Monostable permanent-magnetic circuit breaker switch for air tank

Abstract

The application discloses a single-stable permanent magnetic circuit breaker switch for air tank, which comprises a fixed sealed pole, a permanent magnetic mechanism component, a soft connection, an insulating pull rod component, a opening transmission component and a terminal box fixed on a switch frame; wherein the switch frame comprises a frame front plate, a frame back plate and a mounting pocket plate; the mounting pocket plate is in U shape; the fixed sealed pole comprises a solidified and formed insulating shell, a silicon rubber arc extinguishing chamber, a conductive terminal and a fastening insert; and the conductive terminal fastened with the arc extinguishing chamber is located at the lower end of the insulating shell. The conductive terminal outer convex platform tightly presses the silicon rubber, effectively avoids the pouring solidification of the epoxy resin on the lap joint surface between the arc extinguishing chamber static guide rod and the conductive terminal, and after solidification, the silicon rubber is tightly held by the insulating shell under the extrusion of the outer convex platform, the inner flange and the insulating shell, and the air gap is eliminated.

Description

Technical Field

[0001] This invention relates to a high-voltage power supply equipment, specifically a monostable permanent magnet circuit breaker switch for an air-cooled cabinet. Background Technology

[0002] SF6 gas, as an excellent gas insulator with good chemical stability, is widely used for gas insulation in electronic and electrical equipment. Although sulfur hexafluoride itself is non-toxic and harmless to humans, it is a greenhouse gas; its single-molecule greenhouse effect is 22,000 times that of carbon dioxide, and it is one of the six greenhouse gases banned from emission under the Kyoto Protocol. While current sulfur hexafluoride emissions are relatively low, for long-term environmental and safety considerations, the power industry urgently needs environmentally friendly switchgear to replace sulfur hexafluoride-insulated switchgear. Traditional permanent magnet circuit breakers use the following method for tripping: an insulating rod and a stationary magnet mutually limit each other; during tripping, the insulating rod strikes the stationary magnet, and a limit device is installed on the upper end of the moving magnet. Both of these tripping limit methods generate forces that act directly on the stationary or moving magnet, easily damaging the magnets and affecting their service life. Meanwhile, in circuit breakers currently using solid-insulated poles, most solid-insulated poles are prone to air gaps due to poor manufacturing process control. The presence of these air gaps causes uneven electric fields in different areas, resulting in a decrease in local electrical strength within the insulation compared to the electric field strength, leading to localized breakdown. Furthermore, epoxy resin material can easily seep into the contact surface between the arc-extinguishing chamber and the conductive terminal, further reducing the current conduction performance between them. Therefore, further improvements are necessary. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a monostable permanent magnet circuit breaker switch that has a simple structure, reduces the force on the magnet when opening, reduces the air gap in the solid-sealed pole, and can operate in dry air.

[0004] The objective of this invention is achieved in the following way: a monostable permanent magnet circuit breaker switch for air-operated cabinets, characterized in that: it includes a solid-sealed pole fixed on the switch frame, a permanent magnet mechanism assembly, a flexible connection, an insulating pull rod assembly, a tripping transmission assembly, and a junction box; Wherein: the switch frame includes a front frame plate, a rear frame plate, and a mounting bracket; the mounting bracket is U-shaped; Wherein: the solid-sealed pole includes a cured insulating shell, an arc-extinguishing chamber with silicone rubber, a conductive terminal and a fastening insert; the conductive terminal fastened to the arc-extinguishing chamber is located at the lower end of the insulating shell; the fastening insert is located at the upper end of the insulating shell; the insulating shell has a cavity for accommodating the flexible connection and insulating pull rod assembly; the solid-sealed pole is installed below the switch frame through the fastening insert. Wherein: the permanent magnet mechanism component includes a stationary magnet, a moving magnet, and a tripping spring; the stationary magnet is mounted on a mounting plate, and has a coil on it; the stationary magnet and the moving magnet have cavities to accommodate the tripping spring; the upper end of the moving magnet has a connecting plate that connects to the tripping transmission assembly. Wherein: one end of the insulating pull rod assembly is connected to the moving end magnet, and the other end is fixed to the moving conductive rod of the arc-extinguishing chamber via a flexible connection; Wherein: the opening transmission assembly includes a main shaft and a crank arm for connecting with the connecting plate. The rear end of the main shaft is movably mounted on the rear plate of the frame, and the main shaft is located above and to the side of the moving end magnet. Wherein: the junction box is installed on the mounting bracket, and the wires led out from the coil in the permanent magnet mechanism assembly are all connected to the junction box; Wherein: the insulating tie rod assembly is provided with a limiting platform, which is positioned below the mounting bracket when the circuit breaker switch is in the open state.

[0005] The insulating pull rod assembly includes an insulating cylinder, a connecting pull rod, a compression spring, a compression cap, and a double-ended screw. The insulating cylinder is formed by epoxy resin casting of a large insert and a small insert. The large and small inserts are spaced apart, and both have spherical surfaces on their adjacent sides. The large insert has a cavity structure to accommodate the connecting pull rod, the compression spring, and the compression cap. The compression spring is placed inside the large insert. The connecting pull rod has a flange structure in the middle, and its inner end is placed in the large insert. The inner part is connected to the compression spring, and the middle part of the compression cap is a through hole. The outer end of the connecting rod is connected to the through hole of the compression cap. The compression cap presses against the flange part of the connecting rod and is tightened on the large insert. The preload of the compression spring is adjusted by the compression cap. The flexible connection is fixed to the moving conductive rod of the arc-extinguishing chamber in the solid-sealed pole by the fastening nut on the connecting rod. The lower end of the double-ended screw is connected to the small insert. A limiting platform is provided on the double-ended screw near the small insert. The upper end of the double-ended screw is connected to the moving end magnet.

[0006] The permanent magnet mechanism assembly is also provided with a guide sleeve, which is installed on the middle through hole of the stationary magnet. The lower end of the guide sleeve is provided with an outer flange, and the stationary magnet is provided with a cavity to accommodate the outer flange. The double-ended screw is installed through the guide sleeve.

[0007] The conductive terminal is provided with a groove, an inner boss is formed on one side of the inner wall of the groove, and an outer boss is formed on one side of the outer wall of the groove. The outer boss is higher than the inner boss. The end face of the inner boss is in contact with the end face of the static conductive rod of the arc-extinguishing chamber. The outer boss compresses the silicone rubber on the arc-extinguishing chamber.

[0008] The conductive terminal is also provided with a vent hole, which extends from the groove to the other side of the conductive terminal.

[0009] The inner wall of the insulating shell is provided with an inner flange, which extends to the silicone rubber flat surface of the moving end cover plate of the arc extinguishing chamber.

[0010] The limiting platform of the double-ended screw is equipped with a buffer pad.

[0011] A pad is also installed above the cushioning pad.

[0012] The mounting plate is equipped with a support plate, which supports the underside of the main shaft.

[0013] The moving end magnet has two connecting plates, which are symmetrically arranged on the moving end magnet.

[0014] The beneficial effects of this invention are: 1. Simple structure, low production cost, and improved market competitiveness. 2. The outer protrusion of the conductive terminal presses tightly against the silicone rubber, effectively preventing epoxy resin from flowing into the overlapping surface between the static guide rod of the arc-extinguishing chamber and the conductive terminal during casting and curing; moreover, after curing, under the pressure of the outer protrusion, inner flange, and insulating shell, the silicone rubber is held tightly by the insulating shell, eliminating air gaps. 3. After the arc-extinguishing chamber and conductive terminal are fastened, a cavity structure exists. The heat generated in the cavity structure when the solidified pole is energized can be discharged through the vent holes, increasing the heat dissipation capacity of the equipment. 4. The large and small inserts on the insulating tie rod assembly have spherical surfaces on the side where they are close to each other. The uniform electric field of the spherical surface improves the insulation capacity of the insulating tie rod assembly, while reducing the overall length of the insulating tie rod, which also reduces the overall height of the solidified pole; moreover, the spherical surfaces of the large and small inserts can disperse the forces on the insulating tie rod assembly, reduce stress concentration, and improve the structural strength of the insulating tie rod assembly. 4. When the circuit breaker is opened, the force of the limit switch is applied to the switch frame, preventing the force from acting on the stationary magnet. Simultaneously, the buffer pad absorbs the impact force between the limit switch and the switch frame during opening, reducing the rebound amplitude of the switch after opening. 5. The pad above the buffer pad protects it, preventing damage from direct impact with the switch frame. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the switch structure.

[0016] Figure 2 This is a schematic diagram of the switch frame structure.

[0017] Figure 3 This is a cross-sectional diagram of a solid-sealed pole.

[0018] Figure 4 This is a cross-sectional diagram of a conductive terminal.

[0019] Figure 5 This is a partially enlarged schematic diagram of the conductive terminal portion in a solid-sealed electrode post.

[0020] Figure 6 This is a partially enlarged schematic diagram of the inner flange portion of the solid-sealed pole.

[0021] Figure 7 This is a cross-sectional schematic diagram of a permanent magnet mechanism component.

[0022] Figure 8 This is a cross-sectional schematic diagram of the insulated tie rod assembly.

[0023] In the diagram: 1-Switch frame, 11-Front frame plate, 12-Rear frame plate, 13-Mounting bracket, 14-Support plate; 2-Fixed pole post, 21-Insulating shell, 211-Inner flange, 22-Arc extinguishing chamber, 23-Silicone rubber, 24-Conductive terminal, 241-Groove, 242-Inner boss, 243-Outer boss, 244-Ventilation hole, 25-Fastening insert; 3-Permanent magnet mechanism assembly, 31-Stationary magnet, 32-Moving magnet Magnet, 33-Closing spring, 34-Connecting plate, 35-Guide sleeve, 351-Outer flange; 4-Flexible connection; 5-Insulating pull rod assembly, 51-Pull rod insulating cylinder, 511-Large insert, 512-Small insert, 52-Connecting pull rod, 53-Compression spring, 54-Compression cap, 55-Double-ended screw, 551-Limiting platform, 56-Buffer pad, 57-Washer; 6-Closing transmission assembly, 61-Main shaft, 62-Crank arm; 7-Junction box. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings. A monostable permanent magnet circuit breaker switch for an air switchgear is characterized in that it includes a solid-sealed pole post 2 fixed on a switch frame 1, a permanent magnet mechanism assembly 3, a flexible connection 4, an insulating pull rod assembly 5, a tripping transmission assembly 6, and a junction box 7; Wherein: the switch frame 1 includes a front frame plate 11, a rear frame plate 12, and a mounting pocket 13; the mounting pocket 13 is U-shaped; Wherein: the solidified pole 2 includes a cured insulating shell 21, an arc-extinguishing chamber 22 with silicone rubber 23, a conductive terminal 24, and a fastening insert 25; the conductive terminal 24, which is fastened to the arc-extinguishing chamber 22, is located at the lower end of the insulating shell 21; the fastening insert 25 is located at the upper end of the insulating shell 21; the insulating shell 21 has a cavity for accommodating the flexible connection 4 and the insulating pull rod assembly 5; the solidified pole 2 is installed below the switch frame 1 through the fastening insert 25; Wherein: the permanent magnet mechanism component 3 includes a stationary magnet 31, a moving magnet 32 ​​and a tripping spring 33; the stationary magnet 31 is mounted on the mounting bracket 13, and the stationary magnet 31 has a coil on it; the stationary magnet 31 and the moving magnet 32 ​​are provided with cavities to accommodate the tripping spring 33; the upper end of the moving magnet 32 ​​is provided with a connecting plate 34 that is connected to the tripping transmission component 6; Wherein: one end of the insulating pull rod assembly 5 is connected to the moving end magnet 32, and the other end fixes the flexible connection 4 to the moving conductive rod of the arc-extinguishing chamber 22; Wherein: the opening transmission assembly 6 includes a main shaft 61 and a crank arm 62 for connecting to the connecting plate 34. The rear end of the main shaft 61 is movably mounted on the rear plate 12 of the frame, and the main shaft 61 is located above and to the side of the moving end magnet 32. Wherein: the junction box 7 is installed on the mounting bracket 13, and the wires led out from the coil in the permanent magnet mechanism assembly 3 are all connected to the junction box 7; Wherein: the insulating tie rod assembly 5 is provided with a limiting platform 551, which is positioned below the mounting bracket 13 when the circuit breaker switch is in the open state.

[0025] The insulating pull rod assembly 5 includes a pull rod insulating cylinder 51, a connecting pull rod 52, a compression spring 53, a pressure cap 54, and a double-ended screw 55. The pull rod insulating cylinder 51 is obtained by epoxy resin casting of a large insert 511 and a small insert 512. The large insert 511 and the small insert 512 are spaced apart, and both the large insert 511 and the small insert 512 have spherical surfaces on the side where they are close to each other. The large insert 511 has a cavity structure to accommodate the connecting pull rod 52, the compression spring 53, and the pressure cap 54. The compression spring 53 is placed inside the large insert 511. The connecting pull rod 52 has a flange structure in the middle, and the inner end of the connecting pull rod 52 is placed inside the large insert 511. The insert 511 is connected in series with the compression spring 53. The middle part of the pressure cap 54 is a through hole. The outer end of the connecting rod 52 is connected in series in the through hole of the pressure cap 54. The pressure cap 54 presses against the flange part of the connecting rod 52 and is tightened on the large insert 511. The pressure cap 54 is used to adjust the preload of the compression spring 53. The flexible connection 4 is fixed to the moving conductive rod of the arc-extinguishing chamber 22 in the solid-sealing pole post 2 by the fastening nut on the connecting rod 52. The lower end of the double-ended screw 55 is connected to the small insert 512. A limiting platform 551 is provided on the double-ended screw 55 near the small insert 512. The upper end of the double-ended screw 55 is connected to the moving end magnet 32.

[0026] The permanent magnet mechanism assembly 3 is also provided with a guide sleeve 35, which is installed on the middle through hole of the stationary magnet 31. The lower end of the guide sleeve 35 is provided with an outer flange 351, and a cavity is provided on the stationary magnet 31 to accommodate the outer flange 351. The double-ended screw 55 is installed through the guide sleeve 35.

[0027] The conductive terminal 24 is provided with a groove 241, an inner boss 242 is formed on one side of the inner wall of the groove 241, and an outer boss 243 is formed on one side of the outer wall of the groove 241. The outer boss 243 is higher than the inner boss 242. The end face of the inner boss 242 is in contact with the end face of the stationary conductive rod of the arc-extinguishing chamber 22. The outer boss 243 compresses the silicone rubber 23 on the arc-extinguishing chamber 22.

[0028] The conductive terminal 24 is also provided with a vent hole 244, which extends from the groove 241 to the other side of the conductive terminal 24.

[0029] The inner wall of the insulating shell 21 is provided with an inner flange 211, which extends to the flat surface of the silicone rubber 23 on the moving end cover of the arc-extinguishing chamber 22.

[0030] The limiting platform 551 of the double-headed screw 55 is equipped with a buffer pad 56.

[0031] A pad 57 is also installed above the buffer pad 56.

[0032] The mounting plate 13 is provided with a support plate 14, which supports the underside of the main shaft 61.

[0033] The moving end magnet 32 ​​has two connecting plates 34, which are symmetrically arranged on the moving end magnet 32.

[0034] Working principle: When the coil is energized, the stationary magnet 31 generates electromagnetic force and attracts the moving magnet 32. The moving magnet 32 ​​drives the insulating pull rod to move downward, completing the switch closing. When the coil is energized in the reverse direction, the stationary magnet 31 generates repulsive force and separates from the moving magnet 32. The moving magnet 32 ​​drives the insulating pull rod assembly 5 to move upward, completing the switch opening. When the main shaft 61 is rotated by external force, the crank arm 62 drives the moving magnet 32 ​​to move upward, and the moving magnet 32 ​​and the stationary magnet 31 are released from the attraction state, completing the manual opening of the switch.

[0035] Compared with traditional technologies, the structure in this case has the following advantages: 1. The outer protrusion of the conductive terminal tightly presses against the silicone rubber, effectively preventing epoxy resin from flowing into the overlapping surface between the static guide rod of the arc-extinguishing chamber and the conductive terminal during casting and curing; moreover, after curing, under the compression of the outer protrusion, inner flange, and insulating shell, the silicone rubber is held tightly by the insulating shell, eliminating air gaps; 2. After the arc-extinguishing chamber and conductive terminal are fastened, a cavity structure exists. The heat generated in the cavity structure when the sealed pole is energized can be discharged through the vent holes, thereby increasing the heat dissipation capacity of the equipment. 3. The large and small inserts on the insulating tie rod assembly have spherical surfaces on the side where they are close to each other. The uniform electric field of the spherical surface improves the insulation capacity of the insulating tie rod assembly, while reducing the overall length of the insulating tie rod, which also reduces the overall height of the sealed pole; moreover, the spherical surfaces of the large and small inserts can disperse the forces on the insulating tie rod assembly, reduce stress concentration, and improve the structural strength of the insulating tie rod assembly. 4. The guide sleeve reduces the sway of the insulating pull rod assembly, ensuring that the moving and stationary magnets are aligned during switch opening and closing, resulting in more stable operation when the device closes. 5. During opening, the force of the limit plate is applied to the switch frame, preventing the force from acting on the stationary magnet. Simultaneously, the buffer pad absorbs the impact force between the limit plate and the switch frame during opening, reducing the rebound amplitude of the switch after opening. The gasket above the buffer pad protects it from damage due to direct impact with the switch frame. 6. During manual opening, the main shaft experiences a downward reaction force, causing bending deformation. The support plate supports the lower part of the main shaft, offsetting the reaction force and reducing deformation, ensuring reliable manual opening of the switch. The support plate also strengthens the middle of the mounting bracket, improving the overall strength of the switch frame. Therefore, the product of this invention can operate safely in dry air, has a simple and compact structure, small size, and is easy to assemble, making it widely applicable.

[0036] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of the claims of this invention.

Claims

1. A monostable permanent magnetic circuit breaker switch for air tanks, characterized by: It includes a solid-sealed pole (2) fixed on the switch frame (1), a permanent magnet mechanism assembly (3), a flexible connection (4), an insulating pull rod assembly (5), a tripping drive assembly (6), and a junction box (7); Wherein: the switch frame (1) includes a front frame plate (11), a rear frame plate (12), and a mounting pocket (13); the mounting pocket (13) is U-shaped; Wherein: the solid-sealed pole (2) includes a cured insulating shell (21), an arc-extinguishing chamber (22) with silicone rubber (23), a conductive terminal (24) and a fastening insert (25); the conductive terminal (24) fastened to the arc-extinguishing chamber (22) is located at the lower end of the insulating shell (21); the fastening insert (25) is located at the upper end of the insulating shell (21); the insulating shell (21) has a cavity for accommodating the flexible connection (4) and the insulating pull rod assembly (5); the solid-sealed pole (2) is installed below the switch frame (1) through the fastening insert (25); The permanent magnet mechanism component (3) includes a stationary magnet (31), a moving magnet (32), and a trip spring (33). The stationary magnet (31) is mounted on the mounting plate (13), and the stationary magnet (31) has a coil. The stationary magnet (31) and the moving magnet (32) are provided with cavities to accommodate the trip spring (33). The upper end of the moving magnet (32) is provided with a connecting plate (34) that is connected to the trip transmission component (6). Wherein: one end of the insulating pull rod assembly (5) is connected to the moving end magnet (32), and the other end fixes the flexible connection (4) to the moving conductive rod of the arc-extinguishing chamber (22); Wherein: the opening transmission assembly (6) includes a main shaft (61) and a crank arm (62) for connecting to the connecting plate (34). The rear end of the main shaft (61) is movably mounted on the rear plate (12) of the frame, and the main shaft (61) is located above the moving end magnet (32). Wherein: the junction box (7) is installed on the mounting bracket (13), and the wires led out from the coil in the permanent magnet mechanism assembly (3) are all connected to the junction box (7); Wherein: the insulating tie rod assembly (5) is provided with a limiting platform (551), and when the circuit breaker switch is in the open state, the limiting platform (551) is positioned below the mounting bracket (13); The conductive terminal (24) is provided with a groove (241), an inner boss (242) is formed on one side of the inner wall of the groove (241), and an outer boss (243) is formed on one side of the outer wall of the groove (241). The outer boss (243) is higher than the inner boss (242). The end face of the inner boss (242) is in contact with the end face of the stationary conductive rod of the arc-extinguishing chamber (22). The outer boss (243) squeezes the silicone rubber (23) on the arc-extinguishing chamber (22). The inner wall of the insulating shell (21) is provided with an inner flange (211), which extends to the flat surface of the silicone rubber (23) of the moving end cover of the arc-extinguishing chamber (22).

2. A monostable permanent magnetic circuit breaker switch for air tanks according to claim 1, characterized in that: The insulating pull rod assembly (5) includes a pull rod insulating cylinder (51), a connecting pull rod (52), a compression spring (53), a pressure cap (54), and a double-ended screw (55). The pull rod insulating cylinder (51) is obtained by epoxy resin casting of a large insert (511) and a small insert (512). The large insert (511) and the small insert (512) are spaced apart, and both the large insert (511) and the small insert (512) have spherical surfaces on the side where they are close to each other. The large insert (511) has a cavity structure to accommodate the connecting pull rod (52), the compression spring (53), and the pressure cap (54). The compression spring (53) is placed inside the large insert (511). The connecting pull rod (52) has a flange structure in the middle, and the inner end of the connecting pull rod (52) is placed inside the large insert (511). The insert (511) is connected in series with the compression spring (53). The middle part of the pressure cap (54) is a through hole. The outer end of the connecting rod (52) is connected in series in the through hole of the pressure cap (54). The pressure cap (54) presses against the flange part of the connecting rod (52) and is tightened on the large insert (511). The pressure cap (54) is used to adjust the preload of the compression spring (53). The flexible connection (4) is fixed on the moving conductive rod of the arc-extinguishing chamber (22) in the solid-sealing pole (2) by the fastening nut on the connecting rod (52). The lower end of the double-ended screw (55) is connected to the small insert (512). A limiting platform (551) is provided on the double-ended screw (55) near the small insert (512). The upper end of the double-ended screw (55) is connected to the moving end magnet (32).

3. A monostable permanent magnetic circuit breaker switch for air tanks as claimed in claim 1, wherein: The permanent magnet mechanism assembly (3) is also provided with a guide sleeve (35), which is installed on the middle through hole of the stationary magnet (31). The lower end of the guide sleeve (35) is provided with an outer flange (351), and a cavity is provided on the stationary magnet (31) to accommodate the outer flange (351). The double-headed screw (55) is installed through the guide sleeve (35).

4. A monostable permanent magnetic circuit breaker switch for air tanks as claimed in claim 1, wherein: The conductive terminal (24) is also provided with a vent hole (244), which extends from the groove (241) to the other side of the conductive terminal (24).

5. A monostable permanent magnetic circuit breaker switch for air tanks as claimed in claim 3, wherein: The limiting platform (551) of the double-headed screw (55) is equipped with a buffer pad (56).

6. A monostable permanent magnetic circuit breaker switch for air tanks according to claim 5, characterized in that: A pad (57) is also installed on top of the buffer pad (56).

7. A monostable permanent magnetic circuit breaker switch for air tanks as claimed in claim 1, wherein: The mounting plate (13) is provided with a support plate (14), which supports the bottom of the main shaft (61).

8. A monostable permanent magnetic circuit breaker switch for air tanks as claimed in claim 1, wherein: The moving end magnet (32) has two connecting plates (34), which are symmetrically arranged on the moving end magnet (32).

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