Arc extinguishing device of circuit breaker and circuit breaker

Abstract

The utility model belongs to the field of switches, and particularly relates to an arc extinguishing device of a circuit breaker and the circuit breaker, the arc extinguishing device comprises a plurality of arc extinguishing grid sheets, flash barriers and gas generating plates, the gas generating plates are arranged close to the gas inlet ends of the arc extinguishing grid sheets and form a certain distance with the arc extinguishing grid sheets, and each gas generating plate is provided with a near end close to the arc extinguishing grid sheets and a far end far away from the arc extinguishing grid sheets; first acting surfaces are formed on the gas production plates close to the near ends, and the distance between the first acting surfaces of the two gas production plates is gradually increased in the direction from the far ends to the near ends. When electric arcs or air flows reach the back of the grid pieces and are subjected to counteraction to blow back, the inclined first acting surfaces can greatly weaken burning loss of high-temperature and high-pressure air flows and high-temperature electric arcs to the gas generation plate, so that burnt plastics cannot occur, and even if a little burning occurs, due to the fact that the inclined first acting surfaces can form a gap similar to a splayed shape, the gas generation plate can be prevented from being burnt. Molten plastic does not clamp the moving contact, and closing cannot be carried out.

Description

Technical Field

[0001] The utility model belongs to the field of switches, and in particular relates to an arc extinguishing device of a circuit breaker and the circuit breaker. Background Art

[0002] Circuit breakers are crucial equipment in low-voltage power distribution systems. As power projects continue to demand more power sources and transmission and distribution equipment, the performance requirements for circuit protection switches are also increasing. Miniaturization, high performance, modularization, and high reliability are currently the primary development directions for molded case circuit breakers. The arc extinguishing mechanism is also a crucial component of molded case circuit breakers, and its effectiveness is directly related to the circuit breaker's electrical life and interrupting capacity. Existing circuit breakers typically incorporate an arc striker and an arc extinguishing chamber within the insulating housing. The arc striker guides the generated arc into the arc extinguishing chamber, which contains arc extinguishing grids, thereby completing the arc extinguishing process.

[0003] Incorporating gas-generating components into arc-extinguishing devices is a common method for improving arc extinguishing performance. These components are typically made of insulating gas-generating materials such as nylon, melamine, and POM. When the arc burns the component, it produces a large amount of gas. This gas propels the arc quickly into the arc-extinguishing grid, achieving the desired effect of gas-blowing. The component also features a narrow slit, which helps improve arc extinguishing performance. Such components require both gas-generating performance and resistance to carbonization, but this, in turn, makes them difficult to achieve high-temperature resistance. Currently, high-temperature-resistant materials struggle to achieve both good gas-generating performance and resistance to carbonization, making it difficult to achieve both. Consequently, current gas-generating components present the following challenges: When the arc or airflow reaches the back of the grid and is blown back by the reaction force, the high-temperature, high-pressure airflow and high-temperature arc damage the component, easily causing melted plastic to form. This can then cause the melted plastic to jam the moving contact, preventing smooth closing. This problem is particularly prevalent in high-voltage DC circuit breakers. Utility Model Content

[0004] The purpose of the utility model is to overcome the shortcomings and deficiencies of the prior art and to provide an arc extinguishing device for a circuit breaker and a circuit breaker.

[0005] The technical solution adopted by the present utility model is as follows: an arc extinguishing device for a circuit breaker, comprising a plurality of arc extinguishing grids and an arc shunt plate, wherein the arc extinguishing grid is arranged between two arc shunt plates, the arc extinguishing grid having an air inlet end and an air outlet end, and a gas generating plate fixed to the inner side of the arc shunt plate, the gas generating plate being arranged near the air inlet end of the arc extinguishing grid and forming a certain distance from the arc extinguishing grid, and having a proximal end close to the arc extinguishing grid and a distal end away from the arc extinguishing grid;

[0006] The gas production plate is formed with a first active surface near the proximal end, and the distance between the first active surfaces of the two gas production plates gradually increases from the distal end to the proximal end.

[0007] The gas production plate forms a second active surface on the side of the first active surface close to the distal end. The distance between the second active surfaces of the two gas production plates gradually increases from the distal end to the proximal end. An active chamber for accommodating the moving contact of the moving contact is formed between the two second active surfaces.

[0008] The slope of the first active surface is greater than the slope of the second active surface.

[0009] The first action surface and the second action surface are both planes, and there is a rounded arc surface transition between the first action surface and the second action surface. The first action surface transitions to the proximal end surface of the gas production plate with a rounded arc surface.

[0010] The arc-extinguishing grids are distributed at intervals in an arc shape, and the proximal end surface of the gas production plate is an arc surface with a distribution trend similar to that of the arc-extinguishing grids.

[0011] The proximal end surface of the gas production plate has an inclined section, a horizontal section and a vertical section connected in sequence, and a plurality of arc extinguishing grids have an inclined section arc extinguishing grid group, a vertical section arc extinguishing grid group and a horizontal section arc extinguishing grid group with the same distribution trends as the inclined section, the vertical section and the horizontal section respectively.

[0012] The gas production plate is formed with a static contact mounting groove on one side of the inclined section and an inclined third action surface is formed near the static contact mounting groove.

[0013] A circuit breaker provided with the arc extinguishing device as described above comprises a moving contact rotatably extending between two gas-producing plates and a stationary contact installed between the two gas-producing plates.

[0014] It also includes an arc extinguishing device, which is arranged close to the gas outlet end of the arc extinguishing grid. The arc extinguishing grid is arranged obliquely and its gas outlet end is inclined toward the arc extinguishing device.

[0015] An arc striking angle is formed on a side of the end of the moving contact away from the moving contact point, and the arc striking angle extends to the first action surface area.

[0016] The beneficial effects of the present invention are as follows: the present invention arranges a gas-producing plate on the air inlet side of the arc-extinguishing structure composed of a plurality of arc-extinguishing grids, and forms an inclined first acting surface on the side of the gas-producing plate close to the arc-extinguishing grid. When the electric arc or airflow reaches the rear of the grid and is blown back by the reaction, the inclined first acting surface will greatly weaken the burning of the gas-producing parts by the high-temperature and high-pressure airflow and the high-temperature electric arc, so that the plastic will not be melted. Even under high pressure and high temperature, the gas-producing plate will inevitably be slightly melted. Since the inclined first acting surface will form an eight-shaped notch, the melted plastic will not get stuck on the moving contact and cannot be closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0018] Figure 1 An exploded view of the arc extinguishing device provided in Example 1;

[0019] Figure 2 A cross-sectional view of the arc extinguishing device provided in Example 1 at one angle;

[0020] Figure 3 A schematic structural diagram of the gas production plate provided in Example 1;

[0021] Figure 4 for Figure 2 Cross-sectional view in the AA direction;

[0022] Figure 5 A cross-sectional view of two mating structures of gas production plates provided in Example 1;

[0023] Figure 6 This is a schematic diagram of the partial structure of the circuit breaker of Example 1;

[0024] Figure 7 A schematic structural diagram of the gas production plate provided in Example 2;

[0025] Figure 8 This is a schematic diagram of the partial structure of the circuit breaker of Example 2;

[0026] Figure 9 A schematic structural diagram of the gas production plate provided in Example 3;

[0027] Figure 10 This is a schematic diagram of the partial structure of the circuit breaker of Example 3;

[0028] In the figure, arc extinguishing grid-1, inclined section arc extinguishing grid group-101, vertical section arc extinguishing grid group-102, horizontal section arc extinguishing grid group-103, arc isolation plate-2, gas production plate-3, proximal end-301, distal end-302, first active surface-303, second active surface-304, inclined section-305, horizontal section-306, vertical section-307, third active surface-308, moving contact-4, arc striking angle-401, static contact-5, arc flashover elimination device-6. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in further detail below with reference to the accompanying drawings.

[0030] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two non-identical entities or non-identical parameters with the same name. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. Subsequent embodiments will not explain this one by one.

[0031] The directional and positional terms used in this invention, such as up, down, front, back, left, right, inside, outside, top, bottom, and side, are merely references to the directions or positions in the accompanying drawings. Therefore, the directional and positional terms used are intended to illustrate and facilitate understanding of this invention and are not intended to limit the scope of protection of this invention.

[0032] Example 1:

[0033] An arc extinguishing device for a circuit breaker, such as Figure 1 As shown, it includes several arc extinguishing grids 1 and arc isolation plates 2. The arc extinguishing grid 1 is arranged between two arc isolation plates 2. The arc extinguishing grid 1 has an air inlet end and an air outlet end. A gas production plate 3 is fixed inside the arc isolation plate 2. Figure 2 As shown, the gas production plate 3 is arranged close to the gas inlet end of the arc quenching grid 1 and forms a certain distance from the arc quenching grid 1, and has a proximal end 301 close to the arc quenching grid 1 and a distal end 302 away from the arc quenching grid 1; Figure 3 、 Figure 4 As shown, the gas-producing plate 3 has a first active surface 303 formed near the proximal end 301. The spacing between the first active surfaces 303 of the two gas-producing plates 3 gradually increases from the distal end 302 toward the proximal end 301. The inclined first active surface 303 creates a force that pushes the arc or airflow, facilitating arc extinguishing. Furthermore, when the arc or airflow reaches the rear of the grid and encounters a reactionary blowback, the inclined first active surface significantly reduces the damage to the gas-producing components caused by the high-temperature, high-pressure airflow and arc, preventing the plastic from melting. Even under high pressure and temperature, some melting of the gas-producing plate is inevitable. However, the inclined first active surface creates a figure-eight-shaped gap, preventing the melted plastic from blocking the moving contact and preventing closing.

[0034] Further, such as Figure 3 、 Figure 4 As shown, the gas production plate 3 has a second active surface 304 formed on the side of the first active surface 303 near the distal end 302. The spacing between the second active surfaces 304 of the two gas production plates 3 gradually increases from the distal end 302 to the proximal end 301. A movable chamber accommodating the moving contact of the movable contact 4 is formed between the two second active surfaces 304. The inclined second active surface 304 corresponds to the active area of the moving contact. The arc generated at the moment of disconnection is propelled by the inclined second active surface 304, which blows it more quickly toward the grid.

[0035] Furthermore, the slope of the first action surface 303 is greater than the slope of the second action surface 304 .

[0036] Furthermore, the first action surface 303 and the second action surface 304 are both planes, and a rounded arc surface transition is formed between the first action surface 303 and the second action surface 304 . The first action surface 303 transitions to the end surface of the proximal end 301 of the gas production plate 3 with a rounded arc surface.

[0037] Furthermore, the arc-extinguishing grids 1 are distributed at intervals in an arc shape, and the end surface of the proximal end 301 of the gas production plate 3 is an arc surface similar to the distribution trend of the arc-extinguishing grids 1. In this way, more arc-extinguishing grids 1 can be arranged.

[0038] A circuit breaker, such as Figure 6 As shown, it includes a moving contact 4, a static contact 5 and the above-mentioned arc extinguishing device. The moving contact 4 extends between the two gas-producing plates 3, and the static contact 5 is fixed between the two gas-producing plates 3 and is located on one side of the two gas-producing plates 3. The moving contact 4 rotates between the two gas-producing plates 3 and cooperates with the static contact 5. The arc formed during disconnection directly acts on the gas-producing plates 3, causing the gas-producing plates 3 to quickly produce gas to form a gas blowing effect, thereby blowing the arc toward the arc extinguishing grid 1.

[0039] The arc extinguishing device 6 is also included. The arc extinguishing device 6 is positioned near the outlet end of the arc quenching grid 1. The arc quenching grid 1 is tilted, with its outlet end tilted toward the arc extinguishing device 6. This guides the arc toward the arc extinguishing device 6. The arc extinguishing device 6 shown in the figure is disclosed in the applicant's prior patent CN202323241392.4 and will not be described in detail here.

[0040] Furthermore, an arc striking angle is formed on a side of the end of the moving contact 4 away from the moving contact point, and the arc striking angle 401 extends to the first active surface 303 area.

[0041] Example 2:

[0042] The structure of this embodiment is substantially the same as that of embodiment 1, except for the structure of the gas production plate and the layout of the arc extinguishing grid 1. Figure 7 、 Figure 8As shown, the proximal end 301 of the gas production plate 3 has an inclined section 305, a vertical section 306, and a horizontal section 307 connected in sequence. A plurality of arc quenching grids 1 have an inclined section arc quenching grid group 101, an upright section arc quenching grid group 102, and a horizontal section arc quenching grid group 103, which have the same distribution trends as the inclined section 305, the upright section 306, and the horizontal section 307. The arc quenching grids 1 in the inclined section arc quenching grid group 101 are distributed obliquely upward, the arc quenching grids 1 in the upright section arc quenching grid group 102 are distributed vertically or nearly vertically upward, and the arc quenching grids 1 in the horizontal section arc quenching grid group 103 are distributed horizontally or nearly horizontally. A right angle is formed between the upright section arc quenching grid group 102 and the horizontal section arc quenching grid group 103, as shown in FIG. Figure 8 As shown, the arc extinguishing device 6 is arranged at a right angle between the vertical arc extinguishing grid group 102 and the horizontal arc extinguishing grid group 103, which is conducive to the collection and elimination of arcs.

[0043] Example 3:

[0044] The structure of this embodiment is roughly the same as that of embodiment 2. Figure 9 、 Figure 10 Based on the structure of the gas production plate 3 of Example 2, this embodiment forms a static contact mounting groove on one side of the inclined section 305 of the gas production plate 3 and forms an inclined third active surface 308 near the static contact mounting groove.

[0045] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

Claims

1. An arc extinguishing device for a circuit breaker, comprising a plurality of arc extinguishing grids (1) and arc isolation plates (2), wherein the arc extinguishing grid (1) is arranged between two arc isolation plates (2), and the arc extinguishing grid (1) has an air inlet end and an air outlet end, and is characterized in that: A gas production plate (3) is fixed inside the arc isolation plate (2), and the gas production plate (3) is arranged close to the air inlet end of the arc extinguishing grid (1) and forms a certain distance from the arc extinguishing grid (1), and has a proximal end (301) close to the arc extinguishing grid (1) and a distal end (302) far away from the arc extinguishing grid (1); The gas production plate (3) is formed with a first active surface (303) near the proximal end (301), and the distance between the first active surfaces (303) of the two gas production plates (3) gradually increases from the distal end (302) to the proximal end (301).

2. The arc extinguishing device of the circuit breaker according to claim 1, characterized in that: The gas production plate (3) is formed with a second action surface (304) on one side of the first action surface (303) close to the distal end (302), and the spacing between the second action surfaces (304) of the two gas production plates (3) gradually increases from the distal end (302) to the proximal end (301), and an active chamber for accommodating the moving contact of the moving contact (4) for movement is formed between the two second action surfaces (304).

3. The arc extinguishing device of the circuit breaker according to claim 2, characterized in that: The slope of the first active surface (303) is greater than the slope of the second active surface (304).

4. The arc extinguishing device of the circuit breaker according to claim 3, characterized in that: The first action surface (303) and the second action surface (304) are both planes, and a rounded arc surface transition is formed between the first action surface (303) and the second action surface (304), and the first action surface (303) transitions to the rounded arc surface of the proximal end (301) of the gas production plate (3).

5. The arc extinguishing device of the circuit breaker according to claim 1, characterized in that: The plurality of arc-extinguishing grids (1) are distributed at intervals in an arc line, and the end surface of the proximal end (301) of the gas production plate (3) is an arc line surface with a distribution trend similar to that of the plurality of arc-extinguishing grids (1).

6. The arc extinguishing device of the circuit breaker according to claim 1, characterized in that: The proximal end (301) of the gas production plate (3) has an inclined section (305), an upright section (306), and a horizontal section (307) connected in sequence, and the plurality of arc-extinguishing grids (1) have an inclined section arc-extinguishing grid group (101), an upright section arc-extinguishing grid group (102), and a horizontal section arc-extinguishing grid group (103) having the same distribution trends as the inclined section (305), the upright section (306), and the horizontal section (307).

7. The arc extinguishing device of the circuit breaker according to claim 6, characterized in that: The gas production plate (3) is formed with a static contact mounting groove on one side of the inclined section (305) and an inclined third action surface (308) is formed near the static contact mounting groove.

8. A circuit breaker provided with the arc extinguishing device according to any one of claims 1 to 7, characterized in that: It comprises a moving contact (4) that can be rotatably extended between two gas-producing plates (3) and a stationary contact (5) installed between the two gas-producing plates (3).

9. The circuit breaker of the arc extinguishing device according to claim 8, characterized in that: It also includes an arc extinguishing device (6), which is arranged close to the gas outlet end of the arc extinguishing grid (1). The arc extinguishing grid (1) is arranged obliquely and its gas outlet end is inclined toward the arc extinguishing device (6).

10. The circuit breaker of the arc extinguishing device according to claim 8, characterized in that: An arc striking angle (401) is formed on a protrusion on one side of the end of the moving contact (4) away from the moving contact point, and the arc striking angle (401) extends to the first action surface (303) area.

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