WO2020211992A1

WO2020211992A1 - Triggering apparatus for an electrical switch device

Info

Publication number: WO2020211992A1
Application number: PCT/EP2020/054068
Authority: WO
Inventors: Georg Bachmaier; Matthias Gerlich; Gunnar Lutzke; Christian Schacherer; Florian SCHIRRMACHER; Christian Wallner; Wolfgang Zöls
Original assignee: Siemens Aktiengesellschaft
Priority date: 2019-04-17
Filing date: 2020-02-17
Publication date: 2020-10-22
Also published as: DE102019205576B4; DE102019205576A1

Abstract

The invention relates to a triggering apparatus (1) for an electrical switch device (3), comprising - an actuator (A), - a hydraulic transmission unit (H) connected mechanically to the actuator (A) in series, - a cable system (M), which is connected mechanically to the hydraulic transmission unit (H) in series and acts as a mechanical transmission unit for the hydraulic transmission unit (H), - and a triggering body (T), which can be moved by means of the cable system (M) for triggering a switching process in the switch device (3). The invention further relates to an electrical switch device (3) having a triggering apparatus (1) of this kind.

Description

description

Tripping device for an electrical switching device

The present invention relates to a triggering device for an electrical switching device, comprising an actuator and a movable trigger body for triggering a

Switching process in the switching device. The invention also relates to an electrical switching device with such a triggering device.

According to the state of the art, different types of switching devices are used in electrical energy networks to protect the network components and the devices, machines and systems to be supplied with energy. This applies to low-voltage, medium-voltage and high-voltage networks, and in each case to both DC and AC networks. These switching devices often have to be designed for very fast switching processes in which two electrical switching contacts have to be either opened (that is, moved apart) or closed (that is, brought into contact with one another) very quickly. In order to enable these rapid switching movements, pre-tensioned drive springs are often present in known switching devices, which are locked by a positive locking. This form-fitting locking is often also referred to as a latch. This lock must be released to initiate the corresponding switching movement. For this purpose, according to the prior art, triggering devices with electromagnetic actuators are typically used. Such an electromagnetic actuator can be, for example, a magnetic coil which can exert a magnetic force on a release tappet by applying a supply voltage and the associated current flow in the magnetic coil. Such a release device with an electromagnetic tables coil is described for example in DE 102017207624 A1. An essential requirement for such a Auslösevorrich device is, on the one hand, a relatively high release speed, with the total release time from the electrical activation of the actuator to the opening or closing of the switching contacts being only a few milliseconds. At the same time, such a release device typically has to achieve a mechanical stroke (i.e. a deflection) of several millimeters with a load force of several tens of Newtons in order to be able to release the locking mechanism of the drive unit. This results in a required switching energy of a few 10 mJ to a few 100 mJ. The short switching times of a few milliseconds result in powers of several tens of watts, and power peaks of around 1000 watts or even more can occur with the known electromagnetic tripping devices. For example, with such a conventional release device, a peak power of 1200 W is typical for quick release with an electromagnetic coil as the actuator.

In many switchgear systems, there is also a spatial separation between the protective relay (and thus the electrical energy supply for the trip unit) and the trip unit itself. In large overall systems, especially in high-voltage applications in the range of 52 kV or more, there is often a spatial concentration of all control and supply components on the one hand (for example in an air-conditioned environment) and the switching devices controlled with them on the other. Such a spatial separation can, for example, be due to the high requirements for electrical insulation in a free-field system. With such an arrangement, the distance between the Energiever supply and the release device can easily be several 100 m. Accordingly, there are very long lengths for the electrical lines between the power supply and the release device. The voltage drop over such a long line caused by the electrical losses must not lead to an unauthorized drop in the voltage at the trip unit. If the tension is due to high Line impedance is reduced too much, the tripping speed that can be achieved with an electromagnetic tripping unit is in turn reduced. In order to reduce the line impedance, lines with a very large cross-section are often used. However, this is associated with relatively high costs.

In addition, the switching energy must be available for all releases and it must be stored in an energy store such as be kept in a battery. In larger substations or systems, several 10 such triggers can be installed, which leads to very large energy storage devices with corresponding space requirements, which is also associated with high costs.

Overall, there is a need for a triggering device for an electrical switching device which meets the requirements for speed, stroke and force described above and at the same time achieves the lowest possible value for the electrical peak power.

The object of the invention is therefore to specify a triggering device for an electrical switching device which overcomes the disadvantages mentioned. In particular, a triggering device is to be made available which can be operated with a reduced peak power compared to the described prior art. For this purpose, the mechanical energy required for triggering the switch should be converted as efficiently as possible from the electrical energy supply. The power consumption should also be distributed as evenly as possible over the duration of the release process in order to keep the peak power low. Another object is to specify an electrical switching device with such a release device.

These objects are achieved by the release device described in claim 1 and the electric switching device described in claim 13. The triggering device according to the invention is designed as a Auslösevor direction for an electrical switching device.

It comprises an actuator, a hydraulic transmission unit that is mechanically connected in series with the actuator and a cable system that is mechanically connected in series with the hydraulic transmission unit. The cable system acts as a mechanical transmission unit for the hydraulic transmission unit. Furthermore, the triggering device comprises a triggering body that can be moved by means of the cable system for triggering a switching process in the switching device.

The term "mechanically connected in series" is to be understood here generally as meaning that the actuator is connected to a drive side of the hydraulic transmission unit in a force-transmitting manner. The cable system should therefore in particular with the side opposite the actuator (i.e. the output side) of the hydraulic transmission unit The hydraulic transmission unit thus forms the first transmission stage after the actuator, and the cable system forms a downstream second transmission stage. These two stages result in an overall transmission ratio, which is made up of the individual transmission ratios of the hydraulic transmission unit and the cable system The cable system in turn is mechanically coupled to the hydraulic transmission unit on its drive side and connected to the movable release body on its output side Generally speaking, a translational body or a rotary body. It is only essential in connection with the invention that this release body can be used to trigger a switching process in the switching device. For example, this release body can perform a translation movement through which a downstream Ver latching of the switching device is released. The described switching process in the switching device can generally be either opening or closing of the switch. The cable system is, in particular, a mechanical transmission system with a cable as the motion-transmitting component. The drive side is in the area of a first cable end and the output side is in the area of a second.

A major advantage of the Auslösevor device according to the invention is that the arrangement with two translation units connected in series makes it possible to achieve a relatively large stroke of the release body, even if the actuator used itself can only generate a comparatively low stroke. In this way, especially when using a solid-state actuator with a small input stroke, an output stroke of in particular several millimeters that is necessary for triggering the switch can be generated.

Another advantage can be seen in the fact that this comparatively large stroke can also be achieved with short triggering times of, in particular, only a few milliseconds.

This is mainly due to the high rigidity of the entire transmission system.

On the one hand, the hydraulic transmission unit can be designed relatively easily with a high degree of rigidity. This can be achieved in particular through the use of a comparatively low working volume of the hydraulic fluid, through the least possible leakage, through chamber walls with little lateral deformability and / or through the use of pistons as lifting elements. In general, hydraulic transmission units are particularly suitable for a stroke transmission with high dynamics. In the present context, “high dynamics” of the transmission unit should generally be understood to mean a quick response behavior over time. In other words, “high dynamics” should mean that a short, fast movement on the drive side with a small time offset and less time Expansion is translated into a correspondingly short, fast movement on the output side.

In addition to the hydraulic transmission unit, the cable system connected in series can also be implemented relatively easily with high mechanical rigidity and correspondingly high dynamics. Especially when choosing rope materials with low elasticity and high tensile strength, a high stiffness can be achieved relatively easily with a relatively low mass of the moving parts in such a rope system.

Another advantage is that the large stroke and high dynamics can be achieved with a comparatively low peak performance. This is made possible in particular by the fact that both the generation of the stroke in the actuator and the stroke ratio in the two ratio stages can take place in a comparatively energy-efficient manner. In particular, when using a solid-state actuator, relatively low losses occur when generating the primary stroke. The hydraulic translation unit can also be operated easily with low energy losses, especially if the working volume and thus the moving mass of the hydraulic fluid can be kept low. The cable system can also easily be operated with low energy losses, especially if the cable has a low elastic deformability.

In summary, with the triggering device according to the invention, the requirements for the height of the stroke and the triggering speed for triggering a switching process can be implemented, with an energy-efficient implementation taking place at the same time. This can in particular be an efficient conversion of electrical energy used to operate the actuator into mechanical movement energy of the release body. In addition, the implementation can also be performed efficiently. The electrical switching device according to the invention has a triggering device according to the invention. The advantages of the switching device according to the invention result analogously to the advantages of the triggering device according to the invention described above.

Advantageous refinements and developments of the invention emerge from the claims dependent on claims 1 and 13 and the following description. The described configurations of the release device and the electrical switching device can generally be advantageously combined with one another.

Thus, according to an advantageous embodiment, the rope system can be designed as a pulley system. Such a Fla schenzugsystem can in particular have a motion-transmitting rope and a plurality of pulleys. One advantage of this embodiment is that in this way a desired path transmission ratio can be set relatively easily. In particular, the transmission ratio can be influenced by the choice of the number of pulleys. At the same time, by choosing a rope with low elasticity and high tensile strength, a mechanical transmission unit with high rigidity and low mass can be made available.

In such a pulley system, the number n of swivel castors can advantageously be at least 2, particularly advantageously at least 4, and in particular between 2 and 20. In particular, these roles can be combined in groups to form individual blocks, with the roles of a common block each being fixed to a common support body. In particular, a total of two such opposite blocks can be provided, each with a plurality of roles. The angle of rotation of the rope over the rollers of the two blocks can advantageously be around 180 °. In other words, then essentially half of each roller is rotated by the rope. In addition to the two blocks of pulleys described, the pulley system can also have a further lateral swivel pulley in which the angle of rotation of the rope is variable depending on the set position. This variable angle of rotation can in particular be in the range between 90 ° and 180 °. The variation in the rotation angle is caused by the movement of an output body of the cable system that is firmly connected to the cable, that is, for example, by the movement of a ram. It can therefore in particular be a side pulley on the output side.

In general, and regardless of the exact embodiment and number of pulleys, the pulley system can basically be a factor pulley block, a power pulley block and / or a differential pulley block.

Generally advantageous, the cable system can have a transmission ratio of less than 1. With this transmission ratio, a movement of a drive body of the cable system is transferred to a movement of an output body of the cable system. With a transmission ratio below half of 1, the stroke on the output side is greater than the stroke on the drive side. The transmission ratio mentioned here should therefore generally be understood to mean the ratio of the stroke on the drive side to the stroke on the output side of the respective transmission device. As the stroke increases, this transmission ratio is correspondingly smaller than 1. The cable system particularly preferably has a transmission ratio of 1: 2 or less. With a transmission ratio below 1: 2, an even higher stroke increase than twice the stroke is obtained. In other words, the stroke on the output side is at least doubled in relation to the stroke on the drive side of the cable system. As a result, a significant (further) stroke translation is achieved in the second translation stage of the release device. Thus, for the release device As a whole, a sufficiently high stroke of the release body can be achieved, which is sufficient to trigger the switching process. This can also be achieved in particular for actuators with a comparatively small primary stroke.

With a cable system, a transmission ratio in a generally advantageous range between 1: 2 and 1:50 can advantageously be easily achieved. A transmission ratio in an advantageous range between 1: 2 and 1:20 can be realized with a comparatively low expenditure on equipment.

Generally advantageous and independent of the exact design of the cable system, the hydraulic transmission unit and the cable system together can have a total transmission of at most 1: 4 in the release device. In other words, both transmission stages can work together in such a way that a stroke that is at least four times greater than the stroke of the actuator is achieved for the release body. This overall transmission ratio can particularly preferably be at most 1:10, in particular at most 1:20, further particularly preferably at most 1:50 and in particular even at most 1: 100. Such high overall translations make it possible to achieve a sufficiently high stroke of the release body even with primary actuators with only a very small stroke (such as piezo actuators).

Thus, the release body can generally advantageously have a stroke of at least 2 mm and in particular at least 3 mm. In other words, the release body can be moved by at least this stroke in the translation stages through the primary stroke of the actuator and the stroke-multiplying effect. A stroke of the release body in this area is particularly suitable to release a latch in a switching device and thus trigger the desired switching process. The stroke of the release body can, for example, be in a range between 2 mm and 6 mm. In general, the release body can advantageously be an elongate shaped plunger. Such a plunger can in particular be movably supported with essentially only one translational degree of freedom. In particular, a sliding bushing can be used for such a one-dimensionally movable mounting. In other words, the plunger then acts as a translation body, the translational movement of which can trigger the switching process. The movement of the rope is then transferred to a one-dimensional movement of this translati onskörpers.

As an alternative to the embodiment with a translation body, the release body can also be a rotation body. In other words, the translational movement can also be converted into a rotary movement of a rotary body by the translation unit, whereby a locking device of a switching device is then released in particular. Such an implementation of a rotary movement can take place, for example, through a connection with a roller.

According to an advantageous embodiment of the hydraulic transmission unit, it can have a drive element and an output element. It can in particular be designed to transmit a movement of the drive element with a transmission ratio of less than 1 to the output element. In other words, the hydraulic translation unit should also increase the stroke. The transmission ratio of the hydraulic unit can particularly advantageously be at most 1: 2 and in particular 1:10, very particularly advantageously even at most 1:20 or even at most 1:50. In this way, a corresponding increase in the stroke can be achieved in the first stage of the entire release device, this stroke of the hydraulic unit then being further increased again by the advantageous transmission ratio of the cable system described. According to a generally advantageous embodiment of the hydraulic transmission unit, it can be filled with a hydraulic fluid. In particular, it has a first and a second chamber, which are hydraulically connected to one another and of which one is designed as a drive chamber and the other is designed as an output chamber. In this case, the drive chamber and output chamber can generally either be fluidically connected by a line or also merge directly into one another as partial areas of a higher-level chamber volume. This basic structure of the hydraulic translation unit is known for example from the laid-open documents DE 102016213654 A1 and DE 102013219759 A1.

According to a particularly preferred embodiment of the hydraulic transmission unit, a piston can be arranged movably along a piston axis at least in the first chamber (as either in the drive chamber and / or in the drive chamber). This piston can separate the first chamber into a volume-variable working chamber and a rear chamber, the rear chamber being at least partially limited by a bellows element with a variable axial length. In other words, the hydraulic unit is neither a pure piston system nor a pure bellows system, but a mixed piston-bellows system in which both types of limiting elements are present next to one another in at least one of the two chambers. In particular, both chambers (drive chamber and output chamber) can even be implemented as such a mixed piston-bellows system. Particularly advantageous embodiments of such a mixed piston-bellows system are described in more detail in the international application filed by Siemens AG and MetisMotion GmbH on the same filing date with the title "Hydraulic translation unit for an actuator device", which is therefore included in the disclosure content of the present Alternatively, the hydraulic transmission unit can also be implemented as a pure piston system or as a pure bellows system, as they are also described in more detail in the above-cited application filed in parallel.

Generally advantageous and independent of the precise design of the hydraulic transmission unit, it can have a storage chamber for the hydraulic fluid. Such a storage chamber can in particular be fluidically connected or ver connectable to the rear chamber described above. It can be useful in particular when a movement of the piston for the rear chamber is not completely volume-neutral. A small change in volume of the rear chamber can thus be advantageously compensated for by a fluid coupling to the storage chamber. Alternatively or additionally, a coupling to a storage chamber can also be useful in order to compensate for a change in the volume of hydraulic fluid caused by a change in temperature. In a particularly preferred variant of this embodiment, the storage chamber can be pressurized. Such a possibility of applying pressure can be implemented, for example, by an additional bellows element or a piston in the area of the storage chamber. In this way, the storage chamber can be subjected to a pressure which, for example, can be higher or lower than the pressure in the rear side chamber fluidically coupled to the storage chamber. For example, the entire hydraulic system can be preloaded to a desired output pressure by means of an actuating element in the area of the storage chamber, whereby a desired starting position of an output body on the output side can be set. The starting position of the output body that is established in each case depends on the rigidity of the bellows elements used and the tension forces acting on the actuating body and the output body.

In general, the hydraulic transmission unit can be filled with a hydraulic fluid. In this embodiment, the hydraulic fluid is already part of the translation unit. In order to implement the invention, however, it is basically sufficient if the transmission unit has a chamber system suitable for filling with the hydraulic fluid. A suitable hydraulic fluid is, for example, a silicone oil, a glycol or a liquid metal. When the transmission unit is filled with the hydraulic fluid, it is found both in the drive chamber and in the output chamber (and, if necessary, in the working chamber as well as in the rear chamber) and additionally in one or more optionally available connecting lines and / or Pantries. In general, the drive chamber and the output chamber can either be fluidically connected by a line or also merge directly into one another as subregions of a higher-level chamber volume.

Generally advantageously, the total working volume of the hydraulic transmission unit can be 1 ml or less. In particular, the working volume can be in the range below 0.5 ml or even below 0.1 ml and in particular between 0.01 ml and 0.5 ml or between 0.01 ml and 0.1 ml. With such a low working volume, a translation unit with high rigidity and / or high dynamics can be implemented particularly easily.

Generally advantageously, the release device can have at least two subsystems that are mechanically connected in parallel. Each of the subsystems can have an actuator, a hydraulic transmission unit connected mechanically in series with the actuator and a cable system mechanically connected in series with the hydraulic transmission unit. In particular, the two cable systems can be mechanically coupled to a common, higher-level release body, so that simultaneous control of the two actuators leads to a joint movement of the higher-level release body by means of the two hydraulic transmission units and the two cable systems. Such a doubling of the actuators, the hydraulic translation units and the cable systems and their mechanical parallel connection can in particular cause a correspondingly higher energy to be available for the movement of the release body. Particularly advantageous is a symmetrical, similar design of the two subsystems, which means that the available energy can be doubled. In particular, with a mirror-symmetrical arrangement of the sub-systems, an approximately doubling of the energy can advantageously be achieved with a straight, fluid movement of the Auslösekör pers, since canting is advantageously avoided. In general, the two subsystems can be arranged in a common housing in a particularly advantageous manner.

According to a preferred embodiment, the actuator is a solid-state actuator. With such a solid-state actuator, the described advantages of the inventive design of the downstream transmission units come into play particularly effectively, since in particular the stroke of a solid-state actuator is severely limited in practice and high stiffnesses depending on the actuator type are advantageous for power transmission. A solid-state actuator typically has a high natural frequency and thus advantageously high dynamics.

According to a particularly preferred variant, the Festkör peraktor is a piezo actuator. Piezo actuators have proven to be particularly promising primary actuators in the past. With them a particularly precise movement can be achieved. Their main disadvantage, namely their low mechanical stroke, can be compensated for by the following translation units, as described. Even with a corresponding reduction in the force through the translation stages, the force for triggering the switching process is still sufficient.

The piezo actuator of the actuator device is particularly preferably designed as a piezo stack actuator. A piezo stack actuator is a series circuit which is basically known from the prior art and consists of several individual piezo elements, which are arranged as a layer stack. Such a stack actuator is particularly advantageous in order to achieve a higher movement amplitude with the piezo actuator than would be possible with a single piezo element.

However, the invention is not limited to a piezo actuator as a solid body actuator. Many of the known advantages and disadvantages of piezo actuators also apply to other types of solid-state actuators. For them, too, a comparatively small output stroke can be increased by the following translation units. According to a preferred embodiment variant, said solid-state actuator is, for example, a magnetostrictive actuator or an electrostrictive actuator. Alternatively, the solid-state actuator can also be a shape memory actuator.

According to an advantageous embodiment of the electrical switching device, it can be designed as a switching device for a high-voltage network. Alternatively or additionally, it can also be designed as a switching device for a medium voltage network. Alternatively or additionally, it can also be designed as a switching device for a low-voltage network. Regardless of the voltage range provided, the switching device can generally advantageously be provided as a switching device for an alternating current network. Alternatively, it can also be advantageously provided as a switching device for a direct current network.

According to a generally advantageous embodiment, the electrical switching device can have a stationary first switching contact and a second switching contact that is movable relative to this. In this case, the triggering device can in particular be designed to trigger the movement of the second switching contact. The stroke typically required for this can be achieved in an effective manner by the inventive design of the triggering device. Particularly advantageously, the electrical switching device can additionally have a biasing element which is designed to bias the second switching contact relative to the first switching contact. In particular, the switching device can furthermore have a locking device which is designed to lock the prestressing element in such a prestressed state. The release device can then be appropriately designed to solve the Arretierungsvorrich device.

The described biasing of the biasing element can in principle be either a biasing for an opening movement or a biasing for a closing movement of the switching contacts. By releasing the locking device, either the opening movement or the closing movement is triggered accordingly. For example, the release device according to the invention can be used as an alternative to the electromagnetic Spu described in DE 102017207624 A1. It can therefore be used in the switching device described there in order to release the latching of the crown gears provided with teeth.

The invention is described below on the basis of a few preferred exemplary embodiments with reference to the attached drawings, in which:

Figure 1 shows a schematic diagram of an electrical switching device with a triggering device according to a first example of the invention,

Figure 2 is a schematic representation of a hydraulic

Translation unit shows

Figure 3 is a schematic representation of a cable system

shows,

Figure 4 is a schematic representation of an alternative

Rope system shows

Figure 5 shows the cable system of Figure 4 in a different

Position shows Figure 6 shows a schematic diagram of a triggering device according to a second example of the invention,

Figure 7 is a schematic representation of the two hydrauli

between translation units of Figure 6 shows,

Figure 8 shows a schematic representation of the two cable systems of Figure 6,

Figure 9 is a schematic overall view of the hydraulic

Translation units and the cable systems of Figure 6 shows,

Figure 10 shows the time course of the tension and the strokes as

Shows the function of time in such a system and FIG. 11 shows the course of electrical voltage over time,

Shows electricity, power and energy as a function of time.

Identical or functionally identical elements are provided with the same reference symbols in the figures.

In Figure 1 is a schematic diagram of an electrical switching device 3 with a triggering device 1 according to a first embodiment of the invention shows GE. The connections between the boxes each represent a mechanical coupling of the individual elements. The release device 1 comprises an actuator A, a hydraulic transmission unit H connected mechanically in series with the actuator and a cable system M mechanically connected in series with the hydraulic transmission unit H. This cable system M acts as a mechanical transmission unit, wel che as the second transmission stage of the hydraulic Translation unit H is connected downstream. By means of the cable system M, a release body T can be moved, with which the actual switching process in the switching device 3 can be triggered. The actual switching of the switching device consists in opening or closing two switching contacts S1 and S2 (as indicated by the opposite arrows). The first of these switching contacts S1 is fixed net, and the second switching contact S2 is arranged movable relative to this.

To trigger the switching process, the release body T acts on a locking device F. This locking device F can, for example, as indicated by the pictogram, have two elements that are interlocked by a form fit, in which the form fit prevents their relative movement to one another. Also as part of the switching device 3, a biasing element V is provided here, by means of which the second switching contact S2 is biased with respect to an opening movement or a closing movement. By releasing the form fit in the locking device F, the switch can be opened or closed quickly with the aid of this bias. The actual triggering device 1 is used here to release the lock within the locking device F approximately. A stroke of several mm, for example, may be necessary for this. The release device 1 is designed to achieve this stroke with the aid of two transmission units connected in series, namely the hydraulic transmission unit H and the cable system M as a mechanical transmission unit.

The primary stroke within the triggering device 1 is generated by an actuator A, which can be a piezo actuator, for example. The stroke of this actuator A is denoted by SA.

This is also the stroke that acts on the drive side Ha of the following hydraulic translation unit H. The transmission ratio of this hydraulic transmission unit is selected in the present example so that the stroke on the output side Hb of the hydraulic transmission unit H is enlarged compared to the primary stroke. The stroke on the output side is labeled SH. This is also the stroke that acts on the drive side Ma of the following cable system M. The enlargement of the strokes is illustrated here by an arrow that becomes larger and larger, although this enlargement is not true to scale. Also the direction of the arrows is to be understood only as an example. In general, the release can in principle take place either by a pulling movement or by a pushing movement on the locking device. A further increase in the stroke is also achieved through the transmission ratio of the following cable system M. The stroke SM on the output side Mb of the cable system M is increased by a further factor here. This output stroke SM is at the same time that stroke which is reached with the release body T of the release device 1.

In the following figures, the mode of operation of the two translation units connected one after the other will now be explained in more detail. Thus, FIG. 2 shows a schematic representation of a hydraulic transmission unit H, such as can be used, for example, in the exemplary embodiment in FIG. This hydraulic translation unit H is connected in series with actuator A. The stroke SA from the drive side Ha is translated into a stroke SH on the output side Hb through the hydraulically coupled interaction of two pistons 13a and 13b. The transmission ratio is ideally determined by the ratio of the hydraulic surfaces of the two associated piston bodies. The first working chamber 15a forms a portion of the drive chamber 11a that can be varied by the piston movement, and the second working chamber 15b forms a portion of the output chamber 11b that can be varied by the piston movement there. The two working chambers 15a and 15b are fluidically coupled by a hydraulic line 16. The rear volumes of the two chambers 11a and 11b are encapsulated here. In other words, each of the two chambers 11a and 11b is separated by the piston into a working chamber 15a or 15b and a rear chamber 17a or 17b. The two rear chambers are each encapsulated fluidically from the external environment. They are each at least partially limited by a bellows element 19a or 19b of variable axial length. In the case shown, part of the side wall of the respective rear chamber is formed by such a bellows. This The bellows makes it possible for the rear chamber to be encapsulated and for volume compensation to take place in spite of the movement of the respective piston. In the example of FIG. 2, both the drive chamber 11a and the drive chamber 11b are realized with such a flexibly encapsulated rear chamber. Both rear chambers are fluidically coupled to a storage chamber 41 for the hydraulic fluid 7 via a line 37. This storage chamber 41 is laterally bounded by a bellows element 43. A cover plate 45 can be used to apply pressure to the storage chamber by means of a preset stroke SR. Via the drive body 21b (which here represents the piston pin of the Abtriebskam mer), the increased stroke SH corresponding to the transmission ratio can be transferred to the subsequent cable system. The more precise operation and other advantageous embodiments of such a combined piston-bellows system are described in more detail in the above-mentioned parallel filed international application entitled "Hydraulic translation unit for an actuator device".

FIG. 3 shows a schematic representation of a cable system M, such as can be used, for example, in the release device of FIG. On the drive side of this cable system there is a drive body 103. This drive body 103 can be moved with the stroke SH, which has already been enlarged by the hydraulic unit. This stroke SH is now translated by the downstream cable system M to an even further enlarged SM on the output side of the cable system. For this purpose, the cable system M is designed as a pulley system with a movement-transmitting cable 101 and a plurality of deflection pulleys 107. As an example, four pulleys are shown in the cable system of FIG. However, this number can be significantly larger in a real system in order to achieve a greater magnification. One end of the motion-transmitting cable is connected to the drive body 103. The opposite end of the rope is connected to the output body 109. The output body 109 is here in turn firmly connected to the actual release body T. This release body T is implemented here as a translation body (in particular as a plunger), and its movement is used to release the locking device F, as already described in connection with FIG. The translation body T can be stored in a sliding bushing, not shown in detail here, in such a way that it is essentially only one-dimensionally movable in the direction of the arrow SM.

The four pulleys produce a stroke increased by a factor of 4 in the area of the Abtriebskör 109, ie SM = 4-SH. However, this factor is only intended to illustrate in principle how a certain desired transmission ratio can be achieved by choosing the number of deflection pulleys in a factor block and tackle, namely a ratio of 1: 4 here. The pulleys 107 are grouped together to form two blocks, which are sometimes referred to as scissors of a pulley block. A first block consists of the two rollers connected to the drive body 103. The second block consists of the two rollers connected to the fixing body 105. Drive body 103 and fixing body 105 thus form the two essential support bodies for the blocks of the pulley system.

In Figure 4, a schematic representation of an alternative embodiment for the cable system M is shown. The mode of operation of this alternative cable system is basically similar to that in the example in FIG. 3. In contrast to this, however, an additional lateral deflection pulley 108 is provided here. In contrast to the pulleys 107 already described, the rope rotates this role not with a rotation angle of 180 °, but with a smaller Umlaufwin angle ß, which is between 90 ° and 180 ° here. The additional lateral deflection roller 108, on the one hand, facilitates the transmission of the movement to the only linearly movable release body (or translation body) T. On the other hand, the achievable increase in stroke can be increased even further. The influence on the transmission ratio becomes clear from FIG. 5, which shows the cable system of FIG. 4 in a different setting position. In comparison to the position in FIG. 4, the drive body 103 is offset upwards by a certain stroke SH. In the area in front of the pulley 108 on the drive side, this leads to a stroke of the rope 103, which results as As = 4-SH. In the area after the lateral pulley 108, this change has the following effect:

The length of the rope between the lateral deflection roller 108 and the translation body T had a length 1_0 in the position of FIG. The length of this section is reduced to the value 1_1 = 1_0 - As due to the lift of the rope As = 4-SH in front of the lateral deflection pulley. The angle enclosed between the cable 101 and the translational body T changes from a_0 to a_l. The vertical distance between the lateral deflection roller and the translation body (i.e. the height of the triangle formed) changes from h_0 to h_l, while the horizontal distance d remains constant due to the only one-dimensionally movable mounting of the translation body T. The difference in height Ah = h_l - h_0 thus corresponds to the one-dimensional path length of the translational body and thus the stroke SM. On the basis of the Phythagoras theorem, this height difference can be calculated using the following equation:

SM = Ah = h_0 - sqrt ((1_0 - As) ^L 2 - d ^A 2).

Figure 6 shows a schematic diagram of a tripping device 1 according to a second example of the invention. This triggering device can be integrated in a higher-level switching device 3, not shown here, similar to the example in FIG. 1. In contrast to the previous example, the triggering device 1 is composed of two mechanically parallel subsystems 61 and 62. Each of the two subsystems has an actuator A1 or A2, one for the respective actuator mechanically Hydraulic transmission unit Hl or H2 connected in series and a cable system Ml or M2 connected mechanically in series with the respective hydraulic transmission unit. The two cable systems Ml and M2 are mechanically coupled to a common higher-level release body T. This has the effect that a simultaneous activation of the two actuators A1 and A2 leads to a jointly effected movement of the higher-order release body T. In comparison to the embodiment of FIG. 1 with only one such sub-system, the mechanical energy for moving the release body can be roughly doubled.

The following figures show examples of how particularly advantageous, symmetrical designs of the hydraulic units Hl and H2 and the cable systems Ml and M2 of these two subsystems can look. Thus, FIG. 7 shows a schematic representation of the two hydraulic transmission units Hl and H2, as they can be used in particular in the example of FIG. So here two actuators A1 and A2 are each mechanically connected in series with an associated hydraulic transmission unit Hl or H2. The individual hydraulic transmission units are each configured analogously to the example of FIG. 2 and arranged symmetrically next to one another in a butterfly-like configuration. In the example shown, the individual hydraulic translation units Hl and H2 are not fluidically coupled to one another. Alternatively, however, they could in principle also be fluidically coupled, for example by coupling the two storage chambers 41 or by designing with a common storage chamber. The two hydraulic transmission units are mechanically connected in parallel here. The two output bodies 21b are designed in such a way that by simultaneous and rectified control of the two actuators, a rectified stroke SH is generated at the two output bodies 21b. The two mechanically parallel hydraulic translation units Hl and H2 can also be used as a higher-level hydraulic translation unit H with two inputs and two outputs can be seen.

FIG. 8 shows a schematic representation of the two cable systems M1 and M2, as they can be used in particular in the example of FIG. These two cable systems M1 and M2 can in particular be coupled to the output bodies 21b of the two hydraulic units in FIG. 7 via their two drive bodies 103. The two cable systems M1 and M2 are each designed in a manner similar to that in the example of FIGS. 4 and 5. In contrast to this, here two such cable systems are coupled with their cable ends on the output side to a common higher-level translation body T ge. The arrangement of the two cable systems is mirror-symmetrical. They are arranged back to back like a butterfly, so that the two ropes 101 converge symmetrically on the translation body T via the two opposite lateral deflection pulleys 108. This butterfly-like configuration allows an even, tilt-free transmission of the movement to the jointly moving translation body T. Here, too, the two mechanically parallel cable systems Ml and M2 can be viewed as a higher-level cable system M with two inputs and one coupled output. For such a higher-level cable system, a common, continuous cable can also be used, which is used jointly by the rollers of the two sub-systems M1 and M2. The drive body 103 can also be implemented as a jointly used continuous plate.

Figure 9 shows a schematic overall view of the two hydraulic translation units Hl and H2 and the two cable systems Ml and M2 from the embodiment of Figure 6. In particular, the two hydraulic translation units Hl and H2 of Figure 7 in an overall symmetrical arrangement with the two cable systems Ml and M2 of Figure 8 have been joined together. The two rope ends can be connected to one another. With a sol- With a symmetrical arrangement, the advantage of doubling the energy can be realized in a particularly simple and effective manner. In particular, all of the elements shown in FIG. 9 can be arranged in a common housing (not shown here). This makes it possible to provide a module that is easy to handle and with which, with simultaneous electrical control of the two actuators A, a sufficiently high total stroke SM of the release body T can be achieved with a sufficiently high mechanical energy.

FIGS. 10 and 11 show the essential physical parameters for realizing the release device of FIGS. 6 to 9, as calculated with a Simulink simulation. Various physical quantities are shown as a function of time 201 in milliseconds. Thus, in the uppermost curve of FIG. 10, the electrical voltage 202 applied to each of the actuators A1, A2 is shown in volts. These actuators are piezo actuators which can be moved by applying such a voltage. Here an approximately delta-shaped voltage pulse of 160 V is applied, which acts over a period of 50 ms. The three graphics below show the resulting stroke at various points on the release device. A stroke in micrometers is designated by the reference numeral 203. The stroke SA is the primary stroke generated by each of the two piezo actuators A1 and A2, which acts as a stroke on the drive side of the respective hydraulic transmission unit Hl or H2. This primary stroke is relatively low. Due to the transmission ratio of the respective hydraulic unit, however, a significantly increased stroke SH is achieved on its output side, which reaches almost 400 pm at the maximum of the curve. In the third graphic, a stroke in millimeters is designated by 204. Here, the described stroke SH, which acts on the drive side of the respective subsequent cable system, is compared with the stroke As, which is present in the area of the respective lateral deflection rollers 108. This stroke As is at its maximum already in the range of about 3 mm. Also In the fourth graphic, 204 is a stroke in millimeters. Here the stroke of the rope As is compared with the stroke SM that is present on the output side of the entire rope system, i.e. in the area of the release body T. As a result of the function of the respective lateral deflecting roller 108, there is an additional increase in the stroke, so that a stroke SM of approximately 7 mm is achieved for the release body T. When a travel threshold of around 3 to 4 mm is exceeded, a typical subsequent latching can be released with the release body T. This stroke threshold is reached for the stroke SM after only a few milliseconds. The requirements for the dynamics of the release device are thus met. By using two subsystems, it is also possible to achieve the mechanical energy required for triggering (in other words: the force required for a given stroke).

In the individual graphics in FIG. 11, various electrical parameters are shown which result from the simulation for the control of the two actuators A1 and A2. The top curve thus again shows the voltage 202 in volts applied to the respective piezo actuator as a function of the time 201 in milliseconds. In contrast to FIG. 10, only about the first 30 ms after the start of the voltage pulse are shown here. The second curve shows the current 205 in amperes that flows when the two piezo actuators are activated. The maximum current here is just under 7 A. The third curve shows the electrical output 206 in watts. The electrical peak power here is just under 350 W. The fourth curve shows the total electrical energy consumption 207 in mJ. Both the electrical peak power and the total energy consumed are significantly lower than with the comparable electromagnetic actuator described above, in which a peak power of 1200 W was measured.

With the release device described, the given parameters for the stroke, the dynamics and the force during the movement of the release body T can be realized, where- while at the same time the electrical peak power is significantly reduced compared to the prior art. This also has the effect that for an electrical line to the respective actuator, a significantly lower line cross-section than in the prior art can be used.

Reference character list

1 release device

3 electrical switchgear

7 hydraulic fluid

11a first chamber (drive chamber)

11b second chamber (output chamber)

13a first piston (drive piston)

13b second piston (output piston)

15a first working chamber

15b second working chamber

16 hydraulic line

17a first rear chamber

17b second rear chamber

19a first bellows element

19b second bellows element

21b output body

37 Leadership

41 pantry

43 bellows element

45 cover plate

61 first subsystem

62 second subsystem

101 rope

103 Drive body of the cable system

105 Fixing body of the cable system

107 pulley

108 side pulley

109 Output element of the cable system 201 Time in ms

202 voltage in V

203 stroke in pm

204 stroke in mm

205 current in A

206 power in W

207 energy in mJ

A actuator

Al actuator of the first subsystem A2 actuator of the second subsystem

a_0 deflection angle

a_l deflection angle

ß angle of rotation of the rope

d lateral distance

As hub in front of the side pulley

Ah height difference

F locking device

h_0 height

h_l height

H hydraulic transmission unit

Ha drive side of the hydraulic transmission unit

Hb output side of the hydraulic transmission unit

Hl hydraulic unit of the first subsystem

H2 hydraulic unit of the second subsystem

1_0 length segment

1_1 length segment

M rope system

Ma drive side of the rope system

Mb output side of the rope system

Ml rope system of the first subsystem

M2 rope system of the second subsystem

SA hub on the drive side of the hydraulic unit

SH stroke on the output side of the hydraulic unit

SM hub on the output side of the cable system

SR hub at the pantry

51 first switching contact

52 second switching contact

T release body

V pretensioning element

Claims

1. Tripping device (1) for an electrical Schalteinrich device (3) comprising

- an actuator (A),

- a hydraulic transmission unit (H) mechanically connected in series with the actuator (A),

- A cable system (M) mechanically connected in series with the hydraulic transmission unit (H), which acts as a mechanical transmission unit for the hydraulic transmission unit (H),

- and a release body (T) which can be moved by means of the cable system (M) for triggering a switching process in the

Switching device (3).

2. tripping device (1) according to claim 1, wherein the cable system (M) is designed as a pulley system with a movement-carrying cable (101) and a plurality of pulleys (107, 108).

3. tripping device (1) according to one of claims 1 or 2, wherein the cable system (M) has a transmission ratio of 0.5 or less.

4. tripping device (1) according to one of the preceding claims, in which the hydraulic transmission unit (H) and the cable system (M) together have a total transmission of 0.25 or less.

5. Trip device (1) according to one of the preceding claims, in which the trip body (T) has a stroke of at least 1 mm and in particular at least 2 mm.

6. Trip device (1) according to one of the preceding claims, in which the trip body (T) is an elongated ge shaped plunger, which is movably mounted essentially with only one translational degree of freedom.

7. tripping device (1) according to one of the preceding claims, in which the hydraulic translation unit (H) has a drive element (13a) and an output element (13b, 21b) and is designed to move the drive selements (13a) with a Transmission ratio of at most 1: 2 to be transmitted to the output element (13b, 21b).

8. tripping device (1) according to one of the preceding claims, in which the hydraulic transmission unit (H) can be filled with a hydraulic fluid (7) and has a first and a second chamber (11a, 11b) which are hydraulically connected to one another and one of which is designed as a drive chamber (11a) and the other as an output chamber (11b).

9. tripping device (1) according to claim 8, wherein at least in the first chamber (11a) a piston (13a) is movably arranged along egg ner piston axis, so that this Kol ben (13a) the first chamber (11a) in a Volume variable le working chamber (15a) and a rear chamber (17a) separates, wherein the rear chamber (17a) is at least partially limited by a bellows element (19a) with a variable axial length be.

10. Triggering device (1) according to one of claims 8 or 9, which additionally has a, in particular pressurizable, storage chamber (41) for the hydraulic fluid (7).

11. tripping device (1) according to one of the preceding claims, which has at least two mechanically parallel connected subsystems (61,63),

- each of the subsystems (61,63) having an actuator (A),

has a hydraulic transmission unit (H) connected mechanically in series with the actuator (A) and a cable system (M) mechanically connected in series with the hydraulic transmission unit (H), - the two cable systems (M) are mechanically coupled to a common, higher-level release body (T),

- So that a simultaneous control of the two actuators (A) leads to a jointly effected movement of the higher-order trigger body (T) by means of the two hydraulic transmission units (H) and the two cable systems (M).

12. Tripping device (1) according to one of the preceding claims, in which the actuator (A) is a solid-state actuator.

13. Electrical switching device (3) with a Auslösevor direction (1) according to one of the preceding claims.

14. Electrical switching device (3) according to claim 13, wel che a fixed first switching contact (Sl) and a relative to this movable second switching contact (S2) has,

wherein the triggering device (1) is designed to trigger the movement of the second switching contact (S2).

15. Electrical switching device (3) according to claim 14,

- which additionally has a biasing element (V) that is designed to bias the second switching contact (S2) relative to the first switching contact (Sl),

- and which additionally has a locking device (F) which is designed to lock the pretensioning element (V) in such a pretensioned state,

- The triggering device (1) being designed to release the locking device (F).