Circuit breaker arc extinguish chamber exhaust structure

Abstract

A circuit breaker arc extinguish chamber exhaust structure comprises an arc extinguish chamber, an insulation fence is arranged on the exhaust side of an arc extinguish grid piece in the arc extinguish chamber, and the circuit breaker arc extinguish chamber exhaust structure is characterized in that air holes with different hole areas are formed in the insulation fence; the opening area of the first air hole in the insulating fence close to the opening area of the moving contact and the static contact is smaller than the opening area of the second air hole in the insulating fence away from the opening area of the moving contact and the static contact. An unequal-air-hole fence structure is adopted; the air holes with different sizes are designed at different positions of the fence, and the air pressure of the corresponding stagnation position of the arc extinguish chamber is increased, so that the air blowing at the position is increased, the movement of the arc is accelerated, and meanwhile, the back adhesion of the grid sheet is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of circuit breakers, and particularly relates to an exhaust structure of an arc extinguishing chamber of a circuit breaker. Background Art

[0002] The function of a circuit breaker to interrupt overload or short - circuit current is mainly completed by an operating system, an electromagnetic system, a contact system, and an arc extinguishing system installed in the circuit breaker. When a fault current appears in the circuit and the current value exceeds the set value range, the operating mechanism is driven to act, so that the moving and static contacts of the circuit breaker are quickly disconnected. At this time, the voltage between the moving and static contacts causes the air medium to discharge, thus generating a high - temperature arc. During the combustion process of the arc, the air temperature in the arc extinguishing device rises sharply, accelerating the ionization of the air. On the other hand, under the promotion of the magnetic field and fluid effect in the arc extinguishing chamber, the arc is separated into multiple short arcs by multiple arc - separating grid plates, and the de - ionization effect of the arc is strengthened by the metal arc - separating plates. The arc becomes smaller and the voltage rises rapidly, causing the arc to extinguish. To improve the arc extinguishing performance of the arc extinguishing chamber, generally, the arc is required to quickly enter the arc - separating grid plates of the arc extinguishing chamber through the arc passage, so that the grid plates can effectively cut the arc, thereby achieving the goal of quickly extinguishing the arc, and then quickly discharging through the exhaust passage out of the circuit breaker housing. In the arc extinguishing chamber of existing small - sized circuit breaker products, the air holes on the insulating fence on the exhaust side of the arc - separating grid plates are of the same size. When the static end or the moving end is a long arc - starting structure, the air - blowing force is insufficient, the arc is difficult to move, resulting in difficult arc - starting at the moving and static ends of the contact system.

[0003] Chinese Patent CN107863282 A discloses an arc extinguishing chamber of a circuit breaker, which includes arc - separating walls arranged oppositely, an insulating plate connecting the arc - separating walls, and arc - separating grid plates. The arc - separating grid plates are arranged in the arc extinguishing chamber formed by the arc - separating walls and the insulating plate. The characteristics are as follows: The arc extinguishing chamber of the circuit breaker is also provided with an arc extinguishing cover. A magnetic field is formed between the arc - separating walls. The arc extinguishing cover includes a transverse plate arranged above the arc extinguishing chamber and a vertical plate attached to the arc - separating walls. A convex platform protruding towards the arc extinguishing chamber is arranged in the middle of the front edge of the transverse plate. A groove is opened in the convex platform, and a magnetic steel is arranged in the groove. The vertical plate forms a first transverse surface and a second transverse surface. The part between the first transverse surface and the second transverse surface forms a support leg, and the number of arc - separating grid plates arranged within the height range of the support leg is 1 / 3 of the total number of arc - separating grid plates. This arc extinguishing chamber ensures that the hot air flow generated during arc extinguishing can be cooled and dissipated in time, but for a long arc - starting structure at the static end or the moving end, the arc is still difficult to move. Summary of the Utility Model

[0004] The object of the present utility model is to address the defect that the pores on the insulating fence provided on the exhaust side of the arc extinguishing grid in the existing arc extinguishing chamber are of the same size, resulting in insufficient air blowing force and difficult movement of the electric arc when the static end or the moving end has a long arc ignition structure. A circuit breaker arc extinguishing chamber exhaust structure is provided, adopting an unequal pore fence structure; by designing pores of different sizes at different positions of the fence, the air pressure at the corresponding stagnant position in the arc extinguishing chamber is increased, thereby increasing the air blowing at this position and accelerating the movement of the electric arc.

[0005] Technical solution

[0006] To achieve the above technical purpose, the present utility model provides a circuit breaker arc extinguishing chamber exhaust structure, which includes an arc extinguishing chamber. An insulating fence is provided on the exhaust side of the arc extinguishing grid in the arc extinguishing chamber. It is characterized in that: pores with different opening areas are provided on the insulating fence, and the opening area of pore one on the insulating fence near the area where the moving contact and the static contact open to generate an electric arc is smaller than the opening area of pore two on the insulating fence far from the area where the moving contact and the static contact open to generate an electric arc.

[0007] In one embodiment, the area where the moving contact and the static contact open to generate an electric arc is close to one end of the insulating fence, such that the arc ignition distance of the corresponding moving contact or static contact is shorter than the arc ignition distance of the corresponding static contact or moving contact. The opening area of the pores on the insulating fence gradually increases from the end corresponding to the shorter arc ignition distance to the end corresponding to the longer arc ignition distance.

[0008] In one embodiment, the area where the moving contact and the static contact open to generate an electric arc is at the middle position of the insulating fence, such that the arc ignition distance of the corresponding moving contact or static contact is the same as the arc ignition distance of the corresponding static contact or moving contact. The area of the pores on the insulating fence gradually increases from the middle to both ends.

[0009] In one embodiment, pore two includes a first pore two and a second pore two, and the opening area of the first pore two is less than or equal to the opening area of the second pore two.

[0010] In one embodiment, the insulating fence and the housing are of an integral structure.

[0011] Beneficial effects

[0012] The present utility model provides an exhaust structure for a circuit breaker arc extinguishing chamber, which includes an arc extinguishing chamber. An insulating fence is arranged on the exhaust side of the arc extinguishing grids in the arc extinguishing chamber, and air holes with different opening areas are arranged on the insulating fence. The opening area of air hole one on the insulating fence near the area where the moving contact and the static contact are opened to generate an arc is smaller than the opening area of air hole two on the insulating fence far from the area where the moving contact and the static contact are opened to generate an arc. An unequal air hole fence structure is adopted; by designing air holes of different sizes at different positions of the fence, the air pressure at the corresponding stagnant position in the arc extinguishing chamber is increased, thereby increasing the air blowing at this position, accelerating the movement of the arc, and at the same time avoiding adhesion behind the grids. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present utility model, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0014] FIG Figure 1 is a schematic diagram of the exhaust passage in Embodiment 1 of the present utility model.

[0015] FIG Figure 2 is a schematic diagram of the air holes in the insulating fence in Embodiment 1 of the present utility model.

[0016] FIG Figure 3 is a schematic diagram of the air holes in the insulating fence in Embodiment 2 of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0018] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be an intermediate component at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in the description of the present application are only for the purpose of illustration and do not represent the only implementation.

[0019] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0020] In this application, unless otherwise clearly specified and defined, the first feature may be in direct contact with the second feature or in indirect contact with the second feature through an intermediate medium when the first feature is "on" or "under" the second feature. Moreover, when the first feature is "above", "over" or "on top of" the second feature, the first feature may be directly above or diagonally above the second feature, or merely indicate that the horizontal height of the first feature is higher than that of the second feature. When the first feature is "below", "beneath" or "underneath" the second feature, the first feature may be directly below or diagonally below the second feature, or merely indicate that the horizontal height of the first feature is lower than that of the second feature.

[0021] Unless otherwise defined, all technical and scientific terms used in the description of this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the description of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The term "and / or" used in the description of this application includes any and all combinations of one or more of the related listed items.

[0022] Embodiment 1

[0023] As shown in the Figure 1 accompanying drawings, an exhaust structure of a circuit breaker arc extinguishing chamber includes an arc extinguishing chamber 1. An insulating fence 3 is provided on the exhaust side of the arc extinguishing grid 2 in the arc extinguishing chamber 1. The insulating fence 3 is provided with air holes having different opening areas. The opening area of the air hole 3a (the first air hole) on the insulating fence 3 near the opening area of the moving contact 4 and the static contact 5 is smaller than the opening area of the air hole 3b (the second air hole) on the insulating fence 3 far from the opening area of the moving contact 4 and the static contact 5. The opening area of the first air hole 3b01 is less than or equal to the opening area of the second air hole 3b02. In this embodiment, the opening area of the first air hole 3b01 is smaller than the opening area of the second air hole 3b02.

[0024] As shown in the Figure 2As shown in the figure, in this embodiment, in the housing 6 of the circuit breaker, the insulating barrier 3 and the housing 6 are of an integral structure. The region where the moving contact 4 and the static contact 5 generate an arc when opened is arranged at one end close to the insulating barrier 3, and this end is relatively close to the moving contact 4, so that the arc-drawing distance of the corresponding moving contact 4 is shorter than that of the corresponding static contact 5. The opening area of the air holes on the insulating barrier 3 gradually increases from the end corresponding to the shorter arc-drawing distance to the end corresponding to the longer arc-drawing distance.

[0025] When this end of the insulating barrier 3 is relatively close to the static contact 5, the arc-drawing distance of the static contact 5 is shorter than that of the moving contact 4, and the opening area of the air holes on the insulating barrier 3 also gradually increases from the end corresponding to the shorter arc-drawing distance to the end corresponding to the longer arc-drawing distance. This structure increases the air pressure at the corresponding position of the arc extinguishing chamber, and solves the problem of arc transfer through the air pressure difference.

[0026] The working principle of this embodiment is as follows: When the static arc-drawing path extends too long to one side, the arc is likely to stagnate at the middle position of the static arc-drawing path. Therefore, the opening area of the exhaust holes of the insulating barrier 1 increases in sequence from the static end to the moving end. When the gas enters the air duct from the arc extinguishing chamber 1, it will preferentially enter from the static end, and then drive the arc to transfer to the moving end; similarly, when the moving arc-drawing path extends too long to one side, the arc is likely to stagnate at the middle position of the moving arc-drawing path. Therefore, the opening area of the exhaust holes of the insulating barrier 1 increases from the moving end to the static end. When the gas enters the air duct from the arc extinguishing chamber 1, it will preferentially enter from the moving end, and then drive the arc to transfer to the static end. 。

[0027] Embodiment 2

[0028] As shown in the attached Figure 3 figure, when the opening area between the moving contact 4 and the static contact 5 is in the middle of the insulating barrier 3, the arc-drawing distance of the corresponding moving contact 4 or static contact 5 is the same as that of the corresponding static contact 5 or moving contact 4. The area of the air holes on the insulating barrier 3 gradually increases from the middle to both ends, that is, the opening area of the middle air hole 3c is smaller than that of the two side air holes 3d. The gas has a strong air-blowing force to blow the arc towards both the static and moving ends, thereby accelerating the arc-drawing at both the static and moving ends.

[0029] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0030] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A circuit breaker arc extinguishing chamber exhaust structure, comprising an arc extinguishing chamber (1), wherein an insulating fence (3) is provided on the exhaust side of an arc extinguishing grid (2) in the arc extinguishing chamber (1), characterized in that: The insulating fence (3) is provided with air holes of different opening areas, and the opening area of ​​air hole 1 (3a) on the insulating fence (3) close to the moving contact (4) and the stationary contact (5) to open the arc generating area is smaller than the opening area of ​​air hole 2 (3b) on the insulating fence (3) far from the moving contact (4) and the stationary contact (5) to open the arc generating area.

2. A circuit breaker arc extinguishing chamber exhaust structure according to claim 1, characterized in that: The area where the moving contact (4) and the stationary contact (5) are opened to generate an arc is close to one end of the insulating fence (3), so that the arc striking distance of the corresponding moving contact (4) or stationary contact (5) is shorter than the arc striking distance of the corresponding stationary contact (5) or moving contact (4), and the opening area of ​​the air hole on the insulating fence (3) gradually increases from the end corresponding to the short arc striking distance to the end corresponding to the long arc striking distance.

3. The circuit breaker arc extinguishing chamber exhaust structure according to claim 1, characterized in that: The arc-generating area when the moving contact (4) and the stationary contact (5) are opened is located in the middle of the insulating fence (3), so that the arc-starting distance of the corresponding moving contact (4) or stationary contact (5) is the same as the arc-starting distance of the corresponding stationary contact (5) or moving contact (4), and the area of ​​the air holes on the insulating fence (3) gradually increases from the middle to both ends.

4. The circuit breaker arc extinguishing chamber exhaust structure according to claim 1, characterized in that: The second pore (3b) comprises a first pore (3b01) and a second pore (3b02), and the opening area of ​​the first pore (3b01) is smaller than or equal to the opening area of ​​the second pore (3b02).

5. The circuit breaker arc extinguishing chamber exhaust structure according to claim 1, characterized in that: The insulating fence (3) and the shell (6) are an integrated structure.

Images