An arc quenching system and circuit protection device

Abstract

The application provides an arc extinguishing system and a circuit protection device, and relates to the technical field of low-voltage electrical apparatuses, which comprises an upper shell and a lower shell that are relatively buckled in a first direction, a containing cavity is formed in the upper shell for containing a gas generating device and a piston, a conductive copper bar is further arranged between the upper shell and the lower shell, the conductive copper bar has a weak position corresponding to the position of the piston, a permanent magnet is arranged in the lower shell, the gas generating device drives the piston to move in the first direction to cut off the weak position to generate a fracture, the permanent magnet is located on both sides of the movement path of the piston, and the arc at the fracture is extinguished through the magnetic blow effect of the permanent magnet. The arc extinguishing effect of the permanent magnet is good, reliable breaking can be realized, the permanent magnet is arranged in the lower shell, the sealing performance is good, the service life is long, the environment is protected, and the device is suitable for various environmental conditions. The structure is relatively simple, the volume is small, and the device is suitable for small-size occasions.

Description

Technical Field

[0001] This application relates to the field of low-voltage electrical technology, specifically to an arc extinguishing system and a circuit protection device. Background Technology

[0002] A pyrofuse, commonly known as an explosive fuse or instantaneous circuit breaker, uses a high-voltage surge generated by detonating explosives to trigger a mechanical device that cuts off the circuit. It mainly consists of three modules: an excitation module, an execution module, and an arc-extinguishing module. The arc-extinguishing module is the component in existing excitation fuses used for arc extinguishing; however, current arc-extinguishing methods are ineffective and cannot reliably interrupt current, thus affecting the overall performance of the system. Utility Model Content

[0003] The purpose of this application is to provide an arc extinguishing system and a circuit protection device, which has a good arc extinguishing effect and can reliably interrupt current.

[0004] One aspect of this application provides an arc extinguishing system, including an upper housing and a lower housing that are fastened to each other along a first direction. The upper housing has a cavity for accommodating a gas generating device and a piston. A conductive copper busbar is also provided between the upper housing and the lower housing. The conductive copper busbar has a weak point corresponding to the piston position. A permanent magnet is provided in the lower housing. The gas generating device drives the piston to move along the first direction to cut off the weak point and create a break. The permanent magnet is located on both sides of the piston's movement path. Arc extinguishing at the break is achieved through the magnetic blowing effect of the permanent magnet.

[0005] Optionally, there are two permanent magnets, which are located on both sides of the piston along a second direction, the second direction being the length extension direction of the conductive copper busbar, and the second direction being perpendicular to the first direction; and / or, there are two permanent magnets, which are located on both sides of the piston along a third direction, and the third direction being perpendicular to the first direction and the second direction.

[0006] Optionally, the permanent magnet is a ring-shaped permanent magnet, which surrounds the piston's movement path.

[0007] Optionally, a middle cover is provided between the upper housing and the lower housing, and a cavity for accommodating the conductive copper busbar is formed inside the middle cover.

[0008] Optionally, a narrow slit channel is formed on the lower housing corresponding to the piston position, and a pressure relief cavity is formed on the lower housing around the narrow slit channel. The pressure relief cavity is connected to the narrow slit channel, and the permanent magnet is located outside the pressure relief cavity.

[0009] Optionally, the narrow slit channel is arranged along the second direction, and the narrow slit channel communicates with the receiving cavity of the lower housing.

[0010] Optionally, an arc-extinguishing grid is provided on the lower housing corresponding to the piston position, and the permanent magnet is used to blow the electric arc into the arc-extinguishing grid to extinguish the arc.

[0011] Optionally, the lower housing is provided with a fast-acting fuse, which is connected in parallel at both ends of the weak point of the conductive copper busbar.

[0012] Optionally, the center position of the fast-acting fuse does not coincide with the center position of the weak point of the conductive copper busbar.

[0013] In another aspect of this application, a circuit protection device is provided, including: the arc extinguishing system described above and a multi-source triggering circuit, wherein the multi-source triggering circuit is used to trigger the gas generating device.

[0014] The arc-extinguishing system and circuit protection device provided in this application embodiment, under normal operation, allow current to flow through the conductive copper busbar. When the circuit needs to be cut off, a gas generator produces high-pressure gas, which pushes the piston to move in a first direction and cuts off the weak point on the lower conductive copper busbar. At this time, an arc is generated at the break, which can be extinguished by the magnetic blowing action of the permanent magnet. By setting a permanent magnet, the arc-extinguishing effect is good when using the magnetic blowing action of the permanent magnet to extinguish the arc, and reliable disconnection can be achieved. In addition, the permanent magnet is set in the lower housing, which has good sealing performance, long service life, and is environmentally friendly, suitable for various environmental conditions. Moreover, the structure is relatively simple and the size is small, which is conducive to use in small-size applications. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the initial position structure of the piston in the arc extinguishing system provided in an embodiment of this application;

[0017] Figure 2 This is a schematic diagram of the final position structure of the piston in the arc extinguishing system provided in the embodiments of this application;

[0018] Figure 3 This is one of the partial structural diagrams of the arc extinguishing system provided in the embodiments of this application;

[0019] Figure 4 yes Figure 3 One of the schematic diagrams of the cross-sectional structure along the AA direction;

[0020] Figure 5 yes Figure 4 Schematic diagram of the cross-sectional structure along the B1-B1 direction;

[0021] Figure 6 yes Figure 3 Schematic diagram of the cross-sectional structure along the AA direction (Part 2);

[0022] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure along the B2-B2 direction;

[0023] Figure 8 yes Figure 3 Schematic diagram of the cross-sectional structure along the AA direction (Part 3);

[0024] Figure 9 yes Figure 8 Schematic diagram of the cross-sectional structure along line B3-B3;

[0025] Figure 10 yes Figure 3 Schematic diagram of the cross-sectional structure along the AA direction (Part 4);

[0026] Figure 11 yes Figure 10 Schematic diagram of the cross-sectional structure along the B4-B4 direction;

[0027] Figure 12 This is one of the partial structural schematic diagrams of the arc extinguishing system provided in the embodiments of this application;

[0028] Figure 13 This is the second partial structural schematic diagram of the arc extinguishing system provided in the embodiments of this application;

[0029] Figure 14 yes Figure 13 Schematic diagram of the cross-sectional structure along the B5-B5 direction;

[0030] Figure 15 This is the second schematic diagram of the partial structure of the arc extinguishing system provided in the embodiments of this application;

[0031] Figure 16 yes Figure 15 Schematic diagram of the cross-sectional structure along the CC direction;

[0032] Figure 17 yes Figure 16 Schematic diagram of the cross-sectional structure along the DD direction;

[0033] Figure 18 It is one of the circuit diagrams for multi-source triggering;

[0034] Figure 19 This is the second circuit diagram of a multi-source triggering circuit.

[0035] Icons: 1-Top cover; 2-Upper housing; 3-Middle cover; 4-Conductive copper busbar; 41-Weak point; 5-Lower housing; 6-Lower cover; 7-Gas generator; 8-Piston; 9-Permanent magnet; 11-Narrow slit channel; 12-Fuse chamber; 13-Fast fuse; 14-Arc extinguishing grid; 20-Receiving cavity; 20a-Lower chamber; 31-Signal fuse; 32-Transformer; 33-TVS transient voltage suppressor diode; 34-Varistor; 35-Diode; 36-Current limiting resistor; 37-External trigger port; F1-First direction; F2-Second direction; F3-Third direction. Detailed Implementation

[0036] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0037] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, 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 application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0038] It should also be noted that, unless otherwise explicitly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0039] Please refer to Figure 1 , Figure 2 As shown, this application provides an arc extinguishing system, including: an upper shell 2 and a lower shell 5 that are fastened to each other along a first direction F1. The upper shell 2 has a receiving cavity 20 for accommodating a gas generating device 7 and a piston 8. A conductive copper busbar 4 is also provided between the upper shell 2 and the lower shell 5. The conductive copper busbar 4 has a weak point 41 corresponding to the position of the piston 8, so as to facilitate cutting. A permanent magnet 9 is provided in the lower shell 5. The gas generating device 7 drives the piston 8 to move along the first direction F1 in the receiving cavity 20 to cut the weak point 41 and generate an arc at the fracture. The permanent magnet 9 is located on both sides of the movement path of the piston 8. The arc is extinguished at the fracture by the magnetic blowing effect of the permanent magnet 9.

[0040] The upper housing 2 and the lower housing 5 are fastened together along the first direction F1. A receiving cavity 20 is formed inside the upper housing 2. A gas generating device 7 and a piston 8 are sequentially arranged in the receiving cavity 20 along the first direction F1. The gas generating device 7 is used to drive the piston 8 to move along the first direction F1 toward the weak point 41 of the conductive copper busbar 4. The lower housing 5 forms a lower chamber 20a. The receiving cavity 20 of the upper housing 2 and the lower chamber 20a of the lower housing 5 are separated by the conductive copper busbar 4. When the piston 8 moves along the first direction F1, the weak point 41 is cut off, and the receiving cavity 20 and the lower chamber 20a are connected. The piston 8 can extend into the lower chamber 20a of the lower housing 5.

[0041] A conductive copper busbar 4 is sandwiched between the upper housing 2 and the lower housing 5. The conductive copper busbar 4 is arranged along a second direction F2 that is perpendicular to the first direction F1, and in the second direction F2, that is, the length extension direction of the conductive copper busbar 4, both ends of the conductive copper busbar 4 extend out of the upper housing 2 and the lower housing 5.

[0042] Specifically, a middle cover 3 is provided between the upper shell 2 and the lower shell 5, and a cavity for accommodating the conductive copper busbar 4 is formed inside the middle cover 3.

[0043] In addition, along the first direction F1, the upper housing 2 is provided with an upper cover 1, and a cavity is formed between the upper cover 1 and the upper housing 2 to accommodate circuit boards and other devices; the bottom of the lower housing 5 is provided with a lower cover 6, which can strengthen the structural rigidity of the lower housing 5 and improve the stability of the overall structure.

[0044] During normal operation, current flows through the conductive copper busbar 4; when the circuit needs to be cut off, the gas generator 7 generates high-pressure gas, which pushes the piston 8 to move along the first direction F1 and cuts off the weak point 41 on the lower conductive copper busbar 4. At this time, an electric arc is generated at the break, which can be extinguished by the magnetic blow-out action of the permanent magnet 9. Figure 2 In the middle, after the weak point 41 is cut off, the material of the weak point 41 falls into the lower chamber 20a.

[0045] The principle of arc extinguishing by permanent magnet 9 is as follows: when the excitation signal is transmitted to the ignition device, the ignition device is triggered, and the gas generating device 7 instantly generates high-pressure gas to push the piston 8 to move along the first direction F1, cutting off the weak point 41 of the conductive copper busbar 4. At this time, an electric arc is generated at the break, and the arc is extinguished under the magnetic blowing action of permanent magnet 9.

[0046] The arc extinguishing system provided in this application embodiment has a good arc extinguishing effect and can achieve reliable disconnection when the permanent magnet 9 is set and the magnetic blowing action of the permanent magnet 9 is used to extinguish the arc. In addition, the permanent magnet 9 is set in the lower housing 5, which has good sealing performance, long service life, and is environmentally friendly and suitable for various environmental conditions. Moreover, the structure is relatively simple and the size is small, which is conducive to use in small-size applications.

[0047] In some embodiments, there are two permanent magnets 9, which are located on both sides of the piston 8 along the second direction F2, and the second direction F2 is perpendicular to the first direction F1. Alternatively, there are two permanent magnets 9, which are located on both sides of the piston 8 along the third direction F3, and the third direction F3 is perpendicular to both the first direction F1 and the second direction F2.

[0048] like Figures 3-5 As shown, the two permanent magnets 9 can be located on both sides of the piston 8 along the second direction F2, or as shown in the diagram. Figure 6 , Figure 7 As shown, two permanent magnets 9 are positioned on both sides of the piston 8 along the third direction F3 to partially surround the permanent magnets 9. This ensures that when the piston 8 cuts the weak point 41 of the conductive copper busbar 4 along the first direction F1, the two permanent magnets 9 are symmetrically positioned on both sides of the piston 8. In this way, the permanent magnets 9 can be used to extinguish the arc at the break point and prevent the arc from escaping.

[0049] In some embodiments, such as Figure 8 , Figure 9 As shown, there are four permanent magnets 9, two of which are located on both sides of the piston 8 along the second direction F2, and the other two are located on both sides of the piston 8 along the third direction F3.

[0050] Figure 8 On the plane formed by the second direction F2 and the third direction F3, four permanent magnets 9 are located on the four sides of the piston 8, semi-enclosing the piston 8. Compared with the arrangement of two permanent magnets 9, four permanent magnets 9 completely surround the piston 8, resulting in a better arc extinguishing effect.

[0051] In some embodiments, such as Figure 10 , Figure 11 As shown, the permanent magnet 9 is a ring-shaped permanent magnet, which surrounds the movement path of the piston 8. The ring-shaped permanent magnet 9 is an integral structure that surrounds the movement path of the piston 8, completely enclosing it, thus further improving the arc-extinguishing effect of the permanent magnet 9 on the broken arc.

[0052] The aforementioned method uses a permanent magnet 9 to extinguish the arc. When the short-circuit breaking current through the conductive copper busbar 4 is small, the permanent magnet 9 absorbs the arc between the breaks, thus extinguishing the arc and achieving reliable breaking from zero current to a small short-circuit current.

[0053] When the short-circuit breaking current through the conductive copper busbar 4 is large, the permanent magnet 9 can absorb part of the arc and play the role of magnetic blow to lengthen the arc and increase the arc voltage. At this time, based on the arc extinguishing of the permanent magnet 9, the recovery of the dielectric strength can be enhanced by combining the narrow slit channel 11 or the arc extinguishing grid plate 14, or the parallel fast fuse 13, etc., to enhance the arc extinguishing capability of the product and achieve reliable breaking of large short-circuit current.

[0054] Specifically, such as Figure 12 As shown, a narrow slit channel 11 is also formed on the lower housing 5 corresponding to the position of the piston 8. For example, the narrow slit channel 11 is arranged along the second direction F2 and communicates with the lower chamber 20a. A pressure relief cavity is also formed on the lower housing 5 around the narrow slit channel 11. The pressure relief cavity communicates with the narrow slit channel 11, and the permanent magnet 9 is located outside the pressure relief cavity.

[0055] Both the narrow slit channel 11 and the pressure relief chamber are located within the lower housing 5. The narrow slit channel 11 corresponds to the piston 8. The piston 8 moves along the first direction F1, cutting off the weak point 41 of the conductive copper busbar 4 and inserting into the narrow slit channel 11. The electric arc is elongated within the narrow slit channel 11. Simultaneously, the piston 8 and the inner wall of the lower housing 5 generate gas under the ablation of the electric arc. This creates a high-temperature and high-pressure arc-extinguishing environment within the narrow slit channel 11, thereby accelerating the arc extinguishing speed. After arc extinguishing, the high-temperature and high-pressure gas generated during arc extinguishing can enter the pressure relief chamber through the narrow slit channel 11, accelerating the recovery of the medium strength and improving the overall arc extinguishing effect.

[0056] Refer to Figure 13 , Figure 14 As shown, the lower housing 5 is provided with a fuse chamber 12, and a fast fuse 13 is provided in the fuse chamber 12. The fast fuse 13 can be connected in parallel to both ends of the weak position 41 of the conductive copper busbar 4 by means of clips or screws.

[0057] When the piston 8 moves to cut off the weak point 41, due to the large short-circuit breaking current, the magnetic blow-out effect of the permanent magnet 9 can extinguish part of the arc; the extinguishing of the other part of the arc is undertaken by the fast fuse 13. The arc at the break point can be transferred to the fast fuse 13. As the current accumulates on the fast fuse 13, it melts the fast fuse 13, which can also play the role of extinguishing the arc.

[0058] Furthermore, along the first direction F1, the center position of the fast-acting fuse 13 does not coincide with the center position of the weak point 41 of the conductive copper busbar 4. In other words, the fast-acting fuse 13 is offset from the center of the weak point 41 for isolation. This avoids the energy generated during arc extinguishing from impacting the lower housing 5 and the upper housing 2 when the short-circuit breaking current is large, thus ensuring the overall stability of the arc extinguishing system.

[0059] It can also be like Figures 15-17 As shown, an arc-extinguishing grid 14 is provided on the lower housing 5 corresponding to the position of the piston 8, and the arc is extinguished in conjunction with the arc-extinguishing grid 14. When the piston 8 moves along the first direction F1 to cut off the weak point 41, the arc is partially extinguished under the magnetic blowing action of the permanent magnet 9. At this time, the magnetic blowing action of the permanent magnet 9 can also blow the remaining arc into the arc-extinguishing chamber formed by the arc-extinguishing grid 14, where the arc is extinguished.

[0060] The above three embodiments illustrate that, under the arc extinguishing action of the permanent magnet 9, the arc extinguishing is further enhanced by the narrow slit channel 11, the fast fuse 13, and the arc extinguishing grid 14, thereby improving the arc extinguishing speed and effect and increasing the reliability of arc extinguishing.

[0061] Based on the above embodiments, a signal fuse 31 can also be connected in series on the conductive copper busbar 4, corresponding to a multi-source triggering circuit diagram disclosed, such as... Figure 18 , Figure 19 As shown.

[0062] This circuit diagram can trigger the gas generator 7. The circuit diagram includes a load circuit, an internal trigger circuit, and an external trigger circuit, which are electrically connected to each other.

[0063] The load circuit includes a load, a signal fuse 31, and a conductive copper busbar 4, which are connected in series.

[0064] The internal triggering circuit includes a transformer 32 and a TVS transient voltage suppressor diode 33. The input terminal of the transformer 32 is connected in parallel across the signal fuse 31, and the TVS transient voltage suppressor diode 33 is connected in parallel across the output terminal of the transformer 32.

[0065] The external trigger circuit includes an external trigger port 37, a current-limiting resistor 36, a diode 35, a varistor 34, and a gas generator 7 (igniter); the external trigger port 37, the current-limiting resistor 36, the diode 35, and the varistor 34 are connected in parallel across the gas generator 7, while the current-limiting resistor 36 and the diode 35 are connected in series.

[0066] The electronic components such as transformer 32, TVS transient voltage suppressor diode 33, varistor 34, and diode 35 are used to prevent the system power supply, i.e., the external trigger source, from being broken down by the internal trigger source, thus protecting the components of the external system circuit.

[0067] Based on this, the embodiments of this application also disclose a circuit protection device, including an arc extinguishing system as described above and a multi-source triggering circuit. The multi-source triggering circuit is used to trigger the gas generating device 7, and the circuit diagram of the multi-source triggering circuit is shown below. Figure 18 , Figure 19 As shown. This circuit protection device has the same structure and beneficial effects as the arc-extinguishing system in the foregoing embodiments. The structure and beneficial effects of the arc-extinguishing system have been described in detail in the foregoing embodiments and will not be repeated here.

[0068] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An arc quenching system, characterized in that, include: An upper housing (2) and a lower housing (5) are fastened together along a first direction (F1). The upper housing (2) has a cavity (20) for accommodating a gas generator (7) and a piston (8). A conductive copper busbar (4) is also provided between the upper housing (2) and the lower housing (5). The conductive copper busbar (4) has a weak point (41) corresponding to the position of the piston (8). A permanent magnet (9) is provided in the lower housing (5). The gas generator (7) drives the piston (8) to move along the first direction (F1) to cut off the weak point (41) and create a break. The permanent magnet (9) is located on both sides of the movement path of the piston (8). The arc is extinguished at the break by the magnetic blowing action of the permanent magnet (9).

2. The quenching system of claim 1, wherein, There are two permanent magnets (9), and the two permanent magnets (9) are located on both sides of the piston (8) along the second direction (F2). The second direction (F2) is the length extension direction of the conductive copper busbar (4). The second direction (F2) is perpendicular to the first direction (F1). Or, there are two permanent magnets (9), and the two permanent magnets (9) are located on both sides of the piston (8) along the third direction (F3). The third direction (F3) is perpendicular to the first direction (F1) and the second direction (F2).

3. The quenching system of claim 1, wherein, The permanent magnet (9) is a ring-shaped permanent magnet (9) that surrounds the movement path of the piston (8).

4. The quenching system of claim 1, wherein, A middle cover (3) is provided between the upper housing (2) and the lower housing (5), and a cavity for accommodating the conductive copper busbar (4) is formed inside the middle cover (3).

5. The quenching system according to any one of claims 1 to 4, characterized in that A narrow slit channel (11) is formed on the lower housing (5) corresponding to the position of the piston (8). A pressure relief cavity is also formed on the lower housing (5) around the narrow slit channel (11). The pressure relief cavity is connected to the narrow slit channel (11). The permanent magnet (9) is located outside the pressure relief cavity.

6. The quenching system of claim 5, wherein, The narrow slit channel (11) is arranged along the second direction (F2), and the narrow slit channel (11) is connected to the receiving cavity (20) of the lower housing (5).

7. The quenching system according to any one of claims 1 to 4, characterized in that An arc-extinguishing grid plate (14) is provided on the lower housing (5) corresponding to the position of the piston (8), and the permanent magnet (9) is used to blow the electric arc into the arc-extinguishing grid plate (14) to extinguish the arc.

8. The quenching system according to any one of claims 1 to 4, characterized in that The lower housing (5) is provided with a fast fuse (13), which is connected in parallel at both ends of the weak point (41) of the conductive copper busbar (4).

9. The quenching system of claim 8, wherein, The center position of the fast fuse (13) does not coincide with the center position of the weak point (41) of the conductive copper busbar (4).

10. A circuit protection device, characterized by It includes the arc extinguishing system as described in any one of claims 1 to 9 and the multi-source triggering circuit, wherein the multi-source triggering circuit is used to trigger the gas generating device.

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