EP0391325B1

EP0391325B1 - Container for accomodating electrical apparatus

Info

Publication number: EP0391325B1
Application number: EP19900106325
Authority: EP
Inventors: Akio C/O Mitsubishi Denki K.K. Kishi; Katsuaki C/O Mitsubishi Denki K.K. Itoh; Kazuo C/O Mitsubishi Denki K.K. Yoshida; Toyokazu C/O Mitsubishi Denki K.K. Kouan; Taihei C/O Mitsubishi Denki K.K. Adachi; Yasushi C/O Mitsubishi Denki K.K. Fuwa
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1989-04-05
Filing date: 1990-04-03
Publication date: 1994-01-19
Anticipated expiration: 2010-04-03
Also published as: EP0391325A1; DE69006073T2; DE69006073D1

Description

BACKGROUND OF THE INVENTION

This invention concerns a container for a plurality of electrical instruments such as a transformer and a voltage regulator.
Fig. 1 is a schematic drawing showing a conventional container for a transformer and a voltage regulator.
In the figure, a container 1 has a partition which divides the container 1 into two areas 3 and 4. Partition 2 comprises a mounting portion 21 fixed to the container 1 and a disk-shaped, electrically-insulating partition plate 22 which is fixed to this mounting portion 21. A plurality of terminals 5 are attached to the partition place as shown in Fig. 2, and each terminal passes through the plate to form a coupling portion for lead wires. A transformer 6 is located in one area 3 of the container, a group 7 of tap leads drawn up from tap coils is mounted on the transformer, and tap leads 8 extending from the the group of tap leads connected to tap coils are connected to terminals 5 on one surface of the partition plate 22. A voltage regulator 9 is installed in the other area 4 of the container, and tap leads 10 connect the terminals of the voltage regulator to the terminals 5 on the other surface of the partition plate 22.
A similar container with the features of the preamble of claim 1 has become known from FR-A-1 382 245.
Conventional containers for electrical instruments have the construction described above. As the number of the tap leads is increased, a partition plate with a larger surface area is required. As a result, the dimension of the container must be enlarged which gives rise to manufactering difficulties and restrictions on means of transportation. Further, in the event of a breakdown of the instruments lodged in the container or when evacuating the container to fill it with insulating oil, after inspecting the voltage regulator 9, the partition plate 22 occasionally was subject to high pressure. If the plate had a large surface area, its thickness had to be increased so that it could fully withstand these pressures.

SUMMARY OF THE INVENTION

This invention was conceived to overcome the above problems. It aims to furnish a container wherein a large number of terminals can be provided without increasing the size of the whole container, which has a partition with sufficient strength to fully withstand external pressures.
The electrical instrument container of this invention comprises the features of claim 1.
According to this invention, as more terminals are required on the cylindrical member of the partition, the surface area of the partition to which terminals are attached can be enlarged by increasing the length of the cylinder in the axial direction. Further, the cylindrical wall of the cylindrical member can fully withstand external pressures of the type mentioned above.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a schematic diagram showing a conventional container for a transformer and a voltage regulator.
Fig. 2 is a schematic diagram showing a partition plate used in the conventional container.
Fig. 3 is a perspective drawing showing a container of Embodiment 1 of this invention.
Fig. 4 is an enlarged perspective view of a cylindrical member of Embodiment 1.
Fig. 5 is a schematic cross-sectional diagram showing Embodiment 1 of this invention.
Fig. 6 is a partially cross-sectional front view showing a cylindrical member of the above embodiment.
Fig. 7 is a partially cross-sectional front view showing a cylindrical member of Embodiment 2 of this invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiment

1

An embodiment of this invention will be described with reference to Figs. 3 to 6. As illustrated, the container of this embodiment has a first tank 103 for accommodating a transformer 6 with a group 7 of tap leads connected to tap coils, a second tank 104 for accommodating a voltage regulator 9, and a connecting portion 20 for connecting the first tank 103 and the second tank 104. Tanks 103 and 104, and connecting portion 20 are filled with electrically insulating oil for the purpose of electrically insulating and cooling the apparatus. Instead of insulating oil, other fluid such as SF₆ (Sulfur hexafluoride) gas may be used. The first tank 103 and second tank 104 are both of a rectangular parallelepiped. The connecting portion 20 is in the form of a tube with a rectangular cross section, and the both ends are attached to the upper parts of the lateral faces of tanks 103 and 104, with the space inside the connecting portion communicating with the space in each tank. Tank 103, connecting portion 20, and tank 104 are arranged in such a manner that respective upper surfaces are in the same plane.
The cross section of the connecting portion 20 is generally smaller than the vertical sections of the tanks 103 and 104. The connecting portion 20 is provided with a mounting portion 21 having a disk-shaped opening 21a. The mounting portion 21 is attached at its four sides to the inner surfaces of four walls of the connecting portion 20, being so disposed that its flat surface is orthogonal to the direction in which the connecting portion 21 extends. A cylindrical member 30 formed of an electrically insulating material is fixed to the mounting portion 21. Specifically, the cylindrical member 30 comprises a cylindrical wall 23, an end plate 24 continuous with and integrally formed with the cylindrical wall 23 for closing one end of the cylinder formed by cylindrical wall 23, and a flange portion 25 connected to the other end of the cylindrical wall and integrally formed with the cylindrical wall. Flange portion 25 is annular and is fixed to the mounting portion 21. The cylindrical member 30 and the mounting portion 21 together form a partition 102 which sealingly isolates the two areas. The inner diameter of the flange coincides with the outer diameter of the cylindrical wall 23, and the outer diameter is larger than the opening 21a of the mounting portion 21 so that the flange overlaps with the mounting portion 21. The axis of the cylindrical wall 23 extends in the longitudinal direction of the connecting portion 20, i.e., in the direction in which the connecting portion 20 extends.
In the illustrated embodiment, the mounting portion 21 is disposed nearer to the tank 104 and the cylindrical member 30 extends from this mounting portion 21 toward the other tank 103. A plurality of terminals are provided on the cylindrical wall 23 of the cylindrical member 30, passing through the wall 23. Lugs 51 are attached to the terminals 5 on a first or outer surface and lugs 52 are attached to the terminals on a second or inner surface of the wall 23. Tap leads 8 from the group 7 of tap leads drawn up from tap coils of the transformer 6 are connected to lugs 51 on the outer surface of the cylindrical wall 23, while tap leads 10 from the voltage regulator 9 are connected to lugs 52 on the inner surface of the cylindrical wall 23.
In this embodiment, terminals 5 are arranged in three rows spaced from each other in the axial direction of cylindrical member 30. The terminals in the respective rows are spaced at suitable intervals over the entire circumference of the cylindrical wall 23. The number of rows in the axial direction and the number of terminals in each row may be determined according to the total number of terminals.
Instead of providing a single cylindrical member 30 as illustrated, a plurality of cylindrical members 30 may be provided. In this case, the mounting portion 21 should have a plurality of openings corresponding to the number of the cylindrical members. By providing a plurality of cylindrical members, an even greater number of terminals can be provided.
In the above embodiment, cylindrical member 30 projects toward the area in which the transformer is installed, but the same effects are obtained even if it projects toward the area in which the voltage regulator is installed.
By using a cylindrical wall as a part of the cylindrical member of said partition 102, its surface area can be made larger, and a greater number of terminals can be provided on it. Further, by employing a cylindrical wall, mechanical strength is improved, and the cylindrical structure is capable of withstanding external forces even if the partition plate is made thin.
Further, the same effects will be obtained if other electrical instruments, such as a tap changer, a capacitor or a reactor is installed in the container instead of the transformer or the voltage regulator.

Embodiment 2

Fig. 5 shows another embodiment of this invention wherein terminals 7 are also provided on the end plate 24 of the cylindrical member 30. The other elements of the apparatus are similar to those of Embodiment 1 and the description thereof will therefore be omitted.
By adopting this design, an even greater number of terminals can be provided on the partition. In addition, if terminals are provided on the end plate 24, the distance to these terminals from the wall of connecting portion 20 which is at ground potential is greater than that to the terminals on the cylindrical wall 23, and electrical insulation is thereby increased.
Tap leads 8 and 10 at high potential may therefore be connected to terminals 5 on end plate 24, while those at low potential may be connected to terminals 5 on the cylindrical wall 23 of cylindrical member 30. The insulation can thus be increased.

Claims

A container for accommodating electrical apparatus, comprising:
a first tank (103) for lodging electrical apparatus;
a second tank (104) for lodging electrical apparatus;
a connecting portion (20) for connecting said first tank and said second tank;
a partition (21, 30) disposed in the connecting portion; and
a plurality of terminals (5) provided on said partition through which electrical apparatus in respective tanks are electrically connected with each other;
characterized in that said partition comprises a cylindrical member (30) closed at one end and having a flange portion (25) at the other end, and mounting portion (21) for fixing said cylindrical member to said container through said flange portion, said terminals being provided on said cylindrical member.
A container for electrical apparatus according to claim 1, wherein said cylindrical member (30) is a hollow right circular cylinder.
A container for electrical apparatus according to claim 1, wherein said cylindrical member extends in the direction in which said connecting prtion extends.
A container for electrical apparatus according to claim 1, wherein said cylindrical member comprises a cylindrical wall (23) and an end plate (24) continuous with one end of said cylindrical wall, and said flange portion (25) is continuous with the other end of said cylindrical wall.
A container for electrical apparatus according to claim 4, wherein said terminals are provided through said cylindrical wall of said cylindrical member.
A container for electrical apparatus according to claim 5, wherein said terminals are also provided through said end plate of said cylindrical member.
A container for electrical apparatus according to claim 6, wherein tap leads (8, 10) at relatively high potential are connected to terminals on said end plate, while those (8, 10) relatively at low potential are connected to terminals on said cylindrical wall of said cylindrical member.