JPH0574634A - Transformer - Google Patents

Abstract

PURPOSE:To improve transformer performance without a special working process on a junction surface, in a transformer using a block iron core, and reduce the manufacturing cost of a transformer. CONSTITUTION:Magnetic air gaps 10 having a width of 0.05-0.8mm are arranged on the junction end surfaces of leg members 1b, 1d and yoke members 1a, 1c. Thereby the no-load loss is drastically reduced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to transformers, and more particularly,
The present invention relates to a transformer that is easy to assemble and has little no-load loss.

[0002]

2. Description of the Related Art A conventional transformer generally uses a single-wrap type iron core as shown in FIG.

This transformer using a single-wrap type iron core has a leg member c on both ends of an iron plate b for a yoke member a.
The iron plates d for use are alternately stacked one by one, and the yoke member a and both leg members c and c are formed into a U shape, and then the leg members c and c are loaded with the coil e. , C, the iron plates g for the iron core of the yoke member f are inserted one by one to assemble. For this reason, a lot of manpower is required for assembly, and the manufacturing efficiency is very poor.

Therefore, in order to solve such a problem of assembling the transformer, the inventor of the present application has devised a block iron core for a transformer in which iron plates for an iron core are laminated to form a block.

The transformer using the block iron core can be assembled by simply abutting the ends of the block iron cores and joining and fixing them with a fixing frame. Therefore, as in the conventional case, one iron plate for iron core is used at the assembly stage. There is no need to stack them alternately, and the assembly work efficiency can be greatly improved.

[0006]

However, the iron plate used for the block iron core is usually 0.1 m when it is cut.
An error of about m occurs, and when hundreds of iron plates are superposed and laminated, unevenness due to a processing error occurs at the end thereof. For this reason, it is not possible to secure a smooth joint surface, and the magnetic resistance of the contacted portion and the non-contacted portion of the joint is not constant, which increases the no-load loss of the transformer. ing.

For this reason, in order to bond the joint surfaces of the block cores in a close contact state and suppress no-load loss, the machining accuracy at the time of cutting is increased, and after the block cores are formed, the joint surfaces are processed again. This is also a cause of increasing the cost of the transformer using the block iron core.

The present invention solves the above-mentioned problems of a transformer using a block iron core, improves the transformer performance without applying special processing to the joint surface, and further, reduces the manufacturing cost of the transformer. The purpose is to reduce

[0009]

[Means for Solving the Problems] Generally, it is considered that contacting each joint surface of the block iron core with each other further improves the transformer performance. Various measures have been taken. However, the inventors of the present application have conducted various experiments in order to improve the transformer performance, and it is found that the transformer performance is improved by providing an appropriate gap rather than joining the block cores in a close contact state. I found out. The present invention has been completed based on this finding.

That is, the transformer of the present invention is a transformer provided with a transformer iron core formed by joining and fixing each end surface of a leg member and a yoke member, which are formed by bundling laminated iron plates for an iron core by a tying means. In the container, a magnetic gap having a width of 0.05 to 0.8 mm is provided on the joint end surface of the leg member and the yoke member.

[0011]

FIG. 3 is a graph showing the relationship between the gap width of the magnetic gap formed on the block core joint surface and the no-load loss.

In the figure, the broken line indicates the frequency 5.
0H _Z , no load loss (W / unit) when the maximum magnetic flux density is 1.7 Tesla, and the solid line shows the frequency 50 H _Z ,
No-load loss at maximum magnetic flux density of 1.5 Tesla (W / un
It) is shown. As shown in the figure, there is a clear correlation between the gap width and the no-load loss, and the average value of the gap width forming the magnetic gap is about 0.05 to 0.8 mm.
In the range, the no-load loss is reduced as compared with the conventional single lap type, and the effect is particularly remarkable in the range of 0.1 to 0.3 mm.

When processing the iron plate for the iron core, it is usually 0.
Although a processing error of about 1 mm occurs, in the transformer of the present invention, this processing error falls within the above-mentioned gap width, so that the conventional iron core plate having a processing error can be used as it is.

[0014]

EXAMPLES The present invention will be described in detail with reference to the examples shown in the drawings.

FIG. 1 is a plan view of a transformer according to an embodiment of the present invention, and FIG. 2 is a perspective view of a transformer core used in the transformer of FIG.

The transformer core 1 comprises yoke members 1a and 1c.
, Leg members 1b and 1d, 5 is a fixed frame for fixing the yoke members 1a and 1c and the leg members 1b and 1d, and 8 is a coil wound around the leg members 1b and 1d.

The yoke members 1a and 1c and the leg member 1
As shown in FIG. 2, b and 1d are block iron cores in which a large number of iron core iron plates 2 having substantially the same shape and dimensions are laminated and bound by a binding means such as a glass tape 3 to form a block.

As the iron plate 2 for the iron core, an electromagnetic steel plate having a large magnetic permeability and a small iron loss and a thickness of 0.23 mm to 0.35 mm is used, and the yoke members 1a, 1c and the leg member 1 are used.
Tapered portions 4 are formed at both ends of b and 1d so as to form a right angle in the joined state.

The fixed frame 5 joins and fixes the yoke members 1a, 1c and the leg members 1b, 1d from the outside.
It comprises a U-shaped member 5a and an I-shaped member 5b used in combination therewith. Fixing means such as bolts 6c for fastening the U-shaped member 5a to both ends of the I-shaped member 5b, and joining of the yoke members 1a, 1c and the leg members 1b, 1d to the four corners of the U-shaped member 5a. Bolts 6 for pressing and fixing parts
Fixing means such as a and 6b are provided. Furthermore, this bolt 6
Pressing members 7a and 7b are provided at portions where a and 6b come into contact with the transformer core 1 in order to avoid concentrated loads. 9
Are grooves for shifting the iron plate 2 for the iron core 2 in the outward direction when there is a manufacturing error, and are provided at the four corner tips of the iron core 2 for the transformer.

The yoke members 1a and 1c and the leg member 1
Spacers 10 that form magnetic gaps for reducing no-load loss are loaded on the joint end surfaces b and 1d. As the spacer 10, a predetermined gap is secured,
In addition, any material that is non-magnetic and electrically insulating may be used, but, for example, kraft paper or synthetic resin plate having excellent insulating properties can be used.

In this embodiment, the inner iron type single-phase transformer has been described, but it is needless to say that the present invention is not limited to this, and it is also possible to use it for an outer iron type or a three-phase transformer. It is also possible to employ a so-called strip-shaped block core in which both ends of the core are not tapered.

[0022]

As described above, in the transformer of the present invention, the magnetic gap is provided at the joint end face between the leg member and the yoke member. For this reason, it becomes possible to reduce the no-load loss without requiring a special processing treatment for bringing the joint surfaces into close contact as in the conventional case. Further, since the conventional iron plate for an iron core having a processing error can be used as it is, the cost of the iron core for a transformer can be significantly reduced. Furthermore, as compared with the transformer using the conventional single wrap type iron core, the assembling work efficiency is improved 3 to 5 times.

[Brief description of drawings]

FIG. 1 is a plan view showing a transformer according to an embodiment of the present invention.

2 is a perspective view of an iron core used in the transformer of FIG. 1. FIG.

FIG. 3 is a graph showing the relationship between the gap width of the joint surface of the block core and the no-load loss.

FIG. 4 is a perspective view of a conventional transformer.

[Explanation of symbols]

 1 transformer iron core 1a, 1c yoke member 1b, 1d leg member 2 iron core iron plate 3 tape (bundling means) 4 taper portion 5 fixing frame 6 bolt (fixing means) 7 pressing member 8 coil 9 groove 10 spacer (magnetic gap)

Claims (1)

[Claims] 1. A transformer provided with a leg member in which laminated iron plates for an iron core are bound by a binding means to form a block, and a transformer iron core formed by joining and fixing each end surface of a yoke member, the leg member being A transformer characterized in that a magnetic gap having an average width of 0.05 to 0.8 mm is provided on a joint end face with a yoke member.