Blowing arc extinguishing tank type circuit breaker and method

Abstract

The invention belongs to the field of circuit breakers, and discloses a blowing arc extinguishing tank circuit breaker and a method, the blowing arc extinguishing tank circuit breaker comprises a shell, a moving contact assembly and a static contact assembly which are connected with an operating mechanism, and an enhanced air chamber is formed by the inner wall of a moving contact and the end face, close to a static arc contact, of a moving arc contact and is communicated with a blowing cavity. And the enhanced arc blowing unit pushes the moving arc contact to move towards the static arc contact during opening so as to reduce the volume of the enhanced air chamber, so that the air pressure is increased, and air blowing and arc extinguishing are realized. In the opening process, the operating mechanism drives the cylinder body and the moving contact assembly to move, so that the air blowing cavity is rapidly shrunk, high-pressure air is generated in the air blowing cavity, and air blowing and arc extinguishing are carried out through the enhanced air chamber; when the arc is extinguished, the high-pressure gas in the gas blowing cavity flows out through the gap between the contact pull rod and the piston, so that the pressure of the gas blowing cavity is reduced, the problem of resistance caused by an over-small gas blowing port in the traditional design is avoided, the motion resistance of the moving contact can be remarkably reduced, the burden of an operating mechanism is reduced, and the switching-on and switching-off speed and the overall reliability of the circuit breaker are improved.

Description

Technical Field

[0001] The present invention belongs to the field of circuit breakers, and in particular relates to a tank-type circuit breaker and a method for extinguishing arcs by blowing air. Background Art

[0002] In power systems with voltage levels of 40.5kV and above, tank-type circuit breakers are core switchgear. They are primarily composed of a housing, arc extinguishing chamber components, insulating pull rods, and operating mechanisms. In recent years, with the rapid development of the economy and society, the scale and density of power grids have continued to grow, and short-circuit currents have also increased, placing higher demands on the stability and reliability of power systems. To address the problem of arcing between the moving and static arcing contacts when the switch is opened under high short-circuit currents, which can lead to contact damage and breaking failure, compressed air is currently commonly used for arc extinguishing. This involves compressing the gas in the cylinder and ejecting a high-speed airflow to extinguish the arc at the moment the moving and static arcing contacts separate, thereby shortening the arcing time and achieving rapid disconnection.

[0003] However, existing methods of blowing air to extinguish arcs by compressing the gas inside the circuit breaker have significant shortcomings. To achieve a high blowing speed, the diameter of the air inlet is generally designed to be small. This design can adversely affect the opening and closing speed of the moving contact after arc extinguishing and during closing. Specifically, a small air inlet increases the resistance to the moving contact's movement, which in turn increases the burden on the operating mechanism and affects the overall performance of the circuit breaker.

[0004] In summary, the compressed air arc extinguishing structure of the existing tank type circuit breaker has technical problems such as affecting the opening and closing speed of the moving contact and increasing the burden on the operating mechanism due to the small diameter of the air blowing port. Summary of the Invention

[0005] The present invention provides a tank-type circuit breaker and method for air-blowing arc extinguishing. The circuit breaker adopts an enhanced air-blowing method to extinguish arcs, which can effectively improve the arc-extinguishing capability of the circuit breaker; and after the arc extinguishing is completed, the resistance of the air-blowing chamber can be reduced, thereby increasing the opening and closing speed of the moving contact and reducing the burden on the operating mechanism.

[0006] In order to achieve the above object, the present invention adopts the following technical contents: A tank-type circuit breaker with air-blowing arc extinguishing comprises a housing; An operating mechanism is provided at one end of the housing, and the operating mechanism is connected to a moving contact assembly that can move axially along the housing; the other end of the housing is connected to a stationary contact assembly; The moving contact assembly includes a moving contact seat; a cylinder body is slidably connected in the moving contact seat; the cylinder body is connected to the operating mechanism; a piston fixed to the moving contact seat is provided in the cylinder body; an air blowing cavity is formed between the cylinder body and the piston; The cylinder body is connected to a moving contact, a moving arc contact is slidably connected inside the moving contact, and an enhanced arc blowing unit is provided between the moving arc contact and the cylinder body; The static contact assembly includes a static contact and a static arc contact provided at the other end of the housing. When the switch is closed, the static contact contacts the moving contact, and the static arc contact contacts the moving arc contact. The inner wall of the moving contact and the end surface of the moving arc contact close to the static arc contact form an enhanced air chamber connected to the blowing cavity; The enhanced arc blowing unit can push the moving arc contact towards the static arc contact during the opening process, so that the volume of the enhanced air chamber is reduced; The cylinder body is connected to the insulating rod through the contact rod; The contact rod is inserted into the piston; when the switch starts to open, the contact rod and the piston are sealed to form a closed structure in the blowing chamber, and the gas is blown from the blowing chamber through the enhanced air chamber; after the switch continues to open, a gap is formed between the contact rod and the piston for discharging the gas in the blowing chamber to reduce the air pressure in the blowing chamber.

[0007] Furthermore, the arc blowing enhancement unit includes a spring; One end of the spring is connected to the end surface of the cylinder body, and the other end is connected to the inner wall end surface of the moving arc contact; The spring can store energy when the static arc contact and the moving arc contact are in contact, and release energy when the static arc contact and the moving arc contact are separated, so as to push the moving arc contact to move.

[0008] Furthermore, The contact pull rod is inserted into the center hole of the piston and is coaxial with the center hole; the contact pull rod adopts a stepped structure, including a first rod body and a second rod body connected to each other; wherein, the first rod body is connected to the insulating pull rod, and the second rod body is connected to the cylinder body; the diameter of the first rod body is larger than the diameter of the second rod body; when the switch starts to open, the first rod body and the center hole of the piston are fitted and sealed to form a closed structure in the blowing cavity, and the gas is blown from the blowing cavity through the enhanced air chamber; after continuing to open the switch, a gap is formed between the second rod body and the center hole of the piston to reduce the gas in the blowing cavity.

[0009] Furthermore, at least one one-way valve is provided on the piston, and the flow direction of the one-way valve is arranged toward the blowing cavity.

[0010] Furthermore, one end of the housing is connected to a dynamic end flange, and the other end is connected to a static end flange; The moving contact seat is connected to the moving end flange through the moving end insulator; The static end flange is connected to a static end insulator, and the static end insulator is connected to a static contact seat; The static contact and the static arc contact are both fixedly connected to the static contact seat.

[0011] Furthermore, the dynamic contact seat is connected to a dynamic end connection seat; the static contact seat is connected to a static end connection seat.

[0012] Furthermore, the piston is connected to a piston fixing rod, and the piston fixing rod is connected to the dynamic contact seat through a piston fixing plate.

[0013] Furthermore, an air blowing port is provided on the moving arc contact; and a communication port is provided on the end surface of the cylinder body.

[0014] Furthermore, elastic contact fingers are provided in the static contact, and the outer ring of the movable contact is plug-fitted with the elastic contact fingers.

[0015] A method for operating a tank-type circuit breaker with air-blowing arc extinguishing is provided, based on the above tank-type circuit breaker with air-blowing arc extinguishing, comprising: During the closing process, the operating mechanism drives the cylinder body and the moving contact assembly to move toward the static contact assembly, so that the static arc contact contacts the moving arc contact to achieve closing. During the opening process, the operating mechanism drives the cylinder body and the moving contact assembly to move away from the static contact assembly, so that the static arc contact and the moving arc contact are separated to achieve opening. The enhanced arc blowing unit pushes the moving arc contact toward the static arc contact, so that the volume of the enhanced air chamber is reduced. Among them, when the switch starts to open, the contact rod and the piston are sealed to form a closed structure in the blowing chamber, and the gas is blown from the blowing chamber through the enhanced air chamber; after the switch continues to open, a gap is formed between the contact rod and the piston for discharging the gas in the blowing chamber to reduce the air pressure in the blowing chamber.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a tank-type circuit breaker with air-blowing arc extinguishing, comprising a housing, a moving contact assembly connected by an operating mechanism, and a static contact assembly, wherein a cylinder is connected to the moving contact, a moving arc contact is slidably connected inside the moving contact, an enhanced air chamber is formed by the inner wall of the moving contact and the end face of the moving arc contact close to the static arc contact and is connected to the air-blowing chamber, and the enhanced arc-blowing unit pushes the moving arc contact toward the static arc contact when opening the circuit breaker to reduce the volume of the enhanced air chamber, thereby increasing the air pressure and blowing out the arc. During the opening process, the operating mechanism drives the cylinder and the moving contact assembly to move, causing the air-blowing chamber to shrink rapidly, thereby generating high-pressure gas in the air-blowing chamber, and blowing out the arc through the enhanced air chamber; when the arc is extinguished, the high-pressure gas in the air-blowing chamber flows out through the gap between the contact pull rod and the piston, thereby reducing the pressure in the air-blowing chamber. This avoids the resistance problem caused by the excessively small air opening in the traditional design, can significantly reduce the movement resistance of the moving contact, reduce the burden on the operating mechanism, and improve the opening and closing speed and the overall reliability of the circuit breaker.

[0017] Preferably, in the present invention, a spring is used as the driver of the enhanced arc blowing unit. The spring automatically stores energy as the moving arc contact is compressed during the closing process. When the static arc contact and the moving arc contact are separated in the initial stage of opening, the energy stored in the spring is quickly released, forcefully pushing the moving arc contact to move to compress the enhanced air chamber and provide the required additional blowing power. This built-in energy storage and release mechanism can efficiently complete the enhanced arc blowing action without external control.

[0018] Preferably, in the present invention, a stepped contact pull rod design is adopted. In the initial stage of opening the circuit breaker, the thicker part of the pull rod is tightly fitted and sealed with the center hole of the piston, ensuring that the pressure in the blowing chamber effectively acts on the enhanced air chamber to achieve strong arc blowing and arc extinguishing; as the opening of the circuit breaker continues, the thinner part of the pull rod forms a gap through the center hole of the piston, so that the excess gas in the blowing chamber can be discharged smoothly, the air pressure is quickly reduced, and the back pressure resistance that hinders the movement of the moving contact assembly in the later stage of opening the circuit breaker is effectively eliminated, further reducing the load on the operating mechanism.

[0019] Preferably, in the present invention, a one-way valve flowing to the blowing chamber is provided on the piston, which effectively prevents the high-pressure gas in the blowing chamber from flowing back or leaking to the back side of the piston during the compression process, ensuring that a sufficiently high air pressure can be established and maintained in the blowing chamber during the blowing stage, thereby stably improving the blowing flow rate and arc extinguishing efficiency, and ensuring the reliability and consistency of the blowing arc extinguishing effect.

[0020] Preferably, in the present invention, the moving contact seat and the static contact seat are insulated and connected to the flange by the moving end insulator and the static end insulator respectively, providing a clear and reliable insulation barrier, effectively isolating the flanges at both ends of the housing of the high-voltage live parts inside the circuit breaker, preventing the current leakage path along the axial direction of the housing, and ensuring the electrical insulation performance and safe operation of the circuit breaker.

[0021] Preferably, in the present invention, connecting bases are respectively provided on the moving contact base and the stationary contact base to provide a standardized and secure electrical connection interface between the contact assembly inside the circuit breaker and the external conductive busbar or other conductor, thereby optimizing the support structure of the internal conductive components, facilitating installation and maintenance, and also contributing to the smooth conduction of current.

[0022] Preferably, in the present invention, the piston is rigidly connected to the moving contact seat through a fixed rod and a fixed plate, ensuring the absolute fixed position relationship of the piston relative to the moving contact seat, preventing the piston from shifting or shaking during the movement of the cylinder body, thereby maintaining the structural stability and sealing reliability of the blowing chamber formed between the piston and the cylinder body, which is the basis for achieving stable air pressure arc blowing.

[0023] Preferably, in the present invention, an air blowing port is opened on the moving arc contact and an annular connecting port is provided on the end face of the cylinder body, thereby optimizing the flow path of the high-pressure gas from the air blowing chamber to the enhanced air chamber and finally spraying to the arc area, forming a more efficient and concentrated high-speed air flow channel, which is conducive to applying the compressed gas energy more directly to the arc extinguishing area, improving the air blowing speed and air flow guidance, and enhancing the arc extinguishing ability.

[0024] Preferably, in the present invention, elastic contact fingers are provided in the static contact and are plugged into the outer ring of the moving contact, providing elastic pressure of multi-point and surface contact when in the closed state, significantly increasing the contact area of ​​the main conductive circuit and reducing the contact resistance, ensuring the stability and flow capacity of current conduction, effectively reducing the heating of the contact points, and improving the safety and conductivity reliability of the long-term operation of the circuit breaker.

[0025] The present invention also provides an operating method for a tank-type circuit breaker with air-blowing arc extinguishing. Based on the aforementioned tank-type circuit breaker with air-blowing arc extinguishing, during the closing process, the operating mechanism drives the cylinder and movable contact assembly toward the stationary contact assembly, bringing the stationary arc contact into contact with the movable arc contact to achieve closing. At this point, the volume of the air-blowing chamber enclosed by the cylinder and piston decreases dramatically, rapidly generating high-pressure gas to extinguish the arc. Simultaneously, the arc-blowing enhancement unit actively propels the movable arc contact toward the stationary arc contact, reducing the volume of the enhanced air chamber connecting the air-blowing chamber and increasing the airflow pressure, thereby enhancing the arc-extinguishing function. After the arc is extinguished, the high-pressure gas in the air-blowing chamber flows out through the gap between the contact pull rod and the piston, thereby reducing the pressure in the air-blowing chamber. This avoids the additional resistance caused by the overly small air opening in conventional designs, significantly reducing the resistance to the movable contact's movement, alleviating the burden on the operating mechanism, and improving the opening and closing response speed and the reliability of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic cross-sectional view of a tank-type circuit breaker with air-blowing arc extinguishing in a closed state provided by an embodiment of the present invention; Figure 2 A cross-sectional schematic diagram of the opening process of a tank-type circuit breaker with air-blowing arc extinguishing provided by an embodiment of the present invention; Figure 3 A schematic cross-sectional view of an open state of a tank-type circuit breaker with air-blowing arc extinguishing provided by an embodiment of the present invention; Figure 4 A schematic cross-sectional view of a movable contact assembly and a stationary contact assembly of a tank-type circuit breaker with air-blowing arc extinguishing provided by an embodiment of the present invention; Figure 5 A schematic cross-sectional view of a moving contact assembly provided in an embodiment of the present invention.

[0027] Reference numerals: 1. Housing; 2. Operating mechanism; 3. Insulating rod; 4. Moving contact seat; 5. Cylinder; 6. Moving contact; 7. Moving arc contact; 8. Contact rod; 9. Piston; 10. One-way valve; 11. Piston fixing rod; 12. Piston fixing plate; 13. Moving end insulator; 14. Moving end connecting seat; 15. Static contact seat; 16. Static contact; 17. Static arc contact; 18. Static end insulator; 19. Static end connecting seat; 20. Moving end flange; 21. Static end flange; 22. Spring; 23. Air blow port; 24. Connecting port. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail in the following specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0032] In the description of the embodiments of the present invention, it should be noted that if the terms "upper," "lower," "horizontal," "inner," etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the inventive product is typically placed when in use. These terms are merely for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," etc. are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0033] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0034] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0035] In order to further understand the technical solution of the present invention, the following terms are explained: Compressed-air interrupter: The space between the cylinder and piston in a compressed-air interrupter is called the blow chamber. In most designs, the cylinder and contacts are connected for joint movement, while the piston is fixed. During opening, the cylinder moves toward the piston along with the contacts, causing the blow chamber volume to decrease dramatically. At this point, the gas inside the blow chamber, under high pressure, flows along the airflow path into the nozzle, extinguishing the arc.

[0036] As mentioned in the background technology, although there are many air blowing arc extinguishing methods for current circuit breakers, most of the existing methods are to extinguish the arc by compressing the gas in the circuit breaker. In order to provide a higher blowing speed, the diameter of the blowing port is generally not large, which will result in the opening and closing speed of the moving contact being affected due to the small diameter of the blowing port after the arc extinguishing is completed and when closing the circuit breaker, thereby increasing the burden on the operating mechanism.

[0037] In order to solve the above problems, this embodiment provides a tank-type circuit breaker with air-blowing arc extinguishing, that is, an arc-extinguishing chamber with enhanced air-blowing function is proposed, which can effectively improve the arc-extinguishing ability of the circuit breaker; and after the arc extinguishing is completed, the resistance of the air-blowing chamber can be reduced, the operating work of the mechanism can be reduced, and the reliability can be improved.

[0038] like Figure 1 、 Figure 2 and Figure 3 As shown, this embodiment provides a tank-type circuit breaker with air-blowing arc extinguishing, including an operating mechanism and an arc-extinguishing chamber assembly. The arc-extinguishing chamber assembly is installed inside a housing 1. The housing 1 is a long strip structure, and a moving end flange 20 and a static end flange 21 are respectively installed on the openings at both ends. The insulating pull rod 3 passes through the moving end flange 20 to connect with the moving contact assembly.

[0039] The arc extinguishing chamber assembly includes a moving contact assembly and a static contact assembly, wherein the static contact assembly includes a static contact 16 and a static arc contact 17 installed in the center of the static contact 16. The inner ring of the static contact 16 is provided with a circle of elastic contact fingers. The static contact 16 and the static arc contact 17 are fixed on the static contact seat 15. The static contact seat 15 is fixed to the inner side of the static end flange 21 through the static end insulator 18. The side of the static contact seat 15 is also bolted to a static end connecting seat 19 for connecting to external wires.

[0040] The moving contact assembly includes a moving contact 6 and a moving arc contact 7, wherein the moving contact 6 is fixed at the front end of the cylinder body 5, and the cylinder body 5 is slidably connected to the center hole inside the moving contact seat 4. The moving contact seat 4 is fixed to the inner side of the moving end flange 20 through the moving end insulator 13, and the outer side surface of the moving contact seat 4 is also bolted to the moving end connecting seat 14 for connecting to the external wire.

[0041] like Figure 4 As shown, the moving contact 6 is a tubular structure, and the outer side of the moving arc contact 7 is slidably connected to the inside of the moving contact 6, and a spring 22 is installed inside the moving contact 6, one end of the spring 22 is connected to the cylinder body 5, and the other end is connected to the moving arc contact 7; when the moving contact assembly and the static contact assembly are closed, the end face of the moving arc contact 7 first contacts the end face of the static arc contact 17, and then the spring 22 is compressed, and the outer ring of the moving contact 6 is inserted into the elastic contact finger of the static contact 16. When opening, the arc mainly appears between the end face of the moving arc contact 7 and the end face of the static arc contact 17. Therefore, an air blowing port 23 is opened in the center of the moving arc contact 7 to realize air blowing arc extinguishing when opening. Moreover, when the circuit breaker is opened, after the moving and static arc contacts are separated, the spring 22 in a compressed state will push the moving arc contact 7 axially outward, causing the moving arc contact 7 to move relative to the moving contact 6, thereby reducing the volume of the enhanced air chamber formed by the moving arc contact 7 and the moving contact 6 and increasing the air pressure, thereby enhancing the function of air blowing and arc extinguishing; specifically, the enhanced air chamber is composed of the end face of the moving arc contact 7 close to the static arc contact 17 and the inner wall of the moving contact 6, and is used to extinguish the arc generated between the end face of the moving arc contact 7 and the end face of the static arc contact 17 during the circuit breaker opening process.

[0042] like Figure 5As shown, the cylinder body 5 is a circular cylinder with a movable contact assembly fixedly connected to its front end and an opening at the rear end. The cylinder body 5 moves back and forth within the center hole inside the movable contact seat 4 to perform opening and closing operations, maintaining a conductive connection throughout the movement. The end of the insulating pull rod 3 is threadedly connected to the contact pull rod 8, the end of which is connected to the center position of the front end of the cylinder body 5. A connecting port 24 is opened at the front end of the cylinder body 5 to connect the interior of the cylinder body 5 with the interior of the movable contact 6, facilitating the entry of gas from the interior of the cylinder body 5 into the interior of the movable contact 6, thereby achieving air blowing through the blowing port 23 of the movable arc contact 7. A piston 9 is installed within the cylinder body 5. The piston 9 is fixed by multiple piston fixing rods 11 evenly distributed around the circumference. The other end of the piston fixing rod 11 is fixed to the same piston fixing plate 12, which is fixed to the center hole inside the movable contact seat 4. This ensures the fixation of the piston 9, so that when the cylinder body 5 moves, the cylinder body 5 and the piston 9 can move relative to each other. A closed air blowing chamber is formed between the cylinder body 5 and the right side of the piston 9. When the switch is opened, the cylinder body 5 moves to the left. Since the piston 9 is fixed, the volume of the air blowing chamber becomes smaller, and the gas inside the cylinder body 5 enters the moving contact 6 from the inside of the cylinder body 5, thereby blowing air through the air blowing port 23 of the moving arc contact 7 to complete the arc extinguishing.

[0043] As another optimization scheme of this embodiment, the contact pull rod 8 passes through the center of the piston 9. In order to achieve a rapid reduction in the air pressure in the blowing chamber after the arc is extinguished and a rapid movement of the moving contact assembly, the contact pull rod 8 in this application is a stepped rod, the end connected to the insulating pull rod 3 is the large-diameter end, and the end connected to the cylinder 5 is the small-diameter end. When the switch starts to open, the large-diameter end and the center hole of the piston 9 are tightly sealed, so that the blowing chamber is a closed structure, and the gas is blown from the blowing port 23. When the switch continues to open, since the arc has been extinguished, there is no need to continue blowing. At this time, there is a large gap between the small-diameter end and the center hole of the piston 9. A large amount of gas in the blowing chamber is discharged from this gap, which reduces the air pressure in the blowing chamber, thereby reducing the load of the operating mechanism 2 and improving reliability.

[0044] As another optimization scheme of this embodiment, several one-way valves 10 are installed on the piston 9. The one-way valves can be opened to the right, that is, opened into the blowing chamber. When closing the switch, the external gas enters the blowing chamber through the one-way valves, thereby increasing the air intake speed of the blowing chamber, thereby increasing the closing speed, and also reducing the load on the operating mechanism when closing the switch.

[0045] This embodiment also provides a tank-type circuit breaker with air-blowing arc extinguishing and a method for using the method, as follows: Operating mechanism 2 drives axial movement of insulating rod 3, thereby opening and closing the moving and static contact assemblies, achieving opening and closing operations. During closing, insulating rod 3, via contact rod 8, drives cylinder 5 toward the static contact assembly, while piston 9 remains stationary. This increases the volume of the air chamber formed by cylinder 5 and piston 9, allowing gas to enter the air chamber through one-way valve 10, air port 23, and the gap between the small-diameter end of contact rod 8 and piston 9.

[0046] When closing the circuit breaker, the end face of the moving arc contact 7 first contacts the end face of the static arc contact 17, then the spring 22 is compressed, and the outer ring of the moving contact 6 is inserted into the elastic contact finger of the static contact 16 to realize the closing operation of the circuit breaker.

[0047] When opening the circuit breaker, the insulating pull rod 3 drives the cylinder body 5 to move away from the static contact assembly through the contact pull rod 8. After the moving contact 6 is pulled out from the static contact 16, the end face of the moving arc contact 7 is separated from the end face of the static arc contact 17, and an arc is generated. During this process, the large diameter end of the contact pull rod 8 is sealed against the center hole of the piston 9, making the air blowing chamber a closed structure. The gas enters the moving contact 6 from the inside of the cylinder body 5, thereby achieving air blowing and arc extinguishing through the air blowing port 23 of the moving arc contact 7. In addition, when the moving and static arc contacts are separated, the spring 22 in a compressed state will push the moving arc contact 7 outward along the axial direction, causing the moving arc contact 7 to move relative to the moving contact 6, thereby reducing the volume of the enhanced air chamber formed by the moving arc contact 7 and the moving contact 6 and increasing the air pressure, thereby enhancing the function of air blowing and arc extinguishing.

[0048] When continuing to open the circuit breaker, since the arc has been extinguished, there is no need to continue blowing. At this time, the small-diameter end of the contact rod 8 moves to the center hole position of the piston 9. There is a large gap between the small-diameter end and the center hole of the piston 9. A large amount of gas in the blowing chamber is discharged from this gap, which reduces the air pressure in the blowing chamber, thereby reducing the load of the operating mechanism 2 and improving reliability.

[0049] It can be seen that the tank type circuit breaker with air-blowing arc extinguishing provided by the present invention has the following advantages over the traditional air-blowing circuit breaker: This circuit breaker utilizes a design that enhances the arc blowing unit, which actively pushes the moving arc contact toward the stationary arc contact during opening to rapidly compress the volume of the enhanced air chamber. This creates an independent power source for high-pressure gas arc blowing, significantly increasing the arc extinguishing airflow velocity. Combined with the compressed air blowing arc extinguishing in the blowing chamber enclosed by the cylinder and piston, this enhances the arc extinguishing function of the entire arc extinguishing chamber. Furthermore, the segmented sealing and pressure relief mechanism of the stepped contact pull rod and the one-way gas flow-guiding characteristics of the piston check valve work together to ensure the effective establishment and directional injection of high-pressure airflow during the initial arc extinguishing phase, while also promptly releasing back pressure during the later stages of opening, further reducing motion resistance. Ultimately, the opening and closing actions of the entire circuit breaker system are faster and smoother, the burden on the mechanism is significantly reduced, arc extinguishing efficiency is reliably enhanced, and overall operational stability and electrical life are comprehensively improved.

[0050] The above embodiment is only one of the implementation methods that can realize the technical solution of the present invention. The scope of protection claimed by the present invention is not limited only to this embodiment, but also includes changes, replacements and other implementation methods that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention.

Claims

1. A tank type circuit breaker with air blowing arc extinguishing, characterized in that: comprising a housing (1); An operating mechanism (2) is provided at one end of the housing (1), and the operating mechanism (2) is connected to a moving contact assembly capable of axially moving along the housing (1); the other end of the housing (1) is connected to a stationary contact assembly; The movable contact assembly includes a movable contact seat (4); a cylinder body (5) is slidably connected in the movable contact seat (4); the cylinder body (5) is connected to the operating mechanism (2); a piston (9) fixed to the movable contact seat (4) is provided in the cylinder body (5); and an air blowing cavity is formed between the cylinder body (5) and the piston (9); The cylinder (5) is connected to a moving contact (6), a moving arc contact (7) is slidably connected inside the moving contact (6), and an enhanced arc blowing unit is provided between the moving arc contact (7) and the cylinder (5); The static contact assembly comprises a static contact (16) and a static arc contact (17) arranged at the other end of the housing (1); when the switch is closed, the static contact (16) contacts the moving contact (6), and the static arc contact (17) contacts the moving arc contact (7); The inner wall of the moving contact (6) and the end surface of the moving arc contact (7) close to the static arc contact (17) form an enhanced air chamber that is connected to the blowing cavity; The enhanced arc blowing unit is capable of pushing the moving arc contact (7) toward the static arc contact (17) during the opening process, so as to reduce the volume of the enhanced air chamber; The cylinder (5) is connected to the insulating pull rod (3) via the contact pull rod (8); The contact pull rod (8) is inserted into the piston (9); when the switch starts to open, the contact pull rod (8) and the piston (9) are sealed to form a closed structure in the blowing chamber, and the gas is blown from the blowing chamber through the enhanced air chamber; after the switch continues to open, a gap is formed between the contact pull rod (8) and the piston (9) for discharging the gas in the blowing chamber to reduce the air pressure in the blowing chamber.

2. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: The arc-blowing enhancement unit comprises a spring (22); One end of the spring (22) is connected to the end surface of the cylinder (5), and the other end is connected to the inner wall end surface of the moving arc contact (7); The spring (22) is capable of storing energy during the contact between the static arc contact (17) and the moving arc contact (7), and releasing energy during the separation between the static arc contact (17) and the moving arc contact (7), thereby pushing the moving arc contact (7) to move.

3. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: The contact pull rod (8) is inserted into the center hole of the piston (9) and is coaxial with the center hole; the contact pull rod (8) adopts a stepped structure, including a first rod body and a second rod body connected to each other; wherein, the first rod body is connected to the insulating pull rod (3), and the second rod body is connected to the cylinder body (5); the diameter of the first rod body is larger than the diameter of the second rod body; when the switch starts to open, the first rod body and the center hole of the piston (9) are sealed to form a closed structure in the blowing cavity, and the gas is blown from the blowing cavity through the enhanced air chamber; after the switch continues to open, a gap is formed between the second rod body and the center hole of the piston (9) to reduce the gas in the blowing cavity.

4. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: At least one one-way valve (10) is provided on the piston (9), and the flow direction of the one-way valve (10) is arranged toward the blowing cavity.

5. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: One end of the housing (1) is connected to a moving end flange (20), and the other end is connected to a static end flange (21); The moving contact seat (4) is connected to the moving end flange (20) via a moving end insulator (13); The static end flange (21) is connected to a static end insulator (18), and the static end insulator (18) is connected to a static contact seat (15); The static contact (16) and the static arc contact (17) are both fixedly connected to the static contact seat (15).

6. The tank type circuit breaker with air blowing arc extinguishing according to claim 5, characterized in that: The dynamic contact seat (4) is connected to a dynamic end connection seat (14); the static contact seat (15) is connected to a static end connection seat (19).

7. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: The piston (9) is connected to a piston fixing rod (11), and the piston fixing rod (11) is connected to the dynamic contact seat (4) via a piston fixing plate (12).

8. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: An air blowing port (23) is provided on the moving arc contact (7); and a communication port (24) is provided on the end surface of the cylinder body (5).

9. The tank type circuit breaker with air blowing arc extinguishing according to claim 1, characterized in that: An elastic contact finger is provided in the static contact (16), and the outer ring of the movable contact (6) is plug-fitted with the elastic contact finger.

10. An operating method of a tank type circuit breaker with air blowing arc extinguishing, based on the tank type circuit breaker with air blowing arc extinguishing according to any one of claims 1 to 9, characterized in that: include: During the closing process, the operating mechanism (2) drives the cylinder (5) together with the moving contact assembly to move toward the static contact assembly, so that the static arc contact (17) contacts the moving arc contact (7), thereby achieving closing; During the opening process, the operating mechanism (2) is used to drive the cylinder (5) together with the moving contact assembly to move away from the static contact assembly, so that the static arc contact (17) is separated from the moving arc contact (7), thereby achieving opening; wherein the enhanced arc blowing unit pushes the moving arc contact (7) toward the static arc contact (17), so that the volume of the enhanced air chamber is reduced; When the switch starts to open, the contact pull rod (8) and the piston (9) are sealed to form a closed structure in the blowing chamber, and the gas is blown from the blowing chamber through the enhanced air chamber; after the switch continues to open, a gap is formed between the contact pull rod (8) and the piston (9) for discharging the gas in the blowing chamber to reduce the air pressure in the blowing chamber.

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