Electric remote drive, remote drive arrangement and remote drive unit for actuating an electrical switching device with rotary force absorption

Abstract

Electric remote drive (2) for actuating an electric switching device (4) with rotary force reception via a switching shaft (5), with two independently controllable actuators (6) designed as electromagnets (6) acting oppositely on a slidably mounted slide (10), characterized in that that the slide (10) has a trough-shaped recess (12) for carrying a first lever arm (21) of a rocker arm (20) mounted about a rocker arm pivot axis (23), the second lever arm (22) of which has a recess (24) at its end, into which a pin (31) of a crank (30) engages, which can be positively connected (32) to the shift shaft (5) and has an arc-shaped elongated hole (33) through which the rocker arm pivot axis (23) runs, wherein the rocker arm pivot axis (23) is axially offset circumferentially as a section-wise roof-shaped contour (26), on which a leaf spring (25) rests for fixing a shift position.

Description

[0001] The invention relates to an electric remote drive for actuating an electric switching device with rotary force absorption via a switching shaft, with two independently controllable actuators which are designed as electromagnets and act oppositely on a slidably mounted slide.

[0002] A secure and reliable power supply is the fundamental prerequisite for smooth and economical operation in private, public, and especially industrial environments. The increasing complexity of electrical systems necessitates appropriate protective measures to meet the requirements for reliability and electrical safety.

[0003] For standards-compliant construction and to ensure a reliable power supply, the electrical system is equipped with switching devices such as overcurrent protection devices, circuit breakers, or load break switches. With regard to system availability and electrical safety, the electrical system must remain controllable even if part of the power supply is no longer guaranteed, for example, due to a partial network failure.

[0004] The electrically isolated structure between the switching device on the one hand and a drive for the switching device on the other hand thus allows the switching device to be switched by means of a remotely controlled drive (remote drive) in conjunction with an independent and remotely available power source.

[0005] Particularly in medical settings, the VDE 0100-710 standard imposes further requirements on the power supply system beyond insulation monitoring, especially regarding the rapid tripping of switching devices. For example, switching times of less than 500 ms must be achieved in the event of a power failure.

[0006] Remote drives for switching control are known from the prior art, based on electric motors as actuators, but these do not meet the switching times required by standards. Furthermore, remote drives are available that, while featuring electromagnetically controlled actuators, are driven by only a single control voltage source and therefore do not guarantee the required reliability. Fast-switching remote drives are also known that operate with a spring accumulator or electromagnet; however, these have very complex mechanics and are not suitable for integrating and expanding the switching device.

[0007] Among the known remote drives are designs that exert a power transmission to the switching device in such a way that the switching knob of the switching device is moved via a drive rail of the remote drive.

[0008] For example, the patent application DE 2019 122 978 A1 shows a remote drive in which two independently controllable electromagnets act on a slidably mounted slide, but the force is received at the switching device via its switching knob.

[0009] Switching devices currently on the market, such as motor-driven load break switches with integrated drive or load break switches designed for external drives, have a switching shaft for rotary force absorption and therefore often do not have a switching knob.

[0010] German patent application DE 10 2021 116 591 A1 describes a drive for actuating an electrical switching device with rotary force absorption via a rotatable control shaft (switching shaft). However, two electromagnets arranged perpendicular and transverse to the control shaft of the switching device require two movable drivers which drive the switching shaft via a rack and pinion drive or via a switching cam connected to the switching shaft.

[0011] The present invention is therefore based on the objective of designing an electric remote drive for actuating an electric switching device with rotary force absorption, which is compact in design, enables fast switching times and can be integrated into a unit with switching devices.

[0012] This problem is solved in conjunction with the features of the preamble of claim 1 by the fact that the slide has a trough-shaped recess for carrying a first lever arm of a rocker arm mounted about a rocker arm pivot axis, the second lever arm of which has a recess at its end into which a pin of a crank engages, which can be positively connected to the switching shaft and has an arc-shaped elongated hole through which the rocker arm pivot axis runs, wherein the rocker arm pivot axis is axially offset circumferentially as a section-wise roof-shaped contour on which a leaf spring rests for fixing a switching position.

[0013] As a prerequisite, the electrical switching device has a switching shaft via which, according to the requirements of the invention, a torque is transmitted from the remote drive to the switching device to actuate the switching action. In this embodiment, the invention comprises only the remote drive itself and not the electrical switching device.

[0014] Starting from two axially opposed electromagnets with rod-shaped armatures, which move the sliding carriage, the power flow passes through a drive mechanism consisting of a rocker arm. The first lever arm of the rocker arm engages with the carriage, and the second lever arm moves a crank, which exerts a torque on the shift shaft of the switching device. The axis of rotation of the crank coincides with the axis of the shift shaft and drives it via a positive-locking shaft-hub connection. A leaf spring, resting on the roof-shaped contour of the rocker arm's pivot axis, serves to fix the switching position.

[0015] The conversion of the slide's translational movement into the rotary movement required to drive the switching shaft is achieved in a compact design via the rocker arm and crank. This allows the remote drive according to the invention to be mounted directly next to a standard switching device, in order to provide remote operation as an additional function. Alternatively, it is also possible to combine it with the switching device to form an integrated electrical remote drive arrangement.

[0016] The two independently controllable, galvanically isolated actuators allow them to be powered from two independent power supply networks. Furthermore, the electromagnets operate very quickly, resulting in standard-compliant short switching times. The electromagnets are preferably designed as pull magnets.

[0017] In a further embodiment, the electric remote drive features a switch knob that can be axially attached to the rocker arm pivot axis for manual switching.

[0018] A shift knob can be axially mounted onto the rocker arm pivot of the remote drive to enable manual switching in emergency operation. Power transmission to the rocker arm pivot is achieved via a positive-locking shaft-hub profile.

[0019] Advantageously, the sled has a rib-like projection with a break along one edge on its longitudinal side.

[0020] A rib-like projection is formed on one longitudinal edge – relative to the direction of movement – ​​of the slide, such that when the slide is rotated 180° about its longitudinal axis, two opposing slides can be arranged symmetrically, with the projections offset vertically in the plane of symmetry. Note: The terms "symmetrical" and "mirror-image symmetrical" will continue to be used here, although in a strictly geometric sense, there is no symmetry with respect to the slides, since, although the slides can be positioned opposite each other in a plane of symmetry, they are rotated 180° relative to each other about their longitudinal axis.

[0021] The projection has a break into which a locking element can engage to block movement of the slide.

[0022] The protrusion at the ends of the sled can also be used to trigger position sensors.

[0023] Furthermore, the electric remote drive has a locking element in the form of a prism with an essentially triangular base, movable about a locking pivot axis, in order to prevent simultaneous starting of both slides by engaging the interruption of the projection while simultaneously bearing against the projection of an oppositely mountable slide.

[0024] In a mirror-symmetrical mounting of two electric remote drives, the vertically offset, facing projections of the opposing carriages, in conjunction with the locking element, form a locking mechanism. By engaging the gap of one projection and resting against the other projection, moving one carriage blocks the other. If the locking element is omitted, the locking function is also eliminated.

[0025] Preferably, the electric remote drive has position sensors for determining the switching state by detecting the respective end position of the carriage.

[0026] The position sensors allow the current switching state of the electrical switching device to be detected and further processed in a higher-level control system of the electrical installation.

[0027] Furthermore, the position sensors are arranged in such a way that the projection of the carriage directly activates the corresponding position sensor when the carriage reaches its end position.

[0028] The position sensors can be attached directly to the drive mechanism at the height of the projection - in the case of mirror-symmetrical mounting of two electric remote drives at the height of the respective projection - so that they are actuated by retracting a head-side end of the projection.

[0029] Advantageously, the position sensors are arranged in a mechanically decoupled manner and are actuated by means of a belt tensioning device, which has a belt tensioning guide through which a belt attached to the carriage is guided to the position sensors.

[0030] As an alternative to directly actuating the position sensors via the carriage projection and the associated installation directly on the drive mechanism, the position sensors can also be mechanically decoupled and arranged outside the moving elements of the drive and actuated by means of a belt tensioning device. This positioning of the position sensors prevents the transmission of mechanical vibrations that can occur during switching.

[0031] The belt tensioning device has a belt tensioning guide through which a belt attached to the carriage is guided to the position sensors and switches them.

[0032] Furthermore, the position sensors are designed as optical sensors or as limit switches.

[0033] The position sensors can be implemented as non-contact optical sensors, for example in the form of a fork-type light barrier, whose light beam is interrupted by the projection of the carriage or the belt of the belt tensioning device. Position sensors can also be implemented as contact switches, for example as limit switches.

[0034] Furthermore, the electric remote drive comprises an inner housing part with rocker arm and shift knob mount and an outer housing part which encloses the electromagnets.

[0035] The inner housing part – which, in the case of mirror-symmetrical mounting of two electric remote drives, corresponds to the housing part adjacent to the plane of symmetry – is designed to accommodate the rocker arm and the shift knob. The outer housing part houses the electromagnets.

[0036] The invention further relates to an electric remote drive arrangement with an electric remote drive according to the invention, with an electric switching device and with a vibration-damped base plate with electronic assembly, wherein decoupling springs establish a conductive and mechanically decoupled connection between the electronic assembly and switch terminals of the switching device.

[0037] In this embodiment of the invention, the claimed electric remote drive arrangement thus comprises, in addition to the electric remote drive according to the invention, the electric switching device and a vibration-damped base plate with decoupling springs and an electronic assembly that houses the measuring and control electronics of the electric switching device. The base plate thus forms a printed circuit board supporting the electronic components. An electrically and mechanically decoupled connection is established between the switch terminals attached to the switching device and the electronic assembly located on the vibration-damped base plate via the conductive decoupling springs. This significantly reduces installation effort, particularly wiring work, while simultaneously reducing the susceptibility to errors.

[0038] Preferably, the base plate is mounted with vibration-damping rubber buffers.

[0039] The circuit board, which serves as the base plate, is vibration-damped using rubber buffers. The rubber buffers have internal threads at their ends for screw fastening and are screwed to the base plate and to lateral projections of angle brackets.

[0040] The invention further relates to an electric remote drive unit with a left-hand and a right-hand electric remote drive arrangement according to the invention, which are arranged in a mirror-symmetrical manner to each other and are mounted on angle rails by means of threaded screws leading through receiving bores in the electric remote drives and the electric switching devices.

[0041] In this embodiment of the invention, two mirror-symmetrical electric remote drive assemblies, together with the angle brackets, form a fully assembled remote drive unit, requiring only the external wiring to the power supply system. The electric remote drives and the electrical switching devices are clamped between the angle brackets by means of through-bolts, with the base plate being designed as a single unit serving as a common base plate for the left- and right-hand switching devices. The remote drive unit can be mounted as a single structural unit, for example, on support rails, using the angle brackets.

[0042] Furthermore, the electric remote drive unit has a trough-shaped protective cover, which is attached to the angle rails on the back of the base plate to protect against dangerous touch voltages.

[0043] Due to the mirror-symmetrical arrangement, a large number of components are designed as identical parts, which is advantageous from a manufacturing and economic perspective. This applies particularly to the drive mechanism with its slide, rocker arm, and crank. These components can therefore be used on both the left and right sides.

[0044] Further advantageous design features will become apparent from the following description and the drawings, which illustrate preferred embodiments of the invention by means of examples. They show: Fig. 1: an electric remote drive unit with two mirror-symmetrical electric remote drive arrangements, Fig. 2: a drive mechanism of the remote drive with a view of electromagnets, slides and rocker arms, Fig. 3: the drive mechanism with a detailed view of the rocker arm, Fig. 4: the drive mechanism with a view of the attached crank, Fig. 5: the drive mechanism with locking element, Fig. 6: the drive mechanism with belt tensioning device and Fig. 7: the drive mechanism with belt tensioning device for a mirror-symmetrical electric remote drive arrangement.

[0045] Fig. Figure 1 shows an electric remote drive unit 90 with two mirror-symmetrical electric remote drive arrangements 80.

[0046] The complete electric remote drive unit 90 thus consists of two electric remote drive arrangements 80 with angle rails 55 and can be mounted as a closed assembly unit, for example on (not shown) support rails.

[0047] The respective left- and right-hand mirrored electric remote drive arrangement 80 comprises an electric remote drive 2 and one or more electric switching devices 4, each operable via a switching shaft 5.

[0048] The electric remote drives 2 each have an inner housing part 56 and an outer housing part 58 and are fastened together with the electrical switching units 4 between the angle rails 55 by means of through threaded screws 54.

[0049] The electrical switching units 4 are each equipped with switch terminals 7 for contacting the conductors of a power supply system.

[0050] As protection against dangerous touch voltages on the base plate 50 (circuit board), a trough-shaped protective cover 53 is attached to the angle rails 55 on the back.

[0051] The electric remote drive unit 90 can also be expanded in such a way that, for example, four switching devices 4 are arranged on each side for switching a 4-wire network.

[0052] In the Fig. 2, Fig. 3 and Fig. Figure 4 shows the drive mechanism of the remote drive 2 with a view of electromagnets 6, slide 10, rocker arm 20 and crank 30.

[0053] The rocker arm 20 has a first lever arm 21 ( Fig. 3) which engages in a trough-shaped recess 12 of the slide 10 and is moved about the rocker arm pivot axis 23 when the slide 10 is moved. A second lever arm 22 of the rocker arm 20 has a recess 24 at its end, into which a pin 31 ( Fig. 4) a crank 30 ( Fig. 4) engages and thus drives the crank 30 to a pivoting movement.

[0054] The rocker arm pivot axis 23 has a roof-shaped contour 26 that is axially offset in sections ( Fig. 3) on, at the tip of which a leaf spring 25 presses to fix the switching position (angular positions) in two stable states.

[0055] Four decoupling springs 52 form a conductive and mechanically decoupled connection in pairs opposite each other between the switch terminals 7 of the switching device 4 and an electronic assembly arranged on the base plate 50.

[0056] The base plate 50 is attached to lateral projections of the angle rails 55 by means of rubber buffers 51, the rubber buffers 51 having an internal thread at their head ends for screw fastening.

[0057] Fig. Figure 3 shows the drive mechanism with a detailed view of the rocker arm 20 with first lever arm 21 and second lever arm 22.

[0058] The leaf spring 25 rests on one side of the roof-shaped contour 26 of the rocker arm pivot axis 23 to fix the switching position.

[0059] A shift knob 28 for manual switching is axially mounted on the rocker arm pivot axis 23.

[0060] Fig. Figure 4 shows the drive mechanism with a view of the attached crank 30.

[0061] The crank 30 is axially mounted on the rocker arm 20 and has an arc-shaped elongated hole 33 to allow the crank 30 to be mounted without collision with the rocker arm pivot axis 23.

[0062] By engaging the pin 31 in the recess 24 of the second lever arm 22 of the rocker arm 20, the crank 30 is caused to pivot. This transmits torque to the switching shaft 5 of the electrical switching device 4 ( Fig. 1) The crank 30 has a positive-locking receiving bore 32 in the form of an internal toothing.

[0063] Fig. Figure 5 shows the drive mechanism with locking element 60.

[0064] The slide 10 has a rib-like projection 14 with a gap 15 along one edge on its longitudinal side – in the direction of displacement. The locking element 60, which is movable about a locking pivot axis 62, engages in this gap 15. The locking element 60 has the shape of a prism with a substantially triangular base.

[0065] In the electric remote drive unit 90, due to the mirror-symmetrical position of the electric remote drive arrangements 80, in an end position of one of the slides 10, an edge of the locking element 60 is aligned parallel to the web-like projection 14 of this slide 10 - thus enabling its displacement - whereas the other slide 10 is blocked by the locking element 60 engaging in the interruption 15 of the projection 14.

[0066] The switching state of the electrical switching device 4 is determined by detecting the respective end position of the slide 10. For this purpose, position sensors 40 are arranged opposite each other on a circuit board 41 leading perpendicularly from the drive mechanism into the base plate 50, such that a head-side end of the projection 14 directly actuates the position sensors 40 when the slide 10 reaches its end position. Preferably, the position sensors 40 are designed as slotted optical sensors.

[0067] Fig. Figure 6 shows the drive mechanism with belt tension device 72, 74 for actuating the position sensors 40.

[0068] The belt tensioning device 72, 74 consists of a belt tensioning guide 72, which is provided twice for each of the two carriages 10 and is routed in an arc from the respective end position of the carriage 10 at the level of the projection 14 to the base plate 50. A belt 74 attached to the carriage 10 is guided through the belt tensioning guide 72 to the position sensors 40 ( Fig. 7) guided, which are preferably designed as optical sensors in the form of fork light barriers and which are triggered by the pulling and pushing movement of the belt 74. The belt tensioning device 72, 74 thus enables the position sensors 40 ( Fig. 7), as an alternative to direct actuation by means of the projections 14, they can be positioned mechanically decoupled outside the moving elements of the drive.

[0069] Fig. Figure 7 shows the drive mechanism with belt tension device 72, 74 for a mirror-symmetrical electric remote drive arrangement 80.

[0070] Starting from the end positions of the carriages 10 at the height of the projections 14, the belt tension guides 72 extend in an arc towards the base plate 50, where the belt 74 guided in the belt tension device 72 actuates the corresponding fork light barrier 40.

[0071] The receiving bores 57 (in the electric remote drives 2 and the electric switching devices 4) can be seen. Fig. 1), through which the threaded screws 54 ( Fig. 1) for clamping the two mirror-symmetrically arranged electric remote drive assemblies 80 ( Fig. 1) between the angle rails 55 ( Fig. 1) be conducted.

Claims

[1] Electric remote drive (2) for actuating an electric switching device (4) with rotary force reception via a switching shaft (5), with two independently controllable actuators (6) designed as electromagnets (6) acting oppositely on a slidably mounted carriage (10), characterized by , that the slide (10) has a trough-shaped recess (12) for carrying a first lever arm (21) of a rocker arm (20) mounted about a rocker arm pivot axis (23), the second lever arm (22) of which has a recess (24) at its end, into which a pin (31) of a crank (30) engages, which can be positively connected (32) to the shift shaft (5) and has an arc-shaped elongated hole (33) through which the rocker arm pivot axis (23) runs, wherein the rocker arm pivot axis (23) is axially offset circumferentially as a section-wise roof-shaped contour (26), on which a leaf spring (25) rests for fixing a shift position. [2] Electric remote drive (2) according to claim 1, characterized by a shift knob (28) that can be axially attached to the rocker arm pivot axis (23) for manual switching. [3] Electric remote drive (2) according to claim 1 or 2, characterized by, that the sled (10) has a rib-like projection (14) with a break (15) along one edge on its longitudinal side. [4] Electric remote drive (2) according to one of claims 1 to 3, characterized by a locking element (60) movable about a locking pivot axis (62) in the form of a prism with an essentially triangular base, in order to prevent the simultaneous starting of both slides (10) by engaging the interruption (15) of the projection (14) while simultaneously bearing against the projection (14) of an oppositely mountable slide (10). [5] Electric remote drive (2) according to any one of claims 1 to 4, characterized by Position sensors (40) for determining the switching state by detecting the respective end position of the slide (10). [6] Electric remote drive (2) according to claim 5, characterized by, that the position sensors (40) are arranged such that the projection (14) of the slide (10) directly actuates the corresponding position sensor (40) when the slide (10) reaches its end position. [7] Electric remote drive (2) according to claim 5 characterized by , that the position sensors (40) are arranged in a mechanically decoupled manner and are actuated by means of a belt tension device (72, 74) which has a belt tension guide (72) through which a belt (74) attached to the carriage (10) is guided to the position sensors (40). [8] Electric remote drive (2) according to any one of claims 5 to 7, characterized by that the position sensors (40) are designed as optical sensors (40) or as limit switches. [9] Electric remote drive (2) according to any one of claims 1 to 8, characterized by , an inner housing part (56) with rocker arm and shift knob receptacle and an outer housing part (58) which encloses the electromagnets (6). [10] Electric remote drive arrangement (80) comprising an electric remote drive (2) according to claim 9, an electric switching device (4) and a vibration-damped base plate (50) with electronic assembly, wherein decoupling springs (52) provide a conductive and mechanically decoupled connection between the electronic assembly and switch terminals (7) of the switching device (4). [11] Electric remote drive arrangement (80) according to claim 10, characterized by , that the base plate (50) is mounted with rubber buffers (51) in a vibration-damped manner. [12] Electric remote drive unit (90) with a left-hand and a right-hand electric remote drive arrangement (80) each designed according to one of claims 10 and 11, which are arranged symmetrically to each other and are mounted on angle rails (55) by means of threaded screws (54) leading through receiving bores (57) in the electric remote drives (2) and the electric switching devices (4). [13] Electric remote drive unit (90) according to claim 12, characterized by a trough-shaped protective cover (53) which is attached to the angle rails (55) on the back of the base plate (50) to provide protection against hazardous contact voltages.

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