Drive unit for driving switching contacts of a high-voltage circuit breaker

Abstract

The invention relates to a drive unit (10) for driving switching contacts of a high-voltage circuit breaker (50), comprising an operating element (12), a plurality of actuating elements (16, 18, 20) for actuating the switching contacts, at least two of which actuating elements (16, 18, 20) are arranged at a distance from one another with respect to an axis (24), and a mechanism (22), in particular lever mechanism, for translating a movement of the operating element (12) into corresponding movements of the actuating elements (16, 18, 20), wherein the mechanism (22) comprises at least one shaft (26), which is rotatably mounted on the axis (24), for translating the movement of the operating element (12) into the corresponding movement of at least one actuating element (18, 20) which is arranged at a distance from the operating element (12) in the axial direction of the axis (24). Provision is made for the drive unit (10) to further have a compensating coupling device (36) for compensating for a delay in the translation of movement between at least two actuating elements (16, 18, 20) from amongst the actuating elements (16, 18, 20) which are arranged at a distance from one another with respect to the axis (24).

Description

[0001] The invention relates to a drive unit for driving switching contacts of a high-voltage circuit breaker, comprising (i) an actuating element, (ii) several actuating elements for positioning the switching contacts, of which at least two actuating elements are spaced apart from each other with respect to an axis, and (iii) a mechanism, in particular a lever mechanism, for transmitting a movement of the actuating element into corresponding movements of the actuating elements, wherein the mechanism comprises at least one shaft rotatably mounted on the axis for transmitting the movement of the actuating element into the corresponding movement of at least one actuating element spaced apart from the actuating element in the axial direction of the axis.

[0002] DE 10 2018 205 910 A1 discloses a single-pole high-voltage circuit breaker in a dead-tank design, comprising a switching unit, a switching resistor unit, and a drive unit for actuating the switching contacts of the switching unit and the switching resistor unit. The longitudinal axes of the switching unit and the switching resistor unit, along which the respective switching contacts also move, are spaced apart from each other. The drive unit has (i) an actuating element axially movable with respect to a longitudinal axis of the switching unit, (ii) positioning elements spaced apart with respect to a transverse axis for positioning the switching contacts, and a mechanism for transmitting a movement of the actuating element into corresponding movements of the positioning elements.The mechanism comprises at least one shaft rotatably mounted on the axis for transmitting the movement of the actuating element into the corresponding movement of the adjusting element for the switching contact of the turn-on resistor unit, which is arranged offset from the axis of the actuating element. The movement of the switching contact of the switching unit, not shown directly in this document, is generated, for example, directly from the movement of the actuating element via a rigid intermediate element. In such applications, however, it is not critical if the switching of the switching elements does not occur precisely at the same time or with a well-defined delay.

[0003] The switching movements involved in driving the contacts of a high-voltage circuit breaker are very rapid. Therefore, the onset of the switching movement results in sudden forces and consequently very high accelerations. When transmitting this motion via the rotation of a shaft or similar component, the problem arises that inertia leads to shaft torsion. This means that when transmitting motion over a section of the shaft, the length of that section results in a delay in the transmission of the motion. This is significantly more critical in a multi-pole high-voltage circuit breaker, where, for example, the switching contacts of the breaker units of the individual poles are switched via such a drive unit.

[0004] German patent application DE 199 13 059 A1 discloses a high-voltage circuit breaker with three poles, each pole having at least one interrupter unit whose actuated switching contact can be actuated by a switching rod via a common switch actuator such that, during a switching operation, a time-delayed closing occurs at least between the interrupter units of two poles, with at least the switching rod of a first pole being connected to the switch actuator via a lever. To achieve a time-delayed closing of the interrupter unit of a pole or of the interrupter units from pole to pole during the switching operation, only the switching rod of the second and / or third pole is connected to the switch actuator by means of spring elements that are compressible during a switching operation and expand after contact is made.

[0005] From PCT publication WO 2017 / 162405, a circuit breaker is known which comprises three parallel switching rods, each of which is movable along its longitudinal axis to open and close a switching contact of the circuit breaker. A common drive serves to move the three switching rods simultaneously. The movement is redirected via rotatably mounted levers.

[0006] From PCT publication WO 2017 / 162404, a circuit breaker is known which comprises three parallel switching rods, each of which is movable along its longitudinal axis to open and close a switching contact of the circuit breaker. A common drive serves to move the three switching rods simultaneously. The switching rods are coupled to the common drive via a gearbox. The switching rods are connected to the common drive via a crossbeam of the gearbox.

[0007] Starting from the aforementioned inertia problem in connection with a shaft, the invention is based on the objective of providing a drive unit with a shaft for motion transmission in which the drive of the actuating elements arranged at a distance from each other on the axis can be precisely synchronized.

[0008] The problem is solved according to the invention by the features of independent claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

[0009] In the drive unit according to the invention for driving switching contacts of a high-voltage circuit breaker, which comprises (i) an actuating element, (ii) several actuating elements for positioning the switching contacts, of which at least two actuating elements are arranged spaced apart from each other with respect to an axis, and (iii) a mechanism, in particular a lever mechanism, for transmitting a movement of the actuating element into corresponding movements of the actuating elements, wherein the mechanism comprises at least one shaft rotatably mounted on the axis for transmitting the movement of the actuating element into the corresponding movement of at least one actuating element spaced apart from the actuating element in the axial direction of the axis, it is provided thatthat this drive unit further comprises a compensating coupling device for compensating for a delay in the motion transmission between at least two actuating elements of the actuating elements arranged at a distance from each other with respect to the axis. In particular, the mechanics comprise the compensating coupling element.

[0010] The compensating coupling device is used in particular as a push and / or pull rod. It therefore "replaces" a rigid coupling rod (push and / or pull rod) that would otherwise be used.

[0011] According to a preferred embodiment of the invention, the compensating coupling device comprises a spring arrangement with at least one spring element, in particular a disc spring. This spring element serves as a temporary energy storage device and provides a delay in the energy or force transmission. Alternatively, the compensating coupling device comprises a different energy storage arrangement with at least one energy storage element.

[0012] It is specifically provided that the compensating coupling device continues to include means for pre-tensioning the at least one spring element. These means are specifically designed to allow for adjustable pre-tensioning of the at least one spring element.

[0013] Furthermore, it is advantageously designed that different delays can be achieved with a preselected number and / or shape of spring elements or energy storage elements. This allows for variable adjustment of the movement patterns. Among other things, the on and off movements can be set independently and variably. For this purpose, for example, spring elements with different spring constants are used and / or the spring travel of the individual spring elements is specifically defined.

[0014] According to a further preferred embodiment of the invention, one of the actuating elements is positioned without a gap relative to the actuating element with respect to the axis alignment of the axis. Therefore, the torsion or inertia problems associated with the shaft do not occur during the transmission of motion to this actuating element.

[0015] In this design, it is particularly important that the compensating coupling device is arranged in a transmission path between the actuating element and the positioning element, which has no distance relative to the actuating element with respect to the axis. The compensation takes place in this transmission path.

[0016] According to yet another preferred embodiment of the invention, the mechanism, designed as a lever mechanism, comprises a main lever arranged on the shaft, which is coupled to the actuating element, and at least one further lever axially spaced with respect to the main lever. These levers are generally used as deflection levers.

[0017] It is advantageously provided that the actuating element, the main lever, the compensating coupling device, and the adjusting element, which is axially free of any distance to the actuating element, are arranged in one plane. The transmission path in this plane does not run axially across the shaft and can be implemented solely via a type of linkage.

[0018] In connection with the aforementioned lever mechanism design, it is provided that the compensating coupling device is directly coupled to the main lever.

[0019] Furthermore, it is advantageously provided that the main lever is designed as a double-sided lever. Preferably, the actuating element is coupled to one side and the compensating coupling device and the adjusting element, which is axially free of gaps relative to the actuating element, are coupled to the other side.

[0020] Another embodiment of the invention provides that a lever - preferably used as a deflection lever - is further arranged in the transmission path between the actuating element and the actuating element which is axially free of distance from the actuating element.

[0021] The invention further relates to a high-voltage circuit breaker with at least two switching poles, in particular in a three-pole design, and a drive unit mentioned above for driving switching contacts of the high-voltage circuit breaker.

[0022] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more readily understandable in connection with the following description of an exemplary embodiment, which is explained in more detail in conjunction with the drawings. These drawings show: Fig. 1 a drive unit for driving switching contacts of a high-voltage circuit breaker according to a preferred embodiment of the invention, Fig. 2 the drive unit in a sectional view in which the section plane passes through a compensating coupling device of the drive unit, Fig. 3 details of the compensating coupling device, Fig. 4 the drive unit and a drive actuator and Fig. 5 a part of the high-voltage circuit breaker with the drive unit and the drive actuator.

[0023] The Fig. 1 shows a drive unit 10 for driving switching contacts of a device in Fig. 5 High-voltage circuit breaker 50 in multi-pole design, at least partially shown.

[0024] The drive unit 10 comprises an actuating element 12, a drive actuator 14 that drives the actuating element 12, several (here in this example three) positioning elements 16, 18, 20 for setting the switching contacts, and a mechanism 22 designed as a lever mechanism for transmitting a movement of the actuating element 12 into corresponding movements of the positioning elements 16, 18, 20. Central elements of the mechanism 22 are a shaft 26 rotatably mounted on an axis 24 and a main lever 28 fixedly or at least rotationally fixed to this shaft 26. This main lever 28 is designed as a lever with two sides relative to the axis 24. Furthermore, the mechanism 22 comprises three levers 30, 32, 34, each assigned to one of the actuating elements 16, 18, 20, as well as a compensating coupling device 26 acting in the manner of a connecting rod, i.e. as a pull and / or push rod. The actuating element 12 acts directly on the main lever 28, more precisely on one side of the main lever 28.The three levers 30, 32, 34 function as deflection levers in the drive unit 10.

[0025] One of the actuating elements 16 is axially free of distance to the main lever 28 with respect to the axis alignment of the axis 24. The actuating element 12, the main lever 28, the compensating coupling device 36, and this actuating element 16, which is axially free of distance to the actuating element 12 and the main lever, are arranged in a plane perpendicular to the axis 24. The motion transmission between the actuating element 12 and this actuating element 16 occurs via a linkage arrangement only, and not via the shaft 26. The corresponding linkage arrangement is formed by the main lever 28, the compensating coupling device 26, and one of the three levers 30.

[0026] The other two of the three levers, 32 and 34, are arranged axially spaced from the main lever 28 on the shaft 26 and are fixedly or at least rotationally fixed to it. The actuating elements 18 and 20, which are assigned to these levers 32 and 34 (hereinafter referred to as "the other actuating elements"), are also arranged axially spaced from the main lever 28.

[0027] Thus, all three actuating elements 16, 18, 20 for setting the switching contacts are arranged at intervals from one another with respect to the axis 24, wherein one of the actuating elements 16 has no distance with respect to the axis 24 relative to the actuating element 12, and the other actuating elements 18, 20 and their associated levers 32, 34 are arranged to the right and left of the plane with the main lever 28 with respect to the axis alignment of the axis 24. The distance between the other actuating elements 18, 20 and their associated levers 32, 34 is the same (in magnitude) in this example.

[0028] The compensating coupling device 36 serves to compensate for a delay in the transmission of motion between the actuating element 16, which is controlled more directly via the linkage arrangement, and the other actuating elements 18, 20, which are controlled with a slight delay via the shaft 26 due to inertial torsion. The compensating coupling device 36 has a spring arrangement 38 with at least one spring element (in this example, two disc springs). This serves as a temporary energy storage device and causes a delay in the transmission of energy or force to the actuating element 16. The compensating coupling device 36 is used here as a connecting rod (push and / or pull rod) and thus "replaces" a rigid connecting rod that would otherwise be used.

[0029] The compensating coupling device 36 consists of two rod sections arranged one behind the other on a common axis and coupled via the spring assembly 38. The two spring elements 42, designed as disc springs, are threaded onto a pin-like axle element 40 of one rod section, with a portion of a cage 44 of the other rod section, which overlaps one of the spring elements 42, arranged between the two spring elements 42. Furthermore, the compensating coupling device 36 has means for pre-tensioning at least one of the spring elements 42. These means are specifically designed to allow for adjustable pre-tensioning of the spring elements 42. In this case, these means are designed to be particularly simple. The pin-like axle element 40 has an external thread, which, together with at least one nut or other mating element, forms a screw connection 46 via which the spring elements 42 can be adjustedly pre-tensioned.

[0030] The Fig. 2 Figure 1 shows the drive unit 10 in a sectional view, in which the section plane is the aforementioned plane in which the actuating element 12, the main lever 28, the compensating coupling device 36 and the actuating element 16, which is axially free of gaps relative to the actuating element 12 and the main lever, are arranged.

[0031] Fig. 3 Figure 3 shows details of the compensating coupling device 36. This illustration clearly shows that the compensating coupling device 36 is used as a connecting rod in the linkage assembly. The two rod sections arranged one behind the other on the common axis and coupled via the spring assembly 38 are also clearly visible. The two spring elements 42 are arranged on the pin-like axle element 40 of one rod section, with an element of the other rod section positioned between the two spring elements 42. Furthermore, the screw connection 46 formed by the pin-like axle element 40 with its external thread and nuts is clearly visible.

[0032] The Fig. 4 Figure 10 shows the drive unit 10 together with a large part of the drive actuator 14, which is designed as a spring storage drive, in a side view.

[0033] The Fig. 5Finally, the drive unit 10 and the drive actuator 14 are shown at one end of the switching unit 48 of the corresponding high-voltage circuit breaker 50. In this case, the circuit breaker has a dead-tank design.

[0034] In the following, important features of the invention will be discussed again in other words with reference to the embodiment shown.

[0035] The force exerted by the drive actuator 14 on the main lever 28 sets the shaft 26 into a rotational motion. Due to the high forces and speeds, a twist angle occurs at the levers 32 and 34 at the ends of the shaft 26, caused by the moment of inertia of the shaft 26.

[0036] If lever 30 is directly coupled to the main lever 28 – for example, via a rigid coupling device – there is a direct transmission of force. With the other levers 32 and 34, the force applied by the spring-loaded actuator is delayed due to the angle of rotation of shaft 26. Thus, levers 30, 32, and 34 are moved with different starting points or speeds, resulting in different galvanic contact times between the different poles.

[0037] To solve the problem, instead of a rigid coupling, a coupling is used that reacts with a delay to the force applied by the spring accumulator. This coupling is formed by the compensating coupling device 36.

[0038] Depending on the rotation angle of the shaft 26, the coupling 36 is decoupled by spring elements 42 (here, disc springs). The spring travel and the subsequent block of spring elements 42 thus allow for the generation of any desired delay, particularly in the millisecond range (ms range). This delay is possible in both OFF and ON directions, or just OFF or ON. Therefore, the delayed response of levers 32 and 34 can be synchronized with the response of lever 30.

Claims

1. A drive unit (10) for driving switching contacts of a high-voltage circuit breaker (50), with: - an operating element (12), - multiple actuating elements (16, 18, 20) for actuating the switching contacts, of which at least two actuating elements (16, 18, 20) are arranged spaced apart from one another relative to an axis (24), and - a mechanism (22), in particular a lever mechanism, for transmission of a movement of the operating element (12) into corresponding movements of the actuating elements (16, 18, 20), wherein the mechanism (22) comprises at least one shaft (26) rotatably mounted on the axis (24) for transmission of the movement of the operating element (12) into the corresponding movement of at least one actuating element (18, 20) arranged spaced apart from the operating element (12) in the axial direction of the axis (24), characterised by a compensating coupling device (36) for compensating a delay of the movement transmission between at least two actuating elements (16, 18, 20), resulting from the respective distance of the actuating elements (16, 18, 20) arranged spaced apart from one another relative to the axis (24) to a actuating element (16, 18, 20) not having a distance from the operating element (12) relative to the axial direction of the axis (24) and the torsion of the shaft (26) during the movement mentioned above.

2. The drive unit according to claim 1, characterised in that the compensating coupling device (36) has a spring assembly (38) with at least one spring element (42).

3. The drive unit according to claim 2, characterised in that the compensating coupling device (36) has means (46) for biasing the at least one spring element (42).

4. The drive unit according to any one of claims 1 to 3, characterised in that one of the actuating elements (16) has no distance from the operating element (12) relative to the axis (24).

5. The drive unit according to claim 4, characterised in that the compensating coupling device (36) is arranged in a transmission path between the operating element (12) and the actuating element (16) which has no distance from the operating element (12) relative to the axis (24).

6. The drive unit according to any one of claims 1 to 5, characterised in that the mechanism (22) configured as a lever mechanism has - a main lever (28) which is arranged on the shaft (26) and is coupled to the operating element (12), and - at least one further lever (32, 34) axially spaced apart relative to the main lever (28).

7. The drive unit according to claim 6, characterised in that the operating element (12), the main lever (28), the compensation coupling device (36), and the actuating element (16) having no axial distance from the operating element (12) are arranged in one plane.

8. The drive unit according to claim 6 or 7, characterised in that the compensation coupling device (36) is coupled directly to the main lever (28).

9. The drive unit according to any one of claims 6 to 8, characterised in that the main lever (28) is configured as a two-sided lever.

10. The drive unit according to any one of claims 5 to 9, characterised in that a lever (30) is further arranged in the transmission path between the operating element (12) and the actuating element (16) having no axial distance from the operating element (12).

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