JPS62124706A - Water cooled winding for electromagnetic stirrer - Google Patents

Abstract

PURPOSE:To attain excellent mechanical rigidity, water-proof characteristic and long-life by winding porous polyamide fiber which assures easy impregnation of resin to the wound flat type wire to which the heat resistant enamel is baked, impregnating it with epoxy resin and then hardening the resin. CONSTITUTION:A porous polyamide fiber which assures easy impregnation of resin is wound as the main insulation layer to the wound flat type wire where the heat resistant enamel is burned as the turn insulation layer and then impregnating it with epoxy resin. A polyamide fiber being used should assure desirable air transmission of 25-20sec/100cm<3> of air. When air transmission exceeds 25sec/cm<3> of air, the resin holding property is deteriorated and resin may leak therefrom. As the resin to be impregnated to the winding, the epoxy resin consisting of bisphenol type epoxy, reactive reduction agent for example diglysidilether system reactive reduction agent and amine system hardening agent can be used desirably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a water-cooled winding used in an electromagnetic stirring device.

[Prior Art] Since electromagnetic stirring devices are installed in narrow spaces, they need to be designed to be compact in size. In addition, since there are cases where a large current is passed through the device, it is necessary to cool parts that become overheated, such as the windings, that is, the coil. In the case of an electromagnetic stirring device in which the coil is cooled by air, generally 3 to 5 A
It can be used at a maximum current density of up to about 10 A/+ui", but cannot be used when the maximum current density exceeds 10 A/w".
In such cases, an electromagnetic stirring device with a water-cooled coil is used.

FIG. 1 is a cross-sectional view of the winding portion of the water-cooled electromagnetic stirring device of the present invention, and FIG. 2 is an enlarged cross-sectional view of the coil in the device of FIG. The structure of the line part is based on the prior art, for example, Japanese Patent Publication No. 53-252.
Since the structure is the same as the winding part in the water-cooled electromagnetic stirring device described in Publication No. 35, the winding part in the water-cooled electromagnetic stirring device described in this publication will also be explained with reference to FIGS. 1 and 2. do.

In Fig. 1, (1) is a coil constituting a winding in which electric wire is wound into an oval shape, and this coil (1) has an iron core (2
) is inserted and fixed to the iron core (2) with a wedge (3) and a spacer (4). The coil (1) fixed to the iron core (2) is integrally impregnated with resin for insulation.

In FIG. 2, (5) is a conductor formed with necessary turns, such as a rectangular electric wire. For example, a polyimide film is wound several times in a half-overlap manner on the surface of the conductor (5) to form a turn insulation M (6). Further, on the upper layer of the turn insulating layer (6), for example, a glass tape is wound around the conductor (5) in two and a half turns, and the insulating layer (7
) is formed as the main insulating layer.

In the case of a conventional water-cooled electromagnetic stirring device, a turn insulating layer (
6) must be an insulating material with good water resistance,
It is necessary that the insulating layer (7) also serves as the main insulating layer in the case of air cooling. Therefore, in this case, the insulating layer (7) plays the role of bundling each turn conductor (5), and also has the function of covering the role of main insulation, that is, waterproof insulation, which is also performed by the turn insulating layer (6). The role of the insulating layer is changed, and the load on the turn insulating layer increases.

[Problems to be Solved by the Invention] In the winding of the conventional electromagnetic stirrer as described above, the turn insulating layer (6) is water resistant and provides insulation not only between coil turns but also across the entire coil turn. Since it is necessary to play the role of (main insulation), it has the disadvantage that it becomes thicker and the coil as a whole becomes larger. Furthermore, since the wire is formed into a coil by winding multiple layers of film to form an insulating layer, it is susceptible to deterioration due to processing, resulting in a shortened lifespan of the coil (1). On the other hand, if the turn insulating layer (6) is applied after forming the electric wire, the work is complicated and requires a large number of man-hours, which is disadvantageous economically.

This invention was made to solve these problems, and the finished size of the coil is small, and compared to conventional devices, it has excellent water resistance, long life, and excellent mechanical rigidity. The purpose of this invention is to obtain a water-cooled winding for an electromagnetic stirring device.

[Means for Solving the Problems] The water-cooled winding for an electromagnetic stirring device according to the present invention includes a rectangular electric wire winding on which heat-resistant enamel is baked as a turn insulating layer.
A porous polyamide fiber that can be impregnated with resin is wound as the main insulating layer, and this winding is further impregnated with an epoxy resin.

[Function] In this invention, polyamide fiber in a porous state that is easily impregnated with resin is wound around a winding made of rectangular electric wire baked with heat-resistant enamel, and this is impregnated with epoxy resin and hardened. Because of this, it has strong mechanical rigidity, excellent water resistance, and a long lifespan.

As the heat-resistant enamel used in this invention, polyester enamel, polyesterimide enamel, polyamide enamel, or polyimide enamel can be used, and can be selected depending on heat resistance.

The polyamide fiber used in this invention preferably has an aeration rate of 25 to 20 seconds/100c+a-air.If the aeration rate exceeds 25 seconds/7cm''-air, the resin retention will be poor and the resin will This is not preferable because it will leak, and this polyamide fiber has a thickness of 0.08+am (
3 mil>te area coefficient 40-60g/-2 or thickness 0.
13m+* (5 mil) and area coefficient is 70-90g/
m 2 can be suitably used, and polyamide paper can also be used.

As the epoxy resin to be impregnated into the winding wire, an epoxy resin consisting of a bisphenol type epoxy, a reactive diluent such as a diglycidyl ether type reactive diluent, and an amine type curing agent can be suitably used.

[Example] In Fig. 1, a rectangular electric wire is used as the conductor (5),
Polyester imide enamel is baked onto this rectangular wire to form a turn insulating layer (6).The conductor (5) is wound into a coil the required number of times and formed into the desired shape, followed by a main insulating layer (7). Ventilation with an area coefficient of 81.4g/portion 2!
25 seconds/LOQc theory below air (ASTM D72
A tape made of polyamide paper having a density of 6A method) with a thickness of 0.13+*s (5 mils) and a width of 191 mm was wrapped around the above coil four and a half times.
The iron core (2) shown in the figure was inserted, fixed using wedges (3), spacers (4), etc., and wire connections were made. Turn insulation and main insulation are performed on this connection part in the same manner as above, and further, this coil (1) is impregnated with vacuum pressure and pressure using an epoxy resin consisting of bisphenol type epoxy, a reactive diluent, and an amine hardening agent. The impregnated resin was polymerized and cured while rotating drying.

Experiments were conducted to examine the deterioration characteristics of the coils made in this way when applied with electricity in water. In this experiment, when a coil is immersed in water and a voltage is applied, the deterioration characteristics are determined from the relationship between the applied voltage and the time until the coil becomes punctured. The results obtained in this way are shown in FIG. 3, where curve A is for the coil according to the present invention and curve B is for the conventional coil. In the coil according to this invention, 200
The coil was punctured in 2×10' hours when ① was applied, and in 1×10' hours when 1000 V was applied. Therefore, it can be seen that the deterioration characteristics of the coil according to the present invention are far superior to those of conventional coils. This is considered to be because the main insulating layer (7) of the present invention is extremely dense, so that the water resistance and the deterioration due to the application of electricity are considerably improved. Therefore, compared to the conventional structure in which each turn insulating layer (6) has water resistance, it has far superior reliability.

In the above example, an epoxy resin consisting of bisphenol epoxy, a reactive diluent, and an amine curing agent was used as the impregnating resin, but the main insulating layer had an air flow rate of 25 seconds/
As long as a porous polyamide paper of 100+*'-air or less is used, the same results as above can be obtained using other epoxy resins.

Further, in the above embodiment, polyesterimide enamel rectangular winding wire was used, but polyester enamel, polyamide enamel, polyimide enamel rectangular wire, etc. may also be used depending on the difference in heat resistance.

In addition, on the upper layer of polyester imide enamel flat wire,
It is also possible to prevent processing deterioration by applying a glass-wrapped layer as a complete measure.

[Effects of the Invention] As explained above, this invention can be applied to polyester enamel, polyesterimide enamel, polyamide enamel,
and polyimide enamel on a winding of a rectangular electric wire baked as turn insulation,
Air flow rate: 25 seconds/100 Cffl'' - A polyamide fiber of less than air is wound as the main insulation, and the winding with the main insulation is impregnated with an epoxy resin consisting of bisphenol-type epoxy, a reactive diluent, and an amine-based curing agent. By being hardened, the turn insulating layer is strong and has excellent water resistance, and an inexpensive water-cooled winding for an electromagnetic stirrer can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a winding part in a water-cooled electromagnetic stirring device according to an embodiment of the present invention, and at the same time, a sectional view of a winding part in a conventional water-cooled electromagnetic stirring device. The enlarged sectional view of the coil, FIG. 3, is a line section showing the underwater charging deterioration characteristics of a coil used in an embodiment of the present invention or a conventional water-cooled electromagnetic stirring device. In the figure, (1) is a coil; (2) is iron core, (3) is wedge, (4) is spacer, (5) is conductor, (6)
is a turn insulating layer, and (7) is a (main) insulating layer.

Claims (1)

[Claims] A winding of a rectangular electric wire with an enamel selected from the group consisting of polyester enamel, polyester imide enamel, polyamide enamel, and polyimide enamel baked as turn insulation, with an air flow rate of 25 seconds/100 cm^3
- sub-air polyamide fibers are wound as the main insulation;
Bisphenol type epoxy is applied to the winding with the main insulation.
A water-cooled winding for an electromagnetic stirring device characterized by being impregnated with and hardened with an epoxy resin consisting of a reactive diluent and an amine hardening agent.