JPS59139839A - Manufacture of resin-impregnated and molded coil - Google Patents

Abstract

PURPOSE:To manufacture a product which is electrically and mechanically excellent inexpensively by impregnating resin or varnish curable by ultraviolet ray to a molded strand coil and then emitting the ultraviolet ray and a microwave to cure the impregnated resin. CONSTITUTION:A cylindrical high voltage strand coil 1 is formed of an insulating base material such as polyester non-woven fabric, aramid paper or glass fiber and an insulated conductor such as a refractory enameled wire, a polyester non- woven cloth winding, aramid winding or a glass winding, and a wound core 7 is formed of iron, aluminum or plastic. A leakage preventing layer 12 is formed of polyester non-woven fabric or thermosetting resin felt at the end face of the coil 1. Then, epoxy resin 4 which contains 30wt% of component cured by ultraviolet ray added with photosensitizer to monomer is impregnated to the coil 1, ultraviolet ray 9 is emitted while rotating the coil 1 by a rotating unit 2 to cure the surface, the coil is further introduced into a microwave oven 13, and thermally cured by the microwave 14. In this manner, the coil can be inexpensively manufactured in good productivity in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a resin-impregnated molded filler easily and in a short time using a varnish and a resin composition.

The conventional manufacturing method for O (oil-impregnated molded fill) for electrical equipment is as follows:
The method was to put a base film into a mold, cast resin and harden it, or impregnate it with varnish, then heat and harden it to mold it. However, in recent years, in order to shorten manufacturing time, a coil impregnated with varnish or resin is rotated and irradiated with ultraviolet rays to form a leak-proof film layer on the surface of the coil.
A method has been implemented in which the impregnated resin inside the coil is completely cured by heat treatment.

Next, a conventional method of manufacturing a resin-impregnated molded coil by ultraviolet irradiation will be described with reference to FIGS. 1 to 3. Figure 1 shows a method for manufacturing a molded transformer coil. A coil 1 impregnated with ultraviolet curing resin is set in a rotating device 2, and while rotating at a constant speed in the direction 8 of the arrow in the center of the figure, a high-pressure mercury lamp 3 is used to heat the coil 1 using ultraviolet rays. 9 is irradiated onto the outer peripheral surface of the filler 1 and the coil end surface 5 to form an ultraviolet cured film on the surface of the coil 1. Thereafter, the coil is heated in an oven for 4 to 5 hours while rotating to completely harden the 01 fat inside the coil. Furthermore, after that, the rotation is stopped and the coil is heated in a stationary state. FIG. 2 shows a method of manufacturing a stator fill for an electric motor. While rotating in the direction of the arrow 8 in the figure, turn on the high-pressure mercury lamp 3.
As a result, the varnish is cured by exposing it to ultraviolet light 9.

The parts that are not exposed to 5J ultraviolet rays and the inside of the coil are heated and cured in an oven.

FIG. 3 also shows a method of manufacturing a stator coil for an electric motor, in which a coil 10 impregnated with an ultraviolet curable resin composition is placed in a rotating device 1.
1, and while rotating in the direction 8 of the arrow in the figure, ultraviolet rays 9 are irradiated to cure the -1- resin composition. Areas that are not exposed to UV rays and the inside of the coil are heated and cured in an oven.

A resin-impregnated coil with good properties was obtained by the following method. However, in order to apply the ultraviolet curing method to all models, there are the following problems. The first point is that it is difficult to cure the thick film with ultraviolet rays, and the parts that are not exposed to ultraviolet rays are hardly cured, so in order to obtain a completely cured product, it is necessary to heat cure in an oven for a long time, and the second point is For high-voltage models that require void-free treatment, ultraviolet irradiation alone will not completely prevent the impregnated resin from leaking, and a fairly long period of rotational heating is required until the resin gels. In addition, large-sized fills require a long time to raise the curing temperature, and even longer rotational heating is required. As a result, the rotation rate of the turntable deteriorates, and when the number of units produced increases, a large number of turntables are required, and the curing equipment becomes larger and more expensive.

This invention was made in order to improve the shortcomings of the conventional manufacturing method as described in -1-, and involves impregnating a bare coil with a resin composition or varnish that can form a film by irradiating it with ultraviolet rays. The object of the present invention is to provide an economical method for manufacturing resin-impregnated molded coils with good production efficiency by irradiating the coils with ultraviolet rays and microwaves.

Embodiments of the present invention will be described below with reference to the drawings.

Example 1 In Fig. 4 al], 1 is composed of an insulating base material such as polyester non-woven fabric, aramid paper, glass fiber, etc. and an insulated conductor such as heat-resistant enameled wire, polyester non-woven fabric winding, aramid winding, glass winding, etc. This is a high voltage cylindrical cable coil used in transformers, etc. 7 is a winding core, which may be made of metal such as iron or aluminum, or may be a round rod or tube made of plastic, as appropriate. Then, a resin composition consisting of epoxy resin and inorganic filler is coated and cured on one bare coil, or microwave-cured prepreg, aramid, polyester nonwoven fabric, thermosetting resin felt, and prepreg or microwave-cured prepreg of these. A leakproof layer 12 made of prepreg is formed. Thereafter, the coil 1 is impregnated with an epoxy resin composition 4 containing 30% by weight of a component that is cured by ultraviolet light and is a polyacrylate type monomer with a photosensitizer added. Thereafter, as shown in FIG.
When the coil surface layer is rotated in the direction 8 of the arrow in the figure at a rotation speed of M and irradiated with ultraviolet rays 9 in the 5-wavelength range of 300 to 40 (hμ) for 5 to 15 minutes using a high-pressure mercury lamp 3, the coil surface layer becomes several tens of meters thick. Appearance becomes a solid phase state, and leakage of the liquid impregnated resin contained inside the coil almost stops.However, in the case of large high-voltage molded coils that have a high resin content and tend to leak. If the coil is heated while standing still, the low-viscosity resin inside the coil may leak due to pinholes in the UV-cured coating or peeling of the UV-cured coating due to thermal expansion caused by heating.Therefore, as shown in Figure 4, The coil that has been irradiated with ultraviolet rays is placed in a microwave oven 13, and while being rotated by a rotating device 2, a microwave 14 having a wavelength of 30 cqo to 1 ean is irradiated.The microwave 14 has a frequency of 1
At 000MHz-3000100O, coil 1 instantly
The ultraviolet rays can penetrate into the skin and form a thicker and stronger solid phase coating in 10 seconds to 15 minutes than when using ultraviolet rays alone. Dielectric heating generates heat due to dielectric loss, and is proportional to the dielectric constant and dielectric loss tangent. For this reason, by selectively heating a low-viscosity liquid impregnated resin that has a high dielectric constant and dielectric loss tangent, and which tends to leak, to the inside, the film solidified by ultraviolet rays generates less heat and heats it evenly. , take it as two or something. This eliminates the need for rotating heating in an oven for 5 to 1 hours, and by post-heating in a normal standing state, a cedar fat-impregnated molded film with excellent leak-free electrical and mechanical properties can be created. or obtained.

Embodiment 2 In FIG. 5, reference numeral 6 denotes an electric stator coil, which, as shown in FIG. and an insulating base material 1 made of aramid paper, polyester film, etc.
8, etc., and is impregnated with an unsaturated polyester varnish containing a component that is cured by ultraviolet light, which is a polyacrylate type monomer added with a photosensitizer. As shown in FIG. 5, since this coil 6 is not rotated in the direction 8 of the arrow in the figure by a rotating device 15, the microwave 14 is transmitted from a microwave oscillator 16 through a waveguide 17 to 1, as in the first embodiment.
Irradiate for 0 seconds to 5 minutes. After the impregnated resin of the entire coil is semi-cured or almost completely cured, including the parts that are difficult to be exposed to ultraviolet rays, the ultraviolet 9 is irradiated with the high-pressure mercury lamp 3 for 10 seconds to 30 minutes. Resin-impregnated molded coils with excellent mechanical properties can be manufactured in an extremely short time.

In this invention, in Example 2 described in -F, ultraviolet light 9 was irradiated after irradiation with microwave 14, but in the case of a large model with a tendency to leak from impregnated resin, ultraviolet 9 was first irradiated, and then microwave 14 was irradiated.
When irradiated with 4, a coil with 1 better electrical properties can be obtained. Also, depending on the model, microwave 14 and ultraviolet 9
may be irradiated at the same time, and the method of rotating the coil may be changed arbitrarily.

Furthermore, in the case of a low-voltage model that may allow some varnish to leak, the rotation of the coil during irradiation with ultraviolet rays 9 or microwave 14 may be omitted. Furthermore, in order to eliminate leakage of the impregnated resin in high-voltage models, a semi-cured resin composition containing an ultraviolet curing component or an ultraviolet curing resin 11 composition is applied onto the insulating base material 18 or After forming the leakproof layer 15 impregnated into a semi-cured state, a coil with good electrical characteristics can be obtained by performing an impregnation treatment.

As explained above, according to the present invention, after impregnating the bare coil with an ultraviolet curable resin composition or an ultraviolet curable varnish or forming a leakproof layer as necessary, the resin described in 1. The coil is impregnated with a composition or varnish, and the coil is irradiated with ultraviolet rays and microwaves to harden the impregnated resin. There is an effect that the molded coil is removed during manufacturing.

[Brief explanation of drawings]

Fig. 1 is a partially sectional front view showing a conventional method for manufacturing a resin-impregnated mold transformer coil, Fig. 2 is a partially sectional front view showing a conventional method for manufacturing a stator coil for an electric motor, and Fig. 3 is a partially sectional front view showing a conventional method for manufacturing a stator coil for an electric motor. FIGS. 4A and 4B are cross-sectional views showing a method for manufacturing a motor stator coil, and FIGS. 5 is a partially sectional front view showing a method of manufacturing a motor stator coil according to another embodiment of the present invention, and FIG. 6 is a front view of a motor stator coil according to the embodiment of FIG. 2 of the present invention. It is a sectional view showing a slot part. 1...Transformer coil impregnated with ultraviolet curing resin composition 3...High-pressure mercury lamp 4...Ultraviolet curing (b1 fat m precept 6...Stator coil impregnated with ultraviolet curing varnish 9...Ultraviolet rays) 10... Stator coil impregnated with ultraviolet curable resin composition 12... Leakproof layer 14... Microwave Note that the same reference numerals in the drawings indicate the same or corresponding parts. Agent Shin Kuzuno - ( (1 person) 10- Spear 1 Figure 12 Figure ↓ Number ↓ ↓↓↓↓ Tode Figure 4 Procedural amendment (voluntary) 2 Name of the invention M Process for manufacturing a fat-impregnated molded coil 3. Relationship h・Applicant Address Marunouchi, Chiyoda-ku, Tokyo"-I'll 2
Number: 31. LP name (601) Tamabishi Electric Co., Ltd. Representative piece 111 Part 4, Agent 5゜Subject of amendment (1) Column for detailed explanation of the invention in the specification (2) Brief description of drawings in the specification Explanation column (3) Drawing 6° Contents of correction (1) In the detailed description, page 8, line 19, "leakproof layer 15" is corrected to "leakproof layer 12." (2) On page 10, line 1 of the same document, the phrase ``in Figure 2 of this invention'' is amended to read ``in Figure 5 of this invention''. (3) Amend Figure 1 of the drawing as shown in the attached sheet. (4) Amend Figure 4 of the drawing as shown in the attached sheet. 7゜ List of attached documents (1) Amended drawings 1 copy ljl Spear 4I! ! (J) /3

Claims (2)

[Claims] (1) After producing a bare coil, it is impregnated with an ultraviolet curable resin composition or an ultraviolet curable varnish,
After that, the coil is irradiated with ultraviolet rays and microwaves,
A method for manufacturing a resin-impregnated molded coil, which comprises curing the impregnated resin. (2) Ultraviolet rays of the bare coil are difficult to hit 1) and impregnated f1
2. The method for producing a resin-impregnated molded filler according to claim 1, wherein a leak-preventing layer made of a thermosetting resin material is formed on a portion where fat easily leaks, and then an impregnation treatment is performed.