JPS6013453A - Manufacture of insulated coil for electric machine - Google Patents

Abstract

PURPOSE:To prevent resin impregnated in the interior from flowing out by winding a resin-flowout preventive tape held with curing accelerator of specific resin on the outer periphery of a main insulating layer, and then impregnating and curing the resin. CONSTITUTION:A resin-flowout preventive tape held with resin curing accelerator formed of the additive product of 2-ethyl-4-methylimidazole and the third class carboxylic glycidyl ester represented by the general formula ( I ) is wound on the outer periphery of a main insulating layer. Then, resin is impregnated and cured. The resin impregnated with the layer is rapidly cured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the manufacture of IE electrical insulating wires such as high-voltage motor coils, and in particular, to manufacturing methods that are designed to prevent resin from flowing out by being impregnated into the insulating layer during resin impregnation treatment. The present invention relates to a method and a spill prevention tape used therein.

In the resin impregnation treatment of insulated wire rings for electrical equipment, it is essential that the impregnated resin be retained without flowing out during curing in order to ensure its insulation performance.

However, since Kaiyu resin is generally used repeatedly, it uses a resin formulation with a long shelf life (pot life), so it often takes a long time to harden, and the disadvantage is that the resin flows out during this time. have.

In order to compensate for these drawbacks of impregnated resin and prevent the resin from flowing out, the conventional method! 7 Various methods have been taken, but
One of these is a method in which a leak-prevention tape in which a curing accelerator for impregnated resin is held in various tape materials is wound around the outermost circumference of the insulating layer, and then resin is impregnated and cured.

This method has good economic efficiency and workability.

The reaction accelerator held in the tape greatly influences its leakage prevention performance.

The curing accelerator to be retained in the read prevention tape must have the following properties.

0) High curing accelerating ability for impregnated resin.

(2) Due to the drying process of the coil that is performed before resin condensation (the number of coils should not be increased).

In order to satisfy these conditions tl-, there are examples of using imidazole compounds with high melting points, such as 2PHZ-ON [trade name: manufactured by Shikoku Kasei Kogyo Co., Ltd.], but such high melting point imidazole compounds do not accelerate curing. ability is not sufficient.

In terms of curing accelerating ability, low molecular weight imidazole compounds such as 2M2.2E4MZ (both trade names Nishikoku Kasei Kogyo Co., Ltd. H) are preferable, but these low molecular weight imidazole compounds have high sublimation properties. , does not satisfy the condition (2) above.

As a result of various experimental studies, the present inventors have achieved the above (1) by eliminating the sublimation property without impairing the excellent curing accelerating ability of a low molecular weight imidazole compound.

By finding a curing accelerator that satisfies the condition (2) and using a resin spill prevention tape that retains it, the above-mentioned problem was solved.

That is, 1. The present invention uses 2g+MZ and a tertiary caldenic acid glycidyl ester represented by the following formula (where 几 is a saturated fat chain of 08 to 010) [commercially available from Yuka Shell Epoxy Co., Ltd. under the trade name Cardura E]. MgK (methyl
The above-mentioned problems have been successfully solved by treating various tape materials with a solution dissolved in a solvent such as ethyl chloride, and using a spill-preventing tape that retains the added product.

The tape material used here is selected from glass tapes, polyester spun tapes, polyester films, tapes such as polyimide films, polyester nonwoven fabrics, aromatic polyamide tapes, and the like.

Furthermore, there are no particular restrictions on the epoxy resin, acid anhydride curing agent, and curing accelerator that are blended into the impregnated resin.

Examples of epoxy resins include polyglycidyl ether obtained from polyhydric phenol and polyhydric alcohol and epichlorohydrin, and epoxy resin obtained from )-knock type phenol and epichlorohydrin. -ytsuku, polyolein-based epoxy resins synthesized by peroxidation method, polyglycidyl esters obtained from cyclopentadiene oxide, cyclohexene oxide, hexahydroctate acid, etc. and epichlorohydrin, etc.1 Commonly used grave poxy resins is used singly or in combination of two or more types.

Examples of the acid anhydride curing agent include 7-talic anhydride, hexahydrophthalic anhydride, methyltetrahydro-7-talic anhydride,
Methyl hexahytotetraphthalic anhydride, etc. are used, and tertiary R amines and their salts, carunic acid metal salts, and imidazole compounds are used as curing accelerators, and are added to the impregnated resin or used in the main insulating layer. It is held on the tape sheet that is used.

Specific examples of the present invention will be described below.

Example 1 First, a leakage prevention tape according to the present invention was prepared in the following manner.

2 g of MZ and 5 g of kash equimolar tk are reacted at about 60° C. in a reaction vessel to obtain a viscous addition product;
Dissolve this in a solvent of methyl ethyl lactone to make a 2% solution, and add a total of 0.13 x 19 glass tape to this solution.
The sample after soaking for 0 minutes is taken out and air-dried to obtain a leakage prevention tape according to the present invention (hereinafter referred to as the tape of the present invention).

The flow of the above invention! In order to compare with the fI prevention tape, a spill prevention tape impregnated with only %2Ii:4MZ and cured (hereinafter referred to as the first comparison tape, 2PHZ-ON
A leak-preventing tape F (hereinafter referred to as the second comparison tape) which was impregnated with hardened tape was prepared.

Next, the above-mentioned tape of the present invention and the first and second comparison tapes were each cut into a length of 2 m, and the tape was cut into a length of 2 m at 150°C.
2 m of heated and untreated glass stage
I) ER332 (bisphenol A epoxy resin: manufactured by Dow Chemical Company) 1
After being immersed for 5 minutes in an impregnated resin consisting of 0.00 parts, 80 parts of HN220υ [methyltetrahydro-7-taric anhydride: manufactured by Hitachi Chemical Co., Ltd.], and 0.2 parts of 61BC modified amine: manufactured by Sale Chimney Co., Ltd., and pulled up. Immediately they were placed in a constant temperature bath set at 150°C and cured for 10 hours, and the amount of resin deposited was compared.

As shown in Table 1, the results are as follows for the first comparative tape:
The tape without heat treatment showed adhesion IT equivalent to that of the present invention tape, but when heat treated, 2g4Mz volatilized and the adhesion-height was extremely reduced.

In the case of the second comparison tape, the decrease in the amount of adhesion due to heat treatment was small, but the increase was small compared to the amount of adhesion of the untreated tape, indicating that the curing accelerating ability of 2Pf (Z-ON) was low. There is.

In contrast to these comparative examples, the tape of the present invention has a large amount of resin +j deposited, is not affected by heat treatment, and is clearly an excellent outflow prevention cheese.

Table 1 (Measurement of adhesion of impregnated resin) Example 2 The coil is wound three times with a knob to form the main insulation layer.

After drying the coil at 150°C for 10 hours, the insulated coil was impregnated with the impregnating resin used in Example 1 under full vacuum and pressure, and cured at 150°C for 10 hours.

We compared the applied voltage-tana characteristics7 and the results are shown in Figure 5. Even when the applied voltage is high, the coil using the tape of the present invention has a tana of 1% or less (shown by the solid line). ), tana exceeds 1% in the high pressure region (clearly superior to the coil shown by the dotted line and using the second comparative tape).

As described above, according to the method for manufacturing an electric machine wire wheel in which the tape of the present invention is wound around the outermost circumference of the electric wire wheel, completely impregnated with resin, and cured, the resin impregnated into the spill prevention tape layer is quickly cured. This prevents the resin impregnated inside the shell from flowing out and deteriorating the electrical, mechanical, and thermal characteristics, thereby ensuring full insulation performance.

[Brief explanation of drawings]

The drawing is an applied voltage-electrical protection tangent characteristic diagram of the example.

Claims (2)

[Claims] (1) A main insulating layer is formed around the conductor, and a polyfunctional epoxy resin and a polyfunctional acid anhydride are added to the main insulating layer. In a method for manufacturing electrical insulating wires impregnated with a resin containing a curing agent as a main component, addition of 2-ethyl-4-methylimidazole and hemp tertiary carboxylic acid glycidyl ester represented by the following formula (%) A method for producing a Ni electric insulating wire, comprising: winding a resin spill prevention tape holding a curing accelerator for the resin made of a product around the outer periphery of the main insulating layer, and then impregnating and curing the resin. (2) A curing accelerator consisting of an addition product of 2-ethyl-4-methylimidazole and tertiary carzene acid glycidyl ester represented by the following formula % (where 几 is a saturated fatty chain of 08 to 01G). m JJ'fH leakage prevention tape characterized by being held by the tape.