Miniature circuit breaker

Abstract

The utility model discloses a miniature circuit breaker, which comprises a circuit breaker shell, an arc running channel, a bimetallic strip, a first wiring terminal and a first terminal board, the arc running channel, the bimetallic strip, the first wiring terminal and the first terminal plate are all arranged in the circuit breaker shell; wherein the arc running channel comprises an inclined section, an assembly section and a bimetal mounting section, and the bimetal mounting section is connected with the inclined section through the assembly section; the bimetal mounting section is used for fixing a bimetal sheet, and the assembling section is used for being clamped with a circuit breaker shell; in the height direction of the miniature circuit breaker, the bimetal mounting section is higher than the inclined section and is not lower than the first terminal plate; the circuit breaker shell forms a reserved space below the bimetal mounting section, and the reserved space is located between the first terminal plate and the inclined section in the length direction of the miniature circuit breaker; the method has the characteristic that the internal layout is more reasonable.

Description

Technical Field

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

[0002] Miniature circuit breakers often require bimetallic strips to achieve overload protection. The structure of existing miniature circuit breakers, such as the DC dual-channel arc extinguishing structure disclosed in CN119092380A, has a bimetallic strip welded to the arc track and the connecting piece (the connecting piece extending from the first terminal plate of the first wiring on the right side). The height of the welding point of the bimetallic strip is the lowest point of the arc track, which is also lower than the first terminal plate of the first wiring on the right side.

[0003] As circuit breakers continue to evolve, if additional functions are to be added, the only solution is to add modules to the outside of the circuit breaker to accommodate circuit boards or sampling components. This is because the internal space of such small circuit breakers is already insufficient to accommodate these components, especially since the space near the bimetallic strip is essentially wasted.

[0004] Therefore, it is necessary to find a more reasonable way to arrange the internal space of the circuit breaker. Summary of the Invention

[0005] In view of this, the purpose of this application is to overcome the shortcomings of the prior art and to provide a miniature circuit breaker.

[0006] This application provides: a miniature circuit breaker, including a circuit breaker housing, a running track, a bimetallic strip, a first terminal block, and a first terminal block; the running track, bimetallic strip, first terminal block, and first terminal block are all disposed inside the circuit breaker housing; wherein, the running track includes an inclined section, an assembly section, and a bimetallic mounting section, the bimetallic mounting section being connected to the inclined section via the assembly section; the bimetallic mounting section is used to fix the bimetallic strip, and the assembly section is used to engage with the circuit breaker housing; in the height direction of the miniature circuit breaker, the bimetallic mounting section is higher than the inclined section and not lower than the first terminal block; a reserved space is formed below the bimetallic mounting section in the circuit breaker housing, and in the length direction of the miniature circuit breaker, the reserved space is located between the first terminal block and the inclined section.

[0007] In some embodiments of this application, the bimetallic strip includes a first flat plate portion, a bent portion, and a second flat plate portion. The first flat plate portion and the second flat plate portion are offset in the length direction of the miniature circuit breaker and are connected by the bent portion. The first flat plate portion is fixed to the bimetallic mounting section by riveting or welding, and the second flat plate portion is used to cooperate with the operating mechanism of the circuit breaker. The angle between the first flat plate portion and the second flat plate portion is an included angle A, where 150°≤A≤180°.

[0008] In some embodiments of this application, a connecting conductor is also included, which is a flexible wire or a conductive sheet; the connecting conductor is connected between the first terminal plate and the bimetallic mounting section, or the connecting conductor is connected between the first terminal plate and the bimetallic sheet.

[0009] In some embodiments of this application, a bimetallic adjustment mechanism is also included. The bimetallic adjustment mechanism is used to change the angle of the bimetallic mounting section to adjust the position of the bimetallic strip. The bimetallic mounting section includes a mounting part and an adjustment part, which are arranged sequentially in the width direction of the miniature circuit breaker. The mounting part is used to fix the bimetallic strip, and the adjustment part is used to cooperate with the bimetallic adjustment mechanism.

[0010] In some embodiments of this application, the first terminal includes a terminal frame and a fastening screw, and the first terminal plate is at least partially inserted through the terminal frame; a wire hole and an adjustment hole are provided on one side surface of the circuit breaker housing, the wire hole is connected to the hollow part of the terminal frame; the adjustment hole is located higher than the wire hole, and the adjustment hole is aligned with the double metal adjustment mechanism so that a tool can be inserted to cooperate with the double metal adjustment mechanism.

[0011] In some embodiments of this application, the junction between the assembly section and the double-metal mounting section is a bent structure. The angle of the double-metal mounting section can be changed by changing the deformation of the bent structure. A first through hole or a first through groove is provided on the bent structure.

[0012] In some embodiments of this application, the dual-metal adjustment mechanism includes an insert nut and an adjustment screw. The insert nut is embedded in the circuit breaker housing, and the adjustment screw penetrates the insert nut. One end of the adjustment screw has a tool opening, and the other end is an abutment. The adjustment part has a second through hole or a second through groove, and the abutment abuts against the opening of the second through hole or the opening of the second through groove, and partially extends into the second through hole or the second through groove.

[0013] In some embodiments of this application, a moving contact is also included, which is welded to the bimetallic strip via a flexible connection. In the height direction of the miniature circuit breaker, the welding point between the moving contact and the bimetallic strip is higher than the first terminal block.

[0014] In some embodiments of this application, one of the assembly section and the circuit breaker housing is provided with a slot, and the other is provided with a protrusion, which is inserted into the slot to form a snap-fit ​​engagement.

[0015] In some embodiments of this application, the number of miniature circuit breakers is at least two, and the reserved spaces in the housings of all circuit breakers are interconnected, with zero-sequence current transformers placed in the interconnected reserved spaces.

[0016] The advantages of this application compared to the prior art are:

[0017] By using such a miniature circuit breaker, the installation position of the bimetallic strip is changed by altering the shape of the running arc, creating a reserved space below the bimetallic strip installation section. This reserved space can be used to place some circuit boards or sampling components, resulting in a circuit breaker with higher space utilization and a more rational internal layout. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of a miniature circuit breaker according to an embodiment of this application is shown;

[0020] Figure 2 A schematic diagram of the interior of a miniature circuit breaker according to an embodiment of this application is shown;

[0021] Figure 3 A schematic diagram of the arc-extinguishing chamber and the arc-running track according to an embodiment of this application is shown;

[0022] Figure 4 A schematic diagram of the running track according to an embodiment of this application is shown;

[0023] Figure 5 A schematic diagram of the zero-sequence current transformer installation according to an embodiment of this application is shown;

[0024] Figure 6 A schematic diagram of a portion of the circuit breaker housing according to an embodiment of this application is shown;

[0025] Figure 7 A schematic diagram of a bimetallic sheet according to an embodiment of this application is shown;

[0026] Figure 8 This diagram shows a partially enlarged schematic view of the running track according to an embodiment of this application;

[0027] Figure 9 A schematic diagram of the dual-metal adjustment mechanism according to an embodiment of this application is shown;

[0028] Figure 10 A schematic diagram of the adjustment hole and the threading hole in an embodiment of this application is shown. Detailed Implementation

[0029] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein 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 and are only used to explain this application, and should not be construed as limiting this application.

[0030] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0032] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0033] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature. Example

[0034] like Figures 1-10As shown, an embodiment of this application is a miniature circuit breaker, which includes a circuit breaker housing 100, a running track 200, a bimetallic strip 300, a first terminal block 400, and a first terminal block 500.

[0035] The circuit breaker housing 100 includes left and right half-shells 101 and 102, which are fastened by rivets after being spliced ​​and fixed.

[0036] The arc runner 200 serves as the arc initiation element for the moving contact 600. One end of the arc runner 200 extends below the arc extinguishing chamber 700, which facilitates the transfer of the electric arc through the arc runner 200 to the area below the arc extinguishing chamber 700.

[0037] Here, the running track 200 specifically includes a horizontal section 201, an inclined section 202, an assembly section 203, and a double-metal installation section 204. Here, the horizontal section 201 is located below the arc-extinguishing chamber 700, and one end of the horizontal section 201 is connected to the inclined section 202.

[0038] The inclined section 202 connects the horizontal section 201 and the assembly section 203. It is a gradually rising section, hence the name inclined section 202. Specifically, it rises gradually from the horizontal section 201 to the assembly section 203.

[0039] The assembly section 203 is fixed to the circuit breaker housing 100 by a snap-fit ​​connection. Here, one of the assembly section 203 and the circuit breaker housing 100 has a slot 203a, and the other has a protrusion 100a. The protrusion 100a inserts into the slot 203a to form a snap-fit ​​engagement. Preferably, the slot 203a is located on the assembly section 203, while the protrusion 100a is located on the circuit breaker housing 100. This snap-fit ​​fixation ensures greater stability after the arc track 200 is installed on the housing.

[0040] Bimetallic mounting section 204, as the name suggests, is used to mount the bimetallic strip 300. Here, bimetallic mounting section 204 is located on one side of assembly section 203 and connected to assembly section 203. Here, "one side" refers to one side along the length L of the miniature circuit breaker.

[0041] Here, in the height direction H of the miniature circuit breaker, the height of the double metal mounting section 204 is higher than any position of the inclined section 202, and the height of the double metal mounting section 204 is not lower than the first terminal block 500.

[0042] This arrangement creates space below the double-metal mounting section 204; specifically, the circuit breaker housing 100 forms a reserved space S below the double-metal mounting section 204. This reserved space S, along the length L of the miniature circuit breaker, is located between the first terminal block 500 and the inclined section 202. This reserved space S allows for the placement of other components (such as current transformers or PCB boards) within the miniature circuit breaker. Taking a miniature circuit breaker with two or more poles as an example, all reserved spaces S are connected, meaning they are connected along the width of the circuit breaker, and the zero-sequence current transformer 800 is installed within the connected reserved space S.

[0043] In this way, by changing the structure of the running arc 200, the installation position of the bimetallic strip 300 is moved, and the internal space of the circuit breaker is rearranged to reserve space S for accommodating other components, resulting in a more streamlined and compact structure.

[0044] The first terminal block 400 and the first terminal plate 500 are used to connect the main circuit conductor on the moving contact 600 side to the external circuit. Specifically, the first terminal block 400 includes a wiring frame 401 and a wiring screw 402, and the first terminal plate 500 is inserted into the wiring frame 401. A connecting conductor 501 is soldered onto the first terminal plate 500, and the connecting conductor 501 is soldered onto the bimetallic strip 300. Of course, as an alternative, the connecting conductor 501 can be soldered onto the bimetallic mounting section 204 instead of the bimetallic strip 300. Here, the connecting conductor 501 uses a rigid conductive sheet, but its thickness will be thinner than that of the terminal block. As an alternative, the connecting conductor 501 can also be replaced with a flexible wire. In any case, the electrical connection between the terminal block and the bimetallic strip 300 can be completed in this way.

[0045] The moving contact 600 is welded to the bimetallic strip 300 via a flexible connection. This ensures an electrical connection between the moving contact 600 and the first terminal 400. Here, in the height direction H of the miniature circuit breaker, the welding point between the moving contact 600 and the bimetallic strip 300 is higher than the first terminal plate 500. This arrangement allows for a more rational layout of the flexible connection and avoids interference.

[0046] Of course, in addition to the first terminal block 400 and the first terminal board 500, there are also a second terminal block and a second terminal board, which are used to make electrical connections with the stationary contact. Thus, when the two terminals are connected to an external circuit, the moving and stationary contacts make contact, and the circuit is connected. Since the connection methods of the second terminal block, the second terminal board, the stationary contact, and other components are common knowledge in this field, they will not be described in detail here.

[0047] For the bimetallic strip 300, due to its upward mounting position, to ensure that the total length of the bimetallic strip 300 remains unchanged (overload tripping performance is related to its total length), the bimetallic strip 300 does not adopt a traditional flat structure, but rather a twisted structure. Specifically, the bimetallic strip 300 includes a first flat section 301, a bent section 302, and a second flat section 303. The first flat section 301 and the second flat section 303 are offset in the length direction L of the miniature circuit breaker and are connected by the bent section 302. Here, the first flat section 301 is fixed to the bimetallic mounting section 204 by welding, although this can also be replaced by riveting. The second flat section 303 is used to cooperate with the circuit breaker's operating mechanism, specifically with the bimetallic pull rod 901 on the latch 900. When an overload occurs, the bimetallic strip 300 bends, pulling the latch 900 to rotate via the bimetallic pull rod 901, causing the operating mechanism to trip.

[0048] Since both the first plate portion 301 and the second plate portion 303 are plate-shaped, there will be an included angle A between them. Here, the included angle A is 180°. Of course, the included angle A can also be other angles, as long as 150°≤A≤180° is satisfied.

[0049] This structure connects the two flat sections through the bending section 302, so that the bimetallic strip 300 can have the same length as the bimetallic strip 300 in the prior art. While ensuring that the installation position of the bimetallic strip 300 is moved upward compared to the prior art, it retains the original overload tripping performance (the overload tripping performance is related to the total length of the bimetallic strip 300).

[0050] To enable adjustable overload performance of the bimetallic strip 300, a bimetallic adjustment mechanism 1000 is also included.

[0051] Here, the bimetallic mounting section 204 includes a mounting part 204a and an adjusting part 204b, which are arranged sequentially in the width direction D of the miniature circuit breaker. The mounting part 204a is used to weld the bimetallic strip 300, while the adjusting part 204b cooperates with the bimetallic adjusting mechanism 1000. The bimetallic adjusting mechanism 1000 allows the bimetallic mounting section 204 to bend (i.e., change the angle of the bimetallic mounting section 204), thereby changing the angle of the bimetallic strip 300 and achieving adjustable overload performance.

[0052] Since the bimetallic adjustment mechanism 1000 is also located inside the circuit breaker housing 100, there is an adjustment hole 100b on the circuit breaker housing 100. Here, a wire-passing hole 100c and an adjustment hole 100b are provided on one side surface of the circuit breaker housing 100. The wire-passing hole 100c corresponds to the terminal frame 401, specifically communicating with the hollow portion of the terminal frame 401, allowing external wires to be passed through the terminal frame 401 to complete the wiring. The adjustment hole 100b is located above the wire-passing hole 100c and is used to align with the bimetallic adjustment mechanism 1000, allowing tools to be inserted into the adjustment hole 100b to drive the bimetallic adjustment mechanism 1000.

[0053] The arrangement of the adjustment hole 100b and the wire hole 100c is different from the prior art and is more suitable for the double metal adjustment of the double metal mounting position in this application, while effectively avoiding terminal blocks and other related components.

[0054] Here, the junction between the assembly section 203 and the double-metal mounting section 204 is a bending structure 205. When the double-metal adjustment mechanism 1000 acts on the double-metal mounting section 204, the main deformation part is this bending structure 205. The angle of the double-metal mounting section 204 is changed through the deformation of this bending structure 205. Here, the bending structure 205 has a first through hole 205a. The design of the first through hole 205a reduces the physical dimensions of the bending structure 205, making it easier for the bending structure 205 to bend and deform, resulting in a more obvious and easier adjustment effect. Of course, as an alternative, the first through hole 205a can also be replaced with a first through groove, achieving the same effect.

[0055] The bimetallic adjustment mechanism 1000 includes an insert nut 1010 and an adjusting screw 1020. The insert nut 1010 is embedded within the circuit breaker housing 100. The adjusting screw 1020 passes through the insert nut 1010, and its two ends have a tool port 1020a and an abutment 1020b, respectively. The tool port 1020a faces the adjustment hole 100b, while the abutment 1020b faces the adjustment section 204b.

[0056] Here, the adjusting part 204b has a second through groove 204c, and the abutment 1020b abuts against the opening of the second through groove 204c. This ensures that the abutment 1020b and the adjusting part 204b are in full contact, guaranteeing stable interaction between them and facilitating the adjustment of the bimetallic alloy. Of course, as an alternative, the second through groove 204c can also be replaced with a second through hole, achieving the same effect.

[0057] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0058] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A miniature circuit breaker, comprising a circuit breaker housing, a running arc track, a bimetallic strip, a first terminal block, and a first terminal block; wherein the running arc track, the bimetallic strip, the first terminal block, and the first terminal block are all disposed inside the circuit breaker housing; characterized in that: The running track includes an inclined section, an assembly section, and a bimetallic mounting section. The bimetallic mounting section is connected to the inclined section through the assembly section. The bimetallic mounting section is used to fix the bimetallic strip, and the assembly section is used to snap onto the circuit breaker housing. In the height direction of the miniature circuit breaker, the bimetallic mounting section is higher than the inclined section and not lower than the first terminal plate. The circuit breaker housing forms a reserved space below the bimetallic mounting section. In the length direction of the miniature circuit breaker, the reserved space is located between the first terminal plate and the inclined section.

2. The miniature circuit breaker according to claim 1, characterized in that: The bimetallic strip includes a first flat plate portion, a bent portion, and a second flat plate portion. The first flat plate portion and the second flat plate portion are offset along the length of the miniature circuit breaker and are connected by the bent portion. The first flat plate portion is fixed to the bimetallic mounting section by riveting or welding, and the second flat plate portion is used to cooperate with the operating mechanism of the circuit breaker. The angle between the first flat plate portion and the second flat plate portion is an included angle A, where 150°≤A≤180°.

3. A miniature circuit breaker according to claim 1, characterized in that: It also includes a connecting conductor, which is a flexible wire or a conductive sheet; the connecting conductor is connected between the first terminal block and the bimetallic mounting section, or the connecting conductor is connected between the first terminal block and the bimetallic sheet.

4. A miniature circuit breaker according to claim 1, characterized in that: It also includes a bimetallic adjustment mechanism, which is used to change the angle of the bimetallic mounting section to adjust the position of the bimetallic strip; the bimetallic mounting section includes a mounting part and an adjustment part, which are arranged sequentially in the width direction of the miniature circuit breaker; the mounting part is used to fix the bimetallic strip, and the adjustment part is used to cooperate with the bimetallic adjustment mechanism.

5. A miniature circuit breaker according to claim 4, characterized in that: The first terminal block includes a terminal frame and fastening screws. The first terminal plate is at least partially inserted through the terminal frame. A wire hole and an adjustment hole are provided on one side surface of the circuit breaker housing. The wire hole is connected to the hollow part of the terminal frame. The adjustment hole is located higher than the wire hole and is aligned with the double metal adjustment mechanism so that a tool can be inserted to cooperate with the double metal adjustment mechanism.

6. A miniature circuit breaker according to claim 4, characterized in that: The junction between the assembly section and the double-metal mounting section is a bent structure. By changing the deformation of this bent structure, the angle of the double-metal mounting section can be changed. A first through hole or a first through groove is provided on the bent structure.

7. A miniature circuit breaker according to claim 4, characterized in that: The dual-metal adjustment mechanism includes an insert nut and an adjustment screw. The insert nut is embedded in the circuit breaker housing, and the adjustment screw penetrates the insert nut. One end of the adjustment screw has a tool opening, and the other end is an abutment. The adjustment part has a second through hole or a second through groove. The abutment abuts against the opening of the second through hole or the opening of the second through groove, and partially extends into the second through hole or the second through groove.

8. A miniature circuit breaker according to claim 1, characterized in that: It also includes a moving contact, which is welded to the bimetallic strip via a flexible connection. In the height direction of the miniature circuit breaker, the welding point between the moving contact and the bimetallic strip is higher than the first terminal block.

9. A miniature circuit breaker according to claim 1, characterized in that: One of the assembly section and the circuit breaker housing is provided with a slot, and the other is provided with a protrusion. The protrusion is inserted into the slot to form a snap-fit.

10. A miniature circuit breaker according to any one of claims 1-9, characterized in that: The number of miniature circuit breakers is at least two, and the reserved spaces in the housings of all circuit breakers are interconnected, with zero-sequence current transformers placed in the interconnected reserved spaces.

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