A switch cabinet using clean air as insulating medium

Abstract

The present invention discloses a switch cabinet using clean air as an insulating medium, specifically relating to the technical field of power equipment. The switch cabinet using clean air as an insulating medium comprises a cabinet body, an air box, a fixed plate, a sealing spacer, a cylindrical sleeve, a clamping sleeve, a sealing ring; a contraction unit; and an air supply unit, which is arranged in the air box and is used to supply gas to the interior of the air box when the clamping sleeve contracts. In the present invention, the contraction unit will be triggered and drive the clamping sleeve to produce elastic contraction deformation, thereby clamping the sealing ring on the wall of the cable hole, so that the sealing ring and the surface of the cable are in closer contact, reducing leakage between the cable and the cable hole. In addition, when the air pressure in the air box drops, the air supply unit will be activated, thereby replenishing gas into the air box, increasing the air pressure in the air box, and maintaining a positive pressure state in the air box for a short time, thereby increasing the concentration of the insulating gas medium in the air box, and preventing a significant impact on the arc extinguishing of the air box.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric power equipment, and in particular relates to a switch cabinet using clean air as an insulating medium. Background Art

[0002] A switchgear is a type of electrical equipment. External wiring in the switchgear first enters the main control switch inside the switchgear, then passes to the branch switches. Each branch is configured according to its specific needs. These include instruments, automatic controls, motor magnetic switches, and various AC contactors. Some switchgear also has high-voltage and low-voltage compartments, with high-voltage busbars, such as in power plants. Some also have low-frequency load shedding to protect key equipment. The primary function of a switchgear is to open and close, control, and protect electrical equipment during power generation, transmission, distribution, and conversion. The components within a switchgear primarily include circuit breakers, disconnectors, load switches, operating mechanisms, instrument transformers, and various protective devices. Switchgear can be categorized in many ways. For example, circuit breaker mounting methods can categorize it into removable and fixed types; cabinet structure can also categorize it into open, metal-enclosed, and metal-clad types; and voltage levels can further categorize it into high-voltage, medium-voltage, and low-voltage types. It is mainly suitable for various occasions such as power plants, substations, petrochemical industry, metallurgy and steel rolling, light industry and textile, factories and mines, residential areas, high-rise buildings, etc.

[0003] After searching, Chinese patent publication number CN206533038U discloses a switch cabinet that can avoid overvoltage damage to the voltage transformer caused by three-phase imbalance due to voltage instability. This switch cabinet includes a switch cabinet frame, an air box and a cable chamber, wherein the air box and the cable chamber are located within the switch cabinet frame, and the air box is located above the cable chamber. The switch cabinet also includes a transformer chamber arranged on the back of the switch cabinet frame, and the transformer chamber includes: a mounting frame, which is mounted on the switch cabinet frame; a three-phase voltage transformer, which is mounted on the mounting frame; a cable, one end of which is connected to the voltage transformer and the other end is connected to the cable chamber; and a housing, which is fixed to the mounting frame and covers the transformer chamber; wherein the voltage transformer adopts a delta connection.

[0004] In the above technical solution, the electrical equipment installed in the gas box is mainly connected to other electrical equipment in the switch cabinet through cables. However, since the cables pass through the gas box casing, and under normal circumstances, the inside of the gas box is in a positive pressure state, that is, the gas pressure in the gas box is greater than the normal pressure, there is a possibility of gas leakage at the connection between the cable and the gas box, which in turn causes the gas concentration in the gas box to decrease. For example, when the SF6 gas concentration decreases, the arc extinguishing effect may be affected. Therefore, it is necessary to design a switch cabinet that can timely reduce the leakage amount when gas leakage occurs. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the disadvantages of the above-mentioned prior art and provide a switch cabinet using clean air as the insulating medium.

[0006] The technical solution adopted to solve the above technical problems is: a switch cabinet using clean air as the insulating medium, comprising a switch cabinet body and an air box installed in the cabinet body, wherein the air box shell is provided with multiple cable through-holes, and further comprising:

[0007] A fixed plate is mounted on the gas box housing, and a sealing sleeve is fixedly connected to the end surface thereof and is inserted into the cable opening, wherein the sealing sleeve is provided with a cable hole;

[0008] A cylindrical sleeve is coaxially fixed to one end of the sealing sleeve that passes into the air box, and a clamping sleeve is coaxially fixed to the other end away from the sealing sleeve. The clamping sleeve is provided with a cable threading hole that passes through the cylindrical sleeve, and a plurality of deformation seams that communicate with the cable threading holes are provided on the periphery of the clamping sleeve. A sealing ring installation groove is coaxially provided in the clamping sleeve, and a sealing ring is installed in the sealing ring installation groove.

[0009] A contraction unit is provided on the sealing spacer and is used to drive the clamping sleeve to contract when the pressure inside the air box is lost;

[0010] The air supply unit is arranged in the air box and is used to supply air to the interior of the air box when the clamping sleeve contracts.

[0011] Through the above technical solution, the cable hole and the outer wall of the cable are in a sealed state. When the gas pressure in the gas box drops, the contraction unit will be triggered and drive the clamping sleeve to produce elastic contraction deformation, thereby clamping the sealing ring of the cable hole wall, making the sealing ring and the surface contact of the cable closer, and the deformation joint is also closed, thereby reducing the leakage between the cable and the cable hole. In addition, when the air pressure in the gas box drops, the air replenishing unit will be activated, thereby replenishing gas into the gas box, increasing the air pressure in the gas box, thereby maintaining the positive pressure state in the gas box in a short time, and increasing the concentration of the insulating gas medium in the gas box to prevent a major impact on the arc extinguishing of the gas box, and giving the operation and maintenance personnel enough time to reach the site for operation and maintenance. In addition, under normal use, the clamping force of the clamping sleeve on the sealing ring is small, thereby preventing the sealing ring from being deformed by clamping the cable for a long time, affecting the sealing effect of the sealing ring on the cable.

[0012] Furthermore, the shrinkage unit includes a sealing sleeve that is slidably mounted on the periphery of the cylindrical sleeve, and an extrusion sleeve is coaxially fixed to one end of the sealing sleeve away from the sealing spacer. The outer diameter of the clamping sleeve increases successively in the direction away from the sealing spacer. The extrusion sleeve is coaxially provided with a conical groove that cooperates with the clamping sleeve. An annular connecting cavity is coaxially provided in the sealing spacer, and a pneumatic component is provided in the connecting cavity. The pneumatic component is used to drive the extrusion sleeve to move in the direction away from the sealing spacer, so that the inner wall of the conical groove generates an extrusion force on the outer wall of the clamping sleeve.

[0013] Through the above technical solution, the sealing sleeve slides on the periphery of the sealing spacer sleeve toward the clamping sleeve, so that the inner wall of the conical groove on the extrusion sleeve generates an extrusion force on the clamping sleeve, causing the clamping sleeve to produce an elastic contraction deformation along its radial inner side, thereby reducing the cable threading hole of the clamping sleeve and generating a clamping force on the sealing ring, so that the sealing ring can clamp the cable and make the contact surface between the cable and the sealing ring closer.

[0014] Furthermore, the pneumatic component includes a sliding plug that is coaxially slidably engaged in the connecting cavity, and the sliding plug separates the connecting cavity into two cavities that are not connected to each other. The two cavities are defined as a first cavity and a second cavity in the direction away from the fixed disk, and the wall surface of the sealing sleeve is provided with an air vent that passes through the second cavity. A plurality of push rods are fixedly connected to the end face of the sliding plug, and one end of the push rod that passes through the sealing sleeve is fixedly connected to the end face of the extrusion sleeve. A spacer ring is fixedly installed at the mouth of the second cavity, and the end face of the spacer ring is provided with a sliding hole for the push rod to pass freely.

[0015] Through the above technical solution, the gas in the air box enters the second cavity through the air vent and generates thrust on the sliding plug, so that the sliding plug overcomes the air pressure resistance in the first cavity and moves until it reaches a balanced state. When the air pressure in the air box drops, the air pressure in the first cavity is greater than the air pressure in the second cavity, so that the sliding plug moves away from the fixed disk, so that the sliding plug drives the push rod to move, and the push rod synchronously drives the extrusion sleeve to move, so that the inner wall of the conical groove on the extrusion sleeve slides relative to the outer wall of the clamping sleeve, and generates extrusion force on the periphery of the extrusion sleeve.

[0016] Furthermore, a spring is installed in the first cavity, and the spring elastically presses against the end surface of the sliding plug and gives the sliding plug potential energy to move in a direction away from the fixed disk.

[0017] Through the above technical solution, a spring is provided, which has an elastic resisting force on the sliding plug, so that when the air pressure in the air box drops, the sliding plug can move in time and cause the extrusion sleeve and the clamping sleeve to slide relative to each other.

[0018] Furthermore, an inward-turned flange is fixedly connected to one end of the clamping sleeve away from the cylindrical sleeve, and the flange is used to limit the movement of the sealing ring.

[0019] Through the above technical solution, the flange has a limiting effect on the movement of the sealing ring in the direction away from the fixed disk, thereby preventing the sealing ring from escaping from the cable threading hole and affecting the sealing effect of the sealing ring on the cable.

[0020] Furthermore, the air replenishing unit includes an air tank installed in the air box, and the air tank is located above the sealing sleeve. The wall of the air tank is provided with an air outlet seat, the inner cavity of the air outlet seat is connected with the inner cavity of the air tank, and a connecting component is provided in the air outlet seat. The connecting component is used to open the mouth of the air outlet seat when the sealing sleeve moves away from the sealing sleeve.

[0021] Through the above technical solution, when the air pressure in the air box drops, the sliding plug will move and the sealing sleeve will move. When the sealing sleeve moves, the connecting component will be triggered to connect the inner cavity of the air outlet seat and the air box. In this way, the insulating medium gas in the gas storage tank will enter the air box from the air outlet seat, thereby replenishing the gas in the air box, increasing the gas concentration, and reducing the phenomenon that the gas concentration in the air box decreases due to the decrease in air pressure, which affects the arc extinguishing.

[0022] Furthermore, the connecting component includes a fixed plug coaxially fixedly installed in the inner cavity of the air outlet seat, and a plurality of first connecting ports are provided on the end face of the fixed plug. A sealing piston is coaxially and slidingly installed in the inner cavity of the air outlet seat, and a second connecting port is provided on the end face of the sealing piston that is staggered with the first connecting port. The sealing piston is located above the fixed plug, and the abutting surfaces of the two end faces are in a sealed state after they abut each other. The sealing sleeve is provided with a driving structure for driving the sealing piston to move toward the fixed plug.

[0023] Through the above technical solution, when the sealing sleeve moves toward the clamping sleeve, the driving structure will drive the sealing piston to move upward, so that the sealing piston will be out of the state of abutting the end face of the fixed plug, and the gas in the gas storage tank can enter the air box through the second connecting port and the first connecting port in turn, so as to realize the gas replenishment operation in the air box.

[0024] Furthermore, the driving structure includes a floating rod coaxially fixedly installed on the end face of the sealing piston, the lower end of the floating rod slidably penetrates the fixed plug and is connected to a changing element, and the changing element is used to drive the floating rod to move vertically when the sealing sleeve moves horizontally.

[0025] Through the above technical solution, when the sealing sleeve moves toward the clamping sleeve, the direction-changing element drives the floating rod to move vertically, thereby causing the sealing piston and the fixing plug to break away from the state of end-face abutment.

[0026] Furthermore, the changing element includes a fixed rod vertically fixed to the periphery of the sealing sleeve, a sliding pin is horizontally fixedly passed through the upper end of the fixed rod, a floating plate is fixed to the lower end of the floating rod, a pull rod is vertically fixed through the floating plate, a connecting block is fixed to the lower end of the pull rod, the connecting block is provided with a waist-shaped hole for the sliding pin to pass freely, the length direction of the waist-shaped hole has an angle with the axial direction of the floating rod, the inner wall of the air box is connected to a fixed plate, and the floating rod is slidably passed through the fixed plate.

[0027] Through the above technical solution, when the sealing sleeve moves, the fixed rod will drive the sliding pin to move, so that the sliding pin slides in the waist-shaped hole. The sliding pin slides from the upper end to the lower end of the waist-shaped hole, and then drives the connecting block to move upward, so that the sealing piston is out of the state of abutting the end face of the fixed plug.

[0028] Furthermore, a fixing frame is fixedly connected to the middle of the top of the floating plate, and the lower end of the floating rod is fixedly connected to the fixing frame.

[0029] Through the above technical solution, the fixed frame is located in the middle of the floating plate, so that the floating rod is subjected to more uniform force, avoiding the floating plate from tilting due to the difference in the upward movement stroke when multiple connecting blocks move upward, and then causing uneven force on the floating rod, thereby affecting the floating rod driving the sealing piston to move upward.

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) In the present invention, the cable hole and the outer wall of the cable are in a sealed state. When the gas pressure in the gas box drops, the contraction unit will be triggered and drive the clamping sleeve to produce elastic contraction deformation, thereby clamping the sealing ring of the cable hole wall, making the sealing ring and the surface contact of the cable closer, and the deformation seam is also closed, thereby reducing the leakage between the cable and the cable hole. In addition, when the gas pressure in the gas box drops, the gas replenishing unit will be activated, thereby replenishing gas into the gas box, increasing the gas pressure in the gas box, thereby maintaining the positive pressure state in the gas box in a short time, and increasing the concentration of the insulating gas medium in the gas box to prevent a significant impact on the arc extinguishing of the gas box, and giving the operation and maintenance personnel enough time to reach the site for operation and maintenance. In addition, under normal use, the clamping force of the clamping sleeve on the sealing ring is small, thereby preventing the sealing ring from being deformed by clamping the cable for a long time, affecting the sealing effect of the sealing ring on the cable;

[0032] (2) In the present invention, the gas in the air box enters the second cavity through the air vent and generates a thrust on the sliding plug, causing the sliding plug to overcome the air pressure resistance in the first cavity and move until it reaches a balanced state. When the air pressure in the air box drops, the air pressure in the first cavity is greater than the air pressure in the second cavity, causing the sliding plug to move away from the fixed disk, causing the sliding plug to drive the push rod to move, and the push rod synchronously drives the extrusion sleeve to move, causing the inner wall of the conical groove on the extrusion sleeve to slide relative to the outer wall of the clamping sleeve, and generating an extrusion force on the periphery of the extrusion sleeve;

[0033] (3) In the present invention, when the gas pressure in the gas box drops, the sliding plug will move, and the sealing sleeve will move. When the sealing sleeve moves, the connecting component will be triggered to connect the inner cavity of the gas outlet seat and the gas box. In this way, the insulating medium gas in the gas storage tank will enter the gas box from the gas outlet seat, thereby replenishing the gas in the gas box, increasing the gas concentration, and reducing the phenomenon that the gas concentration in the gas box decreases due to the decrease in gas pressure, which affects the arc extinction.

[0034] (4) In the present invention, the fixing frame is located in the middle of the floating plate, so that the floating rod is subjected to a more uniform force, thereby preventing the floating plate from tilting due to the difference in the upward movement stroke when multiple connecting blocks move upward, thereby causing the floating rod to be subjected to uneven force, thereby affecting the floating rod driving the sealing piston to move upward. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the overall structure of a switch cabinet using clean air as the insulating medium in the present invention;

[0036] Figure 2 This is a schematic diagram of the positional relationship between the sealing spacer and the gas storage tank after assembly in the present invention;

[0037] Figure 3 yes Figure 2 A magnified schematic diagram of the local structure at point A;

[0038] Figure 4 yes Figure 2 A schematic diagram of the positional relationship from another perspective;

[0039] Figure 5 yes Figure 4 Schematic diagram of the exploded structure;

[0040] Figure 6 yes Figure 5 A magnified schematic diagram of the local structure at point B in the middle;

[0041] Figure 7 This is a schematic diagram of the positional relationship among the fixed disk, the sealing spacer, and the sealing sliding sleeve after assembly in the present invention;

[0042] Figure 8 yes Figure 7 Schematic diagram of the positional relationship after the middle part of the structure is cut open;

[0043] Figure 9 yes Figure 7 Schematic diagram of the exploded structure;

[0044] Figure 10 It is a schematic diagram of the positional relationship between the cylindrical sleeve and the clamping sleeve after assembly in the present invention.

[0045] Figure numerals: 1. cabinet; 2. air box; 3. fixed plate; 4. sealing spacer; 5. floating plate; 6. fixed plate; 7. air outlet seat; 8. air storage tank; 9. extrusion sleeve; 10. sealing ring; 11. flange; 12. deformation joint; 13. push rod; 14. cylindrical sleeve; 15. air vent; 16. sliding pin; 17. waist-shaped hole; 18. pull rod; 19. connecting block; 20. fixing rod; 21. cable hole; 22. sealing sleeve; 23. floating rod; 24. spring; 25. spacer ring; 26. sliding plug; 27. sealing piston; 28. second connecting port; 29. ​​fixing plug; 30. first connecting port; 31. fixing frame; 32. tubular portion; 33. conical groove; 34. connecting cavity; 35. sealing ring mounting groove; 36. clamping sleeve. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] like Figures 1-10As shown, this embodiment provides: a switch cabinet with clean air as the insulating medium, including a switch cabinet cabinet body 1 and an air box 2 installed in the cabinet body 1, the air box 2 shell is provided with a plurality of cable through-holes, and a sealing spacer 4 is tightly inserted into the cable through-holes, and the sealing spacer 4 is coaxially fixed to one end of the sealing spacer 4 passing through the air box 2 shell. The fixing plate 3 is fixed to the air box 2 shell by screws or rivets. It should be noted that the threads or rivets cannot penetrate the air box 2 shell to avoid leakage. The fixing plate 3 and the sealing A cable hole 21 in the form of a through hole is formed on the end face of the spacer 4. The diameter of the cable hole 21 matches the diameter of the cable of the electrical equipment in the air box 2. The cable of the electrical equipment in the air box 2 passes through the cable hole 21 to the outside of the air box 2 and is connected to the external electrical equipment. In addition, a rubber layer can be provided on the hole wall of the cable hole 21 to increase the sealing degree between the cable and the wall of the cable hole 21. An annular communication cavity 34 is coaxially formed on the end face of the end of the sealing spacer 4 that penetrates into the air box 2, and a tubular portion 32 is formed on the inner side of the sealing spacer 4.

[0048] The end face of one end of the sealing spacer 4 that penetrates into the air box 2 is coaxially fixed with a cylindrical sleeve 14, and the end of the cylindrical sleeve 14 away from the sealing spacer 4 is coaxially fixed with a clamping sleeve 36, the outer diameter of the clamping sleeve 36 increases successively in the direction away from the sealing spacer 4, and the clamping sleeve 36 is provided with a cable threading hole that passes through the cylindrical sleeve 14, and a plurality of deformation gaps 12 that are connected to the cable threading holes are provided on the periphery of the clamping sleeve 36. A sealing ring mounting groove 35 is coaxially provided in the clamping sleeve 36, and a sealing ring 10 is mounted in the sealing ring mounting groove 35. The inner diameter of the sealing ring 10 matches the outer diameter of the cable. In addition, the end of the clamping sleeve 36 away from the cylindrical sleeve 14 is fixed with an inverted flange 11, which is used to limit the movement of the sealing ring 10. The flange 11 has a limiting effect on the movement of the sealing ring 10 in the direction away from the fixed plate 3, thereby preventing the sealing ring 10 from escaping from the cable threading hole, thereby affecting the sealing effect of the sealing ring 10 on the cable;

[0049] The cylindrical sleeve 14 is slidably covered with a sealing sleeve 22 on its periphery. The sealing sleeve 22 is coaxially fixed with an extrusion sleeve 9 at one end away from the sealing spacer 4. The extrusion sleeve 9 is coaxially provided with a conical groove 33 that cooperates with the clamping sleeve 36. An annular connecting cavity 34 is coaxially provided in the sealing spacer 4. A sliding plug 26 is coaxially slidably installed in the connecting cavity 34. The sliding plug 26 separates the connecting cavity 34 into two cavities that are not connected to each other. The two cavities are defined as the first cavity and the second cavity in the direction away from the fixed disk 3. The wall surface of the sealing spacer 4 is provided with an air vent 15 that passes through the second cavity. A plurality of push rods 13 are fixed to the end face of the sliding plug 26. One end of the push rod 13 that passes through the sealing spacer 4 is fixed to the end face of the extrusion sleeve 9. A spacer ring 25 is fixedly installed at the mouth of the second cavity. The end face of the spacer ring 25 is provided with a sliding hole for the push rod 13 to pass freely. The gas in the air box 2 enters the second cavity through the air vent 15 and presses the sliding plug 26. The thrust is generated, so that the sliding plug 26 overcomes the air pressure resistance in the first cavity and moves until it reaches a balanced state. When the air pressure in the air box 2 drops, the air pressure in the first cavity is greater than the air pressure in the second cavity, thereby causing the sliding plug 26 to move in the direction away from the fixed disk 3, so that the sliding plug 26 drives the push rod 13 to move, and the push rod 13 synchronously drives the extrusion sleeve 9 to move, so that the inner wall of the conical groove 33 on the extrusion sleeve 9 slides relative to the outer wall of the clamping sleeve 36, and generates an extrusion pressure on the periphery of the clamping sleeve 36. In addition, a spring 24 is installed in the first cavity, and the spring 24 elastically presses against the end face of the sliding plug 26 and gives the sliding plug 26 potential energy to move in the direction away from the fixed disk 3. The spring 24 has an elastic pressing force on the sliding plug 26, so that when the air pressure in the air box 2 drops, the sliding plug 26 can move in time, and cause the extrusion sleeve 9 and the clamping sleeve 36 to slide relative to each other.

[0050] A horizontal gas storage tank 8 is installed in the air box 2 through a bracket, and the gas storage tank 8 is located above the sealing spacer 4. An air outlet seat 7 is provided on the wall of the gas storage tank 8. The inner cavity of the gas outlet seat 7 is connected with the inner cavity of the gas storage tank 8. A fixed plug 29 is coaxially fixedly installed in the inner cavity of the gas outlet seat 7, and the periphery of the fixed plug 29 and the inner cavity wall of the gas outlet seat 7 are in a sealed state. A plurality of first communication ports 30 are provided on the end face of the fixed plug 29. A sealing piston 27 is coaxially and slidably installed in the inner cavity of the gas outlet seat 7. A second communication port 28 is provided on the end face of the sealing piston 27, which is staggered with the first communication port 30. The sealing piston 27 is located above the fixed plug 29, and the abutting surface of the two end faces after they abut against each other is in a sealed state. A floating rod 23 is coaxially and fixedly penetrated by the end face of the sealing piston 27. The fixed rod 20 is vertically fixedly connected to the periphery of the sealing sleeve 22. A sliding pin 16 is fixedly penetrated horizontally on the upper end of the fixed rod 20, and a floating The plate 5 and the floating plate 5 are vertically fixed with a pull rod 18, and the lower end of the pull rod 18 is fixedly connected to a connecting block 19. The connecting block 19 is provided with a waist-shaped hole 17 for the sliding pin 16 to pass freely. The length direction of the waist-shaped hole 17 has an included angle with the axial direction of the floating rod 23. The inner wall of the air box 2 is connected with a fixed plate 6, and the floating rod 23 is slidably penetrated by the fixed plate 6. When the sealing sleeve 22 moves, the fixed rod 20 drives the sliding pin 16 to move, so that the sliding pin 16 slides in the waist-shaped hole 17. The sliding pin 16 slides from the upper end of the waist-shaped hole 17 to the lower end, and then drives the connecting block 19 to move upward, so that the sealing piston 27 is out of the state of abutting the end surface of the fixed plug 29, so that the gas in the gas storage tank 8 can enter the air box 2 through the second connecting port 28 on the sealing piston 27 and the first connecting port 30 on the fixed plug 29 in sequence to replenish the gas in the air box 2;

[0051] When the air pressure in the air box 2 is restored, the sliding plug 26 will move in the opposite direction, causing the sealing sleeve 22 to move in the opposite direction, and causing the sliding pin 16 to slide from the lower end of the waist-shaped hole 17 to the upper end of the waist-shaped hole 17, thereby driving the sealing piston 27 to move downward, so that the end face of the sealing piston 27 and the end face of the fixed plug 29 are butted against each other. Since the first connecting port 30 on the end face of the fixed plug 29 and the second connecting port 28 on the end face of the sealing piston 27 are in an open distribution state, the abutting surfaces of the end faces of the fixed plug 29 and the sealing piston 27 when they abut against each other are in a sealed state, and the gas in the air storage tank 8 will not continue to Continuing to enter the air box 2, in this embodiment, the gas pressure in the air storage tank 8 is consistent with the air pressure in the air box 2 under normal working conditions, or slightly greater than the air pressure in the air box 2. In addition, a fixing frame 31 is fixedly connected to the middle of the top of the floating plate 5, and the lower end of the floating rod 23 is fixed to the fixing frame 31. The fixing frame 31 is located in the middle of the floating plate 5, so that the floating rod 23 is subjected to more uniform force, avoiding the floating plate 5 from tilting due to the difference in the upward movement stroke when multiple connecting blocks 19 move upward, and then causing the floating rod 23 to be subjected to uneven force, thereby affecting the floating rod 23 driving the sealing piston 27 to move upward.

[0052] The working principle of this embodiment is as follows:

[0053] When the gas pressure in the gas box 2 drops, the outside air will enter the gas box 2 from the leakage point, and the concentration of the specific gas (such as SF6 gas) in the gas box 2 may be reduced, affecting the arc extinguishing effect. The leakage point is most likely to be the connection between the cable and the gas box 2. Therefore, the connection between the cable and the gas box 2 needs to be tightly connected. That is, when the pressure in the gas box 2 drops to a certain level, the spring 24 and the gas in the first cavity act together on the end face of the sliding plug 26, causing the sliding plug 26 to move away from the fixed disk 3. When the sliding plug 26 moves, it will drive the push rod 13 to move, and the push rod 13 will synchronously drive the extrusion sleeve 9 to move, so that the conical groove 3 on the extrusion sleeve 9 is closed. The inner wall of the clamping sleeve 36 slides relative to the outer wall of the clamping sleeve 36, and generates an extrusion force on the periphery of the clamping sleeve 36, so that the clamping sleeve 36 is subjected to the extrusion force along its inner side, thereby generating elastic contraction deformation, so that the hole wall of the cable hole clamps the sealing ring 10, so that the sealing ring 10 and the surface of the cable are in closer contact, and the deformation joint 12 is also closed, thereby reducing the leakage between the cable and the cable hole 21. In addition, the sealing sleeve 22 can block the portion where the deformation joint 12 extends to the cylindrical sleeve 14, preventing the air in the air box 2 from entering the cable hole 21 from the portion where the deformation joint 12 extends to the cylindrical sleeve 14. In this way, the leakage between the cable and the cable hole 21 can be improved.

[0054] In addition, when the sealing sleeve 22 moves, the fixed rod 20 drives the sliding pin 16 to move, so that the sliding pin 16 slides in the waist-shaped hole 17. The sliding pin 16 slides from the upper end of the waist-shaped hole 17 to the lower end, thereby driving the connecting block 19 to move upward, so that the sealing piston 27 is released from the state of abutting against the end surface of the fixed plug 29, thereby allowing the gas in the gas storage tank 8 (mainly SF6 gas) to enter the gas box 2 through the second connecting port 28 on the sealing piston 27 and the first connecting port 30 on the fixed plug 29 in sequence, so as to replenish the gas in the gas box 2;

[0055] When the gas in the gas box 2 is replenished into the gas box 2, the air pressure in the gas box 2 will gradually increase until it is close to the air pressure during normal operation. Since specific gas is replenished into the gas box 2, the gas concentration in the gas box 2 increases, reducing the impact on the arc extinguishing effect. In addition, when the air pressure in the gas box 2 is restored, the sliding plug 26 will move in the opposite direction, causing the sealing sleeve 22 to move in the opposite direction, and causing the sliding pin 16 to slide from the lower end of the waist-shaped hole 17 to the upper end of the waist-shaped hole 17, thereby driving the sealing piston 27 to move downward, so that the end face of the sealing piston 27 and the end face of the fixed plug 29 are butted against each other. Since the first connecting port 30 on the end face of the fixed plug 29 and the second connecting port 28 on the end face of the sealing piston 27 are in an open distribution state, the abutting surfaces when the end face of the fixed plug 29 and the end face of the sealing piston 27 are butted against each other are in a sealed state, and the gas in the gas storage tank 8 will not continue to enter the gas box 2.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A switch cabinet using clean air as an insulating medium, comprising a switch cabinet body (1) and an air box (2) installed in the cabinet body (1), wherein the outer shell of the air box (2) is provided with a plurality of cable through-holes, characterized in that: Also includes: A fixed plate (3) is mounted on the outer shell of the gas box (2), and a sealing sleeve (4) is fixedly connected to the end surface thereof and inserted into the cable through-hole. The sealing sleeve (4) is provided with a cable hole (21); A cylindrical sleeve (14) is coaxially fixed to one end of the sealing sleeve (4) passing through the air box (2), and a clamping sleeve (36) is coaxially fixed to the end away from the sealing sleeve (4). The clamping sleeve (36) is provided with a cable threading hole passing through the cylindrical sleeve (14). The clamping sleeve (36) is provided with a plurality of deformation seams (12) communicating with the cable threading holes on its periphery. A sealing ring installation groove (35) is coaxially provided in the clamping sleeve (36), and a sealing ring (10) is installed in the sealing ring installation groove (35). A contraction unit is provided in the sealing spacer (4) and is used to drive the clamping sleeve (36) to contract when the pressure inside the air box (2) is lost; an air supply unit is provided in the air box (2) and is used to supply air to the inside of the air box (2) when the clamping sleeve (36) contracts; The shrinkage unit comprises a sealing sleeve (22) which is slidably mounted on the periphery of the cylindrical sleeve (14); an end of the sealing sleeve (22) which is away from the sealing sleeve (4) is coaxially fixed with an extrusion sleeve (9); the outer diameter of the clamping sleeve (36) increases in sequence in a direction away from the sealing sleeve (4); the extrusion sleeve (9) is coaxially provided with a conical groove (33) which cooperates with the clamping sleeve (36); an annular connecting cavity (34) is coaxially provided in the sealing sleeve (4); a pneumatic component is provided in the connecting cavity (34); the pneumatic component is used to drive the extrusion sleeve (9) to move in a direction away from the sealing sleeve (4), so that the inner wall of the conical groove (33) generates an extrusion force on the outer wall of the clamping sleeve (36); The pneumatic assembly includes a sliding plug (26) coaxially slidingly engaged in the connecting cavity (34), the sliding plug (26) divides the connecting cavity (34) into two mutually unconnected cavities, the two cavities being defined as a first cavity and a second cavity in the direction away from the fixed disk (3), the wall of the sealing sleeve (4) is provided with an air vent (15) penetrating the second cavity, the end face of the sliding plug (26) is fixedly connected to a plurality of push rods (13), one end of the push rod (13) passing through the sealing sleeve (4) is fixedly connected to the end face of the extrusion sleeve (9), the mouth of the second cavity is fixedly mounted with a spacer ring (25), the end face of the spacer ring (25) is provided with a sliding hole for the push rod (13) to pass freely; A spring (24) is installed in the first cavity, and the spring (24) elastically presses against the end surface of the sliding plug (26) and imparts potential energy to the sliding plug (26) to move in a direction away from the fixed disk (3).

2. The switch cabinet with clean air as the insulating medium according to claim 1, characterized in that: An inward-turned flange (11) is fixedly connected to one end of the clamping sleeve (36) away from the cylindrical sleeve (14), and the flange (11) is used to limit the movement of the sealing ring (10).

3. The switch cabinet using clean air as the insulating medium according to claim 1, characterized in that: The air supply unit includes an air storage tank (8) installed in the air box (2), and the air storage tank (8) is located above the sealing spacer (4). The wall of the air storage tank (8) is provided with an air outlet seat (7), the inner cavity of the air outlet seat (7) is connected with the inner cavity of the air storage tank (8), and a connecting component is provided in the air outlet seat (7). The connecting component is used to open the mouth of the air outlet seat (7) when the sealing sleeve (22) moves in a direction away from the sealing spacer (4).

4. The switch cabinet using clean air as the insulating medium according to claim 3, characterized in that: The connecting component comprises a fixed plug (29) coaxially fixedly mounted on the inner cavity of the gas outlet seat (7), a plurality of first connecting ports (30) being provided on the end face of the fixed plug (29), a sealing piston (27) being coaxially slidably mounted on the inner cavity of the gas outlet seat (7), a second connecting port (28) being staggered with the first connecting port (30) being provided on the end face of the sealing piston (27), the sealing piston (27) being located above the fixed plug (29), and the abutting surfaces of the two end faces being in a sealed state after abutting each other, and the sealing sleeve (22) being provided with a driving structure for driving the sealing piston (27) to move toward the fixed plug (29).

5. The switch cabinet using clean air as the insulating medium according to claim 4, characterized in that: The driving structure includes a floating rod (23) coaxially fixedly arranged on the end surface of the sealing piston (27), the lower end of the floating rod (23) slidingly penetrates the fixed plug (29) and is connected to a changing element, and the changing element is used to drive the floating rod (23) to move vertically when the sealing sleeve (22) moves horizontally.

6. The switch cabinet using clean air as the insulating medium according to claim 5, characterized in that: The deflection element includes a fixed rod (20) vertically fixed to the periphery of the sealing sleeve (22), a sliding pin (16) is horizontally fixedly passed through the upper end of the fixed rod (20), a floating plate (5) is fixedly connected to the lower end of the floating rod (23), a pull rod (18) is vertically fixedly passed through the floating plate (5), a connecting block (19) is fixedly connected to the lower end of the pull rod (18), and a waist-shaped hole (17) is opened in the connecting block (19) for the sliding pin (16) to pass freely, and the waist-shaped hole (17) has an angle with the axial direction of the floating rod (23) in its length direction, and the inner wall of the air box (2) is connected to a fixed plate (6), and the floating rod (23) is slidably passed through the fixed plate (6).

7. The switch cabinet using clean air as the insulating medium according to claim 6, characterized in that: A fixing frame (31) is fixedly connected to the middle of the top of the floating plate (5), and the lower end of the floating rod (23) is fixedly connected to the fixing frame (31).

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