Miniature residual-current circuit breaker

Abstract

The invention discloses a small residual-current circuit breaker, which comprises a shell, an operating mechanism, a residual-current release and a transmission rod, when the electric leakage tripper is actuated, an ejector rod of the electric leakage tripper pushes the transmission rod, so that the transmission rod rotates from a reset position to an actuating position, and the transmission rod pushes the mechanism assembly to unlock in the rotating process, so that the operation mechanism is converted from closing to tripping. The rotation center of the handle and the rotation center of the mechanism assembly are both located in the first space, and the handle is located between the electric leakage release and the mechanism assembly in the length direction; the handle is provided with a reset part, and after the electric leakage release is actuated, the reset part impacts the transmission rod to enable the transmission rod to return to the reset position from the actuation position in the process that the handle is converted from closing to tripping; the position relation of the electric leakage tripper, the operating mechanism and the like is rearranged, so that the product structure is more compact, and the size of the circuit breaker in the length direction is reduced.

Description

Technical Field

[0001] The present application relates to the field of low-voltage electrical appliances, and in particular to a small leakage circuit breaker. Background Art

[0002] In the field of small leakage circuit breakers, there are usually two design forms.

[0003] In the first way, the leakage trip module is assembled on one side of the small circuit breaker (air switch) as an accessory. The overall length of the circuit breaker of this structure is basically close to the size of an ordinary small circuit breaker (air switch), but for the entire leakage circuit breaker, its structure is not streamlined, after all, the leakage trip module also requires an independent module housing. For example, the controller of an electronic leakage circuit breaker disclosed in CN107248487A, whose leakage trip mechanism is separately arranged in a housing (that is, the controller mentioned in this patent), adopts this method.

[0004] In the second method, the leakage tripping mechanism is directly built into the small circuit breaker (air switch). In this method, at least a lot of structures can be simplified and saved. For example, the module housing of the leakage tripping module in the first method can be saved. However, in this existing method, in order to realize the connection between the leakage tripping device and the circuit breaker operating mechanism, a tripping rod in the form of linear sliding (the sliding direction is the same as the length direction of the circuit breaker) will be added. In order to allow the tripping rod to have enough movement distance, the leakage tripping device and the electromagnetic tripping device (short-circuit protection tripping device) need to be misaligned in the length direction. At the same time, after the leakage tripping device of this mechanism is actuated, if the tripping rod wants to be reset, it will need to rely on the next closing operation to reset it, which will inevitably cause the lock to bear too much other forces (ideally, when closing the switch, the lock is only subjected to the lock-related forces as much as possible, and other irrelevant forces are avoided as much as possible), which is not conducive to the closing operation of the circuit breaker and is easy to slip. Such a structure virtually increases the overall length of the circuit breaker too much, and is prone to slippage. For example, the structure disclosed in CN106783436A adopts such a solution.

[0005] Therefore, it is necessary to more reasonably design a structure that can directly set the leakage releaser inside the small circuit breaker (air switch) and reduce the length of the circuit breaker as much as possible. Summary of the invention

[0006] In view of this, the purpose of this application is to overcome the deficiencies in the prior art and to provide a small leakage circuit breaker.

[0007] The present application provides a miniature residual current circuit breaker, which includes a housing comprising a first space and a second space. In the height direction, the first space is located above the second space, and the volume of the second space is larger than that of the first space; an operating mechanism including a handle, a connecting rod and a mechanism assembly, wherein the handle and the mechanism assembly are rotatably arranged relative to the housing, and the handle is connected to the mechanism assembly through the connecting rod; a short-circuit protection release arranged in the second space for realizing short-circuit protection; a residual current release arranged in the first space for realizing residual current protection; a transmission rod rotatably arranged with the housing and having a rotation center located in the second space; the transmission rod has a reset position and an actuating position; when the residual current release is actuated, the ejector rod of the residual current release pushes the transmission rod, causing the transmission rod to rotate from the reset position to the actuating position, and during the rotation, the transmission rod pushes the mechanism assembly to unlock, so that the operating mechanism changes from closing to tripping; the rotation centers of the handle and the mechanism assembly are both located in the first space, and in the length direction, the handle is located between the residual current release and the mechanism assembly; the handle has a reset portion, and after the residual current release is actuated, during the process of the handle changing from closing to tripping, the reset portion impacts the transmission rod to make it return from the actuating position to the reset position.

[0008] First, this structure overcomes the technical prejudice in the art (the technical prejudice in the art is that the circuit breaker housing is a "convex"-shaped housing. When the residual current release is arranged inside the circuit breaker housing, it is necessary to increase the ejector rod of the residual current release with linear motion. Therefore, the residual current release can only be misaligned with the instantaneous release in the length direction, and the residual current release cannot be arranged in the upper half of the "convex"-shaped housing because the space is definitely not enough). Instead, a rotary transmission rod is used, and the rotation centers of the residual current release, the handle, the mechanism assembly and the transmission rod are rearranged, so that the residual current release can be arranged in the upper half of the "convex"-shaped housing (that is, in the first space), effectively controlling the overall length dimension of the circuit breaker and making the overall structure more compact.

[0009] Second, the arrangement of the transmission rod and the reset portion on the handle enables the reset of the transmission rod to be achieved during the process of the handle changing from closing to tripping every time the residual current release is actuated. In this way, it is not necessary to drive the transmission rod to reset additionally during the next closing operation (in the structure disclosed in the prior art, its tripping rod must rely on the impact when the latch returns, that is, the tripping rod is reset when driving the handle to perform the closing operation; but as is well known, during the closing operation of the circuit breaker, it is a process of re-locking the latch, and the force on the latch is preferably as simple as possible. If the latch is additionally required to bear the reset of the tripping rod, it is very likely that the latch cannot be re-locked, resulting in a slipping phenomenon), making the motion relationship of the entire operating mechanism more reasonable and stable.

[0010] In some embodiments of the present application, the housing includes a first half-shell and a second half-shell, and the first half-shell and the second half-shell are fastened by a fastening assembly; the first half-shell includes a first narrow portion and a first wide portion, and the second half-shell includes a second narrow portion and a second wide portion; the dimensions of the first narrow portion in the height direction and the length direction are both smaller than those of the first wide portion, and the dimensions of the second narrow portion in the height direction and the length direction are both smaller than those of the second wide portion; the first space is jointly formed by the first narrow portion and the second narrow portion, and the second space is jointly formed by the first wide portion and the second wide portion.

[0011] Adopting such a structure makes the structure of the entire circuit breaker more compact.

[0012] In some embodiments of the present application, the transmission rod and the mechanism assembly are both rotatably connected to the first half-shell; in the width direction, the transmission rod is located on one side of the mechanism assembly and is closer to the first half-shell than the mechanism assembly; the mechanism assembly extends towards the direction where the first half-shell is located with a driven portion, and the driven portion is used to cooperate with the impact portion to realize the pushing of the mechanism assembly by the impact portion.

[0013] Such a structure is also to make the combination of the transmission rod and the mechanism assembly more tight and compact, and make full use of the space inside the circuit breaker.

[0014] In some embodiments of the present application, the transmission rod further includes a pivot portion, an impact portion, a bending portion, and a trigger portion connected in sequence. The pivot portion is used to form a rotational setting with the housing, the impact portion is used to cooperate with the mechanism assembly, the trigger portion is used to cooperate with the leakage tripping device, and the bending portion forms an opening structure; when the leakage tripping device is actuated, the ejector rod of the leakage tripping device pushes the trigger portion to make the transmission rod rotate, causing the bending portion to move in a direction away from the rotation center of the mechanism assembly, but the rotation center of the mechanism assembly is always in the opening structure.

[0015] With such a design of the transmission rod, by using the opening structure design of the bending portion, the rotation center of the mechanism assembly is in the opening structure, which is beneficial to making the integration of the transmission rod and the mechanism assembly more compact, beneficial to saving the internal space of the product, reducing the volume of the entire circuit breaker, and is also more applicable to the situation where the leakage tripping device is arranged in the first space as described above.

[0016] In some embodiments of the present application, the bending portion includes a first bent arm and a second bent arm, and the rotation center of the mechanism assembly is close to the connection portion of the first bent arm and the second bent arm; the impact portion is connected to one end of the first bent arm, and the trigger portion is located at one end of the second bent arm; the end of the trigger portion close to the leakage tripping device is a trigger surface for the leakage tripping device to drive; the trigger portion has a reset surface adjacent to the trigger surface for returning the transmission rod to the reset position under the action of the reset portion.

[0017] With such a structural arrangement, the triggering part is the force-receiving end that causes the transmission rod to move towards the actuating position, and also the force-receiving end that causes the transmission rod to move towards the reset position. Such a structure is more likely to achieve the reset of the handle and the actuation of the leakage circuit breaker, and is also conducive to making the entire structure more compact.

[0018] In some embodiments of the present application, for Structure 1, the triggering part protrudes from the first surface of the second bent arm, and a first avoidance groove is provided on the reset part; during the rotation of the transmission rod towards the reset position, there is an intersection between the movement trajectory of the triggering part and the movement trajectory of the reset part, so it can return to the reset position under the action of the reset part; after the transmission rod is in the reset position, the triggering part does not interfere with the reset part through the first avoidance groove, so as to ensure that the next triggering of the triggering part and the closing operation of the operating mechanism can be completed.

[0019] The design of the first avoidance groove is conducive to the handle timely avoiding the triggering part without affecting the normal operation of the handle. At the same time, it can make the handle closer to the transmission rod, making the structure more compact and conducive to reducing the volume of the entire product (if there is no avoidance groove, the handle and the transmission rod need to be set far apart, which will virtually increase the volume of the first space and is not conducive to the compactness and miniaturization of the product).

[0020] In some embodiments of the present application, it further includes Structure 2, where the triggering part protrudes from the first surface of the second bent arm, so that a first avoidance space is formed on one side of the transmission rod by the triggering part, and the first avoidance space is used to avoid part of the movement of the reset part.

[0021] Similarly, the design of the first avoidance space is conducive to avoiding part of the movement of the reset part of the handle (here, part of the movement refers to the movement of the reset part following the handle during normal closing and opening), and it will also enable the handle to be set closer to the transmission rod, making the two more compact and reducing the volume of the entire product (if there is no avoidance space, the space jointly occupied by the handle and the transmission rod will virtually increase, that is, the volume of the first space needs to be increased, which is not conducive to the compactness and miniaturization of the product).

[0022] In some embodiments of the present application, the handle includes a first handle and a second handle. The first handle and the second handle are independently formed, but are rotatably arranged around the same axis and are in transmission connection with each other; a part of the first handle extends out of the housing for the user to operate, a connecting rod is connected between the first handle and the mechanism assembly, and the reset part is arranged on the second handle.

[0023] The separate and concentric arrangement of the first handle and the second handle, and then the two form a transmission connection, which is beneficial to the molding of the product and can also make the first handle more versatile (the existing handle structure can be directly borrowed). Or when it is no longer used in the leakage circuit breaker and the second handle is not installed, this first handle can also be applied to the air switch (miniature circuit breaker).

[0024] In some embodiments of the present application, it further includes a moving contact and a static contact. The moving contact is rotatably arranged on the mechanism assembly and moves with the mechanism assembly; there is an unlocking boss on the mechanism assembly, and the unlocking boss is located on the side of the moving contact away from the static contact. Under the action of the electric repulsive force, the moving contact rotates and impacts the unlocking boss to accelerate the unlocking of the mechanism assembly.

[0025] With this structure, by setting the unlocking boss on the side of the moving contact away from the static contact, in the case of an extremely large fault current, an electric repulsive force will be generated between the moving and static contacts, and the electric repulsive force will also be used to accelerate the tripping of the operating mechanism.

[0026] In some embodiments of the present application, the handle includes a main body portion and a handle portion. A first locking hole is provided on the connecting portion of the handle portion for connecting with the main body portion, and a second locking hole is provided on the housing. When the operating mechanism is in the closing or opening position, the first locking hole communicates with the second locking hole for the user to hang a lock.

[0027] With this structure, compared with the prior art (the first locking hole in the prior art is provided on the main body portion), setting the first locking hole on the connecting portion of the handle portion and the main body portion will make the handle structure more beautiful and is also more conducive to the user to hang a lock.

[0028] In some embodiments of the present application, an arc guide plate, a bimetal sheet, a first wiring terminal, and a first terminal plate are further provided in the housing; the arc guide plate, the bimetal sheet, the first wiring terminal, and the first terminal plate are all arranged inside the housing; the bimetal sheet includes a first flat portion, a bending portion, and a second flat portion. The first flat portion and the second flat portion are arranged in a dislocation manner in the length direction and are connected by the bending portion; the first flat portion is fixed to the arc guide plate by riveting or welding, and the second flat portion is used to cooperate with the mechanism assembly to achieve overload protection; the angle between the first flat portion and the second flat portion is an included angle A, and 150° ≤ A ≤ 180°; in the height direction, the bimetal sheet is arranged higher than the first terminal plate.

[0029] With this structure, the position of the bimetal sheet is raised (in the prior art, the bimetal sheet is lower than the terminal and the first terminal board), and at the same time, the bimetal sheet is bent (the bimetal sheet in the prior art is just a flat plate). This not only ensures that the bimetal sheet has sufficient length (the total length of the bimetal sheet itself, rather than the length in the length direction) to ensure the performance of overload protection, but also makes the internal structure of the circuit breaker more compact, and the space below the bimetal sheet can be saved to accommodate other components.

[0030] In some embodiments of the present application, the mechanism assembly is one of the following structures. Structure One: The mechanism assembly includes a contact support, a main spring, a latch, and a latch return spring; the contact support is rotatably connected to the housing, and the main spring is used to connect between the contact support and the housing; the latch is rotatably arranged on the contact support, and the latch and the contact support jointly form a mating groove; the first end of the connecting rod is connected to the handle, and the second end of the connecting rod extends into the mating groove; the mating groove includes a locking section and an unlocking section; during the process of driving the handle to change the operating mechanism from the tripped state to the closed state, due to the relative movement between the contact support and the latch, the size of the locking section is smaller than the diameter of the second end, so that the second end abuts against the locking section, making the operating mechanism finally remain in the closed state; the unlocking of the mechanism assembly means that the latch is triggered, resulting in the size of the locking section being larger than the diameter of the second end of the connecting rod, and the second end of the connecting rod slides into the unlocking section. During this process, under the action of the main spring, the operating mechanism changes from the closed state to the tripped state; the latch return spring provides a biasing force for the latch to reset the latch.

[0031] As a form of the operating mechanism, this is a form without a buckle, which can effectively realize the tripping operation and closing operation of the circuit breaker, and the structure is very simple.

[0032] Structure Two: The mechanism assembly includes a contact support, a main spring, a buckle, a latch, and a latch return spring; the contact support is rotatably connected to the housing, and the main spring is used to connect between the contact support and the housing; the buckle and the latch are both rotatably arranged on the contact support; the connecting rod is connected between the handle and the buckle, the buckle is provided with a first engaging portion, and the latch is provided with a second engaging portion; during the process of driving the handle to change the operating mechanism from the tripped state to the closed state, the first engaging portion and the second engaging portion form a lock, making the operating mechanism finally remain in the closed state; the unlocking of the mechanism assembly means that the lock between the latch and the buckle is released, and under the action of the main spring, the operating mechanism changes from the closed state to the tripped state; the latch return spring provides a biasing force for the latch to reset the latch.

[0033] As another form of the operating mechanism, this is a form with a buckle, which can effectively realize the tripping operation and closing operation of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0035] Figure 1 Shows a perspective view of the miniature circuit breaker according to the embodiment of the present application; Figure 2 Shows an internal schematic diagram of the miniature circuit breaker according to the embodiment of the present application; Figure 3 Shows a schematic diagram of the handle in the miniature circuit breaker according to the embodiment of the present application; Figure 4 Shows an exploded schematic diagram of the first handle and the second handle in the miniature circuit breaker according to the embodiment of the present application; Figure 5 Shows a schematic diagram of the transmission rod in the miniature circuit breaker according to the embodiment of the present application; Figure 6 Shows a schematic diagram of the mechanism assembly in the miniature circuit breaker according to the embodiment of the present application; Figure 7 Shows a positional relationship diagram of the leakage circuit breaker, the transmission rod, and the operating mechanism when the miniature circuit breaker according to the embodiment of the present application is in the closed state; Figure 8 Shows a positional relationship diagram of the leakage circuit breaker, the transmission rod, and the operating mechanism when the miniature circuit breaker according to the embodiment of the present application is in the tripped state (when the leakage circuit breaker is just actuated); Figure 9 Shows a positional relationship diagram of the leakage circuit breaker, the transmission rod, and the operating mechanism when the miniature circuit breaker according to the embodiment of the present application is in the tripped state (during the process of the handle turning to the off position, the reset part urges the transmission rod to reset); Figure 10 Shows a positional relationship diagram of the leakage circuit breaker, the transmission rod, and the operating mechanism when the miniature circuit breaker according to the embodiment of the present application is in the off state; Figure 11 Shows a schematic diagram of the arc extinguishing chamber and the arc guiding plate of the miniature circuit breaker according to the embodiment of the present application; Figure 12 Shows a schematic diagram of the arc guiding plate of the miniature circuit breaker according to the embodiment of the present application; Figure 13 Shows a schematic diagram of the bimetallic strip of the miniature circuit breaker according to the embodiment of the present application. Detailed implementation manners

[0036] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present application and should not be construed as limiting the present application.

[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

[0038] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0039] In the present application, unless otherwise clearly specified and defined, the terms "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0040] In the present application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature. Embodiment

[0041] As Figures 1-13As shown in the figure, an embodiment of the present application is a small leakage circuit breaker, including a housing 100, an operating mechanism 200, a moving contact 300, a static contact 350, an arc extinguishing chamber 500, a first terminal board 700, a first connection terminal 750, an arc guiding plate 400, a second terminal board, a second connection terminal, a short - circuit protection release 600, a leakage protection release 800, an overload protection release (bimetal 900), etc.

[0042] As Figure 1 shown, the housing 100 includes a first half - shell 101 and a second half - shell 102, and the first half - shell 101 and the second half - shell 102 are fastened by a fastening assembly. Here, the fastening assembly is in the form of multiple rivets combined with a buckle, that is, after the first housing 100 and the second housing 100 are connected by a buckle, they are further fastened by multiple rivets. Of course, in addition to this, it is also possible to only use a buckle structure or only use a structure of multiple rivets for fastening, or even a structure of multiple screws for fastening.

[0043] As Figure 1 shown, for the first half - shell 101, it includes a first narrow part 101a and a first wide part 101b, and the dimensions of the first narrow part 101a in the height direction H and the length direction L are both smaller than those of the first wide part 101b.

[0044] As Figure 1 shown, for the second half - shell 102, it includes a second narrow part 102a and a second wide part 102b, and the dimensions of the second narrow part 102a in the height direction H and the length direction L are both smaller than those of the second wide part 102b.

[0045] As Figures 1-2 shown, the first narrow part 101a and the second narrow part 102a together form a first space S1, and the first wide part 101b and the second wide part 102b together form a second space S2. Therefore, the second space S2 (volume) is larger than the first space S1 (volume).

[0046] As Figure 6 shown, the operating mechanism 200 includes a handle 201, a connecting rod 202, and a mechanism assembly. The handle 201 and the mechanism assembly are both rotatably arranged relative to the housing 100. Here, a mechanism assembly in a non - buckle form is adopted, that is, the mechanism assembly includes a contact support 203, a main spring, a latch 204, and a latch return spring.

[0047] As Figure 6 shown, the moving contact 300 is rotatably arranged on the contact support 203, the contact support 203 is rotatably connected to the housing 100, and the main spring is used to connect between the contact support 203 and the housing 100.

[0048] As Figure 6As shown, the latch 204 is rotatably arranged on the contact support 203, and the latch 204 and the contact support 203 jointly form a mating groove 205; the first end of the connecting rod 202 is connected to the handle 201, and the second end of the connecting rod 202 extends into the mating groove 205. The mating groove 205 includes a locking section 205a and an unlocking section 205b. During the process of driving the handle 201 to change the operating mechanism 200 from opening to closing, due to the relative movement between the contact support 203 and the latch 204 (the second end slides from the unlocking section 205b into the locking section 205a, and the latch 204 rotates due to the action of the latch return spring), the size of the locking section 205a is smaller than the diameter of the second end, so that the second end abuts against the locking section 205a until the moving and static contacts 350 are closed, and finally the operating mechanism 200 remains in the closed state.

[0049] When the latch 204 is triggered (this triggering of the latch 204 is also called the unlocking of the mechanism assembly, and the reasons for unlocking can be that the handle 201 rotates in the opening direction, causing the second end to impact the latch 204 and rotate; or it can be caused by the actuation of the overload protection release, the leakage protection release 800, and the instantaneous protection release, resulting in the rotation of the latch 204), the size of the locking section 205a is larger than the diameter of the second end of the connecting rod 202, and the second end of the connecting rod 202 slides into the unlocking section 205b. During this process, under the action of the main spring, the operating mechanism 200 changes from closing to tripping.

[0050] Of course, the operating mechanism 200 can also be changed to a form with a buckle. The structure of the operating mechanism 200 with a buckle is that the mechanism assembly includes a contact support 203, a main spring, a buckle, a latch 204, and a latch return spring; the contact support 203 is rotatably connected to the housing 100, and the main spring is used to connect between the contact support 203 and the housing 100. The buckle and the latch 204 are both rotatably arranged on the contact support 203; the connecting rod 202 is connected between the handle 201 and the buckle, and a first engaging portion is provided on the buckle, and a second engaging portion is provided on the latch 204. During the process of driving the handle 201 to change the operating mechanism 200 from opening to closing, the first engaging portion and the second engaging portion are locked, so that the operating mechanism 200 finally remains in the closed state.

[0051] When the latch 204 is triggered (this triggering of the latch 204 is also called the unlocking of the mechanism assembly, and the reasons for unlocking can be that the handle 201 rotates in the opening direction, causing the buckle to rotate; or it can be caused by the actuation of the overload protection release, the leakage protection release 800, and the instantaneous protection release, resulting in the rotation of the latch 204), the first engaging portion and the second engaging portion are unlocked. During this process, under the action of the main spring, the operating mechanism 200 changes from closing to tripping.

[0052] As Figure 11As shown, the arc extinguishing chamber 500 uses fifteen arc extinguishing grid plates to extinguish the arc generated when the moving and static contacts 350 are separated.

[0053] As Figure 2 shown, the short-circuit protection release 600 is arranged in the second space S2 (specifically, at a position in the second space S2 close to the first space S1, and part of the solenoid will occupy a part of the first space S1). It is actuated due to the short circuit of the main line. After actuation, it will push the latch 204 to achieve the tripping of the operating mechanism 200. Here, the actual working principle of the short-circuit protection release 600 is the working principle of an electromagnet. Although the scheme adopted here is a solenoid type. However, in addition, it can also be a clapper type. No matter which method, it already belongs to the conventional technical means in this field and will not be elaborated here.

[0054] As Figure 2 、 Figure 13 shown, the overload protection release is actually a bimetal 900 arranged in the second space S2. The bimetal 900 is a component of the main line conductor. One end of the bimetal 900 cooperates with the bimetal pull rod 901 on the latch 204. When the main line is overloaded, the bimetal 900 bends and pulls the bimetal pull rod 901, causing the latch 204 to unlock and achieving the tripping of the operating mechanism 200. The principle of this bimetal 900 tripping also already belongs to the conventional technical means in this field and will not be elaborated here.

[0055] As Figure 2 shown, the leakage protection release 800 is arranged in the first space S1 to achieve leakage protection. Here, the actuation of the leakage protection release 800 means that after receiving the leakage protection signal, the ejector rod 801 of the leakage protection release 800 will extend. And the source of this leakage protection signal can be given by the zero-sequence current transformer and the leakage protection circuit inside the circuit breaker, or it can be given by the upper computer or an external module. No matter which way it is given, it already belongs to the conventional means in this field and will not be elaborated here.

[0056] As Figure 2 、 Figure 5 shown, the transmission rod 850 is rotatably arranged with the housing 100, specifically rotatably arranged with the first housing 100, and the rotation center is arranged in the second space S2. The other end of the transmission rod 850 extends to the side of the leakage protection release 800 to achieve the leakage protection action. Here, the transmission rod 850 has a reset position M1 and an actuation position M2. When the leakage protection release 800 is actuated, the ejector rod 801 of the leakage protection release 800 pushes the transmission rod 850, causing the transmission rod 850 to rotate from the reset position M1 to the actuation position M2. During the rotation process, the transmission rod 850 pushes the latch 204 to unlock, so that the operating mechanism 200 changes from closing to tripping.

[0057] As Figure 3 , Figure 4 shown, the handle 201 is provided with a reset portion 201b1. When changing from closing to tripping, the reset portion 201b1 of the handle 201 will strike the transmission rod 850 to make it return from the actuating position M2 to the reset position M1.

[0058] Regarding the relative arrangement relationship between such an operating mechanism 200 and the leakage circuit breaker 800, the leakage circuit breaker 800, the handle 201, the connecting rod 202, the rotation centers of the contact support 203, and the part of the contact support 203 and the latch 204 including the mating groove 205 are all located within the first space S1. Here, from the longitudinal direction L, the handle 201 is located between the leakage circuit breaker 800 and the mechanism assembly.

[0059] Adopting such a structure overcomes the technical prejudice in this field (the technical prejudice in this field is that the circuit breaker housing 100 is a "convex" - shaped housing 100. When the leakage circuit breaker 800 is arranged inside the circuit breaker housing 100, it is necessary to increase the ejector rod 801 of the linear - motion leakage circuit breaker 800. Therefore, the leakage circuit breaker 800 can only be misaligned with the instantaneous tripping device in the longitudinal direction L. Therefore, it may be arranged in the upper half of the "convex" - shaped housing 100 because the space is definitely insufficient). Instead, a rotary transmission rod 850 is used, and the rotation centers of the leakage circuit breaker 800, the handle 201, the rotation center of the mechanism assembly, and the rotation center of the transmission rod 850 are rearranged, so that the leakage circuit breaker 800 can be arranged in the upper half of the "convex" - shaped housing 100 (that is, in the first space S1), effectively controlling the overall length dimension of the circuit breaker and making the overall structure more compact.

[0060] At the same time, the arrangement of the transmission rod 850 and the reset portion 201b1 on the handle 201 enables the reset of the transmission rod 850 to be achieved during the process of the handle 201 changing from closing to tripping every time the leakage circuit breaker 800 is actuated. In this way, it is not necessary to additionally drive the transmission rod 850 to reset during the next closing operation (in the structure disclosed in the prior art, its tripping rod must rely on the impact when the latch 204 returns, that is, the tripping rod is reset when driving the handle 201 to perform the closing operation; but as is well known, during the closing operation of the circuit breaker, it is a process of re - locking the latch 204, and the force on the latch 204 is preferably as simple as possible. If the latch 204 is additionally required to bear the reset of the tripping rod, it is very likely that the latch 204 cannot be re - locked, resulting in a slipping - latch phenomenon), making the motion relationship of the entire operating mechanism 200 more reasonable and stable.

[0061] As Figure 5As shown, for the transmission rod 850, it includes a pivot portion 851, an impact portion 852, a bending portion 853, and a trigger portion 854 that are connected in sequence. The pivot portion 851 is a ring structure and is sleeved on the positioning shaft O1 of the half shell to form a rotational connection. The impact portion 852 is located near a part of the latch 204 to unlock the latch 204 by impacting this part of the latch 204. The bending portion 853 forms an opening structure 853c such that the rotation center (the first pin shaft O2) of the mechanism assembly is located in the opening structure 853c. The trigger portion 854 extends near the ejector rod 801 of the leakage circuit breaker 800 for the ejector rod 801 to trigger. Here, when the leakage circuit breaker 800 is actuated, the transmission rod 850 rotates under the action of the ejector rod 801, that is, the rotation center (the first pin shaft O2) of the mechanism assembly and the bending portion 853 generate relative movement, which is equivalent to the rotation center of the mechanism assembly "moving" away from the direction where the opening structure 853c is located.

[0062] With such a design of the transmission rod 850, by using the opening structure 853c design of the bending portion 853, the rotation center of the mechanism assembly is located in the opening structure 853c, which is beneficial to making the integration of the transmission rod 850 and the mechanism assembly more compact, conducive to saving the internal space of the product, reducing the volume of the entire circuit breaker, and is also more applicable to the situation where the leakage circuit breaker 800 is arranged in the first space S1 as described above.

[0063] As Figure 2 shown, for the handle 201, the transmission rod 850, and the mechanism assembly, they are all rotationally connected to the first half shell 101. Here, the contact support 203 is rotationally connected to the first half shell 101 with the first pin shaft O2, the transmission rod 850 is rotationally connected by sleeving the pivot portion 851 on the positioning shaft O1 of the first half shell 101, and the handle 201 is rotationally connected to the first half shell 101 and the second half shell 102 with the cylindrical structure on the main body portion 201a1. In the width direction D, the transmission rod 850 is located on one side of the mechanism assembly, that is, the transmission rod 850 is closer to the first half shell 101 compared to the contact support 203 and the latch 204. A driven portion 204a is formed by extending a part of the latch 204 towards the direction where the first half shell 101 is located, and the driven portion 204a is located near the impact portion 852 for the impact portion 852 to touch. Such a structure is also to make the transmission rod 850 and the mechanism assembly more closely and compactly combined and make full use of the internal space of the circuit breaker.

[0064] As Figure 5 、 Figures 7-10 shown, the reset portion 201b1 of the handle 201 resets the transmission rod 850 by impacting the trigger portion 854.

[0065] As Figure 5As shown, specifically, the bending portion 853 includes a first bent arm 853a and a second bent arm 853b. When the mechanism is in the closed state, the rotation center O2 of the mechanism assembly is close to the connection between the first bent arm 853a and the second bent arm 853b.

[0066] As Figure 5 shown, the impact portion 852 is connected to one end of the first bent arm 853a away from the second bent arm 853b, and the trigger portion 854 is located at one end of the second bent arm 853b away from the first bent arm 853a.

[0067] As Figure 5 shown, one end of the trigger portion 854 close to the leakage circuit breaker 800 is the trigger surface 854a, and the surface of the trigger portion 854 facing the reset portion 201b1 is the reset surface 854b. The reset surface 854b and the trigger surface 854a are two adjacent surfaces.

[0068] As Figure 5 shown, the trigger surface 854a is driven by the ejector rod 801 of the leakage circuit breaker 800, and the reset surface 854b is driven by the reset portion 201b1. With such a structural arrangement, the trigger portion 854 is both the force-receiving end that causes the transmission rod 850 to move to the actuation position M2 and the force-receiving end that causes the transmission rod 850 to move to the reset position M1. Such a structure makes it easier to achieve the reset of the handle 201 and the actuation of the leakage circuit breaker 800, and is also beneficial to making the entire structure more compact.

[0069] As Figure 3 、 Figure 4 shown, a first avoidance groove 201b2 is provided on the reset portion 201b1. The first avoidance groove 201b2 can avoid the trigger portion 854. This is to make the handle 201 and the transmission rod 850 more compactly arranged. It can not only ensure that the reset portion 201b1 can normally reset the transmission rod 850, but also ensure that there is no interference with the trigger portion 854 after reset, affecting the triggering of the trigger portion 854. And such a first avoidance groove 201b2 lays a certain foundation for the layout of the leakage circuit breaker 800 in the first space S1 and the arrangement of the transmission rod 850 in a rotational form.

[0070] As Figures 7-10 shown, the clockwise movement of the handle 201 is the closing movement, and the counterclockwise movement of the handle 201 is the tripping movement (or opening movement). The first avoidance groove 201b2 is provided on the right half of the reset portion 201b1, and the trigger portion 854 protrudes from the first surface 853b1 of the second bent arm 853b (here the first surface 853b1 is a surface of the second bent arm 853b in the width direction D).

[0071] As Figures 7-10As shown in the figure, the entire dynamic process is as follows: when the leakage trip is actuated, the transmission rod 850 moves to the actuation position M2, and the handle 201 rotates counterclockwise. At this time, there is an intersection between the movement trajectory of the trigger portion 854 and the movement trajectory of the reset portion 201b1. Therefore, under the action of the reset portion 201b1 on the reset surface 854b, the transmission rod 850 can return to the reset position M1. After the transmission rod 850 reaches the reset position M1, the handle 201 also rotates counterclockwise to the final position, and the trigger portion 854 no longer interferes with the reset portion 201b1 due to the first avoidance groove 201b2.

[0072] As Figures 7-10 shown, when the user performs the closing operation, due to the avoidance groove, the reset portion 201b1 will not touch the trigger portion 854 either. And when the trigger portion 854 is triggered next time, the reset portion 201b1 will not touch the trigger portion 854 either (of course, there will be interference between the two after triggering, and thus resetting can be achieved. This has been introduced above and will not be elaborated here).

[0073] As Figure 5 shown, for the transmission rod 850, since the trigger portion 854 protrudes from the first surface 853b1 of the second bent arm 853b, a first avoidance space 853b2 is formed on one side of the transmission rod 850 by the trigger portion 854. Such an avoidance space is also provided for avoiding part of the movement process of the reset portion 201b1.

[0074] The design of such a first avoidance space 853b2 is beneficial to avoiding the handle 201, and will also enable the handle 201 to be arranged closer to the transmission rod 850, making the two more compact and reducing the volume of the entire product (if there is no avoidance space, the handle 201 and the transmission rod need to be set far apart, which will invisibly increase the volume of the first space S1 and is not conducive to the compactness and miniaturization of the product). And such a first avoidance space 853b2 lays a certain foundation for the leakage trip 800 and the handle 201 to be jointly arranged in the first space S1.

[0075] As Figure 4 shown, there are various ways to set the handle 201 of the reset portion 201b1. As a relatively preferred way, the handle 201 is divided into a first handle 201a and a second handle 201b.

[0076] The first handle 201a here is mainly set to realize the operation of the user, that is, the connection with the mechanism component depends on the first handle 201a (that is, the connecting rod 202 is connected to the first handle 201a).

[0077] As Figure 4As shown, the second handle 201b here is designed to reset the transmission rod 850, that is, the reset part 201b1 is arranged on the second handle 201b. The first handle 201a and the second handle 201b are separately arranged, but both are rotatably arranged around the same axis, and a transmission connection is also formed between them. The transmission connection here means that a clamping connection is formed between them in the radial direction to achieve the transmission of force, that is, a transmission protrusion 201b3 is formed on the second handle 201b facing the direction of the first handle 201a, and the first handle 201a has a matching protrusion or groove, thus forming a transmission. The separate arrangement of the handle 201 can ensure that the first handle 201a is more generalized (the existing handle 201 structure can be directly borrowed).

[0078] As Figure 4 shown, for the handle 201, the first handle 201a has a main body part 201a1 and a handle part 201a2. The main body part 201a1 is used to form a rotational connection with the housing 100, and the handle part 201a2 extends out of the housing 100 for the user to operate.

[0079] As Figure 1 、 Figure 3 shown, a first locking hole 201a3 is provided at the connection part between the handle part 201a2 and the main body part 201a1. Second locking holes 100a are provided on both the first half-shell 101 and the second half-shell 102. Here, the number of the second locking holes 100a is two, one corresponding to the open position and one corresponding to the locked position. When the operating mechanism 200 is in the open position, the first locking hole 201a3 communicates with one group of the second locking holes 100a, and the user can hang a lock.

[0080] When the operating mechanism 200 is in the closed position, the first locking hole 201a3 communicates with the other group of the second locking holes 100a, and the user can also hang a lock. Compared with the prior art in which the first locking hole 201a3 is provided on the main body part 201a1, the strength of the main body part 201a1 of such a structure is higher and the structure is more beautiful.

[0081] As Figures 7-10 shown, in some extreme fault current situations, in order to facilitate the more rapid tripping of the operating mechanism 200. The latch 204 also has an unlocking boss 204b, and the unlocking boss 204b is located on the side of the moving contact 300 away from the static contact 350. The design of this unlocking boss 204b is that in extreme fault current situations, the moving contact 300 will bounce away from the direction where the static contact 350 is located under the influence of the electric repulsive force. At this time, by using the design of the unlocking boss 204b, the moving contact 300 can impact the unlocking boss 204b to accelerate the unlocking speed of the latch 204 and improve the breaking speed.

[0082] As Figure 2As shown, the first terminal 750 and the first terminal board 700 are used to connect the main circuit conductor on the side of the moving contact 300 to the external circuit. Specifically, the first terminal 750 includes a connection frame and connection screws, and the first terminal board 700 is inserted into the connection frame. A connection conductor 770 is welded on the first terminal board 700, and the connection conductor 770 is welded on the bimetal 900. Of course, as an alternative, the welding of the connection conductor 770 on the bimetal 900 can be changed to welding on the bimetal installation section 400d.

[0083] Here, the connection conductor 770 is a hard conductive sheet, but its thickness is thinner than that of the terminal board. As an alternative, the connection conductor 770 can also adopt a soft wire solution. In any case, the electrical connection between the terminal and the bimetal 900 can be completed in this way.

[0084] For the moving contact 300, it is welded to the bimetal 900 through a soft connection. In this way, the electrical connection between the moving contact 300 and the first terminal 750 can be ensured.

[0085] The second terminal and the second terminal board are used to complete the electrical connection with the static contact 350. In this way, when the two terminals are connected to the external circuit and the moving and static contacts 350 come into contact, the circuit can be switched on. Since the connection methods of components such as the second terminal, the second terminal board, and the static contact 350 belong to the common knowledge in the art, no further elaboration will be provided here.

[0086] As Figures 11-12 shown, the arc guide plate 400, as the arc guiding part of the moving contact 300, one end of the arc guide plate 400 extends below the arc extinguishing chamber 500, which is beneficial for the arc to be transferred to below the arc extinguishing chamber 500 through the arc guide plate 400.

[0087] As Figures 11-12 shown, here, the arc guide plate 400 specifically includes a horizontal section 400a, an inclined section 400b, an assembly section 400c, and a bimetal installation section 400d. Here, the horizontal section 400a is located below the arc extinguishing chamber 500, and the horizontal section 400a is connected to one end of the inclined section 400b.

[0088] As Figures 11-12 shown, the inclined section 400b is connected between the horizontal section 400a and the assembly section 400c. It is a gradually rising section, so it is called the inclined section 400b. The specific rising direction is gradually rising from the horizontal section 400a to the assembly section 400c.

[0089] As Figures 11-12As shown, a snap connection is formed between the assembly section 400c and the housing 100. Here, one of the assembly section 400c and the housing 100 is provided with a slot, and the other is provided with a fixing protrusion. The fixing protrusion is inserted into the slot to form a snap fit. As a preferred method, the slot is opened on the assembly section 400c, and the fixing protrusion is provided on the housing 100. Through such a snap connection, it can be ensured that the arc guide plate 400 is relatively stable after being installed on the outer shell.

[0090] As Figures 11-12 shown, the bimetal installation section 400d, as the name implies, is used to install the bimetal sheet 900. Here, the bimetal installation section 400d is located on one side of the assembly section 400c and is connected to the assembly section 400c.

[0091] As Figure 13 shown, specifically, the bimetal sheet 900 includes a first flat portion 900a, a bent portion 900b, and a second flat portion 900c. The first flat portion 900a and the second flat portion 900c are arranged in a staggered manner in the length direction L, and the two are connected by the bent portion 900b.

[0092] As Figure 2 shown, here, the first flat portion 900a and the bimetal installation section 400d are fixed by welding. Of course, riveting can also be used here. The second flat portion 900c is used to cooperate with the operating mechanism 200 of the circuit breaker, specifically to cooperate with the bimetal pull rod 901 on the latch 204. When an overload occurs, the bimetal sheet 900 bends and pulls the latch 204 to rotate through the bimetal pull rod 901, prompting the operating mechanism 200 to trip.

[0093] As Figures 11-12 shown, since both the first flat portion 900a and the second flat portion 900c are flat, there will be an included angle A between them. Here, the included angle A is 180°. Of course, other included angles can also be used as long as 150° ≤ A ≤ 180°.

[0094] With such a structure, the two flat portions are connected by the bent portion 900b, so that such a bimetal sheet 900 can have the same length as the bimetal sheet 900 in the prior art. While ensuring that the installation position of the bimetal sheet 900 is shifted upward compared to the prior art, it retains its original overload tripping performance (the overload tripping performance is related to the total length of the bimetal sheet 900).

[0095] After such a setting, the position of the bimetal sheet 900 is raised (in the prior art, the bimetal sheet 900 is lower than the terminal and the first terminal board 700), and at the same time, the bimetal sheet 900 is bent (the bimetal sheet 900 in the prior art is just a flat plate). This not only ensures that the bimetal sheet 900 has sufficient length (the total length of the bimetal sheet 900 itself, rather than the length in the length direction L) to ensure the performance of overload protection, but also makes the internal structure of the circuit breaker more compact, and the space below the bimetal sheet 900 can be saved to accommodate other components.

[0096] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0097] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A small leakage circuit breaker, characterized in that: include, The housing comprises a first space and a second space, wherein the first space is located above the second space in the height direction, and the volume of the second space is greater than the volume of the first space; The operating mechanism includes a handle, a connecting rod and a mechanism assembly, wherein the handle and the mechanism assembly are both rotatably arranged relative to the housing, and the handle and the mechanism assembly are connected via the connecting rod; A short-circuit protection release is arranged in the second space to achieve short-circuit protection; A leakage release is arranged in the first space to achieve leakage protection; The transmission rod is rotatably arranged with the housing and the rotation center is located in the second space; the transmission rod has a reset position and an actuation position; when the leakage release is actuated, the top rod of the leakage release pushes the transmission rod, so that the transmission rod rotates from the reset position to the actuation position, and during the rotation, the transmission rod pushes the mechanism assembly to unlock, so that the operating mechanism changes from closing to tripping; The rotation center of the handle and the rotation center of the mechanism assembly are both located in the first space, and the handle is located between the leakage releaser and the mechanism assembly in the length direction; the handle is provided with a reset part, and after the leakage releaser is actuated, when the handle is in the process of changing from closing to tripping, the reset part hits the transmission rod to return it from the actuation position to the reset position.

2. A small leakage circuit breaker according to claim 1, characterized in that: The shell includes a first half shell and a second half shell, and the first half shell and the second half shell are fastened by a fastening assembly; the first half shell includes a first narrow portion and a first wide portion, and the second half shell includes a second narrow portion and a second wide portion; the first narrow portion is smaller in height and length than the first wide portion, and the second narrow portion is smaller in height and length than the second wide portion; the first space is formed by the first narrow portion and the second narrow portion, and the second space is formed by the first wide portion and the second wide portion.

3. A small leakage circuit breaker according to claim 2, characterized in that: The transmission rod and the mechanism assembly are both rotationally connected with the first half shell; in the width direction, the transmission rod is located on one side of the mechanism assembly and is closer to the first half shell than the mechanism assembly; the mechanism assembly has a driven part extending in the direction of the first half shell, and the driven part is used to cooperate with the impact part to realize the impact part pushing the mechanism assembly.

4. A small leakage circuit breaker according to claim 1, characterized in that: The transmission rod also includes a pivoting portion, an impact portion, a bending portion and a triggering portion which are connected in sequence. The pivoting portion is used to form a rotating arrangement with the shell, the impact portion is used to cooperate with the mechanism assembly, the triggering portion is used to cooperate with the leakage releaser, and the bending portion forms an opening structure. When the leakage releaser is actuated, the top rod of the leakage releaser pushes the triggering portion to rotate the transmission rod, causing the bending portion to move in a direction away from the rotation center of the mechanism assembly, but the rotation center of the mechanism assembly is always in the opening structure.

5. A small leakage circuit breaker according to claim 4, characterized in that: The bending portion includes a first bending arm and a second bending arm; when the operating mechanism is in the closed state, the rotation center of the mechanism assembly is close to the connection between the first bending arm and the second bending arm; the impact portion is connected to one end of the first bending arm, and the trigger portion is located at one end of the second bending arm; the end of the trigger portion close to the leakage release is a trigger surface for driving the leakage release; the trigger portion has a reset surface adjacent to the trigger surface, which is used to return the transmission rod to the reset position under the action of the reset portion.

6. A small leakage circuit breaker according to claim 5, characterized in that: Also includes one of the following structures, Structure 1: The trigger part protrudes from the first surface of the second curved arm, and the reset part is provided with a first avoidance groove; when the transmission rod rotates to the reset position, the motion trajectory of the trigger part and the motion trajectory of the reset part intersect, so the trigger part can return to the reset position under the action of the reset part; after the transmission rod is in the reset position, the trigger part avoids interference with the reset part through the first avoidance groove, so as to ensure that the operating mechanism can successfully complete the closing operation; In structure 2, the trigger portion protrudes from the first surface of the second curved arm, so that the transmission rod forms a first avoidance space on one side of the trigger portion, and the first avoidance space is used to avoid partial movement of the reset portion.

7. A small leakage circuit breaker according to claim 1, characterized in that: The handle includes a first handle and a second handle. The first handle and the second handle are independently formed, but are rotatably arranged around the same axis, and a transmission connection is formed between the two. The first handle partially extends out of the shell for user operation, the connecting rod is connected between the first handle and the mechanism assembly, and the reset part is arranged on the second handle.

8. A small leakage circuit breaker according to claim 1, characterized in that: It also includes a moving contact and a stationary contact, wherein the moving contact is rotatably arranged on the mechanism assembly and moves with the mechanism assembly; the mechanism assembly is provided with an unlocking boss, which is located on a side of the moving contact away from the stationary contact, and under the action of the electric repulsive force, the moving contact rotates and hits the unlocking boss to accelerate the unlocking of the mechanism assembly; Or, the handle includes a main body and a handle portion, a first locking hole is provided on the connection part of the handle portion used to connect with the main body, and a second locking hole is provided on the shell. When the operating mechanism is in the closing or opening position, the first locking hole is connected to the second locking hole for the user to padlock.

9. A small leakage circuit breaker according to claim 1, characterized in that: An arc guide plate, a bimetallic strip, a first terminal and a first terminal board are also provided in the shell; the arc guide plate, the bimetallic strip, the first terminal and the first terminal board are all arranged inside the shell; the bimetallic strip comprises a first flat portion, a bent portion and a second flat portion, the first flat portion and the second flat portion are staggered in the length direction, and the two are connected by the bent portion; the first flat portion and the arc guide plate are fixed by riveting or welding, and the second flat portion is used to cooperate with the mechanism component to realize overload protection; the angle between the first flat portion and the second flat portion is an angle A, 150°≤A≤180°; in the height direction, the bimetallic strip is arranged higher than the first terminal board.

10. A small leakage circuit breaker according to claim 1, characterized in that: The mechanism component is one of the following structures: Structure 1, the mechanism assembly includes a contact support, a main spring, a lock and a lock reset spring; the contact support is rotatably connected to the shell, and the main spring is used to connect between the contact support and the shell; the lock is rotatably set on the contact support, and the lock and the contact support jointly form a matching groove; the first end of the connecting rod is connected to the handle, and the second end of the connecting rod extends into the matching groove; the matching groove includes a locking section and an unlocking section; in the process of driving the handle to make the operating mechanism change from opening to closing, due to the relative movement of the contact support and the lock, the size of the locking section is smaller than the diameter of the second end, so that the second end abuts against the locking section, so that the operating mechanism finally remains in the closed state; unlocking of the mechanism assembly means that the lock is triggered, resulting in the size of the locking section being larger than the diameter of the second end of the connecting rod, and the second end of the connecting rod slides into the unlocking section. In this process, the operating mechanism changes from closing to tripping under the action of the main spring; the lock reset spring provides the lock with a biasing force to reset the lock; Structure 2, the mechanism assembly includes a contact support, a main spring, a buckle, a lock and a lock reset spring; the contact support is rotatably connected to the housing, and the main spring is used to connect between the contact support and the housing; The buckle and the lock are both rotatably arranged on the contact support; the connecting rod is connected between the handle and the buckle, the buckle is provided with a first bite portion, and the lock is provided with a second bite portion; in the process of driving the handle to change the operating mechanism from opening to closing, the first bite portion and the second bite portion form a lock, so that the operating mechanism finally remains in the closed state; unlocking of the mechanism assembly means that the lock between the lock buckle and the buckle is released, and the operating mechanism is changed from closing to tripping under the action of the main spring; the lock buckle reset spring provides the lock buckle with a biasing force to reset the lock buckle.

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