Arc extinguishing device and circuit breaker

Abstract

The invention belongs to the field of circuit breakers, and discloses an arc extinguishing device and a circuit breaker, the arc extinguishing device comprises two air compression chambers which are connected in parallel, the two air compression chambers share the same piston rod, the two air compression chambers are both communicated with a fracture, the piston rod can synchronously compress the two air compression chambers to form required pressure difference or outlet flow velocity difference, and then eddy current is formed. According to the utility model, hot air entering the expansion chamber is cooled, and then high-pressure cold-state insulating gas is blown to the fracture, or the high-pressure cold-state insulating gas forming eddy current is directly blown to the fracture, so that the breaking capacity is improved; by adopting the device, the on-off performance of the arc extinguish chamber is improved, and compared with a traditional method, the on-off performance can be improved without adopting a mode of increasing operation work, and the operation reliability and efficiency of the circuit breaker are improved; the arc extinguishing device is simple in structure and principle, convenient to implement, operate and maintain, good in breaking performance and good in popularization and application value.

Description

Technical Field

[0001] The invention belongs to the field of circuit breakers, and in particular relates to an arc extinguishing device and a circuit breaker. Background Art

[0002] In the power system, in addition to carrying the rated current, the circuit breaker also needs to open and close the fault current caused by phase-to-phase short circuit or grounding. In general, the fault current is much greater than the rated current. Existing circuit breakers are mainly based on the principle of compressed air or self-energy arc extinguishing chamber. In the scheme of compressed air arc extinguishing principle, mechanical energy is mainly used to compress the gas in the cylinder to generate high-pressure airflow, which is sprayed between the broken arc contacts to extinguish the arc generated between the moving and static arc contacts, thereby breaking the fault current. In the scheme of self-energy arc extinguishing principle, a double air chamber structure of a compressed air chamber and an expansion chamber is set in the arc extinguishing chamber. The gas in the compressed air chamber enters the expansion chamber through mechanical compression to increase the pressure of the expansion chamber. At the same time, the arc energy during the breaking process is used to further increase the pressure of the expansion chamber. The adoption of this scheme can greatly reduce the mechanical energy required for circuit breaker operation. The self-energized arc extinguishing principle scheme, when interrupting a small short-circuit current, the arc energy is small, and the pressurization effect on the expansion chamber is limited. It mainly relies on mechanical compression of the compressed air chamber to allow the internal gas to enter the expansion chamber, thereby building up the pressure required to extinguish the arc in the expansion chamber, and finally extinguishing the arc to interrupt the fault current; when interrupting a large short-circuit current, the arc energy is large, and the pressure building of the expansion chamber mainly depends on the arc energy. The compressed air chamber mainly plays an auxiliary role. The expansion chamber can build up enough pressure by relying on the large current arc energy. When the fault current passes through zero, the high-pressure gas in the expansion chamber blows toward the fracture to extinguish the arc, thereby interrupting the fault current.

[0003] The existing large-capacity self-energized arc extinguishing chamber circuit breaker is provided with a compressed air chamber and an expansion chamber. The volumes of the expansion chamber and the compressed air chamber are mainly determined by the breaking current. In general, the volume of the expansion chamber gives priority to the boosting effect provided by the arc energy, and the compressed air chamber assists in providing the pressure required by the expansion chamber, which can fully guarantee the large current breaking capacity; when the small current is broken, due to the small arc energy, it is impossible to provide sufficient boosting effect for the expansion chamber, and the insufficient pressure of the expansion chamber may cause the small current breaking failure. Based on the existing technical scheme, there are two feasible solutions. The first is to reduce the expansion chamber to increase the pressure of the expansion chamber, but it may affect the large current breaking capacity; the second is to increase the volume of the compressed air chamber, and through mechanical compression, more insulating gas enters the expansion chamber from the compressed air chamber to increase the pressure of the expansion chamber. This method will increase the operating work required by the circuit breaker and cause additional mechanical operation burden. The existing large-capacity compressed air arc extinguishing chamber circuit breaker is provided with a compressed air chamber. In general, when the small current is broken, due to the small arc energy, as long as the compressed air chamber can provide sufficient pressure, its small current breaking performance can be guaranteed. However, when breaking high currents, due to the large arc energy, the compressed air chamber needs to build up a sufficiently high pressure to ensure the pressure-building effect of the fracture, so as to ensure the high current breaking performance; this method will increase the operating power required for the circuit breaker and cause additional mechanical operating burden.

[0004] It can be seen that the existing arc extinguishing chamber structure mainly improves the breaking performance by increasing the operating work, which will reduce the operating reliability of the mechanism and the body. Summary of the invention

[0005] The present invention provides an arc extinguishing device and a circuit breaker to solve the technical problem that the existing arc extinguishing chamber adopts a method of increasing operating power to improve the breaking performance, which easily causes the mechanical operation reliability of the mechanism and the body to be reduced.

[0006] In order to achieve the above object, the present invention adopts the following technical contents: An arc extinguishing device comprises two parallel-connected compressed air chambers; The air compression chamber pistons of the two air compression chambers are connected to the same piston rod; The piston passages of the two air compression chambers are both connected to the fracture; Among them, under the action of the piston rod, the two compression chambers are driven to be compressed synchronously to form a pressure difference or an outlet flow rate difference, so that the two compression chambers can press high-pressure cold insulating gas into the fracture.

[0007] Further, the two compressed air chambers include a first compressed air chamber and a second compressed air chamber, which are formed by separating the compressed air cylinder with a compressed air cylinder partition; The first compressed air chamber is arranged around the piston rod, and the second compressed air chamber is arranged around the first compressed air chamber.

[0008] Further, the first air compression chamber and the second air compression chamber are set with different lengths; or, the first piston channel corresponding to the first air compression chamber and the second piston channel corresponding to the second air compression chamber are provided with through holes with different cross-sectional areas.

[0009] Furthermore, the first compressed air chamber and the second compressed air chamber are set to different lengths; and the first piston channel corresponding to the first compressed air chamber and the second piston channel corresponding to the second compressed air chamber are provided with through holes with different cross-sectional areas.

[0010] Furthermore, the piston passages of the two air compression chambers are connected to the fracture through the expansion chamber; The first compressed air chamber is formed by the outer wall of the piston rod, the compressed air chamber piston located at one end of the first compressed air chamber, and the first pressure relief valve seat located at the other end of the first compressed air chamber; The second compressed air chamber is formed by the inner wall of the compressed air cylinder, a compressed air chamber piston located at one end of the second compressed air chamber, and a second pressure relief valve seat located at the other end of the second compressed air chamber.

[0011] Furthermore, one or more one-way valve plates are arranged on the air compression chamber piston; the air compression chamber piston is connected to the air compression cylinder partition in an integrated or detachable manner.

[0012] Furthermore, the one-way valve plate adopts a screw guide structure or an axle pin guide structure, and both the screw guide structure and the axle pin guide structure include a valve plate, so that the insulating gas is pressed out from both sides of the valve plate at the same time.

[0013] Furthermore, a guide cylinder is arranged between the first pressure relief valve seat and the second pressure relief valve seat, and the guide cylinder is used to provide movement space for the pressure cylinder partition; a guide sleeve is arranged on the inner wall of the guide cylinder for providing guidance for the pressure cylinder partition; and an exhaust hole is opened on the side wall or end of the guide cylinder.

[0014] Furthermore, the return air passages of the two compressed air chambers are double return air passages.

[0015] A circuit breaker comprises the above arc extinguishing device.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides an arc extinguishing device, which includes two parallel compressed air chambers, the two compressed air chambers share the same piston rod, and the two compressed air chambers are connected to the fracture, the piston rod can synchronously compress the two compressed air chambers to form a required pressure difference or outlet flow rate difference, thereby forming a vortex, cooling the hot air entering the expansion chamber, and then blowing the high-pressure cold insulating gas to the fracture, or directly blowing the high-pressure cold insulating gas that forms the vortex to the fracture, thereby improving the breaking capacity; the use of this device not only improves the breaking performance of the arc extinguishing chamber, but also, compared with the traditional method, does not need to increase the operating power to improve the breaking performance, thereby improving the operating reliability and efficiency of the circuit breaker; the arc extinguishing device has a simple structure and principle, is easy to implement and maintain, has good breaking performance, and has good promotion and application value.

[0017] Preferably, in the present invention, two compressed air chambers, namely the first compressed air chamber and the second compressed air chamber, are separated by a compressed air cylinder partition and are respectively arranged around the outer wall of the piston rod and the inner wall of the compressed air cylinder, thereby optimizing the structural layout of the compressed air chambers, improving space utilization, and ensuring independence and synchronization between the compressed air chambers.

[0018] Further preferably, in the present invention, by setting the first pressure chamber and the second pressure chamber with different lengths, the volume of the pressure chamber can be adjusted according to actual needs, so as to flexibly control the pressure generated during the compression process, ensure the formation of pressure difference, and further optimize the arc extinguishing performance.

[0019] Further preferably, in the present invention, by providing through holes with different cross-sectional areas for the first pressure chamber and the second pressure chamber, the flow rate of the gas during the compression process can be further adjusted, thereby ensuring the formation of an outlet flow rate difference, making the arc extinguishing process more stable and efficient.

[0020] Further preferably, in the present invention, by combining the design of compressed air chambers of different lengths and through holes of different cross-sectional areas, the volume of the compressed air chamber and the flow rate of the gas can be adjusted simultaneously, thereby achieving more precise arc extinguishing control and improving the adaptability and flexibility of the arc extinguishing device.

[0021] Further preferably, in the present invention, a one-way valve plate is provided on the air compression chamber piston. After the one-way valve plate is closed, it can ensure that the gas can only flow in one direction, thereby preventing the backflow and leakage of the gas and improving the arc extinguishing efficiency. At the same time, the air compression chamber piston and the air compression cylinder partition are connected in an integrated or detachable manner, which is convenient for installation and maintenance.

[0022] Further preferably, in the present invention, a one-way valve plate with a screw guide structure is used to ensure that the insulating gas is pressed out from both sides of the valve plate at the same time, thereby increasing the air flow channel between the compression chamber and the expansion chamber, improving the air flow transmission efficiency from the compression chamber to the expansion chamber during small current interruption, improving the small current breaking capacity, and further enhancing the arc extinguishing effect.

[0023] Further preferably, in the present invention, by providing a guide cylinder and a guide sleeve, a stable movement space is provided for the air compression cylinder partition, thereby ensuring the synchronous compression of the air compression chamber and the smooth flow of gas.

[0024] Further preferably, in the present invention, a double return air channel design is adopted, which can accelerate the gas reflux efficiency and improve the gas utilization rate, while also facilitating the cooling of the fracture and enhancing its breaking performance.

[0025] The present invention also provides a circuit breaker, including the above-mentioned arc extinguishing device. The circuit breaker adopts an arc extinguishing device with good breaking performance, which can significantly improve the arc extinguishing performance and reliability of the circuit breaker, reduce operating work and mechanical burden, and also help to improve the stability and safety of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of an arc extinguishing device provided in an embodiment of the present invention; Figure 2 A first structural schematic diagram of a dual pressure air chamber provided in an embodiment of the present invention; Figure 3 A second structural schematic diagram of a dual pressure air chamber provided in an embodiment of the present invention; Figure 4 A third structural schematic diagram of a dual pressure air chamber provided in an embodiment of the present invention; Figure 5 A schematic diagram of a first structure of a compression chamber piston assembly provided in an embodiment of the present invention; Figure 6 A schematic diagram of a second structure of a piston assembly for a compression chamber provided in an embodiment of the present invention; Figure 7 A schematic diagram of the structure of a pressure relief valve provided in an embodiment of the present invention; Figure 8 A schematic diagram of the structure of the return air channel on the pressure relief valve seat provided in an embodiment of the present invention; Fig. 9 A schematic diagram of realizing the pressure difference provided by an embodiment of the present invention; Fig.10 A schematic diagram of realizing the flow rate difference provided by an embodiment of the present invention; Fig.11 A schematic diagram of a small current interruption of a self-energy arc extinguishing chamber provided in an embodiment of the present invention; Fig.12 A schematic diagram of a high current interruption of a self-energy arc extinguishing chamber provided in an embodiment of the present invention; Fig.13 A schematic diagram of the double-pressure cylinder structure of a compressed air arc extinguishing chamber provided in an embodiment of the present invention; Fig.14Schematic diagram of the one-way valve structure provided in an embodiment of the present invention; wherein (a) is a conventional design; (b) is the one-way valve of the present application; Fig.15 Schematic diagram of the pressure relief valve seat structure provided in an embodiment of the present invention; wherein (a) is a conventional design; (b) is the pressure relief valve of the present application; Fig.16 Schematic diagram of the three-dimensional structure of the pressure relief valve seat provided in an embodiment of the present invention; wherein (a) is a conventional design; and (b) is the pressure relief valve of the present application.

[0027] Reference numerals: 1. Moving side support seat; 2. Piston rod; 3. Guide cylinder; 4. First return air valve plate; 5. Second return air valve plate; 6. Second pressure relief valve seat; 7. First pressure relief valve seat; 8. Compressed air cylinder partition; 9. Compressed air cylinder; 10. Compressed air chamber piston; 11. Second one-way valve plate; 12. First one-way valve plate; 13. Inner nozzle; 14. Moving main contact; 15. Main nozzle; 16. Static side arc contact; 17. Static side main contact; 18. First compressed air chamber; 19. Second compressed air chamber; 20. Second piston channel; 21. First piston channel; 22. Expansion chamber; 23. Moving side arc contact; 24. One-way valve plate; 25. Second guide rod; 26. First guide rod; 27. Guide rod; 28. Guide sleeve; 29. ​​Exhaust hole; 30. First protrusion; 31. Second protrusion. 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 used to limit the present invention.

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 here 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 claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are 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, further definition and explanation thereof is not required 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. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood 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", which 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 is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] Example As mentioned in the background technology, at present, the circuit breaker of the self-energizing arc extinguishing chamber solution can effectively use the arc energy to increase the pressure of the insulating gas in the expansion chamber. The advantage of this feature is more obvious when breaking a larger short-circuit current (≥60% rated short-circuit breaking current). However, when breaking a smaller short-circuit current, due to the small arc energy, the pressurization of the expansion chamber mainly depends on the gas flowing into the compressed air chamber, which may cause insufficient pressure in the expansion chamber and affect the breaking capacity of the arc extinguishing chamber. In order to solve this problem, the conventional method is to increase the opening speed and increase the pressure difference between the working air chamber and the arc area, so that the airflow can flow into the arc area quickly, increase the gas density and flow rate in the arc area, and achieve the purpose of arc extinguishing. This method will increase the operating work and reduce the reliability of the mechanism and the main body operation. In order to solve the above problems, the present embodiment provides an arc extinguishing device, which adopts a dual-pressure cylinder structure design, including components such as a valve plate, a pressure relief valve seat, an air flow channel and an air flow guide structure, to achieve a pressure difference between the two pressure cylinders, and then the air flows of different pressures or different flow rates blown from the pressure cylinders to the expansion chamber (self-energy circuit breaker) or the fracture area (compressed air circuit breaker) converge to generate vortices, thereby improving the cooling effect of the air flow on the arc extinguishing area and improving the breaking performance of the arc extinguishing chamber.

[0036] In order to facilitate understanding of the technical solution provided by the present invention, the following technical terms are explained: Self-energy arc extinguishing chamber: It mainly relies on the energy of the arc itself to heat the gas in the expansion chamber to increase its pressure. When the current passes through zero, the high-pressure gas blows toward the arc to extinguish the arc. Compressed air chamber: an air cavity that builds pressure through mechanical compression; Expansion chamber: A gas chamber that builds pressure by heating the gas in the chamber through the energy of the arc itself.

[0037] like Figure 1 As shown, this embodiment provides an arc extinguishing device, including two parallel compressed air chambers, namely a first compressed air chamber 18 and a second compressed air chamber 19, and the two compressed air chamber pistons 10 are fixedly connected to the same piston rod 2. Under the action of external mechanical force, the insulating gas in the first compressed air chamber 18 and the second compressed air chamber 19 can be pressed into the fracture; wherein, in the self-energizing circuit breaker, the insulating gas first enters the expansion chamber 22 through the compressed air chamber, and then blows toward the fracture; in the compressed air circuit breaker, the insulating gas is directly blown toward the fracture through the compressed air chamber.

[0038] In this embodiment, the arc extinguishing device is described by taking a self-energized circuit breaker as an example. Of course, compressed air circuit breakers including the arc extinguishing device provided in this embodiment are all within the protection scope of this application.

[0039] The first compressed air chamber 18 is connected to the expansion chamber 22 through the first piston passage 21, and the first piston passage 21 is provided with a first one-way valve plate 12. The second compressed air chamber 19 is connected to the expansion chamber 22 through the second piston passage 20, and the second piston passage 20 is provided with a second one-way valve plate 11; the expansion chamber 22 is connected to the fracture.

[0040] The first pressure chamber 18 is disposed around the piston rod 2 , and the second pressure chamber 19 is disposed around the first pressure chamber 18 .

[0041] Figure 2 , Figure 3 and Figure 4As shown, all of them are compressed air chamber structures. Among them, the first compressed air chamber 18 is formed by the outer wall of the piston rod 2, the compressed air chamber piston 10, the compressed air cylinder partition 8 and the first pressure relief valve seat 7. The change in the length of the first compressed air chamber 18 can be achieved by changing the thickness of the compressed air chamber piston 10 located in the first compressed air chamber 18 and the thickness of the first pressure relief valve seat 7. The second compressed air chamber 19 is formed by the compressed air cylinder partition 8, the compressed air chamber piston 10, the inner wall of the compressed air cylinder 9 and the second pressure relief valve seat 6. The change in the length of the second compressed air chamber 19 can be achieved by changing the thickness of the compressed air chamber piston 10 located in the second compressed air chamber 19 and the thickness of the second pressure relief valve seat 6.

[0042] like Figure 2 As shown, the first pressure relief valve seat 7 is convexly arranged so that the length of the first pressure chamber 18 is smaller than that of the second pressure chamber 19; Figure 3 As shown, one end of the compression chamber piston 10 of the first compression chamber 18 is protruding, so that the length of the first compression chamber 18 is smaller than that of the second compression chamber 19; Figure 4 As shown, both ends of the first pressure relief valve seat 7 and the pressure chamber piston 10 are convexly arranged, so that the length of the first pressure chamber 18 is smaller than that of the second pressure chamber 19; the length of the pressure chamber is an important factor affecting the pressure difference formed in the pressure chamber; therefore, through the above-mentioned structural arrangement, it is ensured that there is a pressure difference between the insulating gas compressed by the first pressure chamber 18 and the second pressure chamber 19.

[0043] like Figure 5 and Figure 6 As shown, Figure 5 and Figure 6 All of them are assembly structures of the air chamber piston 10; wherein, one or more one-way valve plates and corresponding air flow channels are arranged on the air chamber piston 10. Each one-way valve plate is axially guided and limited by multiple guide rods fixedly connected to the one-way valve seat. Figure 5 As shown, there are two one-way valve discs, namely a first one-way valve disc 12 and a second one-way valve disc 11; wherein the first one-way valve disc 12 and the second one-way valve disc 11 are axially guided and limited by a first guide rod 26 and a second guide rod 25 respectively. Figure 6 As shown, it is a one-way valve disc, namely, a one-way valve disc 24; the one-way valve disc 24 is axially guided and limited by a guide rod 27. The pressure cylinder partition 8 is formed by a cylindrical cylinder extending from the pressure chamber piston 10 to the pressure chamber, and can be connected to the one-way valve seat pressure chamber piston 10 in an integrated or assembled manner.

[0044] like Figure 7 As shown, Figure 7It is an overall structure of a pressure relief valve; wherein, the first pressure relief valve seat 7 and the second pressure relief valve seat 6 are correspondingly provided with the first return air valve plate 4 and the second return air valve plate 5, and a cylindrical hollow guide cylinder 3 is provided between the first pressure relief valve seat 7 and the second pressure relief valve seat 6 to make way for the pressure cylinder partition 8, which can provide space for the axial movement of the pressure cylinder partition 8; a guide sleeve 28 is provided between the guide cylinder 3 or the second pressure relief valve seat 6 and the first pressure relief valve seat 7, and an exhaust hole 29 is provided on the side or end of the guide cylinder 3. The first pressure relief valve seat 7 and the second pressure relief valve seat 6 are fixed by the guide cylinder 3 fixedly connected to the two pressure relief valve seats, or fixed by other connection methods.

[0045] like Figure 8 The figure shows the structure of the return air channel on the pressure relief valve seat. The first pressure relief valve seat 7 and the second pressure relief valve seat 6 are both provided with a return air channel for gas to enter the pressure cylinder from the outside. The opening and closing of the return air channel is determined by the pressure difference on both sides of the return air valve plate. The outer diameter of the return air valve plate and the raised limit platform inside the return air valve seat form the guide structure of the return air valve plate. In this embodiment, a cylindrical baffle is provided to separate one air compression cylinder 9 into two parallel air compression cylinders, namely a first air compression chamber 18 and a second air compression chamber 19; and by designing the structure of the piston seat or the pressure relief valve seat, a pressure difference or an outlet flow rate difference is formed when the two air compression cylinders are compressed synchronously by the same piston.

[0046] like Fig. 9 and Fig.10 As shown, Fig. 9 The diagram shown is a schematic diagram of pressure difference realization; Fig.10 Shown is a schematic diagram of realizing flow velocity difference; Fig. 9 In the embodiment, by setting the first compressed air chamber 18 and the second compressed air chamber 19 to different lengths, that is, H1 and H2 are not equal, there is a difference between the pressures P1 and P2 generated, forming a pressure difference, and then entering the expansion chamber 22 to produce a vortex cooling effect; Fig.10 By setting the first compressed air chamber 18 and the second compressed air chamber 19 with through holes of different cross-sectional areas, that is, the cross-sectional area of ​​the air outlet 2 is different from the cross-sectional area of ​​the air outlet 1, the flow velocities V1 and V2 at the outlets are not equal, forming a flow velocity difference, and then entering the expansion chamber 22 to produce a vortex cooling effect, thereby improving the breaking capacity.

[0047] like Fig.11 As shown, for the small current interruption of the self-energy arc extinguishing chamber, during the opening process, the one-way valve is in an open state, and the arc extinguishing gas is mainly blown to the arc area through the expansion chamber by the pressure generated by the pressure cylinder. This patent can use two pressure cylinders to generate high-pressure cold gases with different pressures, which enter the expansion chamber through the one-way valve to form a vortex, cool the hot gas entering the expansion chamber due to the self-energy of the arc, and then blow the high-pressure and low-temperature gas to the fracture area (arcing area), thereby improving the small current breaking capacity.

[0048] like Fig.12As shown in the figure, for the self-energy arc extinguishing chamber high current breaking, during the opening process, the one-way valve is in an open state just before the opening point, and is closed during the arc burning process. Before the one-way valve is closed, the high-pressure cold gas of different pressures generated by the double-pressure cylinder flows into the expansion chamber to form a vortex. The vortex cools the high-pressure and high-temperature gas that enters the expansion chamber after the one-way valve is closed and the arc burns, thereby forming high-pressure and low-temperature gas in the expansion chamber, which is then blown to the fracture area to improve the high-current breaking capacity.

[0049] like Fig.13 As shown, in this embodiment, a circuit breaker with a compressed air arc extinguishing chamber is also provided, including the above-mentioned arc extinguishing device, which can improve the breaking capacity based on the same principle.

[0050] like Fig.14 As shown, specifically Fig.14 (a) is a conventional one-way valve structure. The air flow channel between the compression chamber and the expansion chamber is limited, and the air can only be pressed out from one channel; Fig.14 As shown in (b), in this embodiment, multiple screw guide structures are used for the one-way valves of the self-energy arc extinguishing chamber, the compressed air chamber and the expansion chamber. Compared with the conventional piston guide, the air flow channel between the compressed air chamber and the expansion chamber can be enlarged, the air flow transmission efficiency from the compressed air chamber to the expansion chamber during small current interruption is improved, and the small current interruption capacity is improved. The screw guide structure includes a screw and a valve plate movably connected to the screw. The valve plate can move along the axial direction of the screw to press out the insulating gas from both sides of the valve plate at the same time; the air flow transmission efficiency is improved.

[0051] In this embodiment, the one-way valve can also adopt an axial pin guide structure, which includes an axial pin and a valve plate movably connected to the axial pin. The valve plate can move axially along the axial pin, and the insulating gas is also pressed out from both sides of the valve plate at the same time. The design of the axial pin expands the structural range of the guide parts and further improves the airflow transmission efficiency.

[0052] like Fig.15 As shown, in this embodiment, for the self-energizing circuit breaker, the compressed air chamber is increased from a conventional single return air channel to a double return air channel, thereby increasing the amount of new air brought into the compressed air chamber during the closing and reclosing (i.e., opening and closing) operations, thereby enhancing the opening and breaking performance after closing.

[0053] Combination Fig.16 As shown, specifically Fig.16 (a) is a conventional pressure relief valve seat structure, the return air valve plate is guided by the outer diameter of three or more second protrusions (31), and its return air channel is limited. Fig.16As shown in (b), in this embodiment, for the self-energized arc extinguishing chamber pressure relief valve seat, three or more inner rings of the first protrusions (30) arranged inwardly are used for guidance. Compared with the conventional pressure relief valve seat structure, the return air channel of the return air valve plate in this embodiment is increased from a single channel to a double channel. During the closing and reclosing (i.e., opening and closing) operations, the amount of fresh gas brought into the pressure chamber by closing is increased, thereby enhancing the opening and breaking performance of the opening after closing.

[0054] This embodiment also provides a circuit breaker including the arc extinguishing device, such as Figure 1 As shown, the circuit breaker includes the above-mentioned arc extinguishing device, and also includes an inner nozzle 13, a moving main contact 14, a main nozzle 15, a stationary side arc contact 16 and a stationary side main contact 17 and a moving side arc contact 23.

[0055] This embodiment provides an arc extinguishing device, the key points of which are: First, a compression chamber is divided into two parallel compression chambers through a compression cylinder partition. Through the design of the piston seat or the pressure relief valve seat structure, the two compression cylinders form a pressure difference or outlet flow rate difference under the synchronous compression of the same piston, so as to form vortex cooling and improve the breaking performance.

[0056] Second, by designing the one-way valve plate guide structure, the conventional piston guide is designed as a structure with multiple guide pins, which increases the air flow channel between the compression chamber and the expansion chamber, improves the efficiency of air flow transmission from the compression chamber to the expansion chamber during small current interruption, and improves the small current breaking capacity.

[0057] Third, by designing the return air channel of the pressure relief valve seat, the conventional single return air channel is designed as a double return air channel, which increases the amount of fresh gas brought into the compressed air chamber during the closing and reclosing operations, thereby enhancing the opening and closing performance of the opening gate after closing.

[0058] It can be seen that when the arc extinguishing device and the circuit breaker including the arc extinguishing device are used for the self-energy arc extinguishing chamber to interrupt the small current, during the opening process, the one-way valve is in an open state, and the arc extinguishing gas is mainly blown to the arc area through the expansion chamber by the pressure generated by the pressure cylinder. The present invention can utilize two pressure cylinders to generate high-pressure cold gases of different pressures, which enter the expansion chamber through the one-way valve to form a vortex, cool the hot gas entering the expansion chamber due to the self-energy of the arc, and then blow the high-pressure and low-temperature gas to the fracture, thereby improving the small current breaking capacity.

[0059] For the high-current breaking of the self-extinguishing arc chamber, during the opening process, the one-way valve is in the open state just before the opening point and is closed during the arcing process. Before the one-way valve is closed, the high-pressure cold gases of different pressures generated by the double-pressure cylinder converge into the expansion chamber to form a vortex; this vortex cools the high-pressure and high-temperature gas that enters the expansion chamber after the one-way valve is closed and the arc burns, thereby forming high-pressure and low-temperature gas in the expansion chamber, which is then blown toward the fracture area to improve the high-current breaking capacity.

[0060] In summary, the present invention provides an arc extinguishing device and a circuit breaker, which have the following advantages over existing arc extinguishing devices and circuit breakers and existing arc extinguishing measures: The arc extinguishing device is designed with two parallel compressed air chambers, and is compressed synchronously under the action of the piston rod to form a pressure difference or an outlet flow rate difference. The device can efficiently press high-pressure cold insulating gas into the fracture, thereby quickly extinguishing the arc, improving the arc extinguishing speed and efficiency, and improving the breaking performance. The different length settings of the first compressed air chamber and the second compressed air chamber and the design of through holes with different cross-sectional areas provide more adjustment space for the device, so that the pressure and flow rate of the gas can be adjusted according to actual needs, enhancing the flexibility and adaptability of the device. The one-way valve plate and the screw guide structure are set on the compressed air chamber piston to ensure the one-way flow and uniform distribution of the insulating gas, further improving the arc extinguishing effect. At the same time, the design of the guide cylinder and the guide sleeve provides a stable movement space and guide for the compressed air cylinder partition, ensuring the stable operation of the device. Finally, the design of the double return air channel improves the recycling rate of the gas, making the entire device more energy-saving and environmentally friendly. In summary, the adoption of this scheme has obvious advantages in improving the performance and reliability of the arc extinguishing device.

[0061] 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 the technical field within the technical scope disclosed by the present invention.

Claims

1. An arc extinguishing device, characterized in that: It includes two parallel-connected compression chambers; The compression chamber pistons (10) of the two compression chambers are connected to the same piston rod (2); The piston passages of the two air compression chambers are both connected to the fracture; Wherein, under the action of the piston rod (2), the two compression chambers are driven to be compressed synchronously to form a pressure difference or an outlet flow rate difference, so that the two compression chambers can press high-pressure cold insulating gas into the fracture.

2. The arc extinguishing device according to claim 1, characterized in that: The two compressed air chambers include a first compressed air chamber (18) and a second compressed air chamber (19), which are formed by separating a compressed air cylinder (9) using a compressed air cylinder partition (8); The first compressed air chamber (18) is arranged around the piston rod (2), and the second compressed air chamber (19) is arranged around the first compressed air chamber (18).

3. The arc extinguishing device according to claim 2, characterized in that: The first compressed air chamber (18) and the second compressed air chamber (19) are arranged with different lengths; or, the first piston channel (21) corresponding to the first compressed air chamber (18) and the second piston channel (20) corresponding to the second compressed air chamber (19) are arranged with through holes of different cross-sectional areas.

4. The arc extinguishing device according to claim 2, characterized in that: The first compressed air chamber (18) and the second compressed air chamber (19) are arranged with different lengths; and the first piston channel (21) corresponding to the first compressed air chamber (18) and the second piston channel (20) corresponding to the second compressed air chamber (19) are arranged with through holes of different cross-sectional areas.

5. The arc extinguishing device according to claim 2, characterized in that: The piston passages of the two air compression chambers are connected to the fracture through the expansion chamber (22); The first compressed air chamber (18) is formed by the outer wall of the piston rod (2), the compressed air chamber piston (10) located at one end of the first compressed air chamber (18), and the first pressure relief valve seat (7) located at the other end of the first compressed air chamber (18); The second compressed air chamber (19) is formed by the inner wall of the compressed air cylinder (9), a compressed air chamber piston (10) located at one end of the second compressed air chamber (19), and a second pressure relief valve seat (6) located at the other end of the second compressed air chamber (19).

6. The arc extinguishing device according to claim 5, characterized in that: One or more one-way valve plates are provided on the air compression chamber piston (10); the air compression chamber piston (10) is connected to the air compression cylinder partition plate (8) in an integrated manner or in a detachable manner.

7. The arc extinguishing device according to claim 6, characterized in that: The one-way valve plate adopts a screw guide structure or an axle pin guide structure, and both the screw guide structure and the axle pin guide structure include a valve plate, so that the insulating gas is pressed out from both sides of the valve plate at the same time.

8. The arc extinguishing device according to claim 5, characterized in that: A guide cylinder (3) is provided between the first pressure relief valve seat (7) and the second pressure relief valve seat (6), and the guide cylinder (3) is used to provide movement space for the pressure cylinder partition (8); a guide sleeve (28) is provided on the inner wall of the guide cylinder (3) for providing guidance for the pressure cylinder partition (8); and an exhaust hole (29) is provided on the side wall or end of the guide cylinder (3).

9. The arc extinguishing device according to claim 5, characterized in that: The air return passages of the two compressed air chambers adopt double air return passages.

10. A circuit breaker, characterized in that: It comprises the arc extinguishing device as described in any one of claims 1-9.

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