layer. Unlike the conventional manufacturing method, which forms a self-adhesive layer by applying adhesive paint and baking it, there is no need to apply heat when forming the self-adhesive layer, so there is no need to apply heat between each insulated wire that makes up the insulated stranded wire. Foaming of the self-adhesive layer, which occurs due to the expansion of air existing in the voids created by the process, does not occur.

Therefore, it is possible to prevent the individual insulating wires constituting the self-fused litz wire from coming apart or twisting during coil winding, and the self-fused litz wire has a high welding force and a good appearance. wire can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a self-fusing litz wire manufactured by an embodiment of the self-fusing litz wire manufacturing method of the present invention.

FIG. 2 is a cross-sectional view showing a self-fusion litz wire manufactured by a conventional self-fusion litz wire manufacturing method.

[Explanation of symbols]

12...Single core conductor 13...Insulating layer 14...Insulated wire 15...Insulated stranded wire 16...Self-fusing layer

Claims (1)

[Claims] [Claim 1] Application of insulating paint to the entire outer periphery of the single-core conductor,
Baking is repeated to provide an insulating layer to obtain an insulated wire, a plurality of the insulated wires are twisted together to form an insulated stranded wire, and the entire outer periphery of the insulated stranded wire is powder coated with a self-bonding powder coating. A method for producing a self-fused litz wire, characterized in that the self-fused litz wire is made into a self-fused litz wire.