JPH0356558A - Resin composition for electrical insulating treatment, electrical insulating treatment and stator coil - Google Patents

Abstract

PURPOSE:To obtain a resin composition for electrical insulating treatment, capable of providing an electrically insulated stator coil, having excellent flame retardance by simplified electrical insulating treatment process, comprising an unsaturated polyester resin, aluminum hydroxide and silica powder. CONSTITUTION:A resin composition for electrical insulating treatment comprising (A) 100 pts. wt. unsaturated polyester resin curable by heat or light and heat, (B) 100-200 pst. wt. aluminum hydroxide having >=99 % content shown by formula I or formula II, 2-3 true specific gravity, <=5mum particle size distribution and <=0.5 adsorption water content and (C) 0.1-3 pts. wt. silica powder, preferably silica fine powder. End part of stator coil having coil end part not bundled with yarn is impregnated with the composition, the coil is inverted, the other end is similarly impregnated and the composition is cured by heat, etc., while inverting the coil to give an electrically insulated stator coil.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a resin composition for insulation treatment, a method for insulation treatment of an insulated stator coil used in home appliances, etc., and an insulation treated stator coil. ．． [Conventional technology] Conventionally, methods for insulation treatment of stator coils include (1)
Bind the coil end with thread and tie it to 0. Stator coated with liquid varnish of about 1 to 3 poise. How to impregnate the entire coil, (
2) Method of dripping and impregnating only the coil part with varnish, (3
) A method in which powder varnish is used to heat and harden only the coil portion, and (4) a method in which the entire stator coil is molded using a compound. The method using liquid varnish has low material costs and the varnish treatment process is easy to automate; however, the varnish tends to flow out during curing, the amount of varnish adhered to the coil end after curing is small, and it is susceptible to vibration and impact. The disadvantage is that the insulation properties are lower and the insulation properties are poor under high humidity. Another problem was that the varnish used itself lacked flame retardancy.

The method using powder varnish can omit the bundling process of the coil ends and automate the insulation treatment process, but since the powder varnish does not contain the inside of the coil, it is difficult to insulate under high humidity. There are disadvantages that are inferior to gender. Further, there were other problems such as the powder varnish used itself lacked flame retardancy, produced a large amount of smoke when burned, and generated a large amount of harmful substances.

The method of molding the entire stator coil using a compound is effective in making the motor quieter and improving moisture resistance, but it is difficult to automate the insulation process and the material cost is relatively high. In addition, there were other problems such as the inferior flame retardancy of Conbound itself.

Particularly in recent years, there has been a strong demand for motors to be safer (improved flame retardancy), quieter (improved adhesion), and lower in price (rationalized insulation treatment process, shorter processing time). It is rare. [Problems to be Solved by the Invention] An object of the present invention is to solve the problems of the prior art described above, to make the motor flame retardant, quiet, and highly reliable against moisture deterioration, and to improve the coil of the stator coil. It is an object of the present invention to provide a resin assembly for insulation treatment, a method for insulation treatment of a stator coil, and an insulation treatment treated stator coil, which can shorten the insulation treatment process by omitting binding with threads at the end portions.

[Means to solve the problem]

The present invention consists of 100 parts by weight of an unsaturated polyester resin that is cured by heat or light and heat, and 100 parts by weight of aluminum hydroxide.
200 parts by weight and silica powder O. A resin composition for insulation treatment containing 1 to 3 parts by weight, one coil end portion of a stator coil whose coil end portions are not bound with thread is impregnated with this resin composition for insulation treatment, and then the stator coil A method for insulation treatment of a stator coil, in which the other coil end is impregnated with the resin composition for insulation treatment, and then the stator coil with both coil end portions impregnated is cured by heat or light and heat while being reversed. and stator coils treated with this insulation treatment method. The unsaturated polyester resin used in the present invention includes:
There is no particular restriction as long as it can be cured by heat or light and heat, and can be obtained by, for example, unsaturated polyester, epoxy ester having a reactive unsaturated bond, etc., containing a crosslinkable monomer and a peroxide. Additionally, photosensitizers, accelerators, polymerization inhibitors, etc. can be used as necessary. The unsaturated polyester is synthesized from an acid component and an alcohol component, or an acid component, an alcohol component, and a modifying component. As acid compounds, maleic acid, maleic anhydride,
Unsaturated acids such as fumaric acid, itaconic acid, citraconic acid, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid,
Saturated acids such as tetrahydrophthalic anhydride and adipic acid, vegetable oil fatty acids such as soybean oil, tall oil, coconut oil, and castor oil are used. Examples of the alcohol used include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, butanediol, neobentyl glycol, glycerin, trimethylolpropane, and pentaerythritol. Further, as the modified component, dicyclopentadiene, cyclopentadiene and derivatives thereof are used.

An epoxy ester having a reactive unsaturated bond is synthesized from an epoxy resin having one or more epoxy groups in one molecule and an acid having an unsaturated bond. As the epoxy resin, bisphenol A type epoxy resins are preferred, such as Epicote 828, 1001, and 1004 (manufactured by Shell Chemical Co., Ltd.). Acrylic acid, methacrylic acid, maleic anhydride, etc. can be used as the acid having an unsaturated bond.

Examples of the crosslinkable monomer include styrene, vinyltoluene, α-methylstyrene, tertiarybutylstyrene,
Divinylbenzene, various acrylic esters, various methacrylic esters, diallyl phthalate, etc. are used.

Peroxides include acyl peroxides such as penzoyl peroxide and acetyl peroxide, hydroperoxides such as tertiary butyl hydroperoxide and cumene hydroperoxide, ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide, Dialkyl peroxides such as ditertiary butyl peroxide and dicumyl peroxide are used. The amount added is 0.0% based on the total amount of unsaturated polyester and crosslinkable monomer. It is preferably in the range of 5-3%.

Examples of photosensitizers used as necessary include benzoin ethers such as benzoin ethyl ether and penzoin isopropyl ether, acetophenones such as acetophenone and 2,2-dimethoxy-2-phenylacetophenone, and penzoin-Hiller's ketone. , penzointhioethers, anthraquinones, etc. are used.

The amount added is 0.0% based on the total amount of unsaturated polyester and crosslinkable monomer. It is preferably in the range of 1 to 3% by weight.

Further, as the accelerator, metal soaps and amines such as manganese naphthenate, zinc naphthenate, cobalt naphthenate, and cobalt octenoate are used.

As the polymerization inhibitor, hydroquinone, tertiarybutylhydroquinone, p-penzoquinone, 2,5-ditertiarybutylhydroquinone, etc. are used.

Aluminum hydroxide used in the present invention is not particularly limited, but Af (OH). Or Al! Os・3H,O
The content is 99% or more, and the true specific gravity is 2.0 to 3. 0, has a particle size distribution of 5 μm or less, and has an adsorbed moisture content of 0.
．． The content is preferably 5% or less. As the aluminum hydroxide, commercially available products such as Higilite (trade name) manufactured by Showa Denko Co., Ltd., and granular alumina commercially available from Sumitomo Chemical Co., Ltd., Nippon Light Metal Co., Ltd., etc. are preferably used. The amount of aluminum hydroxide used is 100 to 200 parts by weight per 100 parts by weight of the unsaturated polyester resin. If this amount is less than 100 parts by weight, the flame retardance cannot be improved, and the varnish on the coil The amount of adhesion decreases.

Moreover, if it exceeds 200 parts by weight, the viscosity becomes high and the ability to contain it inside the coil decreases. There are no particular restrictions on the silica powder used in the present invention, but
Finely powdered silica such as Erogil (manufactured by Nippon Aerosil Co., Ltd.) is preferred. This usage amount is 1 part of unsaturated polyester resin.
The amount is 0.1 to 3 parts by weight per 00 parts by weight. If the amount used is less than 0.1 parts by weight, precipitation of aluminum hydroxide will be large, making it impossible to obtain a uniform composition, and if it exceeds 3 parts by weight, the viscosity will be high, the thixotropy will be large, and the content inside the coil will be increased. Manifestability decreases.

The insulation treatment resin &Il of the present invention is obtained by mixing the unsaturated polyester resin, aluminum hydroxide, and silica powder using a high-speed stirrer or the like.

In the present invention, the insulation treatment of the stator coil is performed, for example, as follows using the resin composition for insulation treatment.

First, it is preferable to heat the stator coil, whose coil end portions are not bound with thread, in advance at high speed using an electrical heating method or a high frequency induction heating method. Next, one coil end of this stator coil is immersed in an insulation treatment resin composition up to the slot surface, and then the stator coil is lifted out of the insulation treatment composition and turned over, and the other coil end is similarly insulated. It is immersed in a treatment resin composition and then pulled up. Next, this stator coil is cured by heat or light and heat while being turned over in a curing furnace so that both coil end portions are alternately placed vertically.

Inversion in the curing oven takes place at time intervals.

Ultraviolet rays are used for photocuring, and ultraviolet rays, high frequency waves, etc. are used for thermosetting.

As described above, by inverting the coil end portion as described above and immersing it in varnish in a liquid unsaturated polyester resin composition highly filled with aluminum hydroxide, and then inverting and curing as described above. In addition, it is possible to omit the need for binding the coil end portions with threads, increase the amount of varnish deposited, and manufacture a stator coil that has good impurity inside the coil.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, in the examples, parts mean parts by weight.

Example 1 1) Production of resin composition for insulation treatment Propylene glycol 532L Ethylene glycol 24
8 parts, 441 parts of maleic anhydride, 150 parts of phthalic anhydride, and 0.8 parts of hydroquinone. 4 parts were placed in a 4-necked flask and heated to 180°C for 1.5 hours under nitrogen gas blowing. The mixture was kept for 5 hours, and then the reaction was continued at 220°C to obtain unsaturated polyester A with an acid value of 18.0. This unsaturated polyester A5
5 parts, 45 parts of styrene monomer, 0.5 parts of manganese naphthenate.
2 parts, 1.5 parts of penzoyl peroxide, Hygilite H-32 (manufactured by Showa Denko, aluminum hydroxide) 11
0 part and Erogil 380 (manufactured by Nippon Aerosil Co., Ltd.,
1 part of fine powder (non-silica) was mixed using a high-speed stirrer to obtain a resin composition (A).

2) Insulating the stator coil Stator coil without binding the coil end with thread (Rating: 100 V, output: 100 W, 17 dimensions: 10 mm)
X110mmX40ma+, diameter 0. 6 m
The coil temperature was raised to 100°C to perform preheating. This coil was air-cooled, and when the surface temperature of the coil reached 80° C., one end of the coil was immersed in the resin composition (A) up to the slot surface and held for about 30 seconds. Next, this stator coil was pulled up, immediately reversed, and the other end of the coil was dipped and impregnated with the resin composition (A) up to the slot surface, and maintained for about 30 seconds. Next, the stator coil was pulled up, immediately turned over, and heated and cured in a far-infrared curing oven (135°C). After 2 minutes and then 3 minutes after the start of curing, the stator coil was reversed to make the amount of resin adhered uniform, and then, while maintaining this state, it was heated and cured at 135°C for 25 minutes, and the stator coil was insulated. .

Example 2 1) Production of resin composition for insulation treatment 55 parts of unsaturated polyester A obtained in Example 1, 45 parts of styrene monomer, 0.2 part of manganese naphthenate, 1.0 parts of penzoyl peroxide. 0 parts, benzoin ethyl ether 1.0 parts, Hygilite H-32 (manufactured by Showa Denko, aluminum ξnium hydroxide) 110 parts and Erosil 38
0 (manufactured by Nippon Aerosil Co., Ltd., fine powder silica) was mixed using a high-speed stirrer to obtain a resin composition (B).

2) Stator Coil Insulation Treatment A stator coil of the same type as the stator coil used in Example 1 was energized and the coil temperature was raised to 100°C to perform preheating. This coil was air-cooled, and when the surface temperature of the coil reached 80°C, one end of the coil was immersed in the resin composition (B) up to the slot surface, and the coil was soaked for about 30°C.
held for seconds. Next, this stator coil was pulled up and immediately reversed, and the other end of the coil was immersed and impregnated in the resin assembly (B) up to the slot surface, and held for about 30 seconds. Thereafter, the stator coil was pulled up, immediately reversed, and ultraviolet rays were irradiated for 2 minutes from a distance of 25 cm using a high-pressure mercury lamp manufactured by Oak. Next, this stator coil was turned over and similarly irradiated with ultraviolet rays for 2 minutes to harden the surface.
The stator coil was insulated by heating in a high frequency induction heating furnace at 5°C for 15 minutes.

Comparative Example 1 55 parts of the unsaturated polyester A obtained in Example 1, 45 parts of styrene monomer, 0.5 parts of manganese naphthenate. 2 parts and penzoyl peroxide 1. Mix and stir 5 parts,
A resin composite sole (C) was obtained.

Next, a stator coil of the same type as that used in Example 1 was energized, and the coil temperature was raised to 100°C to preheat it. This coil is air-cooled, and when the coil surface temperature reaches 50°C, the entire coil is coated with a resin composition (C
), the entire stator coil was dipped and impregnated and held for 30 seconds. Thereafter, this coil was pulled up, and dropwise addition was continued for approximately 10 minutes at room temperature, followed by heat curing for 30 minutes in a far-infrared curing oven at 135°C.

Comparative Example 2 ■) Manufacture of powder coating Epicor} 1007 (manufactured by Shell Chemical) 100 parts, 2,
4-diamino-6-[2-methylimidazole (1)
] 2 parts of monoethyl triazine (2MZ-AZINE, manufactured by Shikoku Kakogyo Co., Ltd.), 0.5 parts of Erogil 200 (manufactured by Nippon Aerosil Co., Ltd., finely powdered non-silica), 50 parts of Calcium Carbonate Silver W (manufactured by Shiraishi Kogyo Co., Ltd.), and Modaclo (Surfactant manufactured by Monsanto Co., Ltd., acrylic copolymer) 1 part were dry mixed and then melt-kneaded at 90°C. After cooling, it was pulverized in a mill and passed through a 180-am sieve, which was used as a powder coating (D). 2) Stator coil insulation treatment A stator coil of the same type as the stator coil used in Example 1 was electrically heated to 160°C, and one end of the coil was coated with powder paint (D). It was cured by holding at 160°C for 5 minutes.Then, the other coil end was coated with powder paint, and it was cured by holding at 160℃ for 5 minutes, and the stator coil was insulated. For the stator coils obtained in Comparative Examples 1 and 2 and Comparative Examples 1 and 2, the hardenability and flame retardance of the stator coil surface and the moisture resistance life of the motor were measured, and the results are shown in Table 1.

Table 1 *l: The core was evaluated by finger touch, and a state of no adhesion was rated as ○.

*2: The protector attached to the stator coil was removed, and IOOV was applied to continue energization preheating, causing a layer short circuit.

*3: 600cm in 60°C-95%RH (relative humidity)
was applied, and the time until dielectric breakdown occurred was measured.

From the above results, it was shown that the stator coil of this example has superior flame retardancy and moisture resistance life compared to stator coils obtained by conventional methods.

〔Effect of the invention〕

The resin composition for insulation treatment of the present invention has excellent flame retardancy, and as a result, it is possible to improve the time required to reach ignition and the flame ignition time in a combustion test of an insulated stenitor coil. Furthermore, according to the manufacturing method of the present invention, it is possible to omit binding the coil ends of the stator coils with threads, and since a liquid resin composite is used, automation of the processing process is easy. Furthermore, the stator coil obtained by the manufacturing method of the present invention has a large amount of varnish deposited, has excellent impregnation into the inside of the coil, and has excellent moisture resistance and life characteristics.

Claims (3)

[Claims] 1. 100 parts by weight of unsaturated polyester resin that cures with heat or light and heat, 100-200 parts of aluminum hydroxide
A resin composition for insulation treatment, comprising parts by weight and 0.1 to 3 parts by weight of silica powder. 2. After impregnating one coil end portion of a stator coil whose coil end portions are not bound with thread with the resin composition for insulation treatment according to claim 1, the stator coil is reversed and the other coil end portion is subjected to the insulation treatment as described above. 1. A method for insulating a stator coil, the method comprising: impregnating the stator coil with a resin composition, and then curing the stator coil with heat or light and heat while inverting the stator coil with both coil end portions impregnated. 3. A stator coil treated by the insulation treatment method according to claim 2.