JPS6244806B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transformer core tightening device, and in particular, to sufficiently tighten the leg core, yoke core, etc. of a transformer to firmly connect the coil and core. This relates to a tightening device for transformer cores.

In a transformer, sufficiently tightening the transformer cores, such as the leg core and yoke core, prevents the core from shifting due to the strong mechanical force generated in the coil during a short circuit, and also strengthens the coil and core. It is also extremely important to minimize the vibrations of the coil and iron core.

Conventionally, as this type of transformer core tightening device,
It was as shown in FIGS. 1 and 2. That is,
In an external iron type transformer T in which a leg core 1 and a yoke core 2 are stacked on a core receiving plate 4 in a tank 3, and a coil group 5 and a yoke 6 are coupled to this, the leg core 1 and the yoke After the stacking of these cores is completed, the section core 2 is tightened by a pair of fasteners interposed between the top surface of the leg section core 1 and the coil group 5, and between the top surface of the yoke section core 2 and the yoke 6. A metal wedge 9 is inserted between the attachment plates 7 and 8 by driving it in the direction of arrow A using the impact force of a hammer-like object to widen the width of the tightening plates 7 and 8.
The cores 1 and 2 were tightened by the spreading force of the wedge 9 against the wedge 8. 10 is a stop plate.

In the conventional transformer core tightening device as described above, there is a problem in that driving the wedge 9 is not desirable from a safety standpoint, and also generates a relatively large noise when driving the wedge 9.

In view of these circumstances, it is an object of the present invention to provide a transformer core tightening device that is extremely superior in terms of work safety, noise prevention, and stress relaxation characteristics of tightening force.

In order to achieve this object, the present invention utilizes the above-mentioned pair of tightening methods to replace the conventional wedge force used to spread the bag body, which is easily deformable and made of a metal material with high strength and high elastic modulus. An uncured thermosetting resin composition is inserted between the plates, and an uncured thermosetting resin composition is press-fitted into the bag body, the width is widened between the clamping plates, and a spreading force is applied to compress the iron core. It is characterized by being made by curing a thermosetting resin.

Hereinafter, the present invention will be explained with reference to one embodiment shown in the drawings.
The figure shows the tightening devices for each of the yoke cores 2.
Between a pair of clamping plates 7 and 8 interposed between the upper surface of the leg core 1 and the coil group and between the upper surface of the yoke core 2 and the yoke 6, a height plate made of a thin metal plate such as stainless steel or iron is provided. A bag 11 having high strength, high elastic modulus, and easy deformation is inserted, and a thermosetting resin composition 12 is press-fitted into the bag 11. 13 is a resin press-fitting device, which includes a tightening valve 14 and piping 15.
It is connected to the bag body 11 by.

Next, the operation of the above configuration will be explained with reference to the one shown in FIG. 3A. First, as shown in FIG. 7, 8 and bag 1
Attach 1 together. At this time, the bag body 11 is in a contracted state, and therefore, between the upper surface of the leg core 1 and the coil group 5, the bag body 11 and the tightening plate 7,
Since there is a sufficient space to allow the insertion of the screws 8 and 8, these can be easily attached from the direction of the arrow A in FIG. Thereafter, as shown in FIG. 4B, the resin press-fitting device 13 is operated to tighten the tightening valve 14,
The thermosetting resin composition 12 is press-fitted into the bag body 11 through the piping 15. In this way, the bag body 11 expands, and the leg core 1 is tightened by the pressure.

To tighten the yoke core 2, as shown in FIG. 3B, after inserting the bag 11 between the tightening plates 7 and 8,
is attached, and then the thermosetting resin composition 12 is press-fitted into the bag body 11.

When the uncured thermosetting resin composition 12 press-fitted into the bag body 11 is heated and cured as described above, a solid is formed in the bag body 11 and a tightening structure is completed. At this time, even if a pinhole occurs in the bag body 11, the thermosetting resin composition 12 does not leak like a normal fluid and the tightening force does not decrease, and compared to a fluid, the thermosetting resin composition 12 does not leak throughout the bag body 11. The structure is difficult to deform.

However, depending on the material of the bag body 11, the stress relaxation of the tightening force of the iron core differs. For example, if the bag is made of a flexible elastic material such as rubber, the 5A
As shown in the figure, the bag body 1 is smaller in width than the tightening plates 7 and 8.
6 receives the clamping pressure from the iron core as shown in FIG. 5B due to the press-fitting of the thermosetting resin composition 12, causing creep, and as a result, the clamping force against the iron core decreases. When the bag is made of a material such as rubber, there is a problem in that the thermosetting resin composition filled inside is required to have strong creep resistance. Excluded from this invention.

On the other hand, the bag body 11 of the present invention, which is made of a material with high strength and high elastic modulus such as an iron plate, has a cross-sectional length that decreases when the resin is injected under pressure, as shown in FIG. 4B. Expand without changing. The bag 11 that deforms in this way is made of a metal with a high elastic modulus, and unlike rubber, it does not easily creep, and even if pressure is applied and the bag 11 deforms, the volume of the bag 11 will decrease. Therefore, the volume of the resin inside the bag must be compressed, and the tightening force is unlikely to decrease.
As described above, the thermosetting resin used for the bag body 11 made of a material with high strength and high elastic modulus can function as a filler with any characteristics as long as it is crosslinked and made three-dimensional.

In addition, as the thermosetting resin composition 12, epoxy resin, polyester resin, or urethane resin is suitable.

Although the above embodiment uses a single bag 11, two or more bags 11 may be arranged side by side as shown in FIG. 6, and the same effect can be obtained.

As described above, according to the present invention, a transformer core can be tightened extremely effectively in terms of safety, noise prevention, and stress relaxation characteristics, and has significant industrial benefits.

[Brief explanation of the drawing]

Figure 1 is an elevational sectional view of the main parts of a conventional outside iron type transformer.
Figure 2 is a sectional view of Figure 1, 3A.
3B are elevational sectional views of essential parts of an embodiment of the present invention, FIGS. 4A and 4B are elevational sectional views for explaining the operation of the structure shown in FIG. 3A, and FIG. 5A,
Fig. 5B is an elevational sectional view for explaining the operation of things to be excluded from this invention, and Fig. 6 is an elevational sectional view of main parts of another embodiment of this invention. Identical or corresponding parts are designated by the same reference numerals throughout each figure. . 1...Leg part iron core, 2...Yoke part iron core, 4
...Lower core receiving plate, 5...Coil group, 6...
... Yoke, 7, 8 ... Tightening plate, 11 ... Bag body, 1
2...Thermosetting resin composition.

Claims (1)

[Scope of Claims] 1. An inclusion is inserted between a pair of clamping plates inserted between the upper surface of the leg core of the transformer and the coil group, and between the upper surface of the yoke core and the yoke, respectively. In the device that applies a clamping force to the iron core by widening the interval between the clamping plates, after press-fitting an uncured thermosetting resin composition into an easily deformable bag body made of a metal plate with high strength and high modulus, A tightening device for a transformer core, characterized in that the inclusion is a hardened material. 2. The transformer core tightening device according to claim 1, wherein a plurality of said inclusions are inserted.