A circuit breaker structure with improved breaking capacity

Abstract

The utility model relates to a kind of breaker structure of improving breaking capacity, it is characterized by: the position corresponding with arc-extinguishing chamber (8) on the inside surface of the shell of breaker is equipped with boss (B). By improving the relevant structure of breaker, arc is accelerated to enter arc-extinguishing chamber and discharge breaker.

Description

Technical Field

[0001] The present invention belongs to the technical field of circuit breakers, and in particular relates to a circuit breaker structure with improved breaking capacity. Background Art

[0002] Circuit breakers are a vital component of power distribution systems, primarily used in industrial low-voltage power systems. They connect and disconnect current in power grid circuits and protect power lines and power equipment from faults such as overloads, undervoltages, short circuits, and single-phase grounding. The circuit breaker's function of interrupting overload or short-circuit currents is primarily accomplished through its operating system, electromagnetic system, contact system, and arc extinguishing system. When a fault current flows through the circuit and exceeds the set value, the operating mechanism is actuated, rapidly opening the circuit breaker's moving and stationary contacts. The voltage across these contacts then causes a discharge in the air, generating a high-temperature arc. The arc's combustion causes the air temperature within the arc extinguishing device to rise sharply, accelerating air ionization. Furthermore, the arc, driven by the magnetic field and fluid effects within the arc extinguishing chamber, is separated into multiple short arcs by arc-isolating grids. The metal arc-isolating grids enhance the arc's deionization effect, reducing the arc size and rapidly increasing the voltage, ultimately extinguishing the arc. In order to improve the arc extinguishing performance of the arc extinguishing chamber, it is generally necessary to allow the arc to quickly enter the arc extinguishing grid of the arc extinguishing chamber through the arc channel so that the grid can effectively cut the arc, thereby achieving the goal of quickly extinguishing the arc.

[0003] Existing circuit breakers typically use a combination of a housing, moving contacts, stationary contacts, arc-striking plates, magnetic plates, arc-isolating plates, and an arc-extinguishing chamber to form an arc channel and arc-extinguishing system. When a high short-circuit current flows through the circuit breaker, the arc-striking plates guide the arc into the arc-extinguishing chamber to extinguish the arc, thereby protecting the circuit and electrical equipment. However, in existing circuit breakers, when a high short-circuit current flows through the circuit breaker, the arc transfer between the moving and stationary contacts is too slow or nonexistent, resulting in extensive burn damage to the moving and stationary contacts and the circuit breaker failing without power. Furthermore, the arc nozzle is prone to clogging, preventing the arc from entering the arc-extinguishing chamber, which can burn the bimetallic element and cause the circuit breaker to fail to meet performance standards. Summary of the Invention

[0004] The present invention aims to address the aforementioned existing problems in circuit breakers where, when a high short-circuit current passes through the circuit breaker, the arc transfer between the moving and static contacts is slow or nonexistent, resulting in significant contact burnout and circuit breaker failure. Furthermore, the arc nozzle is prone to clogging, preventing the arc from entering the arc extinguishing chamber, which in turn burns the bimetallic element and causes substandard circuit breaker performance. The present invention provides a circuit breaker structure with enhanced breaking capacity. By improving the relevant circuit breaker structures, the arc is accelerated to enter the arc extinguishing chamber and exit the circuit breaker.

[0005] Technical Solution

[0006] In order to achieve the above technical objectives, the present invention provides a circuit breaker structure with improved breaking capacity, characterized in that a boss is provided on the inner side of the circuit breaker housing at a position corresponding to the arc extinguishing chamber.

[0007] Furthermore, the housing of the circuit breaker includes the base and the cover, and the boss at least includes a boss 1 provided on the inner side surface of the base at a position corresponding to the arc extinguishing chamber.

[0008] Furthermore, a second boss is provided on the inner side surface of the cover at a position corresponding to the arc extinguishing chamber.

[0009] Furthermore, the boss 1 and the boss 2 are located on the left and right sides of the arc extinguishing chamber and are arranged symmetrically or diagonally.

[0010] Furthermore, the arc nozzle located on the outer side of the tail of the arc extinguishing chamber in the inner cavity of the circuit breaker housing has a width of not less than 1 mm and a depth of not less than 2 mm.

[0011] Furthermore, the arc striking piece extends upward toward the bending portion of the moving contact to form an arc striking angle.

[0012] Furthermore, the arc striking angle is in an inverted U shape, and the distance between the end of the arc striking angle opposite to the moving contact and the moving contact is no more than 3 mm. This structure is advantageous for transferring the arc.

[0013] Furthermore, the outer side surface of the static contact mounting end is lower than the highest point or line of its own curved end surface, and the end of the arc angle of the static contact extends toward the arc extinguishing chamber. This structure facilitates the transfer of the arc generated when the moving and static contacts are opened to the arc channel; it facilitates the transfer of the arc generated when the moving and static contacts are opened to the arc channel, thereby entering the arc extinguishing chamber;

[0014] Furthermore, an insulating sheet is provided in the circuit breaker, one end of the insulating sheet is installed between the moving contact and the bimetallic sheet, and the other end extends to a position between the arc striking sheet and the bimetallic sheet;

[0015] The other end of the insulating sheet is close to the arc striking sheet to seal the gap around the moving contact and the arc striking sheet. With this structure, the arc is more easily transferred to the arc channel and enter the arc extinguishing chamber.

[0016] Furthermore, a convex rib is provided on the surface of the arc striking piece facing the arc extinguishing chamber to reduce the distance between the arc striking piece and the arc striking end of the static contact. This structure can reduce the arc root area, thereby reducing the arc diameter, which is beneficial for arc transfer.

[0017] Beneficial effects

[0018] The present invention provides a circuit breaker structure with improved breaking capacity. The arc nozzle of the base / cover is deepened and a boss is added. The arc extinguishing chamber is moved forward and tightened to prevent the arc extinguishing grid from burning the arc nozzle plastic and melting and clogging it. The arc channel is smooth and easy to discharge. The arc striking angle is increased to approach the moving contact. The shape of the arc striking angle of the static contact plate is changed. This facilitates the transfer of the arc generated when the moving and static contacts are broken into the arc channel and thus into the arc extinguishing chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Attachment Figure 1 It is a schematic diagram of the internal structure of the circuit breaker in Example 1 of the present invention.

[0020] Attachment Figure 2 This is a schematic diagram of the position of the arc-separating rib in Example 1 of the present invention.

[0021] Attachment Figure 3 It is a schematic diagram of the positions of the first recess, the second recess and the static contact in Example 1 of the present invention.

[0022] Attachment Figure 4 This is a schematic diagram of the installation of the insulating sheet in Example 1 of the present invention.

[0023] Attachment Figure 5 This is a schematic diagram of the position of the convex rib on the arc striking angle in Example 1 of the present invention.

[0024] Attachment Figure 6 This is a schematic diagram of the position of the boss on the arc striking angle in Example 1 of the present invention.

[0025] Attachment Figure 7 Schematic diagram of the arc angle end position of the static contact in Example 1 of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "inner" and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted" and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0029] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0030] Example 1

[0031] As attached Figure 1 As shown in the figure, this embodiment provides an improved structure for the electrical life of a circuit breaker. The housing W of the circuit breaker includes the base 1 and the cover 2. The static contact 3 is fixedly installed in the chamber formed by the base 1 and the cover 2. Figure 2 As shown in Figures 3 and 4, a recess 1a01 is provided on the inner side surface of the base 1 where the arc-isolating rib 1a and the static contact 3 match. A recess 2a01 is provided on the inner side surface of the cover 2 where the arc-isolating rib 2a and the static contact 3 match. In this embodiment, the corners of the arc-isolating rib 1a and the arc-isolating rib 2a are rounded. Recess 1a01 and Recess 2a01 are recessed planes. The gap between the side surface of the static contact 3 corresponding to the recess 1a01 and the recess 2a01 is no less than 0.2 mm. The recess 1a01 and Recess 2a01 can be used to increase the creepage distance.

[0032] like Figure 1 and 6 As shown, a boss B is provided on the inner side surface of the circuit breaker casing at a position corresponding to the arc extinguishing chamber 8. Boss B includes boss 1b and boss 2b. Specifically, boss 1b is provided on the inner side surface of the base 1 at a position corresponding to the arc extinguishing chamber 8, and boss 2b is provided on the inner side surface of the cover 2 at a position corresponding to the arc extinguishing chamber 8. In this embodiment, there are preferably two bosses 1b and two bosses 2b, and the bosses 1b and 2b are symmetrically arranged on the left and right sides of the arc extinguishing chamber 8. Boss B moves the arc extinguishing chamber 8 forward and tighter, preventing the arc extinguishing grid from directly contacting the arc nozzle, preventing the arc extinguishing grid from scalding the arc nozzle plastic and melting and clogging, and making the arc channel smoother and easier to discharge;

[0033] As attached Figure 1 As shown, the arc nozzle 9 located on the outer side of the tail of the arc extinguishing chamber 8 in the inner cavity of the circuit breaker housing is not less than 1 mm wide and not less than 2 mm deep to facilitate smooth discharge of the arc.

[0034] As attached Figure 1 and4 As shown, one end of the insulating sheet 4 is installed between the moving contact 5 and the bimetallic strip 6, and the other end extends to the position between the arc-striking strip 7 and the bimetallic strip 6. The other end of the insulating sheet 4 is close to the arc-striking strip 7 to seal the gap around the moving contact 5 and the arc-striking strip 7. The insulating sheet seals the arc channel, making it easier for the arc to transfer through the arc channel and enter the arc extinguishing chamber.

[0035] As attached Figure 1 and 5 As shown, the arc striking piece 7 extends upward toward the bend of the moving contact 5 to form an arc striking angle 701. The arc striking angle 701 is in an inverted U-shape. A rib 7a is provided on the surface of the arc striking piece 7 facing the arc extinguishing chamber 8 to reduce the distance between the arc striking piece 7 and the arc striking end 3a of the static contact 3, thereby reducing the arc root area and the arc diameter, which is beneficial for arc transfer. The distance between the end of the arc striking angle 701 opposite to the moving contact 5 and the moving contact 5 is no more than 3 mm. As shown in the attached figure, Figure 1 and 7 As shown, the outer side surface 3b of the mounting end of the static contact 3 is lower than the highest point or line of its own curved end surface 3c. The arc angle end of the static contact 3 extends toward the arc extinguishing chamber 8. The minimum distance between the arc angle end 3d of the static contact 3 and the V-shaped end 8a of the arc extinguishing grid at the top of the arc extinguishing chamber 8 is no less than 0.3mm. This facilitates the transfer of arcs generated during the opening and closing of the moving and static contacts into the arc channel and into the arc extinguishing chamber.

[0036] Example 2

[0037] In another embodiment provided herein, boss B comprises only boss 1b on the inner side of base 1, corresponding to arc extinguishing chamber 8. Boss B moves arc extinguishing chamber 8 forward and tightens it, preventing direct contact between the arc quenching grid and the arc nozzle, thus preventing burns from the arc quenching grid and the melting of the arc nozzle plastic, thereby ensuring a smooth arc path and facilitating discharge. The remaining structure is the same as in the previous embodiment.

[0038] Example 3

[0039] In another embodiment provided by the present invention, the boss 1b and the boss 2b are located on the left and right sides of the arc extinguishing chamber 8 and are arranged diagonally. There is preferably one boss 1b and one boss 2b. The other structures are the same as those in embodiment 1.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circuit breaker structure with improved breaking capacity, characterized by: A boss (B) is provided on the inner side of the circuit breaker housing at a position corresponding to the arc extinguishing chamber (8) to move the arc extinguishing chamber (8) forward and tighten it, thereby preventing the arc extinguishing grid from directly contacting the arc nozzle, preventing the arc extinguishing grid from scalding the arc nozzle plastic and melting and clogging it, and making the arc channel smoother and easier to discharge; The outer shell of the circuit breaker comprises a base (1) and a cover (2), wherein the boss (B) comprises at least a boss 1 (1b) provided on the inner side surface of the base (1) at a position corresponding to the arc extinguishing chamber (8); A second boss (2b) is provided on the inner side surface of the cover (2) at a position corresponding to the arc extinguishing chamber (8); A first recess (1a01) is provided at a position where the arc-isolating rib (1a) on the inner side surface of the base (1) and the static contact (3) are in engagement with each other, and a second recess (2a01) is provided at a position where the arc-isolating rib (2a) on the inner side surface of the cover (2) and the static contact (3) are in engagement with each other.

2. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: The boss 1 (1b) and the boss 2 (2b) are located on the left and right sides of the arc extinguishing chamber (8) and are arranged symmetrically or diagonally.

3. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: The arc nozzle (9) located on the outer side of the tail of the arc extinguishing chamber (8) in the inner cavity of the circuit breaker shell has a width of not less than 1 mm and a depth of not less than 2 mm.

4. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: The arc striking piece (7) extends upwards towards the bending position of the moving contact (5) to form an arc striking angle (701).

5. A circuit breaker structure with improved breaking capacity according to claim 4, characterized in that: The arc striking angle (701) is in an inverted U shape, and the distance between the end of the arc striking angle (701) opposite to the moving contact (5) and the moving contact (5) is no more than 3 mm.

6. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: The outer side surface (3b) of the mounting end of the static contact (3) is lower than the highest point or line of its own curved end surface (3c), and the arc angle end (3d) of the static contact (3) extends toward the arc extinguishing chamber (8).

7. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: An insulating sheet (4) is provided in the circuit breaker, one end of the insulating sheet (4) is installed between the moving contact (5) and the bimetallic sheet (6), and the other end extends to a position between the arc-starting sheet (7) and the bimetallic sheet (6); The other end of the insulating sheet (4) is in close contact with the arc striking sheet (7) to seal the gap around the moving contact (5) and the arc striking sheet (7).

8. A circuit breaker structure with improved breaking capacity according to claim 1, characterized in that: A convex rib (7a) is provided on the surface of the arc striking piece (7) facing the arc extinguishing chamber (8) to reduce the distance between the arc striking piece (7) and the arc striking end (3a) of the static contact (3).

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