JPS60219717A - Magnetic shield of stationary induction apparatus - Google Patents

Abstract

PURPOSE:To prevent infiltration of magnetic flux into a tank by removing the gap between adjacent magnetic shields forming the end of the magnetic shield in a recessed or a projected shape. CONSTITUTION:In a tank 4 made of a magnetic material housing a stationary induction apparatus, plural unit magnetic shields 15-7-15-10 laminated with magneto-conductive plates are installed. Each unit magnetic shield has plural recessions at one end of the longitudinal direction and plural projections which correspond to the recessions at the other end. By engaging the recession and the projection of the ends of the adjacent unit magnetic shields, the gap between the adjacent unit magnetic shields is removed and infiltration of magnetic flux into the tank 4 can be prevented.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a magnetic shielding device for a static inductor such as a transformer or an accelerator. - This relates to a magnetic shielding device for a stationary inductor equipped with a magnetic shield that shields from leakage magnetic flux.

[Conventional technology]

First, let's take a conventional external iron transformer, which is this kind of device, as an example.
This will be explained with reference to FIGS. 1 to 5. In Figure 1, the main body of the transformer, which consists of a high-voltage coil containing τ low-voltage coil coil and an iron core J, is housed in a tank 'IK', and the material of the tank is generally 581.
Steel materials indicated by 7/ are used. J-/~3-7 are magnetic shields provided to shield the tanker from leakage magnetic flux, and are attached by welding after the tanker is manufactured. Figure 2 shows the magnetic shield k −/−3
It is made by welding the seat plate C of -7. Figure 3 is an enlarged view of part A in Figure 1 to make it easier to understand how the unit magnetic shield is attached to the tanker.The magnetic shield is attached to the tanker by welding the seat plate j to the tanker. It is being

In the above configuration, the ideal flow of leakage magnetic flux caused by the winding 'iit flow is shown in Figure 1.

That is, in FIG. 1, φi, +12 is the leakage magnetic flux caused by the winding current. -/, φ is +5-/~φ
An ideal magnetic shield is one in which the flow is divided and flows through the magnetic shields j-7 to s-e, as shown by s-t, and does not enter the tank FIC. However, in reality, this does not happen, and magnetic flux also invades tank q. The mode and reason for this are explained in the third section.
This will be explained using figures. In Fig. S, I, /, and L are the inner dimensions of the tank, and L8/, and L8J are the lengths of the magnetic shield. Approximately, permissible manufacturing errors are required in the manufacturing of objects, and in consideration of this, the length of the magnetic shield L5z
, L+B are manufactured to be smaller than the dimensions calculated from the inner dimensions of the tank, L/ and L. For this reason, when the magnetic shield is attached to the tank QK, lyt, J-ga, 1
13. It is unavoidable that a void shown at 11g is formed. Since the magnetic permeability is low in these gaps, the magnetic flux is φf/, φ2 . Invade the tanker as shown by *pp.

The above +5K, with the conventional device ijK, na l /, φ
t1゜natJ, a loss occurs in the tank through which the magnetic flux passes, as shown by Ritei, and the so-called stray loss h''--increases.
Summary of the Invention The present invention aims to eliminate the drawbacks of the conventional device as described above and reduce stray loss. To provide a magnetic shielding device for a stationary inductor, which has a configuration in which these are interlocked and coupled.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. FIG. 6 shows a unit magnetic shield /j, which is made by shifting an appropriate number of magnetic thin plates /θ in the longitudinal direction and sandwiching them with scissors plates /7.

A plurality of concave portions /ja are formed at one end, and a plurality of convex portions isb corresponding to the concave portions / and taK are formed at the other end. /l is a seat plate for mounting, which is welded /9 to the scissor plate 77.

Figure 7 shows the state in which it is installed in the unit magnetic shield external iron type transformer shown in Figure 6, and /j-/~/j-IO are unit magnetic shields each having the shape shown in Figure 6. ,
They are interlocked with corresponding concave and convex portions. In order to better understand the aspect of this meshing, FIG. 1 shows an enlarged perspective view of section B in FIG. 7. Here, the dimensional relationship of the meshing part must be as follows. That is, in FIG. 9, let Ll be the internal dimension of the designated tanker, let its manufacturing tolerances be +J-t and -Ax, and let the number of engaging parts be n (n=ko in the figure), and a7. a + 1) / + b J
are the dimensions shown and a/+Il 〉 − .

〔Effect of the invention〕

As is clear from the above description, this invention has a simple structure that eliminates the air gap at the end of the single magnetic shield that could not be avoided in the past, prevents magnetic flux from entering the tank, and minimizes stray loss. It can be done.

[Brief explanation of drawings]

Figures 1 to S show a conventional device, with Figure 1 being a schematic sectional view of the main parts, Figure 1 being a partially perspective view, Figure 3 being a partially assembled perspective view, Figures 1 and 3. 2A and 2B are schematic cross-sectional views of main parts for explaining the functions, respectively. Figures 6 to d show an embodiment of the present invention, with Figure 6 being a partial perspective view, Figure 7 being a schematic sectional view of the main part, Figure 3 being a partially assembled perspective view, and Figure 3 being a partially assembled perspective view. FIG. 3 is a partial plan view for explaining dimensional conditions. 1111 + high voltage coil, low voltage coil, 3-・iron core, ≠・φ tank, /! ,/! L;-/~/! -10・
Fist unit magnetic shield, /4...Magnetic thin plate, /RiQ, scissor plate, /1...Seat plate. In each figure, the same reference numerals indicate the same or corresponding parts. Difference 1 Figure 2 Figure 3 Figure 4-j Figure 5 Figure 6 Figure Flame 7 Figure Figure 8 Flame

Claims (1)

[Claims] A magnetic shielding device for a stationary inductor, comprising a tank made of a magnetic material that houses a stationary inductor, and a magnetic shield that is made of a plurality of unit magnetic shields made of laminated magnetic thin plates and prevents magnetic flux from entering the tank, A magnetic shielding device for a static inductor, characterized in that the unit magnetic shield is provided with a plurality of recesses at one longitudinal end and a plurality of projections corresponding to the recesses at the other end.