JP4360566B2 - Insulated wire and method of manufacturing coil using the same - Google Patents

Description

【００３０】
表１の結果より明らかなように、実施例１〜７で得られた絶縁電線は耐摩耗性が良好でコイル加工性に優れ、かつ、コイルを粉体エポキシ樹脂系ワニスで処理したときにワニスが表面に均一に付着しており、ワニス塗膜の接着力も高かった。本発明方法により得られたコイルはコイル巻きでの被膜損傷が少なく、かつ、電線同士がワニスで十分に固着されていた。
これに対し比較例１及び２の絶縁電線は、コイルの含浸ワニス処理において表面がワニスをはじく現象がみられ、ワニス塗膜の接着力が低かった。比較例３の絶縁電線では部分的にワニスがはじかれずに付着したが、接着力は実施例のものより低く、十分ではなかった。また、比較例３で用いた減摩剤塗料Ｎo.５は安定性が悪く、作製後７日で沈殿が生じた。
【００３１】
【発明の効果】
本発明の絶縁電線は、厳しいコイル加工条件にも耐えうる自己潤滑性を有し、かつ、含浸ワニス塗着性に優れる。したがって本発明の絶縁電線は、従来含浸ワニス処理が不十分ないしは困難であった自己潤滑性のエナメル線の含浸ワニス処理を可能にする。したがって、このような絶縁電線を用いてコイル巻き後、含浸ワニス処理を行うコイル加工を行えば、耐摩耗性、コイル加工性に優れ、ワニスによる固着性の優れたコイルが得られる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an insulated wire used as a coil of a motor or a generator. More particularly, the present invention relates to an insulated wire having good coil workability and impregnating varnish coating properties, and a method for producing a coil using the same.
[0002]
[Prior art]
Insulated wires coated with an electrical insulator are used in large quantities for applications of coils incorporated in various electrical devices. In recent years, speeding up and rationalization in the coil winding process of this insulated wire have been promoted, and the coil winding operation has been shifted from conventional manual winding to processing by an automatic coil winding machine.
However, when this automatic coil winding process is performed, a large tension is applied to the insulated wire and the work is performed at a high speed, so that the stress of the coating is large, and the insulated wire is apt to be damaged. For this reason, coil insulation defects such as layer shorts and ground defects tend to occur.
[0003]
Also, when forming the coil, increasing the space factor of the insulated wire in the status lot in the coil as much as possible results in downsizing of the entire device and cost reduction. It is requested. In recent years, with this reduction in diameter, there has been a demand for deferring or increasing the conductor diameter with the intention of increasing the power of equipment, and it has become necessary to reduce the thickness of the insulating coating.
However, the thinning of the insulating coating increases the frequency of coating damage during the coil processing (coil winding operation and insertion into the status lot), and increases the incidence of coil insulation failure.
In order to solve the above problems, it is conceivable to reduce the friction coefficient between the electric wires or the objects (metal rod, interphase paper, etc.) in contact with the electric wires and to improve the coating strength. The lower the coefficient of friction, the easier the coil winding work, and the stronger the coating strength, the less damage is generated during coil processing.
[0004]
Conventional means for reducing the friction coefficient include a method of applying a lubricant to the surface of an electric wire, or a method of applying and baking a lubricant in an insulating paint.
As a technique for improving the film strength, an insulated wire coated with a polyamide-imide paint and baked is usually used. This wire has high mechanical strength and excellent wear resistance compared to other resins (polyester, polyurethane, polyesterimide, polyesteramideimide, polyimide), so it is often used when the coil processing conditions are severe. It was.
[0005]
Accordingly, when coil winding is performed under severe conditions, enameled wires having a coating film obtained by applying and baking the above-described polyamide-imide paint as an insulating layer and further having a surface layer subjected to lubrication are widely used. In recent years, this lubrication treatment can be expected to greatly reduce the coefficient of friction and improve the wear resistance. Therefore, a lubricating paint (friction agent) in which wax and a thermosetting resin are dispersed in water has come to be used. I came.
[0006]
However, the enameled wire using this lubricant has an impregnated varnish treatment (was enameled wire after winding the enameled wire in a coil shape, because the wax and thermosetting resin are baked on the surface of the wire. In order to integrate the varnish, there is a problem that depending on the type of varnish, the surface of the electric wire repels the varnish. When the impregnating varnish treatment is performed, the wires will not be separated by vibration of the motor, etc., and the enameled wire scratches caused by coil processing can be sealed, but if the wire surface repels the varnish, the adhesion to the enameled wire will decrease. As a result, the wires are easily broken and the flaws on the enameled wire are difficult to seal, which tends to cause insulation failure. In addition, in the manufacture of motors and generators, the wire is scratched during the process of pushing the wire into the slot. However, if the wire is not firmly attached to the surface of the varnish, the scratch cannot be sealed, resulting in many pinholes. It becomes. Such a wire surface repels varnish, which is a problem in the manufacture of motors and generators.
This problem occurs when either a solvent varnish or a solventless varnish is used, but a solventless powder epoxy resin varnish is particularly easily repelled. It has also been found that this phenomenon varies depending on the baking conditions of the lubricant on the enamel wire. Generally, the higher the temperature and the higher the speed, the easier the surface of the electric wire will repel the varnish. Therefore, it has been difficult to provide a surface of the electric wire that is lubricated by a highly productive method and does not repel varnish.
[0007]
[Problems to be solved by the invention]
Therefore, the object of the present invention is to have self-lubricating properties, excellent coil workability and high impregnating varnish coatability, and can be coiled under severe conditions even if the insulating coating is thinned, and is well impregnated. It is providing the insulated wire which can perform a varnish process.
Moreover, the objective of this invention is related with the manufacturing method of the coil which can perform an impregnation varnish process favorably using a self-lubricating insulated wire.
[0008]
[Means for Solving the Problems]
As a result of intensive studies in view of the above problems, the present inventors have obtained a varnish having improved impregnating varnish coatability by containing a predetermined amount of a rosin-based resin or a maleic acid-based resin in a lubricant used for surface lubrication. The present inventors have found that an insulated wire having a non-repellent surface can be obtained, and have reached the present invention based on this finding.
That is, the present invention
(1) At least one insulating layer formed by applying and baking an insulating paint on the conductor, and a lubricant layer formed by applying and baking a lubricant to the surface layer of the coating layer having the insulating layer. The anti-friction agent contains a wax and a thermosetting resin, and the rosin resin or maleic acid with respect to 100 parts by weight of the anti-friction agent solid content excluding the rosin resin and the maleic acid resin. Insulated wires comprising 3 to 20 parts by weight of a resin,
(2) The insulated paint forming the insulating layer comprises a polyamide-imide resin, and the insulated wire according to (1) and (3) (1) are coiled. The present invention provides a method for producing a coil, characterized by performing an impregnation varnish treatment.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The insulated wire of the present invention has at least one insulating layer and a lubricant layer on the conductor. There is no restriction | limiting in particular as a conductor, The thing used normally can be mention | raise | lifted. In the present invention, the insulating layer can be formed by applying and baking an insulating paint by a usual method. As the insulating paint, those usually used can be used. Specifically, for example, it comprises one or more selected from polyvinyl formal, polyurethane, polyester, polyesterimide, polyesteramideimide, polyamideimide, polyimide and the like. The insulating layer may be a single layer or a combination of two or more kinds of paints.
[0010]
In the present invention, in order to improve the coating strength of the insulating layer, it is preferable to use a polyamide-imide resin paint as the insulating paint. The base resin of the polyamideimide resin coating at this time is not particularly limited. For example, the base resin obtained by directly reacting tricarboxylic acid anhydride and diisocyanate in a polar solvent, or tricarboxylic acid in a polar solvent. A product obtained by first reacting a diamine with an acid anhydride, first introducing an imide bond, and then amidating with a diisocyanate can be used.
[0011]
As the tricarboxylic acid anhydride used for preparing the resin, trimellitic acid anhydride is usually used. In this case, a part of the tricarboxylic acid anhydride may be replaced with a tetracarboxylic acid anhydride for the reaction. Examples of the tetracarboxylic acid anhydride used here include pyromellitic dianhydride and 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride. In addition, a part of the tricarboxylic acid anhydride may be replaced with another acid or acid anhydride such as trimellitic acid, isophthalic acid, terephthalic acid, or the like. On the other hand, examples of the diisocyanates to be reacted with the tricarboxylic acid anhydride include aromatic diisocyanates such as 4,4′-diphenylmethane diisocyanate and tolylene diisocyanate, and examples of the diamine include m-phenylenediamine and 4,4 ′. -Aromatic diamines such as diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, and 4,4′-diaminobenzophenone. As the polar solvent, N-methyl-2-pyrrolidone can be preferably used.
[0012]
Moreover, in order to improve the adhesiveness of an insulating layer and a conductor, this polyamidoimide type resin coating material can also contain a trialkylamine and alkoxylated melamine resin. The trialkylamine is preferably a lower alkyl trialkylamine such as trimethylamine, triethylamine, tripropylamine or tributylamine. Among these, trimethylamine and triethylamine are most preferable in terms of flexibility and adhesion. In addition, as the alkoxylated melamine resin, for example, a melamine resin substituted with a lower alkoxy group such as a butoxylated melamine resin or a methoxylated melamine resin can be used, and a methoxylated melamine resin is preferable in terms of compatibility of the resin.
An insulating layer with a high adhesion to such a conductor is used as the lowermost layer, an insulating layer of another composition is formed, or an intermediate layer is formed that prevents external stress from being transmitted to the lowermost layer. A layer may be provided.
[0013]
In the insulated wire of the present invention, the thickness of the insulating layer is not particularly limited, but is usually 20 to 40 μm, preferably 25 to 35 μm.
In addition, the baking treatment of the insulating paint is obvious to those skilled in the art, and the conditions such as temperature can be appropriately determined according to the type of insulating paint used, the thickness of the insulating layer, etc. When used, a baking temperature of 400 to 500 ° C. can be adopted as a preferable condition.
[0014]
The insulated wire of the present invention has a lubricant layer on the surface layer of the covering layer having at least one insulating layer. This lubricant layer can be formed by applying and baking a lubricant containing a rosin resin or a maleic resin together with wax, thermosetting resin, or the like.
Lubricant preparations is usually carried out by mixing the alkaline aqueous solution in the aqueous dispersion and a thermosetting resin of the wax, in the present invention further mixing rosin resin or maleic acid-based resins such as an alcohol solution or an aqueous alkaline solution To do.
[0015]
In this anti-friction agent, the wax usually used for the anti-friction agent can be used without particular limitation, for example, natural wax such as carnauba wax, beeswax, cadilla wax, rice wax, paraffin wax, polyethylene wax, montan wax, etc. Examples include synthetic waxes. From the viewpoint of wear resistance and slipperiness of the insulated wire, it is preferable to use a wax having a hardness as high as possible. The ratio of the wax to the thermosetting resin in the lubricant is not particularly limited, but the wax / resin is preferably 30/70 to 70/30 by weight.
The thermosetting resin has an action of fixing the wax when the lubricant is baked. In the present invention, a thermosetting resin usually used as a lubricant can be used. For example, shellac resin and phenol resin can be preferably used.
[0016]
In the present invention, a rosin resin or a maleic resin is further added to the lubricant. Examples of the rosin resin or maleic resin that can be used in the present invention include rosin, rosin-modified maleic resin, and styrene-maleic resin. The rosin resin and maleic acid resin preferably have an acid value of 80 or more. If the acid value is too low, the resin becomes insoluble in alcohol, and an alkaline aqueous solution cannot be prepared, which may make it difficult to mix with a lubricant.
In the present invention, the addition amount of the rosin resin or maleic resin is usually 3 to 20 parts by weight, preferably 100 parts by weight of the solid content of a normal lubricant excluding the rosin resin and maleic resin. 5 to 15 parts by weight. If the rosin resin or maleic resin is less than 3 parts by weight, the impregnating varnish coatability is not sufficiently improved, and if it exceeds 20 parts by weight, the paint stability of the lubricant is impaired.
In the present invention, when a predetermined amount of rosin resin or maleic resin is added to the lubricant layer, the curing of the thermosetting resin of the lubricant itself is suppressed, and the adhesion of the lubricant layer is moderately weakened. It is conceivable that an insulated wire having a smooth surface can be obtained, which has high coatability for impregnating varnish and can be applied well with powder type varnish in the impregnating varnish treatment.
[0017]
In the insulated wire of the present invention, the thickness of the lubricant layer is not particularly limited, but is preferably 1 to 2 μm. The total film thickness is not particularly limited, but is preferably 25 to 35 μm.
The baking treatment of the lubricant paint is also obvious to those skilled in the art, and conditions such as temperature are appropriately determined according to the linear velocity and the like, but are preferably performed at a temperature in the range of 300 to 500 ° C.
[0018]
In the coil manufacturing method of the present invention, the coil winding method is not particularly limited, and can be performed by a normal automatic coil winding process or the like. Since the insulated wire of the present invention used in the method of the present invention is excellent in coil workability, automatic coil winding processing with severe conditions is also possible. The shape and type of the coil are not particularly limited.
When the insulated wire of the present invention is treated with an impregnating varnish, it can be satisfactorily performed by either a method using a liquid varnish or a method using a powder varnish. For example, even when a powder epoxy resin varnish that has been easily repelled by a lubricated electric wire is used, there is no problem such that the electric wire is sufficiently fixed and the wire is separated.
[0019]
【Example】
Next, the present invention will be described in more detail based on examples.
In each example and comparative example, the insulating paint was baked at 500 ° C., and the lubricant coating was baked at 500 ° C.
Example 1
Commercially available anti-friction coating TEC9601 (trade name, manufactured by Toshiba Chemical Co., consisting of carnauba wax and shellac resin) and rosin-modified maleic acid resin (acid value 300, Marquide 33 (trade name, manufactured by Arakawa Chemical Industries)) 5 parts by weight was added to 100 parts by weight of the total solid content of TEC 9601 and stirred at room temperature to obtain a lubricant coating No. 1.
A commercially available polyamideimide resin coating HI406 (trade name, manufactured by Hitachi Chemical Co., Ltd.) is applied and baked several times on a 1.0 mmφ copper wire using a vertical hot air baking machine with a furnace length of 8 m, and a lower insulating layer with a film thickness of 30 μm. Formed. On this, the lubricant paint No. 1 was applied and baked once to form a lubricant film layer having a film thickness of 2.0 μm to obtain an insulated wire having a total film thickness of 32 μm.
[0020]
Example 2
A lubricant coating No. 1 ′ was obtained in exactly the same manner as in Example 1 except that the amount of the rosin-modified maleic resin added was 10 parts by weight with respect to 100 parts by weight of the total solid content of TEC9601.
In the same manner as in Example 1, an insulating layer was formed on a copper wire, and a lubricant coating No. 1 ′ was applied and baked once thereon, and the total film thickness was 32 μm (insulating layer 30 μm, lubricant layer 2. 0 μm) of insulated wire was obtained.
[0021]
Example 3
Implemented except that 5 parts by weight of styrene maleic acid resin (acid value 200, Alastor 700 (trade name, manufactured by Arakawa Chemical Industries)) was used in place of rosin-modified maleic resin with respect to 100 parts by weight of the total solid content of TEC9601. A lubricant coating No. 2 was obtained in exactly the same manner as in Example 1.
In the same manner as in Example 1, an insulating layer was formed on the copper wire, and the lubricant coating No. 2 was applied and baked once thereon, and the total coating thickness was 32 μm (insulating layer 30 μm, lubricant layer 2.0 μm). ) Insulated wire was obtained.
[0022]
Example 4
In place of the rosin-modified maleic resin, the same styrene maleic resin as in Example 3 was used in the same manner as in Example 1 except that 10 parts by weight of 100 parts by weight of the total solid content of TEC 9601 was used. 2 'was obtained.
In the same manner as in Example 1, an insulating layer was formed on a copper wire, and a lubricant coating No. 2 ′ was applied and baked once thereon, and the total film thickness was 32 μm (insulating layer 30 μm, lubricant layer 2. 0 μm) of insulated wire was obtained.
[0023]
Example 5
A rosin resin (Chinese rosin (trade name, manufactured by Arakawa Chemical Industry Co., Ltd.)) instead of the rosin-modified maleic resin was used in exactly the same manner as in Example 1 except that 5 parts by weight was used with respect to 100 parts by weight of the total solid content of TEC9601. Thus, a lubricant coating No. 3 was obtained.
In the same manner as in Example 1, an insulating layer was formed on the copper wire, and the lubricant coating No. 3 was applied and baked once thereon, and the total film thickness was 32 μm (insulating layer 30 μm, lubricant layer 2.0 μm). ) Insulated wire was obtained.
[0024]
Example 6
The lubricant coating No. 3 ′ was used in exactly the same manner as in Example 1 except that 10 parts by weight of the same rosin resin as in Example 5 was used instead of rosin-modified maleic acid resin based on 100 parts by weight of the total solid content of TEC9601. Got.
In the same manner as in Example 1, an insulating layer was formed on the copper wire, and the lubricant coating No. 3 ′ was applied and baked once thereon, and the total film thickness was 32 μm (insulating layer 30 μm, lubricant layer 2. 0 μm) of insulated wire was obtained.
[0025]
Example 7
A commercially available improved polyamideimide resin paint HI406A (trade name, manufactured by Hitachi Chemical Co., Ltd.) is applied and baked several times on a 1.0 mmφ copper wire using a vertical hot air baking machine having a furnace length of 8 m, and the film thickness is 30 μm. The lower insulating layer was formed. On top of this, the same lubricant coating No. 1 as in Example 1 was applied and baked once to form a lubricant layer having a film thickness of 2.0 μm to obtain an insulated wire having a total film thickness of 32 μm.
[0026]
Comparative Example 1
In the same manner as in Example 1, an insulating layer was formed on a copper wire, and a commercially available anti-friction coating TEC9601 was applied and baked once thereon to a total film thickness of 32 μm (insulating layer 30 μm, anti-friction agent layer 2.0 μm). ) Insulated wire was obtained.
Comparative Example 2
2 parts by weight of the same rosin-modified maleic acid resin as used in Example 1 was added to TEC 9601 based on 100 parts by weight of the total solid content of TEC 9601, and the mixture was stirred at room temperature to give the lubricant coating No. .4 was obtained.
In the same manner as in Example 1, an insulating layer was formed on the copper wire, and the lubricant coating No. 4 was applied and baked once thereon, and the total film thickness was 32 μm (insulating layer 30 μm, lubricant layer 2.0 μm). ) Insulated wire was obtained.
[0027]
Comparative Example 3
25 parts by weight of the same rosin-modified maleic acid resin as used in Example 1 was added to TEC 9601 in 100 parts by weight of the total solid content of TEC 9601 and stirred at room temperature to reduce the lubricant coating No. .5 was obtained.
In the same manner as in Example 1, an insulating layer was formed on the copper wire, and the lubricant coating No. 5 was applied and baked once thereon, and the total coating thickness was 32 μm (insulating layer 30 μm, lubricant layer 2.0 μm). ) Insulated wire was obtained.
[0028]
Example 8
The test shown below was done about the insulated wire obtained in Examples 1-7 and Comparative Examples 1-3. The results are shown in Table 1.
{Circle around (1)} Paint Stability Each lubricant coating used in Examples 1 to 7 and Comparative Examples 1 to 3 was allowed to stand at room temperature for 7 days and evaluated by the presence or absence of precipitation.
○: No precipitation occurred ×: Precipitation occurred (2) Coefficient of static friction Measured by the test method of JIS K 7125.
(3) Wear resistance (reciprocating type)
It was measured by the old JIS C 3003 test method.
(4) An impregnated varnish-coated insulated wire was tightly wound around a 6.5 mm mandrel to prepare a helical coil having a length of 75 mm. After preheating at 190 ° C., an epoxy resin powder varnish (Epiform F290 ( The product was soaked in a product name, manufactured by Somar Inc.) and then pulled up and thermally cured at 180 ° C. The appearance of this coil was visually observed and evaluated as follows.
○: The varnish adheres uniformly and the surface is smooth.
(Triangle | delta): There exists a part in which the varnish is repelled, and the place with an unevenness | corrugation on the surface and a smooth place are mixed.
X: The varnish is repelled and the entire surface is uneven.
(5) Adhesive strength of varnish coating film A helical coil was prepared in the same manner as in (3) above, preheated at 190 ° C, immersed in an epoxy resin powder varnish, pulled up, and cured at 180 ° C. I let you. About this coil, the adhesive force of the varnish coating film at normal temperature was measured by the method based on ASTM-D-2519.
[0029]
[Table 1]

[0030]
As is clear from the results in Table 1, the insulated wires obtained in Examples 1 to 7 have good wear resistance and excellent coil workability, and the varnish when the coil is treated with a powder epoxy resin varnish. Was evenly adhered to the surface, and the adhesion of the varnish coating was also high. The coil obtained by the method of the present invention had little film damage due to coil winding, and the electric wires were sufficiently fixed with varnish.
On the other hand, in the insulated wires of Comparative Examples 1 and 2, a phenomenon that the surface repels the varnish in the impregnation varnish treatment of the coil was observed, and the adhesive force of the varnish coating film was low. In the insulated wire of Comparative Example 3, the varnish was partially attached without being repelled, but the adhesive force was lower than that of the Example and was not sufficient. Further, the lubricant paint No. 5 used in Comparative Example 3 had poor stability, and precipitation occurred 7 days after production.
[0031]
【The invention's effect】
The insulated wire of the present invention has a self-lubricating property that can withstand severe coil processing conditions and is excellent in impregnating varnish coatability. Therefore, the insulated wire of the present invention enables the impregnating varnish treatment of the self-lubricating enameled wire which has been insufficient or difficult in the past. Therefore, if the coil processing which performs an impregnation varnish process after coiling using such an insulated wire is performed, a coil having excellent wear resistance and coil workability and excellent adhesion by varnish can be obtained.

Claims (3)

An insulated wire having at least one insulating layer formed by applying and baking an insulating paint on a conductor, and a lubricant layer formed by applying and baking a lubricant to the surface layer of the coating layer having the insulating layer. The antifriction agent contains a wax and a thermosetting resin, and rosin resin or maleic resin is added to 100 parts by weight of the lubricant solid content excluding rosin resin and maleic resin. An insulated wire comprising 3 to 20 parts by weight.   The insulated wire according to claim 1, wherein the insulating coating forming the insulating layer comprises a polyamideimide resin.   A method for producing a coil, wherein the insulated wire according to claim 1 is coiled and subjected to an impregnation varnish treatment.