JPS603543Y2 - molded coil - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a molded coil that is used in static induction equipment such as a transformer and is insulated with a resin mold.

Conventional methods for forming molded coils include immersing a wound coil in a resin solution bath to impregnate the inside of the coil with resin, then taking it out and curing the resin, or forming the coil in a molding mold. A method is used in which the resin is stored in a mold and resin is injected into the mold to harden it.

However, in the former case, when the immersed coil is removed from the resin solution bath and cured, the resin solution impregnated inside the coil flows down before it hardens, creating voids inside the coil and reducing insulation and moisture resistance. be.

In the latter case, one molding die is usually required to form one molded coil, and since coils differ in size and shape depending on various required ratings and specifications, it is necessary to use a variety of molding dies. Even for molded coils of the same size and shape, it is necessary to have a large number of molding molds during mass production, which increases the manufacturing cost of molding molds and their depreciation costs, which is uneconomical. be.

Moreover, it takes a lot of effort to work with molds, such as storing and taking them out from the mold, and it is necessary to take care not to damage the insulation material on the coil surface during this work, and to make it easier to operate. In addition, the size of the mold is made larger, and therefore the resin layer of the molded bottom coil becomes thicker than necessary, leading to an increase in the amount of resin used and resulting in high costs.

The purpose of the present invention is to eliminate the above-mentioned drawbacks and provide a molded coil with excellent insulation and moisture resistance without using a molding die.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 is an insulating tube formed by winding an insulating sheet material.

This is a product impregnated with so-called semi-curing resin, which is obtained by impregnating a fibrous base material such as glass cloth with a resin material such as epoxy resin or polyester resin and curing it to a semi-cured state (B stage). Insulating sheet materials such as (name) and prepreg (trade name of Krempel) are used.

2 is an interlayer insulating material made of an insulating sheet material such as glass nonwoven fabric or polyester nonwoven fabric with good resin impregnation properties.

3 is a foil-like or linear conductor made of a highly conductive material, and 4 is an impregnated resin such as epoxy resin or polyester resin.

This impregnated resin 4 is selected from a resin material of the same type as the semi-hardened resin impregnated into the insulating cylinder 1.

Reference numeral 5 denotes an outer insulating material made of an insulating sheet material similar to the interlayer insulating material 2 described above.

An elementary coil A is formed by these.

Reference numeral 6 denotes a sheathing member that covers the outer circumferential surface and upper and lower end surfaces of the elementary coil A.

A sheet metal foil material such as aluminum foil is used for this jacket member, and the jacket member 6, which is wider than the raw coil A, is removably wound around the outer periphery of the raw coil A, and both ends in the width direction are bare. Coil A
It is bent inward along the upper and lower end surfaces of the insulating cylinder 1, and further covers the upper and lower ends of the insulating cylinder 1, overlapping and closely fitting the side wall.

Reference numeral 7 denotes an adhesive tape for sealing, which is adapted to removably attach and seal both ends of the outer covering member 6 in the width direction to the side wall of the insulating cylinder 1.

Reference numerals 8 and 8' designate injection holes and discharge holes which are opened in the outer cover member 6 on the upper end surface of the elemental coil A and communicated with the inside of the elemental coil A.

Reference numerals 9 and 9' designate an injection pipe and a discharge pipe for injecting the impregnated resin 4 into the injection hole 8 and the discharge hole 8'.

Next, formation of the molded coil will be explained.

First, an elementary coil A is formed. This is made by winding an insulating sheet material impregnated with a semi-curing resin around a winding form (not shown).
The conductor 3 is wrapped thereon with the interlayer insulating material 2 made of an insulating sheet material such as glass non-woven fabric, and wound the required number of times. Turn to form elementary coil A.

A jacket member 6 whose inner surface is coated with a mold release agent is wound around the outer peripheral surface of the bare coil A thus formed, and the winding ends are sealed with adhesive tape or the like.

Then, both ends of the outer covering member 6 in the width direction are bent inward along the upper and lower end surfaces of the elementary coil A, and further bent to cover the upper and lower ends of the insulating tube 1 and overlap the side walls. The outer circumferential surface and upper and lower end surfaces are covered with an outer covering member 6.

Thereafter, both side edges of the jacket member 6 are brought into close contact with the side walls of the insulating cylinder 1 using adhesive tape 7 to seal them.

Then, an injection hole 8 and a discharge hole 8' are bored in the jacket member 6 on the upper end surface of the elemental coil A to communicate with the inside of the elemental coil A.

Next, the impregnated resin 4 is injected into the elementary coil A through the injection hole 8.

One or more elementary coils A covered with a jacket member 6 are stored in a vacuum drying tank equipped with a heating device (not shown), and an injection pipe 9 and a discharge pipe 9 are inserted into an injection hole 8 and a discharge hole 8'.
' are respectively established with putty or the like and connected to the injection pipe 9 via a supply pipe from a mixing tank (not shown) containing impregnated resin 4, and in this state, the raw coil A is heated by a heating device provided in the vacuum drying tank. do.

By this heating, the moisture inside the elementary coil A is dried, and the semi-hardening resin impregnated into the insulating tube 1 is hardened by heating.

Next, the pressure inside the vacuum drying tank is reduced (vacuumed), and the liquefied impregnated resin 4 is injected into the elementary coil A through the injection hole 8 from the mixing tank.

The injected impregnating resin 4 permeates the interlayer insulating material 2 with good impregnability, is degassed from the discharge hole 8', and is impregnated into every corner of the element coil A without forming any voids.

At this time, since the inside of the elementary coil A is covered by the outer cover member 6 and the insulating cylinder 1, the impregnated resin 4 is injected without leaking outside.

When the impregnating resin 7 is sufficiently injected into the inside of the elementary coil A, the resin injection is stopped, and the inside of the vacuum drying tank is returned to normal pressure and heated.

When the impregnated resin 4 is in a gel state, the injection pipe 9 and the discharge pipe 9' established in the injection hole 8 and the discharge hole 8' are removed, and after being cured by heating, the outer cover member 6 and the adhesive tape 7 are removed.
Form a molded coil.

As described above, in the present invention, a conductor is wound around an insulating tube impregnated with a semi-hardening resin with an interlayer insulating material sandwiched therebetween to form an elementary coil, and the outer peripheral surface of this elementary coil has a width larger than that of the elementary coil. An outer covering member made of a wide metal foil material is removably wrapped around the outer covering member, and both ends of this outer covering member are bent inward along the upper and lower end surfaces of the bare coil, and the bent ends are overlapped with the side walls of the insulating cylinder. Then, the outer sheath member is opened to provide an injection hole in the upper end surface of the element coil, and the impregnated resin is injected through the injection hole and cured, and the outer sheath member is removed to form a molded coil. Since the bare coil is wrapped with an outer sheathing member made of metal foil material, it is possible to wrap the coil along the shape of the bare coil. The resin jacket can be formed without making it thicker than necessary, and the amount of resin used can be reduced compared to the case where a mold is used.

Furthermore, since the resin is injected into the bare coil covered with the outer sheathing member, there is no need to take the coil in and out of the mold, thereby reducing the number of man-hours.

Furthermore, since the outer sheathing member is detachably attached to the bare coil, it can be reused by peeling it off after the resin has hardened, and it can also be used even if the raw coil has a different size and shape.

This has a remarkable effect especially on high-mix, low-volume production.

Moreover, since the outer covering member is made of a metal material, the surface of the resin outer covering after peeling can be made smooth and beautiful, and the commercial value can be increased.

Furthermore, since a mold is not used, the degree of freedom in designing the coil can be expanded and efficient design can be performed, and there is an advantage that an economical molded coil can be formed.

[Brief explanation of the drawing]

The figure is a partially cutaway perspective view of an embodiment of the present invention. 1: Insulating cylinder, 2: Interlayer insulation material, 3: Conductor, 4: Impregnated resin, 6: Covering member, 8: Injection hole.

Claims (1)

[Scope of utility model registration request] A conductor is wrapped around an insulating tube impregnated with semi-hardened resin with an interlayer insulating material made of glass non-woven fabric sandwiched between them to form a bare coil, and a metal foil material wider than the bare coil is wrapped around the outer circumference of the bare coil A sheet-like outer sheathing member made of the above is wound, and both widthwise ends of the outer sheathing member are bent inward along the upper and lower end surfaces of the bare coil, and the bent ends are overlapped with the side walls of the insulating cylinder and sealed. An injection hole and a discharge hole are formed in the jacket member on the upper end surface of the element coil, and an impregnated resin is injected through the injection hole and cured.