An improved bimetallic strip for fast-response circuit breakers

Abstract

This utility model discloses an improved bimetallic strip for a fast-response circuit breaker, including a positive electrode connecting plate. One end of the positive electrode connecting plate is fixedly connected to a copper alloy plate and an iron-nickel alloy plate, and an expansion component for accelerating bending is provided between the copper alloy plate and the iron-nickel alloy plate. When the circuit is overloaded, the current increases sharply, and the heat generated is conducted to the copper alloy plate and the iron-nickel alloy plate through the positive electrode connecting plate. Due to the excellent thermal conductivity of the copper alloy material, the expansion plate quickly absorbs the heat and begins to expand significantly due to its high coefficient of thermal expansion. At the same time, the transverse limiting plate and the extrusion plate made of iron-nickel alloy material also expand to a certain extent due to heat, causing the size of the extrusion groove to shrink synchronously. The reduction in the size of the extrusion groove provides a more compact space for the expansion plate to expand, further enhancing the expansion effect of the expansion plate in a limited space. As the expansion plate continues to expand and fill the extrusion groove.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, specifically to an improved bimetallic strip for a fast-response circuit breaker. Background Technology

[0002] Traditional bimetallic strips have a slow response speed. When an overload occurs in the circuit, they rely solely on the natural difference in the thermal expansion coefficients of the two metals to cause bending deformation, which is insufficient to quickly trigger the circuit breaker. This results in a prolonged overload current, increasing the risk of electrical equipment damage, fires, and other accidents. Therefore, those skilled in the art have provided an improved bimetallic strip for fast-response circuit breakers to address the problems mentioned in the background section. Utility Model Content

[0003] The purpose of this invention is to provide an improved bimetallic strip for fast-response circuit breakers to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution:

[0005] An improved bimetallic strip for a fast-response circuit breaker includes a positive electrode connecting plate, one end of which is fixedly connected to a copper alloy plate and an iron-nickel alloy plate, and an expansion component for accelerating bending is provided between the copper alloy plate and the iron-nickel alloy plate.

[0006] Furthermore, the expansion assembly includes a lateral limiting plate, an extrusion plate, an expansion plate, and an extrusion groove, with a set of uniformly distributed expansion plates fixedly connected to the lower surface of the copper alloy plate.

[0007] Furthermore, a set of uniformly distributed extrusion plates are fixedly connected to the upper surface of the iron-nickel alloy plate, and an extrusion groove is formed between two adjacent extrusion plates and the iron-nickel alloy plate.

[0008] Furthermore, two pairs of transverse limiting plates are fixedly connected between the two adjacent extrusion plates. The transverse limiting plates can seal the extrusion groove, making it form an extrusion groove with the opening facing upward, and the number of extrusion grooves corresponds to the number of expansion plates.

[0009] Furthermore, a force-applying plate is fixedly connected to the end of the copper alloy plate and the iron-nickel alloy plate away from the positive electrode connecting plate, and a negative electrode solder point is fixedly connected to the upper surface of the force-applying plate.

[0010] Furthermore, the expansion plate is made of copper alloy, and the transverse limiting plate and the extrusion plate are made of iron-nickel alloy.

[0011] By adopting the above technical solution

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. The expansion plate is made of copper alloy, which, due to its excellent thermal conductivity and coefficient of thermal expansion, can quickly absorb heat and expand significantly when the circuit is overloaded. The lateral limiting plate and the extrusion plate are made of iron-nickel alloy. Although their coefficient of thermal expansion is lower, they still expand to a certain extent when heated. This expansion causes the extrusion groove to shrink synchronously. The reduction in the size of the extrusion groove provides a more compact space for the expansion plate to expand, making the expansion effect of the expansion plate more significant within a limited space. The combination of these two materials generates a strong extrusion force through the difference in thermal expansion of the materials, accelerating the bending deformation of the bimetallic strip, significantly shortening the circuit breaker response time, and interrupting overload current faster than traditional designs, effectively reducing the probability of electrical accidents.

[0014] 2. The high thermal conductivity of copper alloy allows the expansion plate to quickly transfer heat to the entire bimetallic strip structure, promoting uniform heating and preventing performance degradation due to localized overheating. Meanwhile, the iron-nickel alloy lateral limiting plate and extrusion plate, while expanding and contracting the extrusion grooves and restricting the direction of the expansion plate, also provide a stable mechanical framework for the bimetallic strip as a whole, making force transmission more uniform and efficient during bending deformation. Working together, these two components optimize the thermal conductivity and mechanical properties of the bimetallic strip, improving the accuracy and stability of the circuit breaker during overload protection and providing reliable protection for the safe operation of electrical systems. Attached Figure Description

[0015] Figure 1 A schematic diagram of the overall structure of a bimetallic strip for an improved fast-response circuit breaker;

[0016] Figure 2 This is a schematic diagram of the exploded structure of a bimetallic strip for an improved fast-response circuit breaker.

[0017] Figure 3 This is a side cross-sectional view of a bimetallic strip used in an improved fast-response circuit breaker.

[0018] In the diagram: 1. Force plate; 2. Negative electrode solder joint; 3. Copper alloy plate; 4. Positive electrode connecting plate; 5. Lateral limiting plate; 6. Extrusion plate; 7. Iron-nickel alloy plate; 8. Expansion plate; 9. Extrusion groove. Detailed Implementation

[0019] To make the technical means, creative features, achieved objectives and effects of this utility model easier to understand, the present utility model is further described below in conjunction with specific embodiments. In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0020] Please see Figures 1-3 This utility model provides an embodiment of an improved bimetallic strip for a fast-response circuit breaker, including a positive electrode connecting plate 4. One end of the positive electrode connecting plate 4 is fixedly connected to a copper alloy plate 3 and an iron-nickel alloy plate 7, and an expansion component for accelerating bending is provided between the copper alloy plate 3 and the iron-nickel alloy plate 7.

[0021] In this embodiment, the expansion assembly includes a transverse limiting plate 5, an extrusion plate 6, an expansion plate 8, and an extrusion groove 9. A set of uniformly distributed expansion plates 8 are fixedly connected to the lower surface of the copper alloy plate 3, and a set of uniformly distributed extrusion plates 6 are fixedly connected to the upper surface of the iron-nickel alloy plate 7. An extrusion groove 9 is formed between two adjacent extrusion plates 6 and the iron-nickel alloy plate 7. Two pairs of transverse limiting plates 5 are fixedly connected between two adjacent extrusion plates 6. The transverse limiting plates 5 can seal the extrusion groove 9, forming an upward-opening extrusion groove 9. The number of extrusion grooves 9 corresponds to the number of expansion plates 8. The copper alloy plate 3 is prepared using a high-precision casting or rolling process. Utilizing its excellent thermal conductivity and coefficient of thermal expansion, a set of uniformly distributed expansion plates 8 are fixedly connected to the lower surface of the copper alloy plate 3 using precision machining techniques (such as etching, stamping, or welding). Plate 8 is also made of copper alloy material, and the size, shape and distribution density of expansion plate 8 are customized according to the protection requirements of the circuit breaker to ensure that appropriate expansion force can be generated under overload. Iron-nickel alloy plate 7 is prepared by rolling or forging process. On the upper surface of iron-nickel alloy plate 7, a set of uniformly distributed extrusion plates 6 are fixedly connected by welding or integral molding. Extrusion grooves 9 are formed between adjacent extrusion plates 6 and iron-nickel alloy plate 7. At the same time, two pairs of transverse limiting plates 5 are fixed between two adjacent extrusion plates 6 by welding or embedded connection. A gap is left between the transverse limiting plates 5 to achieve separation. The transverse limiting plates 5 seal the extrusion grooves 9 into an upward-opening structure. Both transverse limiting plates 5 and extrusion plates 6 are made of iron-nickel alloy material, and their size and position accuracy must be strictly controlled to ensure precise matching with expansion plate 8.

[0022] In this embodiment, a force-applying plate 1 is fixedly connected to the end of the copper alloy plate 3 and the iron-nickel alloy plate 7 away from the positive electrode connection plate 4. A negative electrode solder joint 2 is fixedly connected to the upper surface of the force-applying plate 1. The expansion plate 8 is made of copper alloy material, and the transverse limiting plate 5 and the extrusion plate 6 are made of iron-nickel alloy material. The force-applying plate 1 is fixedly connected to the end of the copper alloy plate 3 and the iron-nickel alloy plate 7 away from the positive electrode connection plate 4 by welding or riveting. The force-applying plate 1 provides a force point for the bending deformation of the bimetallic strip. The negative electrode solder joint 2 is fixedly connected to the upper surface of the force-applying plate 1 by welding or electroplating process for connection with the negative electrode of the circuit.

[0023] When the circuit experiences an overload, the current increases sharply. The generated heat is conducted through the positive electrode connecting plate 4 to the copper alloy plate 3 and the iron-nickel alloy plate 7. Due to the excellent thermal conductivity of the copper alloy material, the expansion plate 8 quickly absorbs the heat and begins to expand significantly due to its high coefficient of thermal expansion. At the same time, the transverse limiting plate 5 and the extrusion plate 6, made of iron-nickel alloy material, also expand to a certain extent due to heat, causing the size of the extrusion groove 9 to shrink synchronously. The reduction in the size of the extrusion groove 9 provides a more compact space for the expansion plate 8 to expand, further enhancing the expansion effect of the expansion plate 8 within the limited space. As the expansion plate 8 expands and fills the extrusion groove 9, a strong extrusion force is generated between the expansion plate 8 and the extrusion groove 9. This extrusion force pushes the copper alloy plate 3 and the iron-nickel alloy plate 7 to bend and deform. Due to the difference in the thermal expansion coefficients of the copper alloy plate 3 and the iron-nickel alloy plate 7 and the synergistic effect of the expansion components, the bending speed and degree of the bimetallic strip are greatly improved compared with the traditional bimetallic strip. The bending deformation of the bimetallic strip is transmitted to the triggering mechanism of the circuit breaker through the force plate 1. When the bending degree reaches the preset threshold, the triggering mechanism is activated to quickly cut off the circuit and realize the overload protection of the circuit.

[0024] The expansion plate 8 is made of copper alloy, which, due to its excellent thermal conductivity and coefficient of thermal expansion, can quickly absorb heat and expand significantly when the circuit is overloaded. The transverse limiting plate 5 and the extrusion plate 6 are made of iron-nickel alloy. Although their coefficient of thermal expansion is relatively low, they still expand to a certain extent when heated. This expansion causes the extrusion groove 9 to shrink synchronously. The reduction in the size of the extrusion groove 9 provides a more compact space for the expansion plate 8 to expand, making the expansion effect of the expansion plate 8 more significant within a limited space. The two work together to generate strong extrusion force through the difference in thermal expansion of the materials, accelerating the bending deformation of the bimetallic strip, significantly shortening the circuit breaker response time, and interrupting overload current faster than traditional designs, effectively reducing the probability of electrical accidents. The high thermal conductivity of copper alloy allows the expansion plate 8 to quickly transfer heat to the entire bimetallic strip structure, promoting uniform heating of the bimetallic strip and avoiding performance degradation caused by local overheating. The iron-nickel alloy transverse limiting plate 5 and extrusion plate 6, while expanding and contracting the extrusion groove 9 due to heat and restricting the direction of the expansion plate 8, also provide a stable mechanical framework for the bimetallic strip as a whole, making the force transmission of the bimetallic strip more uniform and efficient during bending deformation. Working together, they optimize the thermal conductivity and mechanical properties of the bimetallic strip, improve the accuracy and stability of the circuit breaker during overload protection, and provide reliable protection for the safe operation of the electrical system.

[0025] This specification describes the embodiments, but not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An improved bimetallic strip for a fast-response circuit breaker, comprising a positive electrode connection plate (4), characterized in that: One end of the positive electrode connecting plate (4) is fixedly connected to a copper alloy plate (3) and an iron-nickel alloy plate (7), and an expansion component is provided between the copper alloy plate (3) and the iron-nickel alloy plate (7); the expansion component includes a transverse limiting plate (5), an extrusion plate (6), an expansion plate (8) and an extrusion groove (9), and a set of uniformly distributed expansion plates (8) are fixedly connected to the lower surface of the copper alloy plate (3).

2. The improved bimetallic strip for a fast-response circuit breaker according to claim 1, characterized in that, A set of uniformly distributed extrusion plates (6) are fixedly connected to the upper surface of the iron-nickel alloy plate (7), and an extrusion groove (9) is formed between two adjacent extrusion plates (6) and the iron-nickel alloy plate (7).

3. The improved bimetallic strip for a fast-response circuit breaker according to claim 2, characterized in that, Two pairs of transverse limiting plates (5) are fixedly connected between the two adjacent extrusion plates (6). The transverse limiting plates (5) can seal the extrusion groove (9) so that it forms an extrusion groove (9) with the opening facing upward. The number of extrusion grooves (9) corresponds to the number of expansion plates (8).

4. The improved bimetallic strip for a fast-response circuit breaker according to claim 3, characterized in that, The copper alloy plate (3) and the iron-nickel alloy plate (7) are fixedly connected to a force-applying plate (1) at the end away from the positive electrode connecting plate (4), and a negative electrode solder point (2) is fixedly connected to the upper surface of the force-applying plate (1).

5. The improved bimetallic strip for a fast-response circuit breaker according to claim 4, characterized in that, The expansion plate (8) is made of copper alloy, and the transverse limiting plate (5) and the extrusion plate (6) are made of iron-nickel alloy.

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