JP5997320B1 - Air switch - Google Patents

Abstract

Disclosed is a switch having a small size and excellent arc extinguishing performance while being an air insulation system. The switch body box 1 is provided with a fixed electrode 4 surrounded by an arc extinguishing chamber 6 and a rotatable movable electrode 5 which is in contact with and away from the fixed electrode 4. In an air switch that is manually or electrically operated via a drive mechanism, a switch is provided with a pair of movable electrode 5, fixed electrode 4, and a substantially sealed insulating box 7 covering the arc extinguishing chamber 6 surrounding the fixed electrode 4. Constantly provided in the main body box 1 for each of the three phases, provided with a pressure relief port 9 on the side wall of the arc-extinguishing chamber 6 opposite to the entrance / exit side of the movable electrode 5 and connected to one end of the pressure relief port 9 A long duct 11 was provided, the duct 11 penetrated the side wall of the insulating box 7 and led out of the insulating box 7, and the other end was opened in the switch body box 1. [Selection] Figure 1

Description

The present invention relates to an air switch that is small in size and has excellent arc extinguishing performance while being an air insulation system, and is oriented toward cost reduction.

For high-voltage load switches, SF ₆ gas insulation type switches have been developed for the purpose of downsizing and cost reduction. The SF ₆ gas, that is, sulfur hexafluoride gas, is a gas having excellent electric insulation performance, and the entire apparatus can be miniaturized by using it as an insulating medium. In addition, sulfur hexafluoride gas has a high arc extinguishing ability and is widely used in large-capacity circuit breakers.

However, since sulfur hexafluoride gas is a greenhouse gas, there is an increasing need to change to another method in order to reduce environmental impact.

As switch other types, but aerial switches have been conventionally used, it will be inevitably large since the insulating performance is poor, there is a problem in terms of handling and cost.

Therefore, as shown in Patent Document 1, a high-pressure air switch has been developed in which an insulating frame is incorporated inside the outer box of the switch to improve insulation and reduce the size. The insulating frame of this switch is of a box shape with an open upper surface, and the inside is partitioned by a partition wall, and fixed contacts and other parts for each phase are attached to each partition.

Moreover, the air switch shown in patent document 2 was developed. The air switch of Patent Document 2 has a stationary contact and an opening housed in a housing case, and an arc-extinguishing chamber portion made of an insulating material surrounding the stationary contact and pivoted into the housing case. A movable contact that is inserted into and removed from the arc-extinguishing chamber through the opening and is in contact with and away from the fixed contact; and the pressure in the arc-extinguishing chamber is increased by communicating with the arc-extinguishing chamber. A buffer chamber portion is provided which forms a buffer chamber that relaxes the rate of increase and decrease of the pressure when the pressure is lowered and when the pressure is lowered, thereby reducing the size of the switch.

JP-A-7-130250 JP 2001-229789 A

However, the thing of patent document 1 is what the upper surface of the insulating frame opened, and the said insulating frame is not a sealed box type thing, but is a thing with low insulation. In addition, no measures are taken such as enhancing the arc extinguishing performance against an arc generated when the movable electrode leaves the fixed electrode.

Moreover, the thing of patent document 2 is suppressing what a hot gas and an arc blow off suddenly from an arc-extinguishing chamber in the direction of a movable electrode by providing a buffer chamber, and does not extinguish an arc actively. Absent.

Therefore, in-air switches have been developed that are small and have excellent arc-extinguishing performance and can reduce costs, but have not yet been satisfactory.

Therefore, the present invention pays attention to this point, and an object thereof is to provide a switch having a small size and an excellent arc extinguishing performance while being an air insulation system.

According to the first aspect of the present invention, a fixed electrode surrounded by an arc extinguishing chamber is provided in a switch body box, and a rotatable movable electrode that contacts and separates from the fixed electrode. In an air-operated switch that is operated manually or electrically via a pair of movable and fixed electrodes and a substantially sealed insulating box made of a polymer material covering an arc extinguishing chamber surrounding the fixed electrode. Provided for each of the three phases in each, provided a pressure relief port on the side wall of the arc-extinguishing chamber opposite to the movable electrode entrance / exit side, provided a fixed-length tube having one end connected to the pressure relief port, The tube is led out of the insulating box through an opening provided in the side wall of the insulating box, the other end is opened in the switch body box, and the movable electrode is separated from the fixed electrode in the arc extinguishing chamber. The internal pressure rises due to the arc energy generated in the insulation box, and the internal pressure is Derived outside the insulating box through said tube body from said pressure port discharge arcing chamber in the box, aerial is configured to quickly cut the arc by extending the arc to the outlet by the flow of the gas A switch was used.

According to a second aspect of the present invention, in the air opening and closing according to the first aspect , the movable electrode comprises two blades sandwiching the fixed electrode, and a leaf spring is superposed on the outside of each of the two blades. It was a vessel.

According to a third aspect of the present invention, there is provided the air switch according to the first or second aspect , wherein a magnetic plate that guides the arc by electromagnetic force is provided at a location close to the pressure relief opening in the arc extinguishing chamber. did.

According to a fourth aspect of the present invention, there is provided the air switch according to any one of the first to third aspects, wherein an open / close shutter for sealing the fixed electrode is provided beside the fixed electrode in the arc extinguishing chamber.

According to the inventions of claims 1 to 4 , the switch body box is provided with a substantially sealed insulating box that covers the pair of fixed and movable electrodes, and further covers the fixed electrode in the insulating box. By providing a pressure release port for releasing pressure and extending the arc in the arc extinguishing chamber, it is possible to improve the shut-off performance and realize a small and inexpensive load switch that is an air insulation system.

In other words, when the movable electrode is opened, the internal pressure rise due to the arc energy generated between the electrodes is released from the pressure release port, and the arc is actively stretched out of the pressure release port by the gas flow, thereby quickly cutting the arc. This increases the arc extinguishing effect. Further, a pipe body is connected to the outside of the pressure release port to increase the arc extinguishing effect through the pipe body and to prevent a ground fault to the switch body box (made of metal or the like).

The polymer material constituting the insulating box is excellent in electrical insulation, heat resistance, water repellency, etc., and can maintain electrical insulation for a long time.

In particular, according to the invention of claim 2 , the movable electrode is made of two spaced blades that can sandwich the fixed electrode, and a plate spring is superposed on the outside of each of the two blades. By doing so, the contact pressure to the fixed electrode and the contact pressure of the rotating portion of the movable electrode can be secured at the same time while being simple and compact. Furthermore, the number of parts can be reduced and the cost can be reduced.

In particular, according to the invention of claim 3 , by providing the magnetic plate for inducing the arc by electromagnetic force in the arc extinguishing chamber, the effect of drawing the arc generated when the movable electrode is opened into the pressure release port is increased. It is possible to cope with a relatively large current interruption.

In particular, according to the invention of claim 4 , by providing an open / close shutter for sealing the fixed electrode in the arc extinguishing chamber, it is possible to easily cut off the low current and low power factor current.

It is a longitudinal cross-sectional front view of the state in which the movable electrode of the air switch of Embodiment 1 of this invention is thrown into the fixed electrode. It is a longitudinal cross-sectional side view of the state in which the movable electrode of the air switch of Embodiment 1 of this invention is thrown into the fixed electrode. It is a partial longitudinal cross-section side view of arc extinguishing chamber vicinity of the state which the movable electrode of the air switch of Embodiment 1 of this invention is open | released from the fixed electrode, and the opening-and-closing shutter is closed. It is an expanded partial longitudinal cross-section side view of arc extinguishing chamber vicinity of the state which the movable electrode of the air switch of Embodiment 1 of this invention was open | released from the fixed electrode, and the opening-and-closing shutter was opened. It is a figure which shows the movable electrode of the air switch of Embodiment 1 of this invention, (a) A figure is a front view, (b) A figure is a side view. It is a longitudinal cross-sectional front view which shows the state immediately after the movable electrode of the air switch of Embodiment 1 of this invention was open | released from the fixed electrode.

(Embodiment 1)
The air switch according to Embodiment 1 of the present invention will be described below.

As shown in FIG. 1, the bushing 2 and 3 which penetrated the said switch main body box 1 are provided in the upper and lower positions which oppose each other of the metal switch main body box 1, The upper bushing 2 of these is provided. The fixed electrode 4 is provided at the end in the switch body box 1, and the rotating shaft 5 a of the movable electrode 5 is provided at the end of the lower bushing 3 in the switch body box 1, The movable electrode 5 is formed of a substantially bowl-shaped blade, and the tip of the movable electrode 5 can be brought into contact with and separated from the fixed electrode 4.

Further, the fixed electrode 4 is provided at one end in a resin-made arc-shaped arc extinguishing chamber 6 having excellent arc extinguishing performance, and the tip of the movable electrode 5 is extinguished from an opening hole in the lower surface of the arc extinguishing chamber 6. It enters the arc chamber 6 and is in contact with the fixed electrode 4.

An insulating box 7 that covers the fixed electrode 4, the movable electrode 5, and the arc extinguishing chamber 6 is provided in the switch body box 1. The insulating box 7 is made of a polymer material such as silicone rubber that is excellent in electrical insulation, heat resistance, water repellency, etc., and can maintain electrical insulation for a long time even if there is internal fouling due to current switching. In addition, the insulating box 7 is provided for three phases separately for each of the three phases or having a phase interval wall, has an opening for each phase, and includes an opening / closing lid 7a covering each opening. Provided. Accordingly, the insulating box 7 has an insertion opening for the insulating drive rod 8 of the movable electrode 5, but is almost sealed for each phase.

The movable electrode 5 is rotatably connected to an insulating drive rod 8 that is moved by a drive mechanism (not shown) provided in the switch body box 1. The insulating drive rod 8 is led out of the insulating box 7 through an opening provided on the lower surface of the insulating box 7, and the lower end thereof is pivotally supported by the drive mechanism (not shown). This drive mechanism is driven manually or electrically to move the insulating drive rod 8, whereby the movable electrode 5 rotates about the rotation shaft portion 5 a, and the tip of the movable electrode 5 can be brought into contact with and separated from the fixed electrode 4.

The arc extinguishing chamber 6 is in contact with the lower surface of the top plate of the insulating box 7, and the pressure is released to the side opposite to the fixed electrode 4 in the arc extinguishing chamber 6 and to the side opposite to the opening hole through which the movable electrode 5 enters and exits. A mouth 9 is provided. An opening 10 is also provided in the top plate of the insulating box 7 facing the pressure release port 9, and the opening 10 communicates with the pressure release port 9.

One end 11a of a duct 11 having a certain length made of resin having excellent arc extinguishing performance is connected to the pressure relief opening 9 and the opening 10, and the other end 11b of the duct 11 is an upper portion of the insulating box 7. The opening of the other end 11b of the duct 11 is located below the insulating box 6 in the switch body box 1.

Further, in the arc extinguishing chamber 6 around the pressure release port 9 of the arc extinguishing chamber 6, a “U” -shaped magnetic plate 12 facing downward is provided. This magnetic plate 12 induces an arc generated when the movable electrode 5 is detached from the fixed electrode 4 by electromagnetic force.

Further, an open / close shutter 13 for sealing the fixed electrode 4 is provided in the arc extinguishing chamber 6. As shown in FIG. 3, the opening / closing shutter 13 is provided in a moving passage of the movable electrode 5 that communicates with the fixed electrode 4 in the arc extinguishing chamber 6, and moves to the left and right to open and close the passage. 3 shows a state in which the opening / closing shutter 13 is closed, and FIG. 4 shows a state in which the opening / closing shutter 13 is opened.

Then, when the low-current, low power factor current is interrupted by the open / close shutter 13, the arc is interrupted by closing the open / close shutter 13 when the movable electrode 5 is separated from the fixed electrode 4, and the low current, low The power factor current can be easily cut off.

A sheet-like insulating barrier 14 having a width larger than the thickness of the movable electrode 5 is provided on the side surface of the movable electrode 5 in the insulating box 7, and the insulating barrier 14 is provided when the movable electrode 5 is opened. The movement of the arc causes the arc to be driven into the pressure relief opening 9 at the top of the arc extinguishing chamber 6.

Next, the detailed structure of the movable electrode 5 will be described with reference to FIG. The movable electrode 5 is composed of two blades 5b and 5b. The movable electrode 5 is provided with a spacer 15 therebetween and spaced from each other, and a plate spring 16 is overlapped on each outer side of the two blades 5b and 5b. Is fixed. And although it has the structure which clamps the said fixed electrode 4 with the front-end | tip part of two blades 5b and 5b, the said fixed spring 4 is inserted | pinched with an appropriate pressing force by each said leaf | plate spring 16, Moreover, the contact pressure to the axis | shaft (electrode) of the said rotating shaft part 5a is ensured simultaneously.

With the above configuration, when the movable electrode 5 moves away from the fixed electrode 4 in the arc extinguishing chamber 6, an arc is generated between these electrodes. Then, the arc energy increases the internal pressure of the arc extinguishing chamber 6, but as shown by the arrow P in FIG. As shown in FIG. 6, the arc can be positively stretched out of the pressure release port 9, and the arc can be quickly cut to increase the arc extinguishing effect.

Further, arc-extinguishing gas is generated from the duct 11 in the duct 11, thereby increasing the arc-extinguishing effect. In addition, by providing the duct 11 having a certain length in this way, a ground fault to the switch body box 1 can be prevented.

In the first embodiment, the rotation shaft portion 5a of the fixed electrode 4 and the movable electrode 5 is provided in the vertical direction. However, the direction of the rotation shaft portion 5a of the fixed electrode 4 and the movable electrode 5 of the present invention. Is not limited to this.

In the first embodiment, the insulating box 7 is integrally provided with a packing such as a bushing penetrating portion of the switch body box 1, an internal part such as an insulating barrier, and an external part such as a sensor attachment. These may be provided separately. Further, instead of the duct, an appropriate tube body such as a rubber tube may be used. Further, folds for electrical insulation may be integrally formed on the inner surface of the insulating box 7.

1 Switch body box 2 Bushing 3 Bushing 4 Fixed electrode
5 Movable electrode 5a Rotating shaft 5b Blade
6 Arc-extinguishing chamber 7 Insulation box 7a Open / close lid 8 Insulation drive rod 9 Pressure release port 10 Opening portion 11 Duct 11a One end
11b Other end 12 Magnetic plate 13 Opening / closing shutter 14 Insulating barrier
15 Spacer 16 Leaf spring

Claims (4)

The switch body box is provided with a fixed electrode surrounded by an arc extinguishing chamber and a rotatable movable electrode that is in contact with and away from the fixed electrode. The contact and separation of the movable electrode is performed manually or electrically via a drive mechanism. In the air switch to perform,
A pair of movable and fixed electrodes and a substantially sealed insulating box made of a polymer material covering an arc extinguishing chamber surrounding the fixed electrode are provided for each of the three phases in the switch body box,
In the arc extinguishing chamber, a pressure relief port is provided on the side wall on the opposite side of the movable electrode,
A fixed-length tubular body having one end connected to the pressure release port is provided, the tubular body is led out of the insulating box through an opening provided in a side wall of the insulating box, and the other end is disposed in the switch body box. Open to
An increase in internal pressure due to arc energy generated when the movable electrode moves away from the fixed electrode in the arc-extinguishing chamber is received in the insulating box, and the internal pressure is passed through the tubular body from the discharge port of the arc-extinguishing chamber in the insulating box. An air switch which is led out of the insulating box and is configured to quickly cut the arc by extending the arc to the discharge port by the gas flow . 2. The air switch according to claim 1, wherein the movable electrode includes two blades sandwiching the fixed electrode, and a leaf spring is superposed on the outside of each of the two blades. The air switch according to claim 1 or 2, wherein a magnetic plate that induces an arc by electromagnetic force is provided at a location in the arc extinguishing chamber adjacent to the pressure release port. The air switch according to any one of claims 1 to 3, wherein an open / close shutter is provided beside the fixed electrode in the arc extinguishing chamber to seal the fixed electrode portion.

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