Gas circuit breaker

Abstract

The present invention provides a gas circuit breaker, which prevents the reduction of the insulation performance of the gas and improves the cutting performance by cooling the high-temperature gas flowing into the hot compressed air chamber and blowing it to the arc. The gas circuit breaker comprises: a movable main contact (5); a movable arc contact (2); a compressed air cylinder (8) having the movable main contact (5); a hollow rod (6) arranged inside the compressed air cylinder (8) and having the movable arc contact, and in which the insulating gas flows; a hot compressed air chamber (10) surrounded by the compressed air cylinder and the hollow rod; an insulating cover (13) arranged on the hollow rod and covering the movable arc contact; an insulating nozzle (11) arranged on the compressed air cylinder; and a cylindrical guide (16) extending axially. The guide is arranged in the hot compressed air chamber, located on the outer peripheral side of the hollow rod, and connected to the insulating nozzle. The space between the guide and the hollow rod is connected to the space between the insulating nozzle and the insulating cover, and is the flow path of the insulating gas.

Description

Technical Field

[0001] The present invention relates to a gas circuit breaker, and more particularly to a gas circuit breaker for extinguishing an arc by blowing an insulating gas to an arc generated between contacts when a current is interrupted. Background Art

[0002] In recent years, the power system has been moving towards higher voltage and higher current, and in order to obtain the required interruption performance, the gas circuit breaker has been moving towards a larger capacity. In addition, in order to reduce costs, the miniaturization of the gas circuit breaker is also moving forward through the optimization of the structure of the interruption part, the exhaust part, the shielding part, etc. However, in the compressed gas type gas circuit breaker, which obtains the pressure of the gas blown during arc extinguishing only by mechanical compression, there is a limit to the miniaturization of the device. As the operating energy of the operator increases, the development of a hot compressed gas type gas circuit breaker is moving forward, which uses the arc heat generated when the current is interrupted to expand the gas, and blows the gas under this pressure to extinguish the arc.

[0003] The hot-compression gas type gas circuit breaker blows high-pressure insulating gas compressed in a mechanical pressure chamber and a hot-compression gas chamber to the arc generated between the fixed arc contact and the movable arc contact to extinguish the arc. In the hot-compression gas type gas circuit breaker, since the pressure of the gas is formed in the hot-compression gas chamber by utilizing the arc heat, the operating force required for the operator can be reduced, and the operator can be miniaturized.

[0004] Patent document 1 describes an example of a conventional hot-gas type gas circuit breaker. In the gas circuit breaker described in patent document 1, a hot-gas chamber is provided in series with a mechanical air chamber, a partition member is provided in the hot-gas chamber to radially divide the chamber, a switching valve is provided between the arc space and the hot-gas chamber as an airflow control member, and a movable valve is provided between the hot-gas chamber and the mechanical air chamber. When a large current is cut off, the switching valve is used to blow the high-temperature and high-pressure arc-extinguishing gas from the arc space from the outer peripheral space of the partition member through the inner peripheral space to the arc. When a small or medium current is cut off, the arc-extinguishing gas from the mechanical air chamber is guided only to the inner peripheral space of the partition member and blown to the arc.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2012-079601

[0008] Problems to be solved by the invention

[0009] In a thermocompressor type gas circuit breaker, the gas pressure is formed in the thermocompressor chamber by arc heat. Therefore, the temperature of the gas blown toward the arc generated when the current is cut off becomes high and becomes hot gas, which reduces the insulation performance of the gas and may reduce the cutting performance. In particular, if the current to be cut off is large, the arc heat increases, so the gas temperature becomes higher and sufficient cutting performance may not be obtained.

[0010] The gas circuit breaker described in Patent Document 1 is provided with a partition component, a switching valve, and a movable valve that radially divide the interior of a hot-pressed gas chamber, thereby improving the arc extinguishing performance when cutting off large currents and when cutting off small and medium currents. However, since the partition component of the gas circuit breaker described in Patent Document 1 is arranged in the hot-pressed gas chamber, the volume of the hot-pressed gas chamber, that is, the volume of the gas used for arc extinguishing is reduced, and the cutting performance may be reduced. In particular, when cutting off small and medium currents, gas is blown toward the arc only from the inner peripheral space of the partition component, so the volume of the gas used for arc extinguishing may be halved. In addition, since the gas circuit breaker described in Patent Document 1 is provided with a partition component, a switching valve, and a movable valve, the number of parts increases, and the cost may increase.

[0011] Thus, in conventional gas circuit breakers, if the arc heat is used to form gas pressure in the hot pressure chamber, the temperature of the gas blown toward the arc becomes high, which reduces the insulation performance of the gas, or the volume of the gas is reduced, which may reduce the cutting performance. In addition, if new operating parts such as a switching valve and a movable valve are provided, there is a problem that the cost may increase. Summary of the invention

[0012] An object of the present invention is to provide a gas circuit breaker that prevents the insulation performance of the gas from being reduced and improves the interruption performance by cooling the high-temperature gas flowing into a hot pressure gas chamber and blowing it toward the arc.

[0013] Solutions to Solve Problems

[0014] The gas circuit breaker of the present invention is provided with a cylindrical gas storage tank filled with insulating gas, and the gas storage tank is provided with: a movable main contact, which moves in the axial direction and separates from the fixed main contact to cut off the current; a movable arc contact, which generates an arc between the movable arc contact and the fixed arc contact when the current is cut off; a compressed air cylinder, which has the movable main contact at one end; a hollow rod, which is arranged inside the compressed air cylinder and has the movable arc contact at one end, and the insulating gas flows inside the hollow rod; a hot compressed air chamber, which is surrounded by the compressed air cylinder and the hollow rod; an insulating cover, which is arranged at one end of the hollow rod and covers the movable arc contact; an insulating nozzle, which is arranged at one end of the compressed air cylinder; and a flow guide, which is a cylindrical component extending in the axial direction. The guide is arranged in the hot compressed air chamber, located on the outer peripheral side of the hollow rod, and one end of the guide is connected to the insulating nozzle. The space between the guide and the hollow rod is connected to the space between the insulating nozzle and the insulating cover, which is the flow path of the insulating gas.

[0015] Effects of the Invention

[0016] According to the present invention, a gas circuit breaker can be provided which prevents the insulation performance of the gas from being reduced and improves the interruption performance by cooling the high-temperature gas flowing into the hot plenum and blowing it toward the arc. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view schematically showing the structure of a conventional gas circuit breaker in a closed state.

[0018] Figure 2 It is a cross-sectional view schematically showing the structure of a conventional gas circuit breaker at the time of disconnection.

[0019] Figure 3 It is a cross-sectional view showing a schematic structure of the gas circuit breaker according to the first embodiment of the present invention at the time of disconnection.

[0020] Figure 4 This is a diagram showing the air flow from the arc space into the hot pressure chamber when a small or medium current is cut off.

[0021] Figure 5 It is a cross-sectional view showing a schematic structure of the gas circuit breaker according to the second embodiment of the present invention at the time of disconnection.

[0022] Figure 6 It is along Figure 5 A cross-sectional view of the guide member observed along the cutting line AA.

[0023] Figure 7This is a diagram showing a flow guide having a tapered hole.

[0024] Figure 8 It is a cross-sectional view showing a schematic structure of the gas circuit breaker according to the third embodiment of the present invention at the time of disconnection.

[0025] Fig. 9 It is a cross-sectional view showing a schematic structure of another gas circuit breaker according to the third embodiment of the present invention at the time of disconnection.

[0026] Fig.10 It is a cross-sectional view showing a schematic structure of the gas circuit breaker according to the fourth embodiment of the present invention at the time of disconnection.

[0027] Description of Reference Numerals

[0028] 1 gas storage tank, 2 movable arc contact, 3 fixed arc contact, 4 fixed main contact, 5 movable main contact, 6 hollow rod, 7 air compression piston, 8 air compression cylinder, 9 mechanical air compression chamber, 10 hot air compression chamber, 11 insulating nozzle, 12 shielding part, 13 insulating cover, 14 check valve, 15 connecting hole, 16 guide part, 17 hole, 19 operator, 30 arc, 31 hot gas, 32 air flow, 33 cold gas, 34 arc space, 35 stopper. DETAILED DESCRIPTION

[0029] The following is a description of a gas circuit breaker according to an embodiment of the present invention using the accompanying drawings. In the drawings used in this specification, the same or corresponding components are marked with the same reference numerals, and sometimes repeated descriptions of these components are omitted. It should be noted that the embodiments shown below are merely examples of implementation of the present invention, and the content of the present invention is not limited to the following forms.

[0030] [Example 1]

[0031] First, a conventional thermocompressor type gas circuit breaker will be described.

[0032] Figure 1 It is a cross-sectional view schematically showing the structure of a conventional gas circuit breaker in a closed state (energized state). Figure 2 This is a cross-sectional view showing the schematic structure of a conventional gas circuit breaker during cutting. Figure 2 In FIG. 1 , the upper half shows the gas flow 32 when the gas flows from the arc space 34 (space where the arc 30 is generated) into the hot compressed air chamber 10, and the lower half shows the gas flow 32 when the gas is blown from the hot compressed air chamber 10 to the arc 30. Figure 2 In the figure, the gas storage tank 1 is omitted.

[0033] The gas circuit breaker includes: a cylindrical gas tank 1 filled with insulating gas, a movable arc contact 2, a fixed arc contact 3, a movable main contact 5, and a fixed main contact 4. The movable arc contact 2, the fixed arc contact 3, the movable main contact 5, and the fixed main contact 4 are accommodated in the gas tank 1. As the insulating gas, SF6 can be used, for example. It should be noted that the insulating gas is not limited to SF6, and other insulating gases such as dry air and nitrogen can also be used.

[0034] Next, the direction of the axis of the gas storage tank 1 ( Figure 1 The left and right directions of the moving arc contact 2 and the moving main contact 5 are called "axial directions", the directions perpendicular to the axial directions are called "radial directions", and the directions around the axial directions are called "circumferential directions". Figure 1 The right direction of the moving arc contact 2 and the moving main contact 5 is called the "cut-off direction". When the gas circuit breaker performs a closing action and changes from the cut-off state to the on state, the direction in which the movable arc contact 2 and the movable main contact 5 move ( Figure 1 The left direction of the switch is referred to as the “on direction”. Insulating gas is also referred to as “gas” for short.

[0035] The movable arc contact 2 and the fixed arc contact 3 face each other in the axial direction and can move in the axial direction. When the current is cut off, an arc is generated between the movable arc contact 2 and the fixed arc contact 3. The movable arc contact 2 is located closer to the cutting direction ( Figure 1 ), is electrically connected to the fixed arc contact 3 in the on state, and is physically separated from the fixed arc contact 3 in the off state.

[0036] The movable main contact 5 faces the fixed main contact 4 in the axial direction and can move in the axial direction to perform an opening action to cut off the current and a closing action to connect the current. The movable main contact 5 is located closer to the fixed main contact 4 in the cutting direction ( Figure 1 The movable main contact 5 and the fixed main contact 4 constitute a main contact.

[0037] The gas circuit breaker further includes a pressure cylinder 8 , a hollow rod 6 , a pressure piston 7 , a mechanical pressure chamber 9 , a thermal pressure chamber 10 , an insulating cover 13 , an insulating nozzle 11 , a shield 12 , and an operator 19 .

[0038] The compressed air cylinder 8 is located on the outer peripheral side (radially outer side) of the movable arc contact 2, and is configured to have a central axis shared with the movable arc contact 2. The compressed air cylinder 8 has a movable main contact 5 at one end in the connection direction, and accommodates a hollow rod 6. It should be noted that the inner peripheral surface of the compressed air cylinder 8 is parallel to the axial direction.

[0039] The hollow rod 6 is arranged inside the air cylinder 8 in a manner having a central axis shared with the air cylinder 8. The hollow rod 6 has a movable arc contact 2 at one end in the connection direction. The interior of the hollow rod 6 is hollow, and insulating gas flows inside. It should be noted that the outer peripheral surface of the hollow rod 6 is parallel to the axial direction.

[0040] The gas piston 7 is supported by a mounting seat provided on the inner peripheral surface of the gas tank 1 , is located inside the gas cylinder 8 , and moves in a space formed between the gas cylinder 8 and the hollow rod 6 .

[0041] The mechanical air compression chamber 9 is surrounded by the air compression cylinder 8 , the hollow rod 6 and the air compression piston 7 .

[0042] The hot compressed air chamber 10 is surrounded by the compressed air cylinder 8 and the hollow rod 6, and is configured to allow the insulating gas to flow in or out, and has a fixed volume. The hot compressed air chamber 10 is provided with a check valve 14, is adjacent to the mechanical compressed air chamber 9 in the axial direction, and is connected to the mechanical compressed air chamber 9 through a connecting hole 15. The connecting hole 15 is provided in the wall separating the hot compressed air chamber 10 from the mechanical compressed air chamber 9, and is opened and closed by the check valve 14. That is, the communication between the hot compressed air chamber 10 and the mechanical compressed air chamber 9 is controlled by the check valve 14.

[0043] The check valve 14 is provided on the outer peripheral surface of the hollow rod 6 inside the hot compressed air chamber 10, and moves in the axial direction by the pressure difference between the hot compressed air chamber 10 and the mechanical compressed air chamber 9. If the pressure inside the hot compressed air chamber 10 is lower than the pressure inside the mechanical compressed air chamber 9, the check valve 14 moves in the connection direction to open the communication hole 15, so that the hot compressed air chamber 10 and the mechanical compressed air chamber 9 are connected. If the pressure inside the hot compressed air chamber 10 is higher than the pressure inside the mechanical compressed air chamber 9, the check valve 14 moves in the cut-off direction to close the communication hole 15, so that the hot compressed air chamber 10 and the mechanical compressed air chamber 9 are not connected.

[0044] The insulating cover 13 is provided at one end portion of the hollow rod 6 in the connection direction, and covers the movable arc contact 2 .

[0045] The insulating nozzle 11 is located on the outer peripheral side of the insulating cover 13 and is provided at one end of the connecting direction of the compressed air cylinder 8. The space between the insulating nozzle 11 and the insulating cover 13 communicates with the hot compressed air chamber 10 and serves as a flow path for the gas.

[0046] The shield 12 covers the fixed arc contact 3 and the fixed main contact 4 .

[0047] The operator 19 can move the insulating nozzle 11 , the air cylinder 8 , the hollow rod 6 , the movable arc contact 2 , the movable main contact 5 , and the like in the cutting direction.

[0048] Gas circuit breaker in the on state ( Figure 1 ) under the condition that the movable arc contact 2 contacts with the fixed arc contact 3, and the movable main contact 5 contacts with the fixed main contact 4.

[0049] When a short circuit occurs in the power system, the gas circuit breaker receives a disconnection command and performs a disconnection operation. The operator 19 moves the hollow rod 6 and the air cylinder 8 in the disconnection direction, and moves the movable arc contact 2 and the movable main contact 5 in the disconnection direction, thereby performing a disconnection operation. The movable arc contact 2 is physically separated from the fixed arc contact 3, and the movable main contact 5 is physically separated from the fixed main contact 4 ( Figure 2 After the movable main contact 5 is separated from the fixed main contact 4, current also flows between the movable arc contact 2 and the fixed arc contact 3, generating an arc 30 ( Figure 2 The gas circuit breaker blows high-pressure insulating gas toward the generated arc 30 to extinguish the arc.

[0050] During the cut-off, when the movable arc contact 2 and the movable main contact 5 move, the air cylinder 8 moves relative to the air piston 7, whereby the air piston 7 compresses the insulating gas inside the mechanical air chamber 9. In more detail, the driving force of the operator 19 is transmitted to the air cylinder 8 via the insulating rod (not shown) and the hollow rod 6 connected to the operator, and the air cylinder 8 moves, whereby the insulating gas inside the mechanical air chamber 9 is compressed by the air piston 7. If the check valve 14 opens the connecting hole 15, the compressed insulating gas flows from the mechanical air chamber 9 into the hot air chamber 10 through the connecting hole 15, flows in the space between the insulating nozzle 11 and the insulating cover 13, and blows toward the arc 30, thereby extinguishing the arc 30 ( Figure 2 (lower part of the figure).

[0051] In the thermocompressor type gas circuit breaker, pressure is generated by taking hot gas 31, which is a gas heated by arc heat, into the thermocompressor chamber 10. Therefore, the interruption principle of the thermocompressor type gas circuit breaker differs depending on the magnitude of the interrupted current.

[0052] When a large current (e.g., a current near a peak value) is cut off, the energy of the arc 30 is large, and the pressure of the gas in the arc space 34 (the space where the arc 30 is generated) is higher than the pressure of the gas in the hot pressure chamber 10. The hot gas 31 flows into the hot pressure chamber 10 through the space between the insulating nozzle 11 and the insulating cover 13 ( Figure 2 The pressure inside the hot compressed air chamber 10 rises significantly due to arc heat and is greater than the pressure inside the mechanical compressed air chamber 9. Therefore, the check valve 14 closes the connecting hole 15, so that the hot compressed air chamber 10 and the mechanical compressed air chamber 9 are not connected. The insulating gas compressed under the pressure inside the hot compressed air chamber 10 is blown from the hot compressed air chamber 10 to the arc 30, and the arc 30 is extinguished.

[0053] When the current to be cut off is relatively small or medium, even if the pressure inside the hot compressed air chamber 10 rises due to arc heat, it is still lower than the pressure inside the mechanical compressed air chamber 9. Therefore, the check valve 14 opens the connecting hole 15 to connect the hot compressed air chamber 10 with the mechanical compressed air chamber 9. The insulating gas compressed in the mechanical compressed air chamber 9 flows from the mechanical compressed air chamber 9 to the hot compressed air chamber 10 through the connecting hole 15, and is blown from the hot compressed air chamber 10 to the arc 30, so that the arc 30 is extinguished.

[0054] When the gas flows into the hot pressure chamber 10 ( Figure 2 The hot gas 31 flows from the arc space 34 to the hot pressure chamber 10 through the space between the insulating nozzle 11 and the insulating cover 13. The hot gas 31 flowing into the hot pressure chamber 10 flows deep into the hot pressure chamber 10 in the cutting direction ( Figure 2 However, there is cold air 33 (gas of lower temperature than the hot air 31) in the hot compressed air chamber 10, and the cold air 33 is pushed into the depth of the cut-off direction of the hot compressed air chamber 10 by the hot air 31. Therefore, the hot air 31 does not spread to the entire hot compressed air chamber 10, does not fully mix with the cold air 33, and does not efficiently exchange heat with the cold air 33.

[0055] In particular, when the current to be cut is relatively small or medium, the energy of the arc 30 is small, so the gas flow rate is not fast, and the hot gas 31 does not reach the depth of the hot pressure gas chamber 10 in the cutting direction ( Figure 2 31 is not cooled by the hot air 31, and is retained near the connecting portion (entrance of the hot air 31) of the hot air chamber 10 that is connected to the arc space 34. Therefore, the hot air 31 cannot be fully cooled by mixing with the cold air 33 inside the hot air chamber 10, and the temperature is maintained at a high level.

[0056] When the energy of the arc 30 decreases, the pressure in the arc space 34 decreases, and the pressure in the hot pressure chamber 10 becomes higher than the pressure in the arc space 34, the insulating gas starts to be blown from the hot pressure chamber 10 to the arc 30. When the insulating gas is blown to the arc 30 ( Figure 2 ), hot gas 31 which is not sufficiently cooled and exists near the connecting portion of the hot pressure gas chamber 10 connected to the arc space 34 is blown toward the arc 30. Therefore, the insulating performance of the gas used for arc extinguishing is reduced, and it may not be possible to obtain sufficient cutting performance.

[0057] A gas circuit breaker according to a first embodiment of the present invention will be described. Figure 1 and Figure 2 Description of the common structure of the conventional gas circuit breaker shown is omitted, and the structure different from the conventional gas circuit breaker is mainly described.

[0058] Figure 3This is a cross-sectional view showing the schematic structure of the gas circuit breaker of this embodiment when it is cut off. Figure 3 In, with Figure 2 Similarly, the upper half shows the airflow 32 when gas flows from the arc space 34 (the space where the arc 30 is generated) into the hot compressed air chamber 10, and the lower half shows the airflow 32 when gas is blown from the hot compressed air chamber 10 toward the arc 30, and the illustration of the gas tank 1 is omitted.

[0059] The gas circuit breaker of this embodiment is provided with a flow guide 16 which is a cylindrical component extending in the axial direction. The flow guide 16 is provided in the hot compressed air chamber 10, is located on the outer peripheral side (radially outer side) of the hollow rod 6, and one end portion is connected to the insulating nozzle 11. The flow guide 16 is a component provided in the hot compressed air chamber 10 in such a manner that the insulating nozzle 11 extends in the axial direction. The space between the flow guide 16 and the hollow rod 6 is connected to the space between the insulating nozzle 11 and the insulating cover 13, and forms a flow path of the gas that connects the hot compressed air chamber 10 with the arc space 34.

[0060] When the gas flows from the arc space 34 into the hot pressure chamber 10 ( Figure 3 The guide member 16 and the hollow rod 6 are formed to guide the hot gas 31 to the depth of the hot pressure chamber 10 in the cutting direction ( Figure 3 In this embodiment, the guide member 16 extends parallel to the axial direction, that is, parallel to the inner circumference of the compression cylinder 8, and when the hot gas 31 flows into the hot compression chamber 10, the hot gas 31 flows parallel to the axial direction.

[0061] The guide 16 may be made of the same material as the insulating nozzle 11. The insulating nozzle 11 may be made of a composite material in which an inorganic filler is added to a resin having lower heat resistance than a fluororesin, for example, a fluororesin mixed with boron nitride (BN) powder. The guide 16 may be manufactured integrally with the insulating nozzle 11, or may be manufactured separately from the insulating nozzle 11 and then provided on the insulating nozzle 11.

[0062] The gas circuit breaker of this embodiment is provided with a flow guide 16. When the gas flows into the hot pressure gas chamber 10 ( Figure 3 The hot gas 31 can be guided to the depth of the hot pressure chamber 10 in the cutting direction ( Figure 3 The guide 16 guides the hot gas 31 to the depth of the cut-off direction of the hot compressed air chamber 10, thereby fully mixing and cooling the hot gas 31 with the cold air 33 inside the hot compressed air chamber 10, thereby preventing the insulation performance of the gas from being reduced. In particular, when a small or medium current with a slow gas flow rate is cut off, the hot gas 31 can reach the depth of the cut-off direction of the hot compressed air chamber 10 through the flow path formed by the guide 16, and will not be retained near the connection portion of the hot compressed air chamber 10 that is connected to the arc space 34.

[0063] The other end of the guide 16 (the end on the axially opposite side to the end connected to the insulating nozzle 11) is preferably located at a position farther from the insulating nozzle 11 in the axial direction than the axial center of the hot plenum 10. That is, the other end of the guide 16 is preferably located deeper in the cutting direction of the hot plenum 10 than the axial center of the hot plenum 10 ( Figure 3 In this structure, when the hot air 31 flows into the hot compressed air chamber 10, the hot air 31 can be more effectively guided to the depth of the cutting direction of the hot compressed air chamber 10.

[0064] Figure 4 Yes means Figure 3 The diagram of a portion of the upper half of FIG. 1 is a diagram showing the air flow 32 flowing from the arc space 34 into the hot pressure chamber 10 when a small or medium current is cut off.

[0065] When the medium and small currents are cut off, since the pressure inside the hot compressed air chamber 10 is lower than the pressure inside the mechanical compressed air chamber 9, the check valve 14 opens the connecting hole 15 to connect the hot compressed air chamber 10 with the mechanical compressed air chamber 9. The insulating gas compressed in the mechanical compressed air chamber 9 flows from the mechanical compressed air chamber 9 to the hot compressed air chamber 10 through the connecting hole 15, and forms an airflow 32 in the space between the guide 16 and the compression cylinder 8 inside the hot compressed air chamber 10. Through this airflow 32, the hot gas 31 flowing in the flow path between the guide 16 and the hollow rod 6 can be cooled in the entire internal space of the hot compressed air chamber 10.

[0066] The gas circuit breaker of this embodiment is equipped with a flow guide 16, which can fully mix and cool the hot gas 31 flowing into the hot compressed air chamber 10 and the cold air 33 inside the hot compressed air chamber 10, and blow the cooled gas toward the arc 30, thereby preventing the insulation performance of the gas from being reduced and improving the cutting performance.

[0067] In addition, the flow path area of ​​the gas flowing from the hot pressure gas chamber 10 to the arc space 34 (the cross-sectional area of ​​the flow path perpendicular to the flow direction of the gas) is preferably such that it becomes smaller from upstream to downstream in the direction of gas flow from the hot pressure gas chamber 10 to the arc space 34 (the flow direction of the gas when blowing gas toward the arc 30).

[0068] like Figure 4 As shown, the flow area of ​​the flow path C1 formed by the insulating nozzle 11 and the insulating cover 13 and opening in the arc space 34 is set to S1, the flow area of ​​the flow path C2 formed by the insulating nozzle 11 and the insulating cover 13 and located upstream of the flow path C1 is set to S2, and the flow area of ​​the flow path C3 formed by the guide member 16 and the hollow rod 6 and located upstream of the flow path C2 and opening in the hot compression gas chamber 10 is set to S3.

[0069] When the flow path area S3 is larger than the flow path area S2 and the flow path area S2 is larger than the flow path area S1, when blowing gas toward the arc 30, the flow path area gradually decreases as the gas flows, so there is no reduction in the gas flow rate due to the expansion of the gas. Therefore, the gas can be blown from the hot pressure gas chamber 10 toward the arc 30 without stagnating the gas flow, and the cutting performance of the gas circuit breaker can be improved.

[0070] [Example 2]

[0071] A gas circuit breaker according to a second embodiment of the present invention will be described. Hereinafter, the gas circuit breaker according to the present embodiment will be described mainly with respect to the structure that is different from the gas circuit breaker according to the first embodiment.

[0072] Figure 5 This is a cross-sectional view showing the schematic structure of the gas circuit breaker of this embodiment when it is cut off. Figure 5 In, with Figure 3 Similarly, the upper half shows the airflow 32 when gas flows from the arc space 34 (the space where the arc 30 is generated) into the hot compressed air chamber 10, and the lower half shows the airflow 32 when gas is blown from the hot compressed air chamber 10 toward the arc 30, and the illustration of the gas tank 1 is omitted.

[0073] The flow guide 16 of the gas circuit breaker of this embodiment has a hole 17 penetrating in the radial direction. The hole 17 is provided on the side of the flow guide 16 to connect the inside of the flow guide 16 with the outside. The flow guide 16 may have one hole 17 in the circumferential direction, but preferably has a plurality of holes 17 in the circumferential direction. In addition, the flow guide 16 may also have a plurality of holes 17 in the axial direction. The number of holes 17 is arbitrary.

[0074] Figure 6 It is along Figure 5 sectional view of the air guide member 16 observed along the cutting line AA. Figure 5 and Figure 6 The flow guide element 16 shown has four holes 17 in the circumferential direction.

[0075] like Figure 5 As shown in the upper half of the figure, when the gas flows from the arc space 34 into the hot pressure chamber 10, the gas flows in the flow path between the insulating nozzle 11 and the insulating cover 13 and the flow path between the guide 16 and the hollow rod 6, so that the axial velocity vector becomes larger. Therefore, the hot gas 31 reaches the depth of the hot pressure chamber 10 in the cutting direction ( Figure 5 on the right side) without passing through hole 17.

[0076] use Figure 5 The lower half of the figure illustrates the gas flow 32 when the gas is blown from the hot pressure gas chamber 10 to the arc 30, that is, when it is cut off.

[0077] When cutting off small and medium currents, the gas flowing from the mechanical compressed air chamber 9 to the hot compressed air chamber 10 flows through the flow path between the flow guide 16 and the hollow rod 6 and the flow path between the insulating nozzle 11 and the insulating cover 13 through the hole 17 and blows toward the arc 30. The hot gas 31 reaching the hot compressed air chamber 10 circulates inside the hot compressed air chamber 10 through the air flow from the mechanical compressed air chamber 9 through the hole 17, thereby being cooled more effectively.

[0078] When cutting off the large current, the check valve 14 is closed, and there is no airflow from the mechanical compression chamber 9 to the hot compression chamber 10, but the cold air 33 inside the hot compression chamber 10 is guided to the space between the guide member 16 and the compression cylinder 8, and blown toward the arc 30 through the hole 17.

[0079] As described above, the gas circuit breaker of the present embodiment can prevent the insulation performance of the gas from being degraded, and can improve the interruption performance.

[0080] like Figure 5 As shown in the figure in the lower half of the figure, the flow path area of ​​the gas in the hole 17 of the flow guide 16 is set to S4. The flow path area S4 is preferably larger than the flow path area S3 described in Example 1. When the flow path area S4 is larger than the flow path area S3, the flow rate of the cold air 33 blown to the arc 30 through the hole 17 can be increased, and the cutting performance of the gas circuit breaker can be improved. Therefore, when the flow path area S4 is larger than the flow path area S3, the flow path area S3 is larger than the flow path area S2, and the flow path area S2 is larger than the flow path area S1, the cutting performance of the gas circuit breaker can be more effectively improved.

[0081] The hole 17 of the flow guide 16 is preferably shaped such that the flow path area S4 decreases from the outer side to the inner side in the radial direction.

[0082] Figure 7 is with Figure 5 The figure corresponding to a part of the lower half of the figure is a figure showing a guide member 16 having a tapered hole 17. Figure 7 As shown, the flow guide 16 includes a hole 17 whose flow path area S4 decreases from the outside to the inside in the radial direction. Figure 7 In FIG. 1 , a tapered hole 17 is shown as an example. If the hole 17 of the flow guide 16 has such a shape, gas can be blown from the hot compressed gas chamber 10 toward the arc 30 without stagnating the air flow flowing in the hole 17, and the interruption performance of the gas circuit breaker can be improved.

[0083] [Example 3]

[0084] A gas circuit breaker according to a third embodiment of the present invention will be described. Hereinafter, the gas circuit breaker according to the present embodiment will be described mainly with respect to the structure that is different from the gas circuit breaker according to the first embodiment.

[0085] Figure 8This is a cross-sectional view showing the schematic structure of the gas circuit breaker of this embodiment when it is cut off. Figure 8 In, with Figure 3 Similarly, the upper half shows the airflow 32 when gas flows from the arc space 34 (the space where the arc 30 is generated) into the hot compressed air chamber 10, and the lower half shows the airflow 32 when gas is blown from the hot compressed air chamber 10 toward the arc 30, and the illustration of the gas tank 1 is omitted.

[0086] In the first and second embodiments, the guide member 16 extends parallel to the axial direction (i.e., parallel to the inner circumference of the compression cylinder 8). When the hot gas 31 flows from the arc space 34 into the hot compression chamber 10 ( Figure 3 , 5 The hot gas 31 is made to flow parallel to the axial direction and is guided to the depth of the hot pressure chamber 10 in the cutting direction ( Figure 3 , 5 on the right side of the screen).

[0087] In this embodiment, the guide member 16 extends axially and tilted toward the radial outside. When the hot gas 31 flows into the hot pressure chamber 10 ( Figure 8 The hot gas 31 is caused to flow in a manner inclined relative to the axial direction and directed radially outward. That is, the flow path of the gas formed by the guide member 16 and the hollow rod 6 is configured so that the hot gas 31 flowing into the hot pressure gas chamber 10 flows toward the check valve 14. The hot gas 31 flowing into the hot pressure gas chamber 10 flows toward the check valve 14 through the guide member 16 and is guided to the depth of the hot pressure gas chamber 10 in the cut-off direction ( Figure 8 on the right side of the screen).

[0088] A stopper 35 is provided on the outer peripheral surface of the hollow rod 6. The stopper 35 is a component that stops the movement of the check valve 14 when the check valve 14 moves in the connection direction to open the communication hole 15. Since the guide member 16 extends toward the oblique radial outer side at an angle relative to the axial direction, the hot gas 31 flowing into the hot pressure gas chamber 10 flows toward the check valve 14 without being blocked by the stopper 35.

[0089] Fig. 9 It is a cross-sectional view schematically showing the structure of another gas circuit breaker of the present embodiment at the time of disconnection. Fig. 9 The gas circuit breaker shown has Figure 8 The structure of the gas circuit breaker shown in FIG. 1 is the same as that of the hollow rod 6. Figure 8 The gas circuit breakers shown are different.

[0090] exist Fig. 9 In the gas circuit breaker shown in FIG. 1 , the outer circumference of the hollow rod 6 extends axially and tilts radially outwards, similarly to the flow guide 16. Since the outer circumference of the hollow rod 6 extends radially outwards and tilts radially with respect to the axial direction, Fig. 9The gas circuit breaker shown is also Figure 8 Similarly to the gas circuit breaker shown, the gas flow path formed by the guide member 16 and the hollow rod 6 is configured so that the hot gas 31 flowing into the hot pressure gas chamber 10 flows toward the check valve 14. It should be noted that Fig. 9 The illustrated gas circuit breaker does not include the stopper 35 for stopping the operation of the check valve 14 , but the hollow rod 6 stops the operation of the check valve 14 .

[0091] When the current to be cut off is relatively large, since the pressure inside the thermal compression chamber 10 is greater than the pressure inside the mechanical compression chamber 9, the check valve 14 moves in the cut-off direction to close the connecting hole 15, so that the thermal compression chamber 10 and the mechanical compression chamber 9 are not connected. If the action of the check valve 14 is delayed, the pressure in the thermal compression chamber 10 is transmitted to the mechanical compression chamber 9, and the pressure reaction force increases due to the decrease in the pressure of the thermal compression chamber 10 and the increase in the pressure of the mechanical compression chamber 9, and the speed of the cut-off action may be reduced.

[0092] In the gas circuit breaker of the present embodiment, the gas flow path formed by the flow guide 16 and the hollow rod 6 is configured so that the hot gas 31 flowing into the hot pressure chamber 10 flows toward the check valve 14. Therefore, the check valve 14 is subjected to the dynamic pressure of the flow of the hot gas 31 and can move faster in the cut-off direction to close the connecting hole 15. When the hot gas 31 flows into the hot pressure chamber 10, the gas circuit breaker of the present embodiment can move the check valve 14 in the cut-off direction faster, and can prevent the pressure of the hot pressure chamber 10 from decreasing, the pressure of the mechanical pressure chamber 9 from increasing, and the reduction of the cut-off speed.

[0093] [Example 4]

[0094] A gas circuit breaker according to a fourth embodiment of the present invention will be described. Hereinafter, the gas circuit breaker according to the present embodiment will be described mainly with respect to the structure that is different from the gas circuit breaker according to the third embodiment.

[0095] Fig.10 This is a cross-sectional view showing the schematic structure of the gas circuit breaker of this embodiment when it is cut off. Fig.10 In, with Fig. 9 Similarly, the upper half shows the airflow 32 when gas flows from the arc space 34 (the space where the arc 30 is generated) into the hot compressed air chamber 10, and the lower half shows the airflow 32 when gas is blown from the hot compressed air chamber 10 toward the arc 30, and the illustration of the gas tank 1 is omitted.

[0096] It should be noted that the gas circuit breaker of this embodiment can also be Figure 8 As in the gas circuit breaker shown in FIG. 1 , the outer peripheral surface of the hollow rod 6 is parallel to the axial direction.

[0097] In the gas circuit breaker of the third embodiment, the flow guide 16 has a hole 17 penetrating in the radial direction, similarly to the gas circuit breaker of the second embodiment. The flow guide 16 has the hole 17, and can form the same airflow as that described in the second embodiment when cutting off. Therefore, the gas circuit breaker of the present embodiment can prevent the insulation performance of the gas from being reduced when cutting off small and medium currents and when cutting off large currents, and can improve the cutting performance.

[0098] It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications are possible. For example, the above-mentioned embodiments are embodiments described in detail in order to easily explain the present invention, and the present invention is not limited to the form that must have all the structures described. In addition, a part of the structure of a certain embodiment can be replaced with the structure of other embodiments. In addition, the structure of other embodiments can be added to the structure of a certain embodiment. In addition, for a part of the structure of each embodiment, other structures can be deleted or added or replaced.

Claims

1. A gas circuit breaker, characterized in that: The gas circuit breaker includes a cylindrical gas tank filled with insulating gas, and the gas tank includes: A movable main contact, wherein the movable main contact moves in the axial direction to separate from the fixed main contact and cut off the current; A movable arc contact, wherein an arc is generated between the movable arc contact and the fixed arc contact when the current is cut off; A pressure cylinder, wherein the pressure cylinder has the movable main contact at one end; A hollow rod, the hollow rod being arranged inside the air pressure cylinder and having the movable arc contact at one end thereof, and the insulating gas flowing inside the hollow rod; A hot compressed air chamber, which is surrounded by the compressed air cylinder and the hollow rod; An insulating cover, which is arranged at one end of the hollow rod and covers the movable arc contact; an insulating nozzle, the insulating nozzle being arranged at one end of the air compressor cylinder; and A flow guide, wherein the flow guide is a cylindrical component extending in the axial direction, The guide member is arranged in the hot pressure air chamber and is located on the outer peripheral side of the hollow rod. One end of the guide member is connected to the insulating nozzle. The space between the flow guide and the hollow rod is connected to the space between the insulating nozzle and the insulating cover, and is the flow path of the insulating gas; Wherein, the space between the flow guide and the hollow rod, i.e., the flow path area of ​​the flow path of the insulating gas, is larger than the space between the insulating nozzle and the insulating cover, i.e., the flow path area of ​​the flow path of the insulating gas; Wherein, the flow guide has a hole penetrating in the radial direction on the side surface; The flow path area of ​​the hole is larger than the flow path area of ​​the space between the flow guide and the hollow rod, ie, the flow path of the insulating gas.

2. The gas circuit breaker according to claim 1, characterized in that The other end of the guide member is located at a position farther from the insulating nozzle in the axial direction than the axial center of the hot compressed air chamber.

3. The gas circuit breaker according to claim 1, characterized in that The flow guide element extends axially while being inclined toward the radial outer side.

4. The gas circuit breaker according to claim 3, characterized in that The outer peripheral surface of the hollow rod extends axially while being inclined toward the radial outer side.

5. The gas circuit breaker according to claim 3 or 4, characterized in that: The gas circuit breaker has: a mechanical compressed air chamber, the mechanical compressed air chamber being connected to the thermal compressed air chamber through a connecting hole; and a check valve, the check valve being arranged inside the hot pressure air chamber to open and close the connecting hole, The space between the flow guide and the hollow rod, ie, the flow path of the insulating gas, is configured to allow the insulating gas to flow toward the check valve.

6. The gas circuit breaker according to claim 1, characterized in that The flow path area of ​​the hole decreases from the outer side to the inner side in the radial direction.

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