EP3084794B1 - Schaltgeraet - Google Patents

Description

In mechanical switching devices, an arc occurs during each shutdown process. This is unavoidable due to the physical conditions described in Induktionsgesetzt. When switching off very high currents, as occur for example in case of short circuits, the resulting arc is a serious threat to the relevant switching device, but also the circuit environment. On the one hand, the arc can destroy the switching device itself, on the other hand, this continues to form a conductive electrical connection, which is why in the circuit in question continues to flow, and thus continue to pose a significant threat to people and equipment. In particular, when switching DC currents there is an additional risk of electric arcs, as they hardly go out without further intervention in the absence of a zero crossing.

From the DE 1 590 167 a switch is known which has two parallel current paths.

The object of the invention is therefore to provide a switching device of the type mentioned, with which the mentioned disadvantages can be avoided, with which high DC currents can be safely switched off, and which has a small size.

This is achieved by the features of claim 1 according to the invention.

As a result, high DC currents can be switched off safely. As a result, an arc occurring when switching off high DC currents can be rapidly extinguished, and thus the current flow through the switching device are interrupted. This eliminates the need for an additional or separate arc extinguishing chamber, whereby a - compared to switching devices with the same switching capacity - smaller size can be achieved with additional security of Abschaltfähigkeit. As a result, the safety in electrical installations, in particular in electrical DC systems, can be increased, and improved protection of people and

Plants against damaging effects of electric current can be achieved. This can further also the total burden of
be reduced in a short circuit, as there is a reduction in the maximum flowing short-circuit current.

The subclaims relate to further advantageous embodiments of the invention.

It is hereby expressly referred to the wording of the claims, whereby the claims at this point are incorporated by reference into the description and are considered to be reproduced verbatim.

• Fig. 1 eine schematische Darstellung einer ersten bevorzugten Ausführungsform eines gegenständlichen Schaltgeräts in einem ersten Zustand;
• Fig. 2 eine schematische Darstellung des Schaltgeräts gemäß Fig. 1 in einem zweiten Zustand;
• Fig. 3 eine schematische Darstellung des Schaltgeräts gemäß Fig. 1 in einem dritten Zustand;
• Fig. 4 eine schematische Darstellung einer zweiten bevorzugten Ausführungsform eines gegenständlichen Schaltgeräts in einem ersten Zustand;
• Fig. 5 eine schematische Darstellung des Schaltgeräts gemäß Fig. 4 in einem zweiten Zustand; und
• Fig. 6 eine schematische Darstellung des Schaltgeräts gemäß Fig. 5 in einem dritten Zustand.

The invention will be described in more detail with reference to the accompanying drawings, in which only preferred embodiments are shown by way of example. Showing:

• Fig. 1 a schematic representation of a first preferred embodiment of a subject switching device in a first state;
• Fig. 2 a schematic representation of the switching device according to Fig. 1 in a second state;
• Fig. 3 a schematic representation of the switching device according to Fig. 1 in a third state;
• Fig. 4 a schematic representation of a second preferred embodiment of an objective switching device in a first state;
• Fig. 5 a schematic representation of the switching device according to Fig. 4 in a second state; and
• Fig. 6 a schematic representation of the switching device according to Fig. 5 in a third state.

The Fig. 1 to 6 each show schematic representations of preferred embodiments of a switching device 1, wherein the switching device 1 has first switching contacts 2, which are in a closed state part of a first current path 3 from a first terminal 4 of the switching device 1 to a second terminal 5 of the switching device 1, wherein the switching device 1 has a switching mechanism 6, which is designed, after actuation by a trigger 7, in a first step to separate the first switching contacts 2, wherein circuitry a second current path 8 is arranged parallel to the first switching contacts 2, wherein the second current path 8 is a predetermined Has a plurality of serially arranged second switch contacts 9, and wherein the switching mechanism 6 is formed in a - the first step -nachfolgenden second step, the second switching contacts 9 each separate from each other.

As a result, high DC currents can be switched off safely. As a result, an arc occurring when switching off high direct currents can be rapidly extinguished, and thus the current flow through the switching device 1 are interrupted. As a result, can be dispensed with an additional or separate arc extinguishing chamber, whereby a - compared to conventional switching devices with the same switching capacity - smaller size can be achieved with additional security of Abschaltfähigkeit. As a result, the safety in electrical installations, in particular in direct current electrical installations, can be increased, and improved protection of people and installations against damaging effects of the electric current can be achieved. As a result, the total load of the electrical systems can also be reduced in the event of a short circuit, since a reduction in the maximum flowing short-circuit current takes place.

The switching device 1 can be any type of electrical switching device 1, therefore a device for switching electrical currents, trade. It is preferably provided that the switching device 1 is a DC switching device, therefore, a switching device 1, which is provided in particular for switching DC, especially for switching the prevailing for photovoltaic systems voltages of 600 V DC.

The Fig. 1 to 6 show in each case schematic representations, wherein only the respective first and second switching contacts 2, 9 are shown in more detail.

The switching device 1 preferably has a handle, not shown, for opening and closing the first and second switching contacts 2, 9. Preferably, and as in the Fig. 1 to 6 illustrated, it is provided that the switching device 1 is designed as a protective switching device, therefore, as a switching device 1, which automatically causes the occurrence of certain electrical states opening the switching contacts 2, 9, and accordingly has a so-called. Triggers 7. Preferably, the trigger 7 is designed as a short-circuit release, with an overcurrent release can be provided. Such triggers 7 are well known in the field. the trigger is in the Fig. 1 to 6 only schematically shown as a common unit with the rear derailleur 6, which of course structurally separate conversions can also be provided.

Furthermore, the switching device 1 has an insulating material housing, on which the Terminals 4, 5 are arranged.

The switching device 1 has, in a manner known per se, first switching contacts 2, which in a closed state are part of a first current path 3 from the first terminal 4 of the switching device 1 to the second terminal 5 of the switching device 1. Closed state means that the contact elements of the first switching contacts 2 are in contact, therefore form a conductive connection, which is formed by contact of two solids.

The first switching contacts 2 are in the subject Fig. 1 to 6 each formed as a pairing of a movable contact element and a housing-fixed contact element. It can also be provided to connect two housing-fixed contact elements by a movable switching bridge, and to form such a so-called. Double interruption.

The switching device 1 has a mechanical switching mechanism 6, which is preferably designed as a switch lock. At least one contact element of the first switching contacts 2 is connected to the rear derailleur 6 or controlled by the switching mechanism 6 or actuated. It is provided that the switching mechanism 6 is formed, after actuation by the trigger 7, to separate the first switching contacts 2 in a first step. It is of course provided that the first switching contacts 2 were previously closed. The Fig. 1 and FIG. 4 show an objective switching device in a first state of closed first as well as second switching contacts 2, 9. It can also be provided that the switching mechanism 6 is designed to act in such a way even when switched off manually.

It is envisaged that, in terms of circuitry, a second current path 8 is arranged parallel to the first switching contacts 2. The second current path 8 preferably branches off from the first current path 3 only in the region of the first switching contacts 2. In the second current path 8, a predeterminable plurality of serially arranged second switching contacts 9 are arranged.

The second switching contacts 9 comprise at least one housing-fixed first fixed contact 14, as well as a plurality of movably arranged in the switching device 1 contact plates 12. In the first or switched state of the switching device 1, the second switching contacts 9 are in contact and form a conductive connection within the In this case, a first contact plate 12, 13 of the plurality of contact plates 12 is applied to the first fixed contact 14 of the second switching contacts 9. It is provided that the second current path 8 has a higher resistance, in particular a at least 10 times, preferably at least 100 times higher resistance, than the circuitry parallel to this running portion of the first current path 3, comprising the first switching contacts 2. This can be achieved that in normal operation of the switching device 1, only a very low current flow over the second current path 8 occurs, and only a small leakage line occurs in this area.

It is preferably provided that the contact plates 12 have a ferromagnetic material, in particular steel. Due to the higher specific resistance of ferromagnetic materials compared to copper, a higher resistance of the second switching path can be achieved easily. The preferred embodiment of the contact plates 12 comprising steel also has the advantage of high robustness and thermal resistance.

The switching mechanism 6 is further configured to separate the plurality of second switching contacts 9 from one another in a second step, the first step, following. The Fig. 1 and 4 each show a switching device in the first state closed first two second switching contacts 2, 9. After actuation of the switching mechanism 6 by the trigger 7 only the first switching contacts 2 are separated. Since there is still a conductive connection via the second current 8, in this state, the entire current flow shifts to the second current path 8. Due to the considerably higher resistance of the second current path 8 with respect to the first current path 3, the current flowing through the switching device 1 Electricity can be reduced. The second state in question is in the fog. 2 and 5, respectively. In the now following second step, the switching mechanism 6 separates the second switching contacts 9 or causes this separation of the second switching contacts 9. Since there is no further line-connected connection within the switching device 1, arcs occur between adjacent contact plates 12 Switchgear, in which the achievement of a high arc voltage requires a longer time, since the arc has to migrate from the switch contacts in the usual in such conventional switchgear blur stack and there is divided into partial arcs are, in representational switching device 1, the contact plates 12 substantially opened simultaneously, which quickly when switching off the switching device 1 or contact opening high arc voltage is reached, which counteracts a driving source voltage and thus limits the current through the switching device 1 faster than at conventional switching devices. The arc voltage is thereby the sum of the voltages of the Partial arcs. In addition, the individual arcs are effectively cooled by the plurality of contact plates 12.

By selecting the specific number of contact plates 12 used, the relevant switching device 1 can be adapted in the design to the intended threshold voltage.

The contact plates 12 can be made different in terms of their concrete training, such as a circular or rectangular plate. It can be provided that these are designed as composite bodies comprising a plurality of materials. In addition, it can be provided that the contact plates 12 have projecting contact area, which are provided to contact the respectively adjacent contact plate 12.

It is preferably provided that the switching mechanism 6 has a first actuating element 10 for the at least indirect separation of the first switching contacts 2, and that the switching mechanism 6 has a second actuating element 11 for at least indirect separation of the second switching contacts 9. The first as second actuating element 10, 11 are in the Fig. 1 to 6 only symbolized by lines. The specific design of the relevant rear derailleur 6 is strongly dependent on the other requirements for the relevant switching device 1 and is not further explained representational.

The Fig. 1 to 3 show a first preferred embodiment of a subject switching device 1, wherein the contact plates 12 are each mounted rotatably movable. The individual contact plates 12 are arranged rotatably mounted in a central region in the switching device 1. The contact plates 12 are connected to each other by means of an actuating rod 20, which actuating rod 20 is at least indirectly in operative connection with the rear derailleur 6. The actuating rod 20 is preferably spaced apart from the central region at the individual contact plates 12 rotatably mounted in order to achieve a good leverage.

An outer, the first fixed contact 14 remote contact plate 15, 12 cooperates with a second fixed contact 19 of the second switching contacts 9 by these in the in the Fig. 1 and 2 shown tilted position of the contact plates 12 makes the conductive contact to the second terminal 5.

In a first position of the actuating rod 20, the contact plates 12 are each together, and form an electrically conductive connection, which forms part of the second current path 8, as shown in the Fig. 1 and 2 is shown. In a second position of the actuating rod 20, the contact plates 12 are each arranged substantially uniformly spaced from each other, as in Fig. 3 is shown.

The 4 to 6 show a second preferred embodiment of an objective switching device 1, wherein the contact plates 12 are mounted to be longitudinally displaceable movable. The term longitudinally displaceable means in particular that the displacement takes place along a straight line, therefore as a translatory movement. It is preferably provided that the displacement direction is arranged substantially normal to a flat extension of the contact plates 12.

The outer, the first fixed contact 14 remote from the contact plate 15, 12 is preferably connected by means of a flexible conductor 16 with the first current path 3 circuitry. The Fig. 1 and 2 each show the second switching contacts 9 in the closed position.

According to the illustrated preferred embodiment, it is provided that at least one spring 17 is arranged between the individual contact plates 12, which are under bias in the closed position of the second switching contacts 9. The springs 17 are preferably formed as helical springs, through whose central passage opening a guide rod 22 is guided, which also passes through the contact plates 12.

The contact plates 12 are preferably in accordance with a locking device 18 of the derailleur 6 in the closed position Fig. 1 to 2 held, against the bias of the springs 17. In this case, the switching mechanism 6 is formed such that in the second step, the locking device 18 is actuated or unlocked, resulting in the sudden opening of the second switching contacts 9.

Not shown is another preferred device of the relevant switching device 1, which brings the contact plates 12 together again in the, in particular manual, closing the switch contacts 2, 9 of the switching device 1, thereby applying the bias of the springs 17, and the locking device 18 in the corresponding position brings.

Claims (14)

1. Switchgear (1), in particular a direct current switchgear, wherein the switchgear (1) comprises first switch contacts (2) which, in a closed state, are part of a first current path (3) from a first connecting terminal (4) of the switchgear (1) to a second connecting terminal (5) of the switchgear (1), wherein a second current path (8) is arranged parallel, in terms of circuitry, to the first switch contacts (2), wherein the second current path (8) comprises a predeterminable plurality of second switch contacts (9) arranged in series and comprising at least one first fixed contact (14) fixed to the housing, characterised in that the second switch contacts (9) comprise a plurality of contact plates (12) moveably arranged in the switchgear (1) which abut each other in a switched state of the switchgear (1) and form a conductive connection within the second current path (8), wherein a first contact plate (12, 13) of the plurality of contact plates (12) abuts the first fixed contact (14) of the second switch contacts (9), that the switchgear (1) comprises a switch mechanism (6) configured to disconnect the first switch contacts (2) in a first step after actuation by an actuator (7), and that the switch mechanism (6) is configured to disconnect the second switch contacts (9) from each other in a subsequent second step following the first step, by forming arcs between adjacent contact plates (12).
2. Switchgear (1) according to claim 1, characterised in that the switch mechanism (6) comprises a first actuating element (10), for at least indirectly disconnecting the first switch contacts (2), and that the switch mechanism (6) comprises a second actuating element (11), for at least indirectly disconnecting the second switch contacts (9).
3. Switchgear (1) according to claim 1 or 2, characterised in that the second current path (8) has a higher resistance, in particular a resistance 10 times higher, preferably a resistance at least 100 times higher, than the section of the first current path (3) extending parallel, in terms of circuitry, to the second current path and comprising the first switch contacts (2).
4. Switchgear (1) according to claim 3, characterised in that the contact plates (12) comprise a ferromagnetic material, in particular steel.
5. Switchgear (1) according to claim 3 or 4, characterised in that the contact plates (12) are mounted so as to be movable in a longitudinal direction.
6. Switchgear (1) according to any of claims 3 to 5, characterised in that an outer contact plate (15, 12) of the plurality of contact plates (12) that is facing away from the first fixed contact (14) is connected in terms of circuitry to the first current path (3) by means of a flexible conductor (16).
7. Switchgear (1) according to any of claims 3 to 6, characterised in that a spring (17) is arranged between the single contact plates (12) which is preloaded in a closed position of the second switch contacts (9).
8. Switchgear (1) according to claim 7, characterised in that the switch mechanism (6) comprises a locking device (18) which keeps the second switch contacts (9) in contact against the spring force of the preloaded spring (17) and which can be unlocked in a predetermined manner.
9. Switchgear (1) according to claim 3 or 4, characterised in that the contact plates (12) are mounted so as to be rotationally moveable.
10. Switchgear (1) according to claim 9, characterised in that an outer contact plate (15, 12) facing away from the first fixed contact (14) interacts with a second fixed contact (19) of the second switch contacts (9).
11. Switchgear (1) according to claim 9 or 10, characterised in that the contact plates (12) are connected to each other by means of an actuation rod (20), and that the actuation rod (20) is at least indirectly operatively connected to the switch mechanism (6).
12. Switchgear (1) according to any of claims 9 to 11, characterised in that the contact plates (12) abut each other in a first position of the actuation rod (20) and form an electrically conducting connection, and that the contact plates (12) are arranged substantially evenly spaced apart from each other in a second position of the actuation rod (20).
13. Switchgear (1) according to any of claims 1 to 12, characterised in that the actuator (7) is a short circuit actuator.
14. Switchgear (1) according to any of claims 1 to 13, characterised in that the contact plates (12) are opened substantially simultaneously.

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