circuit breaker

Abstract

A circuit breaker includes a housing, an operating mechanism, and at least one switching unit disposed within the housing. The switching unit includes a contact mechanism, which includes a contact cover rotatably mounted on a contact support. The contact cover has one of a guide protrusion and a guide groove. The housing contains the other of a guide protrusion and a guide groove. The guide protrusion is slidably inserted into the guide groove. The contact support can drive the guide protrusion to slide along the guide groove. The guide protrusion and guide groove drive the contact cover to rotate relative to the contact support. When the moving contact and the stationary contact separate, the contact cover rotates to the position between the moving and stationary contacts. When the moving and stationary contacts contact, the contact cover moves away from the position between the moving and stationary contacts. The contact cover can move into position and block the moving and stationary contacts before the contact support moves to the fully open position.

Description

Technical Field

[0001] This invention relates to the field of low-voltage electrical appliances, and more specifically to a circuit breaker. Background Technology

[0002] Low-voltage circuit breakers and circuit breakers are the most important electrical equipment in power distribution systems and new energy systems. With the continuous increase in system voltage, the performance requirements for circuit protection switches are also getting higher and higher. Miniaturization, high performance, modularization, and high reliability are the main development directions of air circuit breakers and circuit breakers at present.

[0003] With the development of electricity, the operating voltage of power systems has been continuously increasing, with AC voltage reaching up to 1500V and DC voltage increasing to 2500V. However, because DC systems do not have a natural zero-crossing point compared to AC systems, they cannot extinguish the arc instantly at the zero-crossing point of AC current. Instead, they rely on rapidly elongating and cooling the arc to quickly increase the arc voltage and extinguish it as soon as possible. Therefore, extinguishing the arc is more difficult, and the requirements for the arc-extinguishing mechanism are becoming increasingly stringent, which existing arc-extinguishing systems struggle to meet. Although a contact cover can be installed between the moving and stationary contacts, moving between them during opening to prevent arc root formation at the moving contact and accelerate arc extinguishing, most existing contact covers rely on gravity, elastic reset elements, or linkage transmission, resulting in slow movement speeds and an inability to quickly cover the moving contact. Summary of the Invention

[0004] The purpose of this invention is to overcome at least one defect of the prior art and provide a circuit breaker.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A circuit breaker includes a housing, an operating mechanism, and at least one switching unit disposed within the housing. The switching unit includes a contact mechanism and an arc-extinguishing mechanism. The contact mechanism includes a moving contact, a stationary contact, and a contact support. The moving contact is disposed on the contact support. The operating mechanism can drive the contact support to rotate, thereby causing the moving contact to contact and separate from the stationary contact via the contact support.

[0007] The contact mechanism further includes a contact cover rotatably mounted on a contact support. The contact cover includes two opposing rotating parts and a shielding part connected between the two rotating parts. The two rotating parts are oppositely mounted on both sides of the contact support and are rotatably connected to the contact support respectively.

[0008] The rotating part is provided with one of a guide protrusion and a guide groove at an eccentric position, and the housing is provided with the other of a guide protrusion and a guide groove. The guide protrusion slides into the guide groove.

[0009] The contact support can drive the guide protrusion to slide along the guide groove. The guide protrusion and guide groove drive the contact cover to rotate relative to the contact support. When the moving contact and the stationary contact separate, the contact cover rotates to the space between the moving contact and the stationary contact. When the moving contact and the stationary contact come into contact, the contact cover moves away from the space between the moving contact and the stationary contact.

[0010] Preferably, the stationary contact includes a first stationary contact portion, and the moving contact includes a first moving contact portion corresponding to the first stationary contact portion.

[0011] When the first stationary contact part separates from the first moving contact part, the contact cover rotates at least to between the first stationary contact part and the first moving contact part. When the first stationary contact part and the first moving contact part come into contact, the contact cover moves away from between the first stationary contact part and the first moving contact part.

[0012] Preferably, the housing is provided with two opposing partitions for each switch unit, the switch unit is disposed between the two partitions, the two partitions are respectively provided with two rotating parts of the contact cover, the two partitions are respectively provided with guide grooves, and the two rotating parts are provided with guide protrusions.

[0013] Preferably, the contact support includes two support plates rotatably connected to the housing, and a support seat disposed between the two support plates. The moving contact is rotatably disposed on the support seat, and a contact spring is provided between the moving contact and the support seat. Two rotating parts of the contact cover are disposed on the outer side of the two support plates. The ends of the two rotating parts away from the stationary contact are rotatably connected to the support plates through rotating shafts, and the ends of the two rotating parts near the stationary contact are provided with guide protrusions.

[0014] Preferably, the housing includes a base plate and a base. The base plate has a first isolation portion, and the base has a second isolation portion corresponding to the first isolation portion. The first isolation portion and the second isolation portion are used to form a partition. The first isolation portion has a first guide structure with a first guide surface. The second isolation portion has a second guide structure corresponding to the first guide structure with a second guide surface. The first isolation portion and the second isolation portion form a partition after the base plate and the base are assembled. The first guide structure and the second guide structure are spaced apart and the first guide surface and the second guide surface are arranged opposite to each other, forming a guide groove between the first guide surface and the second guide surface.

[0015] Preferably, the first guide surface includes a first pushing segment and a first limiting segment connected together, and the second guide surface includes a second pushing segment and a second limiting segment connected together. The first pushing segment and the second pushing segment are disposed opposite to each other, and the guide groove is formed between the first pushing segment and the second pushing segment.

[0016] As the moving contact moves closer to the stationary contact, the first pushing section pushes the guide protrusion, causing the contact cover to rotate away from the moving contact.

[0017] When the first stationary contact part comes into contact with the first moving contact part, the guide protrusion slides to the side limit of the first limiting section, limiting the contact cover to a position away from the moving contact.

[0018] When the moving contact moves away from the stationary contact, the second pushing section pushes the guide protrusion, causing the contact cover to rotate in the direction between the first moving contact and the first stationary contact.

[0019] When the contact cover rotates to the position between the first moving contact and the first stationary contact, the guide protrusion slides to the side limit of the second limiting section, thus limiting the contact cover between the first moving contact and the first stationary contact.

[0020] Preferably, the stationary contact further includes a second stationary contact portion located in the arc extinguishing mechanism, and the moving contact further includes a second moving contact portion corresponding to the second stationary contact portion. The distance from the second moving contact portion to the contact support rotation center is greater than the distance from the first moving contact portion to the contact support rotation center. The second moving contact portion can contact the second stationary contact portion before the first moving contact portion contacts the first stationary contact portion, and the second moving contact portion can separate from the second stationary contact portion after the first moving contact portion separates from the first stationary contact portion.

[0021] Preferably, two isolation structures are provided between the arc extinguishing mechanism and the contact mechanism. The two isolation structures are spaced apart, and an arc-inducing channel is formed between the two isolation structures to avoid the second moving contact. The second moving contact passes through the arc-inducing channel and contacts the second stationary contact.

[0022] The arc extinguishing mechanism includes multiple arc extinguishing grids. Each arc extinguishing grid has an arc extinguishing notch on its side near the contact mechanism. Each arc extinguishing grid has an arc extinguishing support on both sides of the arc extinguishing notch. One isolation structure is connected to one support on one side of the multiple arc extinguishing grids, and the other isolation structure is connected to the other support on the other side of the multiple arc extinguishing grids. The isolation structure includes an isolation cover and an isolation platform. The isolation covers of the two isolation structures are respectively fitted onto the arc extinguishing supports on both sides of the arc extinguishing grids. Multiple isolation plates for insertion between two adjacent arc extinguishing grids are provided inside the isolation cover. The isolation platforms of the two isolation structures are arranged facing each other, forming an arc-initiating channel between the two isolation platforms.

[0023] Preferably, the wiring mechanism includes a connection to a stationary contact. The wiring mechanism includes a conductive element and a first connector and a second connector disposed opposite to each other on both sides of the conductive element. The conductive element has a first stationary contact portion. The first connector is connected between the conductive element and the housing. The second connector is connected between the conductive element and the housing. The second connector has a second stationary contact portion and an upper connector portion extending into the arc extinguishing mechanism.

[0024] Preferably, the shielding part includes a first shielding part with a planar shape and a second shielding part with an arc shape. The second shielding part is located on the side of the first shielding part closer to the arc extinguishing mechanism. The end of the rotating part connected to the shielding part is fan-shaped. The end of the rotating part away from the shielding part is rotatably connected to the contact via a rotating shaft. The guide protrusion on the rotating part is located at the end closer to the shielding part.

[0025] In this embodiment of the circuit breaker, when the contact support rotates, it drives the guide protrusion to slide along the guide groove, thereby enabling the contact cover to quickly cover the silver point and prevent back-side breakdown. It does not require lengthening the opening distance to improve arc extinguishing performance, and has the characteristics of small size. Moreover, it does not require gravity or spring to drive the contact cover to rotate, which allows the contact cover to rotate more quickly. Before the contact support moves to the fully open position, the contact cover can move into place and block between the moving contact and the stationary contact.

[0026] In addition, by assembling the base plate and the base to form a guide groove, the assembly difficulty can be reduced. The contact support can be directly assembled onto the base. The guide protrusion can be located on one side of the first guide structure. Then, the second guide structure is aligned with the first guide structure, and the base plate is assembled onto the base to form a guide groove and cooperate with the guide protrusion. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the circuit breaker created by the present invention;

[0028] Figure 2 This is a schematic diagram of the structure after the hidden base is created according to the present invention;

[0029] Figure 3 This is a cross-sectional view of the circuit breaker invented in this invention;

[0030] Figure 4 This is a schematic diagram of the contact mechanism created in this invention;

[0031] Figure 5 This is a schematic diagram of the structure of the base plate of this invention;

[0032] Figure 6 This is a schematic diagram of the structure of the base of the present invention;

[0033] Figure 7This is a schematic diagram of the structure of the circuit breaker when it is in the tripped position according to the present invention;

[0034] Figure 8 This is a schematic diagram of the structure of the circuit breaker when it starts to close, as described in this invention.

[0035] Figure 9 This is a schematic diagram of the structure of the circuit breaker when it is in the closed position as described in this invention;

[0036] Figure 10 This is a schematic diagram of the structure of the circuit breaker when it begins to trip, as described in this invention.

[0037] Figure 11 This is a schematic diagram of the circuit breaker tripping process created by the present invention;

[0038] Figure 12 This is a top view of the arc-extinguishing mechanism created by the present invention;

[0039] Figure 13 This is a schematic diagram of the arc-extinguishing mechanism created in this invention;

[0040] In the picture:

[0041] 1 Switching unit 51 Rotating part

[0042] 2 Contact mechanism 52 Blocking part

[0043] 3 Arc-extinguishing mechanism 53 rotating shaft

[0044] 4 Wiring Mechanism 71 First Guide Structure

[0045] 5. Contact cover 72. First guide surface

[0046] 6 guide protrusions 73 second guide structure

[0047] 7 guide groove 74 second guide surface

[0048] 8. Isolation structure 81. Isolation enclosure

[0049] 11 base plate 82 isolation table

[0050] 12 base 231 support plate

[0051] 13 First Isolation Section 232 Support Seat

[0052] 14 Second Isolation Section 421 First Connecting Section

[0053] 21 First moving contact part 422 Second connecting part

[0054] 22 First static contact part 424 Lower connecting part

[0055] 23-contact support 425 upper connection part

[0056] 24 Second static contact part 426 Middle connecting part

[0057] 25 Second moving contact part 521 First shielding part

[0058] 31 Mounting base 522 Second shielding part

[0059] 32 Mounting Plate 721 First Push Section

[0060] 33 Arc-extinguishing grid plate 723 First limiting section

[0061] 34 Arc-extinguishing gap 741 Second thrust segment

[0062] 35 Arc-extinguishing support leg 742 Second transition section

[0063] 41 First connector 743 Second limiting segment

[0064] 42 Second connector Detailed Implementation

[0065] The following embodiments, in conjunction with the accompanying drawings, further illustrate specific implementations of the circuit breaker created by the present invention. The circuit breaker created by the present invention is not limited to the descriptions of the following embodiments.

[0066] like Figure 1-2 As shown, the circuit breaker in this embodiment includes a housing and an operating mechanism (not shown), a protection mechanism, a drive mechanism, and at least one switching unit 1 respectively disposed in the housing. The housing includes a base plate 11 and a base 12 mounted opposite to the base plate 11. The operating mechanism and at least one switching unit 1 are arranged side by side along the width direction of the circuit breaker. The switching unit 1 includes a contact mechanism 2, an arc extinguishing mechanism 3, and two wiring mechanisms 4. The contact mechanism 2 includes a moving contact, a stationary contact, and a contact support 23. The moving contact is disposed on the contact support 23. The moving contact and the stationary contact are respectively connected to the line through the corresponding wiring mechanism 4. The contact support 23 can drive the moving contact to contact and separate from the stationary contact to respectively connect and disconnect the connected line.

[0067] A main shaft is provided on one side of the operating mechanism. The operating mechanism is connected to the contact support 23 through the main shaft. A cantilever is provided on the main shaft to drive the contact support 23 to rotate. Under the drive of the drive mechanism, the operating mechanism drives all the contact supports 23 of the switch unit 1 to rotate through the main shaft, so that the contact support 23 drives the moving contact to contact and separate from the stationary contact. The drive mechanism can be a manually operated handle or an electric motor.

[0068] The protection mechanism is used to unlock the operating mechanism when a line fault occurs, causing the operating mechanism to trip and release the tripping spring. The tripping spring drives the contact support 23 to separate the moving contact from the stationary contact, thereby disconnecting the line and achieving the protection function. The arc extinguishing mechanism 3 is used to extinguish the arc generated by the contact system. The protection mechanism typically includes an overload protection mechanism and a short-circuit protection mechanism. In this embodiment, the circuit breaker's protection mechanism is an intelligent protection mechanism, which has both overload and short-circuit protection functions.

[0069] One improvement in this embodiment is that, Figure 2-6 As shown, the contact mechanism 2 further includes a contact cover 5 rotatably mounted on the contact support 23. The contact cover 5 includes two opposing rotating parts 51 and a shielding part 52 connected between the two rotating parts 51. The two rotating parts 51 are oppositely mounted on both sides of the contact support 23 and are rotatably connected to the contact support 23 respectively. One of a guide protrusion 6 and a guide groove 7 is provided at an off-center position of the rotating part 51. The other of the guide protrusion 6 and the guide groove 7 is provided inside the housing. The guide protrusion 6 is slidably inserted into the guide groove 7. The contact support 23 can drive the guide protrusion 6 to slide along the guide groove 7. The guide protrusion 6 and the guide groove 7 drive the contact cover 5 to rotate relative to the contact support 23. When the moving contact and the stationary contact separate, the contact cover 5 rotates to the position between the moving contact and the stationary contact. When the moving contact and the stationary contact contact, the contact cover 5 moves away from the position between the moving contact and the stationary contact. The off-center position of the rotating part 51 refers to the position that is off-center from the rotation center of the rotating part 51.

[0070] In this embodiment of the circuit breaker, when the contact support 23 rotates, it drives the guide protrusion 6 to slide along the guide groove 7. The guide protrusion 6 drives the contact cover 5 to rotate and quickly cover the silver point, preventing back-side breakdown. It does not need to improve arc extinguishing performance by lengthening the opening distance, and has the characteristics of small size. Moreover, it does not need to use gravity or spring to drive the contact cover to rotate, which allows the contact cover 5 to rotate more quickly. Before the contact support 23 moves to the fully open position, the contact cover 5 can move into position and block between the moving contact and the stationary contact.

[0071] like Figure 4As shown, the contact support 23 includes two support plates 231 rotatably connected to the housing, and a support seat 232 disposed between the two support plates 231. The moving contact is rotatably disposed on the support seat 232. A contact spring is provided between the moving contact and the support seat 232. The contact spring pre-tightens the moving contact on the contact support 23 to provide overtravel and increase the contact force between the moving contact and the stationary contact. Two rotating parts 51 of the contact cover 5 are disposed on the outside of the two support plates 231. The ends of the two rotating parts 51 away from the stationary contact are rotatably connected to the support plates 231 through rotating shafts 53. The ends of the two rotating parts 51 near the stationary contact are provided with guide protrusions 6. The housing is provided with two opposing partitions corresponding to the switch unit 1. The contact mechanism 2, the arc extinguishing mechanism 3, and the two wiring mechanisms 4 of the switch unit 1 are all disposed between the two partitions. The two partitions are respectively disposed corresponding to the two rotating parts 51 of the contact cover 5. Guide grooves 7 are provided on the two partitions respectively. The guide grooves 7 push the guide protrusions 6 to drive the contact cover 5 to rotate. Alternatively, guide protrusions 6 can be provided on the two partitions respectively, and guide grooves 7 can be provided on the two rotating parts 51 of the contact cover 5 respectively. The guide protrusions 6 can push the guide grooves 7 to drive the contact cover 5 to rotate. It is also possible. It can be understood that the side wall of the housing is also one of the partitions. When only one switch unit 1 is provided in the housing, the side walls on both sides of the housing serve as two partitions, and guide grooves 7 or guide protrusions 6 are provided. It should be noted that it is a preferred embodiment to provide guide grooves 7 or guide protrusions 6 on the partitions. Only the existing partitions need to be improved, and no new structure needs to be added. Of course, guide grooves 7 or guide protrusions 6 can also be provided on other parts of the housing. For example, a corresponding fixing post can be provided in the housing, and the guide grooves 7 or guide protrusions 6 shown are provided on the fixing post.

[0072] As shown in Figures 5-7, the bottom plate 11 of the housing is provided with a first isolation portion 13, and the base 12 is provided with a second isolation portion 14 corresponding to the first isolation portion 13. The first isolation portion 13 and the second isolation portion 14 are used to form a partition. The first isolation portion 13 is provided with a first guide structure 71, and a first guide surface 72 is provided on the first guide structure 71. The second isolation portion 14 is provided with a second guide structure 73 corresponding to the first guide structure 71, and a second guide surface 74 is provided on the second guide structure 73. After the bottom plate 11 and the base 12 are assembled, the first isolation portion 13 and the second isolation portion 14 form a partition. The plate has a first guide structure 71 and a second guide structure 73 spaced apart, with the first guide surface 72 and the second guide surface 74 facing each other. A guide groove 7 is formed between the first guide surface 72 and the second guide surface 74. The guide groove 7 is formed by assembling the base plate 11 and the base 12, which can reduce the assembly difficulty. The contact support 23 can be directly assembled onto the base 12. The guide protrusion 6 is located on one side of the second guide structure 73. Then, the first guide structure 71 and the second guide structure 73 are aligned, and the base plate 11 is assembled onto the base 12. The first guide structure 71 presses on the guide protrusion 6 to achieve the fit.

[0073] Furthermore, such as Figure 7 As shown, the first guide surface 72 includes a first pushing section 721 and a first limiting section 723, and the second guide surface 74 includes a second pushing section 741 and a second limiting section 743, as well as a second transition section 742 connecting the second pushing section 741 and the second limiting section 743. The first pushing section 721 and the second pushing section 741 are arranged opposite to each other, and both the first pushing section 721 and the second pushing section 741 are inclined to the length direction of the circuit breaker. The guide groove 7 is formed between the first pushing section 721 and the second pushing section 741. The guide protrusion 6 is cylindrical. The distance between the first pushing section 721 and the second pushing section 741 is greater than the diameter of the guide protrusion 6. The end of the first pushing section 721 away from the first limiting section 723 is set higher than the second limiting section 743, and the end of the second pushing section 741 away from the second limiting section 743 is set higher than the first limiting section 723. It is understood that the first pushing section 721 and the second pushing section 741 can also be arranged parallel to the length direction of the circuit breaker, and both fall within the protection scope of this invention.

[0074] refer to Figure 1 As shown, in this embodiment, the circuit breaker has mutually perpendicular height, width, and length directions, so as to... Figure 7 For example, Figure 7 The vertical direction represents the length of the circuit breaker, and the horizontal direction represents its height. (The last two characters appear to be incomplete and cannot be translated.) Figure 7 The orientation of the paper is the width direction of the circuit breaker.

[0075] like Figure 8As shown, the force F1 applied to the guide protrusion 6 by the first pushing section 721 passes through the rotating part 51 and points downwards from the center of rotation. The angle φ2 between the direction of the force F1 and the line connecting the guide protrusion 6 to the center of rotation of the rotating part 51 is an acute angle to ensure that the contact cover 5 rotates counterclockwise. The second limiting section 743 is a plane parallel to the height direction of the circuit breaker, and the second transition section 742 is an arc surface, serving a transition function.

[0076] like Figure 10 As shown, the direction of the force F2 applied by the second pushing section 741 to the guide protrusion 6 passes above the rotation center of the rotating part 51, and the angle φ1 between the direction of the force F2 and the line connecting the guide protrusion 6 to the rotation center of the rotating part 51 is an obtuse angle, so as to ensure that the contact cover 5 rotates clockwise.

[0077] It is understandable that a complete guide groove 7 could be provided on the base 12, with an entrance for inserting the guide protrusion 6. The guide protrusion 6 would be inserted into the guide groove 7 during assembly, but this would increase the assembly difficulty of the contact support 23. Furthermore, when the guide protrusion 6 is provided on the partition, the first guide structure 71 and the second guide structure 73 together form the guide protrusion 6, or the guide protrusion 6 can be provided only on the first isolation portion 13 of the base plate 11 or the second isolation portion 14 of the base 12. Additionally, the guide protrusion 6 can also take other shapes.

[0078] like Figure 4 As shown, the shielding part 52 includes a planar first shielding part 521 and an arc-shaped second shielding part 522. The second shielding part 522 is located on the side of the first shielding part 521 near the arc extinguishing mechanism 3. The end of the rotating part 51 connected to the shielding part 52 is fan-shaped. The end of the rotating part 51 away from the shielding part 52 is rotatably connected to the contact support 23 through a rotating shaft 53. The guide protrusion 6 on the rotating part 51 is located near the end of the shielding part 52. The arc-shaped second shielding part 522 can move faster than the planar first shielding part 521 to the space between the first moving contact part 21 and the first stationary contact part 22 when the contact cover 5 just starts to rotate, which can improve the arc extinguishing effect.

[0079] like Figure 3-4As shown, the stationary contact includes a first stationary contact portion 22 located outside the arc-extinguishing mechanism 3 and a second stationary contact portion 24 located within the arc-extinguishing mechanism 3. The moving contact includes a first moving contact portion 21 corresponding to the first stationary contact portion 22 and a second moving contact portion 25 corresponding to the second stationary contact portion 24. The distance from the second moving contact portion 25 to the rotation center of the contact support 23 is greater than the distance from the first moving contact portion 21 to the rotation center of the contact support 23. When the circuit breaker is closed, the second moving contact portion 25 can contact the second stationary contact portion 24 before the first moving contact portion 21 contacts the first stationary contact portion 22. After the first moving contact portion 21 contacts the first stationary contact portion 22, the second moving contact portion 25 can separate from the second stationary contact portion 24. When the circuit breaker is opened, the second moving contact portion 25 separates from the second stationary contact portion 24 after the first moving contact portion 21 separates from the first stationary contact portion 22, and pulls the arc toward the arc-extinguishing mechanism 3. The first moving contact 21 and the first stationary contact 22 are mainly responsible for carrying current, while the second moving contact 25 and the second stationary contact 24 play the role of arc initiation and protect the first moving contact 21 and the first stationary contact 22, reducing the burning of the first moving contact 21 and the first stationary contact 22 by the electric arc.

[0080] In this embodiment, the contact cover 5 is mainly used to protect the first stationary contact 22 and the first moving contact 21. This allows the contact cover 5 to rotate at a smaller angle and at a faster speed. When the first stationary contact 22 and the first moving contact 21 separate, the contact cover 5 rotates at least to between the two parts. When the first stationary contact 22 and the first moving contact 21 come into contact, the contact cover 5 moves away from between them. Alternatively, the shielding portion 52 of the contact cover 5 can be made larger to isolate more of the moving and stationary contacts, including isolating the second moving contact 25 and the second stationary contact 24. However, this would slow down the rotation and increase the space required.

[0081] In this embodiment, the contact support 23 has 12 conductive plates 20, each conductive plate 20 having a first moving contact portion 21. The three conductive plates 20 located in the middle each have a second moving contact portion 25 extending into the arc-extinguishing mechanism 3. When the first moving contact portion 21 contacts and separates from the first stationary contact portion 22, it simultaneously drives the three second moving contact portions 25 to contact and separate from the second stationary contact portion 24. Of course, the number of second moving contact portions 25 can be one, two, or more, and the number of first moving contact portions 21 can also be adjusted; all of these fall within the scope of protection of this invention. It should also be noted that, as in other conventional embodiments, the moving contact may not have second moving contact portions 25, only first moving contact portions 21, and the corresponding stationary contact may not have second stationary contact portions 24.

[0082] like Figure 12As shown, when the circuit breaker interrupts a high-current arc, the high-temperature charged plasma in the arc column region will be ejected in the direction of the arrow, forming an arc-splitting trajectory. If the contact cover 5 does not shield the first moving contact 21, the arc splitting will cause electrical breakdown between the second stationary contact 24 and the first moving contact 21 due to the high temperature and high voltage, and replace the main arc. Even worse, breakdown may occur between the first stationary contact 22 and the first moving contact 21, resulting in interruption failure. By using the contact cover 5 to cover the first moving contact 21 during the opening process, rapid shielding is achieved during the arc initiation stage, which can effectively prevent electrical breakdown between the stationary contact and the first moving contact 21.

[0083] like Figure 7-8 As shown, the circuit breaker is composed of Figure 7 The circuit breaker is shown in the open position. The closing operation begins and the circuit breaker moves to the indicated position. Figure 8 At the position shown, the contact support 23 drives the moving contact to move closer to the stationary contact. The guide protrusion 6 slides into the guide groove 7 from the position limited by the second limiting section 743. The first pushing section 721 pushes the guide protrusion 6, causing the contact cover 5 to rotate away from the moving contact, fully exposing the first moving contact 21 and making way for the stationary contact. The direction of force on the guide protrusion 6 is as shown by the arrow. At this time, the first stationary contact 22 and the first moving contact 21 have not yet made contact. The contact support 23 can continue to rotate and drive the second moving contact 25 to make contact with the second stationary contact 24 first.

[0084] like Figure 9 As shown, the contact support 23 continues to rotate and drives the first stationary contact 22 to contact the first moving contact 2. The guide protrusion 6 slides to the side limit of the first limiting section 723, limiting the contact cover 5 to a position away from the moving contact. Since the first stationary contact 22 and the first moving contact 21 contact and compress the contact spring in the contact support 23, it will also support the second moving contact 25 and the second stationary contact 24 to open a certain gap, ensuring that the first stationary contact 22 and the first moving contact 21 are in reliable contact.

[0085] like Figure 10 As shown, by Figure 9 During the opening process from the closed state, the first stationary contact 22 and the first moving contact 21 separate first. Under the action of the contact spring, the second moving contact 25 resets and contacts the second stationary contact 24. At this time, the direction of force on the guide protrusion 6 transmission part is as shown by the arrow. The second pushing section 741 pushes the guide protrusion 6, causing the contact cover 5 to rotate clockwise in the direction between the first moving contact 21 and the first stationary contact 22. Preferably, the first limiting section 723 is an arc surface, which is conducive to the guide protrusion 6 quickly switching to the second pushing section 741 when opening.

[0086] like Figure 11As shown, the second stationary contact 24 and the second moving contact 25 have also separated. The contact cover 5 moves between the first moving contact 21 and the first stationary contact 22 and completely covers the surface of the first moving contact 21. The guide protrusion 6 is still in sliding engagement with the second push section 741. At this time, the contact support 23 has not yet fully opened to the open position. At this time, the opening distance D2 is less than or equal to 0.5 times the maximum opening distance D1. This scheme can achieve the effect of quickly covering the first moving contact 21, and can effectively prevent the occurrence of back-side breakdown during the arc initiation stage. In particular, it can achieve the effect of completely blocking the first moving contact 21 when the moving contact moves to 50% of the farthest distance of the stationary contact.

[0087] Contact support 23 continues to rotate to Figure 7 At the indicated position, the circuit breaker is in the tripped position, meaning the first moving contact 21 and the first stationary contact 22 are separated to their maximum distance. Simultaneously, the guide protrusion 6 slides to the side limit of the second limiting section 743, limiting the contact cover 5 between the first moving contact 21 and the first stationary contact 22.

[0088] like Figure 12-13 As shown, two isolation structures 8 are provided between the arc extinguishing mechanism 3 and the contact mechanism 2. The two isolation structures 8 are spaced apart, and an arc-initiating channel is formed between the two isolation structures 8 to avoid the second moving contact part 25. The second moving contact part 25 passes through the arc-initiating channel and contacts the second stationary contact part 24.

[0089] Specifically, the arc extinguishing mechanism 3 is arranged on one side of the contact mechanism 2 along the length of the circuit breaker. The arc extinguishing mechanism 3 includes a mounting base 31 and two mounting plates 32 respectively connected to the mounting base 31. Between the two mounting plates 32, there are multiple arc extinguishing grids 33 arranged along the width of the circuit breaker. The mounting base 31 is provided with an exhaust port, and the arc extinguishing gas is discharged from the exhaust port along the length of the circuit breaker. The multiple arc extinguishing grids 33 are provided with arc extinguishing notches 34 on the side near the contact mechanism 2. Each arc extinguishing grid 33 is provided with arc extinguishing legs 35 on both sides of the arc extinguishing notch 34. The bottoms of the arc extinguishing notches 34 of two adjacent arc extinguishing grids 33 are staggered.

[0090] The isolation structure 8 includes an isolation cover 81 and an isolation platform 82. The isolation covers 81 of the two isolation structures 8 are respectively fitted onto the arc-extinguishing support legs 35 on both sides of the arc-extinguishing grid plate 33. Multiple isolation plates for inserting between two adjacent arc-extinguishing grid plates 33 are provided inside the isolation cover 81. The isolation platforms 82 of the two isolation structures 8 are arranged facing each other, forming an arc-initiating channel between the two isolation platforms 82. The isolation structure 8 can be a gas-generating material, which not only serves to isolate the moving contact, but also generates gas, increases the gas pressure in the arc-extinguishing mechanism 3, and accelerates the discharge of arc-extinguishing gas.

[0091] The switching unit 1 includes two wiring mechanisms 4 that are electrically connected to the stationary contact and the moving contact, respectively, such as... Figure 3 As shown, in a preferred embodiment of the wiring mechanism 4 connected to the stationary contact, the wiring mechanism 4 includes a conductive element and a first connector 41 and a second connector 42 disposed opposite to each other on both sides of the conductive element along the length direction of the circuit breaker. The conductive element is provided with a first stationary contact portion 22. The first connector 41 is connected between the conductive element and the housing. The second connector 42 is connected between the conductive element and the housing. The second connector 42 is provided with a second stationary contact portion 24 and an upper connecting portion 425 extending into the arc extinguishing mechanism 3.

[0092] Furthermore, the second connector 42 includes a first connecting portion 421 and a third connecting portion disposed opposite to each other, and a second connecting portion 422 connected between the first connecting portion 421 and the third connecting portion. The first connecting portion 421 is connected to the housing by a first screw, and the second connecting portion 422 is connected to the conductive element by a second screw. The third connecting portion includes a T-shaped lower connecting portion 424 and an upper connecting portion 425 disposed parallel to the lower connecting portion 424. The upper connecting portion 425 and the lower connecting portion 424 are connected by a middle connecting portion 426. The middle connecting portion 426 is obliquely connected between the parallel lower connecting portion 424 and the upper connecting portion 425. The lower connecting portion 424 is provided with a second static contact portion 24. The upper connecting portion 425 is connected to the housing by a third screw and also includes a central hole, with the two ends of the central hole located on the middle connecting portion 426 and the upper connecting portion 425, respectively.

[0093] It should be noted that in the description of this invention, the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship conventionally placed during use. They are used only for ease of description and do not indicate that the device or element referred to must have a specific orientation. Therefore, they should not be construed as limiting this invention. Furthermore, the terms "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating relative importance.

[0094] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the inventive concept, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A circuit breaker, comprising a housing and an operating mechanism and at least one switching unit (1) respectively disposed in the housing, the switching unit (1) comprising a contact mechanism (2) and an arc-extinguishing mechanism (3), the contact mechanism (2) comprising a moving contact, a stationary contact and a contact support (23), the moving contact being disposed on the contact support (23), the operating mechanism being capable of driving the contact support (23) to rotate, and the moving contact being driven to contact and separate from the stationary contact through the contact support (23), characterized in that: The contact mechanism (2) further includes a contact cover (5) rotatably mounted on the contact support (23). The contact cover (5) includes two rotating parts (51) arranged opposite to each other, and a shielding part (52) connected between the two rotating parts (51). The two rotating parts (51) are arranged opposite to each other on both sides of the contact support (23) and are rotatably connected to the contact support (23) respectively. The rotating part (51) is provided with one of a guide protrusion (6) and a guide groove (7) at an eccentric position, and the housing is provided with the other of a guide protrusion (6) and a guide groove (7). The guide protrusion (6) is slidably inserted into the guide groove (7). The contact support (23) can drive the guide protrusion (6) to slide along the guide groove (7). The guide protrusion (6) and the guide groove (7) drive the contact cover (5) to rotate relative to the contact support (23). When the moving contact and the stationary contact separate, the contact cover (5) rotates to the space between the moving contact and the stationary contact. When the moving contact and the stationary contact are in contact, the contact cover (5) moves away from the space between the moving contact and the stationary contact.

2. The circuit breaker according to claim 1, characterized in that: The stationary contact includes a first stationary contact portion (22), and the moving contact includes a first moving contact portion (21) corresponding to the first stationary contact portion (22). When the first stationary contact (22) separates from the first moving contact (21), the contact cover (5) rotates at least between the first stationary contact (22) and the first moving contact (21). When the first stationary contact (22) contacts the first moving contact (21), the contact cover (5) leaves between the first stationary contact (22) and the first moving contact (21).

3. The circuit breaker according to claim 2, characterized in that: The housing is provided with two opposing partitions for each switch unit (1). The switch unit (1) is located between the two partitions. The two partitions are respectively provided with the two rotating parts (51) of the contact cover (5). The two partitions are respectively provided with guide grooves (7) and the two rotating parts (51) are provided with guide protrusions (6).

4. The circuit breaker according to claim 3, characterized in that: The contact support (23) includes two support plates (231) rotatably connected to the housing, and a support seat (232) disposed between the two support plates (231). The moving contact is rotatably disposed on the support seat (232). A contact spring is provided between the moving contact and the support seat (232). The two rotating parts (51) of the contact cover (5) are disposed on the outside of the two support plates (231). The ends of the two rotating parts (51) away from the stationary contact are rotatably connected to the support plates (231) through rotating shafts (53). The ends of the two rotating parts (51) near the stationary contact are provided with guide protrusions (6).

5. The circuit breaker according to claim 3, characterized in that: The housing includes a base plate (11) and a base (12). The base plate (11) is provided with a first isolation part (13). The base (12) is provided with a second isolation part (14) corresponding to the first isolation part (13). The first isolation part (13) and the second isolation part (14) are used to form a partition. The first isolation part (13) is provided with a first guide structure (71) and a first guide surface (72) is provided on the first guide structure (71). The second isolation part (14) is provided with a second guide structure (73) corresponding to the first guide structure (71) and a second guide surface (74) is provided on the second guide structure (73). The first isolation part (13) and the second isolation part (14) form a partition after the base plate (12) and the base (11) are assembled. The first guide structure (71) and the second guide structure (73) are spaced apart and the first guide surface (72) and the second guide surface (74) are arranged opposite to each other. A guide groove (7) is formed between the first guide surface (72) and the second guide surface (74).

6. The circuit breaker according to claim 5, characterized in that: The first guide surface (72) includes a first pushing segment (721) and a first limiting segment (723) connected together, and the second guide surface (74) includes a second pushing segment (741) and a second limiting segment (743) connected together. The first pushing segment (721) and the second pushing segment (741) are disposed opposite to each other, and the guide groove (7) is formed between the first pushing segment (721) and the second pushing segment (741). When the moving contact moves closer to the stationary contact, the first pushing section (721) pushes the guide protrusion (6), causing the contact cover (5) to rotate away from the moving contact. When the first stationary contact (22) contacts the first moving contact (2), the guide protrusion (6) slides to the side limit of the first limiting section (723) to limit the contact cover (5) to a position away from the moving contact. When the moving contact moves away from the stationary contact, the second pushing section (741) pushes the guide protrusion (6), causing the contact cover (5) to rotate in the direction between the first moving contact part (21) and the first stationary contact part (22). When the contact cover (5) rotates between the first moving contact part (21) and the first stationary contact part (22), the guide protrusion (6) slides to the side limit of the second limiting section (743) to limit the contact cover (5) between the first moving contact part (21) and the first stationary contact part (22).

7. The circuit breaker according to claim 2, characterized in that: The stationary contact also includes a second stationary contact portion (24) located in the arc extinguishing mechanism (3), and the moving contact also includes a second moving contact portion (25) corresponding to the second stationary contact portion (24). The distance from the second moving contact portion (25) to the rotation center of the contact support (23) is greater than the distance from the first moving contact portion (21) to the rotation center of the contact support (23). The second moving contact portion (25) can contact the second stationary contact portion (24) before the first moving contact portion (21) contacts the first stationary contact portion (22). The second moving contact portion (25) separates from the second stationary contact portion (24) after the first moving contact portion (21) separates from the first stationary contact portion (22).

8. The circuit breaker according to claim 7, characterized in that: Two isolation structures (8) are provided between the arc extinguishing mechanism (3) and the contact mechanism (2). The two isolation structures (8) are spaced apart, and an arc-inducing channel is formed between the two isolation structures (8) to avoid the second moving contact part (25). The second moving contact part (25) passes through the arc-inducing channel and contacts the second stationary contact part (24). The arc extinguishing mechanism (3) includes multiple arc extinguishing grid plates (33). Each of the multiple arc extinguishing grid plates (33) has an arc extinguishing notch (34) on the side near the contact mechanism (2). Each arc extinguishing grid plate (33) has an arc extinguishing support (35) on both sides of the arc extinguishing notch (34). One isolation structure (8) is connected to the support on one side of the multiple arc extinguishing grid plates (33), and the other isolation structure (8) is connected to the support on the other side of the multiple arc extinguishing grid plates (33). The isolation structure (8) includes an isolation cover (81) and an isolation platform (82). The isolation covers (81) of the two isolation structures (8) are respectively fitted onto the arc extinguishing support (35) on both sides of the arc extinguishing grid plates (33). Multiple isolation plates for insertion between two adjacent arc extinguishing grid plates (33) are provided inside the isolation cover (81). The isolation platforms (82) of the two isolation structures (8) are arranged facing each other, forming an arc-initiating channel between the two isolation platforms (82).

9. The circuit breaker according to claim 7, characterized in that: The wiring mechanism (4) is connected to the stationary contact. The wiring mechanism (4) includes a conductive element and a first connector (41) and a second connector (42) disposed opposite to each other on both sides of the conductive element. The conductive element is provided with a first stationary contact portion (22). The first connector (41) is connected between the conductive element and the housing. The second connector (42) is connected between the conductive element and the housing. The second connector (42) is provided with a second stationary contact portion (24) and an upper connecting portion (425) extending into the arc extinguishing mechanism (3) (6).

10. The circuit breaker according to claim 1, characterized in that: The shielding part (52) includes a first shielding part (521) in planar shape and a second shielding part (522) in arc shape. The second shielding part (522) is located on the side of the first shielding part (521) near the arc extinguishing mechanism (3). The end of the rotating part (51) connected to the shielding part (52) is fan-shaped. The end of the rotating part (51) away from the shielding part (52) is rotatably connected to the contact support (23) through the rotating shaft (3). The guide protrusion (6) on the rotating part (51) is located at the end near the shielding part (52).

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