Electrical switching device

Abstract

The invention relates to an electrical switching device (1).The switching device (1) comprises a housing (3), an electrical main conductor (5) fixedly arranged in the housing (3), at least one electrical contact element (7, 8) fixedly arranged in the housing (3), for each contact element (7, 8) a switching element (9, 10) arranged in the housing (3) which is movable between a first switching position in which it rests against the contact element (7, 8) and a second switching position in which it is separated from the contact element (7, 8), a movably mounted guide element (12), for each switching element (9, 10) a kinematic chain (13) by which the switching element (9, 10) is coupled to the guide element (12) so that movements of the guide element (12) cause movements of the switching element (9, 10), a switching drive (14) for moving the guide element (12) and for each switching element (9, 10) a Connecting assembly (15) which electrically connects the switching element (9, 10) to the main conductor (5).

Description

[0001] The invention relates to an electrical switching device.

[0002] In particular, the invention relates to an electrical switching device for a gas-insulated switchgear. In gas-insulated switchgear, a switching device typically comprises a housing that is gas-tight and filled with an insulating gas during operation of the switching device.

[0003] Furthermore, the invention particularly relates to a switching device having multiple isolating gaps and whose movable switching elements are driven by a single switching drive. In such a switching device, the movable switching elements can, for example, be permanently connected to one another and moved by means of a multi-position drive. A disadvantage here is that moving one switching element causes the other switching elements to move. Since such a movement must not impair the function of the switching device, it requires a relatively large installation space. In particular, the requirement to enable a switching state in which all isolating gaps are closed requires a very large installation space when all switching elements are moved simultaneously in order to move the switching elements while taking all interdependencies into account.

[0004] EP 2 771 896 B1 discloses an electrical switching device comprising a common subsection of a power grid, a pair of subdivision sections of the grid, wherein the subdivision sections may be busbars, and a circuit arranged at a contact point of the common subsection and the subdivision sections. The circuit comprises a first fixed contact piece connected to the common subsection and two fixed contact pieces connected to the respective subdivision sections and each having a connection area provided with a recess. The two fixed contact pieces are opposite one another in the circuit, and the recesses face each other.The circuit further comprises a movable contact piece electrically connected to the first fixed contact piece and arranged between the connecting regions, and a control device that displaces the movable contact piece along a line connecting the connecting regions. Only one movable contact piece is provided, and this has a length that is greater than a distance between the connecting regions, but less than the distance plus a depth of one of the recesses.

[0005] The invention is based on the object of providing an improved electrical switching device which, in particular, enables a space-saving realization of several isolating sections, wherein the movable switching elements can be driven by a common switching drive.

[0006] The object is achieved according to the invention by an electrical switching device having the features of claim 1.

[0007] Advantageous embodiments of the invention are the subject of the subclaims.

[0008] An electrical switching device according to the invention comprises - a housing, - a main electrical conductor fixed in the housing, - at least one electrical contact element fixedly arranged in the housing, - for each contact element, a switching element arranged in the housing, which is movable between a first switching position in which it rests against the electrical contact element and is electrically connected to the electrical contact element, and a second switching position in which it is separated from the electrical contact element, - a movably mounted guide element, - for each switching element, a kinematic chain by which the switching element is coupled to the guide element, so that movements of the guide element cause movements of the switching element, - a switching drive which is designed to move the guide element, and - for each switching element, a connecting assembly which electrically connects the switching element to the main conductor and for this purpose is connected to the switching element by a first rotary joint and to the main conductor by a sliding joint.

[0009] An electrical switching device according to the invention thus comprises at least one movable switching element. The invention is particularly advantageous when the switching device comprises several movable switching elements, because it allows the switching elements to be driven independently of one another by a switching drive via a guide element that is connected to each switching element by a kinematic chain.

[0010] In one embodiment of the invention, each switching element is mounted in the housing for linear movement. In other words, the switching movements of the switching elements are translational movements.

[0011] In a further embodiment of the invention, each switching element is designed as a switching pin, and the contact element corresponding to the switching pin has an opening configured to receive one end of the switching pin. According to this embodiment of the invention, each fixed contact element is a so-called tulip contact, into which the corresponding movable switching element is inserted to close a current path between the main conductor and the fixed contact element.

[0012] In a further embodiment of the invention, the guide element is arranged within the housing. This eliminates the need to extend the kinematic chains that connect the movable switching elements to the guide element outside the housing, which would be difficult to achieve, especially in the case of gas-tight housings.

[0013] In a further embodiment of the invention, the guide element is mounted so as to be rotatable about a rotational axis, and the switching drive is configured to rotate the guide element about the rotational axis. For example, each kinematic chain coupling a switching element to the guide element has a first lever arm which, together with the guide element, forms a cam mechanism. The guide element is, for example, a cam with at least one cam groove, and each first lever arm has a coupling lug guided in a cam groove of the guide element. Even if the switching device has multiple switching elements, the guide element can be a cam with only one cam groove, and each first lever arm can have a coupling lug guided in the cam groove of the guide element.By means of a suitable design of the guide element or its cam groove or cam grooves, in particular several switching elements can be moved independently of one another, so that different switching states can be realized.

[0014] In a further embodiment of the invention, each kinematic chain coupling a switching element to the guide element has a second lever arm that connects the first lever arm and the switching element to one another and is connected to the first lever arm by a second pivot joint. The second lever arm is, for example, part of the connecting assembly that connects the switching element to the main conductor via a first pivot joint and a sliding joint, and is connected to the switching element by the first pivot joint. The connecting assembly has a connecting link that is connected to the second lever arm by the second pivot joint and coupled to the main conductor by a linear guide.Furthermore, the linear guide has, for example, a linear guide groove for each connecting assembly, and the connecting link of the connecting assembly has a groove engagement that is guided in the linear guide groove, thereby forming the sliding joint connecting the connecting assembly to the main conductor. Every second lever arm is therefore, for example, part of both a kinematic chain that connects a movable switching element to the guide element and the connecting assembly that connects the switching element to the main conductor. This advantageously reduces the number of components of the switching device that form the kinematic chains and the connecting assemblies, and saves installation space compared to an independent implementation of the kinematic chains and connecting assemblies.

[0015] In a further embodiment of the invention, the switching device has a first switching element and a second switching element, and the guide element is movable between three positions. In a first position, both switching elements assume their first switching position; in a second position, the first switching element assumes its first switching position and the second switching element assumes its second switching position; and in a third position, the second switching element assumes its first switching position and the first switching element assumes its second switching position. The first switching element and the second switching element are mounted in the housing so as to be linearly movable, for example, along a common movement axis.If the guide element is designed, for example, as a cam disc with a cam disc groove, the cam disc groove is designed, for example, such that the second position of the cam disc is reached by rotating the cam disc from the first position by a certain angle of rotation in a first direction of rotation and the third position of the cam disc is reached by rotating the cam disc from the first position by the angle of rotation in a second direction of rotation opposite to the first direction of rotation.

[0016] In a further embodiment of the invention, the housing is designed to be gas-tight. This makes it possible, in particular, to design the switching device as a module of a gas-insulated switchgear assembly. However, in other embodiments of the invention, the housing need not be gas-tight.

[0017] In a further embodiment of the invention, the housing has a first feedthrough for the main conductor, through which a main conductor terminal is passed, which is electrically connected to the main conductor and via which the main conductor can be contacted outside the housing. Furthermore, the housing has a further feedthrough for each contact element, through which a contact terminal is passed, which is electrically connected to the contact element and via which the contact element can be contacted outside the housing. This embodiment of the invention enables the electrical connection of the main conductor and each fixed contact element to electrical conductors arranged outside the housing via the main conductor terminal or contact terminal. This is also an optional embodiment of the invention.In other embodiments, the housing could, for example, be coupled to an adjacent module of a gas-insulated switchgear, with the main conductor being part of a main current path that runs through the switching device and the adjacent module. In such a case, the housing of the switching device does not need to have a special feedthrough for the main conductor.

[0018] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the drawings. Fig. 1 a sectional view of an embodiment of an electrical switching device in a first switching state, Fig. 2 a sectional view of the Fig. 1 shown electrical switching device in a second switching state, Fig. 3 a sectional view of the Fig. 1 shown electrical switching device in a third switching state, Fig. 4 a sectional view of the Fig. 1 shown electrical switching device in a sectional plane which corresponds to the sectional plane of the Fig. 1 to 3 is orthogonal, Fig. 5 a perspective view of kinematic components of the Fig. 1 shown electrical switching device.

[0019] Corresponding parts are provided with the same reference numerals in the figures.

[0020] The figures show an embodiment of an electrical switching device 1. The switching device 1 comprises - a housing 3, - a main electrical conductor 5 fixedly arranged in the housing 3, - a first electrical contact element 7 fixedly arranged in the housing 3, - a second electrical contact element 8 fixedly arranged in the housing 3, - a first switching element 9 which is arranged movably in the housing 3 and is associated with the first electrical contact element 7, - a second switching element 10 arranged movably in the housing 3, which is associated with the second electrical contact element 8, - a guide element 12 mounted in the housing 3 so as to be rotatable about an axis of rotation 11, - for each switching element 9, 10, a kinematic chain 13, by which the switching element 9, 10 is coupled to the guide element 12, so that movements of the switching element 9, 10 can be effected by rotations of the guide element 12 about the axis of rotation 11, - a switching drive 14 which is designed to cause rotations of the guide element 12 about the rotation axis 11, - for each switching element 9, 10, a connecting assembly 15 which electrically connects the switching element 9, 10 to the main conductor 5 and for this purpose is connected to the switching element 9, 10 by a first rotary joint 16 and to the main conductor 5 by a sliding joint 17.

[0021] The switching elements 9, 10 are mounted in the housing 3 so as to be linearly movable along a common movement axis 18. Each switching element 9, 10 is designed as a switching pin.

[0022] Each electrical contact element 7, 8 has an opening 19 facing the associated switching element 9, 10, which is configured to receive one end of the associated switching element 9, 10. The openings 19 of the two electrical contact elements 7, 8 are located opposite each other along the movement axis 18 and face each other.

[0023] The guide element 12 is a cam disc with a curved cam disc groove 20.

[0024] Each kinematic chain 13, by which a switching element 9, 10 is coupled to the guide element 12, has a first lever arm 21 and a second lever arm 22. The first lever arm 21 has a coupling lug 23 guided in the cam groove 20 of the guide element 12 and forms a cam mechanism with the guide element 12. The first lever arm 21 and the second lever arm 22 are connected to each other by a second pivot joint 24. The second lever arm 22 is also part of the connecting assembly 15, which connects the switching element 9, 10 to the main conductor 5 via a first pivot joint 16 and a sliding joint 17, and is connected to the switching element 9, 10 by the first pivot joint 16. In addition to the second lever arm 22, the connecting assembly 15 has a connecting member 25 which is connected to the second lever arm 22 by the second pivot joint 24 and is coupled to the main conductor 5 via a linear guide 26.The second pivot joint 24 thus rotatably couples the second lever arm 22 to both the first lever arm 21 and the connecting link 25.

[0025] The linear guide 26 has a linear guide groove 27 for each connecting assembly 15, and the connecting link 25 of the connecting assembly 15 has a groove engagement 28 that is guided in the linear guide groove 27, thereby forming the sliding joint 17 connecting the connecting assembly 15 to the main conductor 5. The linear guide 26 is essentially designed as a plate having recesses forming the linear guide grooves 27. Each connecting link 25 is fork-shaped with two fork tines 29 that are arranged on opposite sides of the linear guide 26 and are connected to one another by the groove engagement 28. The groove engagement 28 is connected to each fork tine 29 by a third pivot joint 30, so that the fork tines 29 can be rotated about a pivot axis 31 that runs between them through the groove engagement 28.Since the second lever arm 22 of each kinematic chain 13, by which a switching element 9, 10 is coupled to the guide element 12, is also part of the connecting assembly 15 which connects this switching element 9, 10 to the main conductor 5, the kinematic chain 13 and the connecting assembly 15 can also be referred to as a higher-level kinematic chain by which the switching element 9, 10 is coupled to the guide element 12 and the main conductor 5.

[0026] The guide element 12 can be rotated between three positions by the switching drive 14, which positions result in different switching states of the switching elements 9, 10 due to the design of the cam disk groove 20. In a first switching state, each switching element 9, 10 rests on the contact element 7, 8 to which it is assigned and is electrically connected to this contact element 7, 8. In a second switching state, the first switching element 9 rests on the first contact element 7 and is electrically connected thereto, and the second switching element 10 is separated from the second contact element 8. In a third switching state, the second switching element 10 rests on the second contact element 8 and is electrically connected thereto, and the first switching element 9 is separated from the first contact element 7.

[0027] Fig. 1 ( Fig. 1) shows a sectional view of the electrical switching device 1 in the first switching state.

[0028] Fig. 2 ( Fig. 2) shows a sectional view of the electrical switching device 1 in the second switching state in a Fig. 1 corresponding section plane. The second switching state is realized by rotating the guide element 12 relative to its position in the first switching state in a first direction of rotation.

[0029] Fig. 3 ( Fig. 3) shows a sectional view of the electrical switching device 1 in the third switching state in a Fig. 1 corresponding section plane. The third switching state is realized by rotating the guide element 12 relative to its position in the first switching state in a second direction of rotation opposite to the first direction of rotation.

[0030] Fig. 4 ( Fig. 4) shows a section of a sectional view of the electrical switching device 1 in a sectional plane which is perpendicular to the sectional plane of the Fig. 1 to 4.

[0031] Fig. 5 ( Fig. 5) shows a perspective view of kinematic components of the Fig. 1 shown electrical switching device 1.

[0032] The first lever arm 21 of each linear chain 13 is coupled to the housing 3 by a pin-like connecting element 32, which enables movement of the first lever arm 21 relative to the housing 3 along a longitudinal axis of the connecting element 32.

[0033] The switching drive 14 is arranged outside the housing 3 and drives the guide element 12 via a drive shaft 33 which is guided into the housing 3 and has a drive shaft head 34 which is firmly connected to the guide element 12.

[0034] The housing 3 has a first feedthrough 35 for the main conductor 5, through which a main conductor terminal 36 is led, which is electrically connected to the main conductor 5 and via which the main conductor 5 can be contacted outside the housing 3. The first feedthrough 35 has a first electrical insulation 37, by which the main conductor 5 is electrically insulated from the housing 3. Furthermore, the housing 3 has a second feedthrough 38 for the first contact element 7, through which a first contact terminal 39 is led, which is electrically connected to the first contact element 7 and via which the first contact element 7 can be contacted outside the housing 3. The second feedthrough 38 has a second electrical insulation 40, by which the first contact element 7 is electrically insulated from the housing 3.In addition, the housing 3 has a third feedthrough 41 for the second contact element 8, through which a second contact terminal 42 is passed, which is electrically connected to the first contact element 7 and via which the second contact element 8 can be contacted outside the housing 3. The third feedthrough 40 has a third electrical insulation 43, by which the second contact element 8 is electrically insulated from the housing 3.

[0035] Furthermore, a first electrical shield 44 is arranged in the housing 3 for each contact element 7, 8, which surrounds the contact element 7, 8. Furthermore, second electrical shields 45 are arranged in the housing 3, each surrounding an area through which the switching elements 9, 10 extend in each of the three switching states.

[0036] The housing 3 further comprises a rupture disc 47 which is designed such that it is destroyed in the event of an overpressure in the housing 3 if this overpressure exceeds a predetermined threshold value.

[0037] Although the invention has been illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 771 896 B1

[0004]

Claims

[1] Electrical switching device (1), comprising - a housing (3), - a main electrical conductor (5) fixedly arranged in the housing (3), - at least one electrical contact element (7, 8) fixedly arranged in the housing (3), - for each contact element (7, 8), a switching element (9, 10) arranged in the housing (3) which is movable between a first switching position in which it rests against the electrical contact element (7, 8) and is electrically connected to the electrical contact element (7, 8), and a second switching position in which it is separated from the electrical contact element (7, 8), - a movably mounted guide element (12), - for each switching element (9, 10), a kinematic chain (13) by which the switching element (9, 10) is coupled to the guide element (12), so that movements of the guide element (12) cause movements of the switching element (9, 10), - a switching drive (14) which is arranged to move the guide element (12), and - for each switching element (9, 10), a connecting assembly (15) which electrically connects the switching element (9, 10) to the main conductor (5) and for this purpose is connected to the switching element (9, 10) by a first rotary joint (16) and to the main conductor (5) by a sliding joint (17). [2] Switching device (1) according to claim 1, wherein each switching element (9, 10) is mounted in the housing (3) so as to be linearly movable. [3] Switching device (1) according to claim 1 or 2, wherein each switching element (9, 10) is designed as a switching pin and the contact element (7, 8) corresponding to the switching pin has an opening (19) which is designed to receive one end of the switching pin. [4] Switching device (1) according to one of the preceding claims, wherein the guide element (12) is arranged in the housing (3). [5] Switching device (1) according to one of the preceding claims, wherein the guide element (12) is mounted rotatably about an axis of rotation (11) and the switching drive (14) is arranged to rotate the guide element (12) about the axis of rotation (11). [6] Switching device (1) according to claim 5, wherein each kinematic chain (13) coupling a switching element (9, 10) to the guide element (12) has a first lever arm (21) which forms a cam mechanism with the guide element (12). [7] Switching device (1) according to claim 6, wherein the guide element (12) is a cam disc with at least one cam disc groove (20) and each first lever arm (21) has a coupling nose (23) guided in a cam disc groove (20) of the guide element (12). [8] Switching device (1) according to claim 6 with a plurality of switching elements (9, 10), wherein the guide element (12) is a cam disc with exactly one cam disc groove (20) and each first lever arm (21) has a coupling nose (23) guided in the cam disc groove (20) of the guide element (12). [9] Switching device (1) according to one of claims 6 to 8, wherein each kinematic chain (13) coupling a switching element (9, 10) to the guide element (12) has a second lever arm (22) which connects the first lever arm (21) and the switching element (9, 10) to one another and is connected to the first lever arm (21) by a second rotary joint (24). [10] Switching device (1) according to claim 9, wherein the second lever arm (22) is part of the connecting assembly (15) which connects the switching element (9, 10) to the main conductor (5) via a first rotary joint (16) and a sliding joint (17), and is connected to the switching element (9, 10) by the first rotary joint (16), and wherein the connecting assembly (15) has a connecting member (25) which is connected to the second lever arm (22) by the second rotary joint (24) and is coupled to the main conductor (5) by a linear guide (26). [11] Switching device (1) according to claim 10, wherein the linear guide (26) has a linear guide groove (27) for each connecting assembly (15) and the connecting member (25) of the connecting assembly (15) has a groove engagement (28) which is guided in the linear guide groove (27), whereby the sliding joint (17) connecting the connecting assembly (15) to the main conductor (5) is formed. [12] Switching device (1) according to one of the preceding claims, having a first switching element (9) and a second switching element (10), wherein the guide element (12) is movable between three positions, wherein in a first position both switching elements (9, 10) assume their first switching position, in a second position the first switching element (9) assumes its first switching position and the second switching element (10) assumes its second switching position, and in a third position the second switching element (10) assumes its first switching position and the first switching element (9) assumes its second switching position. [13] Switching device (1) according to claim 12, wherein the first switching element (9, 10) and the second switching element (9, 10) are mounted in the housing (3) so as to be linearly movable along a common movement axis (18). [14] Switching device (1) according to one of the preceding claims, wherein the housing (3) is gas-tight. [15] Switching device (1) according to one of the preceding claims, wherein the housing (3) has a first feedthrough (35) for the main conductor (5), through which a main conductor terminal (36) electrically connected to the main conductor (5) is led, via which the main conductor (5) can be contacted outside the housing (3), and wherein the housing (3) has a further feedthrough (38, 41) for each contact element (7, 8), through which a contact terminal (39, 42) electrically connected to the contact element (7, 8) is led, via which the contact element (7, 8) can be contacted outside the housing (3).

Images