A molded case circuit breaker beneficial to arc extinction

Abstract

This utility model discloses a molded case circuit breaker that facilitates arc extinguishing, including a housing, a contact mechanism, and an arc extinguishing mechanism. The arc extinguishing mechanism includes two arc-isolating plates, forming an arc extinguishing space between them. The arc extinguishing space includes an arc initiation port and an exhaust channel. Gas-generating plates are provided within the arc extinguishing space, and multiple spaced arc-extinguishing grids are formed within the arc extinguishing space. The space between the multiple arc-extinguishing grids is connected to the exhaust channel, and an arc outlet is formed on the exhaust channel. An arc exhaust channel is provided on the housing, so that the arc entering the arc extinguishing space is cut into short arcs by the multiple arc-extinguishing grids, and the arc is quickly extinguished under the synergistic effect of the space and the gas-generating plates. The arc that enters the exhaust channel during the arc extinguishing process is discharged to the outside of the housing through the arc outlet and the arc exhaust channel, thereby improving the arc extinguishing effect and the performance of the molded case circuit breaker.

Description

Technical Field

[0001] This utility model belongs to the field of circuit breaker technology, specifically relating to a molded case circuit breaker that facilitates arc extinguishing. Background Technology

[0002] Molded case circuit breakers are widely used products, frequently applied in low-voltage power distribution systems. They not only provide power to the distribution lines but also serve the dual purpose of protecting and controlling the circuits, playing a crucial role in the safety, reliability, and practicality of the entire power distribution system.

[0003] To ensure reliable operation of equipment or circuits within a safe range, most molded case circuit breakers on the market are equipped with an arc-extinguishing mechanism. During the circuit breaker's opening phase, the arc generated between the moving and stationary contacts is absorbed and extinguished, preventing the arc from burning the contacts. However, some existing molded case circuit breakers have unreasonable structural designs, which prevent the gas arc from being quickly discharged during the arc-extinguishing process. This causes the high-temperature gas arc to accumulate inside the casing, resulting in the molded case circuit breaker's inability to quickly extinguish the arc during use, thus affecting its breaking capacity. Utility Model Content

[0004] Therefore, the purpose of this utility model is to provide a molded case circuit breaker that facilitates arc extinguishing.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This utility model provides a molded case circuit breaker that facilitates arc extinguishing, including a housing, a contact mechanism disposed within the housing, an arc extinguishing mechanism distributed on one side of the contact mechanism, and inlet and outlet positions respectively disposed on both sides of the housing; the contact mechanism includes a moving contact and a stationary contact, the arc extinguishing mechanism includes two arc-isolating plates arranged opposite each other and spaced apart, forming an arc extinguishing space between the two arc-isolating plates, the front end of the arc extinguishing space has an arc-initiating port for the moving and stationary contacts to extend into, and the rear end has an exhaust channel; gas-generating plates are respectively disposed on both sides of the arc-initiating port, a plurality of arc-extinguishing grids are formed in the arc extinguishing space, and the space between adjacent arc-extinguishing grids connects the arc-initiating port and the exhaust channel, the exhaust channel has an arc outlet on the side away from the arc-extinguishing grids, and the housing is provided with an arc exhaust channel connecting the arc outlet to the outside.

[0007] Preferably, the housing includes a base and a cover covering the upper part of the base, and the gas arc exhaust channel is opened at the side end of the cover.

[0008] Preferably, the stationary contact includes a stationary contact plate and stationary contact points. The stationary contact points are distributed at one end of the stationary contact plate, extending into the arc inlet. The other end of the stationary contact plate extends to the wire outlet as a terminal. The contact mechanism also includes an insulating cover, which is mounted on the stationary contact plate. An upwardly extending baffle plate is integrally provided on the insulating cover, and the baffle plate is located behind the exhaust channel.

[0009] Preferably, an operation clearance area for wiring operations is provided above the wiring terminals corresponding to each pole on the shell cover, and the gas arc exhaust channel is provided on both sides of the operation clearance area; a pole spacer arc plate slot is provided on the side end face of the shell between two adjacent poles in the vertical direction, and there is a gap between the upper edge of the outer port of the gas arc exhaust channel provided near the pole spacer arc plate slot and the upper edge of the corresponding side end of the shell cover, and the gap is not less than 8mm.

[0010] Preferably, the insulating cover includes a horizontal cover portion that covers the stationary contact plate in a transverse manner and a vertical cover portion that covers the stationary contact plate in a longitudinal manner. The lower end of the vertical cover portion is integrated with the horizontal cover portion, and the upper end is connected to the air baffle plate. A gap is provided between the vertical cover portion and the arc extinguishing grid plate, and the distance between the air baffle plate and the arc extinguishing grid plate is greater than the distance between the vertical cover portion and the arc extinguishing grid plate.

[0011] Preferably, an arc-extinguishing plate is provided at the arc outlet, and the arc-extinguishing plate has multiple exhaust holes.

[0012] Preferably, the distance between the air baffle plate and the arc-extinguishing grid plate, and the distance between the longitudinal cover and the arc-extinguishing grid plate are both greater than 3mm.

[0013] The positive effects of this utility model are as follows: By optimizing the structure of the molded case circuit breaker, specifically by setting an arc-extinguishing mechanism including arc-isolating plates and an arc-extinguishing space between the two arc-isolating plates, the front end of the arc-extinguishing space forms an arc-starting port, and the rear end of the arc-extinguishing space is provided with an exhaust channel for venting the gas arc. Gas-generating plates are correspondingly arranged on both sides of the arc-starting port. Simultaneously, the arc-extinguishing space is provided with multiple spaced arc-extinguishing grids, and the space between adjacent arc-extinguishing grids connects the arc-starting port and the exhaust channel. An arc outlet is formed on the side of the exhaust channel furthest from the arc-extinguishing grids. The housing portion… An arc discharge channel is provided at the corresponding arc outlet position. Thus, when the molded case circuit breaker is in the opening and closing stage, the electric arc formed on the contact mechanism enters the arc extinguishing space. The arc is cut into short arcs by multiple arc extinguishing grids. At the same time, under the synergistic effect of the space between the multiple arc extinguishing grids and the gas generating plates, the generated arc can be quickly discharged through the exhaust channel. After entering the exhaust channel, the arc can be quickly discharged to the outside of the casing through the arc outlet and the arc discharge channel, thereby ensuring the arc extinguishing efficiency and reliability of the molded case circuit breaker in this utility model. Attached Figure Description

[0014] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art are briefly introduced below. Similar elements or parts in the drawings are generally identified by similar reference numerals. The elements or parts in the drawings are not necessarily drawn to scale.

[0015] Figure 1 This is a three-dimensional schematic diagram of the molded case circuit breaker in this utility model;

[0016] Figure 2 for Figure 1 Enlarged schematic diagram;

[0017] Figure 3 This is a front view schematic diagram of the molded case circuit breaker in this utility model;

[0018] Figure 4 for Figure 3 Enlarged schematic diagram;

[0019] Figure 5 This is a top view of the molded case circuit breaker in this utility model;

[0020] Figure 6 for Figure 5 AA sectional view;

[0021] Figure 7 for Figure 6 Enlarged schematic diagram;

[0022] Figure 8 This is a schematic diagram of the structure of the stationary contact, insulating cover and arc-extinguishing plate installed on the arc-extinguishing mechanism in this utility model.

[0023] The reference numerals in the figure are as follows: 1. Housing; 11. Housing cover; 111. Operating clearance area; 112. Polar spacer slot; 113. Gas arc exhaust channel; 12. Base; 2. Arc extinguishing plate; 21. Exhaust hole; 3. Contact mechanism; 31. Moving contact; 32. Stationary contact; 321. Stationary contact piece; 322. Stationary contact point; 33. Insulating cover; 331. Longitudinal cover; 332. Horizontal cover; 4. Air baffle plate; 5. Arc extinguishing mechanism; 50. Arc initiation port; 51. Gas generating plate; 52. Arc extinguishing grid plate; 521. Spacer; 53. Arc isolation plate; 54. Gas arc outlet; 10. Outgoing line position; 101. Wiring busbar; 20. Incoming line position; 30. Arc initiation port; 40. Exhaust channel. Detailed Implementation

[0024] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0025] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this utility model pertains.

[0026] like Figure 1-8 As shown, the molded case circuit breaker of this utility model embodiment includes a housing 1, a contact mechanism 3 disposed within the housing 1, an arc-extinguishing mechanism 5 distributed on one side of the contact mechanism 3, an operating mechanism connected to the circuit breaker handle and used to drive the contact mechanism 3 to perform opening and closing actions, and an inlet position 20 and an outlet position 10 respectively disposed on both sides of the housing 1; the inlet position 20 and the outlet position 10 are used to connect external lines (such as connecting to a power busbar); the contact mechanism 3 includes a moving contact 31 and a stationary contact 32, and the arc-extinguishing mechanism 5 includes two arc-blocking plates 53 arranged opposite to each other and spaced apart, with the two arc-blocking plates 53 forming a gap. An arc-extinguishing space is formed, with an arc-initiating port 50 at its front end for the insertion of moving and stationary contacts, and an exhaust channel 40 at its rear end. Gas-generating plates 51 are respectively arranged on both sides of the arc-initiating port 50. Multiple spaced arc-extinguishing grids 52 are formed within the arc-extinguishing space, and the space 521 between adjacent arc-extinguishing grids 52 connects the arc-initiating port 50 and the exhaust channel 40. An arc outlet 54 is formed on the side of the exhaust channel 40 away from the arc-extinguishing grids 52. An arc exhaust channel 113 connecting the arc outlet 54 to the outside is provided on the housing 1. The gas-generating plates 51 are made of materials that can generate gas when heated, such as melamine; the generation of gas helps to accelerate the transfer speed of the arc, thereby improving the arc-extinguishing effect.

[0027] The arc-extinguishing mechanism 5 includes an arc-blocking plate 53 and an arc-extinguishing space located between the two arc-blocking plates 53. The front end of the arc-extinguishing space forms an arc-initiating port 50, and the rear end of the arc-extinguishing space is provided with an exhaust channel 40 for venting the gas arc. Gas-generating plates 51 are correspondingly arranged on both sides of the arc-initiating port 50. Simultaneously, the arc-extinguishing space is provided with multiple spaced arc-extinguishing grids 52. The space 521 between adjacent arc-extinguishing grids 52 connects the arc-initiating port 52 to the exhaust channel 40. A gas arc outlet 54 is formed on the side of the exhaust channel 40 that is furthest from the arc-extinguishing grids 52. The housing 1 portion has a corresponding gas arc outlet 54... An arc discharge channel 113 is provided at the location, so that when the molded case circuit breaker is in the opening and closing stage, the electric arc formed on the contact mechanism 3 enters the arc extinguishing space. The arc is cut into short arcs by multiple arc extinguishing grids 52. At the same time, with the synergistic effect of the interval space 521 and the gas generating plate 51, the generated arc can be quickly discharged through the exhaust channel 40. After entering the exhaust channel 40, the arc can be quickly discharged to the outside of the housing 1 through the arc outlet 54 and the arc discharge channel 113, thereby ensuring the arc extinguishing efficiency and reliability of the molded case circuit breaker in this utility model.

[0028] like Figure 1-4As shown, the housing 1 includes a base 12 and a cover 11 covering the upper part of the base 12. The gas arc exhaust channel 113 is designed to be opened at the side end of the cover 11. The gas arc moves from the base 12 towards the cover 11 and is discharged. This can avoid the high temperature gas arc from having an adverse effect on the wiring part at the base 12.

[0029] like Figure 6-8 As shown, the stationary contact 32 includes a stationary contact piece 321 and a stationary contact point 322. The stationary contact point 322 is distributed at one end of the stationary contact piece 321 and extends into the arc inlet 50. The other end of the stationary contact piece 321 extends to the outlet position 10 as a terminal for connecting external lines. The contact mechanism 3 also includes an insulating cover 33, which covers the stationary contact piece 321. An upwardly extending air baffle 4 is integrally provided on the insulating cover 33. The air baffle 4 is located behind the exhaust channel 40 and can block the airflow.

[0030] like Figure 1-5 As shown, an operation clearance area 111 for wiring operations is provided above the wiring terminals corresponding to each pole on the cover 11. When wiring, the operating tool is inserted from the operation clearance area 111 to tighten the wiring screw that is fixedly connected to the external busbar 101. The gas arc exhaust channel 113 is provided on both sides of the operation clearance area 111. On the side end face of the housing 1, a pole spacer arc plate slot 112 is provided between adjacent poles in the vertical direction. The upper edge of the outer port of the gas arc exhaust channel 113 near the pole spacer arc plate slot 112 is spaced from the upper edge of the corresponding side end of the cover 11, and the space is not less than 8mm. This design is mainly based on the following considerations: In practical applications, a pole spacer is usually inserted in the pole spacer arc plate slot 112 to achieve effective isolation between adjacent poles. However, since the arc discharge channel 113 is located on the cover 11, if the distance between the upper edge of the outer port of two adjacent arc discharge channels 113 and the upper edge of the corresponding side end of the cover 11 is too small, it will lead to insufficient creepage distance and pose a risk of reduced electrical insulation performance. To ensure safety, in this embodiment, the above-mentioned distance is set to not less than 8mm to ensure sufficient creepage distance between phases, thereby significantly enhancing electrical insulation performance. This optimized design effectively improves the overall performance of the molded case circuit breaker.

[0031] like Figure 6-8As shown, the insulating cover 33 includes a horizontal cover portion 332 that covers the stationary contact piece 321 in a transverse manner and a vertical cover portion 331 that covers the stationary contact piece 321 in a longitudinal manner. The lower end of the vertical cover portion 331 is integrated with the horizontal cover portion 332, and the upper end is connected to the air baffle plate 4. There is a gap between the vertical cover portion 331 and the arc extinguishing grid plate 52, and the distance between the air baffle plate 4 and the arc extinguishing grid plate 52 is greater than the distance between the vertical cover portion 331 and the arc extinguishing grid plate 52. This design optimizes the arc flow path, effectively enhances the exhaust efficiency, and avoids the accumulation or retention of arc inside the housing, thereby improving reliability and safety.

[0032] like Figure 3-4 As shown in Figure 6-8, an arc-extinguishing plate 2 is provided at the arc outlet 54. The arc-extinguishing plate 2 has multiple exhaust holes 21. The arc-extinguishing plate 2 can further extinguish the electric arc in the gas arc and improve the arc extinguishing effect. The number of arc-extinguishing plates can be set as needed, such as one, two or three.

[0033] like Figure 6-8 As shown, the distance between the air baffle plate 4 and the arc-extinguishing grid plate 52, and the distance between the longitudinal cover 331 and the arc-extinguishing grid plate 52 are both greater than 3mm; specifically, for example, the distance between the air baffle plate 4 and the arc-extinguishing grid plate 52 is set to be greater than 6mm, and the distance between the longitudinal cover 331 and the arc-extinguishing grid plate 52 is greater than 4mm. This design ensures the effective formation of the exhaust channel 40 in the molded case circuit breaker, which is conducive to the smooth discharge of gas and improves the performance of the molded case circuit breaker.

[0034] For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, these obvious variations or modifications derived from the essential spirit of this invention still fall within the scope of protection of this invention.

Claims

1. A molded case circuit breaker that facilitates arc extinguishing, comprising a housing (1), a contact mechanism (3) disposed within the housing (1), an arc extinguishing mechanism (5) distributed on one side of the contact mechanism (3), and an inlet (20) and an outlet (10) respectively disposed at both ends of the housing; the contact mechanism (3) comprises a moving contact (31) and a stationary contact (32); characterized in that: The arc extinguishing mechanism (5) includes two arc-blocking plates (53) arranged opposite to each other and spaced apart, forming an arc extinguishing space between the two arc-blocking plates (53). The front end of the arc extinguishing space has an arc-initiating port (50) for the moving and stationary contacts to extend into, and the rear end has an exhaust channel (40). Gas-generating plates (51) are respectively arranged on both sides of the arc-initiating port (50). Multiple arc-extinguishing grid plates (52) are formed in the arc extinguishing space, and the space between adjacent arc-extinguishing grid plates (52) (521) connects the arc-initiating port (50) and the exhaust channel (40). An arc outlet (54) is formed on the side of the exhaust channel (40) that is away from the arc-extinguishing grid plate (52). The housing (1) is provided with an arc exhaust channel (113) that connects the arc outlet (54) to the outside.

2. The molded case circuit breaker with arc-extinguishing capability according to claim 1, characterized in that: The housing (1) includes a base (12) and a cover (11) covering the upper part of the base (12), and the gas arc exhaust channel (113) is opened at the side end of the cover (11).

3. The molded case circuit breaker with arc-extinguishing capability according to claim 2, characterized in that: The stationary contact (32) includes a stationary contact piece (321) and a stationary contact point (322). The stationary contact point (322) is distributed at one end of the stationary contact piece (321) and extends into the arc inlet (50). The other end of the stationary contact piece (321) extends to the outlet position (10) as a terminal. The contact mechanism (3) also includes an insulating cover (33). The insulating cover (33) is placed on the stationary contact piece (321). An upwardly extending air baffle (4) is integrally provided on the insulating cover (33). The air baffle (4) is located behind the exhaust channel (40).

4. The molded case circuit breaker with arc-extinguishing capability according to claim 3, characterized in that: The cover (11) has an operation clearance area (111) above the wiring terminal corresponding to each pole, and the gas arc exhaust channel (113) is provided on both sides of the operation clearance area (111); the side end face of the housing (1) has a pole spacer plate slot (112) that runs through the vertical direction between two adjacent poles, and the upper edge of the outer port of the gas arc exhaust channel (113) provided near the pole spacer plate slot (112) has a gap with the upper edge of the corresponding side end of the cover (11), and the gap is not less than 8mm.

5. The molded case circuit breaker with arc-extinguishing capability according to claim 3, characterized in that: The insulating cover (33) includes a horizontal cover (332) that covers the stationary contact plate (321) in a horizontal direction and a vertical cover (331) that covers the stationary contact plate (321) in a vertical direction. The lower end of the vertical cover (331) is integrated with the horizontal cover (332), and the upper end is connected to the air baffle plate (4). There is a gap between the vertical cover (331) and the arc extinguishing grid plate (52), and the distance between the air baffle plate (4) and the arc extinguishing grid plate (52) is greater than the distance between the vertical cover (331) and the arc extinguishing grid plate (52).

6. The molded case circuit breaker with arc-extinguishing capability according to claim 1, characterized in that: An arc-extinguishing plate (2) is provided at the arc outlet (54), and multiple exhaust holes (21) are opened on the arc-extinguishing plate (2).

7. The molded case circuit breaker with arc-extinguishing capability according to claim 5, characterized in that: The distance between the air baffle plate (4) and the arc extinguishing grid plate (52), and the distance between the longitudinal cover (331) and the arc extinguishing grid plate (52) are both greater than 3 mm.

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