An equipotential moving arc-starting plate, arc-extinguishing system and circuit breaker

Abstract

The utility model discloses an equipotential moving arc-starting plate, an arc-extinguishing system and a circuit breaker, wherein the moving arc-starting plate comprises a connecting portion, a guiding portion and an arc-burning portion; the arc-burning portion is used to be arranged at the end of an arc-extinguishing chamber, and there is a gap between the arc-burning portion and the arc-extinguishing grid at the uppermost end of the arc-extinguishing chamber; the guiding portion is arranged on a side of the arc-burning portion close to the moving contact, and is located above the opening position of the moving contact, and the guiding portion is used to guide the moving arc root to the moving arc-starting plate; the connecting portion is connected to the guiding portion and is located on one side of the moving contact, the end of the connecting portion extends toward the rear of the moving contact, and the connecting portion is connected to the moving contact at an equipotential; when the circuit breaker breaks a fault current, an arc is generated, and the equipotential moving arc-starting plate is used to completely transfer the arc root of the moving contact from the moving contact, thereby avoiding the arc from burning the moving contact material, which can greatly improve the circuit breaker's breaking capacity, improve the operating reliability, and solve the problem of the arc burning the moving contact material.

Description

Technical Field

[0001] The utility model relates to the technical field of low-voltage electrical appliances, and in particular to an equipotential moving arc-starting plate, an arc-extinguishing system and a circuit breaker. Background Art

[0002] Molded case circuit breakers are important control and protection equipment in the field of low-voltage power distribution. With the continuous improvement of the performance requirements of the power industry for low-voltage electrical appliances, miniaturization, high performance and high reliability have become the important technical development direction of molded case circuit breakers at this stage. Among them, the breaking capacity of high voltage and high current is an important indicator of molded case circuit breakers, and the key link of its design is the arc extinguishing system design of the molded case circuit breaker.

[0003] During the breaking process, a high-temperature arc will inevitably be generated between the moving and static contacts. The arc will cause erosion of the contact material, affecting the reliable operation of the circuit breaker. How to protect the contacts and reduce or even avoid the erosion of the contacts by the arc has long been a technical difficulty in this field. Utility Model Content

[0004] In view of the problems existing in the prior art, the utility model provides an equipotential moving arc-starting plate, an arc extinguishing system and a circuit breaker. The technical solution utilizes the equipotential moving arc-starting plate to completely transfer the arc root of the moving contact from the moving contact, thereby solving the problem of arc ablation of the moving contact material.

[0005] The utility model is realized by the following technical solutions:

[0006] An equipotential dynamic arc-starting plate, the equipotential arc-starting plate comprising a connecting portion, a guiding portion and an arc-burning portion;

[0007] The arc burning part is arranged at the end of the arc extinguishing chamber, and there is a gap between the arc burning part and the arc extinguishing grid at the uppermost end of the arc extinguishing chamber;

[0008] The guide part is arranged on a side of the arc burning part close to the moving contact and is located above the opening position of the moving contact. The guide part is used to guide the moving arc root to the moving arc striking plate;

[0009] The connecting portion is connected to the guiding portion and is located at one side of the moving contact. The end of the connecting portion extends to the rear of the moving contact. The connecting portion and the moving contact are connected to the same potential.

[0010] Preferably, the guide portion is a flat plate structure, or a V-shaped or U-shaped structure extending toward the moving contact, which is used to shorten the distance between the guide portion and the moving contact so that the moving arc root is transferred to the guide portion.

[0011] Preferably, plug-in parts are provided on both sides of the arc burning part, and the plug-in parts are used to be plugged and fixed with the insulating clamping plates of the arc extinguishing chamber.

[0012] Preferably, one end of the plug-in portion is connected to the side end of the arc burning portion, and the other end extends toward the guide portion, and an open groove is formed between the plug-in portion and the arc burning portion.

[0013] Preferably, the end of the arc burning portion close to the guide portion does not exceed the end of the arc extinguishing grid.

[0014] Preferably, the connection portion is connected to the moving contact in a flexible connection manner to have the same potential.

[0015] Preferably, a connection area is provided on the connection portion, one end of the soft wire is connected to the connection area, and the other end is connected to the moving contact, or to the conductive portion connected to the moving contact.

[0016] An arc extinguishing system comprises an arc extinguishing chamber, a moving contact, a static contact, a static arc-striking plate and the equipotential moving arc-striking plate.

[0017] The arc extinguishing chamber is located in the radial extension direction of the opening and closing movement trajectory of the moving contact, and the arc extinguishing chamber is located between the moving arc striking plate and the static arc striking plate, the static arc striking plate and the static contact are connected to the same potential, and the moving arc striking plate and the moving contact are connected to the same potential.

[0018] Preferably, the arc extinguishing chamber comprises an arc extinguishing grid, an insulating clamping plate and a gas outlet baffle;

[0019] Two insulating clamps are arranged in parallel and at intervals, and a plurality of arc extinguishing grids are fixed between the two insulating clamps from top to bottom. The air outlet baffle is installed at one end of the arc extinguishing grid away from the moving contact, and a plurality of air outlet holes are opened on the air outlet baffle 303.

[0020] A circuit breaker comprises a circuit breaker body and an arc extinguishing system, wherein the equipotential moving arc striking plate is installed on the arc extinguishing system.

[0021] Compared with the prior art, the utility model has the following beneficial technical effects:

[0022] The utility model provides an equipotential moving arc-starting plate, comprising an arc-burning portion, a guiding portion and a connecting portion connected in sequence, the moving arc-starting plate is connected to the moving contact at the same potential through the connecting portion, the guiding portion is located above the opening position of the moving contact, the arc-burning portion is arranged at the end of the arc extinguishing chamber, an arc is generated when the circuit breaker breaks the fault current, when the arc contacts the guiding portion of the moving arc-starting plate, the current is transferred from the moving contact to the soft-connected moving arc-starting plate, and then the moving arc root of the arc is transferred from the moving contact to the guiding portion of the moving arc-starting plate, as the arc further moves toward the arc extinguishing chamber, the moving arc root of the moving contact can be completely transferred from the moving contact by using the equipotential moving arc-starting plate, thereby avoiding the arc from ablation of the moving contact material, which can greatly improve the circuit breaker breaking capacity and improve the operating reliability, at the same time, the scheme reduces the requirement for the ablation resistance of the moving contact material, is easy to implement and has low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the arc extinguishing device of the utility model;

[0024] Figure 2 This is a schematic structural diagram of a moving arc-starting plate in Embodiment 1 of the utility model;

[0025] Figure 3 This is a schematic structural diagram of a moving arc-starting plate in Embodiment 2 of the present utility model;

[0026] Figure 4 This is a schematic structural diagram of a moving arc-starting plate in Embodiment 3 of the present utility model;

[0027] Figure 5 It is a structural schematic diagram of the arc extinguishing chamber of the utility model;

[0028] Figure 6 It is a structural schematic diagram of the static contact and the arc extinguishing chamber of the utility model;

[0029] Figure 7 It is a structural schematic diagram of the static contact and the static arc-starting plate of the utility model.

[0030] In the figure: moving arc-striking plate 1, moving contact 2, arc extinguishing chamber 3, soft wire 4, static contact 5, static arc-striking plate 6, connecting part 101, guiding part 102, arc burning part 103, arc extinguishing grid 301, insulating clamping plate 302, gas outlet baffle 303. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below in conjunction with the accompanying drawings, which are intended to explain the present invention rather than to limit it.

[0032] An equipotential moving arc-starting plate is used for guiding and transferring the arc root of a moving contact to an arc extinguishing chamber. The equipotential moving arc-starting plate comprises a connecting portion 101, a guiding portion 102 and an arc burning portion 103.

[0033] The arc burning portion 103 is used to be arranged at the end of the arc extinguishing chamber, and there is a gap between it and the arc extinguishing grid at the upper end of the arc extinguishing chamber; the guide portion 102 is arranged on the side of the arc burning portion 103 close to the moving contact, and is located above the opening limit position of the moving contact;

[0034] The connecting portion 101 is connected to the guiding portion 102 and is located at one side of the moving contact. The end of the connecting portion 101 extends to the rear of the moving contact, that is, in the direction of the rotating axis of the moving contact. The connecting portion 101 and the moving contact are connected to the same potential.

[0035] The equipotential moving arc-striking plate, the connecting part 101 is connected with the moving contact to form an equipotential, the guiding part 102 is located above the moving contact's opening limit position, the moving contact generates an arc when it is opened, and under the action of the current magnetic field of the moving arc-striking plate, the moving arc root of the arc is transferred to the guiding part and moves toward the arc burning part, thereby accelerating the movement of the arc toward the arc extinguishing chamber. The equipotential moving arc-striking plate is utilized to completely transfer the moving arc root of the moving contact's arc from the moving contact to the arc-striking plate, thereby avoiding the arc from ablating the moving contact material, and can greatly improve the circuit breaker's breaking capacity.

[0036] Example 1

[0037] An equipotential dynamic arc-starting plate comprises a connecting portion 101, a guiding portion 102 and an arc-burning portion 103.

[0038] The connection part 101 is connected to the moving contact with the same potential by a soft connection method, wherein one end of the soft wire 4 is connected to the connection part 101 and the other end of the soft wire is connected to the moving contact.

[0039] A connection area is provided on the connection part, and one end of the soft wire 4 is fixedly connected to the connection area of ​​the connection part by riveting, screw connection, crimping, or welding, and the other end of the soft wire 4 is fixedly connected to the moving contact 2 or the conductive part connected to the moving contact by riveting, screw connection, crimping, or welding.

[0040] In this embodiment, the connection area is a guide connection hole provided on the connection portion 101 .

[0041] See also Figure 2 The guide part 102 is a V-shaped structure, and the two ends of the V-shape of the guide part 102 are respectively connected to the connecting part 101 and the arc burning part 103. The guide part 102 is a V-shaped tip close to the moving contact side, which can effectively shorten the distance between the guide part and the moving contact in the open state, so that the moving arc root of the arc is quickly transferred to the guide part.

[0042] The arc burning portion 103 is arranged at the end of the arc extinguishing chamber, and fixing portions are arranged on both sides of the arc burning portion 103. The arc burning portion is connected to the insulating clamping plate 302 of the arc extinguishing chamber through the fixing portions, and a certain gap is retained between the arc burning portion 103 and the arc extinguishing grid at the uppermost end of the arc extinguishing chamber, and the end of the arc burning portion close to the guide portion does not exceed the end of the arc extinguishing grid.

[0043] The fixing part is a plug-in board arranged on both sides of the arc burning part, one end of the plug-in board is connected to the side end of the arc burning part, and the other end extends toward the guide part. An open groove is formed between the plug-in board and the arc burning part, and the opening of the open groove is located on the side of the arc burning part close to the guide part. When the arc is transferred to the arc burning part, the moving arc root is restricted from transferring to both sides of the arc burning part through the open groove. The plug-in board is connected to the sockets on the insulating clamping plates on both sides of the arc extinguishing chamber, so that the arc burning part is fixed on the top of the uppermost arc extinguishing grid and a certain gap is formed.

[0044] Example 2

[0045] The difference between this embodiment and embodiment 1 lies in the structure of the guide part. The other structures are the same and will not be described in detail. The structure of the guide part is as follows:

[0046] See also Figure 3 , an equipotential dynamic arc-starting plate, comprising a connecting portion 101, a guiding portion 102 and an arc-burning portion 103.

[0047] The guide portion is a flat plate structure. One end of the guide portion 102 is connected to the arcing portion, and the other end of the guide portion 102 is connected to the connecting portion. The connecting portion and the guide portion form an integral planar structure.

[0048] The equipotential dynamic arc-starting plate adopts an integrated molding process, which is a stamping process, a die-casting process, and an additive manufacturing process.

[0049] Example 3

[0050] The difference between this embodiment and embodiment 1 lies in the structure of the guide part. The other structures are the same and will not be described in detail. The structure of the guide part is as follows:

[0051] See also Figure 4 , an equipotential dynamic arc-starting plate, comprising a connecting portion 101, a guiding portion 102 and an arc-burning portion 103.

[0052] The guide portion 102 is a U-shaped structure, and the two ends of the U of the guide portion 102 are respectively connected to the connecting portion 101 and the arc burning portion 103. The guide portion 102 is a U-shaped closed side close to the moving contact, and the open end of the U is located at the top. The guide portion 102 is designed to be a U-shaped structure, so that the lower part of the guide portion 102 is close to the moving contact, shortening the distance between the guide portion and the moving contact in the open state, so that the moving arc root of the arc is quickly transferred to the guide portion.

[0053] Example 4

[0054] See also Figure 1 and 6 , an arc extinguishing system, including an arc extinguishing chamber 3, a moving contact 2, a static contact 6, a static arc-striking plate 6 and a moving arc-striking plate 1.

[0055] See also Figure 6 and7 The arc extinguishing chamber is located in the radial extension direction of the opening and closing movement trajectory of the moving contact, and the arc extinguishing chamber 3 is located between the moving arc striking plate 1 and the static arc striking plate 6, the static arc striking plate 6 and the static contact 5 are connected to the same potential, and the moving arc striking plate 1 and the moving contact are connected to the same potential through a soft wire 4.

[0056] See also Figure 5 The arc extinguishing chamber includes an arc extinguishing grid 301, an insulating clamping plate 302 and a gas outlet baffle 303.

[0057] Two insulating clamps are arranged in parallel and at intervals, and multiple arc extinguishing grids are fixed between the two insulating clamps from top to bottom. The air outlet baffle 303 is installed at the front end of the arc extinguishing grid (the end away from the moving contact), and the air outlet baffle 303 has multiple air outlet holes.

[0058] The arc burning part of the moving arc-starting plate 1 is plugged into the top of the two insulating clamping plates through a plug-in plate, and forms a gap of a certain distance with the uppermost arc-extinguishing grid, and the guiding part is located above the opening position of the moving contact.

[0059] The working principle of the arc extinguishing system is explained in detail below.

[0060] When the circuit breaker interrupts the fault current, the moving contact opens and rotates toward the moving arc-striking plate 1, and the moving contact separates from the static contact to generate an arc. The arc bends and moves toward the arc extinguishing chamber under the action of the airflow field and the magnetic field. When the arc contacts the guide portion of the moving arc-striking plate, the current is transferred from the moving contact to the soft-connected moving arc-striking plate, and then the moving arc root of the arc is transferred from the moving contact to the guide portion of the moving arc-striking plate. As the arc further moves toward the arc extinguishing chamber, the moving arc root of the arc moves toward the arc burning portion of the moving arc-striking plate under the action of the magnetic field and airflow field generated by the current on the moving arc-striking plate, thereby accelerating the movement of the arc toward the arc extinguishing chamber, which can effectively improve the current limiting capacity and breaking capacity of the circuit breaker, thereby avoiding the arc erosion of the moving contact material, and improving the breaking capacity and reliability of the circuit breaker. At the same time, this solution reduces the requirements for the anti-ablation of the moving contact material, and is easy to implement and low in cost.

[0061] Example 5

[0062] A circuit breaker comprises a circuit breaker body and an arc extinguishing system. The equipotential moving arc-starting plate is installed on the arc extinguishing system. The moving contact of the arc extinguishing system is connected to the operating structure inside the circuit breaker body, thereby driving the moving contact to open and close operations.

[0063] The above content is only for explaining the technical idea of ​​the utility model and cannot be used to limit the protection scope of the utility model. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the utility model shall fall within the protection scope of the claims of the utility model.

Claims

1. An equipotential moving arc-starting plate, characterized in that: The equipotential arc-starting plate comprises a connecting portion (101), a guiding portion (102) and an arc-burning portion (103); The arc burning portion (103) is arranged at the end of the arc extinguishing chamber, and there is a gap between the arc burning portion (103) and the arc extinguishing grid at the uppermost end of the arc extinguishing chamber; The guide part (102) is arranged on a side of the arc burning part (103) close to the moving contact and is located above the opening position of the moving contact, and is used to guide the moving arc root to the moving arc striking plate; The connecting portion (101) is connected to the guiding portion (102) and is located on one side of the moving contact; the end of the connecting portion (101) extends toward the rear of the moving contact; and the connecting portion (101) and the moving contact are connected to an equal potential.

2. The equipotential moving arc-starting plate according to claim 1, characterized in that: The guide portion is a flat plate structure, or a V-shaped or U-shaped structure extending toward the moving contact, and is used to shorten the distance between the guide portion and the moving contact so that the moving arc root is transferred to the guide portion.

3. The equipotential moving arc-starting plate according to claim 1, characterized in that: Insertion parts are arranged on both sides of the arc burning part, and the insertion parts are used for inserting and fixing with the insulating clamping plates of the arc extinguishing chamber.

4. The equipotential dynamic arc-starting plate according to claim 3, characterized in that: One end of the plug-in portion is connected to the side end of the arc burning portion, and the other end extends toward the guide portion, and an open groove is formed between the plug-in portion and the arc burning portion.

5. The equipotential moving arc-starting plate according to any one of claims 1 to 4, characterized in that: An end of the arc burning portion close to the guide portion does not exceed an end of the arc extinguishing grid.

6. The equipotential dynamic arc-starting plate according to claim 5, characterized in that: The connecting portion (101) is connected to the moving contact in a flexible connection manner to have an equal potential.

7. The equipotential moving arc-starting plate according to claim 6, characterized in that: The connecting part is provided with a connecting area, one end of the soft wire is connected to the connecting area, and the other end is connected to the moving contact (2) or to a conductive part connected to the moving contact.

8. An arc extinguishing system, characterized in that: It comprises an arc extinguishing chamber (3), a moving contact (2), a stationary contact (5), a stationary arc-starting plate (6) and the equipotential moving arc-starting plate according to any one of claims 1 to 7; The arc extinguishing chamber is located in the radial extension direction of the opening and closing movement trajectory of the moving contact, and the arc extinguishing chamber (3) is located between the moving arc striking plate (1) and the static arc striking plate (6), the static arc striking plate (6) and the static contact (5) are connected at the same potential, and the moving arc striking plate (1) and the moving contact are at the same potential.

9. An arc extinguishing system according to claim 8, characterized in that: The arc extinguishing chamber comprises an arc extinguishing grid (301), an insulating clamping plate (302) and a gas outlet baffle (303); Two insulating clamping plates are arranged in parallel and at intervals, and a plurality of arc extinguishing grids are fixed between the two insulating clamping plates at intervals from top to bottom. The gas outlet baffle (303) is installed at one end of the arc extinguishing grid away from the moving contact, and a plurality of gas outlet holes are opened on the gas outlet baffle (303).

10. A circuit breaker, characterized in that: The invention comprises a circuit breaker body and an arc extinguishing system, and the arc extinguishing system is installed with the equipotential moving arc-starting plate as described in any one of claims 1 to 7.

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