Arc extinguishing system of direct-current molded case circuit breaker

Abstract

The utility model discloses an arc extinguishing system of a DC molded case circuit breaker, which comprises an arc extinguishing chamber arranged on a static contact of the circuit breaker and used for performing arc extinguishing on the static contact; and the insulating baffle plate is arranged above the static contact so as to form insulating isolation between the arc extinguish chamber grid plate and the static contact. According to the arc extinguishing system of the DC molded case circuit breaker, through the arrangement of the insulating baffle plate, the isolation between the arc extinguishing chamber and the static contact can be effectively realized, and the risk that the arc extinguishing chamber and the static contact are broken down by the on-off arc can be well avoided.

Description

Technical Field

[0001] The utility model relates to a molded case circuit breaker, and more specifically to an arc extinguishing system of a DC molded case circuit breaker. Background Art

[0002] Currently, the known single-break circuit breakers used in DC high-current and high-voltage circuits are often designed to increase the area, size, and number of arc-extinguishing chamber grids to improve the circuit breaker's energy absorption capacity and arc erosion resistance, thereby achieving normal operation of the circuit breaker under high-current switching conditions. Such a design often easily causes the gap between the arc-extinguishing chamber grid and the static contact in the arc-extinguishing system to be too small, resulting in insufficient electrical clearance. In this case, there is a great risk that the switching arc will break through the arc-extinguishing chamber and the static contact. Utility Model Content

[0003] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a DC molded case circuit breaker arc extinguishing system that solves the risk of internal breakdown of the circuit breaker under high breaking conditions faced by traditional circuit breakers.

[0004] To achieve the above purpose, the utility model provides the following technical solution: a DC molded case circuit breaker arc extinguishing system, characterized in that it includes:

[0005] The arc extinguishing chamber is arranged on the static contact of the circuit breaker to extinguish the arc of the static contact;

[0006] The insulating baffle is installed above the stationary contact to form an insulating isolation between the arc extinguishing chamber grid and the stationary contact.

[0007] As a further improvement of the utility model, the insulating baffle includes a side baffle and a bottom baffle, the bottom baffle is installed above the static contact, and the side baffle is installed at the tail end of the arc extinguishing chamber to wrap the tail end of the arc extinguishing chamber.

[0008] As a further improvement of the present invention, a convex rib is provided on the lower side of the bottom partition, and the convex rib is in contact with the static contact to raise the bottom partition and form a gap between the bottom partition and the static contact.

[0009] As a further improvement of the utility model, a connecting plate is provided between the side baffle and the bottom partition, and the two sides of the connecting plate are respectively transitioned to the side baffle and the bottom partition in an arc shape to connect the side baffle and the bottom partition, and an installation groove for installation on the circuit breaker housing is formed between the side edge of the connecting plate and the side edge of the side baffle, and a labyrinth groove structure is formed between the installation groove and the circuit breaker housing.

[0010] As a further improvement of the utility model, a convex strip is provided on one side surface of the connecting plate facing away from the bottom partition plate, and the convex strip is in contact with the static contact to form a gap between the connecting plate and the static contact.

[0011] As a further improvement of the utility model, a plurality of exhaust holes are distributed on the side baffle.

[0012] As a further improvement of the present invention, the exhaust hole is arranged in a circular shape.

[0013] As a further improvement of the utility model, the arc extinguishing chamber includes a side plate and a plurality of arc extinguishing grids, the side edges of the plurality of arc extinguishing grids are fixed to the side faces of the side plates, and are arranged at intervals with each other to form an arc extinguishing grid group, and the tail edge of the side plate is in contact with the side baffle plate to form a structure that wraps the tail end of the arc extinguishing grid group in combination with the side baffle plate.

[0014] As a further improvement of the utility model, a first notch is provided on one side of the trailing edge of a plurality of arc-extinguishing grid pieces.

[0015] As a further improvement of the present invention, the tail edges of the plurality of arc-extinguishing grids located in the middle of the tail end of the arc-extinguishing grid group are all provided with second notches, so that a depression is formed in the middle of the tail end of the arc-extinguishing grid group.

[0016] Beneficial effects of the utility model:

[0017] By designing and arranging an insulating baffle structure between the arc extinguishing chamber and the static contact, the breakdown risk caused by too small electrical gap between the two is avoided;

[0018] An insulating baffle structure is designed and arranged between the arc extinguishing chamber and the static contact. Through holes are distributed on the baffle structure for exhaust under high current switching conditions. The distributed design of the through holes is conducive to the arc at the tail of the arc extinguishing chamber to be discharged with the airflow, avoiding the risk of breakdown short circuit caused by concentrated discharge of arc due to excessively large exhaust holes;

[0019] The arc extinguishing chamber designed by the utility model for high current switching increases the creepage distance of the arc at the rear of the arc extinguishing chamber through structural adjustment, thereby avoiding the risk of short circuit breakdown at the tail of the arc extinguishing chamber under high current switching conditions;

[0020] The arc extinguishing chamber designed by the utility model for coping with high current switching can realize smooth airflow at the tail of the arc extinguishing chamber under high current switching conditions through the structural design of each layer of arc extinguishing grid, and the generated high-temperature and high-pressure airflow can be discharged from the inside of the circuit breaker cavity in time, avoiding the failure of the arc extinguishing chamber caused by the arc energy being concentrated in the arc extinguishing chamber due to the unsmooth exhaust. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The overall structure diagram of a DC molded case circuit breaker using the arc extinguishing system of the utility model;

[0022] Figure 2 for Figure 1The overall structure diagram of the middle insulating baffle;

[0023] Figure 3 for Figure 1 The structure diagram of the maze tank in the middle B part;

[0024] Figure 4 A cross-sectional view of a DC molded case circuit breaker to which the arc extinguishing system of the utility model is applied;

[0025] Figure 5 for Figure 4 Enlarged view of part A in the middle;

[0026] Figure 6 This is the overall structural diagram of the arc extinguishing chamber. DETAILED DESCRIPTION

[0027] The utility model will be further described below in conjunction with the embodiments given in the accompanying drawings. The tail end and tail edge mentioned in this embodiment are based on the static contact terminal, that is, one side and one end facing the static contact terminal are called the tail edge and tail end.

[0028] Reference Figures 1 to 6 As shown, a DC molded case circuit breaker arc extinguishing system of this embodiment is characterized by comprising:

[0029] The arc extinguishing chamber 1 is arranged on the static contact of the circuit breaker to extinguish the arc of the static contact;

[0030] The insulating baffle 2 is installed above the static contact to form an insulating isolation between the arc extinguishing chamber grid and the static contact. When using the arc extinguishing system of this embodiment, it is only necessary to install the arc extinguishing chamber 1 and the insulating baffle 2 into the housing of the molded case circuit breaker. The static contact can be accommodated in the arc extinguishing chamber 1 to achieve arc extinguishing operation during the on-off process. In addition, the setting of the insulating baffle 2 in this embodiment can utilize the function of the insulating baffle 2 to achieve isolation between the arc extinguishing chamber 1 and the static contact. Compared with the method in the prior art, this avoids the risk of breakdown between the two due to too small an electrical gap.

[0031] As a specific implementation of the improvement, the insulating baffle 2 includes a side baffle 21 and a bottom partition 22, the bottom partition 22 is installed above the static contact, and the side baffle 21 is installed at the tail end of the arc extinguishing chamber 1 to wrap the tail end of the arc extinguishing chamber 1. Through the combination of the side baffle 21 and the bottom partition 22, the static contact and the arc extinguishing chamber 1 can be isolated by using the bottom partition 22. The side baffle 21 constitutes a structure that wraps both sides of the tail end of the arc extinguishing chamber 1, which can further increase the isolation performance between the arc extinguishing chamber 1 and the static contact.

[0032] As a specific implementation of the improvement, a convex rib 221 is provided on the lower side of the bottom partition 22, and the convex rib 221 contacts the static contact to raise the bottom partition 22 and form a gap between the static contact. The setting of the convex rib can achieve a smaller contact surface between the bottom partition 22 and the static contact, and a gap is left between the bottom partition 22 and the arc extinguishing chamber 1 and the static contact, so that it has a better isolation effect.

[0033] As an improved specific implementation method, a connecting plate 23 is provided between the side baffle 21 and the bottom partition 22, and the two sides of the connecting plate 23 are respectively transitioned to the side baffle 21 and the bottom partition 22 in an arc shape to connect the side baffle 21 and the bottom partition 22, and a mounting groove 24 for mounting on the circuit breaker housing is formed between the side edge of the connecting plate 23 and the side edge of the side baffle 21, and a labyrinth groove structure is formed between the mounting groove 24 and the circuit breaker housing. By setting the connecting plate 23, the connection between the side baffle 21 and the bottom partition 22 can be achieved, and by setting the mounting groove 24, the matching guide ribs on the circuit breaker housing can be used to achieve the loading guide for the side baffle 21 and the bottom partition 22. After installation, a labyrinth groove structure is formed between the matching guide ribs and the mounting groove 24, so that the side baffle 21 has better insulation protection performance.

[0034] As an improved specific embodiment, a convex strip 231 is provided on the side surface of the connecting plate 23 facing away from the bottom partition plate 22, and the convex strip 231 is in contact with the static contact to form a gap between the connecting plate 23 and the static contact. By setting the convex strip 231, a gap can be effectively left between the connecting plate 23 and the static contact, so that it has a better isolation effect.

[0035] As a specific implementation of the improvement, a plurality of exhaust holes 211 are distributed on the side baffle plate 21. By distributing through holes for exhaust under high current switching conditions on the side baffle plate 21, the distributed design of the through holes is beneficial for the arc at the tail end of the arc extinguishing chamber 1 to be discharged with the dispersed airflow, thereby avoiding the risk of breakdown short circuit caused by concentrated discharge of arc due to excessively large exhaust holes.

[0036] As an improved specific implementation, the exhaust hole 211 is arranged in a circular shape and adopts a circular structure, which can effectively facilitate processing.

[0037] As an improved specific implementation method, the arc extinguishing chamber 1 includes a side plate 11 and a plurality of arc extinguishing grids 12, and the side edges of the plurality of arc extinguishing grids 12 are fixed to the side edges of the side plate 11 to form an arc extinguishing grid group by being arranged at intervals from each other. The tail edge of the side plate 11 contacts the side baffle plate 21 to form a structure that wraps the tail end of the arc extinguishing grid group in combination with the side baffle plate 21. Through the above structure, the arc extinguishing chamber 1 structure can be simply and effectively constructed, and the wrapping structure can be realized by utilizing the effective cooperation between the tail edge of the side plate 11 and the side baffle plate 21.

[0038] As a specific implementation of the improvement, a first notch 3 is provided on one side of the tail edge of a plurality of arc-extinguishing grids 12, and the single-sided notch structure designed on the tail edge of the arc-extinguishing grid 12 is arranged in an inverted manner in sequence. Figure 6 As shown, this design reduces the risk of arc breakdown on both sides of the tail end of the arc extinguishing chamber 1 compared to the traditional arc extinguishing chamber structure. The principle is that the arc creepage distance on both sides of the tail end of the arc extinguishing chamber 1 is increased compared to the traditional notch-free design, thereby reducing the risk of breakdown.

[0039] As a specific implementation of the improvement, the tail edges of the plurality of arc-extinguishing grids 12 in the middle of the tail end of the arc-extinguishing grid group are all provided with a second notch 4, so that the position in the middle of the tail end of the arc-extinguishing grid group forms a depression. By designing the middle notch at the tail end of the arc-extinguishing grid group, compared with the traditional circuit breaker design facing the high-through end condition, the arc-extinguishing chamber tail end gap is too small, resulting in a blocked airflow channel. This design appropriately increases the exhaust channel, which can realize the rapid discharge of arc energy under high-through and breaking conditions. In addition, the first notch 3 and the second notch 4 in this embodiment are preferably arc-shaped.

[0040] To sum up, the arc extinguishing system of the DC molded case circuit breaker of this embodiment adopts a combined structure of an insulating baffle 2 and an arc extinguishing chamber 1. The arc extinguishing chamber 1 can be used to achieve arc extinguishing. In addition, the insulating baffle 2 is used to isolate the arc extinguishing chamber 1 from the static contact, thereby avoiding the risk of breakdown between the two due to too small an electrical gap.

[0041] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A DC molded case circuit breaker arc extinguishing system, characterized in that: include: An arc extinguishing chamber (1) is arranged on the static contact of the circuit breaker to extinguish the arc on the static contact; An insulating baffle (2) is installed above the stationary contact to form an insulating isolation between the arc extinguishing chamber grid and the stationary contact.

2. The DC molded case circuit breaker arc extinguishing system according to claim 1, characterized in that: The insulating baffle (2) comprises a side baffle (21) and a bottom baffle (22), wherein the bottom baffle (22) is installed above the static contact, and the side baffle (21) is installed at the rear end of the arc extinguishing chamber (1) to wrap the rear end of the arc extinguishing chamber (1).

3. The DC molded case circuit breaker arc extinguishing system according to claim 2, characterized in that: The lower side surface of the bottom partition plate (22) is provided with a convex rib (221), and the convex rib (221) is in contact with the static contact to raise the bottom partition plate (22) to form a gap with the static contact.

4. The DC molded case circuit breaker arc extinguishing system according to claim 2 or 3, characterized in that: A connecting plate (23) is provided between the side baffle (21) and the bottom baffle (22); two sides of the connecting plate (23) respectively transition with the side baffle (21) and the bottom baffle (22) in an arc shape so as to connect the side baffle (21) and the bottom baffle (22); a mounting groove (24) for mounting on a circuit breaker housing is formed between the side edge of the connecting plate (23) and the side edge of the side baffle (21); a labyrinth groove structure is formed between the mounting groove (24) and the circuit breaker housing.

5. The DC molded case circuit breaker arc extinguishing system according to claim 4, characterized in that: A convex strip (231) is provided on one side of the connecting plate (23) facing away from the bottom partition plate (22), and the convex strip (231) is in contact with the stationary contact to form a gap between the connecting plate (23) and the stationary contact.

6. The DC molded case circuit breaker arc extinguishing system according to claim 4, characterized in that: A plurality of exhaust holes (211) are distributed on the side baffle (21).

7. The DC molded case circuit breaker arc extinguishing system according to claim 6, characterized in that: The exhaust hole (211) is arranged in a circular shape.

8. The DC molded case circuit breaker arc extinguishing system according to claim 2 or 3, characterized in that: The arc extinguishing chamber (1) comprises a side plate (11) and a plurality of arc extinguishing grids (12); the side edges of the plurality of arc extinguishing grids (12) are fixed to the side edges of the side plate (11) so as to be arranged at intervals to form an arc extinguishing grid group; the rear edge of the side plate (11) is in contact with a side baffle plate (21) so as to be combined with the side baffle plate (21) to form a structure that wraps the rear end of the arc extinguishing grid group.

9. The DC molded case circuit breaker arc extinguishing system according to claim 8, characterized in that: A first notch (3) is provided on one side of the tail edge of a plurality of arc-extinguishing grid pieces (12).

10. The arc extinguishing system for DC molded case circuit breaker according to claim 8, characterized in that: The tail edges of a plurality of arc-extinguishing grids (12) located in the middle of the tail end of the arc-extinguishing grid group are all provided with second notches (4), so that a depression is formed in the middle of the tail end of the arc-extinguishing grid group.

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