Arc extinguish chamber and circuit breaker

Abstract

The invention relates to the technical field of arc extinguishing devices, in particular to an arc extinguishing chamber and a circuit breaker. The arc extinguish chamber comprises a static contact seat and a moving contact seat which are arranged at an interval, the static contact seat and the moving contact seat are fixedly connected through an insulating supporting seat, a moving arc contact and a nozzle are arranged in the moving contact seat, the static contact seat is cylindrical, one end of the static contact seat far away from the moving contact seat is provided with a support, the center of the support is provided with a static arc contact seat, and the static arc contact seat is connected with the nozzle. A static arc contact is arranged in the static arc contact base, and a gas blocking cover is arranged on the side, facing the nozzle, of the support and used for blocking high-temperature ionization gas sprayed out of the nozzle. According to the invention, the gas blocking cover is arranged to effectively prevent high-temperature ionized gas from ablating the bracket at the bottom of the static contact seat.

Description

Technical Field

[0001] This invention relates to the field of arc extinguishing device technology, and in particular to an arc extinguishing chamber and a circuit breaker. Background Technology

[0002] Arc-extinguishing chambers are the core components of circuit breakers. Currently, high-voltage self-energized arc-extinguishing chambers that use sulfur hexafluoride gas as the arc-extinguishing and breaking medium have good insulation and reliability.

[0003] For example, Chinese invention patent CN109935495B discloses an insulating auxiliary structure for an arc-extinguishing chamber. This insulating auxiliary structure includes a moving contact seat and a stationary contact seat arranged at intervals, and an insulating support seat connecting the moving contact seat and the stationary contact seat. The stationary contact seat is a cylindrical structure, and its end face away from the moving contact seat is a fixed plate. A stationary arc contact seat with an inward protrusion is provided at the center of the fixed plate. A stationary arc contact is provided inside the stationary arc contact seat. An exhaust pipe is provided inside the stationary contact seat. The exhaust pipe is movably sealed with the nozzle. The stationary arc contact is located inside the exhaust pipe and is opposite to the moving arc contact. A stationary main contact is provided inside the stationary contact seat near the moving contact seat. The stationary main contact is located outside the exhaust pipe and opposite to the moving main contact. The moving main contact is located inside the moving contact seat. The moving contact seat is specifically a pressure cylinder. The insulating support seat is a tubular structure with open ends, which is connected to the stationary contact seat and the pressure cylinder respectively. The insulating support seat is fitted onto the nozzle, forming an expansion chamber between the insulating support seat and the nozzle.

[0004] In this arc-extinguishing chamber insulation auxiliary structure, an electric arc is generated when the moving and stationary arc contacts separate. The electric arc heats the gas in the expansion chamber, causing the gas in the expansion chamber to heat up rapidly. When the stationary arc contact detaches from the throat of the nozzle, the high-temperature ionized gas is ejected from the nozzle and sprayed along the exhaust pipe onto the fixed plate at the bottom of the stationary contact seat. Because the fixed plate at the bottom of the stationary contact seat obstructs the high-temperature ionized gas, the fixed plate at the bottom of the stationary contact seat is severely ablated. Summary of the Invention

[0005] The purpose of this invention is to provide an arc-extinguishing chamber that solves the technical problem in the prior art where the high-temperature ionized gas in the expansion chamber is ejected through the nozzle and flows through the bottom of the stationary contact seat, causing severe erosion of the bottom fixing plate of the stationary contact seat; at the same time, the purpose of this invention is also to provide a circuit breaker using the above-mentioned arc-extinguishing chamber.

[0006] To achieve the above objectives, the present invention provides a technical solution for an arc-extinguishing chamber as follows:

[0007] An arc-extinguishing chamber includes stationary contact seats and moving contact seats arranged at intervals. The stationary contact seats and moving contact seats are fixedly connected by an insulating support. The moving contact seat is provided with a moving arc contact and a nozzle. The stationary contact seat is cylindrical, and a support is provided at one end away from the moving contact seat. The stationary arc contact seat is located at the center of the support, and a stationary arc contact is provided inside the stationary arc contact seat. A gas baffle is provided on the side of the support facing the nozzle to block the high-temperature ionized gas ejected from the nozzle.

[0008] Beneficial Effects: This invention represents an improvement upon existing arc-extinguishing chambers. It primarily improves upon existing ones by installing a baffle on the side of the support at the bottom of the stationary contact seat facing the nozzle. This baffle blocks the high-temperature ionized gas sprayed from the nozzle onto the support at the bottom of the stationary contact seat, preventing it from burning the support. Specifically, when the arc-extinguishing chamber opens or closes, an electric arc is generated between the moving and stationary arc contacts. This arc heats the gas in the expansion chamber. When the stationary arc contact moves away from the nozzle until the nozzle is opened, the high-temperature ionized gas in the expansion chamber is rapidly ejected through the nozzle. As it flows through the stationary contact seat, it is blocked by the baffle on the side of the support facing the nozzle, thus preventing the support at the bottom of the stationary contact seat from burning.

[0009] Furthermore, the air baffle has an H-shaped structure, including two spaced upper arms, two spaced lower arms, and a middle cross arm located between the two upper arms and the two lower arms. The middle cross arm has a central through hole for avoiding the static arc contact seat.

[0010] Furthermore, the side of the air baffle facing the nozzle is provided with an air guiding slope to guide the gas sprayed from the nozzle obliquely backward.

[0011] Furthermore, the air guide slope is formed by gradually decreasing the wall thickness at the corresponding position of the air baffle.

[0012] Furthermore, the end faces of the two upper arms and two lower arms are arc-shaped structures that mate with the stationary contact seat.

[0013] Furthermore, the two upper arms, the two lower arms, and the two ends of the middle cross arm are provided with flanged covers along the axial direction of the central through hole. The flanged covers are fastened to the bracket at the bottom of the stationary contact seat.

[0014] Furthermore, the air deflector is made of PTFE material.

[0015] Furthermore, an intermediate contact and a static pressure sleeve are sequentially fitted onto the static arc contact head, and the gas guide cover and the intermediate contact are press-fitted onto the static arc contact seat through the static pressure sleeve.

[0016] Furthermore, the static pressure sleeve and the static arc contact seat are connected by an interference fit or a threaded connection.

[0017] To achieve the above objectives, the present invention provides a technical solution for a circuit breaker as follows:

[0018] A circuit breaker includes a circuit breaker body and an arc-extinguishing chamber. The arc-extinguishing chamber includes stationary contact seats and moving contact seats arranged at intervals. The stationary contact seats and moving contact seats are fixedly connected by an insulating support. The moving contact seat is provided with a moving arc contact and a nozzle. The stationary contact seat is cylindrical, and a support is provided at one end away from the moving contact seat. The stationary arc contact seat is located at the center of the support, and a stationary arc contact is provided inside the stationary arc contact seat. A gas baffle is provided on the side of the support facing the nozzle to block the high-temperature ionized gas ejected from the nozzle.

[0019] Beneficial effects: This invention is an improvement on existing circuit breakers. The main improvement is that a gas baffle is installed on the side of the bottom support of the stationary contact seat of the arc-extinguishing chamber facing the nozzle. This prevents the high-temperature ionized gas generated during opening and closing from burning the support at the bottom of the stationary contact seat, thereby protecting the arc-extinguishing chamber from damage and extending the service life of the circuit breaker.

[0020] Furthermore, the air baffle has an H-shaped structure, including two spaced upper arms, two spaced lower arms, and a middle cross arm located between the two upper arms and the two lower arms. The middle cross arm has a central through hole for avoiding the static arc contact seat.

[0021] Furthermore, the side of the air baffle facing the nozzle is provided with an air guiding slope to guide the gas sprayed from the nozzle obliquely backward.

[0022] Furthermore, the air guide slope is formed by gradually decreasing the wall thickness at the corresponding position of the air baffle.

[0023] Furthermore, the end faces of the two upper arms and two lower arms are arc-shaped structures that mate with the stationary contact seat.

[0024] Furthermore, the two upper arms, the two lower arms, and the two ends of the middle cross arm are provided with flanged covers along the axial direction of the central through hole. The flanged covers are fastened to the bracket at the bottom of the stationary contact seat.

[0025] Furthermore, the air deflector is made of PTFE material.

[0026] Furthermore, an intermediate contact and a static pressure sleeve are sequentially fitted onto the static arc contact head, and the gas guide cover and the intermediate contact are press-fitted onto the static arc contact seat through the static pressure sleeve.

[0027] Furthermore, the static pressure sleeve and the static arc contact seat are connected by an interference fit or a threaded connection. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of an embodiment of the arc-extinguishing chamber of the present invention;

[0029] Figure 2 for Figure 1 A schematic diagram of the structure of the center air shroud.

[0030] In the diagram: 1. Stationary contact seat; 2. Bracket; 3. Stationary arc contact seat; 4. Stationary arc contact; 5. Exhaust pipe; 6. Nozzle; 7. Moving arc contact; 8. Stationary main contact; 9. Moving main contact; 10. Moving contact seat; 11. Insulating support seat; 12. Air baffle; 13. Center perforation; 14. Clearance groove; 15. Moving connecting rod; 16. Upper support arm; 17. Lower support arm; 18. Flanged cover; 19. Intermediate contact; 20. Static pressure sleeve; 21. Position 1; 22. Position 2; 23. Position 3; 24. Expansion chamber; 25. Air guide slope; 26. Arc surface structure. Detailed Implementation

[0031] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0032] The present invention provides an arc-extinguishing chamber that addresses the problem that during the opening and closing process of the arc-extinguishing chamber, an electric arc is generated between the stationary and moving arc contacts. This arc heats the gas inside the expansion chamber, producing a large amount of high-temperature ionized gas. When the stationary arc contact does not block the nozzle, the high-temperature ionized gas is ejected through the nozzle and sprayed along the exhaust pipe onto the support at the bottom of the stationary contact seat, causing severe ablation of the support.

[0033] The main concept of this invention is to design a gas baffle on the side of the bottom support of the stationary contact seat facing the nozzle, which can effectively shield the bottom support of the stationary contact seat from the ablation of a large amount of high-temperature ionized gas generated by the arc heating when the arc-extinguishing chamber is closed and opened.

[0034] Based on the above concept, the basic solution of the present invention is: a baffle is provided on the side of the bracket at the bottom of the static contact seat of the arc extinguishing chamber facing the nozzle, and the baffle is used to block the high-temperature ionized gas ejected from the nozzle to prevent the bracket from being burned.

[0035] The following examples illustrate this:

[0036] This invention provides an arc-extinguishing chamber, such as... Figure 1As shown, it includes a stationary end portion and a moving end portion, as well as an insulating support base 11 connecting the moving end portion and the stationary end portion. The stationary end portion includes a stationary arc contact 4, an exhaust pipe 5, and a stationary main contact 8 disposed in the stationary contact base 1. The moving end portion includes a moving arc contact 7, a moving main contact 9, and a nozzle 6 disposed in the moving contact base 10. The assembly relationship of their internal structures is all prior art and will not be described in detail here. The stationary contact seat 1 is cylindrical, with a support 2 at the end furthest from the moving contact seat 10. A stationary arc contact seat 3 is located at its center. The stationary arc contact seat 3 is an inwardly convex tubular structure, and a stationary arc contact 4 is disposed within it. The stationary arc contact 4 extends into the nozzle 6, opposite the moving arc contact 7. The insulating support 11 is a cylindrical tube open at both ends, with both ends fixed to the stationary contact seat 1 and the moving contact seat 10 respectively by bolts. When the stationary arc contact 4 and the moving arc contact 7 come into contact and separate, an electric arc is generated. This electric arc heats the gas in the expansion chamber 24, producing… A large amount of high-temperature ionized gas is generated. When the stationary arc contact 4 is at position 23, a large amount of high-temperature ionized gas accumulates in the expansion chamber 24. When the stationary arc contact 4 gradually moves away from the moving arc contact 7 and is at positions 22 and 21, the high-temperature ionized gas is ejected from the nozzle 6. When it flows through the support 2 at the bottom of the stationary contact seat 1, it is blocked by the gas baffle 12 set on the side of the support 2 facing the nozzle 6. The gas baffle 12 is made of PTFE material. The heat resistance of this material can effectively protect the support 2 from being burned by the high-temperature ionized gas.

[0037] This application provides a preferred embodiment, such as... Figure 2 As shown, the baffle 12 has an H-shaped structure, including two spaced upper arms 16 and two spaced lower arms 17, and a middle cross arm located between the two upper arms 16 and the two lower arms 17. The middle cross arm has a central through hole for avoiding the static arc contact seat 3. In this embodiment, the arc-extinguishing chamber is specifically a double-acting arc-extinguishing chamber. The bottom support 2 of the static contact seat 1 has a static arc contact seat 3 and a moving connecting rod 15 passing through the bottom support 2. The double-acting arc-extinguishing chamber includes the moving connecting rod 15, the specific structure of which is prior art and will not be described in detail here. Therefore, when the baffle 12 is set on the side of the support 2 facing the nozzle 6, the baffle 12 has at least a avoidance structure for avoiding the static arc contact 3 and the moving connecting rod 15. In this embodiment, two opposing avoidance grooves 14 are formed between the two spaced upper arms 16, the two spaced lower arms 17, and the middle cross arm. One of the avoidance grooves 14 is used to avoid the moving connecting rod 15.

[0038] This application provides a preferred embodiment in which the gas baffle 12 has a guide slope 25 on the side facing the nozzle 6 to guide the gas ejected from the nozzle 6 obliquely backward. Specifically, the guide slope 25 is formed by a gradual decrease in wall thickness at corresponding positions of the gas baffle 12, that is, the wall thickness of the two spaced upper arms 16 and the two spaced lower arms 17 gradually decreases along the direction of mutual separation, so that the two spaced upper arms 16 and the two spaced lower arms 17 have the function of guiding gas to both sides. By designing the two spaced upper arms 16 and the two spaced lower arms 17 with a structure of gradually decreasing wall thickness along the direction of mutual separation, it is beneficial to guide the high-temperature ionized gas to both sides of the gas baffle 12, thereby reducing the ablation of the center of the gas baffle 12 by the high-temperature ionized gas.

[0039] This application provides a preferred embodiment, such as... Figure 2 As shown, the end faces of the two upper support arms 16 and the two lower support arms 17 are arc-shaped structures 26 that cooperate with the stationary contact seat 1. They are used to cooperate with the inner wall of the stationary contact seat 1, so that the air baffle 12 can better adapt to the structure of the bracket 2 and the stationary contact seat 1, thereby achieving a better shielding effect.

[0040] This application provides a preferred embodiment, such as... Figure 2 As shown, the two upper support arms 16, the two lower support arms 17, and both ends of the middle cross arm are provided with flanged covers 18 along the axial direction of the central through hole 13. There are two flanged covers 18, which are respectively arranged on the outer surfaces of the two support arms. Each flanged cover 18 has a central arc segment and rectangular segments at both ends to adapt to the structure of the stationary contact seat 1 and the bracket 2. The flanged covers 18 are fastened to the bracket 2 at the bottom of the stationary contact seat 1. By designing flanged covers 18 on both sides of the gas guide shroud 12 and fastening the flanged covers 18 to the bracket 2, the bracket 2 is fully shielded. When high-temperature ionized gas passes between the bracket 2 and the stationary contact seat 1, the side of the bracket 2 can be effectively prevented from being burned.

[0041] This application provides a preferred embodiment, such as... Figure 1 As shown, the stationary arc contact 4 is sequentially fitted with an intermediate contact 19 and a static pressure sleeve 20. The gas guide shroud 12 and the intermediate contact 19 are press-fitted onto the stationary arc contact seat 3 via the static pressure sleeve 20. In this embodiment, the intermediate contact 19 is designed to ensure conductivity between the stationary arc contact 4 and the stationary arc contact seat 3, and is press-fitted onto the stationary arc contact seat 3 via the static pressure sleeve 20, thereby ensuring more reliable conductivity at the stationary end.

[0042] This application provides a preferred embodiment in which the static pressure sleeve 20 and the static arc contact seat 3 are connected by an interference fit or a threaded connection, making the arc extinguishing device more stable and reliable.

[0043] The present invention provides another technical solution, which applies the above-mentioned arc-extinguishing chamber to a circuit breaker. The circuit breaker includes a circuit breaker body and an arc-extinguishing chamber. By setting a baffle on the side of the bottom support of the stationary contact seat in the arc-extinguishing chamber facing the nozzle, the support at the bottom of the stationary contact seat in the arc-extinguishing chamber is protected from being burned by high-temperature ionized gas, thereby extending the service life of the circuit breaker.

[0044] 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 stationary contact seats and moving contact seats arranged at intervals, the stationary contact seats and moving contact seats being fixedly connected by an insulating support, the moving contact seat containing a moving arc contact and a nozzle, the stationary contact seat being cylindrical, with a support at one end away from the moving contact seat, the stationary arc contact seat being located at the center of the support, and the stationary arc contact seat containing a stationary arc contact, characterized in that... The side of the bracket facing the nozzle is provided with a gas baffle for shielding the high-temperature ionized gas sprayed from the nozzle.

2. The arc chute of claim 1, wherein, The gas baffle is in H-shaped structure, comprising two spaced-apart upper arms, two spaced-apart lower arms and a middle cross arm between the two upper arms and the two lower arms, and a central through hole for avoiding the static arc contact seat is formed on the middle cross arm.

3. The arc chute of claim 2 wherein, The side of the gas baffle facing the nozzle is provided with a gas guide slope for guiding the gas sprayed from the nozzle to the rear side.

4. The arc chute of claim 3 wherein, The gas guide slope is formed by gradually reducing the wall thickness of the gas baffle at the corresponding position.

5. The arc chute of claim 4 wherein, The end faces of the two upper arms and the two lower arms are arc faces matched with the static contact seat.

6. The arc chute of claim 5 wherein, The sides of the two upper arms and the two lower arms and the two ends of the middle cross arm away from each other are provided with flange buckles in the axial direction of the central through hole, and the flange buckles are buckled on the bracket at the bottom of the static contact seat.

7. The arc chute defined in any one of claims 1 to 6 wherein, The gas baffle is made of PTFE material.

8. The arc chute of claim 7 wherein, The static arc contact is sequentially sleeved with an intermediate contact and a static pressure sleeve, and the gas guide baffle and the intermediate contact are pressed on the static arc contact seat through the static pressure sleeve.

9. The arc chute of claim 8 wherein, The static pressure sleeve and the static arc contact seat are connected by interference fit or threaded connection.

10. A circuit breaker comprising a circuit breaker body and an arc chute, characterized in that The structure of the arc extinguishing chamber is the arc extinguishing chamber of any one of claims 1-9.

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