JPH02242531A - Litz wire - Google Patents

Abstract

PURPOSE:To enhance the space factor of a litz wire in a coil by arranging and stranding enameled wires of circular cross section into two horizontal lines so as to form a flat type stranded cable the total cross section of which is rectangular. CONSTITUTION:Enameled element wires 1A, 1A each comprising an enamel coat 2 on a conductor 1 are stranded into two horizontal lines so as to form a flat type stranded cable the total cross section of which is rectangular. In order to thus strand the wires into a flat shape, the enameled wires 1A, 1A are fed from the feed bobbins 21, 21 of a feeder 20, and are stranded into a flat shape on a flat angle stranding dice 22, and are then made to pass through a molding dice 24 to adjust their total form, and then they are wound up by a winder 25. It is thus made possible to obtain a litz wire of excellent space factor without addition of too much stress.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention provides an improved method that can improve the high frequency gain, improve the space factor during winding, and further prevent the looseness of the wire. [Conventional technology 1] Litz wires, which are made by twisting enamelled wires to make them multi-conductor, have been used since early times in high-frequency communication equipment, etc.
As the frequency of the current increases, the AC resistance increases due to the skin effect and the resistance becomes larger. The purpose is to divide the skin current 7 and prevent the increase in AC resistance mentioned above. 6 In recent years, as electrical equipment has become smaller, more efficient, and more energy efficient, inverter control has become more frequent. I=゛B is used to improve image quality in the deflection yoke of TVs, etc.
As the T drive frequency becomes higher, the demand for Litz wires is increasing.9 Knotts wires are made by twisting together many enamelled wires as described in 1 above, or by twisting them together. Regardless of whether the twisting method is concentric twisting, collective twisting, or compound twisting, when the terminals are cut, the strain during twisting is released all at once, and the strands tend to fall apart, making it difficult to wind coils. There was a problem that terminal processing became extremely troublesome.

In addition to the above-mentioned problem of terminal processing, if the wires tend to come apart as mentioned above, when the wires are wound on a rectangular bobbin, the twisted shape of the wires will be crushed at the corners, making it difficult to wind the wires smoothly. There are also problems.

Therefore, in a Litz wire made by twisting a plurality of strands of enameled wire, the applicant has proposed that at least one of the strands is made of a self-bonding enameled wire, and that the self-bonding enameled wire is We separately proposed a Litz wire that could solve the problem described in item 1 by placing it between the enamelled wires.

[Invention or Problem to be Solved] The above problem has solved the problem of bare wires, which can be said to be a fateful problem for Litz wires, but Litz wires still have the problem of a decrease in space factor. 6 In other words, the conventional litz wire has an enamel coating 2 on the conductor 1.
An enameled wire coated with 1. As shown in FIG. 8, A and LA were usually twisted concentrically, in clusters, or in combination to form a stranded wire with an overall circular cross section.

When such twisted wires having a circular cross section are wound, the space factor inevitably decreases, which is a major bottleneck in the miniaturization and labor saving of the aforementioned equipment.

In order to improve this space factor, it has been proposed to twist the litz wires and then roll the whole into a rectangular shape as shown in FIG. However, in the case of forced deformation in this way, a very large stress is applied to the strands IA particularly located in the central part, and the elongation and distortion of the enamel film 2 become large. There was a great risk of cracking in the film 2, causing pinholes, and impairing insulation reliability, which was a practical problem.

The object of the present invention is to provide a novel litz wire that can effectively solve the problem of the space factor of the litz wire mentioned above, and can also have an excellent space factor and solve the problem of cable wire bulges at the same time. .

[Means for Solving the Problems] The gist of the present invention is to arrange and strand a plurality of enamelled wires each having a circular cross section in a #12 row, thereby forming a flat stranded wire having a rectangular overall cross section. This is due to the fact that it is configured so that
In that case, one or more of the wires constituting the flat stranded wire is made of self-bonding enamelled wire, mixed between ordinary enamelled wires, and after being twisted into the flat stranded wire, 6 [Action 1: As in the conventional example, the stranded wire with a circular cross section is Instead of rolling the wires into a rectangular shape, when twisting the wires, arrange the wires in two horizontal rows and twist them so that they have a rectangular cross section. [Example] The present invention will be described below with reference to Examples.7 Figure 1 is a perspective view of a litz wire according to the present invention.
The figure is an end view thereof. In the present invention, an enameled wire 1. A and LA are twisted in two rows horizontally as shown in the figure, so that the entire # section becomes a flat stranded wire with a rectangular shape.

In order to twist it into a flat shape like this, as shown in Figure 3,
The enameled cable wires IA and LA are sent out from the delivery pobbins 21 and 21 of the delivery device 20, twisted into the above-mentioned flat shape in the flat twisting ties 22, and then passed through the forming ties 24 to change the overall shape. Alternatively, it may be wound up using the winding machine 25.

In order to more completely prevent the looseness of the strands, which would otherwise occur during winding, if this shaping tie 24 is not provided, all the strands are normally enameled strands IA as described above. , iA, as shown in FIGS. 4 and 5, a part of the wire is coated with a self-bonding enamel film having an enamel film 2 on the conductor 1 and a self-bonding skin v3 thereon. Bare wire IB,
The heating device 23 (
It is best to install a device (which may be heated with electricity) to make it self-fuse.
This makes it possible to sufficiently prevent the looseness of the strands.

Furthermore, as shown in FIG. 7, the flat stranded wire 10 may be rolled and welded from the short side direction at a reduction rate of 5 to 40% using a rolling roll 26, so as to be configured as shown in FIG. 6. Thereby, the space factor can be further improved. (With a rolling reduction ratio of 40%, it is possible to increase the space factor from 60% before rolling to 85% after rolling.) Experiments have shown that with a rolling reduction ratio of 5 to 40%, the occurrence of pinholes can be eliminated. Confirmed 9
Litz wires having the configurations shown in Figures 2, 4, and 5 above were arranged in two layers of 7 wires each using 0.2111 m diameter enameled wire (2UEW) and self-bonding enameled wire (28B3UEW), resulting in 14 wires. After manufacturing flat stranded wires, each wire was wound into a square pobbin, and no crushing phenomenon was observed at the corners, indicating good winding performance.2
[Effects of the Invention] As described above, according to the Litz wire according to the present invention, the space factor in the winding can be improved, and at least one of the strands is made of a self-bonding enamelled wire. By doing so, it is possible to prevent looseness between the strands, which is very useful in industry.

[Brief explanation of drawings]

Fig. 1 is a perspective view of an embodiment according to the present invention, Fig. 2 is an end view thereof, Fig. 3 is an explanatory diagram of the manufacturing device, and Figs. 4 to 6 show three other embodiments according to the present invention. FIG. 7 is an explanatory view showing the state of rolling, and FIGS. 8 and 9 are end views showing two types of conventional examples. 1: Conductor, IA: Ordinary enameled wire, 1B = Self-bonding enameled wire, 2: Enamel coating, 3: Self-bonding coating, 10: Flat stranded wire, : Rolled flat stranded wire. Agent Patent Attorney Daito Sato Fujio

Claims (3)

[Claims] (1) A Litz wire made by arranging and twisting a plurality of enamelled wires with circular cross sections in two horizontal rows to form a flat stranded wire with a rectangular overall cross section. (2) The litz wire according to claim 1, wherein at least one of the strands constituting the flat stranded wire is composed of a self-bonding enameled wire, and is mixed between ordinary enameled wires. (3) After twisting into a flat stranded wire, the reduction rate is 5 in the short side direction.
The litz wire according to claim 1 or 2, which is entirely deformed by rolling in a range of .about.40%.