Miniature circuit breaker

Abstract

The utility model discloses a miniature circuit breaker, which comprises a shell provided with an arc extinguish chamber. The arc extinguish chamber is connected with an upper arc striking sheet; the upper arc striking sheet comprises an upper arc striking sheet conductive section and an upper arc striking sheet arc striking section; the conductive section of the upper arc striking sheet is made of copper, and the arc striking section of the upper arc striking sheet is made of iron; the upper arc striking sheet conductive section and the upper arc striking sheet arc striking section are connected through a solder layer; a moving contact plate used for being matched with the upper arc striking sheet is arranged in front of the upper arc striking sheet, and an electric shock part used for being in contact with the upper arc striking sheet is arranged on the moving contact plate. The moving contact plate is made of copper-iron-phosphorus alloy.

Description

Technical Field

[0001] The utility model belongs to the technical field of electric power, and in particular relates to a small circuit breaker. Background Art

[0002] Existing miniature circuit breakers include a housing in which a moving contact, an arc extinguishing chamber, and an upper arc-striking plate and a lower arc-striking plate are provided for directing the tripping arc to the arc extinguishing chamber. The upper arc-striking plate includes a conductive segment provided with a static contact and an arc-striking segment extending backward into the arc extinguishing chamber. The moving contact can move backward to close the circuit with the static contact. When opening the circuit, the moving contact moves forward and is stopped by the upper end of the upper arc-striking plate. The miniature circuit breaker also includes a guard plate, a terminal, and a bimetallic plate for overheating protection. The guard plate is connected to the lower arc-striking plate, the bimetallic plate, and the terminal. In actual use, the moving contact moves backward to close the circuit with the static contact. When opening the circuit, the moving contact moves forward until it is stopped by the upper end of the lower arc-striking plate. The arc generated by the opening of the moving contact can be directed to the arc extinguishing chamber by the upper and lower arc-striking plates. The current upper arc-starting plate has a conductive section made of copper and an arc-starting section made of iron. These sections are fixed together by spot welding, which results in high contact resistance and a high temperature rise. The existing moving contact consists of a moving contact plate and a silver dot. The moving contact plate is made of copper, and during processing, the silver dot needs to be welded to the moving contact plate. Consequently, existing circuit breakers suffer from high temperature rises and complex manufacturing. Utility Model Content

[0003] Therefore, the present invention provides a small circuit breaker to solve the problems of high temperature rise and complex processing of existing circuit breakers.

[0004] To this end, the present invention provides the following technical solutions:

[0005] A miniature circuit breaker comprises a housing, wherein an arc extinguishing chamber is provided on the housing;

[0006] The arc extinguishing chamber is connected to an upper arc striking piece; the upper arc striking piece includes an upper arc striking piece conductive section and an upper arc striking piece arc striking section; the upper arc striking piece conductive section is made of copper, and the upper arc striking piece arc striking section is made of iron; the upper arc striking piece conductive section and the upper arc striking piece arc striking section are connected by a solder layer;

[0007] A moving contact plate for cooperating with the upper arc-striking piece is provided in front of the upper arc-striking piece, and an electric contact part for contacting the upper arc-striking piece is provided on the moving contact plate; the moving contact plate is made of copper-iron-phosphorus alloy.

[0008] Optionally, the contact portion is a protrusion integrally formed on the moving contact plate.

[0009] Optionally, a static contact portion cooperating with the contact portion is provided on the arc-striking segment of the upper arc-striking piece.

[0010] Optionally, the static contact portion is made of the same material as the moving contact plate, and the static contact portion is welded to the arc-striking segment of the upper arc-striking plate.

[0011] Optionally, the conductive segment of the upper arc-starting piece includes a straight portion, an end of the straight portion is bent to one side to form a bent portion, and an end of the bent portion is provided with a connecting portion for connecting to the arc-starting segment of the upper arc-starting piece.

[0012] Optionally, the arc-striking segment of the upper arc-striking piece includes a static contact portion, one end of the static contact portion is provided with a first bending portion for connecting to the conductive segment of the upper arc-striking piece, and the other end of the static contact portion is provided with a second bending portion.

[0013] Optionally, the solder layer is a copper solder layer.

[0014] Optionally, a lower arc-striking piece for cooperating with the moving contact plate is further provided below the moving contact plate in the housing; the lower arc-striking piece is connected to the arc extinguishing chamber.

[0015] Optionally, the moving contact plate is connected to a transmission mechanism, and the transmission mechanism is used to control the closing and opening of the miniature circuit breaker.

[0016] Optionally, the moving contact plate is made of CuFe0.1P alloy.

[0017] The beneficial effects of the utility model are:

[0018] The upper arc-starting plate features a copper conductive segment and an iron arc-starting segment welded together using a solder layer. This results in a low temperature rise and excellent conductivity. The moving contact plate and contacts are made of the same material, simplifying fabrication. This miniature circuit breaker solves the problems of high temperature rise and complex fabrication associated with existing circuit breakers. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 Schematic diagram of circuit breaker structure

[0021] Figure 2 Schematic diagram of the upper arc-starting piece;

[0022] Figure 3 Schematic diagram of the components of the upper arc-starting plate;

[0023] Figure 4 Schematic diagram of the upper arc-starting plate welding structure;

[0024] Figure 5 Schematic diagram of the moving contact plate.

[0025] Markings in the figure: 1. upper arc-striking plate, 11. upper arc-striking plate conductive segment, 12. upper arc-striking plate arc-striking segment, 13. solder layer, 2. moving contact plate, 21 contact portion, 111 straight portion, 112 bent portion, 121 static contact portion, 122 first bent portion, 123 second bent portion, 31 housing, 32 arc-extinguishing chamber, 33. lower arc-striking plate, 34 transmission mechanism. DETAILED DESCRIPTION

[0026] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0028] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0029] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] The miniature circuit breaker of the utility model is as follows Figures 1 to 5 As shown, it includes a housing 31, on which are mounted the moving contact plate 2, an arc extinguishing chamber 32, an upper arc-strike plate 1, a lower arc-strike plate 33, and a transmission mechanism 34. The upper arc-strike plate 1 includes a conductive segment and an arc-strike segment for directing the corresponding arc into the arc extinguishing chamber. The tail end of the arc-strike segment extends to the gas outlet side of the arc extinguishing chamber 32. The lower arc-strike plate 33 is connected to the arc extinguishing chamber from below.

[0031] The upper arc-striking piece includes an upper arc-striking piece conductive segment 11 and an upper arc-striking piece arc-striking segment 12; the upper arc-striking piece conductive segment 11 is made of copper, and the upper arc-striking piece arc-striking segment 12 is made of iron; the upper arc-striking piece conductive segment 11 and the upper arc-striking piece arc-striking segment 12 are connected by a solder layer 13;

[0032] A movable contact plate 2 is provided in front of the upper arc-striking plate 1 for cooperating with the upper arc-striking plate 1. The movable contact plate 2 is provided with a contact portion 21 for contacting the upper arc-striking plate 1. The movable contact plate is made of a copper-iron-phosphorus alloy. The contact portion is integrally formed on the movable contact plate and is shaped like a convex block.

[0033] In actual use, driven by the transmission mechanism 34, the moving contact plate 2 moves backward and closes the circuit with the static contact part 121 of the upper arc-striking piece 1. When opening is required, driven by the transmission mechanism 34, the moving contact plate 2 moves forward until it is stopped by the upper end of the lower arc-striking piece 33. The arc generated by the opening of the moving contact can be led to the arc extinguishing chamber 32 by the upper and lower arc-striking pieces.

[0034] Among them, the upper arc-starting piece 1 in the utility model has a structure as follows Figure 2 、 Figure 3 、 Figure 4 As shown, the upper arc-starting piece conductive segment 11 includes a straight portion 111 , the end of the straight portion 111 is bent to one side to form a bent portion 112 , and the end of the bent portion 112 is provided with a connecting portion for connecting to the upper arc-starting piece arc-starting segment 12 .

[0035] The arc-striking section of the upper arc-striking piece includes a static contact portion 121. One end of the static contact portion 121 is provided with a first bent portion 122 for connecting to the conductive section of the upper arc-striking piece. The other end of the static contact portion is provided with a second bent portion 123. The second bent portion 123 is mainly used to fix the upper arc-striking piece to the circuit breaker housing.

[0036] The copper-iron-phosphorus alloy is a CuFe0.1P alloy. CuFe0.1P alloy is a high-performance copper-based material that combines the excellent electrical and thermal conductivity of copper with the strengthening effects of iron and phosphorus. Its chemical composition is based on copper (Cu), with trace amounts of iron (Fe, 0.05%-0.15%) and phosphorus (P, 0.025%-0.04%) added. Iron enhances strength, while phosphorus stabilizes the alloy structure and enhances oxidation resistance. The CuFe0.1P alloy used in this invention contains 0.1 wt% Fe, 0.03 wt% P, and the balance is Cu. The CuFe0.1P alloy has a density of 8.91 g / cm³ and a melting point of 1083°C. Its electrical conductivity reaches 85% IACS (International Annealed Copper Standard), reaching the level of pure copper. Its thermal conductivity is 350 W / m·K. This alloy balances conductivity, strength and environmental adaptability by optimizing composition and processing, making it an ideal material for high-precision electronic devices and harsh working conditions.

[0037] Different from the prior art in which the upper arc-starting plate conductive segment 11 and the upper arc-starting plate arc-starting segment 12 are welded by resistance welding, the welding method in the present invention is brazing, medium frequency welding or friction welding.

[0038] The welding method in this embodiment specifically adopts brazing. Brazing is a process of connecting workpieces by melting filler metal (brazing material). Its core feature is that the base material does not melt, and only relies on the brazing material to wet, flow and combine with the base material to form a joint. It is suitable for connecting different kinds of materials, and therefore is suitable for the copper-iron connection in the present invention. The joint is flat and smooth, with little deformation, and is suitable for precision devices. It is convenient for mass production, with high efficiency and low energy consumption. In scenarios such as circuit breaker arcing plates, a reliable connection of high-conductivity joints can be achieved by selecting a matching copper-based brazing material (such as the CuP series). Compared with the connection method of resistance welding in the prior art, it can significantly reduce the resistance at the solder joint connection, avoid the problem of high resistance at the solder joint, resulting in temperature rise, reduced structural strength and arcing ability. A solder layer 13 is provided between the conductive section of the upper arcing plate and the arcing section of the upper arcing plate. Specifically, the solder layer is copper. The end of the bending portion 112 and the end of the first bending portion 122 are welded together by solder to form Figure 4 The structure shown.

[0039] Furthermore, in some specific embodiments, a static contact part cooperating with the contact part 21 is provided on the arc-striking section of the upper arc-striking piece; the static contact part is made of the same material as the moving contact plate, and the static contact part is welded on the arc-striking section of the upper arc-striking piece.

[0040] In this utility model, the upper arc-starting plate is constructed with a copper conductive segment and an iron arc-starting segment welded together using a solder layer. This results in a low temperature rise and excellent conductivity. The moving contact plate and contacts are made of the same material, simplifying fabrication. This miniature circuit breaker solves the problems of high temperature rise and complex fabrication associated with existing circuit breakers.

[0041] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A miniature circuit breaker, characterized in that: It comprises a shell, wherein the shell is provided with an arc extinguishing chamber; The arc extinguishing chamber is connected to an upper arc striking piece; the upper arc striking piece includes an upper arc striking piece conductive section and an upper arc striking piece arc striking section; the upper arc striking piece conductive section is made of copper, and the upper arc striking piece arc striking section is made of iron; the upper arc striking piece conductive section and the upper arc striking piece arc striking section are connected by a solder layer; A moving contact plate for cooperating with the upper arc-striking piece is provided in front of the upper arc-striking piece, and a contact portion for contacting the upper arc-striking piece is provided on the moving contact plate; the moving contact plate is made of copper-iron-phosphorus alloy.

2. The miniature circuit breaker according to claim 1, characterized in that: The contact portion is a convex block integrally formed on the moving contact plate.

3. The miniature circuit breaker according to claim 1, characterized in that The arc-striking section of the upper arc-striking piece is provided with a static contact portion that cooperates with the contact portion.

4. The miniature circuit breaker according to claim 3, characterized in that: The static contact portion is made of the same material as the moving contact plate, and the static contact portion is welded on the arc-striking section of the upper arc-striking piece.

5. The miniature circuit breaker according to claim 1, characterized in that The conductive segment of the upper arc-striking piece includes a straight portion, an end of the straight portion is bent to one side to form a bent portion, and an end of the bent portion is provided with a connecting portion for connecting to the arc-striking segment of the upper arc-striking piece.

6. The miniature circuit breaker according to claim 1, characterized in that: The arc-striking segment of the upper arc-striking piece includes a static contact portion, one end of which is provided with a first bending portion for connecting with the conductive segment of the upper arc-striking piece, and the other end of the static contact portion is provided with a second bending portion.

7. The miniature circuit breaker according to claim 1, characterized in that The solder layer is a copper solder layer.

8. The miniature circuit breaker according to claim 1, characterized in that: A lower arc-striking piece for cooperating with the moving contact plate is further provided below the moving contact plate in the housing; the lower arc-striking piece is connected to the arc extinguishing chamber.

9. The miniature circuit breaker according to claim 1, characterized in that: The moving contact plate is connected to a transmission mechanism, and the transmission mechanism is used to control the closing and opening of the small circuit breaker.

10. The miniature circuit breaker according to claim 1, characterized in that The moving contact plate is made of CuFe0.1P alloy.

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