WO2022074900A1 - Fusible insulated wire and self-fusion coil - Google Patents

Abstract

The present invention addresses the problem of providing a fusible insulated wire having a configuration that has excellent insulation performance and is applicable to transformers and coils for consumer appliances.　As a solution, a fusible insulated wire (1) has insulating layers (3a), (3b), (3c) formed at the outer periphery of a conductor (2), and a fusion layer (4) formed at the outer periphery of the insulating layer (3c), the fusion layer (4) is formed by extruding a thermoplastic resin containing a copolyester resin as a main component, a polyester-based hot-melt adhesive and a filler, and the fusion point of the fusion layer (4) is 50 °C to 95 °C (exclusive of 50).

Description

Fusing insulated wires and self-fusing coils

The present invention relates to a fused insulating electric wire and a self-bonded coil.

Conventionally, a fused insulating electric wire having a fused layer composed of an epoxy resin as a main component and a modified ether type polyester resin added, and having improved adhesiveness in a low temperature range of 100 to 150 ° C. is known. (Patent Document 1: Japanese Patent No. 2890280). Further, a fused insulating electric wire having a fused film composed mainly of a copolymerized polyamide resin and having a melting point of 110 to 130 ° C. has been proposed (Patent Document 2: Japanese Patent Application Laid-Open No. 3-08414). ). Then, a fused insulating electric wire having a fused layer formed by extruding a nylon-based hot melt resin containing a polyamide resin as a main component of a modified polyolefin resin and a thermoplastic resin to which calcium carbonate is added at a temperature of 200 ° C. Is known (Patent Document 3: Japanese Unexamined Patent Publication No. 202-134191).

Japanese Patent No. 2890280 Japanese Unexamined Patent Publication No. 3-08414 Japanese Unexamined Patent Publication No. 202-134191

The heat resistant grade required for a general consumer equipment transformer is Class B (allowable temperature 130 ° C) or Class F (allowable temperature 155 ° C) specified in JIS standard (JIS C4003: 2010). Therefore, there is a problem that the insulating material of the transformer is deteriorated by the heat treatment when the fused insulated wire is made into a coil, and there is a problem that the performance of the fused insulated wire is deteriorated. However, it is difficult to further lower the temperature of the fused layer containing an epoxy resin as a main component, and the fused layer containing a polyamide resin is liable to cause pinholes and crazing due to moisture absorption, and its insulating performance is inferior. In the prior art, it was difficult to apply it to the coil of a transformer for consumer equipment with low heat resistance grade and the self-bonding coil for consumer equipment.

INDUSTRIAL APPLICABILITY The present invention has been made in view of the above circumstances, and provides a fusion-sensitive insulated wire having a configuration excellent in insulation performance and having a configuration that can be applied to a coil of a transformer for consumer equipment and a self-bonding coil for consumer equipment. The purpose is to provide.

As an embodiment, the above-mentioned problem is solved by the solution disclosed below.

In the fused insulating electric wire according to the present invention, a fused layer is formed on the outer periphery of an insulating layer formed on the outer periphery of a conductor, and the fused layer is a polyester-based hot melt adhesive containing a copolymerized polyester resin as a main component. It is a structure formed by extruding a thermoplastic resin to which an agent and a filler are added, and is characterized in that the melting point of the fused layer is more than 50 ° C. and 95 ° C. or lower.

According to this configuration, the fused layer formed by extruding a thermoplastic resin containing a copolymerized polyester resin formed on the outer periphery of the insulating layer as a main component and having a filler added thereof provides an excellent insulating performance. Moreover, the melting point of the fused layer made of a thermoplastic resin containing a copolymerized polyester resin as a main component and a polyester-based hot melt adhesive added is set to a coil of a transformer for consumer equipment and a self-bonded coil for consumer equipment. Can be configured to be applicable. That is, the fused layer can be prevented from being self-fused by the temperature during transportation or the temperature during storage while maintaining good adhesiveness. Further, the fused layer can prevent deterioration of the insulating material of the transformer to which the fused insulated wire is applied while maintaining good adhesiveness.

The melting point of the fused layer is preferably more than 60 ° C and less than 92 ° C. The melting point of the fused layer is more preferably more than 68 ° C and less than 91 ° C. As an example, the insulating layer is formed by wrapping an insulating tape. This makes it easy to reduce the outer diameter while improving the insulation. It is more preferable that the insulating layer has three layers. As an example, the copolymerized polyester resin is polyethylene terephthalate, and the insulating property is further enhanced. As an example, the filler is calcium carbonate, which further enhances the adhesion between the insulating layer and the fused layer. As an example, the thickness of one side of the fusion layer in the radial direction is 20 to 40 μm, and the outer diameter may be suitable for a coil of a transformer for a small consumer device or a self-bonding coil for a small consumer device. It can be done easily.

In the self-bonding coil according to the present invention, a fusion layer is formed on the outer periphery of an insulating layer formed on the outer periphery of a conductor, and the fusion layer is a polyester hot melt adhesive containing a copolymerized polyester resin as a main component. And the fused insulating wire formed by extruding the thermoplastic resin to which the filler is added is spirally wound, and the adjacent fused layers in the fused insulated wire are fused to each other. It is characterized in that the melting point of the fused layer is more than 50 ° C. and 95 ° C. or lower.

According to this configuration, the fused layer in the fused insulated wire can be a self-bonding coil made of a fused insulated wire having excellent insulating performance by preventing deterioration of the insulating layer while maintaining good adhesiveness. .. The fused layer in the fused insulated wire constituting the self-bonded coil can prevent the self-bonded coil from unraveling due to the temperature during transportation and the temperature during storage while maintaining good adhesiveness.

The melting point of the fused layer is preferably more than 60 ° C and less than 92 ° C. The melting point of the fused layer is more preferably more than 68 ° C and less than 91 ° C. As an example, the copolymerized polyester resin is polyethylene terephthalate, and the filler is calcium carbonate. As an example, the thickness of one side in the radial direction of the fused layer in the fused insulated wire is 20 to 40 μm. As a result, a high-performance and compact self-bonding coil can be realized.

According to the present invention, it is possible to realize a fusion-sensitive insulated wire having a configuration that is excellent in insulation performance and that can be applied to a coil of a transformer for consumer equipment or a self-bonding coil.

FIG. 1 is a structural diagram schematically showing the structure of a fused insulated wire according to an embodiment of the present invention. FIG. 2 is a schematic external view showing an example of a self-bonding coil to which the fusion-sensitive insulated wire shown in FIG. 1 is applied.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The fused insulated wire 1 of the present embodiment is applied to, for example, a coil of a transformer for consumer equipment. It is also applied to, for example, a self-bonding coil. In all the drawings for explaining the embodiment, the members having the same function may be designated by the same reference numerals, and the repeated description thereof may be omitted.

(Fusionable insulated wire)
First, the fused insulated wire 1 and the manufacturing method thereof according to the present embodiment will be described below with reference to FIG.

The fused insulating electric wire 1 shown in FIG. 1 includes a conductor 2, a first insulating layer 3a formed on the outer periphery of the conductor 2, a second insulating layer 3b formed on the outer periphery of the first insulating layer 3a, and a first layer. 2 It is configured to have a third insulating layer 3c formed on the outer periphery of the insulating layer 3b and a fusion layer 4 formed on the outer periphery of the third insulating layer 3c. That is, the insulating layer 3 is formed of three layers on the outer periphery of the conductor 2, and the fusion layer 4 is formed on the outer periphery thereof.

The conductor 2 may be any conductive material, but is preferably a conductive conductor that can be soldered. For example, a composite material such as copper or a copper alloy, aluminum or an aluminum alloy, or copper clad aluminum, or a metal having excellent solderability may be plated on these materials. When it is not easy to solder the conductor itself, it is preferable to provide a metal having excellent solderability by plating or the like. Metals with excellent solderability include tin, solder, nickel, gold, silver, copper, palladium, or alloys of these materials.

The conductor 2 can be a single wire or a stranded conductor. In the case of stranded wire, a lubricant or an antioxidant may be applied to the surface of each conductor wire. The lubricant improves the slipperiness of the conductor wire, which makes the stranded wire easier, and also makes the individual conductor wire slippery when coiling with the finally obtained insulated wire. The linearity can be made easier. The antioxidant has an effect of preventing the oxidation of the conductor wire, and can prevent the oxidation that may occur at the time of twisting or winding the tape. Further, the single wire or the stranded wire constituting the conductor 2 may be provided with an insulating film in advance. Examples of the insulating film include an enamel film and an oxide film. As the insulating film, a urethane-based or polyester-based enamel film that does not interfere with soldering is preferable. In particular, when it is desired to reduce the high frequency loss due to the skin effect, it is preferable to use a conductor wire having an insulating film arranged in advance.

As an example, a copper wire having a diameter of 4.5 mm is drawn to a diameter of 0.5 mm to form a round conductor 2 having a circular or elliptical cross section. As a configuration other than the above, a stranded wire obtained by twisting a plurality of strands and having a cross section similar to a round shape such as a circle or an ellipse can be used as the conductor 2. When the conductor 2 is a stranded wire, it is preferable because the conductor 2 is composed of seven strands so that the cross section can be made into a shape closer to a round shape such as a circle or an ellipse. In some cases, the conductor 2 is a stranded wire composed of five or more strands.

The insulating layer 3 has one or more insulating layers. The insulating layer 3 is preferably composed of two or more insulating layers. Examples of the material of the insulating layer 3 include polyethylene naphthalate (PEN), polyimide (PI), polyphenylene sulfide (PPS), ethylene-ethylene tetrafluoroethylene copolymer (ETFE), and ethylene tetrafluoride-propylene hexafluoride. Examples thereof include a polymer (FEP), a fluorinated resin copolymer (perfluoroalkoxy alkane resin: PFA), polyetheretherketone (PEEK), polyethylene terephthalate (PET), polyamide (PA) and the like. The material of the insulating layer 3 is appropriately set according to the application.

The insulating layer 3 is configured by tape winding insulation with insulating tape as an example. In this case, the thickness of the insulating tape is preferably, for example, 4 μm or more and 25 μm or less. Further, the width of the insulating tape in this case is preferably, for example, 2 mm or more and 20 mm or less. The thickness and width of the insulating tape are appropriately set according to the application, and the thickness and width of each insulating tape may be the same when two or more layers of tape are wound and insulated. May vary in thickness and width.

As an example, it is preferable that the insulating layer 3 is tape-wound with two or more layers by insulating tape. Of the plurality of insulating tapes to be tape-wound and insulated, at least the overlapping portion of the insulating tapes is an adhesive layer, and both are adhered to each other. The adhesive layer is provided on at least one insulating tape among the plurality of insulating tapes. Examples of the constituent material of the adhesive layer include an adhesive material that is solidified by heat, ionizing radiation, or the like. The adhesive material to be bonded and solidified by heat is a heat-bondable material, and examples thereof include heat-bonded adhesive materials such as polyester-based, acrylic-based, and epoxy-based materials. For example, examples of the adhesive material that is adhered and solidified by ionizing radiation such as ultraviolet rays include an ionizing radiation adhesive material such as acrylic and epoxy. It is preferable that each insulating tape is spirally wound in the opposite direction to each other. The winding form of each insulating tape is appropriately set according to the application.

In particular, when the insulating layer 3 is configured to be tape-wound with three or more layers by insulating tape, high insulating properties can be realized. This configuration is certified as an insulated wire that meets safety standards such as IEC60950, and can be used as a wire for coils such as an isolation transformer and an IH heater. When a fusion-sensitive insulated wire 1 having a structure in which the insulating layer 3 is tape-wound with three or more layers with insulating tape is used for the transformer coil, the primary side and the secondary side can be more reliably insulated. .. As an example, as shown in FIG. 1, when the first insulating layer 3a, the second insulating layer 3b, and the third insulating layer 3c are provided, an insulating tape is wrapped around the outer periphery of the conductor 2 to form the first insulating layer 3a. , The insulating tape is wrapped around the outer periphery of the first insulating layer 3a via the adhesive layer to form the second insulating layer 3b, and the insulating tape is wrapped around the outer periphery of the second insulating layer 3b via the adhesive layer. To form the third insulating layer 3c. The thickness of the insulating layer 3 on one side in the radial direction is, for example, 10 to 300 μm.

As a configuration other than the above, for example, when the insulating layer 3 is formed by extrusion processing, a thermoplastic resin is extruded on the outer periphery of the conductor 2 to form the first insulating layer 3a, and the thermoplastic resin is formed on the outer periphery of the first insulating layer 3a. The resin can be extruded to form the second insulating layer 3b, and the thermoplastic resin can be extruded on the outer periphery of the second insulating layer 3b to form the third insulating layer 3c.

The fused layer 4 is formed on the outer periphery of the third insulating layer 3c and is self-fused by heating. The fused layer 4 is formed by extruding a thermoplastic resin containing a copolymerized polyester resin as a main component and a polyester-based hot melt adhesive and a filler added. The temperature of the heating unit in the extruder is set to 170 to 250 ° C. as an example. In this embodiment, the melting point of the fused layer 4 is more than 60 ° C and less than 92 ° C. The thickness of the fused layer 4 on one side in the radial direction is, for example, 10 to 50 μm. As an example, the copolymerized polyester resin is polyethylene terephthalate, and the filler is calcium carbonate (CaCO ₃ ).

(Self-bonding coil)
Subsequently, the self-bonding coil 10 and the manufacturing method thereof according to the present embodiment will be described below with reference to FIG.

The self-bonding coil 10 shown in FIG. 2 is composed of the fused insulating electric wire 1 of the above-described embodiment. As an example, the mandrel rod is wound around a mandrel rod (winding jig) having a diameter 5 to 20 times the diameter of the conductor 2 while keeping the fused layer 4 and the fused layer 4 in close contact with each other, and then the mandrel rod is removed. The coil is heated by standing in a constant temperature bath set to a temperature higher than the melting point of the fusion layer 4 at 10 to 30 ° C. for 3 to 10 minutes to form a helical self-bonding coil 10 having an air core. The temperature of the constant temperature bath is, for example, 110 to 130 ° C. As a configuration other than the above, as the heating means, a tunnel furnace, a batch furnace, a hot air blower, or other known heating means can be applied.

In the example shown in FIG. 2, in the self-bonding coil 10, the tip portion 10a and the tip portion 10b of the fused insulating electric wire 1 are immersed in a solder bath, and the conductor 2 is solder-plated. When the fused insulating electric wire 1 is heated by a solder bath or a soldering iron, the insulating layer 3 and the fused layer 4 are melted and the conductor 2 can be easily solder-plated. It should be noted that the coil is not limited to the round self-bonding coil 10 as shown in FIG. 2, and the spiral coil has various shapes such as a record winding coil, a pancake coil, a square coil, and a conical coil. It is possible to apply to.

Subsequently, each embodiment of the self-bonding coil 10 according to the present embodiment will be described below.

The manufacturing method of the fused insulating electric wire 1 is as described above. The conductor 2 is a copper wire having a diameter of 0.5 mm, the thickness of one side of the first insulating layer 3a in the radial direction is 40 μm, the thickness of one side of the second insulating layer 3b in the radial direction is 30 μm, and the thickness of the third insulating layer 3b is 30 μm. The thickness of the layer 3c on one side in the radial direction is 20 μm, and the thickness of the fused layer 4 on one side in the radial direction is 30 μm. When the fused layer 4 was formed, the melting point of the fused layer 4 was adjusted to be lowered by increasing the compatibility between the copolymerized polyester resin and the polyester-based hot melt adhesive. Then, the self-bonding coils 10 of Examples 1 to 10 were manufactured according to the above-mentioned method for manufacturing the self-bonding coil 10. The number of samples is 20 each. In Example 1, the melting point of the fused layer is 52.3 ° C, in Example 2 the melting point of the fused layer is 57.4 ° C, and in Example 3 the melting point of the fused layer is 61.7 ° C. In Example 4, the melting point of the fused layer is 68.0 ° C., in Example 5 the melting point of the fused layer is 70.1 ° C, and in Example 6 the melting point of the fused layer is 74.0 ° C. In Example 7, the melting point of the fused layer is 81.0 ° C, in Example 8 the melting point of the fused layer is 83.8 ° C, and in Example 9 the melting point of the fused layer is 91.2 ° C. In Example 10, the melting point of the fused layer is 95.0 ° C. Here, it was confirmed that the melting point was about 100 ° C. (99 to 105 ° C.) when only the thermoplastic adhesive made of the copolymerized polyester resin was used. These melting points were measured according to the softening point test method for JIS K 6863-1994 hot melt adhesives.

The evaluation conditions for the adhesive strength of each sample are as follows. The adhesive strength of the fused layer is determined by pulling the adhesive strength of the fused layer in the direction in which the tip on one side and the tip on the other side are opposite to each other in the wire drawing direction of the conductor in each sample at room temperature using a tensile tester. The peel strength required for the fused layers adjacent to each other to peel off was measured. The evaluation criteria for adhesive strength are as follows: A rank is when the average peel strength is 3N or more, B rank is when the average peel strength is 2N or more and less than 3N, and C rank is when the average peel strength is 1N or more and less than 2N. And said.

The evaluation conditions for the storage stability of each sample are as follows. For storage stability, each sample was allowed to stand at a predetermined storage temperature for 240 hours using a constant temperature bath, then taken out, and whether or not the fused layer had tack (stickiness) was checked by contact with the fingertips. The evaluation criteria for storage stability were A rank for no tack at a storage temperature of 60 ° C, B rank for no tack at a storage temperature of 50 ° C, and C rank for no tack at a storage temperature of 40 ° C. Here, the temperature of 60 ° C. assumes the heat-resistant temperature required for mailing, and the temperature of 40 ° C. assumes the heat-resistant temperature required for storage.

Table 1 shows the evaluation results of the adhesive strength and storage stability of each sample.

As shown in Table 1, in Examples 1 and 2, the adhesive strength was A rank and the storage stability was C rank. In Examples 2 to 9, the adhesive strength was A rank or B rank or higher, and the storage stability was A rank or B rank or higher. Further, in Example 10, the adhesive strength was C rank and the storage stability was A rank. Further, in the conventional technique (comparative example) in which the melting point of the fused layer is about 100 ° C., the adhesive strength is less than 1N, which is insufficient for a self-bonding coil. Examples 1 to 10 were found to have excellent properties in both adhesive strength and storage stability as compared with the prior art.

The meltable insulated wire of the above-described embodiment can be applied not only to a self-bondable coil but also to a coil of a transformer for consumer equipment and a known coil or inductor for electronic equipment.

The present invention is not limited to the examples described above, and various modifications can be made without departing from the present invention.

Claims (6)

1. A fusion layer is formed on the outer periphery of the insulating layer formed on the outer periphery of the conductor, and the fusion layer is a thermoplastic resin containing a copolymerized polyester resin as a main component and a polyester hot melt adhesive and a filler added. A fused insulating electric wire having a structure formed by extrusion and having a melting point of more than 50 ° C and a melting point of 95 ° C or lower.
2. The fused insulating electric wire according to claim 1, wherein the copolymerized polyester resin is polyethylene terephthalate and the filler is calcium carbonate.
3. The fused insulating electric wire according to claim 1 or 2, wherein the melting point of the fused layer is more than 60 ° C and less than 92 ° C.
4. A fusion layer is formed on the outer periphery of the insulating layer formed on the outer periphery of the conductor, and the fusion layer is a thermoplastic resin containing a copolymerized polyester resin as a main component and a polyester hot melt adhesive and a filler added. The fused insulating electric wire formed by extrusion is spirally wound, and the adjacent fused layers in the fused insulated wire are fused to each other, and the melting point of the fused layer is formed. Is a self-bonding coil characterized by being above 50 ° C and below 95 ° C.
5. The self-bonding coil according to claim 4, wherein the copolymerized polyester resin is polyethylene terephthalate and the filler is calcium carbonate.
6. The self-bonding coil according to claim 4 or 5, wherein the melting layer has a melting point of more than 60 ° C and less than 92 ° C.
   
   

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