Miniature electric leakage protection circuit breaker

Abstract

The utility model relates to a miniature electric leakage protection circuit breaker, which comprises a shell, an L-line circuit breaker unit and an N-line electric leakage protection unit, and is characterized in that the shell comprises a seat body, a first cover body and a second cover body, and a circuit breaker cavity for placing the L-line circuit breaker unit is formed between the first cover body and the seat body; an earth leakage protection cavity used for placing an N-line earth leakage protection unit is formed between the second cover body and the seat body. The N-line electric leakage protection unit comprises an N-line contact frame, an N-line moving contact, a first wiring terminal, an N-line static contact, an electric leakage protection tripping mechanism, a second wiring terminal, a wire, a circuit board arranged in the base body, and a zero sequence mutual inductor which is sleeved on the wire and is electrically connected with the circuit board, and an arc extinguishing groove is arranged in the base body corresponding to a static contact point of the N-line static contact. And the seat body is provided with an exhaust hole communicated with the arc extinguishing groove. The utility model has the advantages of simple structure, stable and reliable performance, convenient assembly and small volume.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit breakers, in particular to a small leakage protection circuit breaker. Background Art

[0002] At present, small circuit breakers, also known as miniature circuit breakers, are suitable for overload and short-circuit protection of AC 50 / 60Hz rated voltage 230 / 400V and rated current not exceeding 125A lines. They can also be used for infrequent operation conversion of lines under normal circumstances. Small circuit breakers are mainly used in various places such as industry, commerce, high-rise and residential buildings. Small leakage circuit breakers are switches that can automatically operate when the leakage current in the circuit exceeds a predetermined value, which can protect the safety of people and electrical appliances. Small leakage circuit breakers include multiple L-line circuit breaker units and N-line leakage protection modules assembled with multiple L-line circuit breaker units. The internal structure layout of the existing leakage protection circuit breaker is unreasonable, resulting in a large volume of the leakage protection circuit breaker, and the structural design of the N-line leakage protection module of the small leakage circuit breaker is relatively complex, and the assembly is relatively cumbersome, and the arc extinguishing performance of the L-line leakage protection module is poor, and there is a defect of weak breaking capacity. Summary of the invention

[0003] The utility model aims to overcome the defects of the prior art and provide a small leakage protection circuit breaker with simple structure, stable and reliable performance, convenient assembly and small size.

[0004] To achieve the above-mentioned purpose, the utility model adopts a small leakage protection circuit breaker, including a shell, an L-line circuit breaker unit, and an N-line leakage protection unit. The shell includes a base, a first cover body arranged on one side of the base, and a second cover body arranged on the other side of the base. A circuit breaker cavity for placing the L-line circuit breaker unit is formed between the first cover body and the base, and a leakage protection cavity for placing the N-line leakage protection unit is formed between the second cover body and the base. The N-line leakage protection unit includes an N-line contact that cooperates with the operating mechanism of the L-line circuit breaker unit. The invention relates to a frame, an N-line moving contact linked to the N-line contact frame, a first wiring terminal arranged in a base body, an N-line static contact electrically connected to the first wiring terminal and matched with the N-line moving contact, a leakage protection tripping mechanism arranged in the base body, a second wiring terminal arranged in the base body, a wire connected between the N-line moving contact and the second wiring terminal, a circuit board arranged in the base body, and a zero-sequence mutual inductor sleeved on the wire and electrically connected to the circuit board, an arc extinguishing groove is arranged at the static contact point of the N-line static contact in the base body, and an exhaust hole connected to the arc extinguishing groove is arranged on the base body.

[0005] The beneficial effects of the above structure are as follows: The N-line leakage protection unit adopts a modular structure design, so that the modular assembly of the N-line leakage protection unit and the housing can be realized. Moreover, the structure design of the N-line leakage protection unit is more compact, with a smaller volume and more convenient assembly. And the static contact of the N-line static contact is arranged in the arc extinguishing groove, and the high-pressure gas in the arc extinguishing groove can be quickly discharged from the exhaust hole, so that the air flow blows the arc, making it cool and stretch in the air flow, so as to achieve the purpose of extinguishing the arc, and the arc extinguishing performance of the N-line leakage protection unit can be effectively improved. Therefore, this small leakage protection circuit breaker has the advantages of simple structure, stable and reliable performance, convenient assembly and small volume.

[0006] Particularly, a plurality of gas-producing convex strips are respectively arranged in the arc extinguishing groove, and a plurality of gas-producing grooves are formed between the plurality of gas-producing convex strips, and the plurality of gas-producing grooves communicate between the static contact and the exhaust hole. The gas-producing convex strips generate gas under the action of the arc, and the arc is blown by the gas, making it cool and stretch in the air flow, so as to achieve the purpose of extinguishing the arc. Therefore, it is beneficial to improve the arc extinguishing performance of the N-line leakage protection unit.

[0007] Particularly, a tension spring is arranged between the N-line moving contact and the seat body. One end of the N-line moving contact has a hook-shaped body, one end of the tension spring is connected to the hook-shaped body, the other end of the tension spring is connected to the positioning rod in the seat body, a limiting convex part is arranged on the N-line moving contact corresponding to one side of the hook-shaped body, and a limiting groove matched with the limiting convex part is arranged on the N-line contact holder. The tension spring can increase the contact pressure between the N-line moving contact and the N-line static contact, so as to ensure more reliable contact between the N-line moving contact and the N-line static contact.

[0008] Particularly, a positioning groove matched with the N-line moving contact is arranged on the N-line contact holder. One end of the N-line moving contact extends into the positioning groove, a positioning pin is arranged on the N-line contact holder, and the N-line moving contact is rotatably arranged on the positioning pin. The positioning groove of the N-line contact holder plays a positioning role for the N-line moving contact, and can ensure more compact connection between the N-line contact holder and the N-line moving contact.

[0009] Particularly, one end of the N-line static contact has a contact part extending into the arc extinguishing groove, the static contact is arranged on the contact part, and the other end of the N-line static contact is inserted into the first wiring terminal. The contact part of the N-line extends into the arc extinguishing groove, which is beneficial to improving the arc extinguishing performance of the N-line leakage protection unit, and the N-line static contact is inserted into the first wiring terminal, which is convenient for the assembly of the N-line static contact and the first wiring terminal, and the assembly is more convenient. Description of the Drawings

[0010] Figure 1 It is a three-dimensional view of an embodiment of the present invention.

[0011] Figure 2This is an exploded view of an embodiment of the utility model.

[0012] Figure 3 It is the front view of the internal structure of the embodiment of the utility model.

[0013] Figure 4 This is an assembly diagram of the N-line contact frame and the N-line moving contact according to an embodiment of the utility model. DETAILED DESCRIPTION

[0014] like Figures 1 to 4 As shown, the embodiment of the utility model is a small leakage protection circuit breaker, including a housing 10, an L-line circuit breaker unit 11, and an N-line leakage protection unit 20. The housing 10 includes a base 101, a first cover 102 arranged on one side of the base 101, and a second cover 103 arranged on the other side of the base 101. A circuit breaker cavity for placing the L-line circuit breaker unit 11 is formed between the first cover 102 and the base 101, and a leakage protection cavity 100 for placing the N-line leakage protection unit 20 is formed between the second cover 103 and the base 101. The N-line leakage protection unit 20 includes an N-line contact frame 21 that cooperates with the operating mechanism of the L-line circuit breaker unit 11, and a contact frame 21 that is arranged in linkage with the N-line contact frame 21. An N-line moving contact 22 on the head frame 21, a first terminal 23 arranged in the base body 101, an N-line static contact 24 electrically connected to the first terminal 23 and matched with the N-line moving contact 22, a leakage protection tripping mechanism 25 arranged in the base body 101, a second terminal 26 arranged in the base body 101, a wire 27 connected between the N-line moving contact 22 and the second terminal 26, a circuit board 28 arranged in the base body 101, and a zero-sequence transformer 29 sleeved on the wire 27 and electrically connected to the circuit board 28, an arc extinguishing groove 1000 is arranged at the static contact point 241 of the N-line static contact 24 in the base body 101, and an exhaust hole 1001 connected to the arc extinguishing groove 1000 is arranged on the base body 101. The arc extinguishing groove 1000 is provided with a plurality of gas-generating convex strips 104, and a plurality of gas-generating grooves 1041 are formed between the plurality of gas-generating convex strips 104, and the plurality of gas-generating grooves 1041 are connected between the static contact 241 and the exhaust hole 1001. The gas-generating convex strips generate gas under the action of the arc, and the arc is blown by the gas, so that the arc is cooled and elongated in the air flow, thereby achieving the purpose of extinguishing the arc. This is conducive to improving the arc extinguishing performance of the N-line leakage protection unit.

[0015] like Figure 2 , 4As shown, a tension spring 30 is provided between the N-line moving contact 22 and the base body 101. One end of the N-line moving contact 22 has a hook-shaped body 221. One end of the tension spring 30 is connected to the hook-shaped body 221, and the other end of the tension spring 30 is connected to the positioning rod 105 inside the base body 101. A limiting protrusion 222 is provided on the N-line moving contact 22 at a side corresponding to the hook-shaped body 221, and a limiting groove 211 that cooperates with the limiting protrusion 222 is provided on the N-line contact holder 21. The tension spring can increase the contact pressure between the N-line moving contact and the N-line static contact, thereby ensuring a more reliable contact between the N-line moving contact and the N-line static contact. A positioning groove 212 that cooperates with the N-line moving contact 22 is provided on the N-line contact holder 21. One end of the N-line moving contact 21 extends into the positioning groove 212. A positioning pin 31 is provided on the N-line contact holder 21, and the N-line moving contact 22 is rotatably arranged on the positioning pin 31. The positioning groove of the N-line contact holder plays a positioning role for the N-line moving contact, ensuring a more compact connection between the N-line contact holder and the N-line moving contact. One end of the N-line static contact 24 has a contact portion 242 extending into the arc extinguishing groove 1000. The static contact point 241 is provided on the contact portion 242, and the other end of the N-line static contact 24 is inserted into the first wiring terminal 23. The contact portion of the N-line extends into the arc extinguishing groove, which is beneficial to improving the arc extinguishing performance of the N-line leakage protection unit. Moreover, the N-line static contact is inserted into the first wiring terminal, facilitating the assembly of the N-line static contact and the first wiring terminal, and the assembly is more convenient.

[0016] The N-line leakage protection unit adopts a modular structure design, enabling modular assembly of the N-line leakage protection unit and the housing. Moreover, the structural design of this N-line leakage protection unit is more compact, with a smaller volume and more convenient assembly. The static contact point of the N-line static contact is arranged in the arc extinguishing groove, and the high-pressure gas in the arc extinguishing groove can be quickly discharged from the exhaust hole. Thus, the airflow blows the arc, causing it to cool and elongate in the airflow, thereby achieving the purpose of extinguishing the arc, effectively improving the arc extinguishing performance of the N-line leakage protection unit. Therefore, this small leakage protection circuit breaker has the advantages of simple structure, stable and reliable performance, convenient assembly, and small volume.

Claims

1. A miniature leakage protection circuit breaker, characterized in that: It includes a housing, an L-line circuit breaker unit, and an N-line leakage protection unit. The housing includes a base body, a first cover body disposed on one side of the base body, and a second cover body disposed on the other side of the base body. A circuit breaker cavity for placing the L-line circuit breaker unit is formed between the first cover body and the base body, and a leakage protection cavity for placing the N-line leakage protection unit is formed between the second cover body and the base body. The N-line leakage protection unit includes an N-line contact holder that is linked and cooperated with the operating mechanism of the L-line circuit breaker unit, an N-line moving contact linked and arranged on the N-line contact holder, a first terminal disposed in the base body, an N-line static contact electrically connected to the first terminal and cooperating with the N-line moving contact, a leakage protection tripping mechanism disposed in the base body, a second terminal disposed in the base body, a wire connected between the N-line moving contact and the second terminal, a circuit board disposed in the base body, and a zero-sequence current transformer sleeved on the wire and electrically connected to the circuit board. An arc extinguishing groove is provided at the static contact point corresponding to the N-line static contact in the base body, and an exhaust hole communicating with the arc extinguishing groove is provided on the base body.

2. The miniature residual current operated circuit breaker according to claim 1, wherein: Multiple gas-producing ridges are respectively provided in the arc extinguishing groove, and multiple gas-producing grooves are formed between the multiple gas-producing ridges. The multiple gas-producing grooves communicate between the static contact point and the exhaust hole.

3. The miniature leakage protection circuit breaker according to claim 1 or 2, characterized in that: A tension spring is provided between the N-line moving contact and the base body. One end of the N-line moving contact has a hook-shaped body. One end of the tension spring is connected to the hook-shaped body, and the other end of the tension spring is connected to a positioning rod in the base body. A limiting protrusion is provided on the N-line moving contact at the side corresponding to the hook-shaped body, and a limiting groove cooperating with the limiting protrusion is provided on the N-line contact holder.

4. The miniature leakage protection circuit breaker according to claim 1 or 2, characterized in that: A positioning groove cooperating with the N-line moving contact is provided on the N-line contact holder. One end of the N-line moving contact extends into the positioning groove, and a positioning pin is provided on the N-line contact holder. The N-line moving contact is rotatably arranged on the positioning pin.

5. The miniature residual current operated circuit breaker according to claim 1 or 2, characterized in that: One end of the N-line static contact has a contact portion extending into the arc extinguishing groove, and the static contact point is provided on the contact portion. The other end of the N-line static contact is inserted into the first terminal.

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