JPH08339919A - Wave case for electric equipment - Google Patents

Abstract

PURPOSE: To suppress the expansion of each crest part of a corrugated heat sink by locally performing the plastic deformation of the facing parts close to the tips of both side walls of the respective crest part of the corrugated heat sink, and forming the vertical groove parts extending along the ridge lines of the respective crest parts. CONSTITUTION: In a wave case 1, an upper frame 2 and a lower frame 3 are formed so that each cross section forms the shape, wherein roundness is formed at each corner part of a rectangle. A corrugated heat sink 4 is arranged in the striding pattern between the upper frame 2 and the lower frame 3 and welded and fixed to the upper frame 2 and the lower frame 3 at the upper end and the lower end of the plate. Then, the facing parts closer to the ends of both side walls 401 and 401' of each crest part 4a of the corrugated heat sink 4 locally undergo plastic deformation. Vertical grooves 402 and 402' extending in up-and-down direction along a ridge line 4a1 of each crest part 4a are formed on both sides of the tip part of each crest part 4a. Thus, the expansion of each crest part 4a of the corrugated heat sink 4 can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wave case for electric equipment using a corrugated heat dissipation plate on a side wall.

[0002]

2. Description of the Related Art As a case for electric equipment such as a transformer, a wave case 1 as shown in FIGS. 6 and 7 is used. The wave case includes an upper frame 2 and a lower frame 3, and a corrugated heat dissipation plate 4 that is disposed between the upper frame and the lower frame and has upper and lower ends welded to the upper frame and the lower frame, respectively. The lower end of the lower frame 3 is closed by a bottom plate 3a.
A flange 2a is provided on the upper end of the upper frame 2, and the lid plate 5 is attached to the flange 2a.

As shown in FIG. 8, the corrugated heat dissipation plate 4 has a ridge line direction (vertical direction of the case) of each crest part of a steel plate corrugated so that crests 4a and troughs 4b are alternately arranged. By closing both ends 4c of the above by welding, each mountain portion is formed into a bag shape and the cooling medium passage 4d is formed inside thereof. Each valley portion 4b of the corrugated heat dissipation plate 4 serves as an air passage, and heat is exchanged between the air flowing in the air passage and the cooling medium in the cooling medium passage 4d. An electric device body 6 such as a transformer is accommodated in the wave case 1 together with an insulating medium such as insulating oil or insulating gas.

[0004]

The corrugated heat dissipation plate used in the corrugated case as described above is manufactured by corrugating a thin steel plate with a corrugating forming machine. In this case, it was unavoidable that the crests had a shape bulging outward due to the buckling caused by the springback of the steel plate, and the thickness of the crests became larger than the prescribed thickness.

Further, as described above, when the peaks of the corrugated heat dissipation plate have a shape that bulges outward, the peaks tend to swell when the internal pressure of the case rises. In the hermetically sealed electric device, when the cooling medium expands due to the heat generated from the electric device during operation and the internal pressure of the case rises, each mountain portion 4a of the corrugated heat dissipation plate 4 greatly expands as shown in FIG. There is a problem that the valleys (air passages) 4b, 4b, ... Formed between the series of peaks 4a, 4a ,.

Therefore, as shown in FIG. 10, the ridgeline 4 of the ridge portion 4 is formed near the center of both side walls of each ridge portion 4a of the corrugated heat dissipation plate 4.
A plurality of vertical grooves g extending along the lengthwise direction of a1 are formed by press working to reinforce (Actual exploitation 56-61).
No. 029) was proposed, but even if such reinforcement is performed, it is not possible to correct the shape bulging to the outside of each mountain portion of the heat dissipation plate, so as shown in FIG. It was unavoidable that the bulge of the mountain portion 4a became large.

An object of the present invention is to provide a wave case for electric equipment which can suppress expansion of each mountain portion of the corrugated heat dissipation plate.

[0008]

According to the present invention, the inside of each crest is closed by welding both ends in the ridge direction of each crest of a steel plate corrugated so that crests and troughs are alternately arranged. The present invention relates to a wave case for electric equipment having a hermetically sealed structure in which a corrugated heat dissipation plate having a cooling medium passage is attached to a side wall.

According to the present invention, the opposite portions of both side walls of each crest portion of the corrugated heat dissipation plate near the tip (top) are locally plastically deformed, and the crest portions are provided on both sides of the tip portion of each crest portion. The vertical groove portion extending along the ridgeline of was formed.

In the present invention, the portions located between the hem portions of both side walls of each peak portion of the corrugated heat dissipation plate and the vertical groove portion are locally plastically deformed so as to be substantially perpendicular to the vertical groove portion. It is preferable to form a plurality of extending lateral groove portions at intervals in the ridgeline direction of each mountain portion.

[0011]

As described above, when the tip of each peak of the corrugated heat sink is plastically deformed to form vertical grooves on both sides of each peak, compared to the case where reinforcement is provided near the center of each peak. It was confirmed that the amount of swelling in each mountain area decreased.

Further, when the vertical groove portion is formed at the tip of each mountain portion and a plurality of lateral groove portions are formed between the hem portion of each mountain portion and the vertical groove portion, expansion of each mountain portion can be further suppressed. Became clear.

[0013]

1 and 2 show an embodiment of the present invention. A wave case 1 of this embodiment has a rectangular cross section having a rounded corner (corner). The upper frame 2 and the lower frame 3 formed in the upper frame 2 and the upper frame 2 and the lower frame 3 that are arranged between the upper frame 2 and the lower frame 3 and have upper and lower ends respectively.
And a corrugated heat dissipation plate 4 welded to the lower frame 3. As shown in FIG. 2 (A), the corrugated heat dissipation plate 4 has a ridge direction (vertical direction) of each crest portion 4a of a steel plate corrugated so that crest portions 4a and trough portions 4b are alternately arranged. Both ends 4c,
Each crest is formed into a bag shape by closing 4c by welding, and a cooling medium passage 4d is formed inside each crest 4a.

The lower end of the lower frame 3 is hermetically and liquid-tightly closed by a bottom plate 3a welded to the lower frame. An outer flange 2a is provided on the upper end of the upper frame 2, and a lid plate 5 that closes the upper end opening of the case 1 is attached to the flange 2a.

In the present invention, as shown in FIG. 2 (A), both side walls 401, 401 'of each peak of the corrugated heat dissipation plate 4 are formed.
The opposite parts near the tip of the are locally plastically deformed,
Vertical groove portions 402, 402 'extending in the up-down direction are formed on both sides of the tip of each mountain portion along the ridgeline 4a1 of the mountain portion.

In the conventional corrugated case, since the peaks of the corrugated heat dissipation plate have a shape that bulges outward due to the back ring generated during molding, the peaks tend to bulge when the internal pressure rises. Further, in the conventional wave case, since the tip portions of the peak portions of the corrugated heat dissipation plate are not reinforced, the tip portions of the peak portions are easily deformed. Therefore, in the conventional corrugated case, when the internal pressure of the case rises, each crest easily swells, and both side walls 401, 4 of each crest.
When 01 ′ is displaced outward, the tip end portions of the respective mountain portions are easily deformed, and the displacement of both end portions 4c, 4c in the ridge direction in the direction of approaching each other is easily allowed. Therefore, when both side walls of each crest portion 4b bulge outward when the internal pressure rises, both side walls 4c, 4c in the ridge direction of each crest portion are pulled by the bulge of both side walls.
Are displaced toward each other, and this displacement promotes the bulging of the side wall of the mountain portion 4b.
It was unavoidable that the bulge of each mountain part became large as shown in.

On the other hand, as in the present invention, the corrugated heat dissipation plate 4 is used.
By plastically deforming the parts near the tips of both side walls of each mountain part of
When the vertical groove portions 402 and 402 'are formed at the tip of each mountain portion, the bulging due to the buckling that occurs during the molding of each mountain portion is corrected, so that the shape of each mountain portion can be made difficult to bulge. . Further, when the vertical groove portion is formed by plastically deforming the portion of each crest near the tip, the strength of the crest near the tip is improved, and the tip of each crest is less likely to deform. Since the tip of each crest becomes particularly strong against the compressive force acting in the vertical direction, the side wall of each crest is displaced outward when the internal pressure of the case rises, and the ridge line of each crest accordingly. When both end portions 4c, 4c in the direction try to displace in a direction in which they approach each other, the tip portions of the respective mountain portions prevent the displacement. As a result, the deformation of each crest is suppressed, so that the bulge of each crest when the internal pressure of the case rises can be reduced.

In an actual oil-filled transformer, a comparison was made between the case where a vertical groove is formed at the tip of each peak of the corrugated heat dissipation plate and the case where no vertical groove is formed. It was confirmed that when the vertical groove portion was formed in the portion, the bulge of each mountain portion was smaller than that in the conventional case as shown by the chain line in FIG. 2 (B).

FIG. 5 shows that the internal pressure of the wave case is varied between the case A in which a vertical groove is formed at the center of each peak of the corrugated heat sink and the case B in which a vertical groove is formed at the tip of each peak. It shows the result of measuring the change in the thickness T of the peak portion of the corrugated heat sink in the case of. In the figure, To indicates the thickness of the crest portion when the internal pressure does not rise. From this result, as in the present invention, when the vertical groove portion extending along the ridgeline of each ridge portion is formed by plastically deforming the tip end portion of each ridge portion of the corrugated heat sink, the vertical portion is formed in the center portion of each ridge portion. It can be seen that the bulge of the peak portion when the internal pressure rises is smaller than that in the case where the groove portion is formed.

3 and 4 show another embodiment of the present invention. In this embodiment, each peak portion 4a of the corrugated heat dissipation plate 4 is shown.
Vertical groove portions 402 and 402 'are formed on both sides of the tip end portion of each of the ridges, and the hem portions 401a and 401a' of both side walls 401 and 401 'of each mountain portion 4a and the vertical groove portions 402 and 402' are formed.
The opposite portions of the region located between and are locally plastically deformed, and four lateral groove portions 403A to 403D and 403A extending in a direction substantially perpendicular to the vertical groove portions 402 and 402 '.
'To 403D' (403A ', 403B' and 403D
´ is not shown. ) Are formed in parallel with each other at intervals in the direction (vertical direction) of the ridgeline 4a1 of each mountain portion.

In the embodiment shown in FIGS. 3 and 4, four lateral groove portions 403A to 403D and 403A 'to 403D provided on both side walls 401 and 401' of each mountain portion, respectively.
′, Two lateral groove portions 403B, 403C and 403B ′ provided near the central portion in the ridge direction of each mountain portion,
The length of 403C 'is set longer than the lengths of the other lateral groove portions 403A, 403D and 403A', 403D '.

As shown in FIGS. 3 and 4, the vertical groove portion 40
By providing lateral groove portions 403A to 403D and 403A 'to 403D' in addition to 2,402 ', the strength of each mountain portion can be further increased, and therefore the bulge of each mountain portion when the internal pressure rises is further reduced. You can

In the embodiment shown in FIGS. 3 and 4, four lateral groove portions are provided on both side walls of the corrugated heat dissipation plate 4, but the number of the lateral groove portions is arbitrary.

[0024]

As described above, according to the present invention, the vertical groove is formed by plastically deforming both sides of the tip of each crest of the corrugated heat dissipation plate, and the shape of each crest is less likely to swell. In addition to the above, the strength near the tip end of each crest was increased to prevent displacement of both ends in the ridge direction of the crest toward each other when the internal pressure of the case increased.
There is an advantage that the bulge of each crest portion when the internal pressure rises can be made smaller than in the conventional case, and the cooling efficiency is prevented from being lowered by narrowing the air passage between the crest portions of the corrugated heat dissipation plate.

[Brief description of drawings]

FIG. 1 is a side view showing a partial cross section of an essential part of an embodiment of the present invention.

FIG. 2A is a sectional view taken along line AA of FIG. (B)
FIG. 3 is a cross-sectional view for explaining the deformation of the mountain portion of the heat dissipation plate that occurs when the internal pressure of the case rises in the embodiment of FIG. 1.

FIG. 3 is a side view showing a partial cross-section of a main part of another embodiment of the present invention.

4 is a sectional view taken along line BB of FIG.

FIG. 5 is a diagram showing the relationship between the case internal pressure and the bulge of the peak portion of the corrugated heat dissipation plate for the corrugated case according to the present invention and the conventional corrugated case.

FIG. 6 is a vertical cross-sectional view showing an example of an electric device with a wave case.

FIG. 7 is a cross-sectional view of the electric device shown in FIG.

FIG. 8 is a top view showing the structure of a corrugated heat dissipation plate used in a conventional wave case.

FIG. 9 is a cross-sectional view showing a bulge generated in a mountain portion of a heat dissipation plate used in a conventional wave case.

FIG. 10 is a side view showing another heat dissipation plate used in the conventional wave case.

FIG. 11 is a cross-sectional view showing a bulge generated in each mountain portion of the heat dissipation plate of FIG.

[Explanation of symbols]

 1 wave case 2 upper frame 3 lower frame 3a bottom plate 4 corrugated heat dissipation plate 4a mountain part 4a1 mountain ridge line 4b valley part 401, 401 'mountain part side walls 402, 402' vertical groove parts 403A to 403D, 403A 'to 403D' Lateral groove 5 Lid plate

Claims (2)

[Claims] 1. A waveform in which a cooling medium passage is formed inside each ridge by welding both ends in the ridge direction of each ridge of a steel plate corrugated so that the ridges and valleys are alternately arranged. In a wave case for electric equipment of a sealed structure in which a heat sink is attached to a side wall portion, opposite portions of both side walls of each crest portion of the corrugated heat sink plate that face each other are plastically deformed locally, and the tip of each crest portion is locally deformed. A wave case for an electric device, characterized in that vertical groove portions extending along the ridgeline of the mountain portion are formed on both sides of the portion. 2. A plurality of portions, which are located between the hem portions of both side walls of each peak portion of the corrugated heat dissipation plate and the vertical groove portion, are locally plastically deformed to extend in a direction substantially perpendicular to the vertical groove portion. The wave case for an electric device according to claim 1, wherein the lateral groove portions are formed at intervals in the ridge direction of each mountain portion.