An integrated pole-mounted vacuum circuit breaker

Abstract

This invention relates to the field of circuit breaker technology, specifically to an integrated pole-mounted vacuum circuit breaker, comprising a mechanism box and three insulating poles. A vacuum interrupter is coaxially arranged within each insulating pole, with a stationary contact and a moving contact respectively located at the upper and lower ends of the vacuum interrupter. The upper end of the stationary contact extends to the upper side of the insulating pole. The three insulating poles are fixedly connected to the upper end of the mechanism box by bolts. This invention integrates the vacuum interrupter, the isolation break assembly, and the current transformer coaxially within the same insulating pole, eliminating the need for mounting brackets and lateral arrangement space required for external disconnect switches in traditional structures. This results in a more compact overall structure, reducing the space occupied by the pole crossarm. Simultaneously, the center of gravity of the entire unit remains on the vertical central axis of the mechanism box, preventing offset torque and significantly reducing the long-term load on the crossarm and pole, thus improving the structural stability after installation and operation.

Description

Technical Field

[0001] This invention relates to the field of circuit breaker technology, specifically to an integrated pole-mounted vacuum circuit breaker. Background Technology

[0002] In power distribution systems, pole-mounted vacuum circuit breakers are core equipment for ensuring the safe operation of power lines. Traditional pole-mounted vacuum circuit breakers mostly adopt a separate external structure, meaning the circuit breaker body and the disconnecting switch are two independent physical units, fixed to the crossarm of the utility pole by a support bracket. During operation, the vacuum interrupter chamber inside the circuit breaker body is responsible for breaking the current and extinguishing the arc, while the disconnecting switch provides a visible disconnection gap through its air-exposed contact blade structure to meet the safety regulations for power maintenance.

[0003] However, traditional pole-mounted vacuum circuit breakers, due to the horizontal or oblique arrangement of the circuit breaker poles and isolating contacts, result in an excessively large envelope diameter on the utility pole. This not only increases installation difficulty but also, because the center of gravity is biased towards the circuit breaker side, places a huge torque load on the supporting crossarm, posing a safety hazard under strong winds or earthquake conditions. Furthermore, existing circuit breakers and disconnectors are linked through complex external linkage mechanisms. Due to the long transmission chain, during long-term outdoor operation, the linkage is susceptible to environmental corrosion, leading to mechanical jamming or play. This makes it difficult to guarantee the stringent "break first, then isolate" closing and opening sequence, easily causing serious accidents such as opening and closing the disconnector under load. In addition, the disconnector contacts are exposed to the natural environment for extended periods. In salt spray, humid, or highly polluted areas, oxide layers or scale easily form on the contact surface, leading to increased contact resistance, abnormal temperature rise, and even flashover accidents.

[0004] Therefore, designing an integrated pole-mounted vacuum circuit breaker with a compact structure and simplified transmission chain has become a pressing technical challenge in the field of power switchgear. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated pole-mounted vacuum circuit breaker to solve the problems of large size, off-center center of gravity, long transmission chain, and susceptibility to environmental corrosion and jamming caused by the separate external structure of the pole-mounted circuit breaker and disconnecting switch in the prior art, as well as the long-term exposure of the disconnecting break leading to a decrease in external insulation performance and an increase in contact resistance.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An integrated pole-mounted vacuum circuit breaker includes a mechanism box and three insulating poles. A vacuum interrupter is coaxially arranged within each insulating pole. A stationary contact and a moving contact are respectively located at the upper and lower ends of each vacuum interrupter. The upper end of the stationary contact extends to the upper side of the insulating pole. The three insulating poles are fixedly connected to the upper end of the mechanism box by bolts. An insulating rod, an isolation break assembly, and a current transformer are coaxially arranged from bottom to top within each insulating pole. The lower end of the insulating rod extends into the mechanism box, and the insulating rod is slidably connected to the mechanism box. The mechanism box is used to drive the insulating rod to move vertically. The isolation break assembly is fixedly installed at the upper end of the insulating rod, the current transformer is fixedly installed inside the insulating pole, and the moving contact completely penetrates to the lower side of the current transformer. The moving contact is slidably connected to the isolation break assembly. A terminal block is fixedly installed on the side wall of the insulating pole, and the terminal block extends to the inner side of the insulating pole. When the insulating rod is at the lower stop point, the vertical distance between the isolation break assembly and the lower end face of the terminal block is L1, and the vertical distance between the moving contact and the stationary contact is L2. 12mm≤L1≤18mm, 22mm≤L2≤28mm.

[0007] By placing the isolation break assembly and current transformer inside the insulating pole and coaxially arranging them on the same vertical axis as the vacuum interrupter, the installation bracket and lateral arrangement space of the external disconnect switch in the traditional structure are eliminated. The three insulating poles are arranged vertically only at the top of the mechanism box, which not only occupies less space on the crossarm of the utility pole during installation and reduces the probability of spatial interference with other equipment under complex wiring conditions, but also concentrates the center of gravity of the whole machine on the vertical central axis of the mechanism box, without generating additional offset torque, greatly reducing the load on the crossarm and utility pole, and improving the structural stability of the whole machine in long-term operation.

[0008] Furthermore, by driving the insulating rod vertically through the same mechanism box, the opening and closing operations of the vacuum interrupter and the isolation break can be completed simultaneously. Compared with the traditional external linkage structure, the transmission chain is significantly shortened, which not only reduces the play and corrosion risk of the moving joints, but also accurately ensures the timing requirement of "vacuum interrupter first disconnects, then isolation break separates" when opening the circuit breaker, and the action logic of "isolation break connects first, then vacuum interrupter closes" when closing the circuit breaker. This fundamentally avoids the serious operational accidents of opening and closing the isolation break under load. When performing the opening action, the insulating rod moves from the upper stop point to the lower stop point. Since 12mm≤L1≤18mm and 22mm≤L2≤28mm, the moving contact and stationary contact in the vacuum arc-extinguishing chamber disconnect first to complete the arc extinguishing. Then, the isolation break assembly reaches the lower stop point and separates from the terminal. When performing the closing action, the insulating rod moves upward from the lower stop point. The isolation break assembly contacts the terminal first to complete the conduction. Then, the moving contact moves upward and closes with the stationary contact to connect the main circuit. This ensures the stability of the closing action sequence and does not increase the overall height of the insulating pole too much, thus balancing operational safety and the compactness of the overall structure.

[0009] Furthermore, the isolation break assembly is completely enclosed inside the insulating pole, preventing direct contact with outdoor rainwater, salt spray, and dirt. This avoids increased contact resistance due to oxidation and scale buildup on the contact surface, and also prevents external insulation flashover, significantly improving operational reliability in highly polluted and humid areas.

[0010] Preferably, the isolation break assembly includes a first mounting base, a second mounting base, a first spring, a contact piece, a limiting seat, and a second spring. The first mounting base is coaxially fixedly connected to the upper end of the insulating rod. The first spring is coaxially fixedly connected to the upper end of the first mounting base. The second mounting base is fixedly connected to the upper end of the first spring. The contact piece is coaxially fixedly connected to the upper end of the second mounting base. The limiting seat is coaxially fixedly connected to the lower end of the moving contact and is located between the first and second mounting bases. The second spring is coaxially fixedly connected to the lower end of the limiting seat and is fixedly connected to the first mounting base. The contact piece is slidably connected to the side wall of the moving contact.

[0011] By configuring the isolation break assembly as described above, during the closing process of the insulating rod moving upward from the lower stop point, the insulating rod first drives the No. 1 mounting base to move upward synchronously. The No. 1 spring will first push the No. 2 mounting base and the contact piece upward, so that the contact piece contacts the terminal first, completing the conduction between the contact piece and the terminal. When the No. 1 mounting base continues to move upward, the No. 1 spring will be gradually compressed, and then the stationary contact and the moving contact will contact to complete the closing. At this time, the preload of the No. 1 spring will continuously ensure the pressure between the contact piece and the terminal is stable, avoiding the problem of loose contact after long-term operation. When the circuit breaker is tripped, the insulating rod drives the No. 1 mounting base downwards. The No. 2 spring releases its elastic force first. After the No. 2 spring has fully released its elastic force, it pulls down the limit seat to ensure that the moving contact and the stationary contact separate first to extinguish the arc. At this time, the contact piece remains in a conductive state with the terminal block until the No. 1 mounting base continues to move downwards to its final position. Only then will the contact piece disengage from the terminal block, completely disconnecting the isolation break. This meets the "break first, then open; close first, then shut" operation sequence requirements. The entire process does not require additional linkage transmission and can be achieved solely by the movement of the internal spring and the insulating rod, making the structure simple and reliable.

[0012] Preferably, the second mounting base is provided with multiple contact pieces, each contact piece including a connecting part and a sliding part. The connecting part is fixedly connected to the second mounting base, and the sliding part is slidably connected to the side wall of the moving contact. The outer side wall of the contact piece is provided with a slanted coil spring, which is sleeved on the outer side wall of the multiple sliding parts. The slanted coil spring is used to provide pressure to the multiple sliding parts toward the moving contact.

[0013] By setting the contact piece to a multi-lobed structure and using a slanted coil spring to apply force, multiple sliding parts are always evenly attached to the side wall of the moving contact under the encircling pressure of the slanted coil spring. This ensures that the isolation break assembly maintains good conductive contact as it slides up and down along the moving contact with the insulating rod, preventing problems such as incomplete connection or arcing. At the same time, the slanted coil spring itself has good deformation compensation capability. Even if the sliding parts experience slight wear after long-term use, the slanted coil spring can automatically shrink to compensate for the gap, preventing a decrease in contact pressure due to wear and effectively extending the overall service life of the equipment.

[0014] Preferably, one end of the terminal block extending into the insulating pole is provided with a through hole that passes through both the upper and lower sides. The moving contact is coaxially arranged with the through hole. A deformation part is provided between the connecting part and the sliding part. The deformation part is C-shaped with its opening facing the moving contact, and the maximum outer diameter of the deformation part is 0.5 to 1.5 mm larger than the inner diameter of the through hole.

[0015] By setting a C-shaped deformation part between the connecting part and the sliding part, and setting a through hole on the terminal, with the deformation part and the through hole having an interference fit size of 0.5 to 1.5 mm, sufficient contact pressure can be ensured without causing excessive compressive stress on the deformation part, which would lead to plastic deformation that cannot be reset. This balances contact reliability and structural elasticity. When the contact piece moves upward and passes through the through hole of the terminal, the C-shaped deformation part will be squeezed inward by the inner wall of the through hole, thereby ensuring the connection stability between the sliding part and the moving contact. Furthermore, the outer wall of the deformation part fits against the inner wall of the through hole, realizing dual contact conductivity between the terminal and the contact piece. One path is radial contact between the sliding part and the inner wall of the through hole, and the other path is end face contact between the connecting part and the lower end face of the terminal. This significantly reduces contact resistance, improves the current carrying capacity under high current conditions, and avoids the problem of excessive temperature rise caused by oxidation and loosening of a single contact point during long-term operation.

[0016] Preferably, the end of the connecting part near the moving contact is fixedly connected to the second mounting base, while the end away from the moving contact is in a free state. The middle part of the connecting part is provided with an upwardly protruding arc-shaped protrusion, the height of which is 2-5mm.

[0017] By setting an upward-protruding arc-shaped protrusion in the middle of the connecting part, when the contact piece moves upward into place and the connecting part abuts against the lower end face of the terminal, the arc-shaped protrusion will be squeezed and generate elastic deformation. This deformation will provide stable contact pressure between the connecting part and the terminal, avoiding the problem of poor local contact due to machining flatness error of the end face of the connecting part. At the same time, the protrusion height of 2-5mm can provide sufficient deformation allowance to compensate for machining error, and will not reduce the overall rigidity of the connecting part too much, avoiding irreversible plastic deformation after long-term pressure.

[0018] Preferably, a sleeve is coaxially disposed inside the insulating pole, and the sleeve is fixedly connected to the inner side wall of the insulating pole. A guide groove is formed on the inner wall of the sleeve, and the guide groove includes a straight section and an inclined section. The straight section passes through the lower end of the sleeve, and the inclined section passes through the upper side of the sleeve. A guide pin is fixedly disposed on the outer side wall of the second mounting base. When the insulating rod is located at the lower stop point, the guide pin is disposed in the guide groove, and the height of the straight section is less than L1.

[0019] By installing a sleeve with an internal guide groove inside the insulating pole and a guide pin on the outer wall of the No. 2 mounting base, when the circuit is closed, the insulating rod drives the No. 2 mounting base to move upward. The guide pin slides along the contour of the guide groove. When the guide pin enters the inclined section, the No. 2 mounting base is driven to rotate by the guide groove, causing multiple contact pieces to rotate synchronously. This allows the deformed part to rub against the inner wall of the through hole during rotation, effectively scraping away dust, oxide debris, and other impurities that may be attached to the outer side of the deformed part and the inner wall of the through hole. This prevents impurities from accumulating and increasing the contact resistance, ensuring a clean and good conductive contact surface every time the circuit is closed. Furthermore, since the height of the straight section is less than L1, the contact between the arc-shaped protrusion and the terminal occurs after the No. 2 mounting base rotates. The rotation process causes relative grinding between the arc-shaped protrusion and the lower end face of the terminal, eliminating the oxide layer and impurities on the lower end face of the terminal, further improving contact reliability. Moreover, with the straight section height less than L1, when the guide pin enters the inclined section and starts to drive the No. 2 mounting base to rotate, the isolation break has already completed the initial contact with the terminal block. The rotation will not affect the initial conduction sequence. The entire scraping and cleaning process is completed during the contact process, which not only ensures the reliability of the contact but also eliminates the need for additional cleaning structures, further simplifying the internal structure.

[0020] Preferably, a heat-conducting layer is provided between the current transformer and the inner wall of the insulating pole, the outer wall of the heat-conducting layer is fixedly connected to the inner wall of the insulating pole, and the inner wall of the heat-conducting layer is fixedly connected to the outer wall of the current transformer.

[0021] By setting a heat-conducting layer between the current transformer and the insulating pole, the heat generated by the current transformer during equipment operation can be quickly conducted to the outer wall of the insulating pole through the heat-conducting layer, and then diffused into the surrounding air. This avoids the problem of accelerated core aging and decreased insulation performance caused by the current transformer working in a high-temperature environment for a long time. It effectively improves the measurement accuracy and service life of the current transformer, and also avoids the aging effect of overheating on the insulation material of the inner wall of the insulating pole, further improving the long-term stability of the equipment.

[0022] Preferably, a Y-shaped sealing ring is provided at the sliding connection between the insulating rod and the mechanism box, and the lip of the Y-shaped sealing ring faces downward.

[0023] By setting a Y-shaped sealing ring with its lip facing downwards at the connection between the insulating pole and the mechanism box, humid air is blocked from entering the mechanism box through the sliding gap of the insulating rod. This avoids the problem of dust contamination and rainwater corrosion of the transmission components inside the mechanism box, extending the service life of the internal transmission structure. With the lip of the Y-shaped sealing ring facing downwards, the lip of the Y-shaped sealing ring deforms when the insulating rod moves downwards, reducing the resistance of the Y-shaped sealing ring to the insulating rod. This reduces the friction that the mechanism box drive motor needs to overcome during the opening operation, making the action response faster. When the insulating rod moves upwards, the air pressure in the mechanism cavity will compress the lip of the Y-shaped sealing ring to press tightly against the side wall of the insulating rod. The greater the air pressure, the tighter the seal, further improving the waterproof sealing effect and preventing moisture intrusion.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention integrates the vacuum interrupter, the isolation break assembly, and the current transformer coaxially within the same insulating pole, eliminating the need for mounting brackets and lateral arrangement space required for external disconnect switches in traditional structures. This results in a more compact overall structure, reducing the space occupied by the crossarm of the utility pole. Simultaneously, the center of gravity of the entire machine remains on the vertical central axis of the mechanism box, preventing the generation of offset torque. This significantly reduces the long-term load on the crossarm and utility pole, and improves the structural stability of the equipment after installation and operation.

[0025] 2. This invention utilizes a C-shaped deformation section between the connecting and sliding portions of the contact piece. The elastic deformation characteristics of the C-shape allow the contact piece to be interference-fitted into the through-hole of the terminal block. This causes the entire inner side of the contact piece to further adhere to the sidewall of the moving contact, reducing contact resistance and improving the current-carrying capacity under high current conditions. This ensures the circuit breaker maintains stable conductivity even during long-term operation. The fit between the deformation section and the inner wall of the through-hole, combined with the arc-shaped protrusion of the connecting portion and the end face of the lower terminal block, creates a dual-path conductivity, enhancing the safety of equipment operation.

[0026] 3. This invention, by setting a sleeve with a guide groove inside the insulating pole, and cooperating with the guide pin on the second mounting base, drives the second mounting base and the contact piece to rotate during the closing process. This can automatically scrape off the oxide layer and impurities on the outside of the deformed part, the inner wall of the through hole, and the lower end face of the terminal, ensuring that a clean and good conductive contact surface is obtained every time the circuit is closed. No additional cleaning structure or maintenance process is required, which further simplifies the internal structure and improves the reliability of long-term operation. Attached Figure Description

[0027] Figure 1 This is an overall schematic diagram of the integrated pole-mounted vacuum circuit breaker of the present invention; Figure 2 This is a top view of the integrated pole-mounted vacuum circuit breaker of the present invention; Figure 3 for Figure 2 Full sectional view at point AA; Figure 4 for Figure 3 A magnified view of a section at point B in the middle; Figure 5 This is a diagram showing the state when the first terminal and the contact piece are connected in the integrated pole-mounted vacuum circuit breaker of the present invention. Figure 6 This is a state diagram of the integrated pole-mounted vacuum circuit breaker of the present invention when it is closed; Figure 7 This is a schematic diagram of the contact piece in the present invention; Figure 8 This is a schematic diagram of the sleeve structure in this invention; Figure 9 for Figure 3 A magnified view of a section at point C.

[0028] In the diagram: 1. Insulating pole; 2. Vacuum interrupter; 3. Stationary contact; 4. Moving contact; 5. Insulating rod; 6. Current transformer; 7. Terminal block; 7a. Mounting part; 7b. Mating part; 7c. Through hole; 8. Mounting base No. 1; 9. Mounting base No. 2; 9a. Guide pin; 10. Contact piece; 10a. Connecting part; 10b. Deformation part; 10c. Sliding part; 10d. Arc-shaped protrusion; 11. Spring No. 1; 12. Limiting seat; 13. Spring No. 2; 14. Heat-conducting layer; 15. Mechanism box; 16. Y-type sealing ring; 17. Sleeve; 17a. Straight section; 17b. Inclined section; 17c. Through hole; 18. Inclined coil spring; L1. Distance between connecting part and mating part; L2. Distance between moving contact and stationary contact. Detailed Implementation

[0029] Please see Figures 1 to 9 This invention provides an integrated pole-mounted vacuum circuit breaker, the technical solution of which is as follows: An integrated pole-mounted vacuum circuit breaker, please refer to Figures 1 to 3 It includes a mechanism box 15 and three insulating poles 1. A vacuum interrupter 2 is coaxially arranged inside the insulating pole 1. A stationary contact 3 and a moving contact 4 are respectively arranged at the upper and lower ends of the vacuum interrupter 2. The upper end of the stationary contact 3 extends to the upper side of the insulating pole 1. The three insulating poles 1 are fixedly connected to the upper end of the mechanism box 15 by bolts.

[0030] Further, please refer to 3, 4, 7, and 9. An insulating rod 5, an isolation break assembly, and a current transformer 6 are coaxially arranged from bottom to top inside the insulating pole 1. The lower end of the insulating rod 5 extends into the mechanism box 15, and the insulating rod 5 is slidably connected to the mechanism box 15. A Y-shaped sealing ring 16 is provided at the sliding connection between the insulating rod 5 and the mechanism box 15, with the lip of the Y-shaped sealing ring 16 facing downwards. The mechanism box 15 is used to drive the insulating rod 5 to move vertically. The isolation break assembly includes a first mounting base 8, a second mounting base 9, a first spring 11, a contact piece 10, and a limit seat 1. 2 and spring 13, mounting base 8 are coaxially fixedly connected to the upper end of insulating rod 5, spring 11 is coaxially fixedly connected to the upper end of mounting base 8, mounting base 9 is fixedly connected to the upper end of spring 11, contact piece 10 is coaxially fixedly connected to the upper end of mounting base 9, limiting seat 12 is coaxially fixedly connected to the lower end of moving contact 4, and limiting seat 12 is located between mounting base 8 and mounting base 9, spring 13 is coaxially fixedly connected to the lower end of limiting seat 12, and the lower end of spring 13 is fixedly connected to mounting base 8. For further details, please refer to Figure 3 and 4 The current transformer 6 is fixedly installed inside the insulating pole 1, and the moving contact 4 completely penetrates to the lower side of the current transformer 6. A heat-conducting layer 14 is provided between the current transformer 6 and the inner wall of the insulating pole 1. The outer wall of the heat-conducting layer 14 is fixedly connected to the inner wall of the insulating pole 1, and the inner wall of the heat-conducting layer 14 is fixedly connected to the outer wall of the current transformer 6. For further details, please refer to Figure 3 , 47. A terminal block 7 is fixedly installed on the side wall of the insulating pole 1. The terminal block 7 includes a mounting part 7a and a mating part 7b. The mounting part 7a is located on the outside of the insulating pole 1, and the mating part 7b extends to the inside of the insulating pole 1. The mating part 7b extending into the insulating pole 1 has a through hole 7c that passes through both the upper and lower sides. The moving contact 4 is coaxially arranged with the through hole 7c. A second mounting base 9 has multiple contact pieces 10. Each contact piece 10 includes a connecting part 10a and a sliding part 10c. The connecting part 10a is fixedly connected to the second mounting base 9, and the sliding part 10c is slidably connected to the side wall of the moving contact 4. A inclined coil spring 18 is provided on the outer wall of the contact piece 10. The inclined coil spring 18 is sleeved on the outer wall of the multiple sliding parts 10c. The inclined coil spring 18 is used for... Multiple sliding portions 10c provide pressure toward the moving contact 4. A deformation portion 10b is provided between the connecting portion 10a and the sliding portion 10c. The deformation portion 10b is C-shaped with its opening facing the moving contact 4, and the maximum outer diameter of the deformation portion 10b is 22mm. The inner diameter of the through hole 7c is 20mm. The end of the connecting portion 10a near the moving contact 4 is fixedly connected to the second mounting base 9, and the end away from the moving contact 4 is in a free state. The middle part of the connecting portion 10a is provided with an upwardly protruding arc-shaped protrusion 10d. The height of the arc-shaped protrusion 10d is 3.5mm. When the insulating rod 5 is at the lower stop point, the vertical distance between the upper end of the arc-shaped protrusion 10d and the lower end face of the terminal 7 is L1=15mm, and the vertical distance between the moving contact 4 and the stationary contact 3 is L2=25mm.

[0031] For further details, please refer to Figure 4 and 8 A sleeve 17 is coaxially arranged inside the insulating pole 1. The height of the sleeve 17 is 22mm. The sleeve 17 is fixedly connected to the inner wall of the insulating pole 1. A guide groove is opened on the inner wall of the sleeve 17. The guide groove includes a straight section 17a and an inclined section 17b. The straight section 17a passes through the lower end of the sleeve 17, and the inclined section 17b passes through the upper side of the sleeve 17. A guide pin 9a is fixedly arranged on the outer wall of the second mounting base 9. When the insulating rod 5 is at the lower stop point, the guide pin 9a is located in the guide groove. The height of the straight section 17a is 10mm. Multiple through holes 17c are opened on the upper part of the sleeve 17, passing through the upper and lower sides. The multiple through holes 17c are distributed in a circumferential array. The through holes 17c are used to avoid obstructing the gas flow.

[0032] It should be further explained that the integrated pole-mounted vacuum circuit breaker provided in this embodiment is used for 10KV circuits. L1 needs to meet the insulation disconnection gap requirements in the safety specifications. If L1 is less than 12mm, it will lead to insufficient insulation margin and easy breakdown short circuit under overvoltage conditions. If L1 is greater than 18mm, it will unnecessarily increase the overall height of the insulating pole 1, which will increase the overall size of the machine. The setting of the L2 range is the basis for ensuring that the vacuum interrupter 2 can reliably extinguish the arc. If it is less than 22mm, the arc extinguishing insulation strength cannot be guaranteed. If it is greater than 28mm, it will also cause waste of pole length, increase manufacturing costs and overall weight. Furthermore, the mechanism box 15 can be a conventional mechanism box 15. That is, the mechanism box 15 is used to provide the driving force for the up and down movement of the insulating rod 5 and is used to connect with the frame. Since the mechanism box 15 technology of conventional mechanism technology is already very mature, it will not be described in detail in this embodiment.

[0033] Working principle: Please refer to Figures 1 to 9 In the initial state, that is, in the open state, the insulating rod 5 is located at the lower stop point. At this time, the second mounting base 9 and the contact piece 10 are both located below the terminal 7. The moving contact 4 and the stationary contact 3 maintain an insulation distance of L2, and the terminal 7 and the upper end of the arc-shaped protrusion 10d maintain an insulation distance of L1, forming a double disconnection structure of vacuum interrupter 2 + isolation break. The creepage distance meets the safety specifications.

[0034] When the circuit is closed, the mechanism box 15 drives the insulating rod 5 to move upward. The insulating rod 5 first drives the first mounting base 8 to move upward synchronously. The first spring 11 will first push the second mounting base 9 and the contact piece 10 to move upward, so that the contact piece 10 contacts the terminal 7 first. When the second mounting base 9 moves upward, the guide pin 9a slides upward in the straight section 17a of the guide groove of the sleeve 17. The second mounting base 9 will not rotate. As the insulating rod 5 continues to move upward, the guide pin 9a slides to the top of the straight section 17a and begins to enter the inclined section 17b. At this time, the arc-shaped protrusion 10 There is still a 5mm distance between d and the lower end face of terminal 7. At this time, the second mounting base 9, with multiple deformable parts 10b, has been inserted into the through hole 7c of terminal 7. The C-shaped deformable parts 10b are squeezed and contracted because their diameter is larger than the inner diameter of the through hole 7c. They are squeezed outward using their own elasticity and are pressed tightly against the inner wall of the through hole 7c. The sliding part 10c is pressed tightly against the side wall of the moving contact 4 under the pressure of the deformable part 10b. At this time, the inner side of the contact piece 10 is connected to the moving contact 4 through the sliding part 10c, and the outer side of the contact piece 10 is connected to the terminal 7 through the through hole 7c.

[0035] Then, the insulating rod 5 continues to move upward, and the guide pin 9a continues to slide upward along the inclined section 17b. The guide structure of the inclined section 17b will drive the second mounting base 9 to rotate as a whole. At this time, during the rotation, the outer side of the deformable part 10b and the inner wall of the through hole 7c generate relative sliding friction, which can scrape off the oxide debris, dust and impurities attached to the outer side of the deformable part 10b, and at the same time scrape off the impurities attached to the inner wall of the through hole 7c, so as to avoid the accumulation of impurities and increase the contact resistance. As the insulating rod 5 continues to move upward, the arc-shaped protrusion 10d contacts the lower end face of the terminal 7. At this time, the deformable part 10b is in contact with the inner wall of the through hole 7c, forming a double conductive path and improving the current carrying reliability. As the insulating rod 5 continues to move upward, the first mounting base 8 continues to move upward, the first spring 11 continues to be compressed, the arc-shaped protrusion 10d undergoes elastic deformation, and the second mounting base 9 continues to move upward. At this time, the guide pin 9a is still in the inclined section 17b. The second mounting base 9 continues to rotate, and the arc-shaped protrusion 10d rotates synchronously when it undergoes elastic deformation. This also removes the oxide layer and impurities attached to the lower end face of the terminal 7 and the surface of the arc-shaped protrusion 10d, ensuring that the two mating surfaces always maintain a clean conductive state. This avoids the formation of an oxide layer due to long-term moisture erosion, which would affect the conductivity. When the arc-shaped protrusion 10d reaches the elastic deformation limit, both the arc-shaped protrusion 10d and the deformed part 10b are in contact with the terminal 7. At this time, the second mounting base 9 reaches the upper stop point.

[0036] As the insulating rod 5 continues to move upward, spring 11 continues to be compressed. As mounting base 8 continues to move upward, it drives spring 13 to push limit seat 12 upward. Limit seat 12 then moves moving contact 4 upward until the top of moving contact 4 and the stationary contact 3 inside the vacuum interrupter 2 are stably engaged and connected, completing the entire closing action. Throughout the entire process from opening to closing, the time it takes for moving contact 4 to complete contact is later than the time it takes for contact piece 10 and terminal 7 to complete contact and cleaning. This ensures a reliable conductive connection is formed before the circuit is turned on, preventing the arcing phenomenon of partial contact and disconnection, further improving the safety of closing.

[0037] When the circuit breaker is tripped, the mechanism box 15 drives the insulating rod 5 to move downward. The insulating rod 5 drives the limit seat 12 to move downward. At this time, the elastic force of the first spring 11 and the second spring 13 is released until the elastic force of the second spring 13 is completely released. At this time, the elastic force of the first spring 11 is not completely released, and the contact piece 10 maintains a conductive relationship with the terminal 7. As the insulating rod 5 continues to move downward, the second spring 13 is compressed and stretched, thereby pulling the limit seat 12 downward. When the limit seat 12 moves downward, it drives the moving contact 4 to move downward, disconnecting from the stationary contact 3 first. At this time, the vacuum interrupter 2 completes the arc extinguishing first.

[0038] As the insulating rod 5 continues to move downwards, the guide pin 9a retracts from the inclined section 17b back to the straight section 17a. During this process, the second mounting base 9 rotates in the opposite direction, scraping and cleaning the two contact surfaces again to ensure clean contact surfaces for the next closing operation. Subsequently, the guide pin 9a fully enters the straight section 17a, and the insulating rod 5 continues to move downwards, causing the contact piece 10 to exit through the through hole 7c and finally return to the initial open position, forming a double-disconnected insulation structure again. The creepage distance meets the specification requirements, completing the opening operation. The entire opening process first disconnects the moving contact 4 and the stationary contact 3, and then disconnects the contact piece 10 and the terminal 7. This also avoids the problem of arcing and burning of the contact surface caused by premature disconnection of the conductive path, further improving the safety of the opening and closing operations.

[0039] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. An integrated pole-mounted vacuum circuit breaker, comprising a mechanism box (15) and three insulating poles (1), wherein a vacuum interrupter (2) is coaxially arranged inside each insulating pole (1), and a stationary contact (3) and a moving contact (4) are respectively arranged at the upper and lower ends of each vacuum interrupter (2), wherein the upper end of the stationary contact (3) extends to the upper side of the insulating pole (1), characterized in that, Three insulating poles (1) are fixedly connected to the upper end of the mechanism box (15) by bolts. An insulating rod (5), an isolation break assembly, and a current transformer (6) are coaxially arranged from bottom to top inside the insulating pole (1). The lower end of the insulating rod (5) extends into the mechanism box (15), and the insulating rod (5) is slidably connected to the mechanism box (15). The mechanism box (15) is used to drive the insulating rod (5) to move in the vertical direction. The isolation break assembly is fixedly installed at the upper end of the insulating rod (5), and the current transformer (6) is fixedly installed inside the insulating pole (1). The moving contact (4) extends completely through the lower side of the current transformer (6). The moving contact (4) is slidably connected to the isolation break assembly. A terminal (7) is fixedly installed on the side wall of the insulating pole (1). The terminal (7) extends to the inner side of the insulating pole (1). When the insulating rod (5) is at the lower stop point, the vertical distance between the isolation break assembly and the lower end face of the terminal (7) is L1, and the vertical distance between the moving contact (4) and the stationary contact (3) is L2. 12mm≤L1≤18mm, 22mm≤L2≤28mm.

2. The integrated pole-mounted vacuum circuit breaker according to claim 1, characterized in that, The isolation break assembly includes a first mounting base (8), a second mounting base (9), a first spring (11), a contact piece (10), a limiting seat (12), and a second spring (13). The first mounting base (8) is coaxially fixedly connected to the upper end of the insulating rod (5). The first spring (11) is coaxially fixedly connected to the upper end of the first mounting base (8). The second mounting base (9) is fixedly connected to the upper end of the first spring (11). The contact piece (10) is coaxially fixedly connected to the upper end of the first spring (11). The upper end of the second mounting base (9) is fixedly connected to the second mounting base (9). The limiting seat (12) is coaxially fixedly connected to the lower end of the moving contact (4). The limiting seat (12) is located between the first mounting base (8) and the second mounting base (9). The second spring (13) is coaxially fixedly connected to the lower end of the limiting seat (12). The lower end of the second spring (13) is fixedly connected to the first mounting base (8). The contact piece (10) is slidably connected to the side wall of the moving contact (4).

3. The integrated pole-mounted vacuum circuit breaker according to claim 2, characterized in that, The second mounting base (9) is provided with multiple contact pieces (10). Each contact piece (10) includes a connecting part (10a) and a sliding part (10c). The connecting part (10a) is fixedly connected to the second mounting base (9). The sliding part (10c) is slidably connected to the side wall of the moving contact (4). The outer side wall of the contact piece (10) is provided with a slanted coil spring (18). The slanted coil spring (18) is sleeved on the outer side wall of the multiple sliding parts (10c). The slanted coil spring (18) is used to provide pressure to the multiple sliding parts (10c) toward the moving contact (4).

4. An integrated pole-mounted vacuum circuit breaker according to claim 3, characterized in that, The terminal (7) extends into the insulating pole (1) and has a through hole (7c) that passes through both the upper and lower sides. The moving contact (4) is coaxially arranged with the through hole (7c). A deformation part (10b) is provided between the connecting part (10a) and the sliding part (10c). The deformation part (10b) is C-shaped with its opening facing the moving contact (4), and the maximum outer diameter of the deformation part (10b) is 0.5 to 1.5 mm larger than the inner diameter of the through hole (7c).

5. An integrated pole-mounted vacuum circuit breaker according to claim 3, characterized in that, The end of the connecting part (10a) near the moving contact (4) is fixedly connected to the second mounting base (9), and the end away from the moving contact (4) is in a free state. The middle part of the connecting part (10a) is provided with an upwardly protruding arc-shaped protrusion (10d), and the height of the arc-shaped protrusion (10d) is 2 to 5 mm.

6. An integrated pole-mounted vacuum circuit breaker according to claim 5, characterized in that, A sleeve (17) is coaxially arranged inside the insulating pole (1). The sleeve (17) is fixedly connected to the inner wall of the insulating pole (1). A guide groove is opened on the inner wall of the sleeve (17). The guide groove includes a straight section (17a) and an inclined section (17b). The straight section (17a) passes through the lower end of the sleeve (17), and the inclined section (17b) passes through the upper side of the sleeve (17). A guide pin (9a) is fixedly arranged on the outer wall of the second mounting base (9). When the insulating rod (5) is located at the lower stop point, the guide pin (9a) is located in the guide groove. The height of the straight section (17a) is less than L1.

7. An integrated pole-mounted vacuum circuit breaker according to claim 1, characterized in that, A heat-conducting layer (14) is provided between the inner wall of the current transformer (6) and the insulating pole (1). The outer wall of the heat-conducting layer (14) is fixedly connected to the inner wall of the insulating pole (1), and the inner wall of the heat-conducting layer (14) is fixedly connected to the outer wall of the current transformer (6).

8. An integrated pole-mounted vacuum circuit breaker according to claim 1, characterized in that, The sliding connection between the insulating rod (5) and the mechanism box (15) is provided with a Y-shaped sealing ring (16), and the lip of the Y-shaped sealing ring (16) faces downward.

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