CN106898530B

CN106898530B - Arc extinguisher and safe distribution equipment

Info

Publication number: CN106898530B
Application number: CN201610818429.0A
Authority: CN
Inventors: E.库恩; W.莱特尔
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2015-09-16
Filing date: 2016-09-12
Publication date: 2020-01-17
Anticipated expiration: 2036-09-12
Also published as: TR201611854A2; DE102015217704A1; CN106898530A

Abstract

The arc extinguisher (10) has a switching contact (12) and an arc extinguishing chamber (20), the switching contact itself having a fixed contact (13) and a moving contact (14) which moves relative to it. The arc extinguisher has a guide rail (23) and a winding (30), the first end of the guide rail is arranged in the arc extinguishing chamber area, the second end of the guide rail is arranged in the front chamber area (21), the winding is electrically connected with the second end of the guide rail, and the winding is electrified after the arc (11) is transferred from the moving contact to the guide rail. The coil has a first section (31) which is arranged laterally to the switching contact in order to press the arc in the direction of the arc chute after the switching thereof. The coil has a second section (32) which is arranged at least partially between the arc chute and a broad side (4) of the housing of the safety switching device in order to attract the arc towards the arc chute after the switching thereof. By energizing the turns, an electromagnetic force is exerted on the arc which expels the arc in the direction of the arc chute, the first section squeezing the arc in this direction and the second section attracting the arc in this direction. Due to this design, a greater force is exerted on the arc, as a result of which the switching capacity of the arc extinguisher is significantly improved.

Description

Arc extinguisher and safe distribution equipment

Technical Field

The invention relates to an arc extinguisher for extinguishing an arc of an electromechanical safety distribution device, in particular a line protection switch or a circuit breaker. The invention also relates to an electromechanical safety switching device having such an arc extinguisher.

Background

Different safety power distribution devices are known from the prior art. Circuit breakers are specially designed for high currents. Line protection switches (so-called LS switches) are overcurrent protection devices used in electronic devices, which are used in particular in the field of low-voltage networks. The line protection switch is also referred to as "Miniature Circuit Breaker" (MCB) in english technical books. Circuit breakers and line protection switches ensure reliable opening in the event of a short circuit and protect the user and prevent overloading of electrical equipment, for example, to prevent damage to the circuit due to excessive heating caused by excessive currents. Circuit breakers and line protection switches are used in power supply networks, in particular as switches and safety elements, and for monitoring and protecting circuits.

The safety switching device is electrically conductively connected to the cable of the circuit to be monitored via two cable connections in order to interrupt the current flow in the cable if required. For this purpose, the safety switching device has switching contacts, including stationary contacts which are fixed in position and moving contacts which can be moved relative to the stationary contacts. The moving contact can be connected to a safety switching deviceSo that the switch contacts can be opened and closed. In this way, when a predetermined condition occurs, such as a short circuit or an overcurrent, the switching contact is opened in order to isolate the monitored circuit from the supply network. Such a safety switching device is also referred to as a series arrangement in the field of low-voltage technology

And are known, for example, from the publications DE60209126T2 or EP1939912B 1.

If the switch contacts are opened at the moment when current is flowing through them, an arc is formed between the fixed contact and the moving contact when the switch contacts are opened. In order to extinguish this arc, conventional safety power distribution devices have at least one so-called arc chute into which the arc is introduced, in order to be able to extinguish the arc there as quickly as possible. For this purpose, the arc extinguishing chamber has a plurality of arc extinguishing plates arranged side by side and spaced apart from one another. If an arc is driven into the arc chute, it is divided into a plurality of partial arcs when it impinges on the arc plates, which then burn between the arc plates. Due to the partial arcing of a plurality of such circuits connected in series, high arc voltages are generated, which lead to a tearing arc and thus to a rapid extinction of the arc. Therefore, low energy can be kept in the arc extinguishing chamber, and the power distribution capacity (Schaltleistung) or the current interruption capacity of the safety power distribution equipment can be improved

A safety switching device with such an arc extinguishing chamber is known, for example, from the publication DE3311052a 1.

Heat removal from safety switchgear is problematic in small installations, since the energy input in this installation, caused by the burning arc, leads, due to the limited installation space, to a drastic temperature rise inside the safety switchgear housing, which can lead to damage to the components of the safety switchgear. Since the thermal energy generated by the arc is difficult to dissipate into the environment, efforts are made to keep the burning time of the arc as short as possible and thus to add as little energy as possible to the safety switchgear. In order to be able to design the safety power distribution device as compact as possible, further improvements in the power distribution capacity of the safety power distribution device are required in order to reduce the energy input in the device and thus the temperature in the housing.

Disclosure of Invention

The object of the invention is therefore to provide an arc extinguisher and a safety switchgear assembly, which are characterized by improved power distribution capacity while avoiding the problems described in detail above.

The above-mentioned object is solved by an arc extinguisher and an electromechanical safety power distribution device with an arc extinguisher according to the invention.

The arc extinguisher according to the invention has a switching contact and an arc extinguishing chamber, the switching contact itself comprising a fixed contact and a moving contact which moves relative to it. The arc extinguisher furthermore has a guide rail, the first end of which is arranged in the area of the arc extinguishing chamber and the second end of which is arranged in the front chamber area, and a winding, which is electrically conductively connected to the second end of the guide rail, wherein the winding is not energized until the arc is transferred from the moving contact to the guide rail. The coil has a first section which is arranged laterally to the switching contact in order to press the arc in the direction of the arc chute after its switching. The coil has a second section, which is arranged at least partially between the quenching chamber and the broad side of the housing of the safety switching device in order to attract the arc towards the quenching chamber after its switching.

By applying current through the conductor turns, an electromagnetic force is exerted on the arc, which displaces the arc in the direction of the arc chute, in order to extinguish the arc there. In other words: the electrical coil can be energized in such a way that it exerts an electromagnetic force on the arc in order to push it towards the arc chute in the energized state, i.e. after the arc has been transferred onto the guide rail. The first section of the winding presses the arc out of the front chamber area in the direction of the arc extinguishing chamber, in other words: the first segment exerts a magnetic repulsion force on the arc. On the other hand, the arrangement of the wire turns at least partially in the second section between the arc chute and the broad side of the safety switching device housing draws the arc out of the front-space region in the direction of the arc chute, in other words: the second segment has a magnetic attraction on the arc. Overall, a greater force is exerted on the arc on the basis of this design, so that the arc can be extinguished more quickly. This can significantly improve the power distribution capacity of the arc extinguisher.

In addition, it can also be advantageous if the second section based on the conductor turns is arranged in the region between the quenching chamber and the broad side of the safety switching device housing, so that the arc is held stable in the quenching chamber until it is quenched, thereby avoiding the arc repeatedly exiting from the quenching chamber and re-entering the quenching chamber again. The conductor turns are also connected to the circuit in such a way that they are only energized when the arc is transferred to the guide rail. This significantly reduces the heat generation of the safety power distribution device during "normal operation" compared to a continuously energized coil. As a result, due to the lower thermal load within the safety switchgear, lower thermodynamic requirements are also placed on the materials used, so that a more cost-effective structure can be achieved. In addition, the high internal resistance of the safety switching device, which is present only after switching, causes a limited effect of the current on the short-circuit current to be switched off, so that even higher switching capacities can be achieved by this effect.

The switching contacts of the installed safety switchgear are usually contacted in such a way that the fixed contacts are electrically conductively connected to the input terminals of the safety switchgear and the moving contacts are electrically conductively connected to the output terminals of the safety switchgear.

The term "front chamber area" refers to that area of space which is situated in front of the arc chute and below the switch contact area. The term "arc quenching turns (Blasschleife)" is sometimes used instead of the term "turns". The term "switching" refers to the jumping of the arc from the moving contact to the rail when the switch contacts are opened. Since the current is only supplied by the arc transition to the conductor track, the power loss of the safety switching device can be kept low in the "normal" state, i.e. in the current supply state when the switching contacts are closed.

Furthermore, the term "arc chute" is to be understood broadly. This is understood to mean, in the first place, a conventional arc extinction chamber, which has a plurality of extinguishing plates arranged next to one another and spaced apart from one another. If the arc is pushed into the arc chute, it splits into a plurality of partial arcs as it impinges on the arc plates, which then burn between the arc plates. Due to the partial arcing of a plurality of such circuits connected in series, high arc voltages are generated, which lead to a tearing arc and thus to a rapid extinction of the arc. The term "arc chute" is also understood to mean, among other things, a so-called plastic arc chute which has little or no ferromagnetic components and thus provides no "self-propulsion" on the arc, which is usually achieved by ferromagnetic materials (generally steel) and corresponding geometric designs (for example, V-section arc plates).

In an advantageous embodiment of the arc extinguisher, the wire turns are designed in one piece. In this way, the winding can be produced at low cost, since the assembly effort is eliminated in comparison with a multipart embodiment.

In a further advantageous embodiment, the arc extinguisher has a ferromagnetic element which is arranged next to the second section of the winding between the arc extinguishing chamber and the broad side of the safety switchgear housing. By means of the ferromagnetic element, the electromagnetic action of the second section of the turns on the arc is increased, which leads to a further acceleration of the arc in the direction of the arc chute, thus leading to a more rapid extinguishing of the arc and thus to a further improvement of the distribution capacity.

In a further advantageous embodiment of the safety switching device, a second section of the winding is arranged on both sides of the quenching chamber, and the two second sections are electrically conductively connected to one another at least at one end. By means of this further second section of the turns, the electromagnetic action of the turns on the arc is further enhanced, which results in a further acceleration of the arc in the direction of the arc chute, thus resulting in a more rapid extinguishing of the arc and thus in a further improvement of the distribution capacity.

In a further advantageous embodiment of the safety switching device, a ferromagnetic element is arranged on each side of the interrupter chamber. By means of this further ferromagnetic element, the electromagnetic action of the arc extinguisher on the arc is further enhanced, which leads to a further acceleration of the arc in the direction of the arc extinguishing chamber, thus leading to a more rapid extinguishing of the arc and thus to a further improvement of the distribution capacity.

The electromechanical safety device according to the invention has a housing which itself has a front side, a fastening side opposite the front side, and a narrow side and a wide side connecting the front side and the fastening side. The safety equipment also has an arc extinguisher of the type described above, which is mounted and fixed in the housing of the safety equipment. The advantages of the electromechanical safety device according to the invention with which the arc extinguisher according to the invention is mounted and fixed in its housing can be seen in the advantages of the arc extinguisher according to the invention which have already been explained in detail above.

In an advantageous embodiment of the safety device, the housing is designed as a housing made of an insulating material. In this context, it is to be understood that the housing is made of an electrically insulating material, for example plastic.

In a further advantageous embodiment of the safety equipment, the housing has a width of a distributor unit (teilkingseinheit). By realizing an equipment enclosure with a width equal to the distribution unit of 18mm, the arc extinguisher can be arranged in a conventional stringing equipment with a standard width of 18 mm. The arc extinguisher according to the invention can therefore also be used in standard series installations of compact design, whereby the distribution capacity is likewise significantly improved without the housing width being changed.

Drawings

Two embodiments of the arc extinguisher are described in detail below with reference to the accompanying drawings. In the drawings:

fig. 1A to 1C schematically show a first embodiment of an arc extinguisher in a first switching state;

fig. 2A to 2C schematically show the first embodiment of the arc extinguisher in a second switching state; and

fig. 3A and 3B schematically show a second embodiment of an arc extinguisher.

Like parts are designated with like reference numerals throughout the different views. This description applies to all figures in which corresponding parts are also visible.

Detailed Description

Fig. 1A to 1C show schematically in different views a first exemplary embodiment of an arc extinguisher 10, which is in a first switching state. Fig. 1B schematically illustrates a side view of the arc extinguisher 10. Fig. 1A shows a lower side view corresponding thereto. In this view, it is clearly apparent that the arc extinguisher 10 has two parallel broad sides 4 opposite one another and two narrow sides 3 arranged orthogonally thereto, likewise parallel to one another and opposite one anotherAnd (4) boundary. Due to the compact design, such an arc extinguisher 10 is also suitable for compact series installations with only one distribution unit width B (approximately 18mm)

Is used in the preparation of the medicament.

The first switching state is characterized in that the switching contact 12 of the arc extinguisher 10, which is composed of the fixed contact 13 and the moving contact 14 that can be moved relative thereto, is closed, so that a current I can flow through the switching contact 12. Fig. 1B schematically shows the corresponding current path 8, through which the current I passes through the arc extinguisher 10, by means of a plurality of arrows: the current I flows through the input connection (not shown) of the safety equipment via the magnet coil 2 to the fixed contact 13 and, with the switching contact 12 closed, through the moving contact 14 to the output connection 9 of the safety switchgear. The arc extinguisher 10 also has an arc extinguishing chamber 20 in order to extinguish the arc 11 (see fig. 2B) formed when the switching contact 12 is opened. A so-called front chamber region 21 (indicated by a dashed line) is situated between the arc chute 20 and the switching contact 12. The arc extinguisher 10 also has a guide rail 23, the first end 23-1 of which is arranged below the extinguishing chamber 20 and the second end 23-2 of which protrudes into the front chamber area 21.

If the switching contact 12 is opened by the moving contact 14 moving away from the fixed contact in the energized state, an arc 11 is first formed between the fixed contact 13 and the moving contact 14, so that a current is kept flowing through the switching contact 12 by the arc 11. If the moving contact 14 moves further away from the fixed contact 13, the arc voltage is increased continuously as a function of the increasing distance until the arc 11 is transferred from the moving contact 14, i.e. jumps onto the guide track 23. More precisely, the arc 11 jumps onto the second end 23-2 of the guide rail 23, which is arranged below the switching contact 12 in the front chamber region 21. The arc 11 which is burnt between the feeler 24 and the guide rail 23 is guided in the direction of the arc extinguishing chamber 20 by the guide rail 23 and the feeler 24 which is located below the fixed contact 13 and is electrically conductively connected thereto, via a further guide rail 26 which is electrically conductively connected to the feeler 24 and the fixed contact 13. The arc chute 20 is designed here as a conventional arc chute with a plurality of arc plates 22 arranged side by side and spaced apart from one another. If the arc 11 is driven from the front chamber region 21 in the direction of the arc chute 20, it is divided into a plurality of partial arcs when it impinges on the arc plates 22, which then burn between the respective arc plates 22 and the further guide rail 26. Due to the partial arcs of several such circuits connected in series, high arc voltages are generated, which ultimately lead to a tearing of the arc 11 and thus to an extinction of the arc 11.

In order to further improve the power distribution capacity of the arc extinguisher 10, the arc 11 is pushed more rapidly in the direction of the arc extinguishing chamber 20 and is thus extinguished more rapidly. For this purpose, the arc extinguisher 10 has a winding 30, which is electrically conductively connected to the second end 23-2 of the guide rail 23 and is energized only after the arc 11 has been transferred from the moving contact 14 to the guide rail 23. The coil 30 has a first section 31, which is electrically conductively connected to the second end 23-2 of the rail 23 and is arranged laterally to the switching contact 12 in order to press the arc 11 in the direction of the arc chute 20 after it has been transferred from the front-chamber region 21. A second section 32 of the winding 30 is connected to the first section 31, which is arranged at least partially between the arc chute 20 and the broad side 4 of the safety switching device housing in order to attract the arc 11 towards the arc chute 20 after it has been transferred from the front-chamber region 21.

Since the direction of the current in the first section 31 of the winding 30 is oriented opposite to the direction of the current in the arc 11, a repulsive electromagnetic force is generated on the arc 11. Conversely, the current direction in the second section 32 is oriented parallel to the current direction of the arc 11, thereby producing an attractive electromagnetic force on the arc 11. Overall, due to this design of the winding 30, a double force action is produced on the arc 11, which forces the arc 11 more rapidly from the front chamber region in the direction of the arc chute 20. By the described more rapid entry of the arc 11 into the arc chute 20, the power distribution capacity of the arc extinguisher 10 is significantly improved.

Fig. 1C also shows a detail of the winding 30 corresponding to that shown in fig. 1A and 1B. For clarity of the view, arc chute 20 is not present in this view. The turns 30 are designed in one piece here, but it is likewise possible to design the turns 30 to consist of several parts. Furthermore, the coil turns 30 can be either planar, i.e. flat, or curved, so that they are adapted to the spatial conditions in the front chamber 21. It can be formed here, for example, as a stamped and bent part, as a wire profile with different cross-sectional shapes, or also as a pliable component, for example a strand. It is likewise possible to arrange the turns 30, in particular the second section 32 thereof, not only on one side between the quenching chamber 20 and the broad housing side 4, but on both sides between the quenching chamber 20 and each of the two broad housing sides 4. For this purpose, the turn 30 must have two second sections 32, which are electrically connected to each other, either in series or in parallel.

Fig. 2A to 2C show schematically in corresponding views a first exemplary embodiment of an arc extinguisher 10 in a second switching state, which is different from the first one. Fig. 2B still schematically shows a side view of the arc extinguisher 10. Fig. 2A shows a lower side view corresponding thereto. Fig. 2C again schematically shows a detail of the now energized turns 30 corresponding to that shown in fig. 2A and 2B.

The second switching state is characterized in that the switching contact 12 of the arc extinguisher 10 is now open. An arc 11 is formed which first burns between the fixed contact 13 and the moving contact 14. At this point, current I continues to flow via switch contact 12. If the moving contact 14 moves further away from the fixed contact 13, the arc voltage increases further until the arc 11 is transferred from the moving contact 14 to the second end 23-2 of the guide rail 23. This state, in which the arc 11 has been transferred and is between the second end 23-2 of the guide rail 23 and the antenna 24, is shown in fig. 2B. The current path 8, which is again schematically indicated by a plurality of arrows, extends from the input connection of the safety switching device, via the field coil 2 and the fixed contact 13 to the antenna 24, from there via the arc 11 to the second end 23-2 of the guide rail 23 and further via the now energized conductor turns 30 to the output connection 9. During the further arc extinction, the arc 11 is pushed in the direction of the arc extinguishing chamber 20 and there burns first between the guide rail 23, the respective arc plate 22 and the further guide rail 26. Fig. 2A shows this state.

Fig. 2C shows the current path through the energized turns 30 at two different times, wherein the arc 11 is also shown at two different times. To indicate these two different states/moments, the arc is indicated by the reference numerals 11-1 and 11-2 in the figure. Fig. 2C first shows the arc 11-1 directly after the arc transition: the arc 11-1 is now between the antenna 24 and the second end 23-2 of the guide rail 23. In this case the current path 8 extends via the arc 11-1 to the second end 23-2 and via the turns 30 connected to this second end 23-2 to the output connection 9. In the front chamber 21, in which the arc 11-1 is present at this moment, the direction of the current through the arc 11-1 and the direction of the current in the first section 31 of the coil 30 are oriented opposite to each other. Since the oppositely directed currents repel one another, an electromagnetic force F1 is exerted on the arc 11-1, which presses the arc 11-1 in the direction of the quenching chamber 20.

At a second, slightly later point in time, which is shown in fig. 2C, the arc 11 is already in the region of the arc chute 20 (see fig. 2B), the arc chute 20 not being shown in the view of fig. 2C for the sake of clarity of the view. In this case the current path 8 extends through the further guide rail 26 and the arc 11-2 to the first end 23-1 of the guide rail 23, further through the guide rail 23 to its second end 23-2 and further via the turns 30 connected to this second end 23-2 to the output connection 9. At this point in time the direction of current through the arc 11-2 and the direction of current in the second segment 31-2 of the coil 30 are oriented parallel to each other. Since the currents in the same direction attract each other, an electromagnetic force F2 is exerted on the arc 11-2, which attracts the arc 11-2 towards the extinguishing chamber 20 or retains it inside the extinguishing chamber 20, in order to prevent its exit from the extinguishing chamber 20.

With this design, the force action on the arc 11 is significantly increased, which forces the arc 11 in the direction of the arc chute 20, as a result of which the arc 11 enters the arc chute 20 more rapidly and thus a more rapid extinguishing of the arc is achieved. The arc extinguisher capacitance and thus the distribution capacity of the safety distribution equipment is significantly improved.

Fig. 3A and 3B schematically illustrate a second embodiment of the arc extinguisher 10. In this case, a ferromagnetic element 35 is additionally provided in the region of the second section 32 of the coil 30, which ferromagnetic element serves to intensify the electromagnetic force of the second section 32 on the arc 11-2. The ferromagnetic element 35, which is not electrically conductively connected to the wire turns 30, is preferably arranged inside the wire turns 30 between the arc chute 20 and the broad side 4. It is advantageous to intensify the electromagnetic force action of the second section 32 on the arc 11-2, in particular when the current is less than 1000 a, since in this case the electromagnetic force generated by the turns 30 on the arc 11 is often not sufficient to push the arc 1 smoothly into the arc chute 20 and to hold it there.

Furthermore, the arrangement of the second section 32 of the winding 30 at least partially between the quenching chamber 20 and the broad side 4 also offers the possibility of providing an additional outlet channel 25 in this region, through which hot gases resulting from the arc 11 can be conducted away from the safety power distribution system. Thereby reducing the pressure level inside the arc chute 20 during the extinguishing of the arc 11, which contributes to an easier entry and a more stable retention of the arc 11 inside the arc chute 20.

List of reference numerals

2 field coil

3 narrow side

4 broad side

8 current path

9 output connector

10 arc extinguisher

11 arc of electricity

12 switch contact

13 fixed contact

14 moving contact

20 arc extinguishing chamber

21 antechamber area

22 arc extinguishing piece

23 guide rail

24 antenna

25 outlet channel

26 another guide rail

30 turns

31 first section

32 second segment

35 ferromagnetic element

I current

Width B

F1 and F2 forces

Claims

1. An arc extinguisher (10) for extinguishing an arc (11) for an electromechanical safety distribution device, comprising

-a switch contact (12) having a fixed contact (13) and a moving contact (14) moving relative to the fixed contact,

-an arc extinguishing chamber (20),

-a guide rail (23) which is provided with a first end in the region of the arc chute (20) and with a second end in a front chamber region (21), wherein the front chamber region (21) is a spatial region in front of the arc chute (20) and below the switching contact (12),

-a turn (30) which is electrically conductively connected to a second end of the guide rail (23),

wherein the conductor loop (30) is not energized until after the arc (11) has been transferred from the moving contact (14) to the guide rail (23), wherein the conductor loop (30) has a first section (31) which is arranged laterally to the switching contact (12) in order to press the arc (11) after its transfer in the direction of the arc chute (20), and wherein the conductor loop (30) has a second section (32) which is not located in the front-chamber region (21) but is arranged at least partially between the arc chute (20) and the broad side (4) of the housing of the safety switching device in order to attract the arc (11) after its transfer in the direction of the arc chute (20) and to hold the arc stably in the arc chute until it is extinguished, wherein the housing of the electromechanical safety switching device has a width (B) of a distribution unit which is equal to 18 mm.

2. Arc extinguisher (10) according to claim 1, characterized in that the turns (30) are designed in one piece.

3. Arc extinguisher (10) according to claim 1 or 2, characterized in that the arc extinguisher (10) has a ferromagnetic element (35) which is arranged beside the second section (32) of the turn (30) between the arc chute (20) and the broad side (4) of the housing of the safety power distribution equipment.

4. Arc extinguisher (10) according to claim 1 or 2, characterized in that a second section (32) of the turns (30) is provided on each side of the arc extinguishing chamber (20), said second sections being conductively connected to each other at least at one end.

5. An arc extinguisher (10) according to claim 3, characterized in that a ferromagnetic element (35) is provided on each side of the arc extinguishing chamber (20).

6. An electromechanical safety distribution device comprises

A housing having a front side, a fastening side opposite the front side, and a narrow side (3) and a wide side (4) connecting the front side and the fastening side,

-an arc extinguisher (10) according to any one of claims 1 to 5, mounted and fixed within the housing.

7. An electromechanical safety distribution device according to claim 6, characterized in that the housing is designed as a housing of insulating material.

8. An electromechanical safety power distribution device according to claim 6 or 7, wherein the electromechanical safety power distribution device is a line protection switch or a circuit breaker.