Circuit breaker

Abstract

The utility model relates to a circuit breaker. The circuit breaker includes: a housing; a handle pivotally mounted to the housing; the two contact groups are arranged in the shell at intervals, and each contact group comprises a static contact and a moving contact capable of moving relative to the static contact; the operating mechanism is connected between the handle and the two contact groups and is shared by the two contact groups, the operating mechanism has a locking state and an unlocking state, in the locking state, the operating mechanism can be driven by the handle to keep the respective moving contacts of the two contact groups in a state of being connected with the static contacts, and in the unlocking state, the operating mechanism can be driven by the handle to keep the respective moving contacts of the two contact groups in a state of being connected with the static contacts. The moving contacts and the static contacts of the two contact groups can be separated under the driving of the handle; and the two short-circuit opening mechanisms are respectively connected to the static contacts of the two contact groups in the shell, and the two short-circuit opening mechanisms are configured to respectively respond to a first preset current condition to drive the operating mechanism to be in an unlocking state so as to allow the static contacts to be separated from the moving contacts.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit protection switch device technical field especially relates to circuit breaker. BACKGROUND

[0002] Circuit breaker (CB) is widely used in industrial production and daily life, can be connected or disconnected in the power system normal operation loop, also can be in time cut off the loop when the power system appears short circuit or overload fault, thereby effectively protecting the electrical equipment in the loop.

[0003] For a long time, how to improve the structure of circuit breaker to make it more compact, to improve the performance of circuit breaker, is the focus of the industry. SUMMARY

[0004] The utility model aims at providing a kind of circuit breaker, at least can solve the above-mentioned part technical problem.

[0005] According to one aspect of the utility model, a kind of circuit breaker is provided, comprising: shell;Handle, pivotally installed in the shell;Two contact groups, are arranged at intervals in the shell, and each include static contact and the movable contact that can be moved relative to the static contact;Operating mechanism, connected between the handle and the two contact groups and shared by the two contact groups, the operating mechanism has locking state and unlocking state, in locking state, the operating mechanism can be driven by the handle to keep the movable contact of the two contact groups respectively in the state of engagement with static contact, also can be driven by the handle to separate the movable contact of the two contact groups respectively with static contact;Two short-circuit tripping mechanisms, respectively connected to the static contact of the two contact groups in the shell, the two short-circuit tripping mechanisms are configured to be able to each respond to first preset current condition to drive the operating mechanism to be in unlocking state, to allow the static contact and the movable contact separate.

[0006] According to the circuit breaker provided in the scheme, the operating mechanism arranged in the shell can control the action of the movable contact in the two contact groups under the drive of a single handle, realize the breaking and closing of circuit breaker. Two contact groups each correspond to a short-circuit tripping mechanism, and are all accommodated in a shell, so that the layout is reasonable, and the structure is more compact. The 2P circuit accessed by the two contact groups can be applied in series or separately, so that the circuit breaker has a wide range of applications.

[0007] In some embodiments, the circuit breaker includes two overload tripping mechanisms arranged at intervals in the shell, the two overload tripping mechanisms are respectively connected to the movable contact of the two contact groups, and are configured to be able to each respond to second preset current condition to drive the operating mechanism to be in unlocking state, to allow the static contact and the movable contact separate.

[0008] In some embodiments, the circuit breaker includes two arc extinguishing mechanisms arranged in the housing corresponding to the two contact sets.

[0009] In some embodiments, the circuit breaker includes two sets of terminal connections arranged in the housing and connected to the two contact sets respectively, wherein one terminal connection of each set of terminal connections is connected to the moving contact of the corresponding contact set, and the other terminal connection is connected to the stationary contact of the corresponding contact set.

[0010] In some embodiments, the housing has a thickness, the two short-circuit tripping mechanisms are parallel to each other, and are arranged in another direction perpendicular to the thickness direction.

[0011] In some embodiments, the housing includes a first housing part and a second housing part connected detachably, and a partition part clamped between the first housing part and the second housing part, the partition part forms a support for supporting the two short-circuit tripping mechanisms, and the partition part and the first housing part and the second housing part form a containing space for containing an arc extinguishing mechanism respectively.

[0012] In some embodiments, the operating mechanism includes a contact support pivotally mounted to the housing, a lock catch pivotally connected to the contact support and connected to the handle, and a trip unit pivotally connected to the contact support, the trip unit can be pressed against the lock catch to place the operating mechanism in the locked state, and can be disengaged from the lock catch to place the operating mechanism in the unlocked state.

[0013] In some embodiments, the operating mechanism includes a trip unit biasing member, one end of the trip unit biasing member abuts against the contact support, the other end abuts against the trip unit, and the trip unit biasing member applies a biasing force to the trip unit towards the lock catch.

[0014] In some embodiments, a moving contact biasing member is provided for each moving contact, one end of the moving contact biasing member abuts against the contact support, the other end abuts against the moving contact, and the moving contact biasing member applies a biasing force to the moving contact towards the stationary contact.

[0015] In some embodiments, a contact support biasing member is pressed between the contact support and the housing, and the contact support biasing member applies a biasing force to the contact support away from the stationary contact.

[0016] Some of the other features and advantages of the present application will become apparent from the specification, and from the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0017] Embodiments of the present application will be described below in detail with reference to the accompanying drawings, in which:

[0018] Figure 1 is a schematic view of a circuit breaker according to an embodiment of the present application;

[0019] Figure 2 is an exploded schematic view of a circuit breaker housing according to an embodiment of the present application;

[0020] Figure 3 is a schematic view of the interior of a circuit breaker according to an embodiment of the present application, shown from the angle of one housing part removed;

[0021] Figure 4 is a schematic view of the interior of a circuit breaker according to an embodiment of the present application, shown from the angle of another housing part removed;

[0022] Figure 5 is a schematic view of the interior of a circuit breaker according to an embodiment of the present application, shown from the angle of another housing part removed;

[0023] Figure 6 is a schematic view of the interior of a circuit breaker according to an embodiment of the present application, shown from the angle of another housing part removed;

[0024] Explanation of reference signs

[0025] 1 - circuit breaker; 2 - housing; 201 - first accommodation space; 202 - second accommodation space; 20 - first housing part; 21 - second housing part; 22 - middle partition; 221 - first support; 222 - second support; 23 - window; 24 - first terminal; 25 - second terminal; 26 - third terminal; 27 - fourth terminal; 3 - handle; 31 - handle biasing member; 32 - connecting rod; 4 - operating mechanism; 41 - catch; 42 - trip member; 421 - trip member biasing member; 43 - contact support; 44 - indicating member; 5 - first movable contact; 51 - first movable contact biasing member; 50 - second movable contact; 501 - second movable contact biasing member; 6 - first stationary contact; 60 - second stationary contact; 7 - first short-circuit opening mechanism; 70 - second short-circuit opening mechanism; 8 - first overload opening mechanism; 80 - second overload opening mechanism; 9 - first arc extinguishing mechanism; 90 - second arc extinguishing mechanism DETAILED DESCRIPTION

[0026] Reference will now be made in detail to the exemplary embodiments of the present technology, one or more examples of which are illustrated in the drawings. While the attached drawings are intended to provide a further understanding of the present technology, it is not intended that the present technology be limited to the embodiments illustrated in the drawings. In fact, it is expected that the present technology can include a wide variety of embodiments and can be practiced in a number of different ways. Moreover, the drawings are not necessarily drawn to scale. Some of the components in the drawings can be shown in a position that is adjusted according to the actual needs, without affecting the technical effects. The phrase "in the drawings" or similar language appearing in the specification is not to be construed as a reference to the attached drawings only, or to the examples only, unless explicitly so stated.

[0027] Certain directional terms used herein for the purpose of describing the drawings, such as "inner", "outer", "upper", "lower" and other directional terms, will be understood to have their normal meanings and refer to those directions involved when viewing the drawings normally. Unless otherwise indicated, the directional terms described in the specification are substantially in accordance with the conventional directions understood by those skilled in the art.

[0028] The terms "first", "the first", "second", "the second", and similar terms used in the present technology do not indicate any order, number or importance, but are used to distinguish one component from another component.

[0029] Figure 1 An exemplary circuit breaker 1 (e.g. miniature circuit breaker) is shown. As shown, the circuit breaker 1 has a housing 2 and a handle 3 mounted to the housing 2, an operating mechanism 4, a contact assembly, a tripping mechanism and an arc extinguishing mechanism. As Figure 2 In detail, the housing 2 comprises two opposing half-shells, a first shell portion 20 and a second shell portion 21, which are detachably connected together along the thickness direction. Sandwiched between the two half-shells is a partition portion 22. The partition portion 22 does not completely separate the first shell portion 20 from the second shell portion 21. In other words, in a part of the region, the first shell portion 20 and the second shell portion 21 are directly opposite to each other to define an internal space for accommodating a part of the components of the circuit breaker. In addition, between the first shell portion 20 and the partition portion 22, and between the second shell portion 21 and the partition portion 22, each defines an internal space for accommodating other components of the circuit breaker. A part of the housing 2, such as the second shell portion 21, can further be formed with a window 23 in communication with the internal spaces, through which a worker can obtain the current on-off state information of the circuit breaker 1.

[0030] Figure 3 And Figure 4The internal structure of the circuit breaker 1 is shown from two angles, in which the circuit breaker 1 is in the breaking state. As shown, inside the shell 2 with a thickness of 1P (i.e. the thickness of a conventional single-pole circuit breaker, approximately 18mm) is arranged a 2P circuit. The 2P circuit can be applied in series or separately, expanding the application range of the circuit breaker 1. Specifically, the 1P shell contains two contact groups for connecting to the 2P circuit respectively, two short-circuit tripping mechanisms, two overload tripping mechanisms, two arc extinguishing mechanisms and two sets of terminal blocks.

[0031] As shown, in the first accommodating space 201 formed between the partition portion 22 and the first shell portion 20 can be disposed the first arc extinguishing mechanism 9, the first overload tripping mechanism 8 and the first set of terminal blocks, including the first terminal block 24 and the second terminal block 25. In the second accommodating space 202 formed between the partition portion 22 and the second shell portion 21 can be disposed the second arc extinguishing mechanism 90, the second overload tripping mechanism 80 and the second set of terminal blocks, including the third terminal block 26 and the fourth terminal block 27. The first arc extinguishing mechanism 9 and the second arc extinguishing mechanism 90, and the first overload tripping mechanism 8 and the second overload tripping mechanism 80, are arranged side by side along the thickness direction of the shell 2 and separated by the partition portion 22.

[0032] The handle 3, the operating mechanism 4, the two contact groups and the two short-circuit tripping mechanisms can be disposed in the space between the first shell portion 20 and the second shell portion 21. As shown, the handle 3 is pivotally mounted to the shell 2 and drivingly connected to the operating mechanism 4. For example, a pivot shaft can be extended from the inner wall of the second shell portion 21 along the thickness direction, and the handle 3 is sleeved on the pivot shaft. When the handle 3 is pivoted about the pivot shaft in the closing direction, the operating mechanism 4 can be driven to move the moving contacts of the two contact groups to approach the corresponding static contacts. When the handle 3 is pivoted about the pivot shaft in the opening direction, the operating mechanism 4 can be driven to move the moving contacts of the two contact groups away from the corresponding static contacts. The handle 3 is provided with a handle biasing member 31, such as a handle torsional spring. One end of the handle biasing member 31 abuts against the handle 3, for example, is embedded in a groove of the handle 3, and the other end abuts against the shell 2. The handle biasing member 31 can apply a biasing force to the handle 3 to rotate it in the opening direction. The two contact groups are arranged side by side along the thickness direction of the shell 2, one of which includes the first moving contact 5 and the first static contact 6, and the other of which includes the second moving contact 50 and the second static contact 60. The first arc extinguishing mechanism 9 is arranged corresponding to one contact group, and the second arc extinguishing mechanism 90 is arranged corresponding to the other contact group.

[0033] The first short-circuit opening mechanism 7 and the second short-circuit opening mechanism 70 are parallel to each other and arranged side by side in another direction perpendicular to the thickness direction of the housing 2. In the embodiment shown, they are stacked in the direction from the handle 3 to the arc extinguishing mechanisms 9, 90. In order to secure the first short-circuit opening mechanism 7 and the second short-circuit opening mechanism 70, the partition portion 22 can form a first bracket 221 and a second bracket 222 side by side in the other direction to mount the first short-circuit opening mechanism 7 and the second short-circuit opening mechanism 70. The first short-circuit opening mechanism 7 and the second short-circuit opening mechanism 70 stacked perpendicular to the thickness direction of the housing 2 can effectively reduce the overall space occupied by the 2P circuit, ensuring that the 2P circuit can be compactly arranged in a 1P-thickness housing 2.

[0034] The connection mode of each 2P circuit is as follows:

[0035] The first connection terminal 24 is connected to the first short-circuit opening mechanism 7, and the first short-circuit opening mechanism 7 is connected to the first static contact 6. The first moving contact 5 is connected to the first overload opening mechanism 8, and the first overload opening mechanism 8 is connected to the second connection terminal 25. When the first static contact 6 is engaged with the first moving contact 5, this circuit can be connected to the loop.

[0036] The third connection terminal 26 is connected to the second short-circuit opening mechanism 70, and the second short-circuit opening mechanism 70 is connected to the second static contact 60. The second moving contact 50 is connected to the second overload opening mechanism 80, and the second overload opening mechanism 80 is connected to the fourth connection terminal 27. When the second static contact 60 is engaged with the second moving contact 50, this circuit can be connected to the loop.

[0037] In the embodiment shown, the first short-circuit opening mechanism 7 and the second short-circuit opening mechanism 70 can each be selected as an electromagnetic tripping mechanism. The electromagnetic tripping mechanism includes a sleeve fixed in the housing 2, a coil surrounding the outer periphery of the sleeve, an opening lever movably mounted in the sleeve in the axial direction, an armature sleeved on one end of the opening lever in the sleeve, and a magnetic yoke sleeved on the other end of the opening lever. The armature and the opening lever form a driving fit. A return spring is in abutment between the opening lever and the armature. One end of the coil of the first short-circuit opening mechanism 7 is connected to the first connection terminal 24, and the other end of the coil of the first short-circuit opening mechanism 7 is connected to the first static contact 6. Thus, the first short-circuit opening mechanism 7 is connected between the first connection terminal 24 and the first static contact 6. Similarly, one end of the coil of the second short-circuit opening mechanism 70 is connected to the third connection terminal 26, and the other end of the coil of the second short-circuit opening mechanism 70 is connected to the second static contact 60. Thus, the second short-circuit opening mechanism 70 is connected between the third connection terminal 26 and the second static contact 60.

[0038] In one embodiment, the first overload tripping mechanism 8 and the second overload tripping mechanism 80 may each be configured with a bimetallic strip. The bimetallic strip of the first overload tripping mechanism 8 is connected between the first moving contact 5 and the second terminal 25, and the bimetallic strip of the second overload tripping mechanism 80 is connected between the second moving contact 50 and the fourth terminal 27.

[0039] Figure 5 and Figure 6 A single operating mechanism 4 shared by two contact groups is shown in detail. As shown, in the operating mechanism 4, a contact support 43 is pivotally mounted to the housing 2. For this purpose, a pivot shaft extending along the thickness direction of the housing 2 can be fixedly mounted on the inner wall of the housing 2, and the contact support 43 forms a first support arm with an inner hole. By passing the pivot shaft through the inner hole of the first support arm, the contact support 43 can be sleeved on the pivot shaft. Thus, the contact support 43 can rotate about the pivot shaft, but cannot move axially or radially relative to the pivot shaft. The end of the contact support 43 extending toward the window 23 of the housing 2 can be provided with a pin, and the open / close indicator 44 forms a groove, into which the pin of the contact support 43 can be inserted and moved along the groove. The indicator 44 is also sleeved on the pivot shaft extending along the thickness direction of the inner wall of the housing 2 and can rotate about the pivot shaft. The open and close indicators are arranged side by side on the surface of the indicator 44 close to the window 23. As the contact support 43 rotates, the driving indicator 44 pivots, causing one of the open and closed indicators to align with the window 23, transmitting the open / closed status information of the circuit breaker 1 to the outside. The open and closed indicators can be carried by any suitable information carrier. For example, in one embodiment, the open and closed indicators are coated with different colors, with the open indicator using a green coating and the closed indicator using a red coating. In another embodiment, the open and closed indicators are printed with the words "Open" and "Closed," or "OFF" and "ON," respectively.

[0040] The latch 41 is pivotally connected to the contact support 43. In the illustrated embodiment, a pin passes through the latch 41 and the contact support 43, thereby rotatably mounting the two together. A connecting rod 32 connects the latch 41 to the handle 3, wherein the connecting rod 32 is connected to the latch 41 at a position spaced apart from the pin. Thus, pivoting of the handle 3 can cause the latch 41 to move along with it via the connecting rod 32, thereby causing the contact support 43 to rotate.

[0041] The trip member 42 is pivotally connected to the contact support 43. In the illustrated embodiment, the trip member 42 is sleeved on a first support arm of the contact support 43, so as to be rotatable about the first support arm. Here, the pivot axis of the trip member 42 is coincident with the contact support 43. In other embodiments, the first support arm can be omitted, and the trip member 42 and the contact support 42 can be directly sleeved on a common pivot shaft. The trip member 42 is provided with a trip member biasing member 421, such as a trip member torsion spring. One end of the trip member biasing member 421 abuts against the contact support 43, for example, is inserted into a slot hole of the contact support 43, and the other end of the trip member biasing member 421 abuts against the trip member 42. Thus, the trip member biasing member 421 applies a biasing force to the trip member 42 towards the latch 41. In order to install the trip member biasing member 421, the contact support 43 can be formed with a second support arm extending along the thickness of the housing, and the trip member biasing member 421, such as a torsion spring, is sleeved on the second support arm, and one end or one torsion spring leg of the trip member biasing member 421 can be inserted into a slot hole of the second support arm. Generally, under the force of the trip member biasing member 421, the trip member 42 and the latch 41 are always in abutment, that is, in a locked or latched state. Once a preset current condition occurs in the circuit, for example, an overload or a short circuit, the corresponding tripping mechanism will apply an external force to the trip member 42 in the opposite direction of the biasing force of the trip member biasing member 421, so as to cause the trip member 42 and the latch 41 to be unlocked.

[0042] A contact support biasing member (not shown in the figure) is further provided between the contact support 43 and the housing 2. The contact support biasing member can be configured as a compression spring abutting between the contact support 43 and the housing 2 on a side of the contact support 43 facing away from the trip member 42. The contact support 43 and the housing 2 can each be formed with a structure for installing the compression spring, for example, the contact support 43 can be formed with a boss, and the inner wall of the housing 2 can extend with a bracket. One end of the spring is sleeved on the boss, and the other end abuts against the bracket. Thus, the contact support biasing member applies a biasing force to the contact support 43 to pivot in the tripping direction. The first moving contact 5 and the second moving contact 50 are disposed on opposite sides of the contact support 43 along the thickness direction of the housing 2, and can be driven away from the first stationary contact 6 and the second stationary contact 60 to achieve tripping. In other embodiments, the contact support biasing member can be replaced by any suitable spring configuration, for example, a tension spring connected between the contact support and the housing, which can also apply a biasing force to the contact support to rotate in the direction away from the first stationary contact and the second stationary contact. In another embodiment, the contact support biasing member can be configured as a torsion spring abutting between the contact support and the housing, such as being sleeved on a protrusion formed by the contact support or the housing, wherein one leg of the torsion spring abuts against the inner wall of the housing, and the other leg of the torsion spring abuts against the contact support, which can also apply a biasing force to the contact support to rotate in the direction away from the first stationary contact and the second stationary contact.

[0043] To mount the first moving contact 5 and the second moving contact 50, the contact support 43 can be formed with a third support arm and a fourth support arm extending along the housing thickness on opposite sides, respectively. The first moving contact 5 is rotatably sleeved on the third support arm, and the second moving contact 50 is rotatably sleeved on the fourth support arm. The third support arm and the fourth support arm are spaced apart from the first support arm and the second support arm as described above. In one embodiment, the third support arm and the fourth support arm are coaxial. In other embodiments, the third support arm and the fourth support arm can be axially staggered with respect to each other. The first moving contact 5 is provided with a first moving contact biasing member 51. As shown, the first moving contact biasing member 51 can be configured as a torsion spring sleeved on the third support arm, wherein one leg of the torsion spring abuts against the contact support 43 from the side of the contact support 43 facing away from the release 42, and the other leg of the torsion spring abuts against the first moving contact 5 from the side of the first moving contact 5 facing away from the first stationary contact 6. Thus, the first moving contact biasing member 51 applies a biasing force to the first moving contact 5 to rotate towards the first stationary contact. Similarly, the second moving contact 50 is provided with a second moving contact biasing member 501. The second moving contact biasing member 501 can be configured as a torsion spring sleeved on the fourth support arm, wherein one leg of the torsion spring abuts against the contact support 43 from the side of the contact support 43 facing away from the release 42, and the other leg of the torsion spring abuts against the second moving contact 50 from the side of the second moving contact 50 facing away from the second stationary contact 60. Thus, the second moving contact biasing member 501 applies a biasing force to the second moving contact 50 to rotate towards the second stationary contact.

[0044] The opening and closing operations of the circuit breaker 1 will be described in detail below.

[0045] When manual opening is required, the handle 3 is rotated in the opening direction, during which the handle biasing member 31 releases energy. The rotation of the handle 3 pulls the lock catch 41 and the contact support 43 together through the connecting rod 32. The rotation of the contact support 43 simultaneously moves the first moving contact 5 and the second moving contact 50 away from the first stationary contact 6 and the second stationary contact 60. The contact support biasing member releases energy during this period. When the opening is in place and the contact support 43 stops moving, the opening indication of the indicator 44 is aligned with the window 23 of the housing 2. During manual opening, the release 42 is always locked with the lock catch 41 under the action of the release biasing member 421.

[0046] When manual closing is required, handle 3 is turned in the closing direction, during which handle bias 31 is compressed and stored. The turning of handle 3 pushes lock catch 41 and contact support 43 to move together through link 32. During the turning of contact support 43, contact support bias is compressed and stored. The turning of contact support 43 also brings first moving contact 5 and second moving contact 50 to move synchronously, respectively approaching and engaging to first stationary contact 6 and second stationary contact. When the closing is in place and contact support 43 stops moving, closing indication of indicator 44 is aligned with window 23 of housing 2. During manual closing, trip member 42 is always in contact with lock catch 41 due to the bias of trip member bias 421, and the bias of contact support bias is not enough to rotate contact support in the opening direction, thus the breaker 1 is prohibited from opening. First moving contact 5 and second moving contact 50 are respectively stably pressed to first stationary contact 6 and second stationary contact 60 due to the existence of first contact bias 51 and second contact bias 52, preventing the occurrence of play.

[0047] Once a short circuit occurs in any of the 2P lines, the electromagnetic force generated by the short circuit current will drive the armature of the short circuit opening mechanism in the corresponding line to move and approach the magnetic yoke, thus causing the opening lever to move and hit trip member 42, causing trip member 42 to rotate and separate from lock catch 41 against the bias of trip member bias 421. At this time, the contact support bias can release energy and drive contact support 43 to move in the opening direction, bringing first moving contact 5 and second moving contact 50 to move synchronously, respectively away from first stationary contact 6 and second stationary contact 60, achieving the opening of breaker 1.

[0048] If current overload occurs in any of the 2P lines, the bimetallic strip of the overload opening mechanism in the corresponding cable will be deformed by heat, driving trip member 42 to rotate and separate from lock catch 41 against the bias of trip member bias 421. At this time, the contact support bias can release energy and drive contact support 43 to move in the opening direction, bringing first moving contact 5 and second moving contact 50 to move synchronously, respectively away from first stationary contact 6 and second stationary contact 60, achieving the opening of breaker 1.

[0049] It should be understood that although the present specification is described in terms of various embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

[0050] The above merely illustrates the specific implementation of the present application, and is not intended to limit the scope of the present application. Any equivalent changes, modifications and combinations made by any person skilled in the art without departing from the concept and principles of the present application shall fall within the scope of the present application.

Claims

1. A circuit breaker characterized by, The circuit breaker comprises: a housing; a handle pivotally mounted to the housing; two contact assemblies spaced apart within the housing and each comprising a stationary contact and a movable contact movable relative to the stationary contact; an operating mechanism connected between the handle and the two contact assemblies and shared by the two contact assemblies, the operating mechanism having a locked state and an unlocked state, in the locked state, the operating mechanism is drivable by the handle to hold the movable contact of each of the two contact assemblies in engagement with the stationary contact and is also drivable by the handle to separate the movable contact of each of the two contact assemblies from the stationary contact; two short-circuit tripping mechanisms respectively connected to the stationary contact of the two contact assemblies within the housing, the two short-circuit tripping mechanisms are configured to each drive the operating mechanism to the unlocked state in response to a first preset current condition to allow the stationary contact to separate from the movable contact.

2. The circuit breaker of claim 1, wherein, The circuit breaker comprises two overload tripping mechanisms spaced apart within the housing, the two overload tripping mechanisms are respectively connected to the movable contact of the two contact assemblies and are configured to each drive the operating mechanism to the unlocked state in response to a second preset current condition to allow the stationary contact to separate from the movable contact.

3. The circuit breaker of claim 1, wherein, The circuit breaker comprises two arc extinguishing mechanisms spaced apart within the housing corresponding to the two contact assemblies.

4. The circuit breaker of claim 1, wherein, The circuit breaker comprises two sets of terminal blocks spaced apart within the housing and respectively connected to the two contact assemblies, wherein one terminal block of each set of terminal blocks is connected to the movable contact of the corresponding contact assembly and the other terminal block is connected to the stationary contact of the corresponding contact assembly.

5. The circuit breaker of any one of claims 1 to 4, wherein, The housing has a thickness of 1P, the two short-circuit tripping mechanisms are parallel to each other and are spaced apart in another direction perpendicular to the thickness direction.

6. The circuit breaker of any one of claims 1 to 4, wherein, The housing comprises a first housing part and a second housing part detachably connected, and a partition part clamped between the first housing part and the second housing part, the partition part forms a support for supporting the two short-circuit tripping mechanisms, and the partition part and the first housing part and the second housing part respectively form a containing space for containing the arc extinguishing mechanism.

7. The circuit breaker of any one of claims 1 to 4, wherein, The operating mechanism comprises: a contact support pivotally mounted to the housing; a latch pivotally connected to the contact support and connected to the handle; a trip member pivotally connected to the contact support, the trip member is capable of being pressed against the latch to place the operating mechanism in the locked state and is capable of being disengaged from the latch to place the operating mechanism in the unlocked state.

8. The circuit breaker of claim 7, wherein, The operating mechanism comprises a trip member biasing member, one end of the trip member biasing member abuts against the contact support and the other end abuts against the trip member and applies a biasing force to the trip member towards the latch.

9. The circuit breaker of claim 7, wherein, A movable contact biasing member is provided for each movable contact, one end of the movable contact biasing member abuts against the contact support and the other end abuts against the movable contact and applies a biasing force to the movable contact towards the stationary contact.

10. The circuit breaker of claim 7, wherein, A contact support biasing member is pressed between the contact support and the housing, the contact support biasing member applies a biasing force to the contact support away from the stationary contact.

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