EP2747107B1 - Electric switching device - Google Patents

Description

The invention relates to an electrical switching device, such. a contactor, which comprises a housing and at least two switching chambers within the housing with contacts for interrupting at least one current path. Each switching chamber is an arc quenching device for erasing arcs that can form when opening the contacts provided. Furthermore, at least one guide channel is provided within the housing, which deflects the arc gases emerging from the arc quenching device in the direction of at least one exhaust opening for the exit of the arc gases from the housing.

Such a switching device is eg from the US Pat. No. 6,388,867 B1 known. There, a circuit breaker is described which has a hood assembly to direct arc gases from the housing. An arc that occurs between opening contacts of a contact pair of the disconnector is deleted within a housing of the circuit breaker. During the duration of the arc, arc gases of high pressure and high ionization emerge emerging from openings in an upper wall of the housing. Here, the openings of a plurality of switching chambers of different current paths are arranged side by side. The openings are covered by a common hood, which forms a channel to two exhaust ports facing away from each other. Here, all the openings lead into the channel, which is formed by the hood. Thus, the highly ionized arc gases are led out or blown out of the housing to two sides.

Switchgear can generate a significant amount of arc gases in interrupting large currents and voltages. The arc gases are usually blown out through the top or back of the switchgear. Typically, electrical switching devices comprise a plurality of current paths (poles), so that in particular in the event of a short circuit there is the risk that transverse short circuits may occur when blowing out arc gases in the vicinity of a connection contact of a current path. This is in the switching device according to the US Pat. No. 6,388,867 B1 thereby prevents the arc gases are blown out on sides of the housing, which are the connection contacts of the current paths are arranged as far away as possible.

Basically, there is a requirement for electrical switching devices that in a short circuit, the switching device is still intact and cross shorts between different current paths (poles) of the switching device are avoided. Measures against the destruction of the housing of the switching device are the choice of suitable switching chamber materials and their wall thicknesses and the selection of suitable pressure relief openings or blow-off, in particular in the case of short circuit outgoing from the arc, blow out explosive arc gases. Controlling especially short circuit currents in DC applications is made difficult by the fact that in this case no natural zero crossing occurs, which would promote a permanent interruption of the circuit via a rapid arc quenching. Especially with very compact switching devices short distances are present, which can be easily electrically bridged by highly ionized arc gases and can lead to cross-short circuits. In the case of switching devices of very compact design, transverse shorts between different contact pairs can therefore occur if, in the event of a short circuit, highly ionized arc gases leave the outlet openings from the housing and bridge various switching chambers over them.

An electrical switching device according to the preamble of the claim is known from FR2 511 188 known.

The object of the present invention is to provide an electrical switching device which has increased safety against transverse short circuits.

The object is achieved by an electrical switching device according to claim 1.

Each switching chamber is thus provided with a guide channel for guiding arc gases to an exhaust opening, wherein the guide channels of different switching chambers are separated from each other. The arc gases of different switching chambers are therefore not brought together immediately after emerging from an arc quenching device, but initially performed separately within the housing to the exhaust openings. Thus, the distance between the different switching chambers, which would have to be bridged for a cross-short between the switching chambers, increased. The probability of cross-shorting is therefore reduced. Another positive effect is that the arc gases are further cooled and deionized as they pass through the guide channels until the arc gases of two switching chambers meet, further reducing the likelihood of cross-shorting.

The switching device generally has end faces on which connection contacts for the current paths (poles) of the switching device are provided. Two opposite end faces of the switching device are connected to each other via usually running at right angles to these longitudinal sides. The blow-out openings are preferably provided in the longitudinal sides, preferably in one of the longitudinal sides, in order to avoid that the arc gases are blown out in the region of the connection contacts.

On a, usually perpendicular to the end faces and perpendicular to the longitudinal sides arranged top of the housing auxiliary switches are arranged as a rule, so that a blowing of arc gases on this side is also undesirable.

The guide channels can also be arranged such that the arc gases of at least two switching chambers of different current paths are deflected to exhaust openings on opposite sides of the housing.

In a first preferred embodiment, the switching device has a plurality of current paths, each with double interrupting switches, wherein the arc gases of two current paths arranged adjacent to one another are blown out on different sides of the housing. Alternatively it can be provided that the arc gases of the two pairs of contacts of a double interrupting switch a current path on different sides of the Be blown housing, wherein the outlet openings are arranged alternately on different sides of the housing in a plurality of switching paths.

Each guide channel can be divided into a plurality of, preferably parallel, sub-channels. As a result, a channeled guidance of the arc gases is effected. Furthermore, the ribbing associated with the arrangement of a plurality of subchannels leads to an additional stiffening of the guide channel. This is particularly advantageous if the guide channels are integrated into a side wall of the housing. The housing stability is thereby increased.

In order to ensure as long as possible guide paths within the housing, the guide channels are arranged such that a deflection of the arc gases is effected by about 90 degrees. As a result, arc gases, which are usually blown perpendicular to a side wall of the housing from the arc quenching devices, deflected in a direction parallel to the side wall of the housing. Thus, the guide channels can be integrated into the respective side wall.

Figur 1

eine perspektivische Darstellung zweier elektrischer Schaltgeräte;

Figur 2

zwei Strombahnen der Schaltgeräte gemäß Figur 1;

Figur 3

einen Querschnitt eines der Schaltgeräte gemäß Figur 1 durch eine Schaltkammer;

Figur 4

eine Lichtbogentreiberanordnung eines Schaltgeräts gemäß Figur 1;

Figur 5

eine Deckelhälfte eines Schaltgeräts gemäß Figur 1;

Figur 6

den Deckel eines der Schaltgeräte gemäß Figur 1 mit Schaltkammern;

Figur 7

eine zweite Ausführungsform des Deckels eines Schaltgeräts gemäß Figur 1 und

Figur 8

eine dritte Ausführungsform eines Deckels eines Schaltgeräts gemäß Figur 1.

Preferred embodiments will be explained in more detail below with reference to the drawings. Hereby shows:

FIG. 1

a perspective view of two electrical switching devices;

FIG. 2

two current paths of the switching devices according to FIG. 1 ;

FIG. 3

a cross section of one of the switching devices according to FIG. 1 through a switching chamber;

FIG. 4

a Lichtbogentreiberanordnung a switching device according to FIG. 1 ;

FIG. 5

a cover half of a switching device according to FIG. 1 ;

FIG. 6

the cover of one of the switching devices according to FIG. 1 with switching chambers;

FIG. 7

a second embodiment of the lid of a switching device according to FIG. 1 and

FIG. 8

a third embodiment of a lid of a switching device according to FIG. 1 ,

FIG. 1 shows two juxtaposed electrical switching devices in the form of two contactors 1, 2, wherein in the following the contactor 1, which in the illustration according to FIG. 1 shown at the front, is described as an example for both contactors 1, 2. The contactor 1 comprises a housing 3, which has a housing lower part 4 and an upper housing part 5. The upper housing part 5 is closed by a cover with a first cover half 6 and a second cover half 7.

The two cover halves 6, 7 form an upper side 8 of the housing 3, which faces away from the housing lower part 4. At the end face on the narrow surfaces, the cover halves 6, 7 form end faces 9, 10, which face away from one another, wherein, in the case of contactors 1, 2 arranged next to one another, as in FIG FIG. 1 illustrated, the end faces 9, 10 of the adjacent contactors 1, 2 are arranged in pairs on the same page.

The upper housing part 5 forms two longitudinal sides 11, 12 of the housing 3, wherein two longitudinal sides 11, 12 of two juxtaposed contactors 1, 2 are opposite. The upper housing part 5 forms a step 23 on one of the longitudinal sides 11, on which a connection module 13 is provided. With adjacent contactors 1, 2, the connection module 13 is one of the two contactors 1, 2 between two longitudinal sides 11, 12 of the two contactors 1, 2. The longitudinal sides 11, 12 of the two contactors 1, 2 are thus always spaced from each other.

In a first longitudinal side 11 of the two longitudinal sides 11, 12, both the first cover half 6 and the second cover half 7 exhaust openings 14, 15, which serve to lead out arc gases from the housing 3 and blow out.

The contactor 1 is a two-pole contactor 1 with two parallel current paths, wherein in a first end face 9 of the two end faces 9, 10 Kontaktöffhungen 18, 19 are provided, via which connection contacts 16, 17, which are located within the housing 3, accessible are. The connection contacts 16, 17 are each connection contacts a current path, which run parallel to the longitudinal sides 11, 12 through the housing 3. On the second end face, not shown here, which faces away from the first end face 9, there are identically designed connection openings with connection contacts located therein. The connection contacts 16, 17 are formed in the form of terminals which can be reached and actuated via screw openings 20, 21 located in the cover halves 6, 7 with a screwdriver in order to be able to connect the connection contacts 16, 17 to current-conducting elements. In principle, however, other electrical switching devices with more than two poles can be provided.

In the housing upper part 5, the current paths are arranged, wherein each current path comprises a switch with contact pairs in order to be able to interrupt the current path electrically. This arcing can occur between the contacts of a contact pair, which are guided through the exhaust ports 14, 15 out of the housing 3. Each contact pair is a switching chamber with an arc quenching device, as will be explained in more detail below, is provided. The switches can be actuated by a magnetic drive, which is located in the lower housing part 4.

The lower housing part further has a mounting recess 22 with which the contactor 1 can be mounted on a mounting rail.

FIG. 2 shows the first current path 24 and the second current path 25, which in the housing according to FIG. 1 are arranged. The current paths 24, 25 each have a first terminal contact 16, 17 and then each extend to a second terminal contact 26, 27. About the terminal contacts 16, 17, 26, 27, the current paths 24, 25 with a circuit, preferably a DC Circuit, be connected. In the following, representative of both current paths 24, 25, the first current path 24 is described in detail.

Between the two connection contacts 17, 27 of the first flow path 24, a switch 28 is provided. This comprises a first contact pair 29 and a second contact pair 30. The first connection contact 17 leads to the first contact pair 29. The second connection contact 27 leads to the second contact pair 30. Both contact pairs 29, 30 are in the housing of the contactor in separate, mutually electrically insulated Switching chambers arranged.

The first connection contact 17 is electrically connected to a contact carrier in the form of a fixedly held fixed contact carrier 33, on which a first contact 31 of the first contact pair 29 is arranged. A second contact 36 of the first contact pair 29 is arranged to be movable relative to the first contact 31. The second contact 36 is in the in FIG. 2 shown vertically adjustable. The second contact 36 is provided on an electrically conductive contact carrier in the form of a bridge contact piece 35, which is adjustable via a switching bridge, not shown here. In an on state, the first contact 31 and the second contact 36 are held in contact with each other. In an in FIG. 2 illustrated off state, the first contact 31 and the second contact 36 are kept out of contact with each other.

The second connection contact 27 is connected to a contact carrier in the form of a further fixedly held fixed contact carrier 34. On the further fixed contact carrier 34, a further first contact 32 of the second contact pair 30 is arranged. For this, a further second contact 37 is movably held, which is also arranged on the bridge contact piece 35 and with the first contact 32 of the second contact pair 30 in or out of contact can be transferred. By adjusting the bridge switching piece 35 thus both pairs of contacts are opened or closed simultaneously.

When transferring the bridge contact piece 35 into an open position, arcs can form between the contacts 31, 32, 36, 37 of the contact pairs 29, 30, which arcs must be extinguished. For this purpose, on the respective second contact 36, 37 side facing away from the first contacts 31, 32 each have a quenching device, said arcs are passed through hereinafter explained in more detail track assemblies per contact pair 29, 30 in the respective extinguishing device.

FIG. 3 shows a cross section through the housing according to FIG. 1 by a switching chamber in which the second contact pair 30 according to FIG. 2 is arranged. There, it can be seen that for guiding an arc, which forms between the first contact 32 and the second contact 37, a first track arrangement 41 and a second track arrangement 42 are provided. The first rail arrangement 41 serves to guide an arc with a first current direction into an arc-extinguishing device 43, which is located on the side of the second contact 37 facing away from the first contact 32 is located within the switching chamber 49. The second track arrangement 42 serves to guide an arc with a second current direction into the same arc quenching device 43.

The first track arrangement 41 is represented by a first track rail 44 and a second track rail 46. The second track arrangement 42 is shown, comparable to the first track arrangement 41, by a first track 45 and a second track 47. The two first rails 44, 45 extend in opposite directions from the first contact 32 and lead to the arc quenching device 43, which they receive between them. The two first rails 44, 45 are connected to each other at the ends remote from the first contact 32 via a connecting bracket 48. Thus, the two first rails 44, 45 form a closed ring or a closed loop surrounding the second contact pair 30. The second rails 46, 47 extend in opposite directions from the second contact 37 and are on the side facing away from the first contact 32 side of the second contact 37 a closed rail ring 40 forming interconnected.

In principle, the first rails 44, 45 and second rails 46, 47 need not be looped together or annularly connected to each other. Other designs of the rails 44, 45, 46, 47 are also conceivable.

The first track rail 44 of the first track assembly 41 extends in FIG. 3 considered first to the left and then 90 degrees deflected upward, with the distance between the first track 44 and the second track 46 increases successively. The arc is therefore formed between these two rails 44, 46 further and is driven by the second contact pair 30 in a first direction of flow to the left and then upwards. In the further course of the arc is at the side facing away from the first contact 32 back of the bridge contact piece 35 along, wherein the arc is successively driven into gaps between individual quenching plates 50 of the arc quenching device 43. On an upper side of the arc-extinguishing device 43, outlet openings 51 are provided in order to blow out the arc gases generated by the arc from the switching chamber 49 and the arc-extinguishing device 43. The second track arrangement 42 is mirror-symmetrical to the first track arrangement 41 built up.

Due to the formation of several partial arcs between the quenching plates 50 and the cooling effect, an arc will lose so much energy in the quenching device in the form of a deion quenching chamber that the driving voltage is reached very quickly and the arc extinguishes. For an arc of higher energy content, e.g. in a highly inductive circuit, it may happen that the arc after entering the arc quenching device 43 has lost only a portion of its energy and the individual partial arcs between the quenching plates 50 under the effect of a permanent magnetic Blasfeldes the arc quenching device in full width. The arc can then run back towards the second contact pair 30. After "passing through" the second contact pair 30, the arc can then again run along the track assembly in the direction of the arc quenching device 43. If there is sufficient residual energy, several cycles may occur until the arc has lost enough energy to extinguish it. Although the arc voltage drops after passing through the arc quenching device 43 and the subsequent passage through the second contact pair 30 again, but this short-term drop in voltage does not affect so much by the continuous, rapid movement of the arc. When re-entering the arc quenching device 43, the arc voltage increases again, so that the arc is finally safely deleted.

In FIG. 3 is also apparent that outlet openings 51 are provided, which lead from the arc quenching device 43 to a guide channel 61 which is formed in the first cover half 6 of the upper housing part 5 and has a first longitudinal side 11 of the housing 3 provided exhaust opening 14. Here, the arc gases in the in FIG. 3 shown orientation of the housing 3 from a vertically upward discharge direction from the outlet openings 51 deflected in a 90 degree angled horizontal to the right blow-out direction, as indicated by the arrows.

The closed design of the rails 44, 45, 46, 47 in the form of loops also has the advantage that in the in FIG. 3 considered plane the switching chamber 49 upwards, downwards and on both sides through the rails 44, 45, 46, 47 is sealed off and stabilized.

In order to be able to move arcs, which form between the contacts of the contact pairs, in the direction of the arc quenching device, an arc runner arrangement 52 according to FIG FIG. 4 intended. There are two arc drive assemblies 52, 52 'arranged side by side, which are designed in mirror image to each other and are used together for one of the switches. In the following one of the two arc drive arrangements 52 will be explained by way of example. This comprises an outer pole element 53 and inner pole element 54. The two pole elements 53, 54 each have mutually parallel base webs 55, 56, each of which a pole plate 57, 58 projects at right angles. The two pole plates 57, 58 of the two pole elements 53, 54 are likewise arranged parallel to one another. The inner pole member 54 is made smaller in size than the outer pole member 53, so that the inner pole member 54 can be disposed within the outer pole member 53. Between the two base webs 55, 56, which are spaced from each other, a permanent magnet 59 is arranged. Thus, a magnetic field with at least approximately parallel magnetic field lines forms between the two pole plates 57, 58. Between the two pole plates 57, 58, the contacts of one of the contact pairs are arranged.

The base webs 55, 56 have a plurality of openings 60, which serve the arcs formed in the respective switching chamber through the outlet openings according to FIG. 3 to let escape.

FIG. 5 shows the second cover half 7 of the contactor 1 according to FIG. 1 , The second cover half 7 has on the upper side 8 a housing wall 64 in which guide channels are formed by a plurality of mutually parallel partial channels 62. The sub-channels 62 are formed by ribs 63 pointing inwards towards the interior of the housing. The sub-channels 62 each lead to an exhaust opening 15 on the first longitudinal side 11. The sub-channels 62 are open towards the inside of the housing and point to the base webs of the respective arc runner assembly and are covered by the arc guide assemblies inwardly, so that at least approximately closed sub-channels 62 result. Several subchannels 62 may each have one Form guide channel for the arc gases of a switching chamber. In this case, the apertures in the arc runner assemblies each aligned with one or more of the sub-channels 62. The sub-channels 62 are parallel to a joining edge 65 of the second cover half 7, on which the first cover half according to FIG. 1 abuts. The cover halves are both constructed identically with respect to the sub-channels 62, so that it is clear that the sub-channels 62 of the second cover half 7 are separated from the sub-channels of the first cover half 6. In addition, individual sub-channels 62 of a cover half, individually or together, form a guide channel, wherein each guide channel is separated from the other guide channels by the ribs 63, so that the arc gases emanating from different contact pairs are not mixed within the housing 3.

FIG. 6 shows a part of the upper housing part 5 with the first cover half 6 and the second cover half 7. In these are the current paths 24, 25 with their switches 28 and the contact pairs 29, 30. Further, the track assemblies, in particular the respective first track rail 44, recognizable and the arc-extinguishing device 43. The arc-bus driver assembly 52 is constructed approximately as in FIG FIG. 4 shown, the two in FIG. 4 shown separate arc drive assemblies 52 in FIG. 6 are integrally formed, so that not, as in FIG. 4 , but two U-shaped inner pole member 54 and a U-shaped outer pole member 53. Otherwise, the arc runner assemblies 52 are according to their FIG. 4 educated.

FIG. 6 shows a switching bridge 39, which is located within the housing lower part according to FIG. 1 is located and there is adjustable via a magnetic drive. At the switching bridge 39 are the bridge switching pieces 35 of both current paths 24, 25, so that all pairs of contacts 29, 30 of all switches 28 open or close within the housing 3 simultaneously.

It can be seen that the openings 60 of the arc runner arrangements 52 open into partial channels 62 of the housing halves 6, 7, so that arc gases from the switching chambers 49 are deflected within the housing wall 64 of the respective cover half 6, 7 and directed to the exhaust openings 14, 15. The arc gases are thus exclusively on the in FIG. 6 blown out front longitudinal side shown, not on the side facing away from this second longitudinal side. By the in FIG. 5 illustrated ribs 63 are the Partial channels 62 separated from each other, each with a plurality of juxtaposed sub-channels form a guide channel.

FIG. 7 shows an arrangement according to FIG. 6 , wherein it can be seen that the outlet openings 14 are arranged in the first cover half 6 on the first longitudinal side 11. The outlet openings 15 of the second cover half 7 are arranged on the first longitudinal side 11 facing away from the second longitudinal side 12. Thus, the arc gases are each a switch 28 having two pairs of contacts 29, 30 and thus two switching chambers 49 blown out to one side of the housing and the arc gases of the other switch blown to a diametrically opposite other side of the housing.

Alternatively, like FIG. 8 illustrated, be provided that each switch 28, the arc gases of the two pairs of contacts 29, 30 are blown out to different sides of the housing.

LIST OF REFERENCE NUMBERS

1

contactor

2

contactor

3

casing

4

Housing bottom

5

Housing top

6

first lid half

7

second lid half

8th

top

9

first end face

10

second end face

11

first longitudinal side

12

second long side

13

connection module

14

exhaust vent

15

exhaust vent

16

first connection contact

17

first connection contact

18

Koritaktöffnung

19

Koritaktöffnung

20

screw opening

21

Schraubenöffuung

22

mounting recess

23

step

24

first current path

25

second current path

26

second connection contact

27

second connection contact

28

switch

29

first contact pair

30

second contact pair

31

first contact

32

first contact

33

Fixed contact carrier

34

Fixed contact carrier

35

Bridging contact member

36

second contact

37

second contact

38

Gantry ring

39

jumper

40

Gantry ring

41

first track arrangement

42

second track arrangement

43

Arc quenching device

44

first track

45

first track

46

second track

47

second track

48

connecting brackets

49

switching chamber

50

splitter

51

outlet opening

52

Arc driver arrangement

53

outer pole element

54

inner pole element

55

base web

56

base web

57

pole plate

58

pole plate

59

permanent magnet

60

breakthrough

61

guide channel

62

subchannel

63

rib

64

housing wall

65

joining edge

Claims (8)

1. Electrical switching device (1) comprising a housing, at least two switching chambers (49) within the housing (3) with contacts (31, 32, 36, 37) for interrupting at least one current path (24, 25), an arc extinguishing device (43) for each switching chamber (49) and at least one guide channel (61) within the housing (3) which redirects the arc gases escaping from the arc extinguishing device (43) in the direction of at least one exhaust opening (14, 15) to allow the arc gases to exit from the housing (3), wherein a guide channel (61) is provided for each switching chamber (49), wherein the guide channels (61) of the different switching chambers (49) are separate from one another, wherein the housing (3) comprises end faces (9, 10) with electrical connections (16, 17, 26, 27) for at least one current path (24, 25) switchable by means of the contacts (31, 32, 36, 37), wherein the exhaust openings (14, 15) are provided in side faces of the housing (3) which are different from the end faces (9, 10), characterised in that the guide channels (61) redirect the arc gases of at least two switching chambers (49) to exhaust openings on opposite sides of the hosing (3).
2. Electrical switching device according to claim 1, characterised in that the guide channels (61) redirect the arc gases of at least two switching chambers (49) of different current paths (24, 25) to the exhaust openings on opposite sides of the housing (3).
3. Electrical switching device according to claim 1, characterised in that the guide channels (61) redirect the arc gases of at least two switching chambers (49) of the same current paths (24, 25) to the exhaust openings on opposite sides of the housing (3).
4. Electrical switching device according to any one of the preceding claims, characterised in that the housing (3) has an upper side (8) for the attachment of auxiliary switches, wherein the exhaust openings (14, 15) are provided in side faces of the housing (3), which are different from the upper side (8).
5. Electrical switching device according to any one of the preceding claims, characterised in that the guide channels (61) are divided into a plurality of preferably parallel part channels (62).
6. Electrical switching device according to any one of the preceding claims, characterised in that the guide channels (61) cause a deviation of the arc gases by approximately 90 degrees.
7. Electrical switching device according to any one of the preceding claims, characterised in that the guide channels (61) are integrated into a side wall of the housing (3).
8. Electrical switching device according to any one of the preceding claims, characterised in that a step (23) is formed on a longitudinal side (11), on which a connection module (13) is provided so that the connection module of one of the two switching devices with switching devices (1, 2) arranged next to one another is located between two longitudinal sides (11, 12) of the two switching devices.

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