An arc-extinguishing chamber and circuit breaker

Abstract

The application provides an arc-extinguishing chamber and a circuit breaker. The arc-extinguishing chamber comprises a movable contact module, a tubular piston rod and a movable contact seat. The movable contact module comprises a movable contact, a pressure cylinder connected to the movable contact and a nozzle connected to the pressure cylinder. The pressure cylinder is slidably assembled between the tubular piston rod and the movable contact seat through a guide structure. The guide structure comprises a contact finger at the front end of the movable contact seat, a T-shaped slot on the outer side surface of the front end of the tubular piston rod, a pressure cylinder guide ring and an elastic ring installed in the T-shaped slot. The arc-extinguishing chamber has excellent sealing performance, improves the arc-extinguishing capacity of the arc-extinguishing chamber, and prolongs the service life of the circuit breaker using the arc-extinguishing chamber.

Description

Technical Field

[0001] This invention relates to an arc-extinguishing chamber and a circuit breaker, belonging to the field of arc-extinguishing or arc-suppressing devices. Background Technology

[0002] Circuit breakers are among the most important devices in power systems, serving to open and close circuits and interrupt current flow. When necessary, they can also automatically disconnect circuits under the action of protective devices to prevent short circuits. The arc-extinguishing chamber, on the other hand, limits the location of the electric arc and extinguishes it promptly, ensuring the normal disconnection of the circuit; it is a crucial component of the circuit breaker.

[0003] Chinese invention patent CN104201049A, published on December 10, 2014, discloses a pressure cylinder-main contact device and the moving end and circuit breaker arc-extinguishing chamber using the device. Its background section mentions an arc-extinguishing chamber comprising a pressure cylinder, a moving contact finger, and a rear thrust ring surface, which together form a guiding structure for the arc-extinguishing chamber. A guide ring is provided on the outer surface of the rear thrust ring surface to facilitate sliding assembly between the rear thrust ring surface and the pressure cylinder, thereby improving the horizontal guiding capability of the arc-extinguishing chamber.

[0004] However, in the arc-extinguishing chamber described in the background technology of the aforementioned invention patent, under the action of the self-weight of the pressure cylinder, the frictional force between the guide ring and the upper contact surface of the pressure cylinder body is greater than that between the lower contact surface. This ultimately leads to greater wear on the upper contact surface between the pressure cylinder and the guide ring than on the lower surface. As a result, the pressure cylinder body sinks under the action of gravity, which creates gaps in the lower part of the contact surface, reducing the airtightness of the arc-extinguishing structure and thus reducing the arc-extinguishing capacity of the arc-extinguishing chamber. Consequently, the current cannot be cut off in time, ultimately affecting the service life of the circuit breaker. Summary of the Invention

[0005] The purpose of this invention is to provide an arc-extinguishing chamber that solves the problem of poor arc-extinguishing effect caused by reduced air tightness of the air-pressurized cylinder. Simultaneously, the purpose of this invention is also to provide a circuit breaker that solves the problem of poor circuit breaker reliability and reduced service life caused by poor arc-extinguishing effect of the arc-extinguishing chamber.

[0006] To achieve the above objectives, the arc-extinguishing chamber in this invention adopts the following technical solution:

[0007] An arc-extinguishing chamber includes a stationary contact, a moving contact module, a tubular piston rod, and a moving contact seat. The moving contact module includes a moving contact, a pressure cylinder connected to the moving contact, and a nozzle connected to the pressure cylinder. The pressure cylinder is slidably assembled between the tubular piston rod and the moving contact seat. A groove is provided on the outer surface of the front end of the tubular piston rod. A C-shaped guide ring and an elastic ring are installed within the groove. The total height of the C-shaped guide ring and the elastic ring is greater than the depth of the groove. The elastic ring is located inside the C-shaped guide ring and provides support for it.

[0008] The beneficial effects of the above technical solution are as follows: the total height of the C-shaped guide ring and the elastic ring is greater than the groove depth, allowing the elastic ring to flexibly deform after the compressor cylinder is installed, maintaining a tight seal between the compressor cylinder and the tubular piston rod. During use, the compressor cylinder experiences varying degrees of wear at its upper and lower parts due to its own weight, resulting in gaps. The elastic ring, through its elastic deformation, ensures that the C-shaped guide ring remains tightly fitted to the compressor cylinder, ultimately maintaining the airtightness of the guide structure at all times. Simultaneously, the elastic ring also provides support to the compressor cylinder through its elasticity, resisting the effects of gravity and preventing longitudinal displacement of the compressor cylinder due to gravity after wear, thus ensuring precise alignment of the moving and stationary contacts. Ultimately, through these effects, the arc-extinguishing chamber maintains optimal arc-extinguishing capability at all times.

[0009] Furthermore, a limiting structure is provided inside the groove to limit the C-shaped guide ring. The limiting structure is located inside the C-shaped guide ring to ensure that the outer circumferential surface of the C-shaped guide ring is not lower than the groove edge, and the cross-sectional thickness of the elastic ring is not less than the height of the limiting structure.

[0010] The beneficial effects of the above technical solution are as follows: by setting a limiting structure, excessive pressure is prevented from being applied to the C-shaped guide ring and elastic ring by the moving contact module during the movement, which would cause the elastic ring to deform excessively and ultimately cause the C-shaped guide ring to be lower than the groove surface, affecting the horizontal guiding performance of the C-shaped guide ring and the airtightness of the pressure cylinder, thus further improving the sealing performance and guiding effect, and thus ensuring the arc extinguishing capability of the arc extinguishing chamber.

[0011] Furthermore, the limiting structure is a boss protruding from the bottom of the groove.

[0012] The beneficial effects of the above technical solution are as follows: the blocking effect can be achieved simply by machining the front end of the tubular piston rod, without the need for additional components, thus ensuring the arc extinguishing capacity of the arc extinguishing chamber with minimal manpower and material costs.

[0013] Furthermore, there are two bosses symmetrically arranged in the width direction of the groove, making the groove as a whole a T-shaped groove, and the elastic ring is installed between the two bosses.

[0014] The beneficial effects of the above technical solution are as follows: The T-slot ensures the elastic ring is positioned in the center, guaranteeing that the elastic force acts on the center of the C-shaped guide ring during elastic deformation. When the stopping structure performs its stopping function, the stopping force applied to both sides is more balanced. Overall, it avoids the generation of eccentric forces, preventing uneven force distribution between the C-shaped guide ring and the pressure cylinder, which would accelerate deformation and wear. This, in turn, improves the sealing and guiding performance of the arc-extinguishing chamber, ensuring its arc-extinguishing capability.

[0015] Furthermore, a contact finger is provided on the inner side of the front end of the moving contact seat, and the contact finger corresponds to the elastic ring in the axial direction.

[0016] The beneficial effects of the above technical solution are as follows: the contact fingers and the elastic ring cooperate with each other, and the elastic ring reduces the influence of gravity through elastic deformation, making the compression of the upper and lower contact fingers more uniform; at the same time, the center points of the contact fingers and the elastic ring cross-sections are on the same axial plane, concentrating the force point in one place and avoiding the generation of eccentric force; furthermore, the design of the contact fingers avoids direct contact between the pressure cylinder and the moving contact seat, reducing the contact area and lowering friction. Overall, wear is minimized to the greatest extent, further improving the sealing and guiding performance of the arc-extinguishing chamber and ensuring arc-extinguishing capability.

[0017] Furthermore, the moving contact passes through the tubular piston rod, and a moving contact guide ring is provided on the tubular piston rod at the passing part. The moving contact guide ring and the C-shaped guide ring are offset in the axial direction.

[0018] The beneficial effects of the above technical solution are as follows: by setting a guide ring on the sleeve part of the tubular piston rod to limit the movement of the moving contact, the number of grooves at the front end of the tubular piston rod and the number of C-shaped guide rings and elastic rings in the groove can be reduced. Multiple limiting points are formed on different planes in the axial direction in the most economical way, which improves the guiding performance of the arc-extinguishing chamber, enables the moving and stationary contacts to accurately connect and separate, and ensures the arc-extinguishing capacity of the arc-extinguishing chamber.

[0019] Furthermore, the gap between the two ends of the C-shaped guide ring is no more than 2mm.

[0020] The beneficial effects of the above technical solution are: while ensuring that the gap between the two ends of the C-shaped guide ring does not affect the airtightness of the air cylinder, the C-shaped guide ring can deform with the elastic ring, maintain the airtightness of the arc-extinguishing chamber at all times, and thus ensure the arc-extinguishing performance of the arc-extinguishing chamber.

[0021] Furthermore, the elastic ring is a rubber sealing ring.

[0022] The beneficial effects of the above technical solution are as follows: the rubber sealing ring has the characteristics of good elasticity, easy processing and low material price, which satisfies the elastic support effect in the most economical way and ensures the arc extinguishing capacity of the arc extinguishing chamber.

[0023] Furthermore, the C-shaped guide ring is a polytetrafluoroethylene (PTFE) guide ring.

[0024] The beneficial effects of the above technical solution are as follows: the surface of the polytetrafluoroethylene guide ring is smoother, which can minimize wear, prevent the air tightness of the cylinder from decreasing, and ensure the arc extinguishing capacity of the arc extinguishing chamber.

[0025] To achieve the above objectives, the circuit breaker in this invention adopts the following technical solution:

[0026] A circuit breaker includes a sealed housing and an arc-extinguishing chamber installed within the sealed housing. The arc-extinguishing chamber includes a stationary contact, a moving contact module, a tubular piston rod, and a moving contact seat. The moving contact module includes a moving contact, a pressure cylinder connected to the moving contact, and a nozzle connected to the pressure cylinder. The pressure cylinder is slidably assembled between the tubular piston rod and the moving contact seat. A groove is provided on the outer side of the front end of the tubular piston rod. A C-shaped guide ring and an elastic ring are installed in the groove. The total height of the C-shaped guide ring and the elastic ring is greater than the depth of the groove. The elastic ring is located inside the C-shaped guide ring and provides support for the C-shaped guide ring.

[0027] The beneficial effects of the above technical solution are as follows: the total height of the C-shaped guide ring and the elastic ring is greater than the groove depth, allowing the elastic ring to flexibly deform after the compressor cylinder is installed, maintaining a tight seal between the compressor cylinder and the tubular piston rod. During use, the compressor cylinder experiences varying degrees of wear at its upper and lower parts due to its own weight, resulting in gaps. The elastic ring, through its elastic deformation, ensures that the C-shaped guide ring remains tightly fitted to the compressor cylinder, ultimately maintaining the airtightness of the guide structure at all times. Simultaneously, the elastic ring also provides support to the compressor cylinder through its elasticity, resisting the effects of gravity and preventing longitudinal displacement of the compressor cylinder due to gravity after wear, thus ensuring precise alignment of the moving and stationary contacts. Ultimately, through these effects, the arc-extinguishing chamber maintains optimal arc-extinguishing capability, thereby improving the reliability of the circuit breaker and extending its service life.

[0028] Furthermore, a limiting structure is provided inside the groove to limit the C-shaped guide ring. The limiting structure is located inside the C-shaped guide ring to ensure that the outer circumferential surface of the C-shaped guide ring is not lower than the groove edge, and the cross-sectional thickness of the elastic ring is not less than the height of the limiting structure.

[0029] The beneficial effects of the above technical solution are as follows: by setting a limiting structure, excessive pressure is prevented from being applied to the C-shaped guide ring and elastic ring by the moving contact module during the movement, which would cause excessive deformation of the elastic ring and ultimately cause the C-shaped guide ring to be lower than the groove surface, affecting the horizontal guiding performance of the C-shaped guide ring and the airtightness of the pressure cylinder. This further improves the sealing performance and guiding effect, ensures the arc extinguishing capacity of the arc extinguishing chamber, and thus improves the reliability of the circuit breaker and extends the service life of the circuit breaker.

[0030] Furthermore, the limiting structure is a boss protruding from the bottom of the groove.

[0031] The beneficial effects of the above technical solution are as follows: the blocking effect can be achieved simply by machining the front end of the tubular piston rod, without the need for additional construction. This ensures the arc-extinguishing capacity of the arc-extinguishing chamber with minimal manpower and material costs, thereby improving the reliability of the circuit breaker and extending its service life.

[0032] Furthermore, there are two bosses symmetrically arranged in the width direction of the groove, making the groove as a whole a T-shaped groove, and the elastic ring is installed between the two bosses.

[0033] The beneficial effects of the above technical solution are as follows: The T-slot ensures the elastic ring is positioned in the center, guaranteeing that the elastic force acts on the center of the C-shaped guide ring during elastic deformation. When the stopping structure applies force, the stopping force applied to both sides is more balanced. Overall, it avoids the generation of eccentric forces, preventing uneven force distribution between the C-shaped guide ring and the pressure cylinder, which would accelerate deformation and wear. This, in turn, improves the sealing and guiding performance of the arc-extinguishing chamber, ensures its arc-extinguishing capability, enhances the reliability of the circuit breaker, and extends its service life.

[0034] Furthermore, a contact finger is provided on the inner side of the front end of the moving contact seat, and the contact finger corresponds to the elastic ring in the axial direction.

[0035] The beneficial effects of the above technical solution are as follows: the contact fingers and the elastic ring cooperate with each other, and the elastic ring reduces the influence of gravity through elastic deformation, making the compression of the upper and lower contact fingers more uniform; at the same time, the center points of the contact fingers and the elastic ring cross-sections are on the same axial plane, concentrating the force point in one place and avoiding the generation of eccentric force; furthermore, the design of the contact fingers avoids direct contact between the pressure cylinder and the moving contact seat, reducing the contact area and lowering friction. Overall, it minimizes wear, further improves the sealing and guiding performance of the arc-extinguishing chamber, ensures arc-extinguishing capability, allows the current to be disconnected in a timely manner, improves the reliability of the circuit breaker, and extends the service life of the circuit breaker.

[0036] Furthermore, the moving contact passes through the tubular piston rod, and a moving contact guide ring is provided on the tubular piston rod at the passing part. The moving contact guide ring and the C-shaped guide ring are offset in the axial direction.

[0037] The beneficial effects of the above technical solution are as follows: by setting a guide ring on the sleeve part of the tubular piston rod to limit the movement of the moving contact, the number of grooves at the front end of the tubular piston rod and the number of C-shaped guide rings and elastic rings in the groove can be reduced. Multiple limiting points are formed on different planes in the axial direction in the most economical way, which improves the guiding performance of the arc-extinguishing chamber, enables precise docking and separation of the moving and stationary contacts, ensures the arc-extinguishing capacity of the arc-extinguishing chamber, extends the service life of the circuit breaker, and improves the reliability of the circuit breaker.

[0038] Furthermore, the gap between the two ends of the C-shaped guide ring is no more than 2mm.

[0039] The beneficial effects of the above technical solution are as follows: while ensuring that the gap between the two ends of the C-shaped guide ring does not affect the airtightness of the air-pressurized cylinder, the C-shaped guide ring can deform with the elastic ring, maintain the airtightness of the arc-extinguishing chamber at all times, thereby ensuring the arc-extinguishing performance of the arc-extinguishing chamber, improving the reliability of the circuit breaker, and extending the service life of the circuit breaker.

[0040] Furthermore, the elastic ring is a rubber sealing ring.

[0041] The beneficial effects of the above technical solution are as follows: the rubber sealing ring has the characteristics of good elasticity, easy processing and low material price, which satisfies the elastic support effect in the most economical way, ensures the arc extinguishing capacity of the arc extinguishing chamber, improves the reliability of the circuit breaker and extends the service life of the circuit breaker.

[0042] Furthermore, the C-shaped guide ring is a polytetrafluoroethylene (PTFE) guide ring.

[0043] The beneficial effects of the above technical solution are as follows: the surface of the polytetrafluoroethylene guide ring is smoother, which can minimize wear, prevent the air tightness of the cylinder from decreasing, ensure the arc extinguishing capacity of the arc extinguishing chamber, improve the reliability of the circuit breaker, and extend the service life of the circuit breaker. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the arc-extinguishing chamber in Embodiment 1 of the circuit breaker of the present invention;

[0045] Figure 2 for Figure 1 Enlarged view of the structure at point A in the middle.

[0046] In the diagram: 1. Nozzle; 2. Moving contact; 3. Compressor cylinder; 4. Tubular piston rod; 5. Moving contact seat; 6. Compressor cylinder guide ring; 7. Elastic ring; 8. Contact finger; 9. T-slot; 10. Moving contact guide ring; 11. T-slot stepped surface; 12. Gas passage; 13. Contact finger groove; 14. Stationary contact. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0049] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any actual relationship or order between these entities or operations. Furthermore, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0051] Example 1 of the implementation of the circuit breaker in this invention:

[0052] Implementation example 1 of circuit breaker Figure 1 , Figure 2 As shown, the circuit breaker includes an arc-extinguishing chamber, which includes a stationary contact 14, a moving contact module, a tubular piston rod 4, and a moving contact seat 5.

[0053] The moving contact module includes a nozzle 1, a moving contact 2, and a pressure cylinder 3. The nozzle 1 is fixed to the side of the pressure cylinder 3 near the stationary contact 14. The pressure cylinder 3 is a hollow barrel-shaped structure that is closed on the side near the stationary contact 14 and open on the side away from the stationary contact 14. A gas passage 12 is also provided on the side of the pressure cylinder 3 near the stationary contact 14. The tubular piston rod 4 is sleeved inside the cylinder body through the open structure on the side away from the stationary contact 14, and is slidably assembled with the tubular piston rod 4. The moving contact 2 passes through the inside of the tubular piston rod 4 and is connected to the transmission structure outside the arc extinguishing chamber. At the same time, the moving contact 2 is fixedly connected inside the pressure cylinder 3, so that the pressure cylinder 3 can move horizontally with the moving contact 2. The inner wall of the compression cylinder 3 is in close contact with the outer side of the front end of the tubular piston rod 4. When the moving contact 2 moves horizontally away from the stationary contact 14, the compression cylinder 3 moves with the moving contact 2, reducing the space inside the cylinder and compressing the gas, which is eventually discharged from the gas passage 12.

[0054] The tubular piston rod 4 has a barrel-shaped structure and is directly fixed to the outer shell of the arc-extinguishing chamber. The tubular piston rod 4 has a T-slot 9 and a moving contact guide ring 10. The moving contact guide ring 10 is located on the contact surface of the tubular piston rod 4 when the moving contact 2 and the tubular piston rod 4 are connected through a sleeve. The T-slot 9 is annular, with the narrow opening facing inwards and the wide opening facing outwards, and is located on the outer side of the front end of the tubular piston rod 4. The T-slot 9 contains an elastic ring 7 and a pressure cylinder guide ring 6. The elastic ring 7 is a rubber sealing ring, and the pressure cylinder guide ring 6 is a C-shaped guide ring made of polytetrafluoroethylene (PTFE), with a 1mm gap at the opening. The elastic ring 7 is installed in the narrow opening of the T-slot 9, and the pressure cylinder guide ring 6 is installed in the wide opening of the T-slot 9 and is located above the elastic ring 7. The T-slot stepped surface 11 forms a limiting structure. The height from the T-slot stepped surface 11 to the bottom of the narrow opening of the T-slot 9 is less than the cross-sectional height of the elastic ring 7. The depth of the wide opening of the T-slot is equal to the cross-sectional height of the pressure cylinder guide ring 6. The total cross-sectional height of the elastic ring 7 and the pressure cylinder guide ring 6 is greater than the total depth of the T-slot 9. This ensures that when the elastic ring 7 provides elastic support, the T-slot stepped surface 11 will limit the pressure cylinder guide ring 6, preventing excessive deformation of the elastic ring 7.

[0055] The moving contact seat 5 is a hollow barrel-shaped structure open at both ends. The inner side of its end closest to the stationary contact 14 is in close contact with the air cylinder 3, while the side furthest from the stationary contact 13 is fixed to the outer casing of the arc-extinguishing chamber. The moving contact seat 5 has a contact finger 8 and a contact finger groove 13. The contact finger groove 13 is annularly arranged on the inner side of the end of the moving contact seat 5, and corresponds axially to the T-slot 9. The contact finger 8 is annular and installed within the contact finger groove. After installation, the contact finger 8 corresponds axially to the elastic ring.

[0056] The stationary contact 14 is directly fixed to the outer shell of the arc-extinguishing chamber and is at the same level as the moving contact 2 to ensure precise docking.

[0057] Example 2 of the implementation of the circuit breaker of the present invention:

[0058] The difference between Implementation Example 2 and Implementation Example 1 is that the groove on the outer side of the front end of the tubular piston rod in the arc extinguishing chamber does not need to be equipped with a limiting structure. In this case, the elastic force of the elastic sealing ring needs to be increased to prevent the elastic ring from deforming excessively due to insufficient elastic force.

[0059] Example 3 of the implementation of the circuit breaker of the present invention:

[0060] The difference between Implementation Example 3 and Implementation Example 1 is that the groove on the outer side of the tubular piston rod at the front end in the arc-extinguishing chamber can also be a rectangular groove. In this case, a metal ring can be placed at the center of the bottom of the rectangular groove. The cross-sectional thickness of the metal ring is equal to the groove depth minus the guide ring thickness. In this case, the metal ring acts as a stop for the C-shaped guide ring. Two elastic rings are set on both sides of the metal ring, and their cross-sectional thickness is greater than that of the metal ring. The two elastic rings together provide elastic support for the guide ring. At this time, the contact finger should correspond to the axial position of the metal ring to ensure that the pressure cylinder is evenly stressed. No other parts need to be adjusted.

[0061] Example 4 of the implementation of the circuit breaker of the present invention:

[0062] The difference between Implementation Example 4 and Implementation Example 1 is that: the T-slots on the outer side of the front end of the tubular piston rod in the arc extinguishing chamber can also be two. Correspondingly, two elastic rings are set and located in the narrow part of the two T-slots respectively. Two C-shaped guide rings are also set and located in the wide part of the two T-slots respectively, so as to further improve the sealing and guiding performance. No other parts need to be adjusted.

[0063] Example 5 of the implementation of the circuit breaker of the present invention:

[0064] The difference between Implementation Example 5 and Implementation Example 1 is that: One boss constituting the limiting structure is set, centrally located at the bottom of the groove. In this case, two elastic rings are needed to provide elastic support for the C-shaped guide ring. The contact finger aligns with the boss position, ensuring balanced force on the air cylinder; no other adjustments are required.

[0065] Example 6 of the implementation of the circuit breaker of the present invention:

[0066] The difference between Implementation Example 6 and Implementation Example 1 is that: one boss constituting the limiting structure is set on one side of the bottom of the groove, and no other parts need to be adjusted. At this time, the elastic ring can also play the role of elastic support, thereby improving the arc extinguishing capacity of the arc extinguishing chamber.

[0067] Example 7 of the implementation of the circuit breaker of the present invention:

[0068] The difference between Implementation Example 7 and Implementation Example 1 is that the contact finger at the front end of the contact seat and the elastic ring are not aligned in the axial direction. However, they can still cooperate with the elastic ring to reduce the friction force on the cylinder.

[0069] Example 8 of the implementation of the circuit breaker of the present invention:

[0070] The difference between Implementation Example 8 and Implementation Example 1 is that the moving contact guide ring and the C-shaped guide ring are axially aligned. In this case, the length of the tubular piston rod and the moving contact can be shortened, reducing the volume of the arc-extinguishing chamber. No other parts need to be adjusted.

[0071] Example 9 of the implementation of the circuit breaker of the present invention:

[0072] The difference between Implementation Example 9 and Implementation Example 1 is that the elastic ring is set as a ring spring, and no other parts need to be adjusted.

[0073] Example 10 of the circuit breaker of the present invention:

[0074] The difference between Implementation Example 10 and Implementation Example 1 is that the thickness of the C-shaped guide ring is greater than the depth of the T-slot. In this case, the boss can still play a limiting role, and the elastic support of the elastic ring is not affected. Other parts do not need to be adjusted.

[0075] Example 11 of the circuit breaker of the present invention:

[0076] The difference between Implementation Example 11 and Implementation Example 1 is that the C-shaped guide ring is a polyimide guide ring, and no other parts need to be adjusted.

[0077] An embodiment of the arc-extinguishing chamber of the present invention: The structure of the arc-extinguishing chamber in this embodiment is the same as that in the various embodiments of the circuit breaker described above, and will not be repeated here.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. An arc-extinguishing chamber, comprising a stationary contact (14), a moving contact module, a tubular piston rod (4), and a moving contact seat (5), wherein the moving contact module comprises a moving contact (2), a pressure cylinder (3) connected to the moving contact (2), and a nozzle (1) connected to the pressure cylinder (3), wherein the pressure cylinder (3) is slidably assembled between the tubular piston rod (4) and the moving contact seat (5), characterized in that: The tubular piston rod (4) has a groove on its front outer side. A C-shaped guide ring and an elastic ring (7) are installed in the groove. The total height of the C-shaped guide ring and the elastic ring (7) is greater than the depth of the groove. The elastic ring (7) is located inside the C-shaped guide ring and supports the C-shaped guide ring. The groove has a limiting structure for limiting the C-shaped guide ring. The limiting structure is located inside the C-shaped guide ring to ensure that the outer circumferential surface of the C-shaped guide ring is not lower than the groove edge. The cross-sectional thickness of the elastic ring (7) is not less than the height of the limiting structure.

2. The arc-extinguishing chamber according to claim 1, characterized in that: The limiting structure is a boss protruding from the bottom of the groove.

3. The arc-extinguishing chamber according to claim 2, characterized in that: The bosses are two in number and are symmetrically arranged in the width direction of the groove, so that the groove is a T-shaped groove (9) and the elastic ring (7) is installed between the two bosses.

4. The arc-extinguishing chamber according to claim 3, characterized in that: The moving contact seat (5) has a contact finger (8) on the inner side of its front end, and the contact finger (8) corresponds to the elastic ring (7) in the axial direction.

5. The arc-extinguishing chamber according to claim 4, characterized in that: The moving contact (2) passes through the tubular piston rod (4), and a moving contact guide ring (10) is provided on the tubular piston rod at the passing part. The moving contact guide ring (10) and the C-shaped guide ring are offset in the axial direction.

6. The arc-extinguishing chamber according to any one of claims 1-5, characterized in that: The gap between the two ends of the C-shaped guide ring is no more than 2mm.

7. The arc-extinguishing chamber according to any one of claims 1-5, characterized in that: The elastic ring (7) is a rubber sealing ring.

8. The arc-extinguishing chamber according to any one of claims 1-5, characterized in that: The C-shaped guide ring is a polytetrafluoroethylene (PTFE) guide ring.

9. A circuit breaker, comprising a sealed housing and an arc-extinguishing chamber installed within the sealed housing, characterized in that: The arc-extinguishing chamber is the arc-extinguishing chamber as described in any one of claims 1-8.

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