A circuit breaker air vent opening and closing mechanism

Abstract

This invention discloses a circuit breaker heat dissipation hole opening and closing mechanism, belonging to the field of low-voltage electrical technology. It includes: a base with heat dissipation holes located near the contact points of the moving and stationary contacts; a window assembly comprising a fixed plate, a movable plate, and a spring system; the fixed plate having a heat dissipation window; and the movable plate being movable between a closed position (blocking the heat dissipation channel) and an open position (connecting the heat dissipation hole and the window); and a drive assembly including a drive plate linked to the moving contact and a transmission plate connecting the drive plate and the movable plate. When closing, the moving contact pushes the drive plate, which, via the transmission plate, drives the movable plate to overcome the spring system and move to the open position, opening the heat dissipation holes and creating convection to reduce temperature rise. When opening, the moving contact disengages from the drive plate, and the spring system drives the movable plate back to the closed position, completely sealing the heat dissipation holes, ensuring stable high-pressure airflow in the arc-extinguishing chamber, and ensuring reliable arc introduction into the metal grid. This structure effectively solves the technical contradiction of traditional circuit breakers where "sealing leads to high temperature, while opening weakens breaking capacity."

Description

Technical Field

[0001] This invention belongs to the field of low-voltage electrical appliance technology, specifically relating to a circuit breaker heat dissipation hole opening and closing mechanism. Background Technology

[0002] When a circuit breaker is closed and energized, current flows from the incoming terminal to the outgoing terminal via the contact system. Due to the inherent internal resistance of the current-carrying conductor, coupled with the unavoidable contact resistance between the moving and stationary contacts, the combined effect results in a significant current-induced thermal effect, causing the circuit breaker's temperature to rise. Temperature rise is a key performance indicator for frame circuit breakers; excessively high temperatures not only affect insulation life and mechanical stability but may also trigger unexpected tripping. Therefore, effectively controlling temperature rise while meeting safety regulations is crucial.

[0003] Traditional methods to reduce temperature rise typically include increasing the conductor cross-sectional area and using highly conductive materials (such as increasing the amount of copper busbars or silver contacts), but this directly increases the cost of raw materials. If the heat dissipation structure can be optimized without sacrificing other performance characteristics, the conductor cross-sectional area and the amount of precious metals used can be reduced while maintaining the same temperature rise level, thereby achieving cost reduction and efficiency improvement.

[0004] However, existing high-performance circuit breakers generally employ a closed-shell structure to achieve high breaking capacity. When the moving and stationary contacts break, magnetic or air blowing elongates the arc, which is then divided into multiple short arcs in series by metal grids, utilizing the "near-cathode effect" to accelerate arc extinguishing. Simultaneously, gas-generating materials (such as melamine-formaldehyde resin) are placed inside the arc-extinguishing chamber, rapidly decomposing at the high temperature of the arc to produce a large amount of gas (such as nitrogen and carbon dioxide), forming a high-pressure airflow that blows towards the arc, further enhancing the arc-extinguishing effect. To maintain the pressure inside the arc-extinguishing chamber and prevent arc leakage, the rest of the circuit breaker, except for the arc-extinguishing area, is typically designed with a highly sealed structure.

[0005] This closed design, which aims to improve breaking capacity, significantly enhances breaking performance, but severely restricts the natural convection and dissipation of internal heat, making it difficult to effectively control the temperature rise during closing operation, thus creating a technical contradiction between "high breaking capacity" and "low temperature rise".

[0006] Therefore, there is an urgent need for a structural mechanism that can both ensure the closed arc-extinguishing environment required for high breaking capacity and actively open an effective heat dissipation channel when the circuit is closed and energized, so as to take into account the two core indicators of circuit breaker breaking capacity and temperature rise control. Summary of the Invention

[0007] This invention addresses the aforementioned problems in the existing technology by proposing a circuit breaker heat dissipation hole opening and closing mechanism that can both enhance arc extinguishing effect and improve heat dissipation performance.

[0008] This invention can be achieved through the following technical solutions:

[0009] A circuit breaker heat dissipation hole opening and closing mechanism, comprising:

[0010] The base has ventilation holes that run vertically through it.

[0011] A contact system comprising a moving contact and a stationary contact, wherein the heat dissipation hole is located near the contact point between the moving contact and the stationary contact;

[0012] A window assembly includes a fixed plate, a movable plate, and an elastic system. The fixed plate is mounted on the base and has a heat dissipation window communicating with the heat dissipation holes. The movable plate is movably connected to the fixed plate, and the movable plate and the fixed plate are also connected through the elastic system.

[0013] The movable plate has a closed position and an open position. When the movable plate is in the closed position, it is blocked between the heat dissipation window and the heat dissipation hole. When the movable plate is in the open position, the heat dissipation window and the heat dissipation hole are in communication.

[0014] A drive assembly includes a drive block and a transmission block. The drive block and the moving contact form a linkage structure. The two ends of the transmission block are respectively connected to the drive block and the moving plate.

[0015] When the moving contact and the stationary contact are in a closed and energized state, the moving contact pushes the driving block, and the driving block drives the moving plate to move to the open position against the elastic system through the transmission block;

[0016] When the moving contact is disconnected from the stationary contact, the moving contact separates from the driving block, and the elastic system pushes the moving plate back to the closed position.

[0017] As a further improvement of the present invention, the fixing plate is provided with a first sliding groove, a second sliding groove and a third sliding groove. The first sliding groove extends along the width direction of the fixing plate, and the second sliding groove and the third sliding groove are symmetrically distributed on the left and right sides along the extension line of the first sliding groove, and the second sliding groove, the third sliding groove and the first sliding groove form an angle.

[0018] As a further improvement of the present invention, the distance between the second slide groove and the third slide groove near the end of the first slide groove is greater than the distance between the two ends away from the first slide groove, so that the elastic system always provides the elastic force for the moving plate to reset from the open position to the closed position.

[0019] As a further improvement of the present invention, the elastic system includes:

[0020] The first fixing pin is fixedly installed on the movable plate and located in the first sliding groove;

[0021] The second movable pin and the third movable pin are respectively installed in the second slide groove and the third slide groove;

[0022] A tension spring having three ends connected to the first fixed pin, the second movable pin, and the third movable pin, respectively.

[0023] As a further improvement of the present invention, a fourth sliding groove parallel to the first sliding groove is also provided on the fixed plate, and a first transmission block waist-shaped hole and a second transmission block waist-shaped hole are provided at both ends of the transmission block, and a fourth moving pin is connected between the fourth sliding groove and the first transmission block waist-shaped hole.

[0024] As a further improvement of the present invention, the drive block is bent and includes a horizontal part and an inclined part. A second fixing pin is installed at the end of the horizontal part away from the inclined part. The second fixing pin is connected to the waist-shaped hole of the second transmission block. The inclined part is used to withstand the downward pressure of the moving contact when the circuit is closed.

[0025] As a further improvement of the present invention, the horizontal part is also provided with a drive block waist-shaped hole, and a third fixing pin is installed in the drive block waist-shaped hole, and the third fixing pin is fixedly connected to the fixing plate.

[0026] As a further improvement of the present invention, the middle part of the transmission block is connected to the moving plate by a rotating shaft to form a lever structure.

[0027] As a further improvement of the present invention, the outer bottom surface of the base is provided with a mounting groove, the mounting groove is provided with heat dissipation fins, and the opening of the mounting groove is covered with a ventilation plate.

[0028] As a further improvement of the present invention, the ventilation plate has a plurality of ventilation holes, and the heat dissipation fins have a plurality of heat dissipation channels. The heat dissipation holes and the ventilation holes are located on both sides of the heat dissipation channels and are connected to each other.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. Balancing high breaking capacity and low temperature rise performance: When opening, the heat dissipation holes of the base are completely sealed to maintain the high-pressure airflow environment of the arc-extinguishing chamber and ensure that the arc is effectively blown into the metal grid; when closing, the heat dissipation holes of the base are completely opened, and the heat dissipation holes and the arc-extinguishing chamber form air convection, which significantly reduces the temperature rise of the contact system and successfully solves the technical contradiction of traditional circuit breakers that "the temperature rises when sealed and the breaking capacity is weak when the holes are open".

[0031] 2. Achieve instantaneous, full-stroke binary opening and closing control: The heat dissipation holes open fully immediately when the circuit is closed and close fully immediately when the arc is ignited, avoiding arc extinguishing failure or uncontrolled temperature rise caused by gradual or delayed opening and closing, ensuring that the action is strictly synchronized with the contact state, and fundamentally guaranteeing reliable arc guidance and efficient heat dissipation.

[0032] 3. Construct a high-efficiency passive heat dissipation system: By integrating heat dissipation fins, ventilation plates and through-type heat dissipation channels at the bottom of the base, the efficiency of convection and radiation heat dissipation is greatly improved without increasing volume and energy consumption, effectively suppressing long-term operating temperature rise and extending the product's electrical life.

[0033] 4. Fully mechanical linkage, high reliability and maintenance-free: No sensors, motors or external control are required. The action is completed solely by the displacement of the moving contact to drive the lever-slide-elastic system. The structure is simple, the response is fast and the anti-interference is strong. It is suitable for industrial and power distribution scenarios with high reliability requirements.

[0034] 5. Support for material cost optimization and green manufacturing: Due to the significant reduction in temperature rise, the cross-sectional area of ​​the current-carrying conductor or the amount of silver contacts can be reduced while meeting the standards, directly reducing the consumption of precious metals such as copper and silver, and achieving the green design goal of no performance degradation and cost reduction. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the circuit breaker of the present invention on the outer surface of the base;

[0036] Figure 2 This is a schematic diagram of the structure of the inner surface of the base of the present invention;

[0037] Figure 3 This is a schematic diagram of the structure of the base with heat dissipation fins and ventilation plate installed on the outer surface;

[0038] Figure 4 This is a schematic diagram showing the positions of the moving contact and the driving block when the contact system of the present invention is tripped;

[0039] Figure 5 This is a cross-sectional view of the circuit breaker when the contact system of the present invention is tripped;

[0040] Figure 6 This is a schematic diagram of the window assembly, drive block, and transmission block of the contact system of the present invention during opening.

[0041] Figure 7 This is an exploded view of the window assembly, drive block, and transmission block of the contact system of the present invention during the opening process;

[0042] Figure 8 This is a schematic diagram showing the position of the window assembly mounted on the base when the contact system of the present invention is tripped;

[0043] Figure 9 This is a schematic diagram showing the positions of the moving contact and the driving block when the contact system of the present invention is closed;

[0044] Figure 10 This is a cross-sectional view of the circuit breaker when the contact system of the present invention is closed;

[0045] Figure 11 This is a schematic diagram of the window assembly, drive block, and transmission block of the contact system of the present invention when the circuit is closed;

[0046] Figure 12 This is a schematic diagram showing the position of the window assembly mounted on the base when the contact system of the present invention is closed.

[0047] In the diagram, 100 is the base; 110 is the heat dissipation hole; 120 is the heat dissipation fin; 130 is the ventilation plate; and 131 is the ventilation hole.

[0048] 200. Moving contact; 210. Stationary contact;

[0049] 300, Fixing plate; 310, Heat dissipation window; 320, First slide rail; 321, First fixing pin; 330, Second slide rail; 331, Second moving pin; 340, Third slide rail; 341, Third moving pin; 350, Fourth slide rail; 351, Fourth moving pin;

[0050] 400. Moving plate; 410. Tension spring;

[0051] 500. Drive block; 510. Horizontal part; 511. Waist-shaped hole of drive block; 512. Second fixing pin; 513. Third fixing pin; 520. Inclined part;

[0052] 600, Transmission block; 610, First transmission block oblong hole; 620, Second transmission block oblong hole; 630, Rotating shaft. Detailed Implementation

[0053] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings to further illustrate the technical methods of the present invention. However, the present invention is not limited to these embodiments.

[0054] like Figures 1-12 As shown, the present invention provides a circuit breaker heat dissipation hole opening and closing mechanism, comprising:

[0055] The base 100 has heat dissipation holes 110 that run vertically through it;

[0056] The contact system includes a moving contact 200 and a stationary contact 210, with a heat dissipation hole 110 near the contact point between the moving contact 200 and the stationary contact 210.

[0057] The window assembly includes a fixed plate 300, a movable plate 400 and an elastic system. The fixed plate 300 is mounted on the base 100 and has a heat dissipation window 310 communicating with the heat dissipation hole 110. The movable plate 400 is movably connected to the fixed plate 300, and the movable plate 400 and the fixed plate 300 are also connected by the elastic system.

[0058] The movable plate 400 has a closed position and an open position. When the movable plate 400 is in the closed position, the movable plate 400 is blocked between the heat dissipation window 310 and the heat dissipation hole 110. When the movable plate 400 is in the open position, the heat dissipation window 310 and the heat dissipation hole 110 are connected.

[0059] The drive assembly includes a drive block 500 and a transmission block 600. The drive block 500 and the moving contact 200 form a linkage structure. The two ends of the transmission block 600 are respectively connected to the drive block 500 and the moving plate 400.

[0060] When the moving contact 200 and the stationary contact 210 are in the closed and energized state, the moving contact 200 pushes the drive block 500, and the drive block 500 drives the moving plate 400 to move to the open position through the transmission block 600 to overcome the elastic system.

[0061] When the moving contact 200 and the stationary contact 210 are disconnected, the moving contact 200 separates from the drive block 500, and the elastic system pushes the moving plate 400 to reset to the closed position.

[0062] To address the problem in existing technologies where high breaking capacity and low temperature rise are difficult to balance (the use of a closed structure to improve breaking performance leads to ineffective heat dissipation during closing operation, resulting in excessive temperature rise), this embodiment achieves intelligent opening and closing control of the heat dissipation hole 110 through the aforementioned structure:

[0063] When the circuit is closed and energized, the contact system closes and generates heat. At this time, the moving contact 200 presses down the driving block 500, which drives the moving plate 400 to overcome the elastic system and move to the open position via the transmission block 600, so that the heat dissipation hole 110 is connected to the outside air. At this time, the heat dissipation hole 110 and the air outlet of the arc-extinguishing chamber form an effective heat convection channel, which significantly enhances the heat dissipation efficiency of the contact area and effectively suppresses the temperature rise.

[0064] When the circuit breaker is tripped, the moving contact 200 disengages from the drive block 500, and the spring system automatically pushes the moving plate 400 back to the closed position, sealing the heat dissipation path and ensuring that the circuit breaker housing remains sealed. This maintains the high-pressure gas environment and arc constraint conditions required by the arc-extinguishing chamber. At this time, a large amount of gas formed by the decomposition of the gas-generating material in the arc-extinguishing chamber pushes the arc towards the metal grid of the arc-extinguishing chamber. The arc is stretched and cut by the metal grid, ensuring that the high breaking capacity is not affected.

[0065] It should be noted that the closure of the heat dissipation hole 110 during the tripping process is crucial. If the heat dissipation hole 110 is still open at the moment of tripping, the high-pressure airflow generated by the high-temperature decomposition of the gas-generating material in the arc-extinguishing chamber will flow to the heat dissipation hole 110, causing the arc to be unreliably guided to the arc-extinguishing area of ​​the metal grid. This not only reduces the arc breaking efficiency but also burns non-arc-resistant components, and in severe cases, causes internal short circuits or casing breakdown.

[0066] In response, this invention cleverly links the movement of the moving contact 200 with the opening and closing of the heat dissipation hole 110 mechanically, achieving adaptive thermal management of "heat dissipation during operation and sealing when not in operation" without the need for additional sensors or actuators. This design has at least the following advantages:

[0067] 1. Intelligent coordinated heat dissipation and sealing: When the circuit is closed and energized, the heat dissipation hole 110 is automatically opened to enhance heat dissipation in the contact area and effectively suppress temperature rise; when the circuit is opened, the heat dissipation hole 110 is immediately closed to ensure that the arc is completely guided to the arc extinguishing chamber, avoiding arc extinguishing failure and internal structural damage due to airflow leakage or path deviation, and realizing adaptive control of "working heat dissipation and disconnection sealing".

[0068] 2. Balancing high breaking capacity and low temperature rise performance: It solves the technical contradiction of traditional circuit breakers where the temperature rise is caused by the enclosed structure or the arc extinguishing effect is affected by the heat dissipation of the opening. It significantly improves thermal management without sacrificing breaking performance and meets the high standard requirements for both temperature rise and breaking capacity.

[0069] 3. Reliable structure and optimized cost: It adopts a pure mechanical linkage method, which does not require electronic components or additional drive devices, and has a timely response and is maintenance-free; at the same time, due to the reduced temperature rise, the conductor cross-sectional area or the amount of precious metals such as silver can be reduced while ensuring performance, effectively reducing material costs.

[0070] Preferably, the fixing plate 300 is provided with a first sliding groove 320, a second sliding groove 330 and a third sliding groove 340. The first sliding groove 320 extends along the width direction of the fixing plate 300. The second sliding groove 330 and the third sliding groove 340 are symmetrically distributed on the left and right sides along the extension line of the first sliding groove 320, and the second sliding groove 330, the third sliding groove 340 and the first sliding groove 320 form an angle.

[0071] The three-slide layout forms an "eight"-shaped guide structure with the first slide 320 as the axis of symmetry. This not only provides precise guidance for the translational movement of the moving plate 400, but also creates spatial conditions for the connection of the elastic system.

[0072] The distance between the second slide groove 330 and the third slide groove 340 near the end of the first slide groove 320 is greater than the distance between the ends of the two slide grooves away from the first slide groove 320, forming an "inward" slide groove layout. This inward design ensures that the tension spring 410 of the elastic system is gradually stretched when the moving plate 400 moves to the open position, and can generate a resultant force pointing to the closed position after release. No matter where the moving plate 400 is in the stroke, the direction of the elastic force is conducive to reliable reset.

[0073] Preferably, the elastic system includes:

[0074] The first fixing pin 321 is fixedly installed on the movable plate 400 and located in the first slide groove 320;

[0075] The second movable pin 331 and the third movable pin 341 are respectively installed in the second slide groove 330 and the third slide groove 340;

[0076] The tension spring 410 has three ends and is respectively connected to the first fixed pin 321, the second movable pin 331, and the third movable pin 341.

[0077] The three-end tension spring 410 structure forms a stable triangular force system. Compared with the traditional single or double spring design, the force is more balanced, which can effectively suppress the torsion or tilting of the moving plate 400 during the movement and improve the smoothness of the movement.

[0078] Overall, the coordinated design of the aforementioned multiple sliding grooves and elastic system significantly improves the reliability and durability of the opening and closing mechanism of the heat dissipation hole 110:

[0079] On the one hand, through geometric constraints and elastic force optimization, it is ensured that the moving plate 400 can quickly and completely seal the heat dissipation hole 110 when the circuit breaker is opened, thus ensuring the airtightness of the arc extinguishing chamber and the arc guiding path;

[0080] On the other hand, it avoids common faults such as loosening, jamming, or incomplete reset of the tension spring 410, so that the mechanism can maintain stable performance under long-term and frequent operation.

[0081] Preferably, the fixed plate 300 is provided with a fourth slide groove 350 parallel to the first slide groove 320, and the two ends of the transmission block 600 are provided with a first transmission block waist-shaped hole 610 and a second transmission block waist-shaped hole 620. A fourth moving pin 351 is connected between the fourth slide groove 350 and the first transmission block waist-shaped hole 610.

[0082] This structure creates a hinged connection between the transmission block 600 and the moving plate 400 that can be finely adjusted along the sliding direction. The fourth slide groove 350 restricts the moving plate 400 to only make linear movements, while the waist-shaped hole and the fourth moving pin 351 allow for angular deflection and length compensation during transmission, effectively adapting to the deformation of the mechanism under dynamic load and avoiding rigid interference.

[0083] Preferably, the drive block 500 is bent and includes a horizontal portion 510 and an inclined portion 520. A second fixing pin 512 is installed at the end of the horizontal portion 510 away from the inclined portion 520. The second fixing pin 512 is connected to the waist-shaped hole 620 of the second transmission block. The inclined portion 520 is used to withstand the downward pressure of the moving contact 200 when it is closed.

[0084] The bent structure of the drive block 500 efficiently converts the vertical downward pressure of the moving contact 200 into horizontal thrust. The inclined guide of the inclined part 520 makes the driving action smoother. At the same time, the connection between the second fixed pin 512 and the waist-shaped hole gives the drive block 500 and the transmission block 600 the necessary degree of freedom of movement, reducing stress concentration.

[0085] Preferably, the horizontal part 510 is also provided with a drive block waist-shaped hole 511, and a third fixing pin 513 is installed in the drive block waist-shaped hole 511. The third fixing pin 513 is fixedly connected to the fixing plate 300.

[0086] This design allows the drive block 500 to move axially around the third fixed pin 513. During the axial movement of the drive block 500, its oblong hole allows for slight displacement under stress, which not only ensures the stability of the drive trajectory but also mitigates the risk of jamming caused by manufacturing or assembly errors, thereby improving the reliability of the mechanism in long-term operation.

[0087] Preferably, the middle part of the transmission block 600 is connected to the moving plate 400 by a rotating shaft 630 to form a lever structure. This lever structure amplifies the displacement or force input by the drive block 500, so that a small contact stroke can drive the moving plate 400 to complete the full stroke opening and closing action, thereby improving the transmission efficiency. At the same time, the rotating shaft 630 supports and ensures the stability of the movement trajectory of the transmission block 600, reducing shaking and wear.

[0088] Overall, the combined effect of the above-mentioned structural components forms a high-precision, low-friction, and adaptive mechanical linkage system:

[0089] On the one hand, the combination design of multiple waist-shaped holes, slides and rotating shaft 630 significantly improves the mechanism's tolerance to manufacturing tolerances, thermal expansion and dynamic loads;

[0090] On the other hand, the combination of lever transmission and bending drive block 500 achieves efficient conversion of force and displacement, ensuring that heat dissipation hole 110 can be reliably opened when closing and quickly closed when opening. The overall structure does not require external energy, has fast action response and reliable reset, takes into account heat dissipation performance and arc extinguishing safety, and reduces assembly difficulty and maintenance cost.

[0091] Preferably, the base 100 has an installation groove on its outer bottom surface, a heat dissipation fin 120 is provided in the installation groove, and a ventilation plate 130 is covered at the opening of the installation groove. The ventilation plate 130 has a plurality of ventilation holes 131, the heat dissipation fin 120 has a plurality of heat dissipation channels, and the heat dissipation holes 110 and the ventilation holes 131 are located on both sides of the heat dissipation channels and are connected.

[0092] The structure creates a through-type high-efficiency heat conduction air duct at the bottom of the base 100. When the heat dissipation hole 110 is opened, the internal hot air enters the heat dissipation channel between the heat dissipation fins 120 through the heat dissipation hole 110, and is then discharged to the external environment through the ventilation hole 131 on the ventilation plate 130. The arrangement of the heat dissipation fins 120 greatly increases the heat dissipation surface area and enhances the convection and radiation heat dissipation effect.

[0093] By integrating the heat dissipation holes 110, heat dissipation fins 120 and ventilation plate 130, the present invention significantly improves the passive heat dissipation capability in the closed state without increasing the overall volume of the circuit breaker, and effectively reduces the temperature rise of the contact system.

[0094] Meanwhile, since the ventilation path is only open when the circuit is closed and cut off by the moving plate 400 when the circuit is open, it not only avoids the impact of gas leakage on the arc extinguishing performance during the disconnection process, but also realizes intelligent thermal management of "heat dissipation on demand", further enhancing the safety and energy efficiency of the product.

[0095] Specifically, the detailed operating procedures of the contact system during closing and opening are summarized and explained as follows:

[0096] I. Closing Process

[0097] Moving contact 200 moves downward to close: The operating mechanism drives the moving contact 200 to move downward and make contact with the stationary contact 210, thus completing the circuit closure. At this time, current flows through the contact system and the contact area begins to heat up.

[0098] The moving contact 200 pushes the inclined portion 520 of the drive block 500: When the moving contact 200 closes, it applies downward pressure to the inclined portion 520 of the drive block 500. Due to the guiding effect of the inclined surface, the vertical force is converted into a horizontal pushing force, which pushes the drive block 500 to move along the axial direction of its horizontal portion 510.

[0099] The horizontal part 510 of the drive block 500 pulls the transmission block 600: When the horizontal part 510 of the drive block 500 moves axially, it pushes the second transmission block waist-shaped hole 620 of the transmission block 600 through the second fixing pin 512 at its end, so that the transmission block 600 rotates around the central pivot 630.

[0100] The transmission block 600 pushes the moving plate 400 to slide: During the rotation of the transmission block 600, the fourth transmission pin located in the waist-shaped hole 610 of its first transmission block moves along the fourth slide groove 350 of the moving plate 400. During this process, the moving plate 400 overcomes the tension of the elastic system and moves from the closed position to the open position.

[0101] Heat dissipation channel connection: After the movable plate 400 is moved to the open position, the heat dissipation hole 110 on the base 100 is connected to the heat dissipation window 310 on the fixed plate 300. The internal hot air enters the bottom mounting groove through this channel, flows through the heat dissipation channel of the heat dissipation fins 120, and is discharged from the ventilation hole 131 of the ventilation plate 130, so as to achieve efficient heat dissipation.

[0102] II. Circuit Breaking Process

[0103] Moving contact 200 moves upward and separates: The tripping mechanism is activated, the operating mechanism is released or reversed, causing the moving contact 200 to retract upward and separate from the stationary contact 210, and the circuit is broken; at this time, an electric arc is generated between the contacts and is quickly guided to the arc extinguishing chamber.

[0104] The inclined portion 520 of the drive block 500 loses its downward pressure: As the moving contact 200 rises, its downward pressure on the inclined portion 520 of the drive block 500 disappears, and the drive block 500 is no longer subjected to the pushing force in the closing direction and is in a free state.

[0105] The elastic system releases the reset force: During the closing process, the elastic system (composed of a three-end tension spring 410 and the first, second, and third moving / fixed pins) begins to release stored energy, generating a resultant force pointing in the closing direction, which acts on the moving plate 400.

[0106] The movable plate 400 automatically slides to the closed position: Under the action of elastic force, the movable plate 400 slides along the guide tracks of the first slide groove 320, the second slide groove 330 and the third slide groove 340; at the same time, the fourth movable pin 351 in the fourth slide groove 350 (connecting the first transmission block waist-shaped hole 610 of the transmission block 600) moves accordingly, guiding the movable plate 400 to return to its original position smoothly until the passage between the heat dissipation window 310 and the heat dissipation hole 110 is completely blocked.

[0107] The transmission block 600 drives the drive block 500 to reset: the moving plate 400 moves to the left and pulls one end of the transmission block 600 through the fourth moving pin 351, causing the transmission block 600 to rotate in the opposite direction around the central rotating shaft 630; the other end of the transmission block 600 drives the second fixed pin 512 through the second transmission block waist-shaped hole 620, thereby pushing the drive block 500 to move back and reset, preparing for the next closing action.

[0108] The heat dissipation channel is completely sealed: After the moving plate 400 returns to the closed position, the heat dissipation path is completely sealed, ensuring that a sealed space is formed inside the circuit breaker housing (especially the arc extinguishing area); at this time, the high-pressure gas generated by the high-temperature decomposition of the gas-generating material in the arc extinguishing chamber cannot escape from the bottom heat dissipation hole 110, the airflow direction is stable, and the arc is reliably blown into the metal grid, achieving efficient and safe disconnection.

[0109] The opening and closing processes form a complete closed loop. All actions are automatically completed by mechanical linkage, with rapid response and reliable sealing. This ensures high breaking performance and avoids arc path disorder or internal structural damage caused by the opening of heat dissipation hole 110.

[0110] Because the movement of the movable plate 400 and the opening / closing of the movable contact 200 form a direct mechanical linkage structure through the drive block 500 and the transmission block 600, the opening and closing action of the entire heat dissipation hole 110 completely follows the motion state of the contact system and responds synchronously.

[0111] The moving contact 200 of the circuit breaker, driven by the operating mechanism, completes its closing and opening actions instantly within milliseconds. Once the moving contact 200 disengages from the inclined part 520 of the drive block 500 (when opening) or re-presses the drive block 500 (when closing), the external force state of the drive block 500 changes immediately and is then instantly transmitted to the moving plate 400 through the transmission block 600.

[0112] Therefore, the opening and closing of the heat dissipation hole 110 is not a delayed response or dependent on external control, but occurs strictly synchronously and instantly with the contact action. This instantaneous linkage mechanism of "contact movement - hole opening / closing immediately" ensures that heat dissipation is initiated as soon as heat is generated after closing; and sealing is completed the instant the arc is ignited during opening, preventing arc gas from leaking from the heat dissipation hole 110, thereby achieving efficient and precise thermal management while ensuring high breaking reliability.

[0113] It should be noted here that if the opening and closing of the heat dissipation hole 110 is not instantaneous, but rather gradually opens or closes along the travel of the moving contact 200, it will lead to a series of serious technical problems, mainly manifested in arc extinguishing reliability and temperature rise control failure.

[0114] 1. During the tripping process, the heat dissipation hole 110 was not fully closed in time → pressure leakage in the arc extinguishing chamber, arc out of control:

[0115] In the initial stage of circuit breaker tripping (within the first few milliseconds after the contacts separate), the arc energy is at its maximum. The arc-extinguishing chamber relies on the rapidly established high-pressure gas environment to blow the arc into the grid. If the heat dissipation hole 110 is still partially open at this stage (because the follower contact 200 slowly closes), the high-pressure gas will escape from the heat dissipation hole 110, resulting in the inability to form an effective pressure gradient in the arc-extinguishing chamber. The gas blowing force is insufficient, and the arc is "sucked" towards the heat dissipation hole 110, deviating from the path of the metal grid. This may cause the arc to remain, reignite, or even spray outwards, seriously threatening the safety of the insulation system and surrounding equipment.

[0116] 2. During the closing process, the heat dissipation vent 110 was not fully opened in time → Initial heat could not be dissipated in time, resulting in localized overheating:

[0117] The current flows immediately upon closing, and the contact resistance can generate significant heat within the first tens of milliseconds. If the heat dissipation hole 110 only opens slowly with the moving contact 200 and remains in a small or half-open state before fully closing, it will result in insufficient heat dissipation channel cross-sectional area and extremely low convection efficiency. Heat accumulates in the contact area, and the temperature rise rate is much higher than the steady-state value, increasing the contact resistance and forming a vicious cycle.

[0118] Therefore, the opening and closing of the heat dissipation hole 110 of the circuit breaker must be a binary action of "fully open" or "fully closed", and strictly synchronized with the instantaneous action state of the moving contact 200 (rather than the motion process). The structure provided in this embodiment can not only realize the opening and closing of the heat dissipation hole 110 based on the action of the moving contact 200, but also ensure that the opening and closing of the heat dissipation hole 110 is completed instantaneously, thereby avoiding the above-mentioned risks and realizing safe, efficient and reliable coordinated control.

[0119] The technical means disclosed in this invention are not limited to those described above, but also include technical solutions composed of any combination of the above technical features. The above are specific embodiments of this invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this invention, and these improvements and modifications are also considered within the scope of protection of this invention.

[0120] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0121] Furthermore, in this invention, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly specified. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0122] The technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0123] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A circuit breaker heat dissipation hole opening and closing mechanism, characterized in that, include: The base has ventilation holes that run vertically through it. A contact system comprising a moving contact and a stationary contact, wherein the heat dissipation hole is located near the contact point between the moving contact and the stationary contact; A window assembly includes a fixed plate, a movable plate, and an elastic system. The fixed plate is mounted on the base and has a heat dissipation window communicating with the heat dissipation holes. The movable plate is movably connected to the fixed plate, and the movable plate and the fixed plate are also connected through the elastic system. The movable plate has a closed position and an open position. When the movable plate is in the closed position, it is blocked between the heat dissipation window and the heat dissipation hole. When the movable plate is in the open position, the heat dissipation window and the heat dissipation hole are in communication. A drive assembly includes a drive block and a transmission block. The drive block and the moving contact form a linkage structure. The two ends of the transmission block are respectively connected to the drive block and the moving plate. When the moving contact and the stationary contact are in a closed and energized state, the moving contact pushes the driving block, and the driving block drives the moving plate to move to the open position against the elastic system through the transmission block; When the moving contact is disconnected from the stationary contact, the moving contact separates from the driving block, and the elastic system pushes the moving plate back to the closed position; The fixing plate is provided with a first sliding groove, a second sliding groove and a third sliding groove. The first sliding groove extends along the width direction of the fixing plate. The second sliding groove and the third sliding groove are symmetrically distributed on the left and right sides along the extension line of the first sliding groove, and the second sliding groove, the third sliding groove and the first sliding groove form an angle. The fixed plate is also provided with a fourth slide groove parallel to the first slide groove. The two ends of the transmission block are provided with a first transmission block waist-shaped hole and a second transmission block waist-shaped hole. A fourth moving pin is connected between the fourth slide groove and the first transmission block waist-shaped hole. The drive block is bent and includes a horizontal part and an inclined part. A second fixing pin is installed at the end of the horizontal part away from the inclined part. The second fixing pin is connected to the waist-shaped hole of the second transmission block. The inclined part is used to withstand the downward pressure of the moving contact when the circuit is closed.

2. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 1, characterized in that, The distance between the second slide and the third slide near the end of the first slide is greater than the distance between the two away from the end of the first slide, so that the elastic system always provides the elastic force to reset the moving plate from the open position to the closed position.

3. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 1, characterized in that, The elastic system includes: The first fixing pin is fixedly installed on the movable plate and located in the first sliding groove; The second movable pin and the third movable pin are respectively installed in the second slide groove and the third slide groove; A tension spring having three ends connected to the first fixed pin, the second movable pin, and the third movable pin, respectively.

4. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 1, characterized in that, The horizontal part is also provided with a drive block waist-shaped hole, and a third fixing pin is installed in the drive block waist-shaped hole. The third fixing pin is fixedly connected to the fixing plate.

5. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 1, characterized in that, The middle part of the transmission block is connected to the moving plate by a rotating shaft to form a lever structure.

6. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 1, characterized in that, The base has an installation groove on its outer bottom surface, and heat dissipation fins are installed in the installation groove. The opening of the installation groove is covered with a ventilation plate.

7. The circuit breaker heat dissipation hole opening and closing mechanism according to claim 6, characterized in that, The ventilation plate has several ventilation holes, and the heat dissipation fins have several heat dissipation channels. The heat dissipation holes and the ventilation holes are located on both sides of the heat dissipation channels and are connected.

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