JPH10106845A - Tank for electrical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an inexpensive tank for electrical equipment having a high mechanical strength and a light weight. SOLUTION: In a tank for electrical equipment provided with a corrugated heat radiating plate 1 formed by continuously bending a thin steel sheet so as to form a wavy projecting section and airtightly attaching both ends of the projecting section to each other and upper and lower side plates 3 and 4 respectively joined to the internal surface of the plate at upper and lower ends, a reinforcement 8a is installed to either the upper side plates 3 or lower side plate 4 so that a hollow cross section can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tank for electric equipment which is provided with side plates at upper and lower ends of a corrugated radiator formed by continuously bending a sheet-like thin steel plate to form a wavy projection. It is also about.

[0002]

2. Description of the Related Art In general, in electric equipment, heat generated in a main body of the electric equipment contained in a tank is radiated from the surface of the tank through a cooling medium such as liquid or gas sealed in the tank. . For this reason, as a means for increasing the heat radiation capability of a tank of an electric device, a structure is used in which a side plate constituting the tank is bent into a waveform to increase the heat radiation area of the side plate itself.

FIG. 10 is a perspective view showing an example of a conventional electric equipment tank. In FIG. 10, reference numeral 1 denotes a projection 1a formed by continuously bending a sheet-like thin steel plate.
Is a corrugated heatsink having: This corrugated heat sink 1 is shown in FIG.
As shown in FIG. 2, after the wavy projections 1a are continuously formed at predetermined intervals, as shown in FIG. 12, the upper and lower open ends are pressed against each other to weld the welded portion 1b. FIG. 13 is a perspective view of the corrugated heat radiator plate 1 formed as described above.
A space 2 for enclosing the cooling medium is formed.

[0004] Next, as shown in the sectional side view of FIG.
The upper side plate 3 having the flange 3a is welded to the upper end of the corrugated heat sink 1 and the lower side plate 4 having the bottom plate 5 is welded to the lower end. As a result, a side plate of the tank also serving as the corrugated heat radiating plate 1 is obtained, and this side plate is provided on the entire surface to constitute a tank, or as shown in FIG.
The tank is composed in combination with When used as a tank for electric equipment, a lid is fixed to the flange 3a surface of the upper side plate 3 via a packing or the like.

[0005] By the way, electric equipment tanks are subject to temperature changes due to fluctuations in ambient temperature or fluctuations in load.
The cooling medium sealed in the tank expands and contracts to apply pressure. With the rise of the internal pressure, the wave radiator 1, the upper side plate 3 and the lower side plate 4 constituting the tank expand and deform as shown by a dashed line in FIG. Then, when the ambient temperature is reduced or the load is light, the internal pressure of the tank is also reduced, so that the tank shape returns to the original state shown by the solid line in FIG.

[0006]

However, the fluctuations in the ambient temperature and the load are repeated many times during the life of the electric equipment. As a result, as shown in FIG.
A1 between the upper side plate 3 and the lower side plate 4 is fatigued by repeated deformation due to a change in pressure in the tank, and eventually cracks may occur, preventing normal operation of the electric device. For this reason, it is necessary to increase the plate thickness of each member constituting the tank, but this leads to an economic disadvantage or an increase in product weight, and the wave-shaped heat sink 1
There was a problem that it became very difficult to fabricate.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an inexpensive and lightweight tank for electric equipment having excellent mechanical strength.

[0008]

According to a first aspect of the present invention, there is provided a tank for electric equipment which is formed by continuously bending a sheet-like thin steel plate to form a wavy projection and sealing both ends of the projection. In an electric equipment tank having a radiator plate and an upper side plate and a lower side plate joined inside the upper and lower ends of the corrugated radiator plate, at least one of the upper side plate and the lower side plate has a hollow cross section. It is characterized by providing reinforcement.

A tank for electric equipment according to a second aspect of the present invention is a corrugated radiator plate formed by continuously bending a sheet-like thin steel plate to form a corrugated protrusion, and sealing both ends of the protrusion. In an electric device tank having an upper side plate and a lower side plate joined to the upper and lower ends of the heat sink,
A reinforcing plate for bridging at least one of adjacent upper side plates or lower side plates is provided inside the tank.

According to a third aspect of the invention, there is provided a tank for electric equipment, wherein a sheet-like thin steel plate is continuously bent to form a wavy projecting portion, and both ends of the projecting portion are sealed. In an electric device tank having an upper side plate and a lower side plate joined to the upper and lower ends of the heat sink,
A reinforcing plate for bridging the upper side plate and the lower side plate is provided inside the tank.

In the electric equipment tank according to the fourth invention, at least one of the reinforcements having a hollow cross section is formed by bending an end of the upper side plate or the lower side plate.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. An embodiment of the present invention will be described with reference to FIGS. The same reference numerals as those in the related art denote the same or corresponding parts, and a description thereof will be omitted. In FIGS. 1 and 2, reference numeral 7 denotes an electric device main body. 8a is a reinforcing plate provided so as to bridge between the lower side plate 4 and the bottom plate portion 5. One end is fixed to the lower side plate 4 by welding, and the other end is fixed to the bottom plate portion 5 by welding. On the short side of the tank, a reinforcing plate 8b may be provided between the lower side plate 4 and the bottom plate portion 5 so that the cross section thereof forms a triangle. The reinforcing plate 8a
As shown in FIG. 3, contrary to FIG. 2, the long side of the tank may be constituted by one sheet, and the short side may be constituted by a plurality of reinforcing plates 8b.

Reference numeral 9 denotes a reinforcing plate provided so as to bridge between the upper side plate 3 and the flange portion 3a. One end is fixed to the upper side plate 3 by welding, and the other end is fixed to the flange 3a by welding. The cross section of the reinforcing plate 9, the upper side plate 3 and the flange 3a forms a hollow triangle. On the short side of the tank, a reinforcing plate may be provided between the upper side plate 3 and the flange portion 3a so that its cross section forms a triangle.

In the electric equipment tank having this configuration, when the enclosed cooling medium such as insulating oil or insulating gas expands due to heat generation of the electric equipment main body and fluctuations in the ambient temperature, the tank internal pressure increases. At this time, the upper side plate 3 and the lower side plate 4 receive a bending moment proportional to the square of the side length of the inner diameter of the tank, but the reinforcing plates 8 and 9 are separated at appropriate intervals in the horizontal direction, or
Since the single side plate is fixed to the lower side plate 4 and the bottom plate portion 5 by welding, the rigidity of the upper side plate 3 and the lower side plate 4 is increased, and the corrugated heat radiating plate 1, the upper side plate 3, and the lower side plate 4 near the center of the tank are provided.
, That is, the displacement and stress of the portion A1 in FIG. 1 can be kept below the allowable value. Since the stress of the plate material is proportional to the fourth power of the distance between the support points, it is more effective to appropriately select the mounting interval between the reinforcing plates 8 and 9 according to the generated force and the applied plate thickness.

As described above, in the electric equipment tank according to the present embodiment, at least one of the upper side plate 3 and the lower side plate 4 welded to the upper and lower ends of the corrugated radiator plate 1 has a hollow cross section. It is configured in a shape. Therefore, the mechanical strength of the portion where the repeated stress is generated due to the pressure fluctuation increases without increasing the thickness of the corrugated heat radiating plate 1, the upper side plate 3, and the lower side plate 4. For this reason, the rigidity of the upper side plate 3 and the lower side plate 4 increases, and even when internal and external pressures are applied, the upper side plate 3
Since the amount of displacement and the stress of the lower side plate 4 can be suppressed below the allowable values, the increase in material cost and product weight can be suppressed, the work of forming the corrugated heat sink 1 is easy, and the upper side plate 3 and the lower side plate 4 are corrugated. The reliability of the welded portion A1 with the heat sink 1 can be improved.

Further, since the reinforcing plate 8 is welded and fixed to the electric equipment main body 7 housed in the tank so that the flat portion thereof is opposed to the electric equipment main body 7, electric field concentration does not occur, and insulation between the electric equipment main body 7 and the electric equipment main body 7 is prevented. The distance can be reduced. Further, the cooling medium cooled by the corrugated heat radiating plate 1 is prevented from stagnating at the corners of the bottom plate portion 5, so that the cooling efficiency is improved and a small-sized electric device can be manufactured.

As shown in FIG. 4, the lower side plate 4 and the bottom plate 5 are bent so that the angle Θ between the lower side plate 4 and the bottom plate 5 becomes an obtuse angle. The parts may be individually welded.

Further, as shown in FIG.
The lower side plate 4 and the lower oblique reinforcing plate 8a may be formed of a single plate, and the reinforcing portions 8a and 8b may be bent from the bent portion 21 so that the cross section becomes triangular as shown in FIG. Since welding between the bottom plate 5 and the lower side plate 4 of the tank can be eliminated, the reliability against leakage of the cooling medium sealed in the tank can be improved. In addition, in the developed view shown in FIG. 5, a developed view in which both the long side and the short side of the tank are bent is shown, but only the long side or the short side may be bent.

Embodiment 2 One embodiment of the present invention will be described with reference to FIGS. 7 and 8, the same reference numerals as those in the related art denote the same or corresponding parts, and a description thereof will be omitted. One end of the corner reinforcing plate 10 facing the upper side plate 4 is welded to the upper side plate 3, and the other end similarly facing the lower lower side plate 4 is welded to the lower side plate 4. FIG.
, The adjacent upper side plate 3 and the corner reinforcing plate 10 form a hollow triangle, and the adjacent lower side plate 4 and the corner reinforcing plate 10 also form a hollow triangle.

In the electric equipment tank of this configuration, when the enclosed insulating medium such as insulating oil or gas expands due to heat generation of the electric equipment main body 7 and fluctuation of the ambient temperature, the internal pressure of the tank increases. At this time, the upper side plate 3 and the lower side plate 4 receive a bending moment proportional to the side length of the tank inner diameter. However, the corner reinforcing plate 10 is located between the upper side plate 3 and the lower side plate 4.
Since it is fixed by welding between them, it acts as a powerful column at the four corners of the tank. The corner reinforcing plate 10 is the upper side plate 3
And two sides are welded to each of the lower side plate 4 to form a hollow triangle, so that the rigidity of the upper side plate 3 and the lower side plate 4 increases, and when internal and external pressure is applied to the tank, the corrugated heat sink 1 near the corner and the upper part The displacement and stress at the root of the side plate 3 and the lower side plate 4 can be kept below the allowable values.

Further, since the corner reinforcing plate 10 for connecting the lower side plate 4 and the adjacent lower side plate 4 between the upper side plate 3 and the adjacent upper side plate 3 is provided in the tank, the upper side plate 3 is provided.
And the lower side plate 4 are fixed by the corner reinforcing plate 10 on the inner side, and the length of the straight portion L1 that is not fixed (hereinafter referred to as the length of the non-fixed straight portion) L1 is shortened, and the bending strength is improved. That is, the length of the non-fixed straight portion on one side of the tank when the reinforcing plate 10 is not provided is L2, but the length of the non-fixed straight portion can be reduced to L1 by providing the reinforcing plate 10, and the bending moment is equal to the length of the non-fixed straight portion. Since it is proportional to the square, it can be reduced to (L1 / L2) ² . Further, when the internal and external pressures act on the tank, the adjacent upper side plates 3 and the lower side plates 4 pull or push each other, so that a high strength electric device tank can be obtained.

As described above, the electric equipment tank according to the present embodiment has the corner reinforcing plates 10 welded to the four corners of the upper side plate 3 and the lower side plate 4. Therefore, according to the electric device tank, the mechanical strength of the portion where the repeated stress is generated due to the pressure fluctuation can be increased without increasing the thickness of the corrugated radiator plate 1, the upper side plate 3, and the lower side plate 4. For this reason, the rigidity of the corners of the upper side plate 3 and the lower side plate 4 is increased, and the displacement and stress of the upper side plate 3 and the lower side plate 4 can be suppressed to below an allowable value even when internal / external pressure acts on the tank. Increases in cost and product weight can be suppressed, the work of forming the corrugated radiator plate 1 is easy, and the reliability of the welded portion A1 between the upper side plate 3 and the lower side plate 4 and the corrugated radiator plate 1 can be increased.

Also, since the corner reinforcing plate 10 is welded and fixed to the electric equipment main body 7 accommodated in the tank so that the flat portion thereof is opposed to the electric equipment main body 7, electric field concentration does not occur, and the corner reinforcing plate 10 is connected to the electric equipment main body 7. The insulation distance can be reduced, and the size of the electric device can be reduced.

Even if the corner reinforcing plate 10 is provided, the coolant flow path of the wave-shaped heat radiating plate 1 flows smoothly by providing a gap corresponding to the thickness of the upper side plate 3 and the lower side plate 4, for example. Further, as shown in FIG. 8, the cooling efficiency of the corrugated heat radiating plate 1 is not impaired by drilling the holes 13 a and 13 b for the refrigerant flow passage in the upper and lower portions of the corner reinforcing plate 10.

Embodiment 3 One embodiment of the present invention will be described with reference to FIG. 9, the same reference numerals as those in the related art denote the same or corresponding parts, and a description thereof will be omitted. 11 is a lower corner reinforcing plate, and 12 is an upper corner reinforcing plate. The lower corner reinforcing plate 11 has one end thereof connected to the lower side plate 4.
The other end is welded to the adjacent lower side plate 4, and the upper corner reinforcing plate 12 is welded at one end to the upper side plate 3 and at the other end to the adjacent upper side plate 3. Upper side plate 3
And the upper corner reinforcing plate 12 to form a hollow triangle,
The lower side plate 4 and the lower corner reinforcing plate 11 also form a hollow triangle.

In the electric equipment tank of this configuration, when the enclosed insulating medium such as liquid or gas expands due to heat generation of the electric equipment main body 7 and fluctuation of the ambient temperature, the tank internal pressure increases.
At this time, the upper side plate 3 and the lower side plate 4 receive a bending moment proportional to the side length of the tank inner diameter. However, since the upper corner reinforcing plate 12 and the lower corner reinforcing plate 11 have two sides fixed to the upper side plate 3 and the lower side plate 4 by welding to form a hollow triangle, the upper side plate 3 and the lower side plate 4
When the internal and external pressures act on the tank, the displacement and stress of the corrugated radiator plate 1 near the corner and the roots of the upper side plate 3 and the lower side plate 4 can be kept below allowable values.

Further, since the upper and lower corner reinforcing plates 12 and 11 for connecting the adjacent upper side plates 3 and the adjacent lower side plates 4 are provided inside the tank, the upper side plate 3 and the lower side plate 4 are arranged inside. Upper and lower corner reinforcement plate 1
Since it is fixed by 2 and 11, the length of the non-fixed straight portion is reduced, and the bending strength is improved. When internal and external pressures act on the tank, adjacent upper side plates 3 and lower side plate 4
Since they mutually pull or push each other, a high strength electric device tank can be obtained.

As described above, the tank for electric equipment according to the present embodiment is obtained by welding the upper corner reinforcing plate 12 and the lower corner reinforcing plate 11 to the four corners of the upper side plate 3 and the lower side plate 4. Therefore, it is possible to increase the mechanical strength of the portion where the repeated stress is generated due to the pressure fluctuation without increasing the thickness of the corrugated heat radiating plate 1, the upper side plate 3, and the lower side plate 4. For this reason, the rigidity of the corners of the upper side plate 3 and the lower side plate 4 is increased, and the displacement and stress of the upper side plate 3 and the lower side plate 4 can be suppressed to the allowable values or less even when internal / external pressure is applied. An increase in product weight can be suppressed, the work of forming the corrugated radiator plate 1 can be easily performed, and the reliability of a welded portion between the upper side plate 3 and the lower side plate 4 and the corrugated radiator plate 1 can be increased.
Further, since the upper and lower corner reinforcing plates 12 and 11 are welded and fixed to the electric device main body 7 housed in the tank so that the flat portions thereof are opposed to each other, electric field concentration does not occur and the electric device main body 7 And the insulation distance between them can be reduced, and the size of the electrical equipment can be reduced.

By the way, in each of the above-described embodiments, the heat radiating tank in which the electric device main body is a transformer has been described.
Naturally, it can be used for electrical equipment other than transformers.

[0030]

As described above, according to the first aspect of the invention, the corrugated radiating plate is formed by continuously bending a sheet-like thin steel plate to form a corrugated protrusion and sealing both ends of the protrusion. And a tank for an electric appliance having an upper side plate and a lower side plate joined to the inside of the upper and lower ends of the corrugated heat radiating plate, wherein at least one of the upper side plate and the lower side plate has a hollow cross-sectional reinforcement. The bending strength of the upper side plate and the lower side plate is greatly increased, and the displacement and stress of the upper side plate and the lower side plate can be suppressed to below the allowable value even when internal and external pressures are applied to the tank. This has the effect of suppressing an increase in weight, facilitating the manufacture of the corrugated radiator plate, and increasing the reliability of the welded portion between the upper and lower side plates and the corrugated radiator plate.

According to the second aspect of the present invention, the sheet-like thin steel plate is continuously bent to form a wavy projecting portion, and both ends of the projecting portion are sealed. In the electric device tank having the upper side plate and the lower side plate joined to the inside of the end, since the reinforcing plate bridging at least one of the adjacent upper side plates or the lower side plate is provided inside the tank, The length of the non-fixed straight part of the side plate or the lower side plate is shortened and the bending strength is improved, and when internal and external pressure is applied to the tank, adjacent upper side plates or lower side plates are pulled or pressed together. Therefore, the strength of the tank for electric equipment with high strength is greatly improved, and the effect of preventing deformation and cracking of the lower side plate, the upper side plate, the corrugated heat sink, and the welded portion therebetween can be prevented. That.

According to the third aspect of the invention, the sheet-like thin steel plate is continuously bent to form a wavy projecting portion, and both ends of the projecting portion are sealed. In an electric equipment tank having an upper side plate and a lower side plate joined to the inside of the end, a reinforcing plate for bridging the upper side plate and the lower side plate is provided inside the tank, so that the reinforcing plate is provided between the upper side plates and the lower side plate. Since it is fixed by welding in between, it acts as a strong column at the four corners of the tank, and has the effect of further improving the strength of the tank.

According to the fourth aspect of the invention, in addition to the effects of the first aspect, the reinforcement having a hollow cross-section is formed by bending a bottom plate formed by bending at least one end to an upper side plate or a lower side plate. Since the welding with the lower side plate can be eliminated, there is an effect that the reliability against leakage of the cooling medium sealed in the tank can be improved.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a main part of an electric equipment tank according to an embodiment of the present invention.

FIG. 2 is a plan cross-sectional view (cross-section BB in FIG. 1) showing a main part inside the electric equipment tank according to the embodiment of the present invention.

3 is a plan cross-sectional view (cross-section BB in FIG. 1) showing a main part inside the electric equipment tank according to the embodiment of the present invention.

FIG. 4 is a side sectional view showing a main part of an electric equipment tank according to an embodiment of the present invention.

FIG. 5 is a development view showing a main part of the electric equipment tank according to the embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the bottom of the tank in the developed view of FIG. 5;

FIG. 7 is a plan view of the inside of the electric equipment tank according to the embodiment of the present invention.

FIG. 8 is a perspective view showing a main part inside an electric equipment tank according to an embodiment of the present invention.

FIG. 9 is a perspective view showing a main part inside an electric equipment tank according to an embodiment of the present invention.

FIG. 10 is a perspective view showing a main part of a conventional electric equipment tank.

FIG. 11 is a horizontal cross-sectional view showing a main part of a corrugated heat sink.

FIG. 12 is a vertical cross-sectional view illustrating a main part of a corrugated heat sink.

FIG. 13 is a perspective view showing a main part of the corrugated heat sink.

FIG. 14 is a side sectional view showing a main part of a conventional electric device tank.

FIG. 15 is a side sectional view of an essential part for explaining displacement of a conventional electric device tank due to internal pressure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Corrugated radiator plate, 2 Protruding portion of corrugated radiator plate, 3 Upper side plate, 4 Lower side plate, 5 Bottom plate, 6 Tank side plate, 7 Electric equipment body, 8 Lower side plate reinforcing plate, 9 Upper side plate reinforcing plate, 10 Corner reinforcement Plate, 11 Corner reinforcement plate of lower side plate, 12 Corner reinforcement plate of upper side plate, 13 Hole for refrigerant circulation.

Claims (4)

[Claims] 1. A corrugated heatsink formed by continuously bending a sheet-like thin steel plate to form a corrugated protrusion, and sealing both ends of the protrusion, and joining the corrugated heatsink to the inside of the upper and lower ends of the corrugated heatsink. An electric equipment tank having an upper side plate and a lower side plate, wherein at least one of the upper side plate and the lower side plate is provided with a reinforcement having a hollow cross section. tank. 2. A corrugated radiator plate formed by continuously bending a sheet-like thin steel plate to form a corrugated protrusion, and sealing both ends of the protruding portion, and joining the corrugated radiator plate inside the upper and lower ends of the corrugated radiator plate. An electric equipment tank having an upper side plate and a lower side plate, wherein a reinforcing plate for bridging at least one of the adjacent upper side plates or the lower side plate is provided inside the tank. tank. 3. A corrugated radiator plate formed by continuously bending a sheet-like thin steel plate to form a corrugated protrusion, and sealing both ends of the protruding portion, and joining the corrugated radiator plate inside the upper and lower ends of the corrugated radiator plate. An electric equipment tank having an upper side plate and a lower side plate, wherein a reinforcing plate for bridging the upper side plate and the lower side plate is provided inside the tank. 4. The electric equipment tank according to claim 1, wherein at least one of the reinforcements having a hollow cross section is formed by bending an end of an upper side plate or a lower side plate.