JP2016143499A - Gas circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas circuit breaker which enables smooth exhaustion of gas in any current regions and has an excellent current cut-off performance despite of low driving force.SOLUTION: A gas circuit breaker 1 guides, via an insulation nozzle 24, arc-extinguishing gas whose pressure has been accumulated in a puffer chamber 23 to arc discharge. The gas circuit breaker 1 then discharges, via an exhaustion passage, a gas flow released from an outlet of the insulation nozzle 24. The exhaustion passage is provided with a reflection portion such as a pressure rise region 40 which causes reflection waves to reflect toward the outlet of the insulation nozzle 24. The gas circuit breaker 1 further comprises a barrier 30 which is interposed, in the exhaustion passage, between the outlet of the insulation nozzle 24 and the reflection portion. The barrier 30 has an area equal to or larger than a cross section of the outlet of the insulation nozzle 24 but smaller than a cross section of the exhaustion passage. The barrier 30 avoids the reflection waves reflected on the reflection portion from reaching the outlet of the insulation nozzle 24.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a gas circuit breaker that switches between current interruption and input in a power system.

  In an electric power system, a gas circuit breaker is used when it is necessary to interrupt an excessive accident current, a small advance current, a delayed load current such as a reactor cutoff, or an extremely small accident current. The gas circuit breaker mechanically separates the movable contact portion and the opposed contact portion in the interruption process, and extinguishes the arc discharge generated in the separation process by blowing arc-extinguishing gas.

  As the above-described gas circuit breaker, a type called a puffer type is currently widely used (see, for example, Patent Document 1). In this gas circuit breaker, there are a puffer chamber in which the volume is reduced by accumulating the movable contact portion and the opposed contact portion, and the pressure is accumulated inside, and an insulating nozzle that is connected to the puffer chamber and surrounds a space where arc discharge occurs Is provided. The arc extinguishing gas accumulated in the puffer chamber is guided to the arc discharge by the insulating nozzle, so that the arc extinguishing gas is blown to the arc discharge. An exhaust passage is formed in the gas circuit breaker, and the arc extinguishing gas blown by the arc discharge and heated to a high temperature and the high-temperature gas generated from the arc discharge are exhausted by the exhaust passage.

  The gas exhaust flow path is formed by being divided into a movable contact portion and a counter contact portion. In the counter contact portion, an internal space of a cylindrical cooling cylinder that serves as a fixed support portion of the counter contact portion. It is. The cooling cylinder is open at both ends, receives the gas released from the outlet of the insulating nozzle from one end side, flows inside and discharges it from the other end side (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 5-250967 JP 2003-109476 A

  In recent years, the gas pressure accumulated in the puffer chamber in order to cut off a large current has remarkably increased. The increase in gas pressure also greatly affects the puffer piston, which is one element forming the puffer chamber. Due to the pressure acting on the puffer piston, the driving force for driving the movable contact portion against the driving reaction force is increased. For this reason, a circuit breaker using a so-called self-effect that reduces the driving reaction force by reducing the size of the puffer chamber or obtains pressure accumulation in the puffer chamber by taking in high-temperature gas by arc discharge has been developed.

  However, the mass of the arc extinguishing gas that can be sprayed decreases as the puffer chamber becomes smaller. If it does so, the density of arc-extinguishing gas will fall, and there exists a problem that the temperature of the hot gas which passes an exhaust flow path rises. A decrease in gas density leads to a decrease in dynamic pressure in the exhaust passage. The increase in hot gas temperature causes a local pressure increase, and the pressure distribution in the exhaust flow path does not decrease monotonously, but the flow rate decreases or the flow stagnates, preventing sufficient hot gas discharge. There is a risk of being.

  In particular, the arc-extinguishing gas is weakly blown when a small and medium current is interrupted. For this reason, the dynamic pressure in the exhaust passage is significantly reduced, and the hot gas may not be exhausted to the outside of the cooling cylinder. In such a case, a pressure increase region appears near the outlet of the cooling cylinder, which may cause reflection of hot gas or pressure waves. The pressure wave or hot gas reflected in the pressure rise area may flow backward toward the outlet of the insulating nozzle, creating another pressure rise area near the outlet of the insulating nozzle, and hindering good hot gas discharge from the insulating nozzle. is there.

  The gas circuit breaker according to the present embodiment has been made to solve the above-described problems, achieves smooth exhaust of gas in any current region, and has excellent current interruption performance with a small driving force. It aims at providing the gas circuit breaker which has.

  In order to achieve the above object, a gas circuit breaker according to the present embodiment is a gas circuit breaker that switches between current interruption and charging, and a closed container filled with an arc-extinguishing gas, and is opposed to the closed container. A movable contact portion and an opposing contact portion which are arranged and contact or separate from each other at the time of turning on or off, and an arc discharge is generated in the separation process; a puffer chamber for accumulating the arc extinguishing gas; and one end Is connected to the puffer chamber, has an outlet at the other end, surrounds a space where the arc discharge is generated, and guides the arc extinguishing gas discharged from the puffer chamber to the arc discharge, An exhaust passage for exhausting the gas flow containing the arc-extinguishing gas discharged from the outlet of the nozzle, and a reflection location that exists in the exhaust passage and reverses the reflected wave of the gas flow toward the outlet of the nozzle; The nozzle exits in the exhaust flow path. Between the nozzle and the reflection spot, and is equal to or larger than the cross-sectional area of the outlet of the nozzle and smaller than the cross-sectional area of the exhaust passage, and the reflected wave that has flowed back at the reflection spot reaches the nozzle outlet. And a barrier for shielding.

It is sectional drawing which shows the whole structure of the gas circuit breaker which concerns on 1st Embodiment. It is a schematic diagram which concerns on the gas circuit breaker of 1st Embodiment and shows the structure and gas flow of an opposing contact part. It is a schematic diagram which concerns on the gas circuit breaker of 2nd Embodiment and shows the structure and gas flow of an opposing contact part. It is a schematic diagram which concerns on the gas circuit breaker of 3rd Embodiment and shows the structure and gas flow of an opposing contact part. It is a schematic diagram which concerns on the gas circuit breaker of 4th Embodiment and shows the structure and gas flow of an opposing contact part.

(First embodiment)
Hereinafter, the gas circuit breaker of the first embodiment will be described with reference to FIGS. 1 and 2. The gas circuit breaker 1 opens and closes a current to protect a power transmission system and a distribution system in the event of a line ground fault or a line short circuit fault, and makes contact with and separates the contacts that make up the electric circuit and Switch off. In the current interruption process, an arc discharge is generated between the contacts. The gas circuit breaker 1 is extinguished at a current zero point by blowing an arc extinguishing gas against arc discharge. The arc extinguishing gas blown to the arc discharge is exhausted from the space where the arc discharge is generated by the exhaust passage of the gas circuit breaker. Hereinafter, the side of the contact toward the contact, in other words, the arc discharge side is referred to as the front end, and the opposite side is referred to as the rear end.

(Outline configuration)
This gas circuit breaker 1 arrange | positions a contactor in the airtight container (not shown) with which arc-extinguishing gas was filled. The sealed container is a cylindrical container such as a grounded metal or insulator. The arc extinguishing gas is, for example, sulfur hexafluoride gas (SF ₆ gas), air, carbon dioxide, oxygen, nitrogen, or a mixed gas thereof, or other gas excellent in arc extinguishing performance and insulation performance. Desirably, the arc-extinguishing gas is a single gas or a mixed gas of a gas having a global warming potential lower than that of sulfur hexafluoride gas, having a low molecular weight, and at least 1 atm and 20 degrees centigrade. is there.

  As shown in FIG. 1, a contactor is divided roughly into the opposing contactor part 10 and the movable contactor part 20, and opposes in an airtight container. The opposed contact portion 10 and the movable contact portion 20 are a composite body having a basic shape of an internal hollow cylinder or a solid column, and all the members have a concentric arrangement having a common central axis, By matching the diameters, the related members face each other and function cooperatively.

  The opposing contact portion 10 is a fixed element having an opposing arc contact 11 and an opposing energizing contact 12. The movable contact portion 20 is a movable element having a movable arc contact 21 and a movable energizing contact 22. The opposing energizing contact 12 and the movable energizing contact 22 are opposed to each other, and switching on and off of current is switched by their contact and separation. The opposed arc contact 11 and the movable arc contact 21 are opposed to each other, and the arc discharge is assumed by the separation.

  The movable contact portion 20 is movable along the central axis in the opening direction and the contact direction with respect to the opposing contact portion 10. That is, the movable contact portion 20 includes an operation rod 28 that moves on an axis by an operation force of a driving device (not shown). The movable contact portion 20 is linked to the operation rod 28. When the operating rod 28 is pushed into the opposing contact portion 10 side or pulled away from the opposing contact portion 10 side, the movable contact portion 20 contacts and separates from the opposing contact portion 10.

  A bum-kuchen-shaped puffer chamber 23 is provided around the trunk of the operating rod 28 to provide a mechanical compression action. The volume of the puffer chamber 23 is variable in conjunction with the movement of the operation rod 28, the volume decreases in the process of interrupting the current, and the arc extinguishing gas is released to the outside as the internal space accumulates pressure. An insulating nozzle 24 is connected to the puffer chamber 23 to guide the mechanically compressed arc-extinguishing gas to arc discharge. The insulating nozzle 24 surrounds the communication hole 25a that connects the puffer chamber 23 and the outside, and the movable arc contact 21 to the tip, and further extends toward the opposing contact portion 10 to have an outlet, thereby generating an arc discharge generation space. The arc extinguishing gas released from the puffer chamber 23 is guided to arc discharge.

(Detailed configuration)
Each part of the above gas circuit breaker 1 is further explained in full detail. As shown in FIG. 1, the opposing contact portion 10 includes a cooling cylinder 14 having a cylindrical shape with openings at both ends, and a support 13 that is erected on the inner peripheral surface of the cooling cylinder 14 and extends toward the central axis. As shown, the opposed energizing contact 12 and the opposed arc contact 11 are fixedly arranged.

  The opposed energizing contact 12 is a cylindrical conductor. The opposed energizing contact 12 has the same diameter as the edge of the cooling cylinder 14 on the movable contact portion 20 side, and extends toward the movable contact portion 20 with the edge of the opposed energized contact 12 superimposed on this edge. An opening edge of the tip of the opposed energizing contact 12 bulges out. The counter arc contact 11 is a cylindrical conductor whose tip is rounded. The counter arc contact 11 is supported by the support 13 at the rear end side and disposed inside the cooling cylinder 14 and extends toward the movable contact portion 20 on the central axis of the gas circuit breaker.

  The inner diameter of the cooling cylinder 14 and the inner diameter of the opposed energizing contact 12 are larger than the outer diameter of the opposed arc contact 11, and there is a space between the opposed arc contact 11, the cooling cylinder 14 and the opposed energized contact 12. 14a is formed. The arc extinguishing gas ejected from the puffer chamber 23 and guided to the arc discharge by the insulating nozzle 24 is ejected from the outlet of the insulating nozzle 24 and passes through the space portion 14a from the rear end of the cooling cylinder 14 to the opposing contact portion. Go out 10

  In the space portion 14 a of the cooling cylinder 14, a barrier 30 is provided between the rear end outlet of the cooling cylinder 14 and the outlet of the insulating nozzle 24. The barrier 30 is fitted into and supported by the counter arc contact 11. The barrier 30 is a disk having a plane perpendicular to the central axis, and spreads radially from the outer peripheral surface of the opposed arc contactor 11. The outer diameter of the barrier 30 is larger than the outer diameter of the counter arc contact 11 and smaller than the inner diameter of the cooling cylinder 14. In other words, the barrier 30 cuts off the space on the rear end outlet side of the cooling cylinder 14 and the space on the outlet side of the insulating nozzle 24 except for the outer peripheral side of the space portion 14a. The diameter of the barrier 30 is equal to or greater than the same diameter at the outlet of the insulating nozzle 24.

  Next, in the movable contact portion 20, the operation rod 28 is a hollow cylinder whose front end side is hollow and whose rear end side is solid. It is arranged on the top. The operation rod 28 is the core of the movable contact portion 20, and the rear end of the solid portion side is connected to the drive device via an insulating rod (not shown), and is pushed or pulled in the axial direction. The hollow portion of the operating rod 28 is blocked by a wall in the middle, and a communication hole 28a that connects the inside and the outside of the operating rod 28 is formed in the side peripheral wall at the tip side of the wall. The communication hole 25 a is provided behind the later-described piston 26 and at a position facing the inner peripheral surface of the piston support 27.

  The movable arc contactor 21 is a conductor having an internal hollow cylindrical shape that is open at both ends. The movable arc contact 21 has the same diameter as the operation rod 28, extends continuously from the opening edge of the operation rod 28, and makes one opening relative to the opposed arc contact 11. The opening edge of the movable arc contact 21 bulges inside. The inner diameter of the opening edge portion matches the outer diameter of the counter arc contact 11. The movable arc contact 21 is fixed to the tip of the operation rod 28, and is moved toward and away from the opposed arc contact 11 in conjunction with the operation rod 28. The opposed arc contact 11 is inserted into the opening of the movable arc contact 21. As a result, the movable arc contact 21 and the counter arc contact 11 become conductive.

  In addition, the front-end | tip of the movable arc contactor 21 may be formed as a finger-like electrode by dividing | segmenting in the circumferential direction. The movable arc contact 21 has flexibility, and the inner diameter of the opening edge of the movable arc contact 21 is slightly smaller than the outer diameter of the counter arc contact 11.

  The puffer chamber 23 is a gas flow generating means defined by a movable cylinder 25, a stationary piston 26 and an operating rod 28. The cylinder 25 is a cup-shaped conductor having one end with a bottom and the other end opened. The bottomed portion of the cylinder 25 is flush with the distal end of the operation rod 28 and is connected to the operation rod 28 so as to be connected to the proximal end of the movable arc contact 21, and moves together with the operation rod 28.

  The cylinder 25 has an inner diameter larger than the outer diameter of the operation rod 28 and has a common central axis with the operation rod 28. The bottomed portion has a disk shape and extends from the outer periphery of the tip of the operation rod 28 into a flange shape. The side peripheral wall surrounding the bottomed portion extends in the direction opposite to the facing contact portion 10. The piston 26 is a donut-shaped flat plate. The piston 26 is fitted into the cylinder 25 while the outer diameter of the piston 26 matches the inner diameter of the cylinder 25 and the operation rod 28 is slidably passed through the opening of the piston 26.

  The piston 26 is formed integrally with the piston support 27. The piston support 27 is a cylinder that extends from the piston 26 in the direction opposite to the facing contact portion 10. Located outside the operation rod 28, the inner peripheral surface of the piston support 27 faces the outer peripheral surface of the operation rod 28. The piston support 27 is not connected to the operation rod 28 and is fixed in position in the sealed container.

  A puffer chamber 23 is a space defined by the cylinder 25, the piston 26, and the operation rod 28. As the operating rod 28 moves backward, the cylinder 25 approaches the piston 26, the total length of the puffer chamber 23 is reduced, and the volume is reduced accordingly, whereby the puffer chamber 23 pressurizes the arc extinguishing gas inside. A communication hole 25 a that leads to the hollow portion of the cylinder 25 is formed in the bottomed portion of the cylinder 25 around the outer circumference of the movable arc contact 21, and the counter arc contact 11 connects the puffer chamber 23 and its outdoor space. Connect on the side.

  The insulating nozzle 24 is an internal hollow cylinder that is erected on the surface of the bottomed portion of the cylinder 25 on the side of the counter arc contact 21. The insulating nozzle 24 has an internal space in which U-shaped and V-shaped bent portions are overlapped with each other, and is a Laval nozzle in which a convergent nozzle and a divergent nozzle are combined. That is, the insulating nozzle 24 has a throat portion that is a minimum inner diameter portion that bulges inward in the middle.

  Specifically, the insulating nozzle 24 surrounds the communication hole 25a with the puffer chamber 23, and constricts the movable arc contact 21 toward the throat portion so as to wrap the movable arc contact 21 at a predetermined interval. Extends along the central axis to the side. Further, after passing through the tip of the movable arc contact 21, the insulating nozzle 24 is narrowed to an extent that the inner diameter is slightly larger than the outer diameter of the counter arc contact 11, and reaches the throat portion that becomes the minimum inner diameter portion. It expands linearly toward.

  The movable energizing contact 22 is a conductor having a cylindrical shape with an open end face. The movable energizing contact 22 has a cylindrical wall on the outer side of the insulating nozzle 24 and is erected on the bottomed portion of the cylinder 25 toward the opposing energizing contact 12. The movable energizing contact 22 faces the counter energizing contact 12. The outer diameter of the movable energizing contact 22 matches the inner diameter of the opening edge portion that bulges inside the opposing energizing contact 12. When the movable energizing contact 22 is inserted into the opening of the opposed energizing contact 12, the inner surface of the opposed energizing contact 12 and the outer surface of the movable energizing contact 22 are brought into contact with each other and become electrically conductive.

(Function)
(Blocking operation)
In the energized state, the cooling cylinder 14, the opposed energizing contact 12, the movable energizing contact 22, and the cylinder 25 are electrically connected to form an electric circuit. Although not particularly illustrated, two conductors are fixed to the opposed contact portion 10 side and the movable contact portion 20 side by spacers in the sealed container. The spacer insulates the sealed container from the conductor and supports the conductor. In the energized state, the current flows into the gas circuit breaker 1 through a bushing (not shown), and from the conductor on the opposed contact portion 10 side through the conductor and the conductor on the movable contact portion 20 side and the bushing (not shown). And flows out of the gas circuit breaker 1.

  When a ground fault or line short-circuit fault occurs in the line and an opening command is input to the gas circuit breaker 1, the gas circuit breaker 1 opens the opposed contact part 10 and the movable contact part 20. , Cut off the current. Specifically, the operating rod 28 receives the operating force of the driving device and moves along the central axis in the direction opposite to the facing contact portion 10. The movable contact portion 20 is dragged by the operation rod 28 and moves away from the opposed contact portion 10, and the opposed energized contact 12 and the movable energized contact 22 are separated.

  At this time, the bottom of the cylinder 25 connected to the operating rod 28 approaches the piston 26 whose position is fixed. Therefore, the volume of the puffer chamber 23 decreases, and the arc extinguishing gas in the puffer chamber 23 is accumulated. When the interruption operation further proceeds and the opposed arc contact 11 and the movable arc contact 21 are separated, an arc discharge is generated between the opposed arc contact 11 and the movable arc contact 21. When the interruption operation further proceeds, the distance between the opposed arc contact 11 and the movable arc contact 21 is sufficiently opened and the puffer chamber 23 is sufficiently accumulated, the arc extinguishing gas in the puffer chamber 23 passes through the communication hole 25a. It ejects into the insulating nozzle 24.

  The arc-extinguishing gas that has become a jet is guided toward the arc discharge using the gas supply path between the insulating nozzle 24 and the movable arc contact 21 and is strongly blown against the arc discharge. The arc discharge is extinguished in combination with the blowing of a strong arc extinguishing gas when the current zero point is reached. Thereby, the current interruption of the gas circuit breaker is completed.

(Exhaust arc extinguishing gas)
During the current interruption operation, the arc extinguishing gas blown to the arc discharge and the gas generated from the arc discharge are separated into the movable contact portion 20 side and the opposed contact portion 10 side and discharged as a gas flow. The On the movable contact portion 20 side, the space surrounded by the inside of the movable arc contact 21, the inside of the operating rod 28, the communication hole 28 a, and the inner peripheral surface of the piston support 27 and the outer peripheral surface of the operating rod 28 is exhausted. Functions as a road. The gas flow flows from the arc discharge generation space through the exhaust passage, is discharged out of the movable contact portion 20, and is diffused into the sealed container.

  On the other hand, as shown in FIG. 2, the space portion 14 a in the cooling cylinder 14 functions as an exhaust passage on the counter contact portion 10 side. The gas flow 51 is discharged from the outlet of the insulating nozzle 24 and enters the space 14 a in the cooling cylinder 14. Since the outlet of the insulating nozzle 24 continuously expands, the gas flow 51 is ejected so as to diffuse from the central axis toward the inner peripheral surface of the cooling cylinder 14. Therefore, the gas flow 51 bypasses the barrier 30 having the same diameter or more as the outlet of the insulating nozzle 24, passes through the gap between the inner wall surface of the cooling cylinder 14 and the barrier 30, and opens at the rear end of the cooling cylinder 14. Head to the exit.

  Here, when the medium and small currents are interrupted, the arc extinguishing gas blowing force is weak, and the dynamic pressure of the gas flow 51 in the cooling cylinder 14 is also weak. For this reason, a part of the gas flow 51 cannot be removed from the rear end of the cooling cylinder 14, and a pressure increase region 40 may be generated at the rear end of the cooling cylinder 14. This pressure rise region 40 becomes a reflection part of the gas flow 51, and a reflected wave 52 such as a gas flow and a pressure wave that flows backward from the rear end outlet of the cooling cylinder 14 toward the outlet of the insulating nozzle 24 is generated.

  However, a barrier 30 is interposed between the rear end outlet of the cooling cylinder 14 and the outlet of the insulating nozzle 24. The barrier 30 stops the reflected wave 52 before reaching the exit of the insulating nozzle 24. Therefore, the reflected wave 52 does not reach the outlet of the insulating nozzle 24 and does not hinder arc extinguishing gas discharge from the insulating nozzle 24. That is, in this gas circuit breaker 1, even if the pressure increase region 40 is generated at the rear end portion of the cooling cylinder 14, another pressure increase region is not generated in the vicinity of the outlet of the insulating nozzle 24. Good high heat arc extinguishing gas emissions are maintained.

(effect)
As described above, the gas circuit breaker 1 is configured such that the movable contact portion 20 and the opposed contact portion 10 are arranged to face each other in an airtight container filled with an arc extinguishing gas, and arc discharge is generated in the process of opening. By the insulating nozzle 24 surrounding the space where the arc-extinguishing gas is ejected from the puffer chamber 23 for accumulating the arc-extinguishing gas, one end is connected to the puffer chamber 23 and the other end has an outlet. The arc extinguishing gas is guided to arc discharge. The arc extinguishing gas guided by the arc discharge forms a gas flow 51 together with the gas generated from the arc discharge, is discharged from the outlet of the insulating nozzle 24, and the exhaust flow of the gas circuit breaker 1 together with the gas generated from the arc discharge. Exhausted by the road.

  At this time, there may be a reflection location in the exhaust passage that reflects the reflected wave 52 toward the outlet of the insulating nozzle 24. However, the gas circuit breaker 1 includes a barrier 30 interposed between the outlet of the insulating nozzle 24 and the reflection portion in the exhaust passage. The barrier 30 is equal to or larger than the cross-sectional area of the outlet of the insulating nozzle 24 and smaller than the cross-sectional area of the exhaust passage, and blocks the reflected wave 52 from reaching the outlet of the insulating nozzle 24.

  In the first embodiment, the reflection location includes the cooling cylinder 14, and is a pressure increase region 40 generated at the outlet of the cylindrical portion that surrounds the outlet of the insulating nozzle 24 on one end side and opens on the other end side, and the barrier 30 is The cooling cylinder 14 is erected and is interposed between the outlet of the insulating nozzle 24 and the pressure increase region 40.

  As a result, a separate high pressure region does not occur near the exit of the insulating nozzle 24 even by the reflected wave 52 from the reflection location, and good discharge of the high heat extinguishing gas from the arc discharge generation space is maintained. The good current interruption performance of the gas circuit breaker 1 is maintained.

(Second Embodiment)
Hereinafter, the gas circuit breaker of the second embodiment will be described with reference to FIG. The same configurations and the same functions as those of the gas circuit breaker according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(Constitution)
As shown in FIG. 3, the gas circuit breaker 1 has a truncated cone member 32 disposed in the space portion 14 a of the cooling cylinder 14. The truncated cone member 32 is fitted in the counter arc contact 11. The small-diameter plane is the same as the diameter of the opposed arc contact 11 and faces the outlet of the insulating nozzle 24. The rear end surface of the truncated cone member 32 is a barrier 30, and the peripheral surface is a flow guide 31. That is, the flow guide 31 is interposed between the barrier 30 and the insulating nozzle 24 and continuously increases in diameter from the outlet side of the insulating nozzle 24 toward the rear end of the cooling cylinder 14 until the diameter becomes equal to or larger than the barrier 30. doing.

(Function)
As shown in FIG. 3, in this gas circuit breaker 1, the gas flow 51 discharged from the outlet of the insulating nozzle 24 is guided by the flow guide 31 to accelerate the velocity component in the radial direction of the cooling cylinder 14, and the cooling cylinder 14 toward the inner peripheral surface from the central axis. The inner peripheral surface side of the cooling cylinder 14 is not blocked by the barrier 30, and the space on the outlet side of the insulating nozzle 24 and the space on the outlet side of the cooling cylinder 14 communicate with each other. Therefore, it is possible to suppress the movement of the gas flow 51 that is discharged from the outlet of the insulating nozzle 24 and travels toward the rear end of the cooling cylinder 14 from being blocked by the barrier 30, and the barrier 30 closes the outlet of the insulating nozzle 24. It can suppress that a pressure rise area | region will be formed. Further, since the gas flow 51 increases the speed by the flow guide 31, smooth exhaust is realized even when the dynamic pressure at the time of interrupting the medium / small current is low.

(effect)
As described above, the gas circuit breaker 1 includes the flow guide 31 between the barrier 30 and the outlet side of the insulating nozzle 24. The flow guide 31 continuously expands from the outlet side of the insulating nozzle 24 until it becomes equal to or larger than the diameter of the barrier 30. Thereby, it is possible to suppress the pressure increase region from being formed near the outlet of the insulating nozzle 24 by the barrier 30. Further, even when the dynamic pressure at the time of interrupting the medium / small current is low, smooth exhaust is realized.

(Third embodiment)
A gas circuit breaker according to a third embodiment will be described with reference to FIG. The same configurations and the same functions as those of the gas circuit breaker according to the first or second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(Constitution)
As shown in FIG. 4, the gas circuit breaker 1 includes double cooling cylinders 14 and 15. That is, the second cooling cylinder 15 is installed in the sealed container so as to surround the cooling cylinder 14. The second cooling cylinder 15 is a cup-shaped cylinder with one end surface having a bottom and the other end surface opened, and has an inner diameter larger than that of the cooling cylinder 14, with the bottom surface 15 a facing the rear end outlet of the cooling cylinder 14. The cooling cylinder 14 is accommodated inside.

  The bottomed surface 15a of the second cooling cylinder 15 and the rear end outlet of the cooling cylinder 14 are separated from each other to form a first separation portion 15b, and the inner surface of the side peripheral wall of the second cooling cylinder 15 and the side peripheral wall of the cooling cylinder 14 are formed. The outer surface is also spaced apart to form a second spacing portion 15c. In this gas circuit breaker 1, the exhaust flow path of the gas flow 51 on the facing contact portion 10 side is composed of the space portion 14 a, the first separation portion 15 b, and the second separation portion 15 c of the cooling cylinder 14.

(Function)
The reflection location where the reflected wave 52 is generated can be generated not only by the pressure increase region but also by the configuration of the gas circuit breaker 1. In this gas circuit breaker 1, the flow direction of the gas flow 51 in the space portion 14 a of the cooling cylinder 14 is closed by the bottomed surface 15 a of the second cooling cylinder 15. For this reason, the bottomed surface 15 a becomes a reflection portion that causes the reflected wave 52 to flow backward toward the outlet of the insulating nozzle 24.

  However, also in this gas circuit breaker 1, the frustum member 32 having the barrier 30 or the barrier 30 and the flow guide 31 is interposed between the bottomed surface 15 a of the second cooling cylinder 15 and the outlet of the insulating nozzle 24. This suppresses the reflected wave 52 reflected by the bottomed surface 15a of the second cooling cylinder 15 from reaching the outlet of the insulating nozzle 24 and prevents a new pressure increase region from being generated near the outlet of the insulating nozzle 24. be able to.

  As described above, the gas circuit breaker 1 surrounds the cooling cylinder 14, which is the first cylindrical portion that surrounds the outlet of the insulating nozzle 24 on one end side and is open on the other end side, and the cooling cylinder 14. A second cooling cylinder 15 that is a cup-shaped cylindrical portion having a bottomed surface 15a facing the opening formed at the rear end is provided. In this gas circuit breaker 1, the exhaust passage communicates with the inside of the cooling cylinder 14 and the opening on the rear end side of the cooling cylinder 14, and the outer peripheral surface of the cooling cylinder 14 and the inner peripheral surface of the second cooling cylinder 15. It will be formed by the inside defined by.

  At this time, the reflection location is the bottomed surface 15 a of the second cooling cylinder 15, but the barrier 30 is erected inside the cooling cylinder 14, the outlet of the insulating nozzle 24 and the bottomed surface 15 a of the second cooling cylinder 15. By interposing between them, good discharge of the high heat extinguishing gas from the arc discharge generation space is maintained, so that the good current interruption performance of the gas circuit breaker 1 is maintained.

(Fourth embodiment)
A gas circuit breaker according to a fourth embodiment will be described with reference to FIG. The same configurations and the same functions as those of the gas circuit breaker according to the first or second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 5, the gas circuit breaker 1 is closed at the rear end of the cooling cylinder 14. That is, the rear end of the cooling cylinder 14 is a bottomed surface 14b. The cooling cylinder 14 is formed with a plurality of holes that communicate between the inside and the outside. In the cooling cylinder 14, the direction of the gas flow 51 that flows in the central axis direction is changed so that the plurality of holes correspond to the opposing contact portion 10. It is designed to be released outside.

  The reflection location of the gas circuit breaker 1 is the bottomed surface 14 b of the cooling cylinder 14, and the downstream exhaust tends to stagnate in the vicinity of the bottomed surface 14 b, and the reflected wave 52 can easily flow backward toward the outlet of the insulating nozzle 24. However, in this gas circuit breaker 1 as well, the barrier 30 or the truncated cone member 32 having both the barrier 30 and the flow guide 31 is interposed between the bottom surface 14b of the cooling cylinder 14 and the outlet of the insulating nozzle 24, thereby cooling. The reflected wave 52 reflected by the bottomed surface 14 b of the cylinder 14 can be prevented from reaching the outlet of the insulating nozzle 24, and a new pressure increase region can be prevented from being generated near the outlet of the insulating nozzle 24.

  As described above, the gas circuit breaker 1 includes the cooling cylinder 14 that is a cylindrical portion that surrounds the outlet of the insulating nozzle 24 on one end side and has a bottom on the other end side, and the reflection location is the bottomed surface 14 b of the cooling cylinder 14. It becomes. In this case, the barrier 30 is erected inside the cooling cylinder 14 and is interposed between the outlet of the insulating nozzle 24 and the bottomed surface 14b of the cooling cylinder 14, so that a good discharge from the arc discharge generation space can be obtained. Since the discharge of the high heat arc extinguishing gas is maintained, the good current interruption performance of the gas circuit breaker 1 is maintained.

(Other embodiments)
In the present specification, an embodiment according to the present invention has been described. However, this embodiment is presented as an example, and is not intended to limit the scope of the invention. Combinations of all or any of the configurations disclosed in the embodiments are also included. The above embodiments can be implemented in other various forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

  For example, the gas circuit breaker according to this embodiment or the modification is configured to fix the opposed contact portion 10 and move only the movable contact portion 20 in the axial direction. A so-called dual motion mechanism may be employed in which the opposing contact portion 10 is also moved in the axial direction so that the child portion 20 moves relatively, thereby improving the relative opening speed.

  Further, as the gas flow generating means, a heat puffer chamber may be employed instead of the puffer chamber 23, or a serial puffer type using both the puffer chamber 23 and the heat puffer chamber may be employed. The thermal puffer chamber is a gas flow generating means for accumulating the arc-extinguishing gas in the room by using the thermal energy of the arc-extinguishing gas that has been heated by arc discharge.

DESCRIPTION OF SYMBOLS 1 Gas circuit breaker 10 Opposing contact part 11 Opposing arc contact 12 Opposing energizing contact 13 Support 14 Cooling cylinder 14a Space part 14b Bottom surface 15 Second cooling cylinder 15a Bottom surface 15b First separation part 15c Second separation Part 20 Movable contact part 21 Movable arc contactor 22 Movable energizing contactor 23 Puffer chamber 24 Insulating nozzle 25 Cylinder 25a Communication hole 26 Piston 27 Piston support 28 Operation rod 28a Communication hole 30 Barrier 31 Flow guide 32 Frustum member 40 Pressure rise Region 51 Gas flow 52 Reflected wave

Claims (5)

A gas circuit breaker that switches between current interruption and input,
A sealed container filled with arc-extinguishing gas;
A movable contact portion and an opposing contact portion, which are disposed opposite to each other in the closed container, contact or separate from each other at the time of charging or shutting off, and arc discharge is generated in the process of separation;
A puffer chamber for accumulating the arc extinguishing gas;
A nozzle having one end connected to the puffer chamber and having an outlet at the other end, surrounding a space where the arc discharge is generated, and guiding the arc-extinguishing gas discharged from the puffer chamber to the arc discharge;
An exhaust passage for exhausting a gas flow containing the arc-extinguishing gas discharged from the outlet of the nozzle;
A reflection location that exists in the exhaust flow path and reverses the reflected wave of the gas flow toward the outlet of the nozzle;
In the exhaust passage, it is interposed between the outlet of the nozzle and the reflection portion, and is equal to or larger than the sectional area of the outlet of the nozzle and smaller than the sectional area of the exhaust passage, and flows backward at the reflection portion. A barrier that blocks the reflected wave from reaching the outlet of the nozzle;
Providing
A gas circuit breaker characterized by The outlet of the nozzle is surrounded on one end side, the other end side is open, and includes a cylindrical portion that forms the exhaust passage inside.
The reflection spot is a pressure increase region generated at the other end side outlet of the cylindrical portion,
The barrier is erected inside the cylindrical portion and interposed between the outlet of the nozzle and the pressure increase region;
The gas circuit breaker according to claim 1. Surrounding the outlet of the nozzle on one end side, the other end side is bottomed, and includes a cylindrical portion that forms the exhaust passage inside,
The reflection portion is a bottomed portion on the other end side of the cylindrical portion,
The barrier is erected inside the cylindrical portion and interposed between the outlet of the nozzle and the bottomed portion;
The gas circuit breaker according to claim 1. A first cylindrical portion surrounding the nozzle outlet at one end and having the other end open;
A cup-shaped second tubular portion that surrounds the first tubular portion and has a bottomed portion facing the opening of the first tubular portion;
The exhaust passage is
The inside of the first tubular portion;
Communicating with the opening of the first cylindrical portion, and an interior defined by an outer peripheral surface of the first cylindrical portion and an inner peripheral surface of the second cylindrical portion;
Formed with
The reflection portion is the bottomed portion of the second cylindrical portion;
The barrier is erected inside the first cylindrical portion and interposed between the outlet of the nozzle and the bottomed portion;
The gas circuit breaker according to claim 1. A flow guide is provided between the barrier and the outlet side of the nozzle,
The flow guide is continuously expanded from the outlet side of the nozzle until it is equal to or larger than the diameter of the barrier,
The gas circuit breaker according to any one of claims 1 to 4.

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