Arc extinguishing structure for circuit breaker

Abstract

The utility model relates to circuit breaker technical field discloses a circuit breaker arc extinguishing structure, including movable contact component, static contact component and arc extinguishing chamber, the static contact point of static contact component is located at the bottom of the entrance of arc extinguishing chamber, the movable contact point of movable contact component is located at the entrance of arc extinguishing chamber and can switch between the closing position, the opening position and the tripping position, the first arc -leading piece of extending from tripping position to the opening position is arranged in arc extinguishing chamber, the first arc -leading piece is used for when carrying critical load current, the arc produced when circuit breaker opens is introduced into arc extinguishing chamber and fastly ends burning arc, and also is used for when carrying short -circuit current, the arc produced when circuit breaker trips enters arc extinguishing chamber quickly. The circuit breaker arc extinguishing structure guarantees short -circuit breaking capacity, and also improves the performance of circuit breaker carrying critical load current breaking.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, and in particular to a circuit breaker arc extinguishing structure. Background Technology

[0002] Because direct current (DC) current lacks a zero-crossing point, extinguishing a DC arc is more difficult than extinguishing an AC arc. When breaking a short-circuit current, DC circuit breakers can generally achieve rapid interruption through instantaneous tripping due to the transient nature of the short-circuit current. However, when breaking a critical DC load current, the relatively small current and weak self-excitation magnetic field mean that the magnetic flux in the arc-extinguishing grid is insufficient to draw the arc into the arc-extinguishing chamber. This process often results in overvoltage and excessively long arcing time, causing severe burn-out of the moving and stationary contacts. Existing circuit breakers struggle to handle both situations simultaneously and require further optimization. Utility Model Content

[0003] Based on the above, the purpose of this utility model is to provide a circuit breaker arc extinguishing structure that ensures short-circuit interruption while optimizing the performance of breaking critical DC load current.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A circuit breaker arc-extinguishing structure includes a moving contact assembly, a stationary contact assembly, and an arc-extinguishing chamber, wherein:

[0006] The stationary contact of the stationary contact assembly is located at the bottom of the inlet of the arc-extinguishing chamber;

[0007] The moving contact of the moving contact assembly is located at the entrance of the arc-extinguishing chamber and can switch between the closed position, the open position and the trip position. When the moving contact is in the closed position, it abuts against the stationary contact. When the moving contact is in the trip position, it is located at the top of the entrance of the arc-extinguishing chamber. When the moving contact is in the open position, it is located between the closed position and the trip position.

[0008] The arc-extinguishing chamber is equipped with a first arc-initiating plate extending from the tripped position to the open position. The first arc-initiating plate is used to introduce the arc generated by the circuit breaker tripping into the arc-extinguishing chamber and quickly end the arcing when carrying critical load current. It is also used to allow the arc generated by the circuit breaker tripping to quickly enter the arc-extinguishing chamber when carrying short-circuit current.

[0009] As an alternative, a second arc-inducing plate extending into the arc-extinguishing chamber is provided at the stationary contact. The arc-extinguishing chamber includes two parallel partitions arranged at intervals. Between the two partitions, a number of arc-extinguishing grid plates are arranged in a stacked and spaced manner between the second arc-inducing plate and the first arc-inducing plate. Each arc-extinguishing grid plate is arranged radially around the closing position, the opening position, and the tripping position.

[0010] As an alternative, the arc-extinguishing grid includes a first grid and a second grid. The first grid is U-shaped, and multiple first grids are arranged from the second arc-inducing plate to the first arc-inducing plate and face the moving contact assembly. Multiple second grids are arranged from the first arc-inducing plate to the second arc-inducing plate and face the stationary contact assembly.

[0011] As an alternative, a first arc-blocking cover is provided on the inner sidewall of each of the two partitions. The first arc-blocking cover has several slots, and the two arms of each first grid plate are inserted into the corresponding slots.

[0012] As an alternative, the moving contact assembly includes a moving contact that extends between the two first arc-blocking shields and oscillates relative to the stationary contact assembly, with the moving contact point located at the end of the moving contact.

[0013] As an optional solution, each arc-extinguishing grid plate has positioning protrusions on both sides, and the partition plate has slots corresponding to each positioning protrusion.

[0014] As an alternative, the stationary contact assembly includes a stationary contact disposed at the bottom of the arc-extinguishing chamber, a stationary contact point and a second arc-starting plate respectively disposed on the stationary contact, and a second arc-blocking cover disposed between the stationary contact and the arc-extinguishing chamber, the second arc-blocking cover having a window that exposes the stationary contact point and the second arc-starting plate.

[0015] As an optional solution, an arc-blocking plate is provided between the second arc-inducing plate and the stationary contact.

[0016] The beneficial effects of this utility model are:

[0017] The arc-extinguishing structure of this circuit breaker optimizes the shape of the conventional arc-initiating piece. The first arc-initiating piece helps the circuit breaker to introduce the arc into the arc-extinguishing chamber when it is in the open state, so that the circuit breaker can end the arc in a shorter time, reduce the burning of the moving and stationary contacts, and at the same time, allow the arc generated in the tripping state to enter the arc-extinguishing chamber as soon as possible, so as to help the circuit breaker to break the circuit quickly. Thus, it not only ensures the short-circuit breaking capacity, but also improves the circuit breaker's performance in breaking critical load currents. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the arc-extinguishing structure of the circuit breaker provided in this embodiment of the present invention in the open state;

[0019] Figure 2 This is a schematic diagram of the arc-extinguishing structure of the circuit breaker provided in this embodiment of the present invention in the tripped state;

[0020] Figure 3 This is a schematic diagram of the arc-extinguishing chamber in the arc-extinguishing structure of the circuit breaker provided in this embodiment of the utility model;

[0021] Figure 4 This is an exploded view of the arc-extinguishing chamber in the arc-extinguishing structure of the circuit breaker provided in this embodiment of the utility model;

[0022] Figure 5 This is a schematic diagram of the stationary contact assembly in the arc-extinguishing structure of the circuit breaker provided in this embodiment of the utility model.

[0023] In the attached image:

[0024] 1. Moving contact assembly; 11. Moving contact; 12. Moving contact;

[0025] 2. Stationary contact assembly; 21. Stationary contact; 22. Second arc-starting plate; 23. Stationary contact; 24. Second arc-blocking cover; 241. Window; 25. Arc-blocking plate;

[0026] 3. Arc extinguishing chamber; 31. First arc-starting plate; 32. Partition plate; 321. Bayonet; 33. Arc extinguishing grid plate; 331. First grid plate; 332. Second grid plate; 333. Positioning protrusion; 34. First arc-blocking cover; 341. Slot. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0028] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0031] Furthermore, the terms "first" and "second" are merely used to distinguish between different terms in description and do not have any special meaning.

[0032] Please see Figures 1 to 5 This embodiment provides a circuit breaker arc-extinguishing structure, including a moving contact assembly 1, a stationary contact assembly 2, and an arc-extinguishing chamber 3, wherein:

[0033] The stationary contact 21 of the stationary contact assembly 2 is located at the bottom of the inlet of the arc-extinguishing chamber 3;

[0034] The moving contact 11 of the moving contact assembly 1 is located at the entrance of the arc-extinguishing chamber 3 and can switch between the closed position, the open position and the trip position. When the moving contact 11 is in the closed position, it abuts against the stationary contact 21. When the moving contact 11 is in the trip position, it is located at the top of the entrance of the arc-extinguishing chamber 3. When the open position is located between the closed position and the trip position.

[0035] The arc-extinguishing chamber 3 is provided with a first arc-inducing piece 31 extending from the tripped position to the open position. The first arc-inducing piece 31 is used to introduce the arc generated by the circuit breaker tripping into the arc-extinguishing chamber 3 and quickly end the arcing when carrying critical load current. It is also used to make the arc generated by the circuit breaker tripping quickly enter the arc-extinguishing chamber 3 when carrying short-circuit current.

[0036] Therefore, by optimizing the shape of the first arc-inducing piece 31, the circuit breaker can introduce the arc into the arc-extinguishing chamber 3 when it is in the open state, so that the circuit breaker can end the arc in a shorter time, reduce the burn-out of the moving contact 12 and the stationary contact 23, and at the same time, allow the arc generated in the trip state to enter the arc-extinguishing chamber 3 as soon as possible, so as to help the circuit breaker break the circuit as quickly as possible. Thus, it not only ensures the short-circuit breaking capacity, but also improves the circuit breaker's performance in breaking critical load currents.

[0037] In some embodiments, a second arc-inducing plate 22 extending into the interior of the arc-extinguishing chamber 3 is provided at the stationary contact 21. The arc-extinguishing chamber 3 includes two parallel spaced partitions 32. Between the two partitions 32, a plurality of arc-extinguishing grid plates 33 are arranged in a stacked and spaced manner between the second arc-inducing plate 22 and the first arc-inducing plate 31. Each arc-extinguishing grid plate 33 is arranged radially around the closing position, the opening position and the tripping position, thereby ensuring the arc-extinguishing capability of the arc-extinguishing chamber 3 and realizing high-voltage DC interruption.

[0038] Specifically, the arc-extinguishing grid 33 includes a first grid 331 and a second grid 332. The first grid 331 is U-shaped, and multiple first grids 331 are arranged from the second arc-inducing plate 22 toward the first arc-inducing plate 31 and facing the moving contact assembly 1. Multiple second grids 332 are arranged from the first arc-inducing plate 31 toward the second arc-inducing plate 22 and facing the stationary contact assembly 2. Only two types of arc-extinguishing grids 33 are needed here, which can significantly reduce costs.

[0039] Furthermore, a first arc-blocking cover 34 is provided on the inner sidewall of each of the two partitions 32. The first arc-blocking cover 34 has a plurality of slots 341, and the two arms of each first grid plate 331 are inserted into the corresponding slots 341.

[0040] The first arc-blocking cover 34 is fixed to the partition plate 32 with screws. The slot 341 ensures that each first grid plate 331 is accurately and reliably assembled, ensuring that the spacing and angle of each first grid plate 331 meet the design requirements and guarantee the arc-extinguishing effect.

[0041] Optionally, the moving contact assembly 1 includes a moving contact 12 that extends between the two first arc-blocking shields 34 and swings relative to the stationary contact assembly 2, with the moving contact point 11 located at the end of the moving contact 12.

[0042] In some embodiments, each arc-extinguishing grid plate 33 is provided with positioning protrusions 333 on both sides, and the partition plate 32 is provided with slots 321 corresponding to each positioning protrusion 333. The positioning protrusions 333 are riveted and fixed to the slots 321 to achieve reliable fixing of the arc-extinguishing grid plate 33.

[0043] Optionally, the stationary contact assembly 2 includes a stationary contact 23 disposed at the bottom of the arc-extinguishing chamber 3, a stationary contact 21 and a second arc-starting piece 22 respectively disposed on the stationary contact 23, and a second arc-blocking cover 24 disposed between the stationary contact 23 and the arc-extinguishing chamber 3, and a window 241 is provided on the second arc-blocking cover 24 to expose the stationary contact 21 and the second arc-starting piece 22.

[0044] Furthermore, an arc-blocking plate 25 is provided between the second arc-inducing plate 22 and the stationary contact 23.

[0045] In summary, the arc-extinguishing structure of this circuit breaker has the following advantages:

[0046] 1) The large number of arc-extinguishing grid plates 33 facilitates high-voltage DC interruption;

[0047] 2) The arc-extinguishing grid plate 33 is designed to use only two types, which greatly reduces the cost and installation difficulty;

[0048] 3) While ensuring short-circuit interruption, the performance of critical load current interruption has been optimized.

[0049] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A circuit breaker arc-extinguishing structure, characterized in that, It includes a moving contact assembly (1), a stationary contact assembly (2), and an arc-extinguishing chamber (3), wherein: The stationary contact (21) of the stationary contact assembly (2) is located at the bottom of the inlet of the arc-extinguishing chamber (3); The moving contact (11) of the moving contact assembly (1) is located at the entrance of the arc-extinguishing chamber (3) and can be switched between the closed position, the open position and the tripped position. When the moving contact (11) is in the closed position, it abuts against the stationary contact (21). When the moving contact (11) is in the tripped position, it is located at the top of the entrance of the arc-extinguishing chamber (3). The open position is located between the closed position and the tripped position. The arc-extinguishing chamber (3) is provided with a first arc-inducing piece (31) extending from the tripping position to the opening position. The first arc-inducing piece (31) is used to introduce the arc generated by the circuit breaker tripping into the arc-extinguishing chamber (3) and quickly end the arc when carrying critical load current. It is also used to make the arc generated by the circuit breaker tripping quickly enter the arc-extinguishing chamber (3) when carrying short-circuit current.

2. The circuit breaker arc-extinguishing structure according to claim 1, characterized in that, A second arc-inducing plate (22) extending into the arc-extinguishing chamber (3) is provided at the stationary contact (21). The arc-extinguishing chamber (3) includes two parallel partitions (32) arranged at intervals. Between the two partitions (32) are a plurality of arc-extinguishing grid plates (33) stacked and arranged at intervals between the second arc-inducing plate (22) and the first arc-inducing plate (31). Each arc-extinguishing grid plate (33) is arranged radially around the closing position, the opening position and the tripping position.

3. The circuit breaker arc-extinguishing structure according to claim 2, characterized in that, The arc-extinguishing grid (33) includes a first grid (331) and a second grid (332). The first grid (331) is U-shaped. A plurality of the first grids (331) are arranged from the second arc-inducing plate (22) toward the first arc-inducing plate (31) and face the moving contact assembly (1). A plurality of the second grids (332) are arranged from the first arc-inducing plate (31) toward the second arc-inducing plate (22) and face the stationary contact assembly (2).

4. The circuit breaker arc-extinguishing structure according to claim 3, characterized in that, The inner walls of the two partitions (32) are respectively provided with a first arc shield (34), and the first arc shield (34) is provided with a plurality of slots (341), and the two arms of each first grid plate (331) are inserted into the corresponding slot (341).

5. The circuit breaker arc-extinguishing structure according to claim 4, characterized in that, The moving contact assembly (1) includes a moving contact (12) that extends between the two first arc shields (34) and swings relative to the stationary contact assembly (2), with the moving contact point (11) located at the end of the moving contact (12).

6. The circuit breaker arc-extinguishing structure according to claim 2, characterized in that, Each of the arc-extinguishing grid plates (33) has a positioning protrusion (333) on both sides, and the partition plate (32) has a slot (321) corresponding to each positioning protrusion (333).

7. The circuit breaker arc-extinguishing structure according to claim 2, characterized in that, The stationary contact assembly (2) includes a stationary contact (23) disposed at the bottom of the arc-extinguishing chamber (3), the stationary contact point (21) and the second arc-starting plate (22) are respectively disposed on the stationary contact (23), and a second arc-blocking cover (24) is disposed between the stationary contact (23) and the arc-extinguishing chamber (3). The second arc-blocking cover (24) has a window (241) that exposes the stationary contact point (21) and the second arc-starting plate (22).

8. The circuit breaker arc-extinguishing structure according to claim 7, characterized in that, An arc-blocking plate (25) is provided between the second arc-inducing plate (22) and the stationary contact (23).

Images