EP3577675B1

EP3577675B1 - Single-stage circuit breaker

Info

Publication number: EP3577675B1
Application number: EP18702694.3A
Authority: EP
Inventors: Chang Chun Hu; Jean-Mary Martel; Shou Qi XU
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2017-02-04
Filing date: 2018-02-01
Publication date: 2022-08-17
Anticipated expiration: 2038-02-01
Also published as: WO2018141866A1; CN108400066A; EP3577675A1; CN108400066B

Description

Technical Field

The present invention relates to a low-voltage circuit breaker, and more particularly to a single-stage circuit breaker.

Background

As we all know, the low-voltage circuit breaker is a switch appliance which can not only connect and disconnect a normal-load current and an overload current, but also can connect and disconnect a short-circuit current. In addition to a control function, the low-voltage circuit breaker further has, in a circuit, some protection functions, such as overload, short circuit, under-voltage and leakage protection.
For example, the miniature circuit breaker, referred to as MCB for short, is the most widely used terminal protection appliance in building electrical terminal power distribution devices, and can provide short circuit, overload, over-voltage and other line protection. As another example, the residual current device, referred to as RCD for short, having over-current protection, can quickly cut off the fault power in a short time to protect the safety of people and electrical equipment, playing the function of overload, short circuit and leakage protection.
The arc fault detection device, referred to as AFDD for short, is also an electric line protection device, and the main function thereof is to detect and identify a dangerous grounding arc fault, a parallel arc fault and a series arc fault, and to drive an action of a device for disconnecting the current in a timely manner, so as to prevent the occurrence of electrical fire. Using embedded system digital circuit control and an original arc characteristics recognition algorithm, the advantages of small size and strong function are achieved, and a leakage current protection function is integrated, so that automatic monitoring and protection of fault arc and leakage current are achieved, effectively guaranteeing the safety of low-voltage power distribution lines and electrical equipment as well people.
In order to better meet the diverse requirements for line protection, there is a need to design a new low-voltage circuit breaker which combines the several line protection functions possessed by the MCB, RCD, and AFDD together while maintaining a relatively compact structural layout, and this undoubtedly poses a great challenge to the design of this new circuit breaker product.
A single-stage circuit breaker with the features of the first part of claim 1 is known from US 2015/068881 A1 . Further prior art is disclosed by EP 2 840 587 A1 .

Summary of the Invention

An object of the present invention is to provide a single-stage circuit breaker, which can not only meet the requirements for arc fault detection, leakage protection and overload over-current protection at the same time, but also can ensure the compactness of the internal structural layout of the circuit breaker.
The object is met by a single-stage circuit breaker of claim 1. Preferred embodiments are disclosed in the dependent claims.
The present invention provides a single-stage circuit breaker, comprising a shell comprising a first housing, a second housing and a mounting housing located therebetween, a first accommodation chamber being formed between the first housing and the mounting housing, and a second accommodation chamber being formed between the second housing and the mounting housing; an electromagnetic trip device arranged in the first accommodation chamber; a first contact assembly and a first execution assembly used for cooperating with the electromagnetic trip device and located at one side of the first accommodation chamber; an arc extinguishing device accommodated between the electromagnetic protection device and the first contact assembly; a thermal protection and arc fault detection device located near the arc extinguishing device and in the first accommodation chamber; an arc fault and leakage trip device arranged in the second accommodation chamber; a second contact assembly and a second execution assembly used for cooperating with the arc fault and leakage trip device and located at one side of the second accommodation chamber; and a circuit board assembly for arc fault handling and leakage protection, wherein the first execution assembly and the second execution assembly move simultaneously with an operating handle via a common driving member.
In a further exemplary embodiment of the single-stage circuit breaker, the single-stage circuit breaker has a first current path and a second current path, the first current path being located in the first accommodation chamber, and the second current path being located in the second accommodation chamber.
In the single-stage circuit breaker, the circuit board assembly comprises a first circuit board and a second circuit board, wherein the first circuit board is accommodated in the first accommodation chamber, and the second circuit board is accommodated in the second accommodation chamber, in order to better achieve the compactness of the internal structure of the circuit breaker.
In the single-stage circuit breaker, the single-stage circuit breaker further comprises an auxiliary contact assembly, which is arranged inside the second accommodation chamber for effecting safe electrical isolation of the circuit board assembly, thereby improving the safety and reliability of the entire circuit breaker.
In the single-stage circuit breaker, one end of the auxiliary contact assembly is electrically connected to the second circuit board, and the other end of the auxiliary contact assembly can be disconnected from or connected to the second contact assembly.
In another exemplary embodiment of the single-stage circuit breaker, the first circuit board and the second circuit board are arranged in parallel to each other and at least partially overlap in a vertical direction.
In another exemplary embodiment of the single-stage circuit breaker, the first circuit board and the second circuit board can be integrated as a whole.
In another exemplary embodiment of the single-stage circuit breaker, the single-stage circuit breaker further comprises a multi-function button module arranged at a side portion of the shell for state displaying and function testing of the single-stage circuit breaker.
In another exemplary embodiment of the single-stage circuit breaker, the single-stage circuit breaker further comprises a snap rail connection assembly arranged at an end portion of the shell for detachably connecting the single-stage circuit breaker to a corresponding snap rail, in order to increase the flexibility and reliability of the installation thereof.
In another exemplary embodiment of the single-stage circuit breaker, the shell has a width of 18 mm.

Brief Description of the Drawings

The present invention is described in detail below in conjunction with the accompanying drawings and particular embodiments. In the accompanying drawings:

Fig. 1 is a schematic diagram of the external structure of a single-stage circuit breaker according to an embodiment of the present invention;
Fig. 2 is a schematic structural diagram of an L pole of the single-stage circuit breaker in Fig. 1;
Fig. 3 is a schematic structural diagram of an N pole of the single-stage circuit breaker in Fig. 1;
Fig. 4 is a schematic diagram of six-view orthogonal configurations of the single-stage circuit breaker in Fig. 1; and
Fig. 5 is a schematic exploded structural diagram of the single-stage circuit breaker in Fig. 1.

Description of Reference Numerals:

First execution assembly 11	Arc fault and leakage trip device 23
Multi-function button module 12	L- pole terminals 14, 19
Electromagnetic trip device 13	N- pole terminals 24, 29
Arc extinguishing device 15	Second contact assembly 26
First contact assembly 16	Movable contact 27
Thermal protection and arc	Stationary contact 28
fault detection device 17
Circuit board assembly 18	Driving member 31
First circuit board 181	Operating handle 32
Second circuit board 182	Auxiliary contact assembly 50
Locking member 20	First housing 41
Sliding member 30	Second housing 42
Second execution assembly 21	Mounting housing 43

Detailed Description

In order to more clearly understand the technical features, objectives and effects of the present invention, the specific embodiments of the present invention are described with reference to the accompanying drawings, and in the drawings, the same reference numerals denote the same parts. In the accompanying drawings, which represent various embodiments, the same last two digits denote structurally identical or structurally similar but functionally identical components.
In order to make the figures concise, the parts relevant to the present invention are merely shown illustratively in the figures, and they do not represent the actual structure as a product. In addition, in order to make the figures concise and easy to be understood, in some figures, there are components of the same structure or function, and only one therein is drawn illustratively or only one therein is marked.
The words "up", "down", "front", "rear", "left", "right", etc. herein are merely used to indicate the positional relationship between related parts, but not to limit their absolute positions.
The words "first", "second", etc. herein are merely used for distinguishing each other rather than representing the degree of importance and order, etc. thereof.
The words "parallel", "vertical", etc. are not strictly mathematical and/or geometrical limitations, and also contain errors that can be understood by a person skilled in the art and are permissible during manufacturing or usage, etc.
Reference is made to Fig. 1, which shows a schematic structural diagram of a single-stage circuit breaker of an embodiment of the present application.
Specifically, the single-stage circuit breaker comprises a shell. The shell comprises a first housing 41, a second housing 42, and a mounting housing 43 located therebetween. A first accommodation chamber is formed between the first housing 41 and the mounting housing 43. A second accommodation chamber is formed between the second housing 42 and the mounting housing 43. The single-stage circuit breaker has a first current path and a second current path, wherein the first current path is located in the first accommodation chamber, and the second current path is located in the second accommodation chamber.
Further, referring to Figs. 2-4, the single-stage circuit breaker further comprises an electromagnetic trip device 13, a first contact assembly 16, a first execution assembly 11, an arc extinguishing device 15, a thermal protection and arc fault detection device 17, an arc fault and leakage trip device 23, a second contact assembly 26, a second execution assembly 21, a circuit board assembly 18, and an auxiliary contact assembly 50. The first execution assembly 11 and the second execution assembly 21 move simultaneously with an operating handle 32 via a common driving member 31.
Specifically, as shown in Fig. 2, the electromagnetic trip device 13 is arranged in the first accommodation chamber, and the first contact assembly 16 and the first execution assembly 11 are used for cooperating with the electromagnetic trip device 13 and are located at one side of the first accommodation chamber, for effecting over-current protection of the circuit breaker. The arc extinguishing device 15 is accommodated between the electromagnetic protection device 13 and the first contact assembly 16, in order to facilitate the rapid extinction of the arc. The thermal protection and arc fault detection device 17 is arranged near the arc extinguishing device 15 and located in the first accommodation chamber. The thermal protection and arc fault detection device 17 is used for realizing overload protection of the circuit breaker and can detect an arc fault in a timely manner and then perform a tripping action.
As shown in Fig. 3, the arc fault and leakage trip device 23 is arranged in the second accommodation chamber, and the second contact assembly 26 and the second execution assembly 21 are used for cooperating with the arc fault and leakage trip device 23 and are located at one side of the second accommodation chamber, for effecting leakage protection and arc fault protection of the circuit breaker.
Further, the first execution assembly 16 and the second execution assembly 21 move simultaneously with an operating handle 32 via a common driving member 31. Therefore, the first execution assembly 11 and the second execution assembly 21 can be respectively actuated by the action of the handle 32, and then the first contact assembly 16 and the second contact assembly 26 are respectively actuated. An L-pole main switch formed between a movable contact and a stationary contact in the first contact assembly 16 serves to control the connection and disconnection of an L-pole main loop. An N-pole main switch formed between a stationary contact and a movable contact in the second contact assembly 26 serves to control the connection and disconnection of an N-pole main loop.
It is to be noted that the circuit board assembly 18 of the present application can be used for realizing both arc fault handling and leakage protection functions at the same time. With reference to Fig. 4, according to a preferred embodiment of the present application, the circuit board assembly 18 comprises a first circuit board 181 and a second circuit board 182, wherein the first circuit board 181 is accommodated in the first accommodation chamber, and the second circuit board 182 is accommodated in the second accommodation chamber, in order to better achieve the compactness of the internal structure of the circuit breaker.
Still further, the single-stage circuit breaker further comprises an auxiliary contact assembly 50 arranged inside the second accommodation chamber for effecting safe electrical isolation of the circuit board assembly. By means of the design above, it is possible for the circuit board assembly to be in a relatively safe voltage level, preventing the possibility of over-voltage breakdown, and further enhancing the service life of the circuit board assembly. Therefore, there is no need to use the circuit board with specific specifications to meet reliability requirements of the product thereof, and a commonly configured circuit board assembly can be used to meet safety performance requirements and thus greatly reduces the cost of the entire product.
As a preferred embodiment, one end of the auxiliary contact assembly 50 is electrically connected to the second circuit board 182, and the other end of the auxiliary contact assembly 50 can be disconnected from or connected to the second contact assembly 26. The presence of the auxiliary contact assembly 50 is equivalent to the addition of an auxiliary switch between the circuit board assembly 18 and a right-hand wiring terminal. This allows a current loop on the board assembly 18 to be independent of the L-pole main loop and the N-pole main loop, respectively. When the circuit breaker is in an ON state, an L-pole main switch and an N-pole main switch are in a switching-on state, the auxiliary switch is also in a switching-on state, and the circuit breaker works normally. It is to be noted that when the circuit breaker is in an OFF state, the L-pole main switch and the N-pole main switch are in a switching-off state, and the auxiliary switch is also in a switching-off state, so that the circuit board assembly 18 is electrically isolated dually. Therefore, by controlling the switching on/off of the auxiliary switch, the circuit board assembly 18 can be safely and electrically isolated and the circuit board assembly 18 can be effectively prevented from being always in an energized state, so as to effectively reduce the risk of damaging the circuit board assembly 18 by over-voltage breakdown, thereby improving the safety and reliability of the whole circuit breaker.
According to a preferred embodiment, the first circuit board 181 and the second circuit board 182 are arranged in parallel to each other and at least partially overlap in a vertical direction. It is to be understood that, as an optional embodiment, the first circuit board 181 and the second circuit board 182 can also be integrated as a whole.
Preferably, the single-stage circuit breaker further comprises a multi-function button module 12 arranged at a side portion of the shell for state displaying and function testing of the single-stage circuit breaker.
Preferably, the single-stage circuit breaker further comprises a snap rail connection assembly arranged at an end portion of the shell for detachably connecting the single-stage circuit breaker to a corresponding snap rail, in order to increase the flexibility and reliability of the installation thereof. As shown in Figs. 2 and 3, the snap rail connection assembly further comprises a locking member 20 and a sliding member 30. As an optional embodiment, the shell has a width of 18 mm.
The circuit breaker of the present application can better meet various requirements for line protection, and can not only combine various line protection functions such as detection of leakage, over-current and disconnection and fault detection possessed by the MCB, RCD and AFDD, but also can maintain a relatively compact structural layout, thereby effectively guaranteeing the safety of low-voltage power distribution lines and electrical equipment as well as people.
As used herein, the term "exemplary" means "serving as an instance, example, or description", and any "exemplary" illustration and embodiment herein should not be interpreted as a more preferred or a more advantageous technical solution.

Claims

A single-stage circuit breaker, comprising
a shell comprising a first housing (41), a second housing (42), and a mounting housing (43) located therebetween, a first accommodation chamber being formed between the first housing (41) and the mounting housing (43), and a second accommodation chamber being formed between the second housing (42) and the mounting housing (43) ;

an electromagnetic trip device (13) arranged in the first accommodation chamber;

a first contact assembly (16) and a first execution assembly (11) cooperating with the electromagnetic trip device (13) and located at one side of the first accommodation chamber;

an arc extinguishing device (15) accommodated between the electromagnetic protection device (13) and the first contact assembly (16);

a thermal protection and arc fault detection device (17) located near the arc extinguishing device (15) and in the first accommodation chamber;

an arc fault and leakage trip device (23) arranged in the second accommodation chamber;

a second contact assembly (26) and a second execution assembly (21) cooperating with the arc fault and leakage trip device (23) and located at one side of the second accommodation chamber; and

a circuit board assembly (18) for arc fault handling and leakage protection,
wherein an L-pole main switch is formed between a movable contact and a stationary contact in the first contact assembly (16),
wherein an N-pole main switch is formed between a stationary contact and a movable contact in the second contact assembly (26),
wherein the first execution assembly (11) and the second execution assembly (21) move simultaneously with an operating handle (32) via a common driving member (31), so that the first execution assembly (11) and the second execution assembly (21) are respectively actuated by the action of the handle (32), and then the first contact assembly (16) and the second contact assembly (26) are respectively actuated,

characterized in that

the circuit board assembly (18) comprises a first circuit board (181) and a second circuit board (182), wherein the first circuit board (181) is accommodated in the first accommodation chamber, and the second circuit board (182) is accommodated in the second accommodation chamber, wherein an auxiliary contact assembly (50) is arranged inside the second accommodation chamber, one end of the auxiliary contact assembly (50) being electrically connected to the second circuit board (182) and the other end of the auxiliary contact assembly (50) being disconnectable from or connectable to the second contact assembly (26), the auxiliary contact assembly (50) being equivalent to the addition of an auxiliary switch, wherein, when the single-stage circuit breaker is in an ON state, the L-pole main switch and the N-pole main switch are in a switching-on state, the auxiliary switch is also in a switching-on state,

wherein, when the circuit breaker is in an OFF state, the L-pole main switch and the N-pole main switch are in a switching-off state, and the auxiliary switch is also in a switching-off state.
The single-stage circuit breaker of claim 1, wherein the single-stage circuit breaker has a first current path and a second current path, the first current path being located in the first accommodation chamber, and the second current path being located in the second accommodation chamber. 3
The single-stage circuit breaker of claim 1 or 2, wherein the first circuit board (181) and the second circuit board (182) are arranged in parallel to each other and at least partially overlap in a vertical direction.
The single-stage circuit breaker of claim 1 or 2, wherein the first circuit board (181) and the second circuit board (182) can be integrated as a whole.
The single-stage circuit breaker of any of claims 1 to 4, further comprising a multi-function button module (12) arranged at a side portion of the shell for state displaying and function testing of the single-stage circuit breaker.
The single-stage circuit breaker of any of claims 1 to 5, further comprising a snap rail connection assembly arranged at an end portion of the shell for detachably connecting the single-stage circuit breaker to a corresponding snap rail.
The single-stage circuit breaker of any of claims 1 to 6, wherein the shell has a width of 18 mm.