CN117373876A - Circuit breaker and power distribution cabinet - Google Patents

Abstract

The invention relates to a circuit breaker and a power distribution cabinet comprising such a circuit breaker, the circuit breaker comprising: a breaking unit pair configured to switch between a closing position in which the circuit breaker is turned on and a breaking position in which the circuit breaker is turned off; and an operating mechanism comprising a driving member configured to actuate the breaking unit to switch between a closing position and a breaking position; the two breaking units in the pair of breaking units are respectively arranged at two sides of the operating mechanism, and the two breaking units in the pair of breaking units are in transmission connection through the driving piece.

Description

Circuit breaker and power distribution cabinet

Technical Field

The present invention relates to a circuit breaker and a power distribution cabinet comprising such a circuit breaker.

Background

Along with the continuous promotion of policies such as green low carbon, the development and utilization of new energy become the focus of attention, and corresponding business also rapidly develops. The direct current circuit breaker also becomes a wind gap of technical innovation, in particular to the improvement of the voltage capability of the circuit breaker. The technology of the direct current circuit breaker is continuously developed, and the technology is developed from the previous 1000V arc voltage quadrupole string to 1200V arc voltage quadrupole string, 1500V arc voltage triode string and 1500V arc voltage diode string. The technological development trend of products with the same performance is that the arc voltage of each pole is larger, the volume is smaller and smaller, and the cost is lower and lower.

In addition, some dc circuit breakers are structured differently from conventional circuit breakers, for example, a single-break structure is employed, and thus the accessories and installation size are also different from conventional circuit breakers, which increases the integration cost of the product. The cost increase for the production of smaller production capacity dc circuit breakers is obviously significant compared to the multiplexing of conventional general purpose accessories. Furthermore, significant changes in the height dimensions of the terminals of these dc breakers can also increase the integration cost of a power distribution cabinet (e.g., a power distribution cabinet).

On the other hand, with the circuit breaker of the double-break structure, it is difficult to obtain a higher arc voltage because of insufficient opening distance.

Thus, there is a need for a cost-effective circuit breaker with a larger opening distance, providing an arc voltage of 1500V or even higher.

Disclosure of Invention

In view of the above-mentioned problems and needs, the present invention proposes a novel circuit breaker, which solves the above-mentioned problems and brings about other technical effects due to the following technical features.

In one aspect, the present invention provides a circuit breaker comprising: a breaking unit pair configured to switch between a closing position in which the circuit breaker is turned on and a breaking position in which the circuit breaker is turned off; and an operating mechanism comprising a driving member configured to actuate the breaking unit to switch between a closing position and a breaking position; the two breaking units in the pair of breaking units are respectively arranged at two sides of the operating mechanism, and the two breaking units in the pair of breaking units are in transmission connection through the driving piece.

In some examples, each breaking unit of the pair of breaking units comprises a stationary contact and a movable contact assembly pivotable relative to the stationary contact, in the closed position the stationary contact is in contact with a movable contact of the movable contact assembly, in the open position the stationary contact is separated from the movable contact assembly, wherein the movable contact assembly is pivoted about a first axis and comprises a driven aperture spaced from the first axis.

In some examples, the drive member includes a body and a pair of drive arms extending from either side of the body that cooperate with the driven aperture to transmit rotational torque.

In some examples, the operating mechanism further comprises a base to which the drive is pivotally mounted and pivots about a second axis that is parallel or coincident with the first axis.

In some examples, the operating mechanism further includes a first link and a second link, the first link pivoting about a third axis parallel to the second axis, and the second link forming a revolute pair connection with the first link and the body, respectively, thereby forming a four-bar mechanism.

In some examples, the second link is at a distance L1 from the third axis to the revolute pair connection point of the first link and at a distance L2 from the second axis to the revolute pair connection point of the main body, wherein L1 is greater than L2.

In some examples, the operating mechanism further includes a drive mechanism configured to actuate the pivoting of the first link, thereby actuating the pivoting of the movable contact assembly.

In some examples, each breaking unit of the pair of breaking units further comprises an arc chute in which the stationary contact and the moving contact assembly are housed.

In some examples, the moving contact assembly includes a pair of moving contacts symmetrically distributed in a radial direction, the fixed contacts include a first fixed contact and a second fixed contact respectively arranged near the pair of moving contacts, and the movement of the pair of moving contacts relative to the fixed contacts forms a movement track.

In some examples, the arc extinguishing chamber is provided with an air passage on the radial outer side of the whole movement track, the air passage comprises a first end close to the first fixed contact and/or the second fixed contact and a second end far away from the first end, and the second end is provided with an air outlet.

In some examples, a plurality of arc extinguishing grid sheets are arranged in sequence in the air passage, the first end is provided with an arc striking sheet, and the second end is provided with a discharge sheet.

In some examples, the first stationary contact and/or the second stationary contact are arranged in a horizontal direction.

In some examples, each of the plurality of arc chute sheets is disposed in a horizontal direction or forms the same included angle with the horizontal direction.

In some examples, the end surface envelopes of the plurality of arc extinguishing gate sheets are arranged in a circular arc shape.

In some examples, the first stationary contact and/or the second stationary contact are arranged in a substantially radial direction.

In some examples, an end surface envelope of the plurality of arc extinguishing gate sheets is set as an involute with respect to the motion trajectory, and wherein an inner wall of the air passage on a side away from the moving contact assembly is also set as an involute with respect to the motion trajectory.

In some examples, the circuit breaker further comprises: and the release is arranged at one side of the operating mechanism away from the breaking unit pair, and is configured to actuate the driving piece to break the breaker when the overcurrent threshold is triggered.

In some examples, the circuit breaker is a direct current bipolar circuit breaker.

In another aspect, the invention provides a power distribution cabinet comprising a circuit breaker as described above.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly described below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure, not to limit the present disclosure.

Fig. 1 illustrates a perspective view of a circuit breaker in accordance with at least one embodiment of the present disclosure;

fig. 2 illustrates a partially exploded view of a circuit breaker in accordance with at least one embodiment of the present disclosure;

fig. 3 shows a partial view of the operating mechanism of the circuit breaker of fig. 2;

FIG. 4 illustrates a base of an operating mechanism in accordance with at least one embodiment of the present disclosure;

FIG. 5 illustrates a driver of an operating mechanism in accordance with at least one embodiment of the present disclosure;

FIG. 6 illustrates a perspective view of an operating mechanism in accordance with at least one embodiment of the present disclosure;

FIG. 7 illustrates a partial view of the operating mechanism shown in FIG. 6;

FIG. 8 illustrates another partial view of the operating mechanism illustrated in FIG. 6, with the driver omitted;

FIG. 9 illustrates a perspective view of a second link in accordance with at least one embodiment of the present disclosure;

fig. 10 illustrates a cross-sectional view of a breaking unit according to at least one embodiment of the present disclosure;

fig. 11 shows a cross-sectional view of a breaking unit according to another embodiment of the present disclosure;

fig. 12 shows a cross-sectional view of a breaking unit according to a further embodiment of the present disclosure;

fig. 13 shows a cross-sectional view of a breaking unit according to a further embodiment of the present disclosure.

Detailed Description

In order to make the objects, technical solutions and advantages of the technical solutions of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of specific embodiments of the present invention. Like reference numerals in the drawings denote like parts. It should be noted that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be made by a person skilled in the art without creative efforts, based on the described embodiments of the present invention fall within the protection scope of the present invention.

Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The terms "first," "second," and the like in the description and in the claims, are not used for any order, quantity, or importance, but are used for distinguishing between different elements. Likewise, the terms "a" or "an" and the like do not necessarily denote a limitation of quantity. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.

Various embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Here, it is to be noted that in the drawings, the same reference numerals are given to constituent parts having substantially the same or similar structures and functions, and repeated description thereof will be omitted. For ease of description, the drawings of the embodiments shown in the present disclosure omit parts of elements such as a breaker housing, an operating mechanism, and/or a housing of a breaking unit, etc.

Possible implementations within the scope of the present disclosure may have fewer components, have other components not shown in the drawings, different components, differently arranged components, differently connected components, etc., than the examples shown in the drawings. Furthermore, two or more of the components in the figures may be implemented in a single component or a single component shown in the figures may be implemented as multiple separate components without departing from the concepts of the present disclosure.

The breaking unit and the operating mechanism are indispensable components in the circuit breaker, the breaking unit comprises a fixed contact and a moving contact assembly, and the moving contact assembly can move (not limited to pivot movement or linear movement) relative to the fixed contact assembly, so that the breaking and closing actions are completed. Correspondingly, the breaking unit can be switched between a closing position and a breaking position, and in the closing position, the fixed contact is contacted with a moving contact in the moving contact assembly, so that the circuit breaker is conducted; in the opening position, the fixed contact is separated from the moving contact assembly, so that the circuit breaker is opened. The operating mechanism is an actuating mechanism for actuating the opening and closing actions of the breaking unit, and can be manually driven or automatically driven, for example, through auxiliary parts such as a release.

As shown in fig. 1, a circuit breaker according to at least one embodiment of the present disclosure includes a pair of breaking units 1,2, an operating mechanism 3, and a release 4, the breaking units 1 and 2 being disposed at both sides of the operating mechanism 3, respectively, and being drivingly connected to each other by a driving member 31 of the operating mechanism 3. As shown in fig. 1, the breaking unit 2 and the operating mechanism are arranged side by side in sequence, and the release 4 is arranged at the rear side of the operating mechanism 3 away from the breaking units 1,2 to obtain a space required for coordination with the operating mechanism 3. The trip unit 4 is configured to actuate the drive member 31 to trip the circuit breaker upon triggering of the overcurrent threshold.

Unlike the existing single-pole circuit breaker (having only one breaking unit) or multi-pole circuit breaker, the bipolar circuit breaker proposed by the present disclosure is arranged such that the breaking units are disposed on both sides of the operating mechanism, respectively, and the driving members are of a symmetrical configuration (to be described in detail later) such that respective moving contacts of a pair of breaking units achieve synchronous movement. Compared with a three-pole circuit breaker product, the bipolar circuit breaker provided by the disclosure has the appearance similar to that of a standard three-pole circuit breaker product, so that the universality of accessories, the installation habit of the accessories and the like can be realized, and the user installation interface is friendly.

Furthermore, based on the concept of the symmetrical arrangement of the bipolar circuit breaker of the present disclosure, other double-pole circuit breaker arrangements, such as four-pole, six-pole or more-pole circuit breakers, can be extended.

The actuation principle of the release 4 can be seen from fig. 2. As shown in fig. 2, the trip unit 4 includes a movable trip push rod 41 and a trip driving member 42 cooperating with the trip push rod 41, and the operating mechanism 3 cooperates with the trip unit 4 (specifically, the trip driving member 42) to implement trip protection when an overcurrent (overload current and/or short-circuit current) occurs in the circuit breaker, and the trip unit 4 is, for example, a thermomagnetic type or an electronic type trip unit. When the threshold value is triggered during overcurrent of the release 4, the release push rod 41 shown in fig. 2 moves rightward to push the release driving piece 42 to rotate clockwise, so that the release piece 34 of the operating mechanism 3 is actuated, the operating mechanism 3 is released, and the operating mechanism 3 drives the movable contact assembly 10 to rotate anticlockwise to break the brake, so that the overcurrent is cut off. The operation of the operating mechanism 3 to actuate the movable contact assembly 10 will be described in detail with reference to fig. 6 to 8.

It should be noted that, the trip driving member 42 is not necessary, and the trip driving member 42 may be omitted when the trip push rod 41 is at a higher position. At this time, the trip push rod 41 directly pushes the trip piece 34 to realize trip opening of the operating mechanism 3.

Referring again to fig. 2, the movable contact assembly 10 rotates about a first axis D1, the first axis D1 being generally in the direction of the connecting line between the breaking unit pairs 1, 2. The moving contact assembly 10 includes a generally cylindrical moving contact bracket 11 and a pair of moving contact arms 13 extending symmetrically radially outward from the moving contact bracket 11, and a driven hole 12 arranged in spaced relation to the first axis D1. A pair of moving contacts 14 are respectively provided at the ends of the moving contact arms 13 so as to be also symmetrically distributed in the radial direction, and the pair of moving contacts 14 are electrically connected to each other. The construction of such a moving contact assembly 10 shown in fig. 2 may also be referred to as a double-break construction, and correspondingly, the breaking units 1,2 may also be provided with a pair of stationary contacts, each configured to be in contact with the pair of moving contacts 14. The double breakpoint configuration requires less contact breaking force than the single breakpoint configuration, but due to size limitations, the over travel and opening of the contacts can be limited, thereby limiting the arc voltage.

Thus, increasing the over travel and the open distance of the double breakpoint configuration is critical to increasing the arc voltage. The drive mechanisms in the operating mechanism of conventional circuit breakers are typically small in drive stroke because they do not require such a large opening distance as a direct current circuit breaker. In order to multiplex these drive mechanisms, a larger opening distance is ensured at the same time, and therefore more arc extinguishing bars can be arranged in the arc extinguishing chamber, so that a larger arc voltage is obtained, and the breaking capacity of the circuit breaker is improved.

In this regard, the present disclosure proposes a new mechanism configuration, which adds a set of four-bar mechanisms on the basis of multiplexing the conventional driving mechanism, and obtains a larger opening by setting the size of the bar. Described in detail below in connection with fig. 3-9.

The moving contact assembly 10 is omitted from fig. 3, so that the driving member 31 may be shown. As shown in fig. 3 to 9, the operating mechanism 3 may include a base 5, a driving mechanism 30, a driving piece 31, a first link 32, a second link 33, a handle 34, a third link 35, and a fourth link 36. The drive member 31 is pivotable about a second axis D2, the projection of the second axis D2 on the plane being reduced to a point, since fig. 3 is a plan view. The second axis D2 may be parallel to the first axis D1 or coincident therewith, i.e. the driving member 31 is arranged coaxially with the moving contact assembly 10. The operating mechanism 3 may include a drive mechanism 30, and the drive mechanism 30 may be an off-the-shelf circuit breaker drive mechanism that may be manually actuated via a handle 34 or actuated by the trip unit 4 as previously described. The drive mechanism 30 ultimately actuates the first link 32. The first link 32 pivots about a third axis D3 parallel to the second axis D2, and the second link 33 forms a revolute pair connection with the first link 32 and the driving member 31, respectively, thereby forming a four-bar linkage.

Fig. 4 shows the base 5 of the operating mechanism 3, the base 5 may have a through slot in the middle and a mounting portion 51 extending from the through slot for pivotally mounting the driver 31. It should be noted that all the revolute pair connections shown in the present disclosure may be installed in a manner such as pin-and-hole fitting, but the present disclosure is not limited thereto.

Fig. 5 shows a detail view of the driver 31. The driver 31 may include a generally cylindrical body 310 and a pair of drive arms 311 extending from opposite sides of the body 310, the pair of drive arms 311 cooperating with the driven bore 12 to transmit rotational torque, e.g., extending into the driven bore 12. The driving member 31 may further include a hook 313, a link mounting groove 312, and a fitting groove 314. The hook 313 is configured to pass a revolute pair connection pin. The link installation groove 312 is located at the middle of the hook 313 for insertion installation of the second link 33. The fitting groove 314 is formed at the bottom of the body 310 for fitting with the mounting portion 51 of the base 5.

Fig. 6 shows a topology of the operating mechanism 3, and in order to facilitate an intuitive understanding of the course of movement of the multi-link mechanism, the individual revolute pair connection points O1 to O6, and the center of rotation O7 of the handle 34, are marked in fig. 6. In this embodiment, O1O2, O2O3, O3O4, O4O1 constitute a first set of four-bar linkages, and O4O3, O3O5, O5O6, O6O4 constitutes a second set of four-bar linkages.

Fig. 6 shows the position of the movable contact in the closed state, and the handle 34 is pushed to rotate counterclockwise around O7. A return spring is provided between the handle 34 and the third link 35, and as the handle 34 rotates, the spring force line rotates counterclockwise, and when the spring force line passes over O1, the spring force drives the third link 35 to rotate clockwise, and the fourth link 36 rotates counterclockwise, thereby driving the first link 32 to rotate counterclockwise. For the second set of four-bar linkage consisting of the first link 32, the second link 33 and the driving member 31, the first link 32 rotates counterclockwise to cause the driving member 31 to rotate counterclockwise, and drives the moving contact assembly 10 to rotate counterclockwise, so as to realize the opening operation, as shown in fig. 6 to 8. The closing operation is the opposite process and is not described in detail here.

By adjusting the setting of the lengths of O5O6 and O3O4, the over travel and the opening distance of the moving contact can be adjusted. Specifically, the distance between the revolute pair connection point O3 of the second link 33 and the first link 32 and the third axis D3 (i.e., O4) is L1, the distance between the revolute pair connection point O5 of the second link 33 and the main body 310 of the driver 31 and the second axis D2 (i.e., O6) is L2, and L1 is greater than L2. Therefore, the rotation of the smaller angular travel of the original first link 32 can be switched to the rotation of the larger angular travel of the present driving member 31, thereby increasing the opening distance of the moving contact.

Fig. 9 shows a part view of the second link 33, and both ends of the second link 33 are provided with through holes for mounting the revolute pairs, respectively.

Thanks to the above-described arrangement of the operating mechanism 3, the circuit breaker according to the present disclosure can have a larger contact opening, and accordingly can be provided with a larger size of arc extinguishing chamber and more arc extinguishing gate sheets, thereby obtaining a higher arc voltage. Fig. 10 to 13 show a number of alternative embodiments of the arc chute. For ease of illustration, only one side of the arc chute is identified in the embodiment of fig. 10-13, it being readily understood that the other side is centrally disposed therewith and therefore not shown for simplicity.

As shown in fig. 10, the breaking unit 1,2 comprises an arc extinguishing chamber 20. The first stationary contact 6, the second stationary contact 7 and the moving contact assembly 10 are accommodated in the arc extinguishing chamber 20. The movement of the pair of moving contacts 14 of the moving contact assembly 10 relative to the first and second fixed contacts 6,7 forms movement trajectories P1, P2. Since the moving contact assembly 10 performs the circumferential pivoting motion, it can be known that the motion trajectories P1, P2 are circular arc trajectories. The first stationary contact 6 may be connected to the first terminal 8 by a copper bar, and the second stationary contact 7 may be connected to the second terminal 9 by a copper bar. Illustratively, the first terminal 8 may be connected to an external power source and the second terminal 9 may be connected to a load, so that when the moving and stationary contacts are in contact, current flows from the first terminal 8 through the first stationary contact 6 and the pair of moving contacts 14, and then through the second stationary contact 7 and the second terminal 9 to the load, thereby switching the load into the external power source. The wiring of the present disclosure is not limited thereto, and the first terminal 8 may also be connected to a load, and correspondingly the second terminal 9 is connected to an external power source.

An air passage 21, an air outlet 22, a plurality of arc extinguishing gate sheets 23, an arc striking sheet 24 and an arc extinguishing sheet 25 may be provided in the arc extinguishing chamber 20. The air passage 21 may be disposed radially outward of at least part of the movement trajectories P1, P2, for example, in the present embodiment, radially outward of the entire movement trajectories P1, P2. The air duct 21 comprises a first end 211 close to the first stationary contact 6 and the second stationary contact 7 and a second end 212 remote from the first end 211, an air outlet 22 being provided at the second end 212 for diverting and extinguishing the arc.

The plurality of arc extinguishing bars 23 are arranged side by side in sequence along the air duct 21. Since the circuit breaker of the present disclosure has a larger moving contact movement distance, it is possible to provide a longer air passage 21 and to arrange more arc extinguishing gate pieces 23. In addition, the striking plate 24 is disposed at the first end 211 of the air passage 21, the discharge plate 25 is disposed at the second end 212 of the air passage 21, and the striking plate 24 and the discharge plate 25 may be metal plates commonly used in the art.

When the moving contact 14 is separated from the stationary contacts 6,7, an arc is generated between the moving and stationary contacts. Then, the arc root on the fixed contact is quickly separated from the fixed contact along the striking plate 24 under the driving of electromagnetic force, so that the arc root enters the arc extinguishing chamber 20, and meanwhile, the arc root on the movable contact is quickly separated from the movable contact under the driving of electromagnetic force, so that the arc root reaches the upper part of the movable contact 14. With further opening movement of the moving contact 14, the arc is elongated, enters the arc extinguishing chamber and is cut off by the arc extinguishing gate sheet 23, and the arc voltage continues to increase. When the moving contact 14 is at a relatively short distance from the discharge sheet 25 and is close to the air outlet 22, the electric arc burns between the discharge sheet 25 and the striking sheet 24 after passing through the moving contact 14, and a high and durable arc voltage is formed, so that the fault current rapidly drops until the fault current is extinguished.

In the embodiment shown in fig. 10, the first stationary contact 6 and the second stationary contact 7 are arranged in the horizontal direction a. The horizontal direction a is the direction from left to right in fig. 10. Further, each of the plurality of arc extinguishing gate sheets 23 is also arranged in the horizontal direction.

Note that, differences between the embodiments and the embodiment shown in fig. 10 will be described with emphasis, and undescribed or omitted portions are similar or identical to those of the embodiment shown in fig. 10.

Alternatively, in the embodiment shown in fig. 11, the first fixed contact 6 and the second fixed contact 7 are arranged along the horizontal direction a, and each of the plurality of arc extinguishing gate sheets 23 forms the same angle with the horizontal direction a. Accordingly, the striking plate 24 and the discharge plate 25 are also arranged parallel to the arc extinguishing grid plate 23.

Alternatively, in the embodiment shown in fig. 12, the first stationary contact 6 and the second stationary contact 7 are arranged in the horizontal direction a, and the end surface envelopes of the plurality of arc extinguishing gate sheets 23 are provided in a circular arc shape. In particular, the circular arc shape may be a circular arc concentric with the rotation center of the movable contact assembly 10.

Alternatively, in the embodiment shown in fig. 13, the first stationary contact 6 and the second stationary contact 7 are arranged in a substantially radial direction, thus also at an angle with respect to the horizontal direction a. In this way, a greater number of arc extinguishing bars 23 can be accommodated in a limited space.

In this embodiment, the end surface envelope of the plurality of arc extinguishing gate sheets 23 is set to be involute with respect to the movement trajectories P1, P2. The inner wall 26 of the air duct 21 on the side remote from the moving contact assembly 10 is also provided as an involute with respect to the movement trajectories P1, P2. That is, from the first end 211 to the second end 212, the distance from the arc extinguishing bar 23 to the movement trajectories P1, P2 gradually increases, and the distance from the inner wall 26 to the movement trajectories P1, P2 also gradually increases.

The foregoing illustrates exemplary embodiments of the arc chute presented in the present disclosure, and those skilled in the art may prefer according to actual conditions to achieve optimal arc extinguishing effects and higher arc voltages.

In summary, compared with the existing products, the circuit breaker provided by the embodiment of the disclosure has a larger opening distance, so that when the direct current is disconnected, an arc voltage greater than that of the prior art can be obtained. For example, test data show that twice the arc voltage of the prior art can be obtained, so that fault current reaching 750V working voltage can be cut off by a single pole, and 1500V working voltage can be cut off by connecting two poles in series. The functions which can not be realized by the prior art are completed by adopting fewer parts, and the same performance is achieved, so that the probability of faults is reduced. Furthermore, unnecessary screw joints are eliminated, thereby reducing the risk of fire due to poor joints.

In addition, the circuit breaker provided by the disclosure can reuse a mature circuit breaker driving mechanism, so that the project development period is greatly shortened, the cost is saved, the installation space is saved, and the performance is reliable.

On the other hand, the disclosure also provides a power distribution cabinet, which comprises the circuit breaker. Because the circuit breaker saves size and installation space, the switch board that this disclosure presented can install more circuit breakers under the same size's circumstances.

The exemplary embodiments of the circuit breaker and the power distribution cabinet according to the present invention have been described in detail hereinabove with reference to preferred embodiments, however, it will be understood by those skilled in the art that various modifications and adaptations to the specific embodiments described above may be made without departing from the concept of the present invention. In addition, various technical features and structures presented in various aspects of the present invention may be combined in various ways without departing from the scope of the invention, which is defined by the appended claims.

Claims (19)

1. A circuit breaker, comprising:

a breaking unit pair configured to switch between a closing position in which the circuit breaker is turned on and a breaking position in which the circuit breaker is turned off; and

the operating mechanism comprises a driving piece, wherein the driving piece is configured to actuate the breaking unit to switch between a closing position and a breaking position;

the two breaking units in the pair of breaking units are respectively arranged at two sides of the operating mechanism, and the two breaking units in the pair of breaking units are in transmission connection through the driving piece.

2. The circuit breaker of claim 1, wherein each breaking unit of the pair of breaking units comprises a stationary contact and a movable contact assembly pivotable relative to the stationary contact, in the closed position the stationary contact is in contact with a movable contact in the movable contact assembly, in the open position the stationary contact is separated from the movable contact assembly, wherein the movable contact assembly pivots about a first axis and comprises a driven aperture spaced from the first axis.

3. The circuit breaker of claim 2, wherein the drive member comprises a body and a pair of drive arms extending from both sides of the body, the pair of drive arms cooperating with the driven aperture to transmit rotational torque.

4. The circuit breaker of claim 3, wherein the operating mechanism further comprises a base, the drive member being pivotally mounted to the base and pivoting about a second axis, the second axis being parallel or coincident with the first axis.

5. The circuit breaker of claim 4, wherein the operating mechanism further comprises a first link and a second link, the first link pivoting about a third axis parallel to the second axis, and the second link forming a revolute pair connection with the first link and the body, respectively, thereby forming a four-bar mechanism.

6. The circuit breaker of claim 5, wherein a revolute pair connection point of the second link and the first link is at a distance L1 from the third axis and a revolute pair connection point of the second link and the main body is at a distance L2 from the second axis, wherein L1 is greater than L2.

7. The circuit breaker of claim 5, wherein the operating mechanism further comprises a drive mechanism configured to actuate the pivoting of the first link, thereby actuating the pivoting of the movable contact assembly.

8. The circuit breaker of any of claims 2 to 7, wherein each breaking unit of the pair of breaking units further comprises an arc chute, the stationary contact and the moving contact assembly being housed within the arc chute.

9. The circuit breaker of claim 8, wherein the moving contact assembly comprises a pair of moving contacts symmetrically distributed in a radial direction, the fixed contacts comprising a first fixed contact and a second fixed contact respectively disposed adjacent to the pair of moving contacts, the movement of the pair of moving contacts relative to the fixed contacts forming a movement trace.

10. The circuit breaker of claim 9, wherein the arc chute is provided with an air channel radially outward of at least a portion of the motion profile, the air channel comprising a first end proximate the first stationary contact and/or the second stationary contact and a second end distal from the first end, the second end being provided with an air outlet.

11. The circuit breaker of claim 10, wherein a plurality of arc chute blades are disposed in sequence within the air path, and the first end is provided with an arc striking blade and the second end is provided with a discharge blade.

12. The circuit breaker of claim 11, wherein the first stationary contact and/or the second stationary contact are arranged in a horizontal direction.

13. The circuit breaker of claim 12, wherein each of the plurality of arc chute blades is disposed in a horizontal direction or forms the same included angle with the horizontal direction.

14. The circuit breaker of claim 12, wherein an end surface envelope of the plurality of arc chute plates is provided in a circular arc shape.

15. The circuit breaker of claim 11, wherein the first stationary contact and/or the second stationary contact are arranged in a generally radial direction.

16. The circuit breaker of claim 15, wherein an end surface envelope of the plurality of arc extinguishing gate sheets is provided as an involute to the motion trajectory, and wherein an inner wall of the air passage on a side remote from the moving contact assembly is also provided as an involute to the motion trajectory.

17. The circuit breaker of claim 1, further comprising: and the release is arranged at one side of the operating mechanism away from the breaking unit pair, and is configured to actuate the driving piece to break the breaker when the overcurrent threshold is triggered.

18. The circuit breaker of claim 1, wherein the circuit breaker is a direct current bipolar circuit breaker.

19. A power distribution cabinet comprising a circuit breaker according to any one of claims 1 to 18.