JPH03152808A - Transposed rectangular conductor insulated wire - Google Patents

Abstract

PURPOSE:To ease the friction by the contact of an element wire angle part without increasing the element wire diameter even if the winding diameter is small at the time of coil winding by providing a powder coating layer by a lubricating resin on the angle part of an insulating rectangular conductor having a powder coating insulating layer. CONSTITUTION:A plurality of insulating rectangular conductors are used as element wires and dislocated to form a stranded conductor, and a common insulating layer is provided on the outside thereof to form a transposed rectangular conductor insulated wire. When such an insulated element wire 12 is formed while providing a powder coating layer 15 by a lubricating resin in the longitudinal direction of the angle part of a rectangular conductor 11 having a powder coating insulating layer 14, the friction by the angle part between the adjacent element wires 12 is remarkably eased by the layer 15 even when the winding diameter is small at the time of coil winding by use of the transposed rectangular conductor insulated wire, preventing the generation of breakage, and also an increase in outer diameter of the element wire is prevented because of the partial lamination.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transposed rectangular conductor insulated wire with improved coil workability.

(Prior Art) Conventionally, as an insulated rectangular conductor used as a wire for a transposed rectangular conductor insulated wire, an insulated rectangular conductor made of aluminum or copper and coated with synthetic enamel has been used.

Such an insulated rectangular conductor is obtained by repeating the process of applying and baking the above-mentioned synthetic enamel insulating paint on the surface of the conductor 510 times to form an insulating film of a desired thickness. Then, using the obtained conductor as a wire, the desired number of wires are twisted together while being transposed in a conventional manner to form a twisted conductor, and the outer periphery is further covered with insulating paper, synthetic resin film, various organic and inorganic fiber papers. An insulated wire is obtained by winding an electrically insulating tape made of cloth or the like to provide a common insulating layer.

However, such rectangular insulated wires with enamel insulation require many steps to apply enamel to the wires and bake them as described above.
In particular, rectangular conductors used in such applications have a larger cross-sectional area than the enamelled round wires used in small rotating machines, transformers, etc., so seizures can sometimes occur due to a large amount of heat heating up the conductor itself. There was a problem that energy costs were extremely high.

Therefore, it was proposed to use a synthetic resin powder-coated insulated conductor instead of the above-mentioned enamel insulation (for example,
3-165534). This powder-coated insulated conductor is made by applying solvent-free powdered resin such as epoxy resin onto an aluminum or copper conductor using an electrostatic coating method to achieve the desired thickness in one operation, followed by heating and baking. It's something you can get by going. Therefore, not only the above-mentioned energy cost problem is alleviated, but also it is favorable in terms of pollution and working environment since no solvent is used.

(Problems to be Solved by the Invention) However, on the other hand, since a film with a thickness of several tens of microns is formed in one coating, the mechanical properties deteriorate, and the unevenness caused by melting the powder remains on the finished surface, making it smooth. There is a problem with sexuality.

In other words, using such powder-coated insulated rectangular conductors as wires does not cause any problems under normal usage conditions, but when trying to reduce the coil diameter in order to downsize a transformer, for example, the mechanical properties mentioned above may be affected. Another problem is that the insulating layer at the dislocation portion of the wire is easily damaged due to its smoothness.

Specifically, as shown in FIG. 7, a desired number of strands 2 each having an insulating layer 4 formed on a rectangular conductor 1 are bundled as shown in FIGS. It is covered with a common insulating layer 3. Immediately before the above-described dislocation occurs, the lower right corner of the strand 2 is lifted from the lower strand and contacts the upper left corner of the strand 2 on the right side at point A.

Such contacts always exist at all dislocation sites, but when these are wound into small-diameter coils, there is mutual misalignment before and after contact A, which weakens the mechanical strength of the wire insulation layer mentioned above. In many cases, the film will be damaged.

Several proposals have been made to improve the mechanical properties of such powder coated wires. For example, Utsukai Showa 59-9
8504 is an insulated wire in which an insulating film is formed on the conductor surface by electrostatic powder coating, and a layer of anti-friction agent is further provided on the film. As the flat insulated wires, insulated wires made of self-lubricating powder resin are used, and the slipperiness of the surface of the wires is improved.

However, the reality is that none of these insulated wires has been able to sufficiently solve the problem of damage to the wire coating caused by the reduction in the coil winding diameter.

(Means for Solving the Problems) The present inventors have completed this invention as a result of intensive studies to solve the problems.

That is, the present invention provides a transposed rectangular conductor insulated wire in which a plurality of insulated rectangular conductors are used as strands, and a twisted conductor is formed by transposing them, and a common insulating layer is provided on the outside thereof. , an insulation in which a powder coating insulation layer is provided on the conductor, and then a powder coating layer made of a lubricating resin is further provided on at least one corner of the four corners of the rectangular conductor cross section along the longitudinal direction. This is a transposed rectangular conductor insulated wire characterized by the use of strands.

Specifically, as shown in FIGS. 1 to 3, the wire 12 of the present invention has an insulating layer 14 coated with powder on a rectangular conductor ll.
Furthermore, a lubricating resin is applied to at least one corner, such as one of the cross-sectional corners (Fig. 1), two diagonal corners (Fig. 2), or all corners (Fig. 3). Powder coating layer 1 by
5.

Then, as shown in FIG. 4, the obtained wires 12 are twisted together while being transposed according to a conventional method, and an external common insulating layer 13 is provided to obtain an insulated wire 10.

The powder coating for wire insulation used in the present invention includes:
Although not particularly limited, the target transposed rectangular conductor insulated wire is used in large-capacity oil-immersed transformers for boat fishing, so epoxy resin powder with particularly excellent hydrolysis resistance and oil resistance is used. Body paints are preferred.

In addition, as a lubricating resin powder coating for the corners of the wire, it is necessary to have excellent lubricity and abrasion resistance as described above, as well as the above-mentioned hydrolysis resistance and oil resistance. For example, nylon 11. Nylon 12°, nylon 6, nylon 61O, nylon 66, and copolymerized nylons thereof, as well as PFA and FEP.

A powder coating made of fluororesin such as ETFB is suitable.

Further, in this invention, the reason why the lubricating layer for the slipperiness of the corner portion of the strand is powder coated is not limited to the above-mentioned pollution and environmental problems.

Another reason is that this can be easily achieved by once powder-coating the entire outer surface of the wire insulating layer with a lubricating resin, and then mechanically wiping off unnecessary portions of the powder-coating material before heating and melting.

Furthermore, in the present invention, the lubricating layer is not provided on the entire outer surface of the wire insulating layer as in the above conventional example, but only on a part of it. There's a reason.

That is, the particle size of powder coatings is generally about 10 pm or more because of the efficiency of electrostatic coating, and the particle size of lubricating resins, especially nylon powder coatings, is about 40 pm because it is difficult to reduce the diameter. It is very difficult to form a thin film because such relatively large particles are coated and melted to form a film. As in the present invention, there is also a rational reason why the finished dimensions can be kept low when the necessary contact portions are transposed and twisted.

(Function) In the present invention, in the above-mentioned insulated conductor wire, after providing a powder coating insulating layer on the conductor as the insulated rectangular conductor, at least one of the four corners of the cross section of the rectangular conductor is further applied. An insulated wire is used in which a powder coating layer of a lubricating resin is provided along the longitudinal direction on each corner of the wire. Friction caused by contact between the raised strand corner and the adjacent strand corner at the dislocation portion is significantly alleviated. Since the above-mentioned lubricating coating is applied only partially, there is no need to increase the diameter of the stranded wire of the intended insulated wire.

(Example) The present invention will be specifically explained below with reference to Examples.

Reference Example 2 Using a rectangular copper conductor with a 7-body structure, an epoxy powder coating (ECP2O8, manufactured by Jumen Durez Co., Ltd.) was applied on the rectangular copper conductor using an electrostatic powder coating method, and the film was heated and baked to a film thickness of 60 mm.
-3 The insulated wire had a breakdown voltage of 5.4 KV.

Eleven of the obtained insulated strands were twisted by a conventional method at a pitch of 120 mm, and an insulating paper having a thickness of 0.4 mm was wound around the outside to obtain a transposed rectangular conductor insulated wire.

Example 1 Approximately 40 pmJ of nylon-based powder paint (Rusan Powder manufactured by Nihon Rilsan Co., Ltd.) was applied to the insulated wire in the reference example! ! Immediately after painting, wipe off the paint adhering to the flat part of the wire with a Teflon wiper, then use the insulated wire obtained by heating and melting it as a wire and repeat the same process to insulate the transposed rectangular conductor. Got the wire.

Example 2 Immediately after applying PFA powder coating (manufactured by DuPont Mitsui Fluorochemical Co., Ltd.) to a thickness of approximately 207/I11 on the insulated wire in the reference example, a Teflon die was used to apply paint only at diagonal positions as shown in Figure 2. A transposed rectangular conductor insulated wire was obtained in the same manner except that the coating material remained and the insulated wire obtained by heating and melting this was used as an insulated wire.

Comparative Example 1 A transposed rectangular conductor insulated wire was obtained in the same manner as in the reference example except that molten carnauba wax was applied as a lubricant to a thickness of 3 to 5 nm on the insulated wire to obtain an insulated wire. .

Comparative Example 2 Epoxy powder paint (Jinman Durez ECP2O3) 10
0 parts by weight and 3 parts by weight of polyethylene wax (Hiwax 410P manufactured by Mitsui Petrochemicals) were kneaded together to prepare a powder coating. Using this, a transposed rectangular conductor insulated wire was obtained in exactly the same manner as in the reference example.

The wear resistance (Note 1) of the insulated wires themselves in the above reference examples, working examples, and comparative examples, and the coil winding processability (Note 2) of the transposed conductor insulated wires on each side using these insulated wires. Each was evaluated and the results are shown in Table 1.

(Note 1): Regarding the reciprocating wear of the four corners of the rectangular insulated wire, the number of times it took to reach wear while changing the load was measured, and this was used as a measure of wear resistance.

(Note 2): Take a 1.5 m long sample from the insulated wire, bend it 180 degrees 10 times around a circumferential jig with a diameter of 450 mm, and then calculate the 500ν insulation resistance between the insulated wires. Measurements were made to check for short circuits.

Afterwards, it was disassembled and the damage was examined.

According to the results in the above table, it is clear that the transposed rectangular conductor insulated wire of the example, that is, of the present invention, has a remarkable improvement effect on mechanical strength and winding workability compared to the comparative example, and is used, for example, in transformers. It has been confirmed that this is an excellent product that can respond to miniaturization.

(Effects of the Invention) As is clear from the above description and examples, the present invention provides the above-mentioned transposed rectangular conductor insulated wire, in which a powder coated insulating layer is provided on the conductor as the insulated rectangular conductor, and then a powder coating insulating layer is provided on the conductor. As a result of using an insulated wire having a powder coating layer of a lubricating resin along the longitudinal direction on at least one of the four corners of the cross section of the rectangular conductor, the obtained transposed rectangular conductor insulated wire is In particular, even when the winding diameter during coil winding is relatively small, the friction caused by the contact between the raised strand corner at the strand dislocation section and the adjacent strand corner is significantly alleviated, thereby preventing scratches. occurrence will be drastically reduced.

Since the above-mentioned lubricating coating is applied only partially, the diameter of the stranded wire of the intended transposed rectangular conductor insulated wire is not increased unnecessarily, and this provides a favorable result that further enhances the above-mentioned effects.

[Brief Description of the Drawings] Figs. 1 to 3 are cross-sectional views of examples of insulated wires in the transposed rectangular conductor insulated wire of the present invention, Fig. 4 is a partially cutaway perspective view of the insulated wire of the present invention, and Fig. 5 6 and 6 are cross-sectional views of a conventional transposed rectangular insulated wire, and FIG. 7 is a cross-sectional view of a homogeneous wire. 1.0...Insulated wire, 11...Flat conductor, 12...
- Insulated wire, 13... External common insulating layer, 14... Element wire insulating layer, 15... Powder coating layer (corner). 2 Figure 5 Figure Figure Figure

Claims (1)

[Claims] In a transposed rectangular conductor insulated wire in which a plurality of insulated rectangular conductors are used as strands and are transposed to form a twisted conductor, and a common insulating layer is provided on the outside thereof, a powder is applied on the conductor as the insulated rectangular conductor. After providing a body-coated insulating layer, an insulated wire was used, which was further provided with a powder coating layer made of a lubricating resin along the longitudinal direction at at least one corner of the four corners of the rectangular conductor cross section. A transposed rectangular conductor insulated wire characterized by: