Arc extinguishing system and circuit breaker

Abstract

The arc extinguishing system comprises an arc extinguishing chamber assembly, a moving contact assembly and a static contact assembly, the arc extinguishing chamber assembly is installed at the upper end of the static contact assembly, and the moving contact assembly is located at the end, provided with an opening, of the arc extinguishing chamber assembly. Compared with the prior art, the arc extinguishing system has the advantages that the arc can be more easily guided into the arc extinguishing chamber to cut and extinguish the arc when the short-circuit current is cut off, so that the arc is basically not generated at the position of the main contact, and the burning loss of a conductive system is reduced.

Description

Technical Field

[0001] This invention relates to the field of circuit breaker technology, and more particularly to an arc extinguishing system and a circuit breaker. Background Technology

[0002] With the increasing global photovoltaic installations, the requirements for the size, breaking capacity, and rated operating voltage of DC circuit breakers are also becoming more stringent in various application scenarios. During the short-circuit current interruption process in DC systems, the lack of an inherent current zero-crossing point makes interrupting the DC short-circuit current (even a small multiple of the fault current) and extinguishing the arc difficult. When the moving and stationary contacts in the circuit breaker separate, an arc is generated. If the arc is not extinguished quickly, it may pose a safety hazard. Therefore, circuit breakers need to be equipped with reliable contact arc-extinguishing devices to quickly extinguish the arc and protect the circuit.

[0003] The arc-extinguishing system of a circuit breaker typically employs a single contact mechanism combined with multiple contact plates and a multi-layered stacked arc-extinguishing grid to extinguish the arc. To improve breaking capacity, multiple arc-extinguishing grids are usually combined to form a high stacking height. Furthermore, because the width formed by multiple moving contact plates connected in parallel is relatively wide, the arc-extinguishing grids also have a wide dimension in the width direction. This structure results in a weak magnetic field in the arc-trapping region, making it difficult for the arc to penetrate and cut through the grid. With the increase in operating voltage, the market places higher demands on the reliable breaking performance of circuit breakers, significantly increasing the difficulty of short-circuit breaking.

[0004] Existing technologies extinguish electric arcs by increasing the arc gap to lengthen the arc, by burning gas-generating materials to promote and cool the arc, and by enhancing the magnetic field to promote the arc. One method involves protruding at least one arc contact near the end of the moving contact body close to the arc-extinguishing unit. This ensures that during closing, the arc contact contacts the corresponding stationary contact earlier than other moving contacts, and during opening, the arc contact contacts separate later than other moving contacts. This guarantees that only the arc contact generates an arc during current interruption, while other moving contacts do not. Furthermore, the arc contact extends into an arc-extinguishing chamber with a narrow slit, lengthening the arc while simultaneously using the slit effect to compress the arc and burn the gas-generating material to extinguish it. However, as the breaking capacity increases, some high-temperature ionized gas overflows from the narrow slit, causing an arc between the moving and stationary contacts of adjacent phases, leading to current interruption failure.

[0005] In view of the aforementioned existing technology, it is necessary to make reasonable improvements to the structure of the existing contact arc extinguishing system. To this end, the applicant has made a beneficial design, and the technical solution described below is the result of this design.

[0006] Therefore, the present invention provides an arc extinguishing system that, when interrupting a short-circuit current, makes it easier for the arc to be guided into the arc extinguishing chamber for cutting and extinguishing, so that the main contact position is basically free of arc, thereby reducing the burn-out of the conductive system. Summary of the Invention

[0007] The purpose of this invention is to provide an arc extinguishing system and a circuit breaker, thereby solving the aforementioned problems existing in the prior art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An arc-extinguishing system includes: an arc-extinguishing chamber assembly, a moving contact assembly, and a stationary contact assembly, wherein the arc-extinguishing chamber assembly is mounted on the upper end of the stationary contact assembly, and the moving contact assembly is located at the end of the arc-extinguishing chamber assembly having an opening. The moving contact includes: multiple main contacts and an arc contact. The arc contact is located in the middle of the multiple main contacts, and the length of the arc contact is longer than the length of the main contacts. The multiple main contacts and the arc contact are fixed together by a fixed shaft. The main contacts are provided with a moving contact point, and the arc contact is provided with an arc contact point. The end of the arc contact near the arc-extinguishing chamber is provided with a first arc-starting angle. The arc-extinguishing chamber assembly includes: a first side plate, a second side plate, an arc-extinguishing chamber grid assembly, a first gas generating element, and a second gas generating element. The first gas generating element and the second gas generating element are symmetrically arranged, and there is a gap between the first gas generating element and the second gas generating element. The arc-extinguishing grid assembly is installed on the first gas generating element and the second gas generating element. The first side plate and the second side plate are respectively fixed to the outside of the first gas generating element and the second gas generating element. The stationary contact includes a stationary contact body. One end of the stationary contact body is provided with a detour portion, one end of which is connected to the stationary contact body. The other end of the detour portion extends away from the end connected to the stationary contact body. A first stationary contact point is also provided on the upper part of the detour portion. The detour portion is also connected to a connecting plate. The connecting plate is also provided with an arc-starting plate. A second stationary contact point is also provided on the upper part of the connection between the connecting plate and the arc-starting plate.

[0009] Furthermore, the arc-extinguishing grid assembly includes a first group of arc-extinguishing grids, a second group of arc-extinguishing grids, and a third group of arc-extinguishing grids. The first group of arc-extinguishing grids, the second group of arc-extinguishing grids, and the third group of arc-extinguishing grids are stacked sequentially from bottom to top. The width of the recess of the first group of arc-extinguishing grids is greater than the width of the recess of the second group of arc-extinguishing grids and the third group of arc-extinguishing grids. The recess of the second group of arc-extinguishing grids and the third group of arc-extinguishing grids form a narrow slit channel.

[0010] Furthermore, the arc contact extends into the recess, so that the arc contact point on the arc contact point corresponds to the second stationary contact point provided on the stationary contact point.

[0011] Furthermore, an insulating component is provided at one end of the stationary contact body near the moving contact.

[0012] Furthermore, a support member is provided between the stationary contact body and the connecting plate.

[0013] Furthermore, the arc-inducing plate is Z-shaped.

[0014] Furthermore, a pad is provided between the connecting plate and the arc-inducing plate, and the arc-inducing plate, the pad, and the connecting plate are fixed together by fixing screws.

[0015] Furthermore, the thickness of the first group of arc-extinguishing grids and the second group of arc-extinguishing grid sheets is greater than the thickness of the third group of arc-extinguishing grid sheets.

[0016] Furthermore, the upper end of the third set of arc-extinguishing grid plates is also provided with an arc-inducing plate, and the arc-inducing plate is also connected to a second arc-inducing angle, which extends in the direction of the second set of arc-extinguishing grid plates.

[0017] The present invention also includes a circuit breaker, wherein the circuit breaker gas includes the above-described arc extinguishing system.

[0018] The beneficial effects of this invention are: By extending the arc contact of the moving contact system into the arc-extinguishing chamber, the arc is ensured to quickly enter and extinguish after it is generated. In addition, the stationary contact of the arc-extinguishing system of the present invention has an increased arc-starting angle, and an arc-starting plate has also been added to the arc-extinguishing chamber. The arc-starting plate increases the arc-starting angle, which makes it easier for the arc to be guided into the arc-extinguishing chamber and cut off when the short-circuit current is interrupted, so that the main contact position is basically free of arc, reducing the burn-out of the conductive system and extending the service life of the product. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the arc extinguishing system of the present invention; Figure 2 This is a structural diagram of the arc-extinguishing chamber assembly of the present invention; Figure 3 This is a structural diagram of the arc-extinguishing chamber assembly of the present invention; Figure 4 This is a structural diagram of the moving contact assembly of the present invention; Figure 5 This is a structural diagram of the stationary contact assembly of the present invention; Figure 6 This is a diagram showing the tripping state of the moving contact assembly and the stationary contact assembly of the present invention; Figure 7 This is a diagram showing the closing state of the moving contact assembly and the stationary contact assembly of the present invention; Figure 8 This is an assembly diagram of the arc extinguishing system of the present invention.

[0020] Figure label: Arc extinguishing chamber assembly 1, moving contact assembly 2, stationary contact assembly 3, arc ignition plate 4; First side plate 11, second side plate 12, arc-extinguishing chamber grid assembly 13, first gas generating component 14, second gas generating component 15; Multiple main contacts 21, arc contacts 22, moving contacts 23, arc contacts 24, and first arc-leading angle 25; The first group of arc-extinguishing grid plates 131, the second group of arc-extinguishing grid plates 132, and the third group of arc-extinguishing grid plates 133; 31. Stationary contact body, 32. Detour section, 33. First stationary contact, 34. Connecting plate, 35. Arc-starting plate, 36. Second stationary contact, 37. Support member, 38. Pad plate; The second connection arc angle is 42°. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention or simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0025] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, components, and circuits well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0026] like Figures 1 to 8 As shown, an arc-extinguishing system includes: an arc-extinguishing chamber assembly 1, a moving contact assembly 2, and a stationary contact assembly 3. The arc-extinguishing chamber assembly 1 is mounted on the upper end of the stationary contact assembly 3, and the moving contact assembly 2 is located at the end of the arc-extinguishing chamber assembly 1 that has an opening. The moving contact 2 includes: multiple main contacts 21 and one arc contact 22. In this embodiment, the number of main contacts 21 is 8. However, in actual production, the number of main contacts 21 can be determined according to actual needs and is not limited. The arc contact 22 is located in the middle of the multiple main contacts 21, and the length of the arc contact 22 is longer than the length of the main contacts 21. The multiple main contacts 21 and the arc contact 22 are fixed together by a fixed shaft. The main contacts 21 are provided with moving contact points 23, and the arc contact 22 is provided with arc contact points 24. The end of the arc contact 22 near the arc-extinguishing chamber assembly is provided with a first arc-starting angle 25. The arc-extinguishing chamber assembly 1 includes: a first side plate 11, a second side plate 12, an arc-extinguishing chamber grid assembly 13, a first gas generating element 14, and a second gas generating element 15. The first side plate 11 and the second side plate 12 are of equal size and have the same structure. The first gas generating element 14 and the second gas generating element 15 are symmetrically arranged, and there is a gap between the first gas generating element 14 and the second gas generating element 15. One end of the arc-extinguishing grid assembly is installed on the first gas generating element 14 and the second gas generating element 15. In order to install the arc-extinguishing grid on the first gas generating element 14 and the second gas generating element 15, multiple grooves are sequentially opened from bottom to top on the first gas generating element 14 and the second gas generating element 15. During installation, the two edges of the arc-extinguishing grid are inserted into the grooves of the first gas generating element 14 and the second gas generating element 15. The first side plate 11 and the second side plate 13 are respectively fixed to the outside of the first gas generating element 14 and the second gas generating element 15 by fixing screws. In this embodiment, the arc-extinguishing grids of the arc-extinguishing grid assembly are staggered. The stationary contact assembly 3 includes a stationary contact body 31. One end of the stationary contact body 31 is provided with a detour portion 32, one end of which is connected to the stationary contact body 31. The other end of the detour portion 32 extends away from the end where it is connected to the stationary contact body 31. A first stationary contact point 33 is also provided on the upper part of the detour portion 32. The detour portion 32 is also connected to a connecting plate 34. The connecting plate 34 is also provided with an arc-starting plate 35. A second stationary contact point 36 is also provided on the upper part of the connection between the connecting plate 34 and the arc-starting plate 35. In this embodiment, the arc-starting plate 35 is Z-shaped. In actual production, the structure of the arc-starting plate 35 can also be other shapes, which are not limited to one by one.

[0027] As can be seen from the above, by extending the arc contact 22 of the moving contact system into the arc extinguishing chamber, it is ensured that the arc quickly enters the arc extinguishing chamber and is extinguished after it is generated. In addition, the stationary contact of the arc extinguishing system of the present invention is also increased to the arc-initiating plate 35, and the arc extinguishing chamber is also increased to the arc-initiating plate. The arc-initiating plate increases the arc-initiating angle. When the short-circuit current is interrupted, the arc can be more easily guided into the arc extinguishing chamber to be cut and extinguished, so that the main contact position basically does not generate an arc, reducing the burn-out of the conductive system and extending the service life of the product.

[0028] Furthermore, it is worth noting that the arc-extinguishing grid assembly 13 includes a first group of arc-extinguishing grids 131, a second group of arc-extinguishing grids 132, and a third group of arc-extinguishing grids 133. The first group of arc-extinguishing grids 131, the second group of arc-extinguishing grids 132, and the third group of arc-extinguishing grids 133 are stacked sequentially from bottom to top. The width of the recess in the first group of arc-extinguishing grids 131 is greater than the width of the recesses in the second group of arc-extinguishing grids 132 and the third group of arc-extinguishing grids 133. The recess of the third set of arc-extinguishing grid plates 133 forms a narrow slit channel. There is a gap between the arc-extinguishing grid plates. In this embodiment, the second set of arc-extinguishing grid plates 132 and the third set of arc-extinguishing grid plates 133 have the same shape and size. In addition, in order to be installed with the first side plate 11 and the second side plate 12, rivet members are provided on both sides of the arc-extinguishing grid plates. Rivet holes are also provided at the positions corresponding to the first side plate 11 and the second side plate 12. During installation, the rivet members are inserted into the rivet holes for fixing.

[0029] Furthermore, in order to quickly extinguish the generated arc in the arc-extinguishing chamber, the arc contact 22 extends into the recess, so that the arc contact 24 on the arc contact 22 corresponds to the second stationary contact 36 provided on the stationary contact. By extending the length of the arc contact 22 and extending it into the recess, it is ensured that the arc quickly enters the arc-extinguishing chamber and is extinguished after it is generated. The arc will burn between the arc contact and the stationary contact system, thereby reducing the burn-out of the main contact.

[0030] Additionally, it should be noted that an insulating component is provided at the end of the stationary contact body 21 near the moving contact. The insulating component can prevent the electric arc from moving backward. The insulating component is fixed to the end of the stationary contact body near the moving contact by an adhesive layer. In this embodiment, the insulating component is made of rubber. However, in actual production, the insulating component can also be made of other insulating materials, which are not limited here.

[0031] In order to prevent deformation of the stationary contact system and the moving contact system during opening and closing, in this embodiment, a support member 37 is provided between the stationary contact body and the connecting plate. The support member 37 can play a supporting role and prevent the force during opening and closing from affecting the deformation of the stationary contact.

[0032] Additionally, it should be noted that a pad 38 is provided between the connecting plate 34 and the arc-starting plate 35. The pad 38 can raise the height of the arc-starting plate 34, ensuring that the arc-starting plate 34 is installed in a suitable position, which is beneficial to the arc-starting effect. In order to firmly fix the arc-starting plate, the pad, and the connecting plate, in this embodiment, the arc-starting plate 35, the pad 38, and the connecting plate 34 are fixed together by fixing screws.

[0033] In addition, it is worth mentioning that the thickness of the first group of arc-extinguishing grids 131 and the second group of arc-extinguishing grids 132 is greater than the thickness of the third group of arc-extinguishing grids 133. Since the arc-extinguishing grids of the first group of arc-extinguishing grids 131 and the second group of arc-extinguishing grids 132 are relatively thick, it is to prevent the arc generated when the stationary contact system and the moving contact system are opening from breaking through the arc-extinguishing grids. In addition, since the arc generated during opening moves from bottom to top and the arc gradually weakens, the thickness of the third group of arc-extinguishing grids 133 can be reduced, thereby saving costs. In addition, the upper end of the third set of arc-extinguishing grid plates 133 is also provided with an arc-inducing plate 4. The arc-inducing plate 4 is also connected to a second arc-inducing angle 42. The second arc-inducing angle 42 extends in the direction of the second set of arc-extinguishing grid plates 132. The arc is more easily introduced into the arc-extinguishing chamber and extinguished by the second arc-inducing angle 42.

[0034] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An arc-extinguishing system, characterized in that, It includes: an arc-extinguishing chamber assembly, a moving contact assembly, and a stationary contact assembly. The arc-extinguishing chamber assembly is mounted on the upper end of the stationary contact assembly, and the moving contact assembly is located at the open end of the arc-extinguishing chamber assembly. The moving contact includes: multiple main contacts and an arc contact. The arc contact is located in the middle of the multiple main contacts, and the length of the arc contact is longer than the length of the main contacts. The multiple main contacts and the arc contact are fixed together by a fixed shaft. The main contacts are provided with a moving contact point, and the arc contact is provided with an arc contact point. The end of the arc contact near the arc-extinguishing chamber is provided with a first arc-starting angle. The arc-extinguishing chamber assembly includes: a first side plate, a second side plate, an arc-extinguishing chamber grid assembly, a first gas generating element, and a second gas generating element. The first gas generating element and the second gas generating element are symmetrically arranged, and there is a gap between the first gas generating element and the second gas generating element. The arc-extinguishing grid assembly is installed on the first gas generating element and the second gas generating element. The first side plate and the second side plate are respectively fixed to the outside of the first gas generating element and the second gas generating element. The stationary contact includes a stationary contact body. One end of the stationary contact body is provided with a detour portion, one end of which is connected to the stationary contact body. The other end of the detour portion extends away from the end connected to the stationary contact body. A first stationary contact point is also provided on the upper part of the detour portion. The detour portion is also connected to a connecting plate. The connecting plate is also provided with an arc-starting plate. A second stationary contact point is also provided on the upper part of the connection between the connecting plate and the arc-starting plate.

2. The arc-extinguishing system according to claim 1, characterized in that: The arc-extinguishing grid assembly includes a first group of arc-extinguishing grids, a second group of arc-extinguishing grids, and a third group of arc-extinguishing grids. The first group of arc-extinguishing grids, the second group of arc-extinguishing grids, and the third group of arc-extinguishing grids are stacked sequentially from bottom to top. The width of the recess of the first group of arc-extinguishing grids is greater than the width of the recess of the second group of arc-extinguishing grids and the third group of arc-extinguishing grids. The recess of the second group of arc-extinguishing grids and the third group of arc-extinguishing grids form a narrow slit channel.

3. The arc-extinguishing system according to claim 1, characterized in that: The arc contact extends into the recess, so that the arc contact point on the arc contact point corresponds to the second stationary contact point provided on the stationary contact point.

4. The arc-extinguishing system according to claim 1, characterized in that: An insulating component is also provided at one end of the stationary contact body near the moving contact.

5. The arc-extinguishing system according to claim 1, characterized in that: A support member is also provided between the stationary contact body and the connecting plate.

6. The arc-extinguishing system according to claim 1, characterized in that: The arc-starting plate is Z-shaped.

7. The arc extinguishing system according to claim 1, characterized in that: A pad is also provided between the connecting plate and the arc-inducing plate. The arc-inducing plate, the pad, and the connecting plate are fixed together by fixing screws.

8. The arc-extinguishing system according to claim 1, characterized in that: The thickness of the first group of arc-extinguishing grids and the second group of arc-extinguishing grid sheets is greater than the thickness of the third group of arc-extinguishing grid sheets.

9. The arc-extinguishing system according to claim 8, characterized in that: The upper end of the third set of arc-extinguishing grid plates is also provided with an arc-inducing plate, and the arc-inducing plate is also connected to a second arc-inducing angle, which extends in the direction of the second set of arc-extinguishing grid plates.

10. A circuit breaker, comprising an arc-extinguishing system, characterized in that, The arc extinguishing system is the same as that described in any one of claims 1 to 9.

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