Circuit breaker contact system and circuit breaker

Abstract

The utility model discloses a circuit breaker contact system and a circuit breaker, comprising a base and a bottom plate which are matched with each other, and the base and the bottom plate are respectively provided with a movable contact part and a static contact part which are correspondingly arranged. The movable contact part is provided with a partition plate used for preventing electric arc generated by opening from moving downwards from a breaking gap between the movable contact part and the static contact part in the direction deviating from an arc extinguish chamber of the circuit breaker, and the bottom plate is provided with an avoiding groove corresponding to the partition plate so that the movable contact part and the static contact part can be normally closed. And a pressure relief gap is formed between the partition plate and the avoiding groove. According to the utility model, the pressure relief gap is formed between the partition plate and the avoiding groove, so that the problems that the air pressure in the cavity is too high when the arc burns due to the arrangement of the partition plate, the arc is driven to be ejected out of the arc extinguish chamber too quickly, the arc is short-circuited outside, and the test fails can be effectively solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit breaker technical field, concretely relates to a circuit breaker contact system and circuit breaker. BACKGROUND

[0002] The contact system of the circuit breaker usually includes a shell composed of a base and a bottom plate, and a movable contact part and a static contact part arranged oppositely in the shell, and the movable contact part can rotate around a rotating shaft pin under the drive of a driving mechanism, and then contact with the static contact part to form a closed state or separate from the static contact part to form an open state, so as to make the circuit breaker connect or disconnect the main loop circuit. When the main loop circuit is rated to carry load or has an abnormal large current, the movable contact part and the static contact part will separate at the moment, and the arc burning will generate a large amount of heat, resulting in a local pressure rising instantaneously, and the high pressure will force the arc to move to a place with low pressure. In the process of opening the contact system, the movable contact part will rotate reversely to pull away from the static contact part, and then a large gap will be generated between the movable contact part and the static contact part. Thus, the arc generated at the moment of opening the contact system may move away from the arc extinguishing chamber preset above the movable contact part and the static contact part under the action of high pressure, which is not conducive to the arc entering the arc extinguishing chamber, resulting in poor arc extinguishing effect. SUMMARY

[0003] In view of the defects of the prior art, the utility model provides a circuit breaker contact system, which mainly solves the technical problem of poor arc extinguishing effect of the existing circuit breaker.

[0004] To achieve the above-mentioned purpose, the utility model is realized by the following technical scheme:

[0005] A circuit breaker contact system, comprising a base and a bottom plate cooperating with each other, a movable contact part and a static contact part arranged oppositely on the base and the bottom plate respectively, a baffle arranged on the movable contact part for preventing the arc generated by opening from moving downward from the opening gap between the movable contact part and the static contact part in a direction away from the arc extinguishing chamber of the circuit breaker, an avoiding groove provided on the bottom plate corresponding to the baffle to enable the movable contact part and the static contact part to normally close, and a pressure relief gap formed between the baffle and the avoiding groove.

[0006] Further, the minimum gap between the inner wall of the avoiding groove and the baffle is 0.6mm-1mm.

[0007] Further, the minimum gap between the inner wall of the avoiding groove and the baffle is 0.8mm.

[0008] Further, the baffle is made of PA66-GF25 material.

[0009] Furthermore, the extension length of the baffle is configured such that the end of the baffle remains within the clearance groove during the continuous burning time of the arc generated when the circuit is opened.

[0010] Furthermore, the extension length of the baffle is configured such that the end of the baffle remains within the clearance groove for 10ms during the circuit breaker's tripping operation.

[0011] Based on the same inventive concept, this utility model also provides a circuit breaker, including any of the circuit breaker contact systems described above.

[0012] The above technical solution has the following advantages or beneficial effects:

[0013] In the circuit breaker contact system and circuit breaker described in this utility model, a partition is installed on the moving contact portion. During the separation process between the moving and stationary contacts, the partition blocks the gap between them, preventing a large gap from forming. The gas pressure generated by the arc combustion cannot move downwards but can only move upwards and be ejected from the arc-extinguishing chamber. The arc, driven by the strong airflow, also moves upwards and enters the corresponding arc-extinguishing chamber, where it is divided by the grid plates, thereby extinguishing the arc. At the same time, by creating a relief groove on the base plate, the moving and stationary contacts can close normally without being restricted by the externally extending partition. A pressure relief gap is formed between the partition and the relief groove. This effectively improves the problem that the excessively high gas pressure inside the chamber during arc combustion caused by the partition can lead to the arc being ejected from the arc-extinguishing chamber too quickly, easily causing an external short circuit and making the test fail. Attached Figure Description

[0014] Figure 1 This is an exploded three-dimensional structural diagram of the circuit breaker contact system according to an embodiment of the present invention.

[0015] Figure 2 This is an exploded three-dimensional structural diagram of the circuit breaker contact system according to another embodiment of the present invention.

[0016] Figure 3 This is a structural cross-sectional view of the circuit breaker contact system according to an embodiment of the present invention.

[0017] Label Explanation:

[0018] 1. Base, 2. Base plate, 3. Moving contact part, 4. Static contact part, 5. Partition, 6. Pressure relief gap, 21. Groove. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not 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.

[0021] Please refer to the appendix. Figure 1 To be continued Figure 3 An embodiment of this utility model provides a circuit breaker contact system, including a base 1 and a base plate 2 that cooperate with each other. The base 1 and the base plate 2 are respectively provided with a moving contact part 3 and a stationary contact part 4 that are respectively provided with each other. The moving contact part 3 is provided with a partition 5 to prevent the electric arc generated by the circuit breaker tripping from moving downward from the breaking gap between the moving contact part 3 and the stationary contact part 4 in the direction away from the arc extinguishing chamber of the circuit breaker. The base plate 2 is provided with a relief groove 21 corresponding to the partition 5 so that the moving contact part 3 and the stationary contact part 4 can be closed normally, and a pressure relief gap 6 is formed between the partition 5 and the relief groove 21. Understandably, in this embodiment, by setting a partition 5 on the moving contact part 3, during the separation process of the moving contact part 3 and the stationary contact part 4, the partition 5 blocks the gap between them, avoiding the formation of a large gap between them. The gas pressure generated by the arc combustion cannot move downwards, but can only move upwards and be ejected from the arc-extinguishing chamber. The arc, driven by the strong airflow, also moves upwards and enters the corresponding arc-extinguishing chamber, where it is divided by the grid, thereby extinguishing the arc. At the same time, by opening a relief groove 21 on the base plate 2, the moving contact part 3 and the stationary contact part 4 can close normally without being restricted by the externally extending partition 5. Furthermore, a pressure relief gap 6 is formed between the partition 5 and the relief groove 21. This effectively improves the problem that the high gas pressure inside the chamber during arc combustion caused by the partition 5 can lead to the arc being ejected from the arc-extinguishing chamber too quickly, easily causing an external short circuit and making the test (high current short circuit test) fail.

[0022] Please refer to the appendix. Figure 1 To be continued Figure 3In one preferred embodiment, the minimum gap between the inner wall of the clearance groove 21 and the partition 5 is 0.6mm to 1mm. Further, the minimum gap between the inner wall of the clearance groove 21 and the partition 5 is preferably 0.8mm. It is understood that in this embodiment, by reasonably configuring the minimum gap between the inner wall of the clearance groove 21 and the partition 5 to create a suitable pressure relief gap 6, the internal gas pressure can be better controlled at around 5.5 atmospheres when the contact system breaks up and generates an arc. This ensures that the high-pressure gas inside the cavity can both drive the arc upwards into the corresponding arc-extinguishing chamber and prevent the arc from moving too fast and instantly ejecting from the arc-extinguishing chamber, thus avoiding the risk of an external short circuit.

[0023] Please refer to the appendix. Figure 1 To be continued Figure 3 In one preferred embodiment, the partition 5 is made of PA66-GF25 material. In this embodiment, the PA66-GF25 partition releases nitrogen and trace amounts of hydrogen under the high temperature generated by the electric arc. The inert nitrogen gas has a cooling effect on the electric arc, while the hydrogen can burn and consume the oxygen inside the cavity, reducing the combustion conditions of the electric arc and thus facilitating arc extinguishing. However, those skilled in the art should understand that in other embodiments, the partition 5 may also be made of nylon material with the same or similar properties as PA66-GF25, and is not limited to the specific implementation disclosed in this embodiment.

[0024] Please refer to the appendix. Figure 1 To be continued Figure 3 In one preferred embodiment, the extension length of the partition 5 is configured such that the end of the partition 5 remains within the clearance groove 21 during the continuous burning time of the arc generated during the circuit breaker tripping operation. Preferably, the extension length of the partition 5 is configured such that the end of the partition 5 remains within the clearance groove 21 for 10 ms during the circuit breaker tripping operation.

[0025] Please refer to the appendix. Figure 1 To be continued Figure 3 An embodiment of this utility model also provides a circuit breaker, including any of the circuit breaker contact systems described above.

[0026] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model. Therefore, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

Claims

1. A circuit breaker contact system, characterized in that: The circuit includes a base (1) and a base plate (2) that cooperate with each other. The base (1) and the base plate (2) are respectively provided with a moving contact part (3) and a stationary contact part (4) that are respectively provided with each other. The moving contact part (3) is provided with a partition plate (5) to prevent the electric arc generated by the circuit breaker from moving downward from the breaking gap between the moving contact part (3) and the stationary contact part (4) in the direction away from the arc extinguishing chamber of the circuit breaker. The base plate (2) is provided with a relief groove (21) corresponding to the partition plate (5) so that the moving contact part (3) and the stationary contact part (4) can close normally. A pressure relief gap (6) is formed between the partition plate (5) and the relief groove (21).

2. The circuit breaker contact system according to claim 1, characterized in that: The minimum gap between the inner wall of the clearance groove (21) and the partition (5) is 0.6mm to 1mm.

3. The circuit breaker contact system according to claim 2, characterized in that: The minimum gap between the inner wall of the clearance groove (21) and the partition (5) is 0.8 mm.

4. The circuit breaker contact system according to claim 1, characterized in that: The partition (5) is made of PA66-GF25 material.

5. The circuit breaker contact system according to any one of claims 1 to 4, characterized in that: The extension length of the baffle (5) is configured such that the end of the baffle (5) remains within the clearance groove (21) during the continuous burning time of the arc generated when the circuit is opened.

6. The circuit breaker contact system according to claim 5, characterized in that: The extension length of the partition (5) is configured such that the end of the partition (5) remains within the clearance groove (21) for 10 ms during the circuit breaker tripping operation.

7. A circuit breaker, characterized in that: Includes the circuit breaker contact system as described in any one of claims 1 to 6.

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