EP2024983B1 - Electrical switching arrangement and mounting method - Google Patents

Abstract

The invention relates to an electrical switching arrangement which is arranged in a switching chamber, comprising at least one contact arrangement comprising a moving contact and a fixed contact, with the fixed contact being formed on a fixed contact mount (18) which is arranged at the end (13) of a busbar (10), and, furthermore, with a contact rest mount (20) and a switching arc guide apparatus (30), which is produced from ferromagnetic material, being formed on the fixed contact mount (18). It is proposed that the fixed contact mount (18) be formed with a holding opening (17) and that the switching arc guide apparatus (30) be in the form of an inlay element which can be mounted with a force fit in the holding opening (17) on the fixed contact mount (18).

Description

The invention relates to an electrical switching arrangement, preferably in a multi-pole low-voltage circuit breaker, according to the preamble of claim 1.

From the publication US 5,589,672 or EP0028 740 A an electrical switching device with a fixed and a movable contact is known, in which an arc guide device for dissipation and cooling of the switching arc is present. An arc plate runs approximately in the plane in which the contacts touch. Two baffles forming a so-called slot motor are located parallel to the fixed contact. The contact material is made of highly conductive metal (usually copper); the arc guiding device is made of ferromagnetic material. Because of the different materials, the parts of the contact or contacts and the arc guiding device must be manufactured as separate structures and connected to each other during assembly of the switching device. According to US 5,589,672 The arc guide is screwed from below to the fixed contact. Another option is spot welding or riveting.

In the prior art described above, it is disadvantageous that the installation of an arc guide device on the fixed contact is time-consuming.

The invention is therefore based on the object to provide a switching arrangement with Schaltlichtbogenleitvorrichtung (and an assembly method), in which in particular the Schaltlichtbogenleitvorrichtung is mounted in a simple manner.

The object is achieved by the characterizing features of the independent claim, while the dependent claims advantageous developments of the invention can be found. As an assembly process an ancillary claim is formulated.

The essence of the invention is that the switching arc guiding device is fixed in a clamping manner on the contact support of the fixed contact carrier.

The Schaltlichtbogenleitvorrichtung is designed as an inlay element, which is non-positively mounted during the assembly process on the contact support carrier in a receiving opening.

The Schaltlichtbogenleitvorrichtung can thus be secured without welding, riveting or screwing on the busbar of the fixed contact carrier.

The Schaltlichtbogenleitvorrichtung consists of an elongated elongated base member on which - in the mounted state on the fixed contact carrier - at least one guide plate on a connection surface far front, on its connection surface near the rear part Ableithorn, and in the middle a mounting window is formed.

At the contact support support a receiving tongue is arranged, which is directed by a connection surface on the fixed contact carrier arranged transverse strut, starting in the direction of the connection surface. Then formed on the Schaltlichtbogenleitvorrichtung two, top and bottom edges of a mounting window forming abutment surfaces, of which the upper contact surface - during mounting process - above the receiving tongue and the lower contact surface - come to rest below the receiving tongue during the assembly process - and wherein the distance between the contact surfaces, which are approximately parallel to each other, is smaller than the thickness of the receiving tongue. The Schaltlichtbogenleitvorrichtung is slidably pushed onto the receiving tongue on the contact support carrier, after which the Schaltlichtbogenleitvorrichtung is clamped on the contact support carrier.

Furthermore, a reference surface is defined, to which - to explain the geometric Details - other dimensions are related. The reference surface consists of the contact surface of the upper contact surface with the surface of the receiving tongue.

In addition, a direction indication above and below the reference surface is defined such that elements of the bus bar and the arc switching device that come to rest in the quenching chamber of the switching device are referred to as above the reference surface (or top).
A further preferred embodiment of the invention is that the switching arc guide device can be fastened in the manner of a 3-point locking on the busbar.

For this purpose, it is provided that the surface of the transverse strut is located by a strut distance below the reference surface and that on at least one baffle, a detent is arranged, which is in the pushed on the receiving tongue state of Schaltlichtbogenleitvorrichtung to a latching nickle below the reference surface, wherein the Latching distance is greater than the longwall distance, so that the at least one locking lug comes to lie below the reference surface. The surface of the crossbar and the surface of the receiving tongue should be approximately parallel.

At the front of the Schaltlichtbogenleitvorrichtung at least one locking lug is arranged, which is in the position of a deferred to the receiving tongue Schaltlichtbogenleitvorrichtung a locking lug spacing below the reference surface, wherein the detent lug spacing is greater than the longwall distance. After being pushed onto the receiving tongue, the at least one latching lug comes to lie below the edge of the transverse strut directed towards the receiving opening. By making an elastic deformation, the deferred Schaltlichtbogenleitvorrichtung can raise over the transverse edge of the strip and advance by applying a force with parallel to the reference surface force vector on the transverse edge of the scraper. The at least one locking lug comes to lie on the crossbar.

For reasons of symmetry, two detents may be provided, one of which at the leading edge (viewed in the direction of the cross member) on the guide plates are arranged.

Preferably, the contact arrangement may also be formed on a double-interrupting switching arrangement. That is, it is an embodiment in which the arrangement according to the invention is present in duplicate at a switch pole.

When mounting a Schaltlichtbogenleitvorrichtung invention the Schaltlichtbogenleitvorrichtung is pushed onto the receiving tongue. The exact arrangement of the mounting window on the receiving tongue is sufficient for permanent fixation. Here it comes to the 2-point clamping on the receiving tongue. This embodiment is sufficient for many applications. However, in order to make higher demands on the switching contact, it is recommended to use the preferably embodiment of the invention, in which ultimately a 3-point locking of the switching arc guide device comes about.

There are then applied two more assembly steps.

2. Assembly step: application of a force exerted below the reference surface for elastically deforming the front part of the switching arc guiding device by means of which the front part is moved towards the reference surface, so that the at least one latching lug is raised at least into the plane of the surface of the transverse strut.

3rd assembly step: Applying a lying in the plane of the reference surface, in the direction of the cross strut force applied, so that the at least one latching lug is pushed onto the surface of the transverse strut and comes to rest there.

Fig. 1:

eine perspektivische Darstellung der Stromschiene,

Fig. 2A:

eine perspektivische Darstellung der Schaltlichtbogenleitvorrichtung,

Fig. 2B:

die Schaltlichtbogenleitvorrichtung im Schnitt,

Fig. 3 u. 4:

Montagefolge (M1 bis M7) der Schaltlichtbogenleitvorrichtung auf der Stromschiene,

Fig. 5:

eine perspektivische Darstellung der Stromschiene mit montierter Schaltlichtbogenleitvorrichtung und

Fig. 6:

eine Einbausituation von Stromschiene mit Schaltlichtbogenleitvorrichtung in einer Schaltkammer.

Further details and advantages of the invention will become apparent from the following, explained with reference to figures embodiment. Show it

Fig. 1:

a perspective view of the busbar,

Fig. 2A:

a perspective view of the Schaltlichtbogenleitvorrichtung,

Fig. 2B:

the switching arc guiding device in section,

Fig. 3 u. 4:

Assembly sequence (M1 to M7) of the switching arc guide device on the busbar,

Fig. 5:

a perspective view of the busbar with mounted Schaltlichtbogenleitvorrichtung and

Fig. 6:

an installation situation of busbar with Schaltlichtbogenleitvorrichtung in a switching chamber.

As in Fig. 1 and 2 shown, the fixed contact at the end 13 of a - preferably formed of copper - busbar 10 is arranged, wherein the fixed contact carrier has a receiving opening 17. The receiving opening 17 is closed by a transverse leg 14 present in relation to the connecting surface of the busbar. The connection surface 11 is - as shown in the figure - designed as a fastening strap with a mounting hole.

On both sides of the receiving opening 17 are two side legs 12, resulting in a split current path from the pad of the bus bar towards the contact pad 22. The contact pad 22 is seated on a contact tongue 20, which projects inwardly on the transverse leg 14 in the vorbezeichnet recording opening 17. The divided in the side legs currents reunite in the contact tongue 20. The busbar is angled approximately Z-shaped so that pad 11 1 and the fixed contact carrier 18 including contact tongue 20 are approximately parallel.

The dimensions of the side legs 12, the transverse leg 14 and the contact tongue 20 are adapted to the current carrying capacity required in the switching arrangement. However, the arrangement according to the invention is independent of the present or required geometric dimensions. According to the drawing, the widths (and equally the conductor cross-sections) of the two side legs, the transverse leg and the contact tongue are approximately equal.

The width of the receiving opening 17 is greater than the width of the contact tongue 20, since - As shown in more detail - the baffles 33 of the arc guiding device also reach through the receiving opening. Therefore, the width of the receiving opening is dimensioned so that there is space for twice the material thickness of the baffles (in addition to the width of the base member 32).

The contact tongue 20 is out of the plane in which the contact carrier 18, the two side legs and the transverse strut 14 are (in the direction of the connection surface) upwardly bent. Thus, the connection surface 11 of the busbar, the transverse strut 14 and the contact tongue 20 are in three approximately parallel planes, wherein the contact tongue 20 between the plane of the connection surface 11 and the surface of the crossbar 14 is located. In the (later) installation position of the fixed contact in the switching chamber, the contact tongue 20 (together with the arranged on the contact tongue arc guiding device) in the arc extinguishing chamber of the switching arrangement. In addition, the directed to the quenching chamber position of the items is referred to as upper layers or with 'top'.

The receiving tongue 24 on the contact support support 20 is - starting from the cross strut 14 of the fixed contact carrier - directed in the direction of the connection surface. The bending back of the contact tongue 20 in the direction of the contact surface of the busbar means for the current flow that an electrodynamic opening force is formed at the location of the contact between solid contact (contact pad 22) and the - not shown - moving contact, that of the opposite course of the electric current in the side legs 12 and the contact tongue 20. In the case of an increased fault current, a force is created to support the contact opening. The movable contact is coupled in a manner not shown, usually with a switch lock.

With the opening of the contacts of the switching arc, the shortest possible time of the contact pad 22 - on the Ableithorn 40 - weggeführt and deleted. For this purpose, the arc guiding device 30 is used, which is formed from ferromagnetic material. The arc guide 30 causes the magnetic flux density in the contact area to be enhanced because the magnetic field lines are converged by the arc guide. This leads to an acceleration of the electrodynamic repulsive forces between fixed contact and moving contact caused opening swinging motion of the moving contact due to an excessive fault current.

In the Fig. 2A shown arc guide 30 is made of a flat sheet of steel. The special shape is created by punching and bending.

The basic element of the arc guide device 30 is an elongate elongated body 32, consisting of a front part carrying the guide plates 33 and a rear part comprising a discharge horn 40. At the front of the two baffles 33 are arranged laterally - approximately at right angles - bent. The width of the arc guide device is slightly smaller than the width of the receiving opening 17th

Symmetrically to the longitudinal axis in the arc guiding device, an opening or a mounting window is formed, in which - during the assembly process - the receiving tongue 24 enters. Upper and lower edge of the mounting window form two - in the further considered closer - contact surfaces 35, 36. The window height corresponds to the distance of the contact surfaces 35, 36 which are approximately parallel to each other, the upper edge of the window is formed as a material web 38.

The upper contact surface 35 comes to lie on the surface 25 of the receiving tongue 24 during the assembly process. The second contact surface 36 comes to lie below the receiving tongue 24 during the assembly process. In the following, therefore, the contact surface of the upper abutment surface 35 with the surface 25 of the receiving tongue 24 as a reference surface BZ (see Fig. 2B ) Are defined. On the reference surface BZ - to explain the geometric details - other dimensions related.
The substantially only of a Ableithorn 40 rear part of the body 32 is against the reference surface BZ (and thus opposite the material web 38 of the upper edge of the window) by an angle W, which may be in the range of 25 ° to 30 °, upwards (in the direction Extinguishing chamber) angled.

The front part of the Schaltlichtbogenleitvorrichtung 30 carries - as already mentioned - the two baffles 33, which extend substantially at right angles to the reference surface BZ - also upwards. The foot lines of the baffles (bends) on Front part lie - approximately in continuation of the line formed by Ableithorn - below the reference surface BZ. At the front edge of the baffles 33 (seen in the direction of the cross member) is ever a latch 34. As out Fig. 2B can be seen, the locking lugs 34 are also disposed below the reference surface BZ.

As shown, the arc guide has three essential elements: first, the arc-Ableithorn 40, second, the mounting window and third, the two U-shaped baffles 33. The baffles 33 laterally limit the contact space. The discharging horn 40 constitutes (in the assembly position) an extension of the contact tongue 20 for the purpose of guiding the foot of the burning switching arc away from the contact support 22 and in the direction of a quenching plate stack arranged in the quenching chamber.

The mounting window is located approximately in the middle of the longitudinal extent of the body, where the body is slightly bent, or designed angled (see Fig. 2B ).

As in the following in the in the Figures 3 and 4 shown assembly sequence (M1 to M7) can be seen, the mounting window of the arc guiding device with the direction of movement of the contact surface of the busbar towards the crossbar 14 of the busbar 10 is slid over the receiving tongue 24 slidably.

For frictional attachment of the distance between the contact surfaces 35, 36 (the window height) is chosen smaller than the thickness of the receiving tongue 24. The contact surfaces form the jaws of a pair of pliers, which - elastically yielding - widen during assembly. The corresponding elastic deformation results in a 2-point clamping on the receiving tongue.

In the pushed-layer position of the arc guide device 30 on the contact support support 20 'dives' the front part with the formed on the baffles 34 locking lugs 36 in the receiving opening 17 a. When a pressure FV is applied from below, the front part can be elastically deformed with respect to the rear part clamped onto the receiving tongue 24 on the contact support carrier 20, whereby the latching lugs 36 are raised to such an extent that they are directed onto the receiving opening Edge 16 of the transverse leg 14 rest.

For mounting the Schaltlichtbogenleitvorrichtung be Figures 3 and 4 used. They show the assembly sequence of the Schaltlichtbogenleitvorrichtung on the power rail, with the individual mounting steps M1 to M7. The subfigures M1 to M7 are each longitudinal sections of the arrangement.

In the first phase (M1) of the assembly, the switching arc guiding device is introduced from above into the receiving opening.

In the further phases (M2 to M5), the switching arc guiding device is pushed onto the receiving tongue. It comes to 2-point clamping on the receiving tongue.

In the subsequent assembly step (M6) is applied from below the reference surface BZ a force FV for elastic deformation of the front part of the Schaltlichtbogenleitvorrichtung, by means of the front part is moved to the reference surface BZ, so that the at least one latching lug (or both) at least in the plane of Surface 15 of the crossbar 14 is raised.

In the last assembly step, a lying in the plane of the reference surface BZ, applied in the direction of the cross member 14 force FM is applied so that the (at least one) detent is pushed onto the surface 15 of the cross member 14 and comes to rest there. After this, a 3-point locking of the switching arc guiding device is achieved.

In the FIG. 5 there is a perspective view of the busbar with mounted Schaltlichtbogenleitvorrichtung.

With FIG. 6 a situation during the mounting of busbar with switching arc guiding device is shown in a switching chamber. The Schaltlichtbogenleitvorrichtung is located at a distance in front of the switching chamber, in which the Schaltlichtbogenleitvorrichtung is to be inserted, so that the Schaltlichtbogenleitvorrichtung completely closes the inlet opening. In the switching chamber is one for such switching arrangements usual Löschblechstapel arranged.

It can be seen that the baffles enter the switching chamber. Preferably, the baffles can be spread apart, for example, so that when it is inserted into the switching chamber latching takes place. For this purpose, the two baffles 33 should be arranged slightly further than at right angles bent at the front of the Schaltlichtbogenleitvorrichtung. To support the latching can be arranged on one or both baffles a locking lug or the like, whereby the latching is vornehmbar non-positively.

LIST OF REFERENCE NUMBERS

10

conductor rail

11

Connection surface (tab)

12

side leg

13

Contact carrier end of the busbar

14

crossmember

15

Top cross strut

16

Crossmember edge

17

receiving opening

18

contact support

20

Contact support beams

22

contact support

24

support tongue

25

Top of the tongue

26

Underside retainer tongue

30

Schaltlichtbogenleitvorrichtung

32

Ground or ground body

33

running plates

34

locking lug

35

upper contact surface

36

lower contact surface

38

material web

40

Ableithorn

60

Switching chamber including extinguishing device

BZ

reference plane

L1; L2

Lengths of contact surfaces

D1

Distance between contact surfaces

D2

Distance lower edge of detent to reference plane

D

Thickness of the tongue

H

Distance top crossbar to top of seat tongue

W

Angle (W = 25 to 30 °)

Claims (8)

1. Electric switching arrangement which can be arranged in an arcing chamber,

   - comprising at least one contact arrangement consisting of a moving contact and a fixed contact,

   - the fixed contact being connected to a busbar (10) having a connection face (11), and the fixed contact, remote from the connection face, being formed on a fixed contact carrier (18),

   - and a contact facing carrier (20) and a switch arc guiding device (30) made of ferromagnetic material also being formed on the fixed contact carrier (18),
   characterised in that

   - the switch arc guiding device (30) is clamped to the contact facing carrier (20) of the fixed contact carrier (18).
2. Switching arrangement according to claim 1, characterised in that the switch arc guiding device (30) consists of an elongate base element (32) on which the following are formed: on a front portion remote from the connection face at least one baffle plate (33), on the rear portion close to the connection face a discharge horn (40), and a mounting window (35, 36).
3. Switching arrangement according to either claim 1 or claim 2, characterised in that

   - a receiving tab (24) is arranged on the contact facing carrier (20) and projects towards the connection face (11) from a cross strut (14) which is arranged on the fixed contact carrier (18) so as to be remote from the connection face,

   - and in that an upper edge and a lower edge of the mounting window are each formed as an abutment face (35, 36), the upper abutment face (35) abutting the top of the receiving tab (24) and the lower abutment face (36) abutting the bottom of the receiving tab (24), and the distance between the abutment faces (35, 36) being less than the thickness of the receiving tab (24).
4. Switching arrangement according to claim 3, characterised in that

   - starting from a reference plane (BZ) defined by the area of contact between a surface (25) of the receiving tab (24) and the upper abutment face (35), the surface (15) of the cross strut (14) is located a strut distance (H) below the reference plane (BZ),

   - and in that a catch (34) is arranged on at least one baffle plate (33) and is located a catch distance (D2) below the reference plane (BZ), the catch distance (D2) being greater than the strut distance (H), such that the at least one catch (34) is located below the reference plane (BZ).
5. Switching arrangement according to claim 4, characterised in that a catch (34) is arranged on each baffle plate (33).
6. Switching arrangement according to the preceding claim, characterised in that a quenching plate stack is arranged in the arcing chamber (60).
7. Switching arrangement according to any of the preceding claims, characterised in that the contact arrangement is formed on a double-break switching arrangement.
8. Method for mounting a switch arc guiding device (30) defined in the preceding claims, the method comprising the following mounting steps:

   - pushing the switch arc guiding device (30) onto the receiving tab (24),

   - applying a force (FV) exerted from below the reference plane (BZ) to resiliently deform the front portion of the switch arc guiding device (30), by means of which force the front portion is moved towards the reference plane (BZ) such that the at least one catch (34) is lifted into the plane of the surface (15) of the cross strut (14), and

   - applying a force (FM) located in the reference plane and exerted towards the cross strut (14), such that the at least one catch (34) comes to rest on the surface (15) of the cross strut (14).

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