JP2005129347A - High pressure switch and cabinet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure switch capable of making use of inherent merits of the small size and the low cost of an insulating resin box, serving as a pressure relief that allows the setting of pressure at which pressure relief operation starts at a lower value, and relieves quickly internal pressure to the outside to prevent damaged parts from flying to the outside, and to provide a cabinet in which such a high pressure switch is housed. <P>SOLUTION: The high pressure switch is configured to fix the opening of an insulating resin box by retaining hardware 31 with the opening being covered by a rubber packing 32. Consequently, if the internal pressure is increased, the rubber packing 32 is inflated, and finally separated from the retaining hardware 31. As a result, even if pressure at which pressure relief operation starts is made lower, pressure relief can be performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-pressure switch having a pressure relief structure against an internal short-circuit accident, and a cabinet that houses these high-pressure switches.

  A high voltage switch is a device that opens and closes an electric circuit between a high voltage bus and a customer side distribution line cable. There are various types of pressure release structures for prior art switches. For example, as in the invention described in Patent Document 1 (title of the invention: pressure release device for a switch), a lid that covers the opening of the switch body is provided. Using the bending of the lid, local weakness, or sliding of the locking part to quickly release the internal pressure to the outside and prevent the occurrence of a situation where damaged parts inside the switch body are scattered outside It has been known.

  The present applicant has invented a switch in which a fixed electrode and a movable electrode are housed in an independent space formed of an insulating material and has filed a patent application. This application has already been published and is disclosed as Patent Document 2. In this switch, that is, a fixed electrode formed by a pair of finger contacts and a movable electrode formed by a single blade contact are formed by an insulating resin box made of epoxy resin and an insulating plate (lid). It is housed in an independent space to reduce ground faults and short circuit accidents, and to reduce size and cost.

Japanese Patent Laid-Open No. 10-21800 (paragraph numbers 0012 to 0014, FIGS. 1 and 2) JP 2003-68173 A (paragraph numbers 0010 to 0022, FIGS. 1 to 4)

  However, in recent years, there has been a demand for downsizing of the high voltage switch, and the insulating resin box itself has also been downsized. Therefore, the insulation resin box is thickened or a reinforcing rim is provided to obtain sufficient mechanical strength. However, in a structure in which an independent space is formed by the insulating plate and the insulating resin box, there is a demand for setting the pressure release operation start pressure to a low value in order to cope with an effective pressure release operation. For example, in the pressure release mechanism of Patent Document 1, it is difficult to set the pressure release operation start pressure to a low value, and in order to lower the pressure release operation start pressure, it is necessary to provide a special pressure release mechanism in the insulating resin box. is there. However, providing a pressure relief mechanism that mechanically becomes a local weak point while maintaining mechanical strength has a problem that it becomes a more complicated shape than necessary and causes an increase in cost.

  Accordingly, the present invention has been made to solve the above-described problems, and its purpose is to set the pressure release operation start pressure to a low value, and quickly release the internal pressure to the outside so that the damaged parts are scattered externally. To provide a high-pressure switch that can make the most of the original advantages of downsizing and cost reduction of an insulating resin box, and a cabinet that houses such a high-pressure switch .

The high voltage switch according to claim 1 of the present invention is
High-voltage switching that opens and closes the electric circuit between the high-voltage bus and the customer-side distribution line cable by storing the fixed electrode and the movable electrode in closed closed spaces made of insulating material, and moving the movable electrode to and from the fixed electrode. In the vessel
An insulating resin box having an insulating resin box opening;
First and second fastening portions provided in the vicinity of the insulating resin box opening;
A flat elastic body fastened by the first fastening portion;
A holding fitting that has a holding fitting opening and is fastened by the first and second fastening portions in the vicinity of the holding fitting opening;
With
With the peripheral edge surface of the insulating resin box opening and the peripheral edge surface of the presser metal opening sandwiching the peripheral part of the flat elastic body, the presser metal and the flat elastic body are fastened by the first fastening portion, and the second fastening is performed. Only the holding metal fitting is fastened by the portion, the flat elastic body seals the insulating resin box opening, and when the internal pressure rises, the second fastening portion side of the flat elastic body separates and releases the pressure.

Moreover, the high voltage switch according to claim 2 of the present invention is:
The high voltage switch according to claim 1,
The first and second fastening portions are constituted by male and female screws provided in the vicinity of the insulating resin box opening,
The flat elastic body has an insertion hole only on one side thereof,
The presser bracket has a plurality of insertion holes around the presser bracket opening,
In a state where the opening peripheral edge of the insulating resin box and the opening peripheral edge of the presser bracket sandwich the flat elastic body, the male screw passing through the insertion hole of the presser metal fitting and the flat elastic body, and The male screw that passes only through the insertion hole of the presser fitting is fastened to the female screw, and the flat elastic body seals the opening of the insulating resin box. When the internal pressure rises, the side without the insertion hole of the flat elastic body is released and released. It is characterized by pressing.

A high voltage switch according to claim 3 of the present invention is
In the high voltage switch according to claim 1 or 2,
The fixed electrode and the movable electrode are respectively housed in a plurality of closed independent spaces formed by being separated from each other by an insulating material, and the movable electrode moves in a direction perpendicular to the parallel arrangement direction of the plurality of independent spaces. And

Moreover, the high voltage switch according to claim 4 of the present invention is:
In the high voltage switch according to any one of claims 1 to 3,
A movable-side external connection terminal electrically connected to the movable electrode via the movable-side embedded conductor;
A fixed-side external connection terminal electrically connected to the fixed electrode via the fixed-side embedded conductor;
Is embedded in a resin insulation box and is integrally arranged.

Moreover, the high voltage switch according to claim 5 of the present invention is:
In the high voltage switch according to any one of claims 1 to 4,
The fixed electrode is formed by a pair of finger contacts, and the movable electrode is formed by a single blade contact.

A high voltage switch according to claim 6 of the present invention is
In the high voltage switch according to any one of claims 1 to 5,
The insulating resin box is formed of an epoxy resin, and the flat elastic body is formed of an insulating EPT rubber.

A cabinet according to claim 7 of the present invention is
A plurality of the high-voltage switches according to any one of claims 1 to 6 are accommodated.

  According to the present invention as described above, the pressure release operation start pressure can be set to a low value, and the insulating resin box has as a pressure release part that quickly releases the internal pressure to the outside and prevents external damage of the damaged parts. It is possible to provide a high voltage switch that can make the most of the original merits of downsizing and cost reduction, and a cabinet in which such a high voltage switch is housed.

The best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a high-pressure switch according to this embodiment, FIG. 1 (a) is a front view, FIG. 1 (b) is a cross-sectional view taken along line AA, and FIG. FIG.
As shown in FIGS. 1A and 1B, the high-voltage switch 100 includes an insulating resin box 10, an insulating link 11, a movable electrode 12, a support shaft 13, a movable side embedded conductor 14, and a movable side external connection terminal 15. The arc extinguishing cylinder 16, the fixed electrode 17, the fixed-side embedded conductor 18, the fixed-side external connection terminal 19, the back cover 20, and the pressure release part 30 are provided.

The insulating resin box 10 is a substantially rectangular parallelepiped box formed of insulating resin. As this insulating resin, for example, an epoxy resin that is excellent in mechanical strength, electrical insulation resistance, and chemical resistance and can be easily molded into various shapes is desirable. The insulating resin box 10 has an opening formed on one side surface and is sealed with a back cover 20 after assembling an internal mechanism to be described later. In addition, an independent space is formed for three phases by a partition wall (not shown) on the other side, and three substantially rectangular insulating resin box openings are formed on the side surface. In FIG. 1 (a), only the left insulating resin box opening 10a is shown. In the vicinity of the four corners of the insulating resin box opening 10a, screw hole fittings are respectively buried, and four screw holes 10b are formed.
Such an insulating resin box opening 10a is sealed by a pressure release part 30 (details will be described later) that also serves as a lid.

The insulating link 11 is connected to an operation mechanism (not shown) via a drive shaft 11a, and is a link body that rotates about the drive shaft 11a as a central axis. The insulating link 11 is provided in each of the three-phase independent spaces.
The movable electrode 12 is a substantially F-shaped blade contact as viewed from the side, and the base end portion of the movable electrode 12 is pivotally supported by the support shaft 13 and is further rotated with the insulating link 11. It is connected and rotated by a driving force conducted from the insulating link 11. The movable electrode 12 is provided in each of the three-phase independent spaces. The movable electrode 12 moves in a direction orthogonal to the parallel arrangement direction of these independent spaces (the axial direction of the drive shaft 11a) (in other words, it can be said that the parallel electrode rotates around the parallel arrangement direction).

The movable embedded conductor 14 is electrically connected to the movable electrode 12 and is embedded in the insulating resin box 10.
The movable side external connection terminal 15 is electrically connected to the movable side embedded conductor 14 and is provided so as to protrude from the insulating resin box 10. In this embodiment, the movable-side embedded conductor 14 and the movable-side external connection terminal 15 are integrally formed and further provided for three phases. A three-phase high-voltage bus (not shown) is connected to the three-phase movable-side external connection terminals 15.

The arc-extinguishing cylinder 16 is formed in a substantially square shape by, for example, Duracon.
The fixed electrode 17 is a pair of finger contacts, and is disposed on the inner end of the arc extinguishing cylinder 16 on the rotation path of the movable electrode 12.
The arc extinguishing cylinder 16 and the fixed electrode 17 are provided in each of the three-phase independent spaces.

The fixed embedded conductor 18 is electrically connected to the fixed electrode 17 and is embedded in the insulating resin box 10.
The fixed-side external connection terminal 19 is electrically connected to the fixed-side embedded conductor 18 and is provided so as to protrude from the insulating resin box 10. In the present embodiment, the fixed-side embedded conductor 18 and the fixed-side external connection terminal 19 are integrally formed and further provided for three phases. These three-phase fixed-side external connection terminals 19 are connected to a three-phase consumer-side distribution line cable (not shown).

  The movable side external connection terminal 15, the movable side embedded conductor 14, the fixed side embedded conductor 18, and the fixed side external connection terminal 19 are integrally held and fixed by the insulating resin box 10. Further, one of the openings on the side surface of the insulating resin box 10 is sealed by the back cover 20 and the other is sealed by the pressure release part 30, whereby the independent space of each phase is a closed space.

  Next, the operation of such an internal mechanism will be described. The movable electrode 12 moves by rotating around the drive shaft 13, and the blade contact of the movable electrode 12 is sandwiched between the pair of finger contacts of the fixed electrode 17 and is electrically connected. The arc extinguishing cylinder 16 generates gas by touching an arc generated when the movable electrode 12 and the fixed electrode 17 are connected to promote arc extinguishing.

Next, the pressure relief unit 30 will be described.
The pressure relief unit 30 includes a presser fitting 31, a rubber packing 32, and a screw 33.
The holding metal fitting 31 is a metal fitting formed by bending a metal plate into a substantially U-shaped cross section and further processing and forming a holding metal opening 31a and an insertion hole 31b.
The rubber packing 32 is an example of the flat elastic body of the present invention. For example, an elastic material such as insulating EPT rubber, which is excellent in insulation and weather resistance, and is low in cost, is formed into a rectangular flat plate. The two insertion holes 32a are formed on one side (the upper short side in FIG. 1).

In such a pressure release part 30, the insulating box opening 10 a, the rubber packing 32, and the presser fitting 31 are arranged so as to overlap each other, and on the upper side, screws are inserted into the insertion holes 31 b of the presser fitting 31 and the insertion holes 32 a of the rubber packing 32. 33, and on the lower side, the screw 33 is inserted only into the insertion hole 31b of the presser fitting 31, and finally the four screws 33 are fastened.
The upper fastening portion corresponds to the first fastening portion of the present invention, and the lower fastening portion corresponds to the second fastening portion of the present invention.

  In the pressure release part 30, the peripheral part of the rubber packing 32 is fixed between the peripheral end face of the insulating resin box opening 10 a of the insulating resin box 10 and the peripheral end face of the pressing metal opening 31 a of the presser fitting 31. Is done. The rubber packing 32 closes the insulating resin box opening 10 a to form an independent space (closed space) closed in the insulating resin box 10.

Next, the pressure release by the pressure release unit 30 will be described.
Normally, as shown in FIG. 2A, the peripheral edge of the rubber packing 32 is pressed by the peripheral end face of the pressing metal opening 31a of the pressing metal 31, and the internal gas does not leak to the outside.
However, when an internal short circuit occurs in the high-voltage switch 100, the rubber packing 32 swells as shown in FIG. As shown in FIG. 2 (c), the clamping side (in other words, the lower side of the peripheral end face of the insulating resin box opening 10 and the lower side of the peripheral end face of the pressing metal opening 31a of the pressing metal 31 (in other words, The rubber packing 32 on the second fastening part side or the side where there is no insertion hole and is not screwed) is slid and opened to release the pressure quickly.

  Since the pressure release part 30 is in such a pressure release form, it is possible to set the pressure release operation start pressure to a low value, and immediately release the internal pressure to the outside immediately after the occurrence of an internal short circuit, thereby preventing external scattering of damaged parts. . As a result, the insulating resin box has an advantage that it is not necessary to thicken the resin or provide a reinforcing rim so that it can withstand an excessive pressure release operation start pressure. In addition, it is possible to adjust the pressure at which the pressure is released by adjusting the fastening force of the fastening portion.

  The rubber packing is not limited to various rubbers such as EPT insulating rubber, and it goes without saying that a synthetic resin flat plate such as plastic can be used as the packing without departing from the gist of the present invention.

  Further, in this embodiment, the screw hole 10b serving as a female screw is provided in the insulating resin box opening 10 and a screw 33 such as a hexagonal bolt is adopted as the male screw. A male screw may be provided and a hexagonal nut may be employed as the female screw. In this case, the pressure relief part is arranged in the order of the insulating box opening, rubber packing, and pressing metal fitting, and on the upper side, the embedded bolt is inserted into the insertion hole of the pressing metal fitting and the insertion hole of the rubber packing, On the lower side, embedded bolts are inserted only into the insertion holes of the presser fitting, and finally four hexagon nuts are fastened to form an upper first fastening portion and a lower second fastening portion. As described above, the male screw and the female screw can be appropriately selected.

  Also, in this embodiment, it is assumed that a three-phase independent space is formed, but whether to provide a single-phase or a bulky three-phase arrangement by providing a partition wall is used depending on conditions such as the installation status of the switch. It ’s fine.

  Further, one or a plurality of the above-described high-voltage switches may be housed in a cabinet for drawing underground from a high-voltage distribution line to consumers. In this case, it is possible to give flexibility to the busbars and cable arrangement in the cabinet corresponding to the position, shape and correlation pitch of any external connection terminal while making the configuration of the switching contact common, so the switch body and thus the cabinet Can also be reduced in size and cost.

  The above-described high-pressure switch of the present invention allows the internal pressure to be reduced by allowing the pressure release operation start pressure to be set to a low value with respect to a switch having a configuration in which a fixed electrode and a movable electrode are housed in an insulating resin box. It is possible to further reduce the size and cost while escaping to the outside promptly and preventing the scattering of damaged parts.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram of the high voltage | pressure switch of the best form for implementing this invention, Comprising: Fig.1 (a) is a front view, FIG.1 (b) is an AA sectional view. It is explanatory drawing explaining the pressure release by a high voltage switch.

Explanation of symbols

100: High voltage switch 10: Insulating resin box 10a: Insulating resin box opening 10b: Screw hole 11: Insulating link 11a: Drive shaft 12: Movable electrode 13: Support shaft 14: Movable embedded conductor 15: Movable external connection Terminal 16: Arc extinguishing cylinder 17: Fixed electrode 18: Fixed side embedded conductor 19: Fixed side external connection terminal 20: Back cover 30: Pressure release part 31: Presser fitting 31a: Presser fitting opening 31b: Insertion hole 32: Rubber Packing 32a: insertion hole 33: screw

Claims (7)

High-voltage switching that opens and closes the electric circuit between the high-voltage bus and the customer-side distribution line cable by storing the fixed electrode and the movable electrode in closed closed spaces made of insulating material, and moving the movable electrode to and from the fixed electrode. In the vessel
An insulating resin box having an insulating resin box opening;
First and second fastening portions provided in the vicinity of the insulating resin box opening;
A flat elastic body fastened by the first fastening portion;
A holding fitting that has a holding fitting opening and is fastened by the first and second fastening portions in the vicinity of the holding fitting opening;
With
With the peripheral edge surface of the insulating resin box opening and the peripheral edge surface of the presser metal opening sandwiching the peripheral part of the flat elastic body, the presser metal and the flat elastic body are fastened by the first fastening portion, and the second fastening is performed. The high-pressure switch is characterized in that only the holding metal fitting is fastened by the portion, the flat elastic body seals the insulating resin box opening, and the second fastening portion side of the flat elastic body is released and released when the internal pressure rises. . The high voltage switch according to claim 1,
The first and second fastening portions are constituted by male and female screws provided in the vicinity of the insulating resin box opening,
The flat elastic body has an insertion hole only on one side thereof,
The presser bracket has a plurality of insertion holes around the presser bracket opening,
With the peripheral edge surface of the insulating resin box opening and the peripheral edge surface of the pressing metal opening sandwiching the flat elastic body, the insertion hole of the pressing metal, the male screw passing through the insertion hole of the flat elastic body, and The male screw that passes only through the insertion hole of the presser fitting is fastened to the female screw, and the flat elastic body seals the opening of the insulating resin box. When the internal pressure rises, the side without the insertion hole of the flat elastic body is released and released. High pressure switch characterized by pressure. In the high voltage switch according to claim 1 or 2,
The fixed electrode and the movable electrode are respectively housed in a plurality of closed independent spaces formed by being separated from each other by an insulating material, and the movable electrode moves in a direction perpendicular to the parallel arrangement direction of the plurality of independent spaces. High pressure switch. In the high voltage switch according to any one of claims 1 to 3,
A movable-side external connection terminal electrically connected to the movable electrode via the movable-side embedded conductor;
A fixed-side external connection terminal electrically connected to the fixed electrode via the fixed-side embedded conductor;
Embedded in a resin insulation box and integrally disposed. In the high voltage switch according to any one of claims 1 to 4,
A high-voltage switch characterized in that the fixed electrode is formed by a pair of finger contacts and the movable electrode is formed by a single blade contact. In the high voltage switch according to any one of claims 1 to 5,
An insulating resin box is formed of an epoxy resin, and a flat elastic body is formed of an insulating EPT rubber.   A cabinet in which a plurality of the high-voltage switches according to any one of claims 1 to 6 are accommodated.

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