Zero-flashover cover and low-voltage electric appliance

Abstract

The utility model relates to the technical field of electrical equipment, and discloses a zero-flashover cover and a low-voltage electric appliance. The zero flashover cover comprises an outer cover and an inner cover, the inner cover is arranged in the outer cover, a first space is defined by the inner cover, a second space is formed between the inner cover and the outer cover, a communicating area is arranged on the inner cover, at least one communicating hole communicating the first space with the second space is formed in the communicating area, and a pressure relief area is arranged on the outer cover. The pressure relief area comprises at least one pressure relief hole communicating the second space with the outside, and the communicating area and the pressure relief area are arranged in a staggered mode. The zero-flashover cover can reliably stop and adsorb charged particles generated in the breaking process of electrical equipment, and prevents air discharged when a low-voltage electrical appliance is broken from causing interphase breakdown of copper bars of a complete cabinet.

Description

Technical Field

[0001] This utility model relates to the field of electrical equipment technology, and in particular to a zero-arc cover and a low-voltage electrical appliance. Background Technology

[0002] Frame-type circuit breakers / disconnecting switches are commonly used low-voltage electrical appliances in power systems. Taking disconnecting switches as an example... Figures 1-3 An exploded view of the disconnector switch is provided, as shown below. Figures 1-3 As shown, the disconnecting switch includes a disconnecting switch body 10', an arc-extinguishing chamber 20', and a zero-arc fly-out cover 30'. The arc-extinguishing chamber 20' is connected to the disconnecting switch body 10' and is used to quickly extinguish the electric arc generated when the contacts break. The zero-arc fly-out cover 30' is installed at the outlet of the arc-extinguishing chamber 20' to block charged particles generated during the disconnecting process, thereby achieving zero-arc fly-out of the disconnecting switch. Since the electric arc generated during the disconnecting process causes the air to expand due to heat, and the air pressure increases sharply in a short time, a pressure relief hole 31' is also provided on the zero-arc fly-out cover 30'. The air discharged from the arc-extinguishing chamber 20' enters the zero-arc fly-out cover 30' and is directly discharged from the pressure relief hole 31'.

[0003] Based on the existing structure, some charged particles remain in the air after it is discharged from the zero-arc shroud. However, as the power density of the switchgear increases, the voltage level of the circuit breaker / disconnector increases, and the structure of the switchgear becomes more compact, the air discharged from the zero-arc shroud with some charged particles reduces the dielectric properties of the air and poses a risk of phase-to-phase breakdown of the copper busbars in the switchgear.

[0004] Therefore, there is an urgent need for a zero-arc flyback shield and low-voltage electrical appliances to solve the above-mentioned technical problems. Utility Model Content

[0005] One objective of this invention is to provide a zero-arc fly-through cover that can reliably block and adsorb charged particles generated during the disconnection process of electrical equipment, thereby preventing the air discharged during the disconnection of low-voltage electrical equipment from causing interphase breakdown of the copper busbars in the switchgear.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A zero-arc flyback cover includes an outer cover and an inner cover. The inner cover is disposed inside the outer cover and forms a first space. A second space is formed between the inner cover and the outer cover. The inner cover has a connecting area with at least one connecting hole connecting the first space and the second space. The outer cover has a pressure relief area with at least one pressure relief hole connecting the second space and the outside. The connecting area and the pressure relief area are offset from each other.

[0008] As an alternative, the inner cover includes a labyrinth structure located within the second space and between the connecting area and the pressure relief area, wherein air entering the second space passes through the labyrinth structure and is discharged from the pressure relief hole.

[0009] As an alternative, the inner cover includes a first cover body that encloses the first space, and the maze structure includes a plurality of partitions spaced apart on the outside of the first cover body, with airflow channels formed between adjacent partitions.

[0010] As an alternative, a partition is also provided in the second space, at least part of which is opposite to the exit of the maze structure. The two sides of the partition are connected, and the maze structure and the pressure relief zone are located on the two sides of the partition, respectively.

[0011] As an alternative, the inner cover includes a first sidewall, the communicating area is disposed on the first sidewall, the outer cover includes a second sidewall, the pressure relief area is disposed on the second sidewall, and the first sidewall and the second sidewall are disposed at an angle.

[0012] As an alternative, a partition is provided in the second space, at least part of which is opposite to the pressure relief area. The two sides of the partition are connected, and the connecting area and the pressure relief area are located on the two sides of the partition, respectively.

[0013] As an alternative, the inner cover further includes a third sidewall, which is connected to the first sidewall and is arranged at an angle, and the third sidewall is at least partially opposite to the partition.

[0014] As an alternative, a metal baffle is provided in the second space, and the metal baffle is provided with multiple through holes, through which air is discharged from the pressure relief hole after passing through the metal baffle.

[0015] As an optional solution, the zero-arc flyback shield includes at least two inner shields, which divide the outer shield into a corresponding number of independent second spaces. Each first space communicates with one second space, and each second space is provided with a pressure relief zone; or

[0016] The zero-arc flyback cover includes at least two inner covers, each of which is disposed within the outer cover and forms a second space with the outer cover; at least two second spaces are in communication with the second space.

[0017] The zero-arc shield includes at least two outer shields and a corresponding number of inner shields, with each outer shield being disposed within one of the outer shields.

[0018] Another objective of this invention is to provide a low-voltage electrical appliance that, by employing the aforementioned zero-arc shield, can completely eliminate or significantly reduce the concentration of charged particles emitted during the disconnection process, thereby preventing phase-to-phase breakdown of the copper busbars in nearby equipment cabinets.

[0019] To achieve this objective, the present invention adopts the following technical solution:

[0020] Low-voltage electrical appliances include an electrical body and the aforementioned zero-arc cover, wherein the electrical body is a circuit breaker body or a disconnecting switch body.

[0021] The beneficial effects of this utility model are:

[0022] This utility model's zero-arc shroud includes an outer shroud and an inner shroud. The inner shroud is located inside the outer shroud, thus forming two relatively independent first spaces and second spaces. The first spaces and second spaces are connected by a connecting hole in the connecting area. When air carrying charged particles is discharged from the arc-extinguishing chamber of the low-voltage electrical appliance, it first enters the first space. The air meanders in the first space and makes full contact with the side wall of the first space, thus eliminating some of the charged particles. Then, the air enters the second space through the connecting hole. Since the connecting area and the pressure relief area are staggered, the air will also meander in the second space and make full contact with the outer wall of the inner shroud and the inner wall of the outer shroud, thereby further eliminating charged particles. This ensures that the charged particles in the air finally discharged from the pressure relief hole are completely eliminated or have a very low concentration, thereby avoiding phase-to-phase breakdown of the copper busbars of the complete cabinet caused by the discharged air.

[0023] The low-voltage electrical appliance of this invention, by adopting the aforementioned zero-arc shield, can completely eliminate or greatly reduce the concentration of charged particles emitted during the disconnection process, thereby preventing phase-to-phase breakdown of the copper busbars in nearby equipment cabinets. Attached Figure Description

[0024] Figure 1 This is an exploded view of the disconnector provided by existing technology;

[0025] Figure 2 This is a structural schematic diagram of a zero-arc shield provided by existing technology;

[0026] Figure 3 This is a schematic diagram of the air flow path discharged when a disconnecting switch interrupts current, provided by existing technology.

[0027] Figure 4 This is an exploded view of the disconnecting switch provided in a specific embodiment of this utility model;

[0028] Figure 5 This is an exploded structural diagram of the zero arc flash cover provided in a specific embodiment of the present invention;

[0029] Figure 6This is a schematic diagram of the air flow path discharged by the disconnecting switch when interrupting current, provided in a specific embodiment of this utility model.

[0030] Figure 7 This is a schematic diagram of the structure of the inner cover provided in a specific embodiment of this utility model.

[0031] In the picture:

[0032] 10′, Disconnecting switch body; 20′, Arc extinguishing chamber; 30′, Zero-arc cover; 31′, Pressure relief hole;

[0033] 100. Zero-arc shield; 200. Main body of disconnecting switch; 300. Arc extinguishing chamber;

[0034] 10. Outer cover; 11. Second cover body; 111. Pressure relief area; 1111. Pressure relief hole; 112. Second side wall; 12. Partition;

[0035] 20. Inner cover; 21. First cover body; 211. Communicating area; 2111. Communicating hole; 212. First side wall; 213. Third side wall; 22. Maze structure; 221. Partition; 23. Connecting plate;

[0036] 30. First Space;

[0037] 40. Second Space. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not the entire structure.

[0039] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0040] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0041] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0042] This embodiment provides a zero-arc flash enclosure and a low-voltage electrical appliance, wherein the low-voltage electrical appliance can be a circuit breaker or a disconnecting switch. The low-voltage electrical appliance includes an electrical body, an arc-extinguishing chamber 300, and a zero-arc flash enclosure 100. Taking a disconnecting switch as an example, as... Figure 4 As shown, the main electrical component is the disconnector switch body 200. In other embodiments, the low-voltage electrical component can be a circuit breaker, in which case the main electrical component is the circuit breaker body. In this embodiment, the arc-extinguishing chamber 300 is connected to the disconnector switch body 200, and the zero-flying arc shield 100 is installed at the outlet of the arc-extinguishing chamber 300. When the disconnector switch body 200 interrupts current, it generates an electric arc and charged particles. The arc-extinguishing chamber 300 is used to quickly extinguish the electric arc, protect the contacts and other components of the disconnector switch body 200 from damage by the electric arc, and also ensure the reliable and safe operation of the power system. Under the action of the electric arc, the air inside the arc-extinguishing chamber 300 is heated and expands, and the air pressure increases sharply in a short time. After passing through the zero-flying arc shield 100, it is discharged. The zero-flying arc shield 100 can block and adsorb charged particles in the air, preventing the discharged air from causing inter-phase breakdown of the copper busbars of other electrical equipment in the equipment cabinet.

[0043] like Figures 4-6As shown, the zero-arc shield 100 includes an outer shield 10 and an inner shield 20. The inner shield 20 is disposed inside the outer shield 10 and forms a first space 30. A second space 40 is formed between the inner shield 20 and the outer shield 10. A connecting area 211 is provided on the inner shield 20. The connecting area 211 has at least one connecting hole 2111 connecting the first space 30 and the second space 40. A pressure relief area 111 is provided on the outer shield 10. The pressure relief area 111 includes at least one pressure relief hole 1111 connecting the second space 40 and the outside. The connecting area 211 and the pressure relief area 111 are staggered.

[0044] After the disconnecting switch body 200 interrupts the current, when the air carrying charged particles is discharged from the arc-extinguishing chamber 300, it will first enter the first space 30. The air will meander in the first space 30 and make full contact with the side wall of the first space 30, thus eliminating some of the charged particles. Then the air will enter the second space 40 through the connecting hole 2111. Since the connecting area 211 and the pressure relief area 111 are staggered, the air will also meander in the second space 40 and make full contact with the outer wall of the inner cover 20 and the inner wall of the outer cover 10, thereby further eliminating charged particles. This ensures that the charged particles in the air discharged from the pressure relief hole 1111 are completely eliminated or have a very low concentration, thereby avoiding phase-to-phase breakdown of the copper busbars of the switchgear caused by the discharged air.

[0045] In this embodiment, both the inner cover 20 and the outer cover 10 are made of insulating material, such as plastic. Specifically, the inner cover 20 includes a first cover body 21, which is constructed as a box-shaped component with an open lower side and forms a first space 30. The outer cover 10 includes a second cover body 11, which is also constructed as a box-shaped component with an open lower side and is used to fix it to the disconnector switch body 200. After the inner cover 20 is placed inside the outer cover 30, a second space 40 is formed between the first cover body 21 and the second cover body 11. The cross-sectional size of the second cover body 11 is larger than that of the first inner cover 20, and the height of the second cover body 11 is greater than that of the first inner cover 20, so that the entire inner cover 20 can be completely inserted into the second cover body 11, and the second space 40 is formed between the outer wall of the first cover body 21 and the inner wall of the second cover body 11. The opening of the first cover body 21 is opposite to the outlet of the arc-extinguishing chamber 300 of the disconnecting switch, and the opening of the second inner cover body 20 (the part not covered by the inner cover 20) is offset from the outlet of the arc-extinguishing chamber 300, thereby ensuring that the air discharged from the arc-extinguishing chamber 300 must pass through the first space 30 and then enter the second space 40 through the connecting hole 2111.

[0046] In some embodiments, the zero-arc flashover shield 100 includes at least two inner shields 20, both of which are disposed within the outer shield 10. The at least two inner shields 20 divide the outer shield 10 into a corresponding number of independent second spaces 40. Each first space 30 communicates with one second space 40, and each second space 40 is provided with a pressure relief zone 111. That is, the zero-arc flashover shield 100 as a whole includes multiple sets of first spaces 30 and second spaces 40. Charged particles generated by the contact breakage of each pole of the low-voltage electrical appliance are eliminated through a corresponding set of first spaces 30 and second spaces 40. In this embodiment, as... Figures 4-6 As shown, the disconnecting switch is a DC disconnecting switch, which includes two poles. Correspondingly, the zero-arc shield 100 includes two inner shields 20. After the two inner shields 20 are installed into the outer shield 10, they form two independent second spaces 40. The first space 30 formed by each inner shield 20 is connected to one of the second spaces 40. The two sets of first spaces 30 and second spaces 40 respectively shield and attract charged particles generated by the contact break of the two poles of the DC disconnecting switch. In other embodiments, the number of inner shields 20 can be set according to the number of poles of the low-voltage electrical appliance. In this embodiment, as shown... Figure 6 and Figure 7 As shown, the inner cover 20 also includes a connecting plate 23, which is connected to the outside of the first cover body 21. After the inner cover 20 is installed inside the outer cover 10, the connecting plate 23 abuts against the inner wall of the outer cover 10, thereby forming at least two independent second spaces 40 inside the outer cover 10. In this embodiment, both inner covers 20 are provided with connecting plates 23, and the two connecting plates 23 are fitted together. In other embodiments, only one inner cover 20 may be provided with a connecting plate 23.

[0047] In some embodiments, the zero-arc shield 100 includes at least two inner shields 20, both of which are disposed inside the outer shield 10. Only one second space 40 is formed within the outer shield 10, and each second space 40 is connected to the other. In this embodiment, the number of inner shields 20 can be set according to the number of poles of the low-voltage electrical appliance. Air containing charged particles generated by the breaking of each pole contact enters a corresponding first space 30, and the air in each first space 30 enters the second space 40 and is then discharged.

[0048] In some embodiments, the zero-arc shield 100 includes at least two outer shields 10 and a corresponding number of inner shields 20, with each outer shield 10 disposed within one outer shield 10. In this embodiment, the number of inner shields 20 and outer shields 10 can be set according to the number of poles of the low-voltage electrical appliance, and the air containing charged particles generated by the breaking of each pole contact enters a first space 30 and a second space 40 respectively for the elimination of charged particles.

[0049] In some embodiments, the zero-arc shield 100 includes only an inner shield 20 and an outer shield 10, and the charged particles generated by the breakage of the contacts of two-pole or multi-pole low-voltage electrical appliances are eliminated by sharing the inner shield 20 and the outer shield 10.

[0050] In this embodiment, as Figure 5 and Figure 6 As shown, the first cover body 21 includes a first sidewall 212, and a connecting area 211 is disposed on the first sidewall 212. The second cover body 11 includes a second sidewall 112, and a pressure relief area 111 is disposed on the second sidewall 112. The first sidewall 212 and the second sidewall 112 are arranged at an angle. This arrangement ensures that the air discharged from the connecting hole 2111 must make at least one bend before it can be discharged from the pressure relief hole 1111, increasing the airflow path in the second space 40 and facilitating the sidewalls of the second space 40 to effectively block and absorb charged particles in the air.

[0051] In this embodiment, as Figure 6 As shown, the first sidewall 212 and the second sidewall 112 are arranged perpendicularly, with the first sidewall 212 being the top plate of the first cover body 21 and the second sidewall 112 being the side plate of the second cover body 11. The connecting area 211 on the first sidewall 212 is located at the end of the first sidewall 212 away from the second sidewall 112, thereby maximizing the airflow range and time within the second space 40 and improving the effect of blocking and adsorbing charged particles. The inner cover 20 also includes a third sidewall 213, which is connected to the first sidewall 212 and is positioned opposite and spaced apart from the second sidewall 112. This allows air entering the second space 40 to flow not only above the first sidewall 212 but also between the second sidewall 112 and the third sidewall 213, further improving the effect of removing charged particles. In this embodiment, the outer cover 10 includes two second sidewalls 112, which are arranged opposite each other, and each second sidewall 112 is provided with a pressure relief area 111. Optionally, the two second sidewalls 112 are located on the left and right sides of the low-voltage electrical appliance, respectively.

[0052] like Figure 6 and Figure 7As shown, the inner cover 20 also includes a labyrinth structure 22, which is located within the second space 40 and between the connecting area 211 and the pressure relief area 111. Air entering the second space 40 passes through the labyrinth structure 22 and is discharged from the pressure relief hole 1111. When the airflow passes through the labyrinth structure 22, it not only continuously changes its flow direction but can also form vortices or reverse flows, thereby making more thorough contact with the sidewalls of the labyrinth structure 22 and greatly improving the effect of removing charged particles. In this embodiment, the labyrinth structure 22 is disposed on the first sidewall 212 and is located on the side of the connecting area 211 near the pressure relief area 111. In addition, the upper end of the labyrinth structure 22 abuts against the top plate of the second cover body 11, thereby ensuring that the air must pass through the labyrinth structure 22 before being discharged from the pressure relief area 111. In other embodiments, the labyrinth structure 22 may also be disposed on the third sidewall 213, or partly disposed on the first sidewall 212 and partly disposed on the second sidewall 112.

[0053] like Figure 7 As shown, the maze structure 22 includes multiple spacers 221 spaced apart on the outside of the first cover body 21, forming airflow channels between adjacent spacers 221. This arrangement allows airflow to pass through different channels as it exits from one, increasing the path and time of air movement within the second space 40, thus ensuring sufficient contact with the spacers 221 and improving the removal of charged particles. In this embodiment, the spacers 221 are columnar and uniformly distributed; in other embodiments, they may be non-uniformly distributed. Optionally, the cross-section of the spacers 221 can be triangular, hypotenuse, grid-like, linear, Tesla valve-shaped, or any other shape that increases air-material contact; no limitation is imposed here.

[0054] like Figure 6 As shown, a partition 12 is also provided in the second space 40. At least part of the partition 12 is opposite to the outlet of the maze structure 22. The two sides of the partition 12 are connected, and the maze structure 22 and the pressure relief zone 111 are located on opposite sides of the partition 12. Therefore, after passing through the maze structure 22, the air needs to bypass the partition 12 to reach the pressure relief zone 111, thereby further increasing the airflow path in the second space 40 and improving the elimination effect of the zero-arc shield 100 on charged particles in the air. In this embodiment, the partition 12 is connected to the top plate of the second shield body 11, and its lower end is higher than the lower end of the first shield body 21. Air can pass under the partition 12. In this embodiment, the partition 12 is disposed between the third side wall 213 and the second side wall 112. Therefore, the partition 12 is also opposite to the pressure relief area 111. This arrangement ensures that after the airflow passes around the front of the partition 12, it will not be discharged directly from the pressure relief hole 1111, but will need to move further along the back of the partition 12 to reach the pressure relief hole 1111, thus further increasing the air discharge path.

[0055] In summary, combining Figure 6 As shown, the air flow path within the zero-flying arc shroud 100 is roughly as follows: Air enters the first space 30 through the opening on the lower side of the first shroud body 21. After the first space 30 comes into full contact with the inner wall of the first shroud body 21, it reaches the connecting area 211 and enters the second space 40 upward through the connecting hole 2111. Then, the air is stopped by the top plate of the second shroud body 11 and changes to horizontal movement, passing through the labyrinth structure 22. Then, the air flows downward through the stop of the partition 12 between the partition 12 and the second side wall 112. Then, the air flows horizontally around the partition 12 and then turns back, finally being discharged from the pressure relief hole 1111.

[0056] Optionally, in this embodiment, the partition 12 is integrally formed with the second cover body 11. In other embodiments, the partition 12 can also be fixed to the second cover body 11 by means of bonding, fastener connection, etc.

[0057] In this embodiment, the zero-arc shield 100 also includes a metal baffle (not shown in the figure). The metal baffle is disposed within the second space 40 and has multiple through holes. Air passes through the metal baffle and is discharged from the pressure relief hole 1111. On the one hand, compared with the inner cover 20 and outer cover 10 made of insulating material, the metal baffle can absorb charged particles more efficiently, thereby ensuring that the charged particles in the air discharged from the pressure relief hole 1111 are completely eliminated or extremely low in content. On the other hand, the metal baffle is disposed within the second space 40, thereby ensuring that it has a sufficiently large distance from the arc-extinguishing chamber 300, thus preventing arc breakdown. Optionally, the metal baffle can be disposed within the labyrinth structure 22, near the partition 12, or near the pressure relief area 111; no specific limitation is made here. Optionally, the metal baffle can be fixed by means of plug-in connection, fastener connection, etc. Optionally, the metal baffle can be made of stainless steel or other metal materials; no limitation is made here.

[0058] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. For those skilled in the art, based on the concept of this utility model, there will be changes in the specific implementation methods and application scope. The content of this specification should not be construed as a limitation of this utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A zero-flying arc shield, characterized in that, The device includes an outer cover (10) and an inner cover (20). The inner cover (20) is disposed inside the outer cover (10) and the inner cover (20) encloses a first space (30). A second space (40) is formed between the inner cover (20) and the outer cover (10). The inner cover (20) is provided with a connecting area (211). The connecting area (211) has at least one connecting hole (2111) connecting the first space (30) and the second space (40). The outer cover (10) is provided with a pressure relief area (111). The pressure relief area (111) includes at least one pressure relief hole (1111) connecting the second space (40) and the outside. The connecting area (211) and the pressure relief area (111) are staggered.

2. The zero-arc flyback shield as described in claim 1, characterized in that, The inner cover (20) includes a maze structure (22) located within the second space (40) and between the connecting area (211) and the pressure relief area (111). Air entering the second space (40) passes through the maze structure (22) and is discharged from the pressure relief hole (1111).

3. The zero-arc flyback shield as described in claim 2, characterized in that, The inner cover (20) includes a first cover body (21), which encloses the first space (30). The maze structure (22) includes a plurality of partitions (221) spaced apart on the outside of the first cover body (21), and airflow channels are formed between adjacent partitions (221).

4. The zero-arc flyback shield as described in claim 2, characterized in that, The second space (40) is also provided with a partition (12), at least part of the partition (12) is opposite to the exit of the maze structure (22), the two sides of the partition (12) are connected, and the maze structure (22) and the pressure relief area (111) are respectively located on both sides of the partition (12).

5. The zero-arc flyback shield as described in claim 1, characterized in that, The inner cover (20) includes a first sidewall (212), and the connecting area (211) is disposed on the first sidewall (212). The outer cover (10) includes a second sidewall (112), and the pressure relief area (111) is disposed on the second sidewall (112). The first sidewall (212) and the second sidewall (112) are disposed at an angle.

6. The zero-arc flyback shield as described in claim 5, characterized in that, The second space (40) is provided with a partition (12), at least part of the partition (12) is opposite to the pressure relief area (111), the two sides of the partition (12) are connected, and the connecting area (211) and the pressure relief area (111) are respectively located on both sides of the partition (12).

7. The zero-arc flyback shield as described in claim 6, characterized in that, The inner cover (20) also includes a third sidewall (213), which is connected to the first sidewall (212) and is set at an angle, and the third sidewall (213) is at least partially opposite to the partition (12).

8. The zero-arc flyback shield as described in claim 1, characterized in that, A metal baffle is provided in the second space (40), and multiple through holes are provided on the metal baffle. Air passes through the metal baffle and is discharged from the pressure relief hole (1111).

9. The zero-arc flyback shield as described in any one of claims 1-8, characterized in that, The zero-arc shield includes at least two inner shields (20), which divide the outer shield (10) into a corresponding number of independent second spaces (40). Each first space (30) is connected to a second space (40), and each second space (40) is provided with a pressure relief zone (111). The zero-arc shield includes at least two inner shields (20), each inner shield (20) being disposed within the outer shield (10) and forming a second space (40) with the outer shield (10). Each of the at least two second spaces (40) is in communication with the second space (40); or The zero-arc shield includes at least two outer shields (10) and a corresponding number of inner shields (20), with each outer shield (10) disposed within one of the outer shields (10).

10. A low-voltage electrical appliance, characterized in that, It includes an electrical body and a zero-arc shield as described in any one of claims 1-9, wherein the electrical body is a circuit breaker body or a disconnector switch body (200).

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