Contact arc extinguishing system

Abstract

The invention provides an arc extinguishing system. The arc extinguishing system comprises a first arc extinguishing group, a second arc extinguishing group, a third arc extinguishing group, a first end tab, a second end tab, an insulating shell, a contact group, a conducting piece and an end cover. The contact piece group is opposite to the conduction piece. And the three arc extinguishing groups are arranged in the insulating shell and are arranged behind the contact group together. And the first run-on plate is tightly attached to the conduction piece and is arranged below the first arc extinguishing group. And the second run-on plate is arranged above the third arc extinguishing group. A contact plate is arranged at one end, facing the contact group, of the second run-on plate. Magnetism increasing plates are arranged on the two sides of the contact plate, and a local magnetism increasing area is defined by the magnetism increasing plates and the contact plate. The arc extinguishing group is matched with the long contact piece of the contact group to form an arc striking structure, and when the circuit breaker is switched off, a local magnetism increasing area is constructed at the stopping position of the long contact piece of the contact group, so that the electromagnetic driving force of an arc entering the arc extinguishing group is improved. Meanwhile, staggered main cutting areas and side cutting areas are arranged in the arc extinguishing groups, group-by-group, batch and partition cutting of the arc and the cutting blades is achieved, the arc cutting difficulty is lowered, and the arc extinguishing capacity of the contact arc extinguishing system is improved.

Description

Technical Field

[0001] This invention relates to a circuit breaker, and more particularly to an arc-extinguishing system for the contacts of a circuit breaker. Background Technology

[0002] Circuit breakers are mainly used in power distribution networks to distribute electrical energy and protect lines and power equipment from faults such as overload, undervoltage, short circuit, and single-phase grounding. Under normal conditions, they can also be used for infrequent line switching. The protection of power distribution lines by circuit breakers primarily occurs when a fault such as a short circuit occurs. The mechanical system drives the movement of the circuit breaker's contact assembly, separating the contact assembly from the conducting element, thereby interrupting the fault current and implementing line protection. However, during the separation of the contact assembly from the conducting element, the fault current of the protected line is not directly interrupted. A high-temperature, high-voltage arc is generated between them, maintaining the conduction of the protected line and making it difficult to interrupt the fault current. Existing technologies mostly employ an arc-extinguishing system composed of arc-extinguishing grids, an insulating shell, contact assemblies, conducting elements, and end caps to extinguish the high-temperature, high-voltage arc during the circuit breaker's interruption of the fault current. When an arc is generated, it is attracted by the arc-extinguishing grids, enters the arc-extinguishing system, and is extinguished by cutting and cooling the grids. Whether an electric arc can be extinguished by entering the arc-extinguishing system and being cut by the grid plates depends primarily on whether the number of grid plates effectively cut by the arc is sufficient. As the number of grid plates increases, it becomes more difficult for the arc to cut them, resulting in an insufficient number of effectively cut grid plates. Even if the arc is cooled by cutting through a certain number of grid plates, it still fails to extinguish and cannot interrupt the fault current. With the gradual increase in voltage in power distribution systems in the new energy sector, the number of grid plates in circuit breaker arc-extinguishing systems is increasing, making this problem even more prominent. Summary of the Invention

[0003] The purpose of this invention is to provide an arc extinguishing system with local magnetization and multiple cutting, which solves the problem that the arc is difficult to extinguish after the number of arc extinguishing chamber grids increases.

[0004] To achieve the above objectives, this invention designs a contact arc-extinguishing system, comprising a first arc-extinguishing group, a second arc-extinguishing group, a third arc-extinguishing group, a first arc-initiating plate, a second arc-initiating plate, an insulating shell, a contact plate group, a conductive element, and an end cap. The contact plate group is opposite to the conductive element. The first, second, and third arc-extinguishing groups are housed within the insulating shell. The first, second, and third arc-extinguishing groups are positioned behind the contact plate group. An end cap is installed behind the first, second, and third arc-extinguishing groups. The first arc-initiating plate is in close contact with the conductive element and is positioned below the first arc-extinguishing group; the second arc-initiating plate is positioned above the third arc-extinguishing group. The first and third arc-extinguishing groups are composed of several auxiliary cutting plates. The second arc-extinguishing group is composed of several main cutting plates. Specifically, the second arc-initiating plate has a contact plate at one end facing the contact group. Magnetizing plates are provided on both sides of the contact plate of the second arc-initiating plate, forming a localized magnetizing area with the contact plate.

[0005] Furthermore, an extension plate is provided at one end of the second arc-initiating plate facing the third arc-extinguishing group. The extension plate is positioned above the third arc-extinguishing group. The extension plate is arranged parallel to the secondary cutting blade of the third arc-extinguishing group. A contact plate is bent out at the center of the end of the extension plate facing the contact group. Transition plates are bent out on both sides of the contact plate at the end of the extension plate facing the contact group. A magnetizing plate is bent out of the transition plate facing the contact plate. The magnetizing plate and the contact plate surround a local magnetizing area.

[0006] Furthermore, the end of the conductive element facing the contact group is a contact section. A stationary main contact and a stationary secondary contact are fixed on the side of the contact section facing the contact group. The end of the conductive element away from the contact group is a connecting section. The connecting section is arranged perpendicular to the contact section. The connecting section and the contact section are naturally connected by an inclined transition section.

[0007] Furthermore, a long contact piece is arranged in the center of the contact group. Several second contact pieces and several short contact pieces are arranged sequentially on both sides of the contact group. The long contact piece has a moving main contact and a moving auxiliary contact on the side facing the conducting element. The moving main contact is opposite to the stationary main contact. The moving auxiliary contact is opposite to the stationary auxiliary contact. The automatic auxiliary contact of the long contact piece naturally transitions towards the second arc-starting plate, extending into an arc-ignition arm. The second contact piece has a second main contact and a second auxiliary contact on the side facing the conducting element. The second main contact is opposite to the stationary main contact; the second auxiliary contact is opposite to the stationary auxiliary contact. The short contact piece has a third main contact on the side facing the conducting element. The third main contact is opposite to the stationary main contact. In the circuit breaker open state, the arc-ignition arm of the long contact piece is placed in a local magnetization zone.

[0008] Furthermore, an inclined mounting plate is provided at the end of the first arc-initiating plate facing the conductive element. The mounting plate is in contact with the transition section of the conductive element. The first arc-initiating plate bends from the mounting plate toward the contact group to form a jumper plate. The jumper plate is horizontal with the contact section on the conductive element; the jumper plate is flush with the secondary contact. A fixed arc plate is provided at the end of the first arc-initiating plate facing the first arc-extinguishing group. The fixed arc plate is positioned below the first arc-extinguishing group. The fixed arc plate is arranged parallel to the secondary cutting blade of the first arc-extinguishing group. The jumper plate and the fixed arc plate are naturally connected by an inclined connecting plate.

[0009] Furthermore, a main cutting body is provided on the side of the main cutting blade near the end cap. The main cutting blade extends naturally from the main cutting body towards the contact assembly, with a main blade wide arm and a main blade narrow arm extending naturally on both the left and right sides. On the side of the main blade wide arm facing the center line of the main cutting blade, the following components are arranged in sequence from the main cutting body towards the contact assembly: a concave edge, a cutting protrusion, a concave shape, a bevel, and an edge. On the side of the main blade narrow arm facing the center line of the main cutting blade, the following components are arranged in sequence from the main cutting body towards the contact assembly: a concave edge, a cutting protrusion, a bevel, and an edge. The concave edges of the main blade wide and narrow arms are matched to form the main cutting area of ​​the main blade, with the concave edge of the main blade wide arm closer to the center line of the main cutting blade than the concave edge of the main blade narrow arm. The main sheet's wide arm concave and narrow arm cutting convex are matched, and the main sheet's wide arm bevel and narrow arm bevel are matched, together forming the main sheet's side cutting area. The main sheet's narrow arm cutting convex is closer to the center line of the main cutting disc than the main sheet's wide arm concave, and the main sheet's wide arm bevel is closer to the center line of the main cutting disc than the main sheet's narrow arm bevel.

[0010] Furthermore, a secondary cutting body is provided on the side of the secondary cutting blade near the end cap. From the secondary cutting body towards the contact assembly, the secondary cutting blade naturally extends into a secondary wide arm and a secondary narrow arm on both the left and right sides. On the side of the secondary wide arm facing the center line of the secondary cutting blade, from the secondary cutting body towards the contact assembly, a secondary wide arm concave edge, a secondary wide arm cutting convex edge, a secondary wide arm concave edge, a secondary wide arm bevel, and a secondary wide arm edge are arranged in sequence. On the side of the secondary narrow arm facing the center line of the secondary cutting blade, from the secondary cutting body towards the contact assembly, a secondary narrow arm concave edge, a secondary narrow arm cutting convex edge, a secondary narrow arm bevel, and a secondary narrow arm edge are arranged in sequence. The concave edges of the secondary wide and narrow arms are matched to form the main cutting area of ​​the secondary blade, with the concave edge of the secondary wide arm closer to the center line of the secondary cutting blade than the concave edge of the secondary narrow arm. The concave side of the wide arm of the sub-piece and the convex side of the narrow arm of the sub-piece are matched relative to each other, and the inclined side of the wide arm of the sub-piece and the inclined side of the narrow arm of the sub-piece are matched relative to each other, together forming the side cutting area of ​​the sub-piece. The convex side of the narrow arm of the sub-piece is closer to the center line of the sub-cutting piece than the concave side of the wide arm of the sub-piece, and the inclined side of the wide arm of the sub-piece is closer to the center line of the sub-cutting piece than the inclined side of the narrow arm of the sub-piece.

[0011] Furthermore, the insulating shell has several mounting slots on its left and right sides, each corresponding to the next. On the side of the insulating shell facing the contact assembly, a first protective shell is positioned on the left and right sides near the first arc-guiding plate, a third protective shell is positioned on the left and right sides near the second arc-guiding plate, and a second protective shell is positioned on the left and right sides in the middle. The first, second, and third protective shells on the same side are naturally connected and transitioned sequentially.

[0012] Furthermore, the main cutting blade's wide arm and narrow arm are housed within the second protective shell of the insulating shell. The secondary cutting blade's wide arm and narrow arm are housed within the first and third protective shells of the insulating shell.

[0013] The technical advantages of this invention are that the second arc-initiating plate, through bending, not only forms an arc-initiating structure that matches the long contact piece of the contact group, but also, in the circuit breaker's open state, creates a local magnetization zone at the final resting position of the long contact piece of the contact group, thereby significantly enhancing the electromagnetic driving force for the arc to enter the arc-extinguishing group. Furthermore, multiple sets of arc-extinguishing groups of varying lengths with different front-to-back positions of the cutting convex and central concave sections for arc cutting are arranged within the arc-extinguishing system cavity. Staggered main cutting areas and side cutting areas are set within each arc-extinguishing group, enabling group-by-group, batch-by-batch, and zone-by-zone cutting of the arc and the cutting blade, thereby reducing the difficulty of arc cutting and improving the contact arc-extinguishing system's ability to cut and extinguish the arc. Attached Figure Description

[0014] Figure 1 This invention relates to a three-dimensional structural schematic diagram of a contact arc extinguishing system;

[0015] Figure 2 This invention relates to a schematic diagram of the structure of the second arc-initiating plate of a contact arc-extinguishing system;

[0016] Figure 3 This invention relates to a schematic diagram of the structure of a secondary cutting plate in a contact arc extinguishing system;

[0017] Figure 4 This invention relates to a schematic diagram of the structure of the main cutting plate of a contact arc extinguishing system;

[0018] Figure 5 This invention relates to a schematic diagram of the structure of the first arc-initiating plate of a contact arc-extinguishing system;

[0019] Figure 6 This invention relates to a schematic diagram of the structure of an insulating shell for a contact arc extinguishing system;

[0020] Figure 7 This invention relates to a schematic diagram of the contact assembly of a contact arc extinguishing system;

[0021] Figure 8 This invention relates to a schematic diagram of the closing position of a contact arc extinguishing system;

[0022] Figure 9 This invention relates to a schematic diagram of the opening position of a contact arc extinguishing system. Detailed Implementation

[0023] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0024] Marker explanation:

[0025] First arc-extinguishing group 1; Second arc-extinguishing group 2; Third arc-extinguishing group 3;

[0026] 10 secondary cutting discs;

[0027] Sub-piece wide arm 101; Sub-piece wide arm edge 1011; Sub-piece wide arm bevel 1012; Sub-piece wide arm concave 1013; Sub-piece wide arm cutting convex 1014; Sub-piece wide arm concave edge 1015;

[0028] Sub-piece narrow arm 102; Sub-piece narrow arm edge 1021; Sub-piece narrow arm bevel 1022; Sub-piece narrow arm cutting protrusion 1023; Sub-piece narrow arm concave edge 1024;

[0029] Sub-piece cutting body 103; Sub-piece mounting protrusion 104;

[0030] Sub-cutting blade centerline 1090; Sub-cutting blade cutting concave width 1091; Sub-cutting blade main cutting area 1092; Sub-cutting blade side cutting area 1093;

[0031] Main cutting blade 20;

[0032] Main piece wide arm 201; Main piece wide arm edge 2011; Main piece wide arm bevel 2012; Main piece wide arm concave 2013; Main piece wide arm cutting protrusion 2014; Main piece wide arm concave edge 2015;

[0033] Main piece narrow arm 202; Main piece narrow arm edge 2021; Main piece narrow arm bevel 2022; Main piece narrow arm cutting protrusion 2023; Main piece narrow arm concave edge 2024;

[0034] Main piece cutting body 203; Main piece mounting protrusion 204;

[0035] Main cutting blade centerline 2090; main blade cutting concave width 2091; main blade main cutting area 2092; main blade side cutting area 2093;

[0036] First arc-initiating plate 4;

[0037] Mounting plate 401; Jump plate 402; Connecting plate 403; Fixed arc plate 404; Fixing plate 405;

[0038] Second arc-inducing plate 5;

[0039] Contact plate 501; Transition plate 502; Extension plate 503; Magnetizing plate 504; Local magnetizing area 50;

[0040] Insulating shell 6;

[0041] First protective shell 601; Second protective shell 602; Third protective shell 603;

[0042] Mounting slot 604; positioning rib 6041; mounting hole 6042;

[0043] Contact group 7;

[0044] Long contact piece 71; Contact arm 7101; Arc-ignition arm 7102; Moving main contact 7103; Moving auxiliary contact 7104;

[0045] Second contact piece 72; Second main contact 7203; Second auxiliary contact 7204;

[0046] Short contact 73; Third main contact 7303;

[0047] End cap 8; Conductor 9;

[0048] Contact section 901; transition section 902; connecting section 903; stationary main contact 904; stationary auxiliary contact 905.

[0049] like Figure 1 As shown, the present invention provides a contact arc extinguishing system, comprising a first arc extinguishing group 1, a second arc extinguishing group 2, a third arc extinguishing group 3, a first arc-inducing plate 4, a second arc-inducing plate 5, an insulating shell 6, a contact assembly 7, a conductive element 9, and an end cap 8. The contact assembly 7 is opposite to the conductive element 9. When the contact assembly 7 is in contact with the conductive element 9, the circuit breaker is conducting; when the contact assembly 7 is separated from the conductive element 9, the circuit breaker is disengaging. The first arc extinguishing group 1, the second arc extinguishing group 2, and the third arc extinguishing group 3 are placed inside the insulating shell 6; the first arc extinguishing group 1, the second arc extinguishing group 2, and the third arc extinguishing group, together with the insulating shell 6, are placed behind the contact assembly 7. An end cap 8 is installed behind the first arc extinguishing group 1, the second arc extinguishing group 2, and the third arc extinguishing group 3. The first arc-inducing plate 4 is in close contact with the conductive element 9, and the first arc-inducing plate 4 is positioned below the first arc extinguishing group 1. The second arc-inducing plate 5 is positioned above the third arc extinguishing group 3. The second arc-extinguishing group 2 is composed of several main cutting blades 20, and the first arc-extinguishing group 1 and the third arc-extinguishing group 3 are composed of several auxiliary cutting blades 10.

[0050] The conductive element 9 has a contact section 901 at the end facing the contact group 7. A stationary main contact 904 and a stationary auxiliary contact 905 are fixed to the side of the contact section 901 facing the contact group 7. The conductive element 9 has a connecting section 903 at the end away from the contact group 7. The connecting section 903 is arranged perpendicular to the contact section 901. The connecting section 903 and the contact section 901 are naturally connected via an inclined transition section 902.

[0051] like Figure 5 As shown, the first arc-inducing plate 4 has an inclined mounting plate 401 at one end facing the conductor 9. The mounting plate 401 is in contact with the transition section 902 of the conductor 9. The first arc-inducing plate 4 bends from the mounting plate 401 toward the contact group 7 to form a jumper plate 402. The jumper plate 402 is horizontal with the contact section 901 on the conductor 9. The jumper plate 402 is flush with the secondary contact 905. The first arc-inducing plate 4 has a fixed arc plate 404 at one end facing the first arc-extinguishing group 1. The fixed arc plate 404 is below the first arc-extinguishing group 1. The fixed arc plate 404 is arranged parallel to the secondary cutting piece 10 of the first arc-extinguishing group 1. The jumper plate 402 and the fixed arc plate 404 are naturally connected by an inclined connecting plate 403. The first arc-inducing plate 4 bends from the mounting plate 401 away from the contact group 7 to form a fixing plate 405. The conductive element 9 is fixedly installed into the inner cavity of the circuit breaker housing via the first arc-guiding plate 4 fixed thereon.

[0052] like Figure 2 As shown, an extension plate 503 is provided at one end of the second arc-inducing plate 5 facing the third arc-extinguishing group 3. The extension plate 503 is positioned at the upper end of the third arc-extinguishing group 3. The extension plate 503 is arranged parallel to the secondary cutting blade 10 of the third arc-extinguishing group 3. A contact plate 501 is bent out from the center of the end of the extension plate 503 facing the contact group 7. Transition plates 502 are bent out from both sides of the contact plate 501 at the end of the extension plate 503 facing the contact group 7. A magnetizing plate 504 is bent out from the transition plate 502 facing the contact plate 501. The magnetizing plate 504 and the contact plate 501 surround a local magnetizing area 50.

[0053] like Figure 7As shown, a long contact piece 71 is arranged in the center of the contact group 7. Several second contact pieces 72 and several short contact pieces 73 are arranged sequentially on both sides of the contact group 7. The long contact piece 71 has a moving main contact 7103 and a moving auxiliary contact 7104 on the side facing the conductor 9. The moving main contact 7103 is opposite to the stationary main contact 904. The moving auxiliary contact 7104 is opposite to the stationary auxiliary contact 905. The automatic auxiliary contact 7104 of the long contact piece 71 extends naturally towards the second arc-starting plate 5, forming an arc-ignition arm 7102. When the circuit breaker is in the open state, the arc-ignition arm 7102 is located directly in front of the contact plate 501 on the second arc-starting plate 5, maintaining a distance of less than or equal to 5 mm from the contact plate 501. The second contact piece 72 has a second main contact 7203 and a second auxiliary contact 7204 on the side facing the conductor 9. The second main contact 7203 is opposite to the stationary main contact 904. The second auxiliary contact 7204 is opposite to the stationary auxiliary contact 905. A third main contact 7303 is provided on the side of the short contact piece 73 facing the conductive member 9. The third main contact 7303 is opposite to the stationary main contact 904.

[0054] like Figure 4As shown, a main cutting body 203 is provided on the side of the main cutting blade 20 near the end cap 8. The main cutting blade 20 extends naturally from the main cutting body 203 toward the contact assembly 7, with a main blade wide arm 201 and a main blade narrow arm 202 extending naturally from both sides. On the side of the main blade wide arm 201 facing the center line 2090 of the main cutting blade, from the main cutting body 203 toward the contact assembly 7, the following components are arranged in sequence: a main blade wide arm concave edge 2015, a main blade wide arm cutting protrusion 2014, a main blade wide arm concave 2013, a main blade wide arm bevel 2012, and a main blade wide arm edge 2011. On the side of the main blade narrow arm 202 facing the center line 2090 of the main cutting blade, from the main cutting body 203 toward the contact assembly 7, the following components are arranged in sequence: a main blade narrow arm concave edge 2024, a main blade narrow arm cutting protrusion 2023, a main blade narrow arm bevel 2022, and a main blade narrow arm edge 2021. The main sheet wide arm concave edge 2015 and the main sheet narrow arm concave edge 2024 are matched to form the main sheet main cutting area 2092. The main sheet wide arm concave edge 2015 is closer to the center line 2090 of the main cutting blade than the main sheet narrow arm concave edge 2024. An inward concave shape offset from the center line 2090 of the main cutting blade is formed in the main cutting area 2092 of the main cutting blade 20. The main sheet wide arm concave edge 2013 and the main sheet narrow arm cutting protrusion 2023 are matched to each other, and the main sheet wide arm chamfer 2012 and the main sheet narrow arm chamfer 2022 are matched to each other, forming the main sheet side cutting area 2093. The main sheet narrow arm cutting protrusion 2023 is closer to the center line 2090 of the main cutting blade than the main sheet wide arm concave edge 2013, and the main sheet wide arm chamfer 2012 is closer to the center line 2090 of the main cutting blade than the main sheet narrow arm chamfer 2022. Several main cutting blades 20, forming the second arc-extinguishing group 2, are arranged with adjacent main cutting blades 20 rotated 180 degrees around the center line 2090 of the main cutting blade. For this purpose, the main blade wide arm cutting protrusions 2014 of two adjacent grid blades in the main cutting area 2092 of the main blade are opposite each other, and the main blade narrow arm cutting protrusions 2023 of the main blade in the side cutting area 2093 of the main blade protrude relative to the main blade wide arm concave 2013 of the adjacent main cutting blade 20 and are close to the center line 2090 of the main cutting blade; the main blade wide arm inclined side 2012 protrudes relative to the main blade narrow arm inclined side 2022 of the adjacent main cutting blade 20 and is close to the center line 2090 of the main cutting blade. During the circuit breaker's disconnection process, the generated arc first enters the main plate side cutting area 2093. In this area, it is preferentially cut by contacting the protruding main plate wide arm bevel 2012 and the main plate narrow arm cutting protrusion 2023, and then by contacting the concave main plate narrow arm bevel 2022 and the main plate wide arm recess 2013. The arc is cut in batches within the main plate side cutting area 2093. Then, the arc enters the main plate main cutting area 2092, where it is cut by the relatively protruding main plate wide arm cutting protrusion 2014 of the two adjacent grid plates, thus extinguishing the arc. This achieves batch cutting and extinguishing of the arc in the second arc extinguishing group 2, reducing the difficulty of arc cutting and extinguishing.

[0055] like Figure 3As shown, a secondary cutting body 103 is provided on the side of the secondary cutting blade 10 near the end cap 8. From the secondary cutting body 103 towards the contact assembly 7, the secondary cutting blade 10 extends naturally to the left and right sides, respectively, with a secondary wide arm 101 and a secondary narrow arm 102. On the side of the secondary wide arm 101 facing the center line 1090 of the secondary cutting blade, from the secondary cutting body 103 towards the contact assembly 7, the following components are arranged in sequence: a secondary wide arm concave edge 1015, a secondary wide arm cutting protrusion 1014, a secondary wide arm concave 1013, a secondary wide arm inclined edge 1012, and a secondary wide arm edge 1011. On the side of the secondary narrow arm 102 facing the center line 1090 of the secondary cutting blade, from the secondary cutting body 103 towards the contact assembly 7, the following components are arranged in sequence: a secondary narrow arm concave edge 1024, a secondary narrow arm cutting protrusion 1023, a secondary narrow arm inclined edge 1022, and a secondary narrow arm edge 1021. The concave edge 1015 of the sub-piece wide arm and the concave edge 1024 of the sub-piece narrow arm are matched to form the main cutting area 1092 of the sub-piece. The concave edge 1015 of the sub-piece wide arm is closer to the center line 1090 of the sub-cutting piece than the concave edge 1024 of the sub-piece narrow arm. The concave edge 1013 of the sub-piece wide arm and the cutting protrusion 1023 of the sub-piece narrow arm are matched to form the side cutting area 1093 of the sub-piece. The cutting protrusion 1023 of the sub-piece narrow arm is closer to the center line 1090 of the sub-cutting piece than the concave edge 1013 of the sub-piece wide arm, and the cutting protrusion 1012 of the sub-piece wide arm is closer to the center line 1090 of the sub-cutting piece than the cutting protrusion 1022 of the sub-piece narrow arm. Several sub-cutting pieces 10 that make up the first arc extinguishing group 1 and the first arc extinguishing group 3 are arranged with adjacent sub-cutting pieces 10 rotated 180 degrees around the center line 1090 of the sub-cutting piece. Therefore, the sub-plate wide arm cutting protrusions 1014 of two adjacent grid plates in the sub-plate main cutting area 1092 are opposite each other, and the sub-plate narrow arm cutting protrusions 1023 of the sub-plate in the sub-plate side cutting area 1093 protrude near the sub-plate wide arm recess 1013 of the adjacent sub-plate 10, and are close to the sub-plate centerline 1090; the sub-plate wide arm inclined edge 1012 protrudes near the sub-plate narrow arm inclined edge 1022 of the adjacent sub-plate 10, and is close to the sub-plate centerline 1090. During the circuit breaker breaking process, the generated arc first enters the sub-plate side cutting area 1093. In this area, it preferentially contacts and is cut by contacting the protruding sub-plate wide arm inclined edge 1012 and the sub-plate narrow arm cutting protrusion 1023, and then contacts and is cut by contacting the recessed sub-plate narrow arm inclined edge 1022 and the sub-plate wide arm recess 1013, and is cut in batches in the sub-plate side cutting area 1093. Then, the arc enters the main cutting area 1092 of the sub-plate and cuts against the relatively protruding wide arm cutting protrusions 1014 of the adjacent two grid plates, thereby extinguishing the arc. This achieves batch cutting and extinguishing of the arc in the first arc extinguishing group 1 and the third arc extinguishing group 3, reducing the difficulty of arc cutting and extinguishing.

[0056] Figure 6As shown, the insulating shell 6 has several mounting grooves 604 on its left and right sides, each corresponding to the other. Positioning ridges 6041 are located on both sides of each mounting groove 604. The width of the mounting groove 604 matches the thickness of the main cutting disc 20 and the secondary cutting disc 10. Mounting holes 6042 are provided on each mounting groove 604. The position and size of the mounting holes 6042 are coupled to the main mounting protrusion 206 of the main cutting disc 20 and the secondary mounting protrusion 106 of the secondary cutting disc 10. On the side of the insulating shell 6 facing the contact assembly 7, first protective shells 601 are located on the left and right sides near the first arc-guiding plate 4, third protective shells 603 are located on the left and right sides near the second arc-guiding plate 5, and second protective shells 602 are located on the left and right sides in the middle. The first protective shells 601, second protective shells 602, and third protective shells 603 on the same side are naturally connected and transitioned sequentially. The main cutting blade 20 and the auxiliary cutting blade 10 are placed in corresponding mounting slots 604. The main piece mounting protrusion 204 of the main cutting blade 20 and the auxiliary piece mounting protrusion 104 of the auxiliary cutting blade 10 pass through the mounting hole 6042 to achieve the installation and positioning of the main cutting blade 20 and the auxiliary cutting blade 10 in the insulating shell 6. The main piece wide arm 201 and the main piece narrow arm 202 of the main cutting blade 20 are placed inside the second protective shell 602 of the insulating shell 6, and the second protective shell 602 provides insulation protection for the edge 2011 and the edge 2021 of the main piece wide arm. The auxiliary piece wide arm 101 and the auxiliary piece narrow arm 102 of the auxiliary cutting blade 10 are placed inside the first protective shell 601 and the third protective shell 603 of the insulating shell 6, and the first protective shell 601 and the third protective shell 603 protect the edge 1011 and the edge 1021 of the auxiliary piece wide arm.

[0057] like Figures 8 to 9 This diagram illustrates the process of an electric arc cutting through each arc-extinguishing group when a circuit breaker interrupts a fault current. The contact group 7 and the conducting element 9 begin to separate from each other, generating an electric arc between them. The arc moves towards the arc-extinguishing group due to the attraction of each group. At this time, one end of the arc adheres to the tip of the contact group 7, while the other end, attracted by the arc-extinguishing groups, leaves the conducting element 9 and moves sequentially along the jumper plate 402, connecting plate 403, and arc-fixing plate 404 of the first arc-initiating plate 4 towards the first arc-extinguishing group 1. As the contact group 7 moves further away from the conducting element 9, the arc is further elongated. At this point, the arc sequentially enters the secondary plate side cutting area 1093 and the secondary plate main cutting area 1092 of the first arc-extinguishing group 1, and the main plate side cutting area 2093 and the main plate main cutting area 2092 of the second arc-extinguishing group 2, cutting the grid plates in batches.

[0058] Figure 9As shown, when the contact group 7 moves to the termination position, the distance between the contact group 7 and the conductive element 9 reaches its maximum. At this time, the arcing arm 7102 of the long contact piece 71 of the contact group 7 moves from the main plate side cutting area 2093 of the second arc extinguishing group 2 to the auxiliary plate side cutting area 1093 of the third arc extinguishing group 3, and simultaneously enters the local magnetization area 50 of the second arc-initiating plate 5. At this time, the arcing arm 7102 maintains a distance of less than or equal to 5 mm from the contact plate 501, and the arc on it will contact the contact plate 501 of the second arc-initiating piece 5, and then extend from the contact plate 501 to the fixed arc plate 404. In this process, in addition to cutting with the main cutting piece 20 in the second arc extinguishing group 2, it further extends to the first arc extinguishing group 1 and cuts with the auxiliary cutting piece 10 in the first arc extinguishing group 1. After the arc cuts through the second arc-extinguishing group 2 and the first arc-extinguishing group 1, under the magnetization effect of the local magnetization zone 50, the arc extends further from the tip of the ignition arm 7102 of the long contact piece 71 of the contact group 7 through the contact plate 501 of the second arc-initiating piece 5 to the third arc-extinguishing group 3, thereby achieving sufficient cutting between the arc and the cutting pieces of each arc-extinguishing group. By cutting through each arc-extinguishing group sequentially, rather than simultaneously, the difficulty of the arc cutting into the arc-extinguishing group is reduced.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A contact arc extinguishing system, comprising a first arc extinguishing group (1), a second arc extinguishing group (2), a third arc extinguishing group (3), a first arc striking plate (4), a second arc striking plate (5), an insulating shell (6), a contact plate group (7), a conducting piece (9), and an end cover (8); the contact plate group (7) is opposite to the conducting piece (9); the first arc extinguishing group (1), the second arc extinguishing group (2), and the third arc extinguishing group (3) are arranged in the insulating shell (6); the first arc extinguishing group (1), the second arc extinguishing group (2), and the third arc extinguishing group (3) are arranged behind the contact plate group (7); the end cover (8) is arranged behind the first arc extinguishing group (1), the second arc extinguishing group (2), and the third arc extinguishing group (3); the first arc striking plate (4) is close to the conducting piece (9), and the first arc striking plate (4) is arranged below the first arc extinguishing group (1); the second arc striking plate (5) is arranged above the third arc extinguishing group (3); the first arc extinguishing group (1) and the third arc extinguishing group (3) are composed of a plurality of sub-cutting pieces (10); the second arc extinguishing group (2) is composed of a plurality of main cutting pieces (20); one end of the second arc striking plate (5) towards the contact group (7) is provided with a contact plate (501); characterized in that both sides of the contact plate (501) of the second arc striking plate (5) are provided with magnetic enhancement plates (504), and the contact plate (501) and the magnetic enhancement plates (504) form a local magnetic enhancement area (50). one end of the second arc striking plate (5) towards the third arc extinguishing group (3) is provided with an extension plate (503); the extension plate (503) is arranged at the upper end of the third arc extinguishing group (3); the extension plate (503) is arranged in parallel with the sub-cutting pieces (10) of the third arc extinguishing group (3); 2. A contact arc quenching system as claimed in claim 1, characterized in that the contact plate (501) is bent out at the central position of one end of the extension plate (503) towards the contact group (7); transition plates (502) are bent out at both sides of the contact plate (501) of one end of the extension plate (503) towards the contact group (7); magnetic enhancement plates (504) are bent out from the transition plates (502) towards the contact plate (501); the magnetic enhancement plates (504) and the contact plate (501) form a local magnetic enhancement area (50). one end of the conducting piece (9) towards the contact group (7) is a contact section (901); the contact section (901) is fixed with a static main contact (904) and a static sub-contact (905) on one side thereof towards the contact group (7); 3. A contact arc quenching system as claimed in claim 1, wherein, one end of the conducting piece (9) away from the contact group (7) is a connecting section (903); the connecting section (903) is arranged perpendicularly to the contact section (901); the connecting section (903) and the contact section (901) are naturally and smoothly connected through an inclined transition section (902). a long contact plate (71) is arranged in the center of the contact group (7); a plurality of second contact plates (72) and a plurality of short contact plates (73) are arranged in sequence on both sides of the contact group (7).

4. A contact arc quenching system as claimed in claim 1, wherein, ​ The long contact piece (71) is provided with a moving main contact (7103) and a moving auxiliary contact (7104) on one side facing the conducting part (9); the moving main contact (7103) is opposite to the static main contact (904); the moving auxiliary contact (7104) is opposite to the static auxiliary contact (905); the long contact piece (71) automatically extends the arc arm (7102) from the moving auxiliary contact (7104) to the second arc striking plate (5) naturally. The second contact piece (72) is provided with a second main contact (7203) and a second auxiliary contact (7204) on one side facing the conducting part (9); the second main contact (7203) is opposite to the static main contact (904); the second auxiliary contact (7204) is opposite to the static auxiliary contact (905); The short contact piece (73) is provided with a third main contact (7303) on one side facing the conducting part (9); the third main contact (7303) is opposite to the static main contact (904).

5. A contact arc quenching system as claimed in claim 1, wherein, The first arc striking plate (4) is provided with an inclined mounting plate (401) on one end facing the conducting part (9); the mounting plate (401) is attached to the transition section (902) of the conducting part (9); The first arc striking plate (4) bends out the jump plate (402) from the mounting plate (401) facing the contact group (7); the jump plate (402) is horizontal to the contact section (901) on the conducting part (9); the jump plate (402) is flush with the auxiliary contact (905); The first arc striking plate (4) is provided with the arc setting plate (404) on one end facing the first arc extinguishing group (1); the arc setting plate (404) is placed below the first arc extinguishing group (1); the arc setting plate (404) is arranged in parallel with the auxiliary cutting piece (10) of the first arc extinguishing group (1); The jump plate (402) and the arc setting plate (404) are naturally connected through the inclined connecting plate (403); The first arc striking plate (4) bends out the fixed plate (405) from the mounting plate (401) facing away from the contact group (7).

6. An arc contact quenching system according to claim 1, wherein The main cutting piece (20) is provided with the main piece cutting body (203) on one side close to the end cover (8); The main cutting piece (20) naturally extends out the main piece wide arm (201) and the main piece narrow arm (202) from the main piece cutting body (203) to the contact group (7) on both sides respectively; The main piece wide arm (201) is naturally arranged in sequence from the main piece cutting body (203) to the contact group (7) on one side facing the main cutting piece center line (2090) with the main piece wide arm flange (2015), the main piece wide arm cutting convex (2014), the main piece wide arm concave (2013), the main piece wide arm bevel (2012), and the main piece wide arm edge (2011); The main piece narrow arm (202) is naturally arranged in sequence from the main piece cutting body (203) to the contact group (7) on one side facing the main cutting piece center line (2090) with the main piece narrow arm flange (2024), the main piece narrow arm cutting convex (2023), the main piece narrow arm bevel (2022), and the main piece narrow arm edge (2021); The main piece wide arm flange (2015) and the main piece narrow arm flange (2024) are matched oppositely, and together constitute a main piece main cutting area (2092), and the main piece wide arm flange (2015) is closer to the main cutting piece center line (2090) than the main piece narrow arm flange (2024); The main piece wide arm flange (2015) and the main piece narrow arm flange (2024) are matched oppositely, and together constitute a main piece main cutting area (2092), and the main piece wide arm flange (2015) is closer to the main cutting piece center line (2090) than the main piece narrow arm flange (2024); 7. An arc contact quenching system according to claim 1, wherein The auxiliary cutting piece (10) is provided with an auxiliary piece cutting body (103) on one side close to the end cover (8); The auxiliary cutting piece (10) is naturally and gradually extended to the auxiliary piece wide arm (101) and the auxiliary piece narrow arm (102) from the auxiliary piece cutting body (103) to the touch piece group (7) on both sides; The auxiliary piece wide arm (101) is naturally and gradually arranged in sequence from the auxiliary piece cutting body (103) to the touch piece group (7) on one side close to the auxiliary cutting piece center line (1090) in the order of the auxiliary piece wide arm flange (1015), the auxiliary piece wide arm cutting convex (1014), the auxiliary piece wide arm concave (1013), the auxiliary piece wide arm bevel (1012), and the auxiliary piece wide arm edge (1011); The auxiliary piece narrow arm (102) is naturally and gradually arranged in sequence from the auxiliary piece cutting body (103) to the touch piece group (7) on one side close to the auxiliary cutting piece center line (1090) in the order of the auxiliary piece narrow arm flange (1024), the auxiliary piece narrow arm cutting convex (1023), the auxiliary piece narrow arm bevel (1022), and the auxiliary piece narrow arm edge (1021); The auxiliary piece wide arm flange (1015) and the auxiliary piece narrow arm flange (1024) are matched oppositely, and together constitute an auxiliary piece main cutting area (1092), and the auxiliary piece wide arm flange (1015) is closer to the auxiliary cutting piece center line (1090) than the auxiliary piece narrow arm flange (1024); The auxiliary piece wide arm flange (1015) and the auxiliary piece narrow arm flange (1024) are matched oppositely, and together constitute an auxiliary piece main cutting area (1092), and the auxiliary piece wide arm flange (1015) is closer to the auxiliary cutting piece center line (1090) than the auxiliary piece narrow arm flange (1024); 8. An arc contact quenching system according to claim 1, wherein The insulating shell (6) is provided with a plurality of installation grooves (604) on both sides in one-to-one correspondence; The auxiliary piece wide arm flange (1015) and the auxiliary piece narrow arm flange (1024) are matched oppositely, and together constitute an auxiliary piece main cutting area (1092), and the auxiliary piece wide arm flange (1015) is closer to the auxiliary cutting piece center line (1090) than the auxiliary piece narrow arm flange (1024); The one side of the insulating shell (6) is provided with the first protective shell (601) near the first arc striking plate (4), the third protective shell (603) near the second arc striking plate (5), and the second protective shell (602) in the middle.

9. A contact arc quenching system as claimed in claim 6, wherein, The main wide arm (201) and the main narrow arm (202) of the main cutting blade (20) are arranged in the second protective shell (602) of the insulating shell (6).

10. A contact arc extinguishing system according to claim 7, characterized in that The auxiliary wide arm (101) and the auxiliary narrow arm (102) of the auxiliary cutting blade (10) are arranged in the first protective shell (601) and the third protective shell (603) of the insulating shell (6).

Images