JPH11224821A - Electromagnetic coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic coil capable of improving the workability of winding work, reducing cost and size, and improve space factor. SOLUTION: An electromagnetic coil is composed of an insulated and covered conductor covered with an insulating and covering layer formed by spirally winding a thin material 1 carrying adhesive layers 2 and 3 on both surfaces around a conductor. Since the insulating and covering layer can be stuck to the conductor, the insulating and covering layer is not shifted from the conductor during winding work and stable insulating ability can be maintained. As a result, the insulating and covering layer is less damaged by an instantaneous short-time electromagnetic force. In addition, the electromagnetic coil can be manufactured without the use of an interlayer insulating material through the formation of the insulating and covering layer by sticking the adhesive layers on the thin material 1 to each other. The electromagnetic coil is manufactured by winding the insulated and covered conductor and mutually subjecting the insulating and covering layers to bonding processing, and then, impregnating the wound body with insulating oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated conductor for an oil-filled electromagnetic device and an electromagnetic coil formed thereon.

[0002]

2. Description of the Related Art Conventional electromagnetic devices such as oil-filled transformers and oil-filled reactors having a large capacity may use a rectangular conductor wound with insulating paper. When an electromagnetic coil is formed using the insulated conductor, it is formed using an interlayer insulating material between layers of the coil.

[0005] FIG. 5 is a partial cross-sectional view, and the description will be made based on the sectional view. A conductor 52 on which an insulating coating layer 53 is formed is wound around a winding frame 51 made of a material having high rigidity such as a press board, and an interlayer insulating material 55 is provided for each layer to form an electromagnetic coil. Then, an outer peripheral insulating layer 54 is formed.
An adhesive layer is formed on the surface of the winding frame 51 that contacts the coil, or a porous material having an adhesive layer formed on both surfaces is wound around the winding frame 51, and the winding frame 51 and the winding are bonded to each other. Further, the interlayer insulating material 55 is made of a porous insulating material having an adhesive layer formed on both surfaces. Specifically, cellulose-based kraft insulating paper is widely used as a porous insulating material. Further, since no adhesive layer is formed on the insulating coating layer 53, an adhesive function is added to the interlayer insulating material 55.

[0004]

As described above, in the conventional electromagnetic coil, it is necessary to interpose an interlayer insulating material 55 between layers of the coil and to form an adhesive layer on both surfaces thereof to provide an adhesive function. Therefore, the number of manufacturing steps and the product cost tend to increase. There is also a problem that the size of the electromagnetic coil increases.

[0005] Furthermore, the insulating coating layer 53 of the winding may be displaced from the conductor 52 during the winding operation.
In order to obtain stable insulation reliability, insulation design with high safety factor is required. Accordingly, an object of the present invention is to provide an electromagnetic coil that can improve winding workability, reduce costs and reduce size, and improve the space factor.

[0006]

According to a first aspect of the present invention, there is provided an electromagnetic coil in which a thin sheet material having an adhesive layer formed on both surfaces thereof is spirally wound around a conductor. Characterized by comprising an insulated conductor having an insulative coating layer formed thereon. As described above, since the thin leaf material having the adhesive layers formed on both sides is spirally wound around the conductor, the conductor is formed of the insulated conductor having the insulated coating layer formed on the conductor surface, so that the insulated covering layer can be bonded to the conductor. . For this reason, the insulating coating layer does not shift from the conductor during the winding operation, and stable insulating performance can be maintained. As a result, the insulating coating layer is less likely to be damaged by the electromagnetic force during the instantaneous short period. Further, by bonding the adhesive layers of the thin-leaf material to each other as the insulating coating layer, the electromagnetic coil can be manufactured without using an interlayer insulating material.

According to a second aspect of the present invention, in the first aspect, the thin leaf material is made of a porous material, and the area occupied by the adhesive layer is in the range of 20 to 50%. The area occupied by the adhesive layer affects the adhesive force after bonding, and also affects the impregnating property when the thin-leaf material is impregnated with oil with a porous material therein. Since the content is in the range of 20 to 50%, the balance between the adhesiveness and the impregnation is improved.

According to a third aspect of the present invention, in the electromagnetic coil according to the first or second aspect, winding is performed using an insulated conductor.
Adhesion treatment was performed between the insulating coating layers, and the insulating resin layer was impregnated with insulating oil. As described above, the winding is performed using the insulating coated conductor, the insulating coating layers are bonded to each other, and the insulating resin layer is impregnated with the insulating oil, whereby the electromagnetic coil for the oil-filled electromagnetic device can be manufactured. At this time, the bonding treatment can be performed by the bonding layer formed on the thin leaf material, and the insulating performance can be maintained by the impregnated insulating oil.

According to a fourth aspect of the present invention, in the electromagnetic coil according to the third aspect, only the adhesive layer is interposed between the respective layers formed of the insulated conductor. As described above, since only the adhesive layer is interposed between the layers formed of the insulating covered conductors, the conventionally provided interlayer insulating material becomes unnecessary, and it is possible to save resources and reduce the size and weight. According to a fifth aspect of the present invention, there is provided the electromagnetic coil according to the first, second, third or fourth aspect, wherein the conductor has a substantially rectangular cross-sectional shape and a ratio of the short side to the long side is in a range of 1: 1.5 to 10. Thus, since the cross-sectional shape of the conductor is substantially rectangular and the ratio of the short side to the long side is in the range of 1: 1.5 to 10, the winding property at the time of manufacturing the coil and the bonding condition of the bonding layer are excellent. . That is, when the ratio of the long sides is smaller than 1.5, a twisting phenomenon of the conductor occurs at the time of winding, and it becomes difficult to arrange and wind. When the ratio of the long sides is 10 or more, the adhesiveness of the insulating coating layer deteriorates, and the adhesion between the conductor, the insulating coating layer, and the insulating coating layer deteriorates.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of a thin sheet material of an insulated conductor constituting an electromagnetic coil according to an embodiment of the present invention. In FIG. 1, 1 is a thin-leaf material. Specifically, a porous material or a plastic film is possible. As the porous material, cellulosic kraft paper, plastic fiber, or the like is used. Suitable plastic fibers include polypropylene, polyethylene terephthalate, and polyethylene. Reference numerals 2 and 3 denote adhesive resin layers (adhesive layers), which are formed on both surfaces of the thin leaf material 1. The adhesive resin layers 2 and 3 are formed in a prepreg state.
The thicknesses t1 and t2 are on the order of 5 to 10 microns. As the resin composition of the prepreg, dicyandiamide or an organic acid hydrazide (adipic hydrazide) is used as a latent curing agent for an epoxy resin, 2-methylimidazole or the like is used as a reaction accelerator, and the epoxy resin is dissolved in a solvent such as butanone and applied. After the primary curing, the curing reaction is interrupted and stored, and the final curing treatment is performed after the winding operation.

FIG. 2 is a pattern diagram showing a pattern of the adhesive resin layer formed on the thin leaf material according to the embodiment of the present invention. 2A shows a case of a quadrangular shape, FIG. 2B shows a case of a triangular shape, and FIG. In the figure, reference numeral 21 denotes a thin-leaf material, the configuration of which is the same as that of the thin-leaf material 1 of FIG. 2
Reference numerals 2, 23 and 24 are patterned adhesive resin layers. This configuration is the same as that of the adhesive resin layers 2 and 3 in FIG.
The area occupied by the resin pattern portions of the adhesive resin layers 22, 23, and 24 affects the adhesive strength after bonding, and when the thin leaf material 21 is a porous material, it affects the impregnation property when oil is impregnated in the inside. I do. In other words, when the occupied area of the resin pattern portion is small, the impregnating property is improved, but the adhesiveness is reduced. On the other hand, when the occupied area of the resin pattern portion is large, the adhesive force is improved, but the impregnating property of the oil is reduced and the insulation is reduced. Challenges arise in performance. Therefore, it is necessary to select a place where both are balanced. In this case, the area occupied by the adhesive resin layers 22, 23, and 24 with respect to the surface of the thin leaf material 21 is set to 20 to 50.
%. In addition, care is taken to minimize the area where the resin layer overlaps on the front and back of the resin pattern as much as possible. This is because if they overlap, the impregnating property of the oil will deteriorate.

FIG. 3 is an explanatory view showing a manufacturing process of the insulated conductor according to the embodiment of the present invention. In FIG. 3, reference numerals 32 and 33 denote thin-leaf materials, and their structures are the same as those of the thin-leaf material 1 of FIG. 1 and the thin-leaf material 21 of FIG. By winding thin leaf materials 32 and 33 having an adhesive resin layer formed on both surfaces thereof around the conductor 31 in a spiral shape, an insulated conductor 34 having an insulative coating layer formed on the surface of the conductor 31 is manufactured. The conductor 31 is made of aluminum, copper, or the like, and a plurality of thin leaf materials 32, 33 are wound simultaneously by a machine. The corner portion of the conductor 31 is rounded so that the thin leaf material 32, 33 is not damaged when the thin leaf material 32, 33 is wound. The conductor 31 has a substantially rectangular cross section, and the ratio of the short side B to the long side A is 1: 1.
It is in the range of 5-10. Thereby, the winding property and the bonding condition at the time of manufacturing the coil are excellent. When the ratio of the long side A is smaller than 1.5, a twisting phenomenon of the conductor 31 occurs at the time of winding,
Aligning winding becomes difficult. When the ratio of A on the long side is 10 or more, the adhesion of the insulating coating layer formed by winding the thin leaf materials 32 and 33 becomes poor, and the conductor 31 and the insulating coating layer and the insulating coating layer Adhesion between them becomes worse.

FIG. 4 is a schematic sectional view of an electromagnetic coil according to an embodiment of the present invention. In FIG. 4, reference numeral 46 denotes an insulated conductor, and its configuration is the same as that of the insulated conductor 34 in FIG. As described above, winding is performed using the insulated conductor 46 having the insulative coating layer 43 formed on the surface of the conductor 42, and the insulating coating layers 43 are bonded to each other and then impregnated with insulating oil. Then, an electromagnetic coil is created. Reference numeral 41 denotes a bobbin made of a material having excellent rigidity. The conductor 42 is made of aluminum, copper, or the like as described above. 44 is a coil outer peripheral insulating layer. As the material of the coil outer peripheral insulating layer 44, a thin leaf material having adhesive layers formed on both surfaces is used. Reference numeral 45 denotes an adhesive layer that bonds the insulating coating layers 43 to each other. The adhesive layer 45 is made of the thin material 32, 3 wound around the conductor 42.
3 is formed by an adhesive resin layer formed outside. By performing the heat treatment after the winding, the curing reaction of the adhesive layer 45 is completed, and the adhesive strength is increased.

As described above, according to this embodiment, as shown in FIGS. 1 and 3, the thin leaf material 1 having the adhesive layers 2 and 3 formed on both sides is spirally wound around the conductor 31. Since the conductor 31 is constituted by the insulated conductor 34 having the insulative covering layer formed on the surface thereof,
Can be adhered to. For this reason, the insulating coating layer does not deviate from the conductor 31 during the winding operation, and stable insulating performance can be maintained. As a result, the insulating coating layer is less likely to be damaged by the electromagnetic force during the instantaneous short period. In addition, by bonding the adhesive layers of the thin leaf materials 32 and 33 to each other, the electromagnetic coil can be manufactured without using an interlayer insulating material.

The area occupied by the adhesive layers 2 and 3 affects the adhesive strength after the bonding, and the impregnating property when the thin leaf material 1 is impregnated with oil in a porous material. Since the area occupied by a few is set in the range of 20 to 50%, the balance between the adhesiveness and the impregnation is improved. As shown in FIG. 4, the winding is performed using the insulating coating conductor 46, the insulating coating layers 43 are bonded to each other, and the insulating coating layer 43 is impregnated with the insulating oil. Electromagnetic coils for equipment can be manufactured. At this time, the bonding process is performed on the thin leaf material 1
The insulating performance can be maintained by the impregnated insulating oil.

Further, since only the adhesive layer 45 is interposed between the layers formed by the insulating coated conductors 46, the conventionally provided interlayer insulating material is not required, and resources can be saved and the size and weight can be reduced. Further, since the cross-sectional shape of the conductor 31 is substantially rectangular and the ratio of the short side B to the long side A is in the range of 1: 1.5 to 10, the winding property at the time of manufacturing the coil and the bonding condition of the bonding layers 2 and 3 are good. Is better.

[0017]

Next, an embodiment of the present invention will be described.
Using kraft paper with a thickness of 50 microns as a thin leaf material,
As the adhesive resin layer, a bisphenol-type epoxy resin is used with dicyandiamide as a curing agent, the viscosity is adjusted with butanone, and the adhesive layers are formed on both surfaces by a transfer method using a coating machine. At this time, the thickness of the adhesive resin layer is 5 to 8 microns. FIG. 2A shows a basic pattern diagram at that time, and the occupied area of the adhesive resin layer is 36%. This material is wrapped around the conductor in 3/4 wrap. It is also possible to wind several rolls at a time. The short side of the conductor is 3m
m, the long side is 5 mm.

The insulation-coated conductor formed as described above is 5 m
A specified number of turns is wound around a m-thick press board winding frame, and 10 layers of an 80 μm thick kraft paper having an adhesive resin layer formed on both sides are formed on the outer periphery thereof, and then a heating process is performed. The bobbin and the outer peripheral insulating layer are bonded to each other.

[0019]

According to the electromagnetic coil of the present invention, a thin sheet material having an adhesive layer formed on both surfaces is spirally wound around a conductor to form an insulating coated conductor having an insulating coating layer formed on the conductor surface. Therefore, the insulating coating layer can be bonded to the conductor. For this reason, the insulating coating layer does not shift from the conductor during the winding operation, and stable insulating performance can be maintained. As a result, the insulating coating layer is less likely to be damaged by the electromagnetic force during the instantaneous short period. Further, by bonding the adhesive layers of the thin-leaf material to each other as the insulating coating layer, the electromagnetic coil can be manufactured without using an interlayer insulating material.

According to the second aspect of the present invention, the occupied area of the adhesive layer affects the adhesive strength after bonding, and the impregnating property when the thin leaf material is impregnated with oil with a porous material inside. Since the occupied area is in the range of 20 to 50%, the balance between the adhesiveness and the impregnation is improved. According to the third aspect, the winding is performed using the insulative coated conductor, the insulating coating layers are bonded to each other, and the insulating coating layer is impregnated with the insulating oil, whereby the electromagnetic coil for the oil-filled electromagnetic device can be manufactured. . On this occasion,
The bonding treatment can be performed by the bonding layer formed on the thin leaf material, and the insulating performance can be maintained by the impregnated insulating oil.

According to the fourth aspect of the present invention, since only the adhesive layer is interposed between the layers formed of the insulated conductors, the conventionally provided interlayer insulating material becomes unnecessary, and it is possible to save resources and reduce the size and weight. . According to claim 5, since the cross-sectional shape of the conductor is substantially rectangular and the ratio of the short side to the long side is in the range of 1: 1.5 to 10, the winding property at the time of manufacturing the coil and the bonding condition of the bonding layer are excellent. I have. That is, when the ratio of the long sides is smaller than 1.5, a twisting phenomenon of the conductor occurs at the time of winding, and it becomes difficult to arrange and wind. When the ratio of the long sides is 10 or more, the adhesiveness of the insulating coating layer deteriorates, and the adhesion between the conductor, the insulating coating layer, and the insulating coating layer deteriorates.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a thin-leaf material constituting an electromagnetic coil according to an embodiment of the present invention.

FIG. 2 is a pattern diagram of an adhesive resin layer according to the embodiment of the present invention.

FIG. 3 is an explanatory view showing a process of manufacturing the insulated conductor according to the embodiment of the present invention.

FIG. 4 is a schematic sectional view of the electromagnetic coil according to the embodiment of the present invention.

FIG. 5 is a schematic sectional view of a conventional electromagnetic coil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thin leaf material 2, 3 Adhesive resin layer 21 Thin leaf material 22, 23, 24 Adhesive resin layer 31 Conductor 32, 33 Thin leaf material 34 Insulated covering conductor 41 Reel 42 Conductor 43 Insulating covering layer 44 Outer peripheral insulating layer 45 Adhesive layer 46 Insulating covering Conductor 55 Interlayer insulating material

Continued on the front page (72) Inventor Jiro Yugami 1006 Kadoma Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. An electromagnetic coil comprising an insulating-coated conductor having an insulating coating layer formed on the surface of a conductor by spirally winding a thin leaf material having an adhesive layer formed on both surfaces thereof around a conductor. 2. The electromagnetic coil according to claim 1, wherein the thin leaf material is made of a porous material, and the area occupied by the adhesive layer is in the range of 20 to 50%. 3. The electromagnetic coil according to claim 1, wherein the coil is wound using an insulated conductor, the insulative resin layer is impregnated with insulating oil while the insulative coating layers are bonded to each other. 4. The electromagnetic coil according to claim 3, wherein only an adhesive layer is interposed between the layers formed of the insulated conductor. 5. The conductor according to claim 1, wherein the cross-sectional shape of the conductor is substantially rectangular and the ratio of the short side to the long side is in the range of 1: 1.5 to 10.
Or the electromagnetic coil of 4.