CN117637406A - Circuit breaker and arc extinguishing chamber thereof - Google Patents

Abstract

The invention discloses an arc-extinguishing chamber of a circuit breaker, which comprises a plurality of grid sheets in layered arrangement, wherein the grid sheets are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid sheets are gradually reduced according to the sequence of contact arcs in a group of grid sheets which finally contact arcs generated by the circuit breaker in all groups; the length of the grating sheet is the size from one end edge corresponding to the inlet of the arc extinguishing chamber to the opposite other end edge in the grating sheet; the grid plates comprise more than 2 first grid plates which are arranged one by one; a notch is arranged at the eccentric position of the edge of the end part of the first grid sheet corresponding to the inlet of the arc extinguishing chamber, and the two parts at two sides of the notch are different in area and respectively comprise a large arc inlet end and a small arc inlet end; the large arc inlet ends and the small arc inlet ends of two adjacent first grid sheets are alternately arranged. The arc-extinguishing chamber can reduce the resistance of the arc entering the arc-extinguishing chamber and improve the arc-extinguishing effect. The invention further provides a circuit breaker applying the arc extinguishing chamber.

Description

Circuit breaker and arc extinguishing chamber thereof

Technical Field

The invention relates to the technical field of mechanical industry, in particular to an arc extinguishing chamber of a circuit breaker and the circuit breaker.

Background

Since the dc current has no current zero crossing characteristic compared with the ac current, the dc circuit breaker cannot extinguish the arc by utilizing the characteristic of the current zero crossing, unlike the ac circuit breaker, which can extinguish the arc only by the arc extinguishing chamber. The arc extinguishing chamber is internally provided with a plurality of grid sheets which are arranged in parallel at equal intervals one by one, when the circuit breaker is switched on and off to generate an arc, the arc enters the arc extinguishing chamber, is cut into short arcs by each grid sheet and cooled, so that the voltage of the arc is increased, the resistance of the arc is increased, and when the voltage of the arc is larger than the voltage of a power supply, the arc is extinguished.

The speed of the arc extinguishing chamber for extinguishing the arc is influenced by the resistance of the arc entering the arc extinguishing chamber, gaps are arranged on the edges of the corresponding ends of the grid sheets and the inlet of the arc extinguishing chamber in the existing arc extinguishing chamber in a centered manner, the gaps are bilaterally symmetrical, the adjacent grid sheets cut the arc simultaneously, the resistance is high, the arc is not beneficial to entering the arc extinguishing chamber rapidly, and the arc extinguishing speed is influenced.

In addition, the static contact module in the circuit breaker is located the rear end of explosion chamber, and a large amount of metal particles are produced in a moment to the separation of static contact module, and explosion chamber rear end contact electric arc earlier, causes explosion chamber rear end to easily block up, leads to explosion chamber rear end department a plurality of adjacent bars to establish ties through metal particles, and the electric potential equals, only plays the effect of a bar piece, and the bar piece cutting electric arc section number diminishes, and electric arc voltage becomes low, is unfavorable for the arc extinction.

In summary, how to optimize the structural design of the grid plate and reduce the resistance of the arc entering the arc extinguishing chamber is a problem to be solved by those skilled in the art.

Disclosure of Invention

In view of this, the invention provides an arc extinguishing chamber of a circuit breaker, wherein a notch is arranged at the eccentric position of the edge of the end part of a first grid plate corresponding to the inlet of the arc extinguishing chamber, the partial areas of the two sides of the notch are different, and the large arc inlet end and the small arc inlet end of two adjacent first grid plates are alternately arranged, so that when an arc enters the arc extinguishing chamber, the large arc inlet end and the small arc inlet end of the first grid plates are repeatedly cut for many times at different times. The invention also provides a circuit breaker applying the arc extinguishing chamber, which can reduce resistance, enable the arc to enter the arc extinguishing chamber rapidly and improve the extinguishing speed of the arc.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the arc extinguishing chamber of the circuit breaker comprises a plurality of grid sheets which are arranged in a layered manner, wherein the grid sheets are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid sheets are gradually reduced according to the sequence of contacting the electric arcs in a group of grid sheets which are finally contacted with the electric arcs generated by the circuit breaker in all groups; the length of the grid sheet is the size from one end edge of the grid sheet corresponding to the inlet of the arc extinguishing chamber to the opposite other end edge; the grid plates comprise more than 2 first grid plates which are arranged one by one, gaps are arranged at the eccentric positions of edges of the end parts of the first grid plates, which correspond to the inlets of the arc extinguishing chambers, and the two parts on two sides of the gaps are different in area and are respectively a large arc inlet end and a small arc inlet end; the large arc inlet ends and the small arc inlet ends of two adjacent first grid sheets are alternately arranged.

Preferably, in the arc extinguishing chamber, the grating sheet further includes a second grating sheet, a gap is provided in a central position of an end edge of the second grating sheet corresponding to the inlet of the arc extinguishing chamber, and portions on two sides of the gap are symmetrical to each other.

Preferably, in the arc extinguishing chamber, the grid plates are divided into three groups, and the first, second and third groups of grid plates are sequentially arranged along the sequence of contacting the electric arc; wherein the first grid plates are adopted by the first group of grid plates and the second group of grid plates respectively; the third set of gate sheets employs the second gate sheet.

Preferably, in the arc extinguishing chamber, the gap size between two adjacent grid plates in the group contacting the arc is larger.

Preferably, in the arc extinguishing chamber, the gap size between any two adjacent grid plates in each group of grid plates is the same.

Preferably, in the arc extinguishing chamber, in each group of the grid plates, the gap size between two adjacent grid plates gradually decreases along the sequence of contacting the arc.

Preferably, in the arc extinguishing chamber, ends of the plurality of grid plates corresponding to the inlets of the arc extinguishing chamber are sequentially arranged into an arc shape, and the shape of the arc shape is consistent with the shape of the moving track of the moving contact module in the circuit breaker.

Preferably, in the arc extinguishing chamber, the arc extinguishing chamber comprises a back plate, a left arc isolation side plate fixed on the back plate and a right arc isolation side plate fixed on the back plate; two ends of each grid sheet are respectively fixed on the two arc-isolation side plates, and each grid sheet is respectively perpendicular to the backboard.

Preferably, in the above arc extinguishing chamber, the arc extinguishing chamber further includes an arc striking plate, a left gas production protective cover and a right gas production protective cover; the arc striking plate is fixed at one end, far away from the fixed contact module of the circuit breaker, of the two arc isolating side plates and the backboard; the left gas production protective cover is fixed on the left arc isolation side plate and covers the left sides of all the grid plates; the right gas production protective cover is fixed on the right arc isolation side plate and covers the right sides of all the grid plates.

The circuit breaker comprises a shell, and an arc extinguishing chamber, a moving contact module and a fixed contact module which are respectively arranged in the shell, wherein the arc extinguishing chamber is any one of the technical schemes; the two ends of the arc extinguishing chamber along the layered arrangement direction of the grid plates are respectively a front end and a rear end; and the static contact module is close to the rear end of the arc extinguishing chamber.

The invention provides an arc-extinguishing chamber of a circuit breaker, which comprises a plurality of grid sheets in layered arrangement, wherein the grid sheets are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid sheets are gradually reduced according to the sequence of contact arcs in a group of grid sheets which are finally contacted with the arc generated by the circuit breaker in all groups; the length of the grating sheet is the size from one end edge corresponding to the inlet of the arc extinguishing chamber to the opposite other end edge in the grating sheet; the grid plates comprise more than 2 first grid plates which are arranged one by one; a notch is arranged at the eccentric position of the edge of the end part of the first grid sheet corresponding to the inlet of the arc extinguishing chamber, and the two parts at two sides of the notch are different in area and respectively comprise a large arc inlet end and a small arc inlet end; the large arc inlet ends and the small arc inlet ends of two adjacent first grid sheets are alternately arranged.

When the arc extinguishing chamber is applied, the large arc inlet ends and the small arc inlet ends of the adjacent two first grid plates are alternately arranged to form cutting arc edges in staggered arrangement, so that the large arc inlet ends and the small arc inlet ends are repeatedly cut at different times when an arc enters the arc extinguishing chamber.

Meanwhile, the moving contact module and the static contact module in the circuit breaker are just separated and have high arc energy at the moment, the arc energy gradually decreases along with the increase of the separation distance of the moving contact module and the static contact module, in the arc extinguishing chamber, the grid plates are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid plates in a group of grid plates which finally contact the arc generated by the circuit breaker gradually decrease according to the sequence of the contact arcs.

The invention also provides a circuit breaker applying the arc extinguishing chamber, which can reduce the resistance of the arc entering the arc extinguishing chamber and improve the arc extinguishing effect.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a first gate sheet according to an embodiment of the present invention;

fig. 2 is a configuration diagram of a grid sheet in an arc extinguishing chamber according to an embodiment of the present invention;

fig. 3 is an assembly diagram of a first set of grid plates and a second set of grid plates in an arc extinguishing chamber according to an embodiment of the present invention;

FIG. 4 is a top view of the structure shown in FIG. 3;

fig. 5 is an assembly diagram of all the grid plates in the arc extinguishing chamber according to the embodiment of the present invention;

FIG. 6 is a top view of the structure shown in FIG. 5;

fig. 7 is a schematic structural diagram of a second gate sheet according to an embodiment of the present invention;

fig. 8 is a perspective view of an arc extinguishing chamber according to an embodiment of the present invention;

fig. 9 is a front view of an arc chute according to an embodiment of the present invention;

fig. 10 is a left side view of the arc chute of fig. 9;

fig. 11 is a bottom view of the arc chute of fig. 9;

wherein, in fig. 1-11:

first gate sheets 101, 21, 22, 23, 24; a small arc inlet end 111; a notch 112; a large arc inlet end 113; a first set of grid plates 1; a second set of grid plates 2; a third set of grid plates 3; region 4; second gate sheets 31, 32, 33, 34; a "V" shaped region 20; a left arc-separating side plate 102; a left gas production shield 103; an arc striking plate 104; a right arc-separating side plate 105; a right gas production shield 106; and a movable contact module 200.

Detailed Description

The embodiment of the invention discloses an arc extinguishing chamber of a circuit breaker, wherein notches are arranged at the eccentric positions of edges of the ends, corresponding to the inlets of the arc extinguishing chamber, of first grid plates, partial areas on two sides of the notches are different, and the large arc inlet ends and the small arc inlet ends of two adjacent first grid plates are alternately arranged, so that when an arc enters the arc extinguishing chamber, the large arc inlet ends and the small arc inlet ends of the first grid plates are repeatedly cut for multiple times at different times. The embodiment of the invention also discloses a circuit breaker applying the arc extinguishing chamber, which can reduce resistance, enable the arc to enter the arc extinguishing chamber quickly and improve the arc extinguishing speed.

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Referring to fig. 1-11, an embodiment of the present invention provides an arc extinguishing chamber of a circuit breaker, including a plurality of layered gate sheets, where the gate sheets are divided into a plurality of groups along a layered arrangement direction, and lengths of the gate sheets in a group of gate sheets that finally contact an arc generated by the circuit breaker in all groups are gradually reduced according to a sequence of contact arcs; the length of the grating sheet is the dimension from one end edge corresponding to the inlet of the arc extinguishing chamber to the opposite other end edge in the grating sheet, namely the dimension in the up-down direction as shown in fig. 2; the grid plates comprise more than 2 first grid plates 101 which are arranged one by one; a notch 112 is arranged at the edge eccentric position of the end part of the first grid sheet 101 corresponding to the inlet of the arc extinguishing chamber, and two parts on two sides of the notch 112 are different in area and respectively comprise a large arc inlet end 113 and a small arc inlet end 111; the large arc inlet ends 113 and the small arc inlet ends 111 of two adjacent first grid plates 101 are alternately arranged, for example: the small arc-feeding end 111 of one first grating sheet 101 is positioned at the left side of the arc extinguishing chamber, the large arc-feeding end 113 is positioned at the right side of the arc extinguishing chamber, and then the small arc-feeding end 111 of the adjacent first grating sheet 101 is positioned at the right side of the arc extinguishing chamber, and the large arc-feeding end 113 is positioned at the left side of the arc extinguishing chamber. The layered arrangement of the grid sheets refers to a state that adjacent grid sheets are arranged at intervals and the surfaces of the adjacent grid sheets are opposite in surface to surface.

Specifically, two ends of the arc extinguishing chamber along the layered arrangement direction of the grid plates are respectively a rear end and a front end, as shown in fig. 2; the rear end of the arc extinguishing chamber is close to a fixed contact module of the circuit breaker; when the breaker is opened, the moving contact module of the breaker is gradually far away from the fixed contact module and moves to the front end of the arc extinguishing chamber, and the arc follow-up contact module moves to have a moving state from the rear end to the front end of the arc extinguishing chamber, so that the grid sheet in the arc extinguishing chamber sequentially contacts with an arc along the direction from the rear end to the front end of the arc extinguishing chamber. The group of grid plates which finally contact the arc generated by the breaker in all groups is the group of grid plates which are farthest from the fixed contact module of the breaker in all groups, namely the group of grid plates which are farthest from the rear end of the arc extinguishing chamber.

When the arc extinguishing chamber is used, the large arc inlet ends 113 and the small arc inlet ends 111 of the adjacent two first grid sheets 101 are alternately arranged to form staggered cutting arc edges, so that the large arc inlet ends and the small arc inlet ends are repeatedly cut at different times when the arc enters the arc extinguishing chamber.

Meanwhile, the moving contact module and the static contact module in the circuit breaker are just separated and have high arc energy in the moment, the arc energy gradually decreases along with the increase of the separation distance of the moving contact module and the static contact module, in the arc extinguishing chamber, the grid plates are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid plates in a group of grid plates which finally contact the arc generated by the circuit breaker gradually decrease according to the sequence of the contact arcs.

Taking the first grid plates 24, 23, 22 and 21 which are sequentially arranged from the rear end to the front end of the arc extinguishing chamber as an example, the left sides of the first grid plates 22 and 24 are large arc inlet ends 113, the right sides of the first grid plates 21 and 23 are large arc inlet ends 113, and the first grid plates are sequentially arranged from the rear end to the front end to form a V-shaped area 20 which extends inwards from the opening of the arc extinguishing chamber, and the formation of the V-shaped area 20 can reduce the resistance of an electric arc entering the arc extinguishing chamber. In addition, the right arc end area of the V-shaped region 20 is arranged from the rear end to the front end, and is sequentially arranged from small to large to small to large, and when the arc enters the arc extinguishing chamber, the arc is sequentially cut from the rear to the front by the right arc end of the first grid sheet 23 and the grid sheet of the right arc end of the first grid sheet 21; the left arc-entering end of the V-shaped area 20 is arranged from the rear end to the front end, and is sequentially arranged from big to small to big to small, when the arc enters the arc extinguishing chamber, the arc is sequentially cut from the left arc-entering end of the first grid sheet 24 and the left arc-entering end of the first grid sheet 22 from back to front, so that a large arc-entering end 113 with a large area in the first grid sheet is formed, the arc is firstly cut, then the small arc-entering end 111 with a small area is cut, the arc can be cut into longer arc sections when the arc is firstly, the arc is cut into shorter arc sections again after continuously and rapidly entering the arc extinguishing chamber, and the arc voltage is increased, so that the effect of rapidly extinguishing the arc is achieved.

It can be seen that the first grid plate 101 provided in this embodiment can reduce the resistance of the arc entering the arc extinguishing chamber, and increase the speed of the arc entering the arc extinguishing chamber, thereby increasing the arc extinguishing speed.

The arc-extinguishing chamber further comprises a second grid sheet, a notch is arranged in the center of the edge of the end part of the second grid sheet corresponding to the inlet of the arc-extinguishing chamber, and parts on two sides of the notch are symmetrical to each other. The second grid is used for one of the groups that contacts the arc generated by the circuit breaker last.

Preferably, in one group of grid plates (namely, one group of grid plates of the two adjacent groups of grid plates, which are closer to a static contact module of the circuit breaker) of the arc contact, the gap size of the adjacent grid plates is larger, so that all the grid plates are integrally arranged in a rear-sparse front-dense mode; the movable contact module and the fixed contact module of the circuit breaker are separated and instantaneously generate large and more metal particles, the metal particles enter the space between the sparse grid sheets arranged at the rear end of the arc extinguish chamber, the blocking is effectively avoided, the adjacent grid sheets at the rear end of the arc extinguish chamber are prevented from being mutually connected in series to achieve equal potential due to the blocking of the metal particles, the effect of only one grid sheet after the series connection of a plurality of grid sheets is avoided, the effect of each grid sheet is ensured, the arc is cut into more sections, the arc voltage is improved, and the arc extinguishing effect of the arc extinguish chamber is improved.

Specifically, the gap sizes of any two adjacent grid sheets in each group of grid sheets are the same; or the gap size between two adjacent grid plates in each group of grid plates gradually decreases along the sequence of the contact arc (i.e. along the direction from the rear end to the front end of the arc extinguishing chamber), and the embodiment is not limited.

In the arc-extinguishing chamber, the grid plates are divided into three groups, and the first group of grid plates 1, the second group of grid plates 2 and the third group of grid plates 3 are sequentially arranged along the sequence of contact arcs (namely along the rear end to the front end of the arc-extinguishing chamber). The third set of blades 3 is a set of blades that eventually contact the arc generated by the circuit breaker, accounting for approximately one third of the total number of blades.

The distance between adjacent grid plates in the third group of grid plates 3 of about 1/3 is designed to be smaller because the arc energy is gradually weakened along with the separation of the movable contact module and the fixed contact module, generated metal particles are smaller, the third group of grid plates 3 are not easy to block, the distance between the grid plates is designed to be smaller, the unnecessary distance can be distributed to the area needing to be increased, the design according to the requirement is realized, the function of each grid plate is fully exerted, the distance between the grid plates at the rear end can be increased according to the requirement in the arc extinguishing chamber of the same structure, the resistance of an arc entering the arc extinguishing chamber is reduced, the total number of the grid plates is not reduced, and therefore the arc voltage is not reduced, and the arc is easier to cut and extinguish.

The first group of grid plates 1 and the second group of grid plates 2 adopt a first grid plate 101, and the third group of grid plates 3 adopts a second grid plate.

In the arc extinguishing chamber, the ends of the grid plates corresponding to the inlets of the arc extinguishing chamber are sequentially arranged into an arc shape, and the arc shape is consistent with the shape of the moving track of the moving contact module in the circuit breaker, such as the arrangement shape of the ends of the grid plates in the area 4 in fig. 2.

The ends of the grid sheets corresponding to the inlets of the arc-extinguishing chambers are arranged according to the movement track of the moving contact module, so that the moving contact module keeps the same distance as much as possible with the ends of the grid sheets corresponding to the inlets of the arc-extinguishing chambers when being far away from the fixed contact module, the resistance of the electric arc entering the arc-extinguishing chambers is reduced, the effect of each grid sheet is fully exerted, and the effect of quick arc extinction is achieved.

The above-mentioned several grid plates include one or more second grid plates of the first group of grid plates 1, the second group of grid plates 2 and the third group of grid plates 3, which are not limited in this embodiment, and can be specifically designed according to the motion track of the movable contact module.

The arc extinguishing chamber comprises a back plate, a left arc isolation side plate 102 fixed on the back plate and a right arc isolation side plate 105 fixed on the back plate; the two arc-isolation side plates are arranged in parallel and are respectively perpendicular to the back plate; the grid sheets are parallel to each other, two ends of each grid sheet are respectively fixed on the two arc-isolating side plates, and each grid sheet is respectively perpendicular to the backboard. The arc extinguishing chamber further comprises an arc striking plate 104, a left gas production protective cover and a right gas production protective cover, wherein the arc striking plate 104 is fixed at the front ends of the two arc isolation side plates and the front end of the backboard; the left gas production shield 103 is fixed on the left arc-isolating side plate 102 and covers the left sides of all the grid plates, and the right gas production shield 106 is fixed on the right arc-isolating side plate 105 and covers the right sides of all the grid plates.

The explosion chamber that this embodiment provided can make the electric arc get into this explosion chamber inside fast, makes bars timely cutting electric arc to improve arc voltage, force the direct current electric arc to extinguish rapidly, this explosion chamber also can solve the problem that direct current low current was put out the arc difficulty simultaneously, thereby reaches the effect that improves circuit breaker breaking capacity and promotes the contact life.

The embodiment of the invention also provides a circuit breaker, which comprises a shell, and an arc extinguishing chamber, a moving contact module and a fixed contact module which are respectively arranged in the shell, wherein the arc extinguishing chamber is provided by the embodiment; the two ends of the arc extinguishing chamber along the layered arrangement direction of the grid plates are respectively a front end and a rear end; the static contact module is close to the rear end of the arc extinguishing chamber.

The circuit breaker may be a dc circuit breaker or an ac circuit breaker, and the embodiment is not limited.

The circuit breaker provided by the embodiment is applied to the arc extinguishing chamber provided by the embodiment, so that the resistance of an arc entering the arc extinguishing chamber can be reduced, and the arc extinguishing effect is good. Of course, the circuit breaker provided in this embodiment also has other effects related to the arc extinguishing chamber provided in the above embodiment, and will not be described herein.

In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. The arc extinguishing chamber of the circuit breaker comprises a plurality of grid sheets which are arranged in a layered mode, and is characterized in that the grid sheets are divided into a plurality of groups along the layered arrangement direction, and the lengths of the grid sheets are gradually reduced according to the sequence of contacting the electric arcs generated by the circuit breaker in a group of grid sheets which are finally contacted with the electric arcs in all groups; the length of the grid sheet is the size from one end edge of the grid sheet corresponding to the inlet of the arc extinguishing chamber to the opposite other end edge; the grid plates comprise more than 2 first grid plates which are arranged one by one, gaps are arranged at the eccentric positions of edges of the end parts of the first grid plates, which correspond to the inlets of the arc extinguishing chambers, and the two parts on two sides of the gaps are different in area and are respectively a large arc inlet end and a small arc inlet end; the large arc inlet ends and the small arc inlet ends of two adjacent first grid sheets are alternately arranged.

2. The arc chute according to claim 1, wherein the grating sheet further comprises a second grating sheet, a gap is arranged in the center of the edge of the end part of the second grating sheet corresponding to the inlet of the arc chute, and the two sides of the gap are symmetrical.

3. The arc chute according to claim 2, wherein the grid plates are divided into three groups, the first, second, and third groups of grid plates being sequentially arranged in the order of contact with the arc; wherein the first grid plates are adopted by the first group of grid plates and the second group of grid plates respectively; the third set of gate sheets employs the second gate sheet.

4. The arc chute of claim 1 wherein the gap size of adjacent ones of the two adjacent sets of grids that first contact the arc is greater.

5. The arc chute of claim 4 wherein the gap size of any adjacent two of said grids in each set is the same.

6. The arc chute of claim 4 wherein in each set of said grids, the gap size between adjacent two of said grids decreases progressively in the order of contact with said arc.

7. The arc chute according to claim 1, wherein the ends of the plurality of gate sheets corresponding to the inlet of the arc chute are sequentially arranged in an arc shape, and the arc shape is consistent with the shape of the moving track of the moving contact module in the circuit breaker.

8. The arc chute of claim 1 wherein the arc chute comprises a back plate, a left arc-isolating side plate secured to the back plate and a right arc-isolating side plate secured to the back plate; two ends of each grid sheet are respectively fixed on the two arc-isolation side plates, and each grid sheet is respectively perpendicular to the backboard.

9. The arc chute of claim 8 further comprising an arc striking plate, a left gas shield, and a right gas shield; the arc striking plate is fixed at one end, far away from the fixed contact module of the circuit breaker, of the two arc isolating side plates and the backboard; the left gas production protective cover is fixed on the left arc isolation side plate and covers the left sides of all the grid plates; the right gas production protective cover is fixed on the right arc isolation side plate and covers the right sides of all the grid plates.

10. A circuit breaker comprising a housing, and an arc extinguishing chamber, a moving contact module and a fixed contact module respectively mounted in the housing, characterized in that the arc extinguishing chamber is the arc extinguishing chamber according to any one of claims 1-9; the two ends of the arc extinguishing chamber along the layered arrangement direction of the grid plates are respectively a front end and a rear end; and the static contact module is close to the rear end of the arc extinguishing chamber.