JPH0367328B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an external iron transformer, and more specifically, it relates to a coil group in which flat coils are stacked, and a spacer piece that supports a coil conductor. , relates to an external iron type transformer consisting of an iron core in which thin plate iron core materials are stacked around the legs of a coil group.

[Conventional technology]

Figures 2 to 4 show conventional outside iron type transformers.
An insulating plate 2 is inserted between the flat coils 1 and between the flat coil 1 and the iron core, and a plurality of spacing pieces 3 for supporting the conductors of the flat coil 1 are attached to the insulating plate 2. The iron core 4 is made up of a coil plane side iron core 4a and a coil axial side iron core 4b, and is supported and housed in a tank 6 with a wedge 5 for tightening and fixing the coil group.

To assemble the external iron type transformer having the above configuration, a predetermined number of flat plate coils 1 are stacked, and insulating plates 2 are arranged between each coil and between the coil and the iron core.
A spacer piece 3 is interposed between the coils in the insulating plate 2 to counteract the electromagnetic force acting on the coil conductor. The electromagnetic force referred to here is a large force generated by an overcurrent flowing through the coil due to a ground fault or short circuit, and is generated in the direction in which the coils are stacked, that is, in the axial direction of the coils.

Next, thin plate iron core materials are stacked around the legs of the coil group assembled as described above to form the iron core 4.

With the above configuration, the electromagnetic force is transmitted to the iron core 4 via the spacing piece 3 and the insulating plate 2, and is supported by the iron core 4.
For this purpose, the iron core 4 is made by stacking the coil surface direction side iron core 4a and the coil axial direction side iron core 4b one on top of the other, and firmly tightening them with wedges 5, tanks 6, etc., so that the electromagnetic force of the coil is transferred to the core facing the coil surface. Even if it is transmitted to 4a, the frictional force of the overlapping part (overlapping area x number of overlapping surfaces x tightening surface pressure x friction coefficient)
Therefore, the iron core 4 is configured so that no misalignment occurs.

This iron core 4 is made by laminating thin plates for the purpose of reducing iron loss, but the number of sheets stacked at one time is generally multiple (usually 2 to 3) from the viewpoint of workability such as stacking time and ease of stacking. It is becoming.

However, in the invented transformer with a large electromagnetic force, one way to increase the frictional force is to increase the number of overlapping surfaces by reducing the number of layers stacked at one time (1
stacking sheets, etc.). Conventionally, this means of reducing the number of sheets stacked at one time was carried out over the entire area from the bottom end to the top end of the stack of iron cores 4.

[Problem that the invention seeks to solve]

In conventional external iron type transformers such as those mentioned above, the core is weak and difficult to stack, and since the number of stacks is large, it takes more time to stack, compared to the conventional transformer that stacks a large number of pieces at one time, making it less economical. There was a problem with the lack of.

This invention was made to solve this problem, and is an external iron type transformer that secures the frictional force of the iron core against the electromagnetic force of the coil, and improves workability and economic efficiency without causing the core to shift. The purpose is to obtain.

[Means for solving problems]

The outer iron type transformer according to the present invention reduces the number of stacked pieces at one time only in the range facing the spacer pieces arranged on the coil surface (the range where electromagnetic force acts on the core) in the laminated direction of the iron core, and In the area where the two do not face each other (the area where electromagnetic force does not act), the number of sheets stacked at one time is increased considering workability.

[Effect]

In this invention, without reducing performance,
Improves assembly workability.

〔Example〕

FIG. 1 shows an embodiment of the present invention, and is a diagram corresponding to FIG. 4.

Unless the insulating plate 2 between the coil and the core is very thick and has great rigidity, the electromagnetic force acting on the flat coil 1 is transmitted to the core only in the area where the spacers 3 face each other, and the electromagnetic force is transmitted to the core only in the area between the spacers 3. No force acts on . This was also confirmed by the results of experiments in which a force exceeding the frictional force was generated in a full-scale transformer and the misalignment of the iron core was observed.

As a result, in the conventional structure, the unnecessary process of reducing the number of thin iron core materials stacked at one time until the part where electromagnetic force does not act was performed, but this invention eliminates this and originally Reduce the number of sheets stacked at one time (increase the number of overlapping surfaces) only in areas where force is transmitted and frictional force is required, and in areas that do not face the spacing piece 3, reduce the number of sheets stacked at one time up to the number that can be stacked at one time in terms of magnetic properties. Do more.

As described above, since the number of stacked thin iron core materials in the portions not facing the spacing pieces 3 is increased, the assembly work efficiency is improved. For this purpose, in the insulating plate 2 on the core side of the insulating plate 2, the position of the spacing piece 3 to be placed on the core side of the insulating plate 2 on the coil side is marked in advance during the component manufacturing stage, and the position of the spacing piece 3 to be placed on the coil side is Sometimes you can use the marking line as a guide to change the number of sheets stacked at one time.

〔Effect of the invention〕

As is clear from the above description, this invention
With a simple structure in which the number of core materials stacked at one time is changed depending on the positional relationship of the spacing pieces, workability and economic efficiency can be improved without deteriorating performance.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a main part of an embodiment of the present invention, FIG. 2 is a side cross-sectional view of a part of a conventional external iron transformer, and FIG.
The figure is a cross-sectional view taken along the line - in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line - line in FIG. 3. 1... Flat plate coil, 3... Spacing piece, 4... Iron core. In each figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A coil group formed by stacking flat coils, a plurality of spacing pieces arranged on the plane part of each of the flat coils forming this coil group to support the coil conductor, and a thin plate around the legs of the coil group. In an external iron type transformer equipped with an iron core formed by stacking iron core materials, the number of sheets of the thin iron core material stacked at one time is greater in a portion not facing the spacing piece than in a portion facing the spacing piece. An external iron type transformer, characterized in that the above-mentioned iron core is provided with a joint portion formed by overlapping joints.