EP2146361B1 - Switching device for an electrical switching unit, in particular a medium voltage switching assembly - Google Patents

Description

The invention relates to a switching device for an electrical switching unit, in particular a medium-voltage switchgear.

For example, from the DE 196 32 636 A1 It is known to provide a grounding switch in a cable compartment of a medium-voltage switchgear, with which there can be grounded discharges there. The switching of the earthing switch between its non-grounding and grounding position can be done by an operator. For this purpose, a drive linkage is provided which can be actuated from the outside.

A disadvantage of the known earthing switch is that the drive rod requires a high mechanical complexity and must be created separately for the respective embodiment of the earthing switch.

US 3,459,905 A shows a switchgear with a metal housing, supply switch blades and earthing switch blades. To prevent grounding by means of a grounding switch blade locking means are provided. These locking means prevent grounding by means of the earthing switch blade when the associated food switch blade is closed. The grounding switch blade is moved by means of a tool which is attached to an axis of rotation of the earthing switch blade.

JP 2003257290 A shows a switchgear for performing safe switching operations. The switching operation is performed by means of a motor. A connecting rod is brought to a substantially axial movement. The connecting rod is connected by means of a hinge to a deflection component, which ensures that an actuator rod for a vacuum switch performs an axial movement whose direction is oriented counter to the direction of movement of the connecting rod.

US 4,202,028 discloses a manually operable coupling mechanism. An operating lever is rotatably mounted about an axis and connected at one point with another component, which is also mounted about a further axis of rotation. The further component is connected by means of rods so with an additional component, so that the additional component performs substantially the same movement as the other component.

DE 1106843 B shows a drive arrangement for switching devices in electrical switchgear. A rotational movement of a drive shaft leads by means of two pull / push rods to a rotational movement of a switching shaft. The drive arrangement is used in particular for a deflection of the rotational movement by 90 °.

DE 198 16 592 A1 shows a drive device for three-position switch a switchgear. A linear actuator performs a substantially axial movement in accordance with a Hubantriebsauslenkung. By means of a pivot lever, a push rod is moved substantially axially in accordance with a Schubstangenauslenkung.

JP 8264076 A shows a manually operated grounding device. On a manually driven shaft levers are arranged, which move a switch element of a switch axially. The object of the invention is to provide a switching device which has a simple structure and can be used as flexibly as possible.

The invention solves this problem by a switching device according to claim 1.

The switching device according to the invention comprises the following components: a disc pivotable about a disc axis and swingable from an operator to a second position by an operator, a plate pivotable about a disc axis and coupled to the disc via two rods, that a pivoting movement of the disc leads to a similar pivoting movement of the plate, and a knife pivotable about a knife axis, which is coupled to the plate via two rods such that a pivoting movement of the disc leads to a pivoting movement of the knife.

The switching device according to the invention has an extremely simple mechanical structure and can thus be manufactured and assembled with little effort. Furthermore, the switching device according to the invention has a high reliability due to its simple structure.

Another significant advantage of the switching device according to the invention consists in the fact that at least a part of the components of the switching device identical to different embodiments of the switching devices can be used. In that regard, the switching device according to the invention is modular. Thus, the cost of manufacturing and storage of components are significantly reduced.

It is particularly advantageous if the two rods, which are coupled to the knife, are arranged either approximately parallel to each other, so that the pivoting movement of the disc and the knife are aligned in the same direction, or cross each other, so that the pivoting movement of the disc and of the knife are oriented in opposite directions. By these measures, completely different embodiments of the switching devices can be realized by only the corresponding rods are formed differently.

It is particularly expedient if the disk can be actuated by the operator, in particular by means of a rod, in an approximately vertical direction from top to bottom. This downward pressing of the lever is particularly easy for an operator and without a great deal of effort possible.

In a further advantageous measure, a spring drive is provided in which a spring is tensioned during a transition from one to the other position of the disc, and in which the pivoting movement of the blade is supported by the spring at an opposite transition. Thus, an accelerated transition can be achieved, for example, in the grounding position of a grounding switch.

Other features, applications and advantages of the invention will become apparent from the following description of embodiments of the invention, which are illustrated in the figures of the drawing. All described or illustrated features, alone or in any combination form the subject matter of the invention, regardless of their summary in the claims or their dependency and regardless of their formulation or representation in the description or in the drawing.

FIG. 1 shows a schematic view of a first embodiment of a switching device according to the invention for an electrical switching unit of a medium-voltage switchgear, and

FIG. 2 shows a schematic view of a second embodiment of a switching device according to the invention for an electrical switching unit of a medium-voltage switchgear.

An electrical switchgear in the medium-voltage range is constructed from a plurality of juxtaposed switching units. Each of the switching units has a plurality of modules arranged one above the other, in which, for example, bus bars or circuit breakers or three-position switches or the like are accommodated. The lowest module of a switching unit is often designed as a so-called cable outlet, in which in particular sockets for electrical cables and voltage and / or current transformers are connected and housed.

These sockets or the cables or voltage / current transformers connected there must be earthed. For this purpose, a switching device, a so-called earthing switch is provided, which is manually switchable from the outside from a non-earth to a grounded position and vice versa.

In the FIG. 1 a grounding switch 10 is shown, which is housed in the interior 11 of a cable outlet. All components of the earthing switch 10 described below are connected to a housing 12 of the cable outlet and are thus grounded.

The earthing switch 10 has a disc 15 which is pivotable about a disc axis 16. The disk 15 is preferably circular. The axis 16 is disposed in the interior 11 of the cable outlet and held in a manner not shown on the grounded housing 12 of the cable outlet. A portion of the disc 15 projects beyond the housing 12 of the cable outlet to the outside. In this part of the disc 15, an outwardly projecting rod 17 is connected to the disc 15. With this rod 17, the disc 15 can be pivoted by an operator around the disc axis 16 back and forth.

At a distance from the disk 15, a plate 20 is provided in the interior 11 of the cable outlet, which is pivotable about a plate axis 21. The plate axis 21 and the disc axis 16 are aligned parallel to each other. The plate axis 21 is held in a manner not shown on the grounded housing 12 of the cable outlet.

In the disc 15, two axes 25, 26 are present, which are arranged symmetrically and at the same distance from the disc axis 16. In the plate 20, two axes 27, 28 are also present, which are arranged symmetrically and at the same distance from the plate axis 21. The distance between the two axes 25, 26 of the disc axis 15 and the distance between the two axes 27, 28 of the plate axis 21 is preferably about the same size.

In each case one of the two axes 25, 26 on the disc 15 is pivotally connected via a rod 31, 32 with one of the two axes 27, 28 on the plate 20. The two rods 31, 32 are aligned parallel to each other. Together with an imaginary connecting line between the axes 25, 26 and the axes 27, 28, the rods 31, 32 are part of a parallelogram.

In the plate 20, two further axes 34, 35 are included, which are arranged symmetrically and equidistant from the plate axis 21. The distance of the two axes 34, 35 from the plate axis 21 and the distance of the two axes 27, 28 from the plate axis 21 is preferably different. By an appropriate choice of these different distances can be realized by means of the plate 20, a translation which is not equal to "1". This will be explained below.

At a distance from the plate 20, a knife 40 is provided in the interior 11 of the cable outlet, which is pivotable about a knife axis 41. The knife axis 41, the disk axis 16 and the disk axis 21 are aligned approximately parallel to one another. The knife axis 41 is held in a manner not shown on the grounded housing 12 of the cable outlet.

In the knife 40, two axes 43, 44 are present, which are arranged symmetrically and equidistant from the blade axis 41. The distance between the two axes 43, 44 of the knife axis 41 and the distance between the two axes 34, 35 of the plate axis 21 is preferably about the same size.

In each case one of the two axes 34, 35 on the plate 20 is connected via a rod 47, 48 each having one of the two axes 43, 44 of the blade 40 pivotally connected. The two rods 47, 48 are aligned parallel to each other. Together with an imaginary connecting line between the axles 34, 35 and the axles 43, 44, the rods 47, 48 are part of a parallelogram.

All axes 25, 26, 27, 28, 34, 35, 43, 44 are approximately parallel to each other and approximately parallel to the other axes 16, 21, 41 aligned.

The knife 40 is approximately T-shaped, wherein the knife axis 41 approximately at the intersection of the two legs and the two axes 43, 44 are arranged approximately at the free ends of the shorter leg. The longer leg is free.

In the FIG. 1 is the knife 40 and thus the earthing switch 10 in its non-earthed position (solid line). This means that only the components of the earthing switch 10 are grounded, but that the knife 40 is in electrical contact with no other component, in particular with no current-carrying component. In this non-earthing position, the sockets and voltage and / or current transformers in the cable outlet are not earthed.

With the help of the rod 17, the knife 40 and thus the earthing switch 10 can be transferred to its grounding position. For this purpose, the disk 15 must be pivoted by means of the rod 17 about the disk axis 16, in the present embodiment by about 100 degrees. It is understood that this angular range can also have a different size. Furthermore, the rod 17 must be moved in the present embodiment in approximately vertical direction from bottom to top. Here too It goes without saying that this direction can also be different. The required pivoting of the rod 17 is in the FIG. 1 indicated by an arrow 50.

The pivotal movement of the disc 15 about the disc axis 16 is transmitted from the rods 31, 32 to the plate 20. The plate 20 thus performs a similar pivoting movement about the plate axis 21. The pivotal movement of the plate 20 about the plate axis 21 is transmitted from the rods 47, 48 to the knife 40. The knife 40 thus performs a corresponding pivoting movement about the knife axis 41. The pivoting movement of the knife is in the FIG. 1 indicated by an arrow 51. The pivotal movements of the disc 15, the plate 20 and the blade 40 have the same direction.

Due to the translation realized by the plate 20, the pivoting range of the blade 40 in the present embodiment is smaller than the pivoting range of the disc 15 and is about 90 degrees. It is understood that the explained translation can also lead to a larger pivoting range of the blade 40 in comparison to the disc 15. It is also understood that the aforementioned angular range may have a different size.

In the FIG. 1 a current-carrying component 55 is shown schematically, which may preferably be a busbar. The existing cable outlet sockets and voltage and / or current transformers are connected to this current-carrying component 55. In the grounding position of the blade 41, the current-carrying component 55 is in electrical contact with the blade 41 (dashed line). The im Cable outlet existing sockets and voltage and / or current transformers are grounded with it.

In the FIG. 2 a grounding switch 20 is shown, which is partially identical to the earthing switch 10 of FIG. 1 matches. The matching components are in the FIG. 2 with the same reference numerals as in the FIG. 1 , These are the disc 15, the plate 20, the rods 31, 32 with associated axes 16, 21, 25, 26, 27, 28, 34, 35 and the arrangement and operation of these components in the interior 11 of the cable outlet. For an explanation of these matching components, reference is made to the description of FIG. 1 directed.

Hereinafter, only those components and operations of the earthing switch 20 of the FIG. 2 which differs from the earthing switch 10 of the FIG. 1 differ.

At a distance from the plate 20, a knife 60 is provided in the interior 11 of the cable outlet, which is pivotable about a knife axis 61. The knife axis 61, the disk axis 16 and the disk axis 21 are aligned approximately parallel to one another. The knife axis 61 is held in a manner not shown on the grounded housing 12 of the cable outlet.

In the knife 60, two axes 63, 64 are present, which are arranged symmetrically and at the same distance from the knife axis 61. The distance between the two axes 63, 64 of the knife axis 61 and the distance between the two axes 34, 35 of the plate axis 21 is preferably about the same size.

In each case one of the two axes 34, 35 on the plate 20 is connected via a rod 67, 68 with one of the two axes 64, 63 of the knife 60 pivotally connected. The two rods 67, 68 cross each other.

All axes 25, 26, 27, 28, 34, 35, 63, 64 are approximately parallel to each other and approximately parallel to the other axes 16, 21, 61 aligned.

The knife 60 is elongated, with the knife axis 61 at a free end of the knife 60 and there between the two axes 63, 64 is arranged. The other free end of the knife 60 stands free.

In the FIG. 2 is the knife 60 and thus the earthing switch 20 in its non-earthed position (solid line). This means that only the components of the earthing switch 20 are grounded, but that the knife 60 is in electrical contact with no other component, in particular with no current-carrying component. In this non-earthing position, the sockets and voltage and / or current transformers in the cable outlet are not earthed.

With the help of the rod 17, the knife 60 and thus the earthing switch 20 can be transferred to its grounding position. For this purpose, the disk 15 must be pivoted by means of the rod 17 about the disk axis 16, in the present embodiment by about 100 degrees. Furthermore, the rod 17 must be moved in the present embodiment in approximately vertical direction from bottom to top. The required pivoting of the rod 17 is in the FIG. 2 indicated by the arrow 50.

The pivotal movement of the disc 15 about the disc axis 16 is transmitted from the rods 31, 32 to the plate 20. The plate 20 thus performs a corresponding pivoting movement about the plate axis 21. The pivoting movement of the plate 20 about the plate axis 21 is transmitted from the bars 67, 68 to the knife 60. Due to the intersecting rods 67, 68, the knife 60 performs an opposite pivotal movement about the knife axis 61. The pivotal movement of the knife 60 is in the FIG. 2 indicated by an arrow 53. The pivoting movements of the disc 15 and the plate 20 have, as I said, the opposite direction.

In the FIG. 2 a current-carrying component 57 is shown schematically, which may preferably be a busbar. The existing in the cable outlet sockets and voltage and / or current transformers are connected to this current-carrying component 57. In the grounding position of the blade 61, the current-carrying component 57 is in electrical contact with the blade 61 (dashed line). The existing in the cable outlet sockets and voltage and / or current transformers are thus grounded.

For the transition from its ground to its non-grounding position, the earthing switches 10, 20 described must be pivoted about the axis 16 by means of the rod 17, in the present embodiment in an approximately vertical direction from top to bottom. This operation of the rod 17 is particularly easy to carry out for an operator, since the lever only has to be pressed down.

The pivotal movement from the non-grounding position to the grounding position of the grounding switches 10, 20 described may be assisted by a spring drive. In this case, the transition from the earthy to the non-earth Position, so when operating the rod 17 from top to bottom, tensioned a spring, not shown. Furthermore, the earthing switches 10, 20 are brought in the non-earthed position to an end position which is beyond a dead center. In the operation of the non-earthed position in the grounding position, ie when an operation of the rod 17 from bottom to top, it is now sufficient that the earthing switches 10, 20 are moved by means of the rod 17 only back over the dead center. Thereafter, the further pivoting movement of the knife 40, 60 is supported by the tensioned spring. Thus, this transition from the non-earth position to the ground position is much faster than in the opposite direction.

It is understood that the described earthing switches 10, 20 can also be used quite generally otherwise as a switching device, ie not only in connection with the earthing of live components. It is also understood that this switching device can be used not only in the medium voltage range, but also in other voltage ranges.

Claims (6)

1. Switching device for an electrical switching unit, in particular a medium voltage switching assembly, having a disc (15), swivelable around a disc axis (16), which can be swivelled by an operator back and forth from a first position into a second position, characterised by a plate (20), swivelable around a plate axis (21), which is coupled with the disc (15) via two rods (31, 32) in such a way that a swivelling movement of the disc (15) leads to a similar swivelling movement of the plate (20), as well as by a blade (40; 60), swivelable around a blade axis (41; 61), which is coupled with the plate (20) via two rods (47, 48; 67, 68) in such a way that a swivelling movement of the disc (15) leads to a swivelling movement of the blade (40; 60).
2. Switching device according to claim 1, wherein the two rods (47, 48) which are coupled with the blade (40) are arranged roughly parallel to one another, and wherein the swivelling movement of the disc (15) and of the blade (40) is oriented in the same direction.
3. Switching device according to claim 1, wherein the two rods (67, 68) which are coupled with the blade (60) cross one another, and wherein the swivelling movements of the disc (15) and of the blade (60) are oriented in opposite directions.
4. Switching device according to one of the claims 1 to 3, wherein the disc (15) can be actuated by the operator, in particular with the aid of a rod (17), in a roughly vertical direction, downwards from above.
5. Switching device according to one of the claims 1 to 4, with a spring drive, wherein a spring is tensioned as the disc (15) moves from one position into the other, and wherein the swivelling movement of the blade (40; 60) is supported by the spring in a transition in the opposite direction.
6. Switching device according to one of the claims 1 to 5, said switching device being an earthing switch (10; 20) by means of which a current-carrying component (55; 57) of the switching unit, in particular a busbar, can be brought into electrical contact with the blade (40; 60).

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