JPS5861605A - Insulated coil - Google Patents

Abstract

PURPOSE:To obtain the insulator for an insulated coil having the superior electric characteristics and mechanical characteristics by a method wherein slurry is made using non-baked mica ramenta of plural kind of which grain size and the ratio of aspect is made to differ respectively, and the composite mica material thereof obtained by making in paper and a thermosetting resin mterial are mixed prescribing the weight part respectively. CONSTITUTION:Non-baked mica is pulverized to make mica ramenta of 2-25 weight part having grain size of 1.7mm. or more, and moreover having the ratio of aspect of 150 or more. Similarly, mica ramenta of 20-60 weight part having grain size less than 1.0-1.7mm. and having the ratio of aspect of 150 or more, and mica ramenta of 20-40 weight part having grain size less than 0.25-1.0mm. and having the ratio of aspect of 100 or more, are made. Moreover mica ramenta of 10-30 weight part having grain size less than 0.25mm. and having the ratio of aspect of 100 or more is made, and the composite mica material of 60-85 weight part consisting of slurry obtained by mixing them and the thermosetting resin composite of 15-30 weight part are applied to a glass cloth lining material of 15 weight part or less to produce the coil insulating material.

Description

[Detailed description of the invention] The present invention relates to an insulated coil.

Conventionally, insulated wire rings are made by wrapping a peelable mica tape around a conductor, and then wrapping it with an epoxy resin composition.

It is manufactured by the so-called prepreg method, in which a thermosetting resin composition such as an unsaturated polyester resin composition is vacuum impregnated and cured for 90 minutes, or a so-called prepreg method in which baked mica prepreg tape is wound around a conductor and then heated and pressure molded. ing. The prepreg method was superior to the initial electrical properties, and the vacuum impregnation method using removable mica tape was superior to the electrical properties after long-term deterioration of the source material.

There is no insulated wire ring made of laminated mica that has properties equal to or better than those made of fi-removable mica; No. 20264. This method has disadvantages, such as the need for a complicated manufacturing process such as infiltrating the raw material mica with an aqueous solution of hydrofluoric acid or hydrogen chloride, and the need for wastewater treatment.Also, since it uses calcined mica, the resulting insulated wire Mechanical properties were also not sufficient.

The present invention solves these drawbacks and provides an insulated wire ring with excellent electrical and mechanical properties.

The present invention is based on particle size 1.7 obtained by pulverizing uncalcined mica.
2 to 25 parts by weight of mica flakes with a tl of 1 or more and an aspect ratio of 15 degrees or more 1 20 to 60 parts of mica flakes with a particle size of 1.0 to 1.7 cm and an aspect ratio of 150 or more Weight part.

20 to 40 parts by weight of mica flakes with a particle size of 0.25 m or more and less than 1.0 and an aspect ratio of 100 or more; and mica flakes with a particle size of less than 0.25 m and an aspect ratio of 100 or more. 60 to 85 parts by weight of a laminated mica material obtained by paper-making a slurry containing 10 to 30 parts by weight, 15 to 30 parts by weight of a thermosetting resin composition, and 15 parts by weight of a backing material.
The present invention relates to an insulated coil having an insulating layer containing not more than part by weight.

KFi when calcined mica is used instead of uncalcined mica
, the mechanical properties of the insulated coil, especially the bending strength and bending modulus, are significantly reduced.

What is the aspect ratio in the present invention?

The particle size distribution was calculated by wet classification using a standard analytical sieve and then measuring the weight after drying. A method for pulverizing uncalcined mica to the particle size distribution and aspect ratio of the present invention is described in Japanese Patent Publication No. 54-8899, %N 1982-39.
Natsu9 was made possible for the first time by the method shown in Publication No. 984. By these methods, mica flakes having a large aspect ratio and a desired particle size distribution can be easily obtained.

If the mica scale pieces having a particle size of 1.7 mm or more and an aspect ratio of 150 or more are less than 2 parts by weight, the reinforcing effect of the mica scale pieces is small, resulting in a decrease in mechanical and electrical properties. Moreover, if it exceeds 25 parts by weight, the number of voids between the mica pieces increases, so that a large amount of the thermosetting resin composition is required to fill the voids, and the mechanical and electrical properties deteriorate. Particle size 1.0- or more1.
If the amount of mica flakes less than 7 parts and having an aspect ratio of 150 or more is less than 20 parts by weight, the reinforcing effect of the mica flakes is small, resulting in poor mechanical and electrical properties. If the amount exceeds 60 parts by weight, the mica flakes will have more voids, which will require more thermosetting resin composition to fill the voids, resulting in lower mechanical and electrical properties. Particle size 0.25■ or more 1゜0sII
If the amount of mica flakes with an aspect ratio of 100 or more is less than 20 parts by weight, the mica flakes will not be able to effectively fill the voids in the mica flakes, resulting in poor mechanical and electrical properties. descend.

Moreover, if it is contained in an amount exceeding 40 parts by weight, the proportion of small mica flakes increases and the mechanical properties are deteriorated.

Less than 10 parts by weight of mica flakes having a particle size of less than 0.25 m and an aspect ratio of 100 or more.

If it is not included, the voids in the large mica flakes cannot be effectively filled and the mechanical and electrical properties deteriorate.

(9) If it is contained in an amount of 30 parts by weight or more, the proportion of small mica flakes increases, resulting in a decrease in mechanical and electrical properties. Mica flakes with a grain size of 1.7 or more and mica flakes with a particle size of 1,0111 or more and less than 1.7111 with an aspect ratio of less than 150 or a grain size of 0.25 or more and 1
．． If the aspect ratio of mica flakes less than 0- or less than 0.25 cm has an aspect ratio of less than 100゛,
The mechanical and electrical properties of the resulting insulated coil are degraded.

A slurry containing squid pieces is made into a slurry nine times later, and this is made into paper using a fourdrinier paper machine, a circular wire paper machine, or the like.

The method for forming the insulating layer may be either the vacuum impregnation method or the BRIGREG method, and there are no restrictions on the conditions under which it is formed. A laminated mica material with a necessary backing material is wound around a conductor, placed in a reduced pressure atmosphere, impregnated with a thermosetting resin composition or impregnated with pressure, and then cured with the thermosetting resin composition to form an insulated wire. This mica laminated material is impregnated with a thermosetting resin composition and semi-cured to form a laminated mica grip preg material, which is then wound around a conductor and the impregnated thermosetting resin composition is cured. It is used as an insulated wire ring.

As the thermosetting resin composition in the present invention.

Epoxy resin compositions, unsaturated polyester resin compositions, etc. containing a curing agent, a surfactant, a reactive solvent, etc. can be used without any particular limitation.

The backing material in the present invention is not limited to 1%, and for example, organic or inorganic woven fabrics, nonwoven fabrics, films, etc. such as polyester, polyamide, glass, etc. can be used alone or in combination if necessary.

Furthermore, these may be used in combination with glass yarn, polyester fiber yarn, etc.

The aggregate mica material is used in an amount of 60 to 85 parts by weight, the thermosetting resin composition is used in an amount of 15 to 30 parts by weight, and the No. 14 batting material is used in an amount of 15 parts by weight or less, so that the total amount thereof is 100 parts by weight.

The laminated mica material is used in a range of 60 to 85 parts by weight, but if it is less than 60 parts by weight, the electrical properties such as withstand voltage of the insulated wire will deteriorate, and if it exceeds 85 parts by weight, the voids between the mica pieces will deteriorate. If there are many cases, the electrical properties and mechanical properties of the insulated wire ring will be significantly reduced.

When the amount of the thermosetting resin composition in the insulating layer is less than 15 parts by weight, voids are likely to be formed in the insulating layer.

These voids cause corona discharge and deteriorate the electrical properties of the insulated wire, and when stress such as bending or compression is applied, stress concentration occurs and the mechanical properties also deteriorate.

Furthermore, if the amount of the thermosetting resin composition in the insulating layer exceeds 30 parts by weight, not only the mechanical properties will deteriorate, but also the electrical properties after long-term deterioration.

Backing material is a must! Although it is not necessary to use it, if it exceeds 15 parts by weight in the insulating layer, it deteriorates the mechanical or electrical properties of the insulated wire.

For example, if more than 15 parts by weight of glass fiber woven or nonwoven fabric is used as a backing material, the mechanical properties will not deteriorate, but the electrical properties will deteriorate.

In addition, films and woven fabrics such as polyester and polyamide,
If more than 15 parts by weight of nonwoven fabric is used as a backing material, the mechanical properties will deteriorate, and the electrical properties will also deteriorate after long-term deterioration.

Similar results are obtained when the above-mentioned film is combined with fiber yarns such as glass and polyester.

The present invention will be explained below with reference to Examples.

Example 1 The epoxy resin composition shown in Table 2 was heated to 60°C on the sheet (laminated mica material) 1 shown in Table 1 to form a sheet of 100117 m''.
This was coated with glass cloth (35 t/m") as a backing material and semi-cured by heating at 80°C for 1 hour to obtain a laminated mica pre-preg material. This was cut into tapes with a width of 3011111.

Width 9.5 wx x Height 3a51EII x Length 1000
．． After wrapping it around a 1111 conductor (made of copper) 8 times while overlapping half of it, it was heated to 100°C and pressed, and the above-mentioned epoxy resin composition in the Mikaburi Greg material was heated to 170°C and cured while flowing ( (3 hours) Nine coils with an insulating layer approximately 3 m thick were manufactured. Four coils were manufactured, two were tested under normal conditions, and two were tested after a thermal deterioration test (130°C for IO hours).The test was conducted by measuring the dielectric breakdown voltage at a boost rate of 2KV/sec, and then by four-point bending. Test (outer span 550
wx, inner span 250-1 test speed 5w17 minutes).9. The amount of adhesive (epoxy resin composition) is 6
It was determined by heating at 00°C for 2 hours.

The results are shown in Table 3 as average values.

Example 2 The epoxy resin composition shown in Table 3 was heated to 60°C and coated on Sheet 2 listed in Table 1 to 10,077 m", and glass cloth (3,517 m") was laminated as a backing material.
The mixture was semi-cured by heating at 0° C. for 1 hour to obtain a composite mica brig material. After cutting this into a 30-width tape, it was used in Example 1 and wound around the nine conductors 8 times with half overlap, and then four coils were manufactured under the same conditions as Dormitory Example 1. The test was conducted under the same conditions as in Example 1, and the results are shown in Table 3 as average values.

Example 3 The epoxy resin composition shown in Table 2 was heated to 60°C and applied to Sheet 3 shown in Table 1 for 10,077 m''.

Glass cloth (35 fir/f@") was laminated as a backing material and semi-cured by heating at 80°C for 1 hour to obtain a laminated mica frig material. After cutting this into a tape of 305 m + width, Example 1 was prepared. After wrapping the conductor used in 8 times with half overlap, four coils were manufactured under the same conditions as in Example 1. Tests were conducted under the same conditions as in Example 1, and the results are shown in Table 3 as average values. Ta.

Comparative Example 1 Sheet 4 shown in Table 1 was heated to 60°C with the epoxy resin composition shown in Table 2 to form a sheet of 10077 m'').

Glass cloth (3597 m") was laminated as a backing material and semi-cured by heating at 80°C for 1 hour to obtain a laminated mica prepreg material. After cutting this into a 30-width tape, it was used in Example 1. After wrapping the coil 8 times around a good conductor with half overlap, the coil was wrapped 4 times under the same conditions as in Example 1.
I made this book. Tests were conducted under the same conditions as in Example 1, and the results are shown in Table 4 as average values.

Comparative Example 2 The epoxy resin composition shown in Table 2 was heated to 60° C. and coated for 10,077 m'' on Sheet 5 shown in Table 1.

A glass cloth <351/m") was laminated as a backing material and semi-cured by heating at 80°C for 1 hour to obtain a mica frig material. This was cut into a 30-width tape, and after 9 days, the material was prepared in Example 1. Use half of it on a good conductor, overlap it with 8
After nine turns, four coils were manufactured under the same conditions as in Example 1. Tested under the same conditions as Example 1 and the results are shown in Table 4 as an average value.
It was shown to.

Example 4 Glass cloth (35) was layered on sheet 2 listed in Table 1 as a reinforcing material, and on top of this, Evo volatile content equivalent 1 listed in Table 2 was added.
After drying at 100°C for 30 minutes and cutting into 30m wide tapes, they were wrapped 8 times around the conductor used in Example 1 with half overlap, and then heated at 100°C. "t" 0.1 mmHg 2 hours M Dry and subsequently heated to 80°C under that pressure.
9. Impregnated with the epoxy resin composition described above. With the coil immersed in the epoxy resin composition, the pressure was returned to normal pressure, and after 1 hour, the coil was taken out and wrapped in i-mil Mylar film (made by Toshi) to prevent the epoxy resin composition from running off. The insulating layer was cured at 110"C for 4 hours and then at 170"C for 3 hours to form an insulating layer with a thickness of 3cm.The test was conducted under the same conditions as in Example 1, and the results are shown in Table 3 as average values.

Comparative Example 3 Sheet 5 listed in Table 1 was used to make a tape under the same conditions as Example 4, and this was used to make a coil under the same conditions as Example 4.

The test was conducted under the same conditions as in Example 1, and the results are shown in Table 3 as average values.

In Table 3, the amount of epoxy resin composition was determined when the insulating layer was heated to 600°C.
It was determined from the amount of weight loss after heating for 2 hours. The bending strength was measured using a 4-point method using an outer span of 550 cm, an inner span of 250 cm, and a test speed of 5 m for 7 minutes.

The dielectric breakdown voltage was determined at a voltage increase rate of 2 KV/sec. The dielectric breakdown voltage after deterioration was determined by determining the dielectric breakdown voltage that did not undergo thermal deterioration at 130° C. for 10 hours in a hot air circulation type electric heat dryer.

The insulated wire ring according to the present invention has large mica flakes and uses a composite mica material with a high aspect ratio, so the mechanical properties of the insulating layer are improved, and the gaps between the large mica flakes are filled with small mica flakes. The electrical properties of the insulating layer are also enhanced.

In addition, by using a composite mica material in which the gaps between large mica flakes are filled with small mica flakes, the initial properties (electrical properties and mechanical properties) of the insulated wire ring can be improved even if the amount of adhesive in the insulating layer is reduced. Not only does it not deteriorate, but the characteristics after long-term deterioration (e.g.

It also has excellent long-term electrical deterioration characteristics, comparable to, or even superior to, insulated wire rings using peelable mica products.

Claims (1)

[Claims] 1. Mica pieces obtained by crushing unfired mica and having a particle size of 1.7 or more and an aspect ratio of 150 or more are
~25 parts by weight9 20 to 60 pieces of mica with a particle size of 1.0 to less than 1.7 and an aspect ratio of 150 or more
Part by weight: 20 to 4 pieces of mica with a grain size of 0.251111 or more and less than 1.0cm and an aspect ratio of 100 or more.
A laminated mica material obtained by paper-making a slurry containing 10 to 30 parts by weight of mica flakes having a particle size of less than 0.25 w and an aspect ratio of 100 or more.
parts by weight, 15 to 30 parts by weight of the thermosetting resin composition and 15 parts by weight or less of the backing material (the aggregate mica material, the thermosetting resin composition, and the backing material have a total amount of 100 parts by weight within the above range).
an insulated coil having an insulating layer containing (in amounts expressed as parts by weight).