JP3432678B2 - Cased switchgear - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cased switch, and more particularly, to a cased switch having a pressure relief port on the wall of the case. 2. Description of the Related Art Conventionally, a cased switch is provided with a pressure relief port on the wall of the case, and when the pressure inside the case increases due to the occurrence of an abnormal voltage due to a short circuit between phases, the internal pressure becomes high. The pressure was released from the pressure relief port to the outside to prevent damage to the case itself. That is, in normal times, the pressure relief port is closed with a pressure relief lid, and when the internal pressure rises, the pressure relief lid is pushed outward by the pressure, and the pressure relief lid and the edge of the pressure relief port are pressed. The pressure was released outside the case through the gap formed in the case. The opening position of the pressure relief port is set so that the pressure release direction is set to a direction that does not affect the adjacent devices as much as possible in consideration of the external environment of the cased switch. . [0003] However, the conventional cased switch described above has the following problems. That is, when an interphase short-circuit occurs in the case, the arc generated by the short-circuit may be transferred to the case wall, which is a conductor, and a burnout hole may be formed in the wall. for that reason,
The high pressure inside the case, which has risen due to arcing, is released from the hole, and the pressure cannot be released from the discharge port set in consideration of the external environment of the case. There was a risk of adverse effects. SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is possible to reliably release the internal pressure of a case from a discharge port formed in advance when an internal pressure rises due to a short circuit between phases in a cased switch. It is an object. [0005] In order to achieve the above-mentioned object, a first aspect of the present invention is to provide a pressure relief port at a predetermined position on a case wall, and to provide a pressure relief port on the case wall provided with the pressure relief port . A cased switch provided with an arc guide member on the inner surface side ,
The arc guide member has an arc generated between two phases.
The arc guiding member is disposed between the phases so as not to migrate to the wall surface, and the arc guiding member discharges the arc along the arc guiding member.
The gist of the invention is that it extends in the in-phase direction in a long shape so as to be guided to the pressure port, and one end thereof is extended to a position at the center of the pressure release port. According to the first aspect of the present invention, the arc generated inside the case due to the interphase short-circuit is transferred to the arc guide member, and the arc energy generated at the time of the arc transfer together with the discharge gas is in the vicinity of the arc guide member. It is released from the pressure relief port to the outside of the case. Further, when an arc is generated between two adjacent phases due to an interphase short circuit, the arc is promptly transferred to the arc guide member located between the two phases in which the short circuit accident has occurred. Further, the arc transferred to the arc guide member is guided to the position of the center of the pressure relief port in the case along the long arc guide member. Next, an embodiment in which the present invention is embodied in a cased gas switch will be described with reference to the drawings. As shown in FIGS. 1 and 2, the main body case 12 of the cased gas switch 11 is formed in a box shape, and the main body case 12 is filled with an insulating gas such as sulfur hexafluoride. . Three power supply-side bushings 13 are attached to the upper wall of the main body case 12 in parallel, and the lower end of each bushing 13 is connected to the power supply-side conductor 1 so as to extend into the main body case 12.
4 are provided. A power distribution cable (not shown) is electrically connected to each power conductor 14, and a fixed electrode 15 is provided at the tip of each power conductor 14 in the main body case 12. On the other hand, three load-side bushings 16 are attached to the lower wall of the main body case 12 in parallel so as to correspond to the power supply-side bushings 13. A load-side conductor 17 is provided at an upper end of each load-side bushing 16 so as to extend into the main body case 12, and a load-side power distribution cable (not shown) is electrically connected to each load-side conductor 17. Also, each load side conductor 1
Connection conductors 18 are respectively attached to the distal ends of the connection conductors 7 by fixing bolts 19, and the base ends of the movable electrodes 21 are rotatably supported on the distal ends of the respective connection conductors 18 via rotation pins 20. Have been. Each movable electrode 21 is composed of a pair of movable contact blades 22, and the fixed electrode 15 is pressed by the two movable contact blades 22 when the movable electrode 21 is closed. A distal end of a drive lever 24 linked to an opening / closing mechanism 23 is provided between the two movable contact blades 22 of each movable electrode 21 by a connecting pin 2.
5 so as to be rotatable. That is, each movable electrode 21 is moved toward and away from the fixed electrode 15 by the opening and closing operation of the drive lever 24 interlocked with the driving of the opening and closing mechanism 23. The power-side conductor 14, fixed electrode 15, movable electrode 21, connection conductor 18, and load-side conductor 17
Constitutes the opening / closing section A. In the side wall of the main body case 12, the side wall 1 opposite to the opening / closing mechanism 23 with the opening / closing portion A interposed therebetween.
2a, a pressure relief port 26 is provided at a position slightly below the center thereof.
Are formed. The pressure release port 26 has a pressure release lid 27.
Is covered. When the internal pressure of the main body case 12 becomes high due to the occurrence of an abnormal voltage due to the interphase short circuit, the internal pressure pushes the pressure release lid 27 to the outside.
Pressure can be released to the outside of the main body case 12 from a gap formed between the pressure release port 26 and the pressure release lid 27. Further, a support bracket 28 made of an insulating material is mounted on the inner surface of the side wall 12a of the main body case 12 above the pressure release port 26 so as to extend in the interphase direction. On this support bracket 28, long rectangular pole-shaped arc electrodes 29a, 29b made of a conductive material such as copper are suspended and supported so as to extend in the same phase direction at substantially the center of each phase as an arc guide member. . The lower end of each arc electrode 29 extends to a position near the inside of the pressure release port 26. Therefore, as shown in FIG. 1, the arc electrode 29 is arranged in parallel with the opening / closing section A in the main body case 12 and is interposed between the side wall 12 a of the case 12 and the opening / closing section A. Next, the operation of the cased switch 11 constructed as described above will be described. As shown in FIG. 1, when a short-circuit accident occurs between the phases inside the main body case 12 in the closed state where the fixed electrode 15 and the movable electrode 21 are in contact with each other, an arc is generated between the two phases that caused the short-circuit accident. . For example, when two phases of the leftmost opening / closing part A1 and the central opening / closing part A2 in FIG. 2 are short-circuited and an arc I occurs between the two phases, the arc I is applied to the left arc electrode 29a in FIG. Transition. That is, as is apparent from FIG. 1, the arc electrode 29 is interposed between the side wall 12a of the case 12 and the opening / closing portion A as described above. Therefore, the arc I generated between the two phases of the opening / closing portions A1 and A2 does not move to the side wall 12a of the main body case 12 until the arc I crosses the arc electrode 29a between the two phases, and as shown in FIG. Close to this arc electrode 2
Move to 9a. After the arc I is guided along the arc electrode 29a to a position near the inside of the pressure release port 26, the arc energy generated due to heat or the like at the time of the arc transition is reduced as shown by a two-dot chain line in FIG. The lid 27 is deformed. Then, based on this deformation, the pressure release lid 27 and the pressure release port 26
As shown by an arrow G in FIG. In the present embodiment, the cased switch 11 is configured as described above, and has the following effects. (1) Since the arc electrode 29 is arranged near the pressure release port 26 inside the main body case 12, the arc I generated due to the interphase short circuit does not transfer to the side wall 12a of the main body case 12. For this reason, it is possible to prevent the side wall 12a of the main body case 12 from being burned out by the arc I generated due to the interphase short-circuit, and a hole is formed at an unnecessary position. Therefore,
At the time of pressure release, the pressure can be released from the pressure release port 26 in which the opening position is set in advance in consideration of the influence on the peripheral device, so that there is no possibility that the peripheral device of the cased switch 11 is adversely affected by the released gas. (2) Further, since the arc electrodes 29a and 29b are arranged between the phases, the arc I generated between the phases can be transferred to the corresponding arc electrodes 29a and 29b when the phases are short-circuited. Therefore, the arc I generated due to the interphase short-circuit can be quickly transferred to one of the arc electrodes 29a and 29b, and the arc length accompanying the generation of high heat can be shortened, so that the generation of arc energy can be suppressed to a minimum. . (3) Further, since the lower ends of the arc electrodes 29a and 29b are extended to positions near the inside of the pressure release port 26,
The location where the arc energy is generated at the time of arc transfer can be set near the pressure relief port 26. Therefore, the arc energy generated due to the arc transfer can be quickly discharged to the outside without being trapped inside the main body case 12. (4) Since the arc electrodes 29a and 29b are arranged in parallel with the opening / closing portion A so as to extend in the same phase direction between the phases, the arc transfer from the opening / closing portion A in the event of a short-circuit between the phases is more reliably performed. It can be performed smoothly. (5) Further, since the arc electrodes 29a and 29b have a long rectangular column shape, the arc electrodes 29a and 29b can be easily attached to the support bracket 28, and the assembling work of the cased switch 11 can be easily performed. It should be noted that the present invention is not limited to the configuration of the above-described embodiment, but may be configured as follows. (A) In the above embodiment, the arc electrodes 29a and 29b are arranged in parallel with the opening / closing portion A so as to extend in the same phase direction between the phases, but the lower ends of the arc electrodes 29a and 29b are located near the inside of the pressure relief port 26. It may be inclined as long as it is extended up to it. Even with this configuration, it is possible to prevent the arc from migrating to the side wall 12a of the main body case 12 during the interphase short-circuit, and to guide the arc I to a position near the inside of the pressure relief port 26 so that the arc energy Can be released quickly. (B) In the above embodiment, the arc electrodes 29a and 29b are formed in a long rectangular column shape, but may be formed in a round bar shape or a strip shape. Even with this configuration, substantially the same effects as in the above embodiment can be obtained. (C) In the above embodiment, the arc electrodes 29a, 29
Although 9b is provided one by one, a configuration in which only one arc electrode 29 is provided inside the main body case 12 may be employed.
For example, a single plate-shaped arc electrode having a size ranging from an intermediate position between the opening / closing portions A1 and A2 in FIG. 2 to an intermediate position between the opening / closing portions A2 and A3 in FIG. Hanging support may be used. With this configuration, the operation of attaching the arc electrode to the support bracket 28 can be performed quickly. (D) In the above embodiment, the material of the arc electrodes 29a and 29b is copper. However, other conductive materials such as silver can be used as long as the material has conductivity. (E) In the above embodiment, the present invention is embodied as a cased gas switch, but may be embodied as a cased air switch. Next, technical ideas other than the claimed invention which can be understood from the above embodiment will be described together with the effects. The cased switch according to claim 1 , wherein the arc guide member extends in parallel with the switch so as to extend in the same phase direction. According to this configuration, it is possible to more reliably and smoothly transfer the arc generated from the opening / closing portion due to the interphase short circuit to the arc guide member. According to the first aspect of the present invention, when the internal pressure rises due to the short circuit between phases, the pressure relief can be reliably performed from the pressure relief port formed in advance in consideration of the external environment. It is possible to eliminate the possibility that the depressurized gas adversely affects other peripheral devices adjacent to the entrance switch. Also, at the time of arc transition
Arc length can be shortened, and
Pressure inside the case by minimizing arc energy
Can be suppressed. Furthermore, the arc generated by the arc transfer
Pressure is released without energy trapped in the case
Can be released smoothly from the mouth. [0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side sectional view of a cased gas switch of the present embodiment. FIG. 2 is also a partially cutaway schematic front view of the same. [Description of Signs] 12: Main body case, 12a: Side wall (case wall surface), 26
... pressure relief ports, 29a, 29b ... arc electrodes (arc guiding members), A ... opening and closing parts.

Claims (1)

(57) [Claims 1] A pressure relief port is provided at a predetermined position on the case wall,
A cased switch provided with an arc guide member on the inner surface side of the case wall surface provided with the pressure relief port, wherein the arc guide member is provided with an arc generated between two phases.
The arc guiding member is disposed between the phases so as not to migrate to the wall surface, and the arc guiding member discharges the arc along the arc guiding member.
A cased switch that has a long shape and extends in the same phase direction to be guided to the pressure port, and one end of the switch extends to the center of the pressure release port.