Switching device

Abstract

To present a switching device.SOLUTION: A switching device comprises: at least two fixing contact points; one movable contact point in a switching chamber; at least two auxiliary contact points in the switching chamber; two sprint contact points; and a contact plate. Each of the spring contact points includes a second contact region while being contacted to one of the auxiliary contact points in a first contact region, and the contact plate can be moved with the movable contact point. In a first switching state of the switching device, it is contacted to the second contact region of each spring contact point, and is arranged in a second switching state so as to be interfered from the second contact region of each spring contact point.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] A switching device is presented. [Background technology]

[0002] The switching device is especially designed as a remotely operated switch that can be driven by electric current and is electromagnetically actuated. The switching device can be actuated via a control circuit and can switch the load circuit. In particular, the switching device can be designed as a relay or as a contactor, in particular as a power contactor. Particularly preferably, the switching device can be designed as a gas-filled power contactor.

[0003] One possible application of such switching devices, in particular power contactors, is the opening and disconnection of battery circuits, for example in motor vehicles, such as electrically or partly electrically powered motor vehicles, or in applications in the field of renewable energy.

[0004] In their function as safety components, for example contactors are usually additionally monitored, which contactor monitoring is regulated in the standard IEC 60947-5-1. Contactor monitoring is intended, for example, to detect the most frequent faults of contactors, relays and switches, namely stuck or welded main contacts. Such faults, also known as contactor stuck, can be caused, for example, by arcs that form between the contacts during switching operations under load and can cause such high temperatures at the contact surfaces that they are welded together. Furthermore, it is advantageous if further fault conditions can be detected, for example when the contacts are mechanically blocked in the open position or in an intermediate state.

[0005] Typical contactors are designed as so-called overstroke systems. This means that after the main contacts have been interconnected by the switching bridge and therefore electrically closed, the movement of the closing system continues and the usually spring-loaded pressure of the switching bridge on the main contacts increases. In the case of contactor sticking, this overstroke is eliminated again, but the switching bridge remains stuck to at least one main contact. The mechanical system therefore remains in an intermediate state, neither opening nor closing properly.

[0006] Monitoring or contactor sticking detection can be done, for example, by voltage measurement across the main contacts of the contactor. If there is a voltage across the main contacts, it is inferred that the contactor is open. If there is no voltage, it is inferred from that that the contactor is short-circuited and therefore closed. This method is very reliable, but also expensive to use, since wiring loaded with high voltage potentials must be laid and properly insulated. Monitoring is usually performed by a high-level system, for example an analog-to-digital converter controlled by a microcontroller.

[0007] It is also known, for example, to use a microswitch in the switching chamber of the contactor, which is operated by a small cantilever on the switching bridge. The cantilever operates the switch just before the switching bridge is pressed against the main contacts. The switch can then be designed as a closure (closes when pressed) or an opener (opens when pressed). The signal of the microswitch can thereby also be designed inversely compared to the switching state of the contactor. A disadvantage of this solution is that the microswitch must be arranged close to the main contacts inside the switching chamber. This can sometimes affect the arc quenching or involve insulation disadvantages. Furthermore, the monitoring contact formed by the cantilever and the microswitch must be preformed. This means that the monitoring contact changes its state before the main contacts close. This is due to the fact that the microswitch must still display the "closed" state if the overstroke has already reached its limit during attachment. Intermediate states or blockages cannot thereby be detected. A further disadvantage lies in the service life of a normal microswitch, which, depending on the design, can only amount to several hundred thousand switching cycles. Furthermore, wires must be routed to the switch, limiting the use of a completely hermetically sealed ceramic discharge space.

[0008] Furthermore, auxiliary switches are known, for example from DE 10 200 03 133 A1, which are operated via a cantilever on a switching bridge, whereby for example two overlapping contacts can be pressed against each other. This solution is certainly simple, inexpensive and hardly wears out. However, it has the disadvantage that the overlapping contacts are mounted between the main contacts, which can lead to insulation problems. Furthermore, conductors leading to the auxiliary switch must be laid, which limits or makes impossible the use of a completely hermetically sealed ceramic discharge space. The switching behavior remains the same as that of a microswitch.

[0009] To avoid the above-mentioned drawbacks, it is also known, as described for example in patent EP 1 399 633 B1, to mount magnets capable of opening and closing a reed switch at the bottom of the moving system, in particular outside the switching chamber. Thereby, detection takes place far away from the main contacts and detection can also take place through non-magnetic materials. Furthermore, this solution can be easily used in conjunction with hermetically sealed ceramic discharge spaces. The switching behavior is similar to the two systems mentioned above, but the difficulty arises that the overlap area must be correctly adjusted, since the indication is done magnetically and hysteresis effects must also be taken into account. A further drawback lies in the susceptibility of the reed switch to magnetic interference fields and mechanical shocks.

[0010] As an improvement to this, it is known to use Hall sensors instead of reed switches, so that the magnetic detection is not performed by a mechanical switch, but by semiconductor components. Magnetic interference fields thus no longer play a role, and vibration dependence is no longer present. However, the switching behavior is similar to that of a reed switch.

[0011] All four monitoring switch solutions have the so-called "normally open" characteristic, i.e. the monitoring switch broadly reflects the state of the main contacts. However, signal inversion does not produce "normally closed", only "not normally open". Notably common to all four principles is that none of these solutions can reliably signal that the monitored contactor is reliably and completely open. However, such a requirement is codified in the standard IEC 60947-5-1, which requires the detection to close the monitoring contacts only when the contactor is in the idle position, or to indicate a closed monitoring contact ("normally closed").

[0012] Such a solution is hitherto unknown in gas-filled contactors. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] International Publication No. 2008 / 033349 [Patent Document 2] JP 2013-008621 A Summary of the Invention [Problem to be solved by the invention]

[0014] At least one objective of certain embodiments is to provide a switching device. [Means for solving the problem]

[0015] This problem is solved by the subject matter according to the independent claims. Advantageous embodiments and developments of the subject matter are set out in the dependent claims and are further evident from the following description and the drawings.

[0016] According to at least one embodiment, the switching device comprises at least one fixed contact and at least one movable contact. The at least one fixed contact and the at least one movable contact are intended and adjusted to switch on and off a load circuit connectable to the switching device. Particularly preferably, the switching device comprises at least two fixed contacts, which together with the movable contact are intended and adjusted to switch on and off a load circuit connectable to the switching device, in particular to the at least two fixed contacts. In the following, the switching device is described in the main as having at least one fixed contact or two fixed contacts. However, the number of fixed contacts may differ from the number specifically mentioned in the following embodiments and in relation to the features described below.

[0017] The movable contacts are movable between the disconnected and connected states of the switching device such that in the disconnected state of the switching device they are separated from the fixed contacts and thus electrically isolated, and in the connected state they have mechanical contacts to at least two fixed contacts and thus electrically connected thereto. The fixed contacts are therefore arranged separately from one another in the switching device and, depending on the state of the movable contacts, can be conductively connected to one another via the movable contacts or electrically isolated from one another. In the connected state, the movable contacts are therefore in contact with at least one contact surface of at least one fixed contact. The distance of the movable contact, in particular the above-mentioned contact surface of the movable contact, from the at least one fixed contact, in particular the above-mentioned contact surface of the at least one fixed contact, in the disconnected and therefore separated state, is here and below also referred to as the switching gap and indicates the maximum possible movement and therefore the maximum reachable distance of the contacts, in particular between their contact surfaces. In the case of, for example, two fixed contacts, the above explanation applies accordingly.

[0018] According to a further embodiment, the switching device comprises a switching chamber, in which the movable contact and the fixed contact are arranged. The movable contact can in particular be arranged completely in the switching chamber. Arranging the fixed contact in the switching chamber can in particular mean that at least the contact area of ​​the fixed contact, which in the connected state is in mechanical contact with the movable contact, is arranged inside the switching chamber. For the connection of the conductors of the circuit to be switched by the switching device, the fixed contacts arranged in the switching chamber can be electrically contactable from the outside, i.e. from outside the switching chamber. For this purpose, the fixed contacts arranged in the switching chamber can partially protrude from the switching chamber and have the possibility of connection for the conductors outside the switching chamber. Therefore, the switching chamber preferably comprises an opening through which the fixed contact protrudes into the switching chamber. The fixed contacts are for example soldered in the opening of the switching chamber and protrude into the inner space of the switching chamber and out of the switching chamber.

[0019] According to a further embodiment, the switching device comprises at least two auxiliary contacts arranged in the switching chamber. The auxiliary contacts being arranged in the switching chamber may in particular mean that at least one contact area of ​​the auxiliary contacts is arranged inside the switching chamber. For the connection of the conductor, the auxiliary contacts arranged in the switching chamber may be electrically contactable from the outside, i.e. from outside the switching chamber. For this, the auxiliary contacts arranged in the switching chamber may partially protrude from the switching chamber and may have the possibility of connection for the conductor outside the switching chamber. Thus, the switching chamber preferably comprises an opening through which the auxiliary contacts protrude into the switching chamber. The auxiliary contacts are for example soldered into the opening of the switching chamber and protrude into the inner space of the switching chamber and out of the switching chamber. The passage of the auxiliary contacts into the switching chamber may thus be carried out by a sealed, for example hard soldered, connection comparable to the passage of the fixed contacts, which may preferably be carried out in a common manufacturing step and thus in a common work process.

[0020] According to a further embodiment, the switching device comprises at least two spring contacts arranged in the switching chamber. Furthermore, the switching device comprises a contact plate arranged in the switching chamber. In particular, the spring contacts and the contact plate are arranged completely in the switching chamber. Each of the spring contacts comprises at least one first contact area and one second contact area. By means of the first contact area, each of the spring contacts can contact one of the auxiliary contacts. In particular, each of the spring contacts can contact one of the auxiliary contacts by means of its first contact area in normal operation permanently and independently of the switching state of the switching device. The first contact area of ​​the spring contacts can in particular directly and therefore mechanically contact the auxiliary contact.

[0021] According to a further embodiment, the contact plate is movable together with the movable contact. Particularly preferably, the contact plate and the movable contact can be moved together by the same mechanical drive, which will be further described below. Particularly preferably, the contact plate is in contact with the second contact area of ​​the spring contact in the first switching state of the switching device and is arranged spaced apart from the second contact area of ​​the spring contact in the second switching state. The first switching state can particularly preferably be the above-mentioned non-connected switching state of the switching device, while the second switching state can be the above-mentioned connected state. In other words, the contact plate can be in contact with the second contact area of ​​the spring contact when the movable contact is spaced apart from the at least one fixed contact, while the contact plate is spaced apart from the second contact area of ​​the spring contact when the movable contact of the switching device is in contact with the at least one fixed contact. Alternatively, the first switching state can also be a connected switching state, while the second switching state is a non-connected state. In this case, the operating principle of the detection of the state of the switching device possible via the auxiliary contact is designed inversely with respect to the following description.

[0022] According to a further embodiment, the switching device comprises a housing in which the movable contact, the fixed contact and also the auxiliary contact, the spring contact and the contact plate are arranged. The fixed contact being arranged in the housing may in particular mean that at least one contact area of ​​the fixed contact, which in the connected state is in mechanical contact with the movable contact, is arranged inside the housing. For the connection of the conductors of the circuit to be switched by the switching device, the fixed contact arranged in the housing may be electrically contactable from the outside, i.e. from outside the housing. For this purpose, the fixed contact arranged in the housing may partially protrude from the housing and have the possibility of connection for the conductors outside the housing. In particular, this may apply to any fixed switching contact. The movable contact may in particular be arranged completely in the housing. Furthermore, preferably, the auxiliary contact may also be arranged completely in the housing. The auxiliary contact may be contactable from the outside, for example via a conductor inside the housing that is conductively connected to an external electrical connection on the housing. Alternatively, there may be an electrical component in the housing, such as for example a microcontroller, which is connected to the auxiliary contact via an electrical wiring. The microcontroller may again be externally contactable via suitable connections on the housing.

[0023] According to a further embodiment, the contacts are arranged in a gas atmosphere in the housing. This may mean, in particular, that the movable contact, the spring contact and the contact plate are completely arranged in the gas atmosphere in the housing, and furthermore that at least a part of the fixed contact, for example the contact area of ​​the fixed contact, and at least a part of the auxiliary contact, for example the contact area of ​​the auxiliary contact, are arranged in the gas atmosphere in the housing. Accordingly, the switching device may particularly preferably be a gas-filled switching device, for example a gas-filled contactor. The gas atmosphere may in particular facilitate the extinction of arcs that may occur during the switching operation. The gas of the gas atmosphere may for example comprise or be a hydrogen- and / or nitrogen-containing gas, in particular under high pressure. Preferably, the gas may comprise at least 50% H2. In addition to hydrogen, the gas may comprise an inert gas, particularly preferably N2 and / or one or more noble gases.

[0024] According to a further embodiment, the switching chamber is inside the housing. Furthermore, in particular the gas, i.e. at least a part of the gas atmosphere, can be inside the switching chamber.

[0025] According to a further embodiment, the movable contact and the contact plate are movable by a mechanical drive. The mechanical drive comprises, in particular, a magnet armature. The magnet armature can comprise a shaft, which is connected at one end with the movable contact and the contact plate such that the movable contact and the contact plate are movable by the shaft, i.e. are also moved by the shaft when the shaft moves. The shaft can in particular protrude into the switching chamber through an opening in the switching chamber. In particular, the switching chamber can comprise a switching chamber bottom having an opening through which the shaft protrudes. The magnet armature can be movable by a magnetic circuit to bring about the above-mentioned switching operation. For this purpose, the magnetic circuit can comprise a yoke having an opening, through which the shaft of the magnet armature protrudes. When the magnetic circuit is switched on, the magnet armature, in particular the magnetic core of the magnet armature, can be attracted towards the yoke.

[0026] According to a further embodiment, the movable contact and the contact plate are arranged in an electrically insulating contact holder. The contact holder is particularly preferably arranged and fixed on the axis of the magnet armature and can electrically insulate the movable contact and the contact plate from the axis. Thereby, the movable contact and the contact plate can be supported in an electrically insulated state from the components of the mechanical drive, i.e. in particular from the components of the magnet armature. For this purpose, the contact holder can include or consist of an electrically insulating material. The electrically insulating material can be selected from polymers and ceramic materials, for example in particular from the structure (CHO) n The insulating layer may be selected from polyoxymethylene (POM) having the formula:

[0027] According to a further embodiment, the contact plate is fixed to the contact holder. Fixing can take place, for example, by clamping. Particularly preferably, the contact holder is partially reshaped from the material of the contact holder. For this purpose, the contact plate can be, for example, recast or overmolded with the material of the contact holder. For contacting the second contact areas of the spring contacts, the contact areas of the contact plate can protrude from the contact holder.

[0028] During the switching operation, the magnet armature, the shaft as well as the movable contact and the contact plate move in a linear motion, preferably in the form of a lifting movement along the shaft. Preferably, the shaft of the magnet armature and, for example, the magnetic core have a movement clearance for the lifting movement in the vertical direction, which is larger than the above-mentioned switching gap. This can be made possible, for example, by the gap between the magnetic core and the yoke, which may also be called the movement gap, being larger than the switching gap in the switched-off state. The magnet armature with the movable contact can thus be an overstroke system, in which the movable contact is displaceably arranged in the contact holder. Furthermore, a contact spring can be arranged in the contact holder, which exerts a spring force on the movable contact in the direction of the fixed contact. When the movable contact hits the fixed contact and thus the switching gap is completely closed, the contact spring can be compressed and the magnet armature can move further, for example until the magnetic core touches the yoke. For example, the movement gap can be larger than the switching gap by no more than 1 mm, particularly preferably by about 0.5 mm. The overstroke compresses the contact spring, thereby increasing the contact pressure of the movable contact against the fixed contact, and a degree of insensitivity to vibrations and mechanical shocks can be achieved.

[0029] By the above-mentioned design of the mechanical drive and the switching chamber, it can be achieved that the auxiliary contact, the spring contact and the contact plate are arranged in an electrically insulated state from the fixed contact, the movable contact and the mechanical drive, in particular a permanent insulation, i.e. a consistently guaranteed insulation during normal operation of the switching device, thus during the first and second switching states and during the transitions between them, can be achieved.

[0030] At least one of the contact areas of each of the spring contacts can be designed to be elastic. For example, the first contact area of ​​each spring contact can be designed to be elastic and can exert a spring force on the auxiliary contact. In other words, the first contact area can be pressed against the auxiliary contact in the assembled state and thus exert a spring force. Alternatively or additionally, the second contact area can be designed to be elastic. Particularly preferably, the second contact area can exert a spring force on the contact plate in the first switching state. The spring force of the second contact area can then be smaller than the spring force of the contact spring. Due to the elastic action of the second contact area, an increased insensitivity of the mechanical contact between the contact plate and the second contact area of ​​the spring contact to vibrations and mechanical shocks can be achieved. Particularly preferably, the spring force of the second contact area on the contact plate and therefore the counter pressure on the magnet armature, in particular the contact holder, can be smaller than the return spring force, which has a return spring of the mechanical drive and can move the magnet armature from the connected switching state to the disconnected switching state. Particularly preferably, the spring force of the second contact area against the contact plate may be less than or equal to 20% of the return spring force.

[0031] Particularly preferably, the movable contact is separated from the fixed contact by a switching gap, as described above, in the first or second switching state, and the contact plate can lose mechanical contact with the second contact area of ​​the spring contact after moving a distance of less than or equal to 20% of the switching gap when the switching device passes from the first switching state to the second switching state, whereby a very small distance can be achieved which the magnet armature has to move before contact between the contact plate and the spring contact is interrupted.

[0032] The direction of movement of the movable contacts, which corresponds to the main extension direction of the axis, i.e. the direction of the up and down movement of the movable contacts, may here and below also be referred to as the vertical direction. The fixed contacts are arranged adjacent to one another along a longitudinal direction, which lies in a horizontal plane perpendicular to the vertical direction. The movable contacts may for example be formed in the shape of a plate and may have a main extension plane parallel to the horizontal plane. A transverse direction is defined perpendicular to the vertical and longitudinal directions, so that the horizontal plane is spanned by the longitudinal and transverse directions. The auxiliary contacts are preferably arranged along the transverse direction, and the movable contacts may in particular be arranged between the auxiliary contacts along the transverse direction.

[0033] According to a further embodiment, the switching chamber has a switching chamber wall. The switching chamber wall can preferably have a rectangular cross-sectional shape or at least a cross-sectional shape that is approximately rectangular in a horizontal section, i.e. in a section along a cut plane perpendicular to the vertical direction. In particular, the switching chamber walls can have opposing longitudinal side walls and opposing lateral side walls, so that in a horizontal section they are rectangular in shape with respect to their outer and / or inner contour. In other words, the longitudinal side walls can extend substantially vertically and longitudinally, while the lateral sides can extend substantially vertically and transversely. In this case, preferably, the longitudinal side walls, the lateral side walls and the cover part with the openings for the fixed contacts and the openings for the auxiliary contacts can be designed in one piece, and the switching chamber that can form the switching chamber wall can additionally have a switching chamber bottom that forms the switching chamber together with the switching chamber wall. Alternatively, the side walls can also be designed in one piece together with the switching chamber bottom. Additionally, the side wall portion can form a switching chamber wall without the cover portion and without the switching chamber bottom portion, which together with a separately manufactured cover portion and a separately manufactured switching chamber bottom portion form a switching chamber.

[0034] According to a further embodiment, each of the spring contacts comprises a connection region extending along the longitudinal side wall between the first and second contact regions, the first and second contact regions of each of the spring contacts preferably extending from the respective longitudinal side wall at least along the transverse direction into the interior space of the switching chamber.

[0035] According to a further embodiment, the switching chamber comprises at least two webs, each of which is arranged between at least two fixed contacts in the longitudinal direction and each of which extends laterally from at least one longitudinal side wall into the switching chamber. In this case, the webs are spaced apart from one another in the longitudinal direction. In particular, the two webs can extend laterally beyond the movable contact in the interior space of the switching chamber from one of the longitudinal side walls to the other of the longitudinal side walls. In this case, the at least two webs each comprise a recess, in which the movable contact can move during the switching operation. Furthermore, the webs can be directly connected to the cover part of the switching chamber. In particular, the webs can extend directly adjacent to the cover part of the switching chamber along it. The webs can be particularly preferably designed in one piece together with the side walls and / or the cover part of the switching chamber.

[0036] By means of the at least two webs, one or more spaces can be formed between the fixed contacts in the internal space of the switching chamber, which spaces are at least partially separated from the fixed contacts and thus electrically insulated. In the at least one insulated space thus formed, and thus between the two webs in the longitudinal direction, in particular the auxiliary contact and the spring contact can be arranged. Particularly preferably, the auxiliary contact can be arranged between the two webs symmetrically with respect to the movable contact, i.e. symmetrically with respect to a symmetry plane spanned by the longitudinal and vertical directions. Furthermore, the spring contact can also be arranged symmetrically with respect to the movable contact between the two webs. Due to the formation of at least one of the webs between the auxiliary contact and the fixed contact, respectively, and between the spring contact and the fixed contact, respectively, the auxiliary contact and the spring contact can be at least partially insulated from the fixed contact. Furthermore, further additional components can be arranged in the thus formed insulated space, such as, for example, a gas-filling nozzle for filling the above-mentioned gas for forming a gas atmosphere in the switching chamber.

[0037] According to a further embodiment, the switching chamber bottom has walls which are arranged in the longitudinal direction between the webs of the switching chamber walls and between which the spring contacts are arranged. In particular, the walls can be arranged interposed between the webs and can form an intermediate space in which the spring contacts are partially arranged. Furthermore, the contact area of ​​the contact plate can be arranged in this intermediate space and can move within this intermediate space when changing from the first switching operation to the second switching operation and vice versa. The walls of the switching chamber bottom can form at least one of the above-mentioned insulated spaces together with the webs.

[0038] According to further embodiments, the auxiliary contacts and / or the spring contacts and / or the contact plates comprise a material containing copper or a copper alloy. Particularly preferably, the material may be selected from CuBe, CuSn4, CuSn6. Such materials may exhibit good electrical conductivity and a low tendency to weld. Furthermore, for example, the auxiliary contacts may comprise the same material as the fixed contacts.

[0039] In the switching device described herein, it can be achieved that the auxiliary contacts are electrically connected to one another in a first switching state and electrically separated from one another in a second switching state by means of the spring contact and the contact plate. By measuring the electrical resistance between the auxiliary contacts, the first switching state, which particularly preferably corresponds to a non-connected switching state, and the second switching state, which particularly preferably corresponds to a connected switching state, can be determined.

[0040] Further advantages, advantageous embodiments and developments emerge from the exemplary embodiments described below in conjunction with the drawings. [Brief description of the drawings]

[0041] [Figure 1] FIG. 2 is a schematic diagram of a switching device. [Figure 2A]2 is a schematic diagram of a portion of a switching device according to one embodiment; [Figure 2B] 1 is a schematic diagram of a portion of a switching device according to one embodiment; [Figure 2C] 5 is a schematic diagram of a contact plate of a switching device according to another embodiment; [Figure 2D] 4 is a schematic diagram of a switching chamber wall of a switching device according to another embodiment; [Figure 2E] 4 is a schematic diagram of a switching chamber wall of a switching device according to another embodiment; [Figure 2F] 4 is a schematic diagram of a switching chamber wall of a switching device according to another embodiment; [Figure 2G] 13 is a schematic diagram of a bottom of a switching chamber of a switching device according to another embodiment; FIG. [Figure 3A] 2 is a schematic diagram of a portion of a switching device in various switching states; [Figure 3B] 2 is a schematic diagram of a portion of a switching device in various switching states; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] In the examples and figures, identical, similar or equivalently functioning elements may be respectively provided with the same reference numerals. The illustrated elements and their size ratios with respect to each other are not to scale, rather, individual elements such as layers, components, members and regions may be shown exaggeratedly large for better illustration and / or understanding.

[0043] In Fig. 1, an example of a switching device 100 is shown, which can be used, for example, for switching high currents and / or high voltages and can be a relay or a contactor, in particular a power contactor. In Fig. 1, a three-dimensional cross-sectional view is shown according to a vertical cutting plane. It should be understood that the illustrated geometry is only exemplary and not limiting, and can be designed in other ways.

[0044] The exemplary switching device 100 comprises two fixed contacts 2, 3 and one movable contact 4 in a housing 1. The movable contact 4 is designed as a contact plate. The fixed contacts 2, 3 together with the movable contact 4 form a switching contact. Instead of the number of contacts shown, other numbers of fixed and / or movable contacts are also possible. The housing 1 is primarily used as a contact protection for the components arranged inside and comprises or consists of a plastic, such as, for example, PBT or glass-fiber-filled PBT. The fixed contacts 2, 3 and / or the movable contact 4 can comprise or consist of, for example, Cu, a Cu alloy, one or more refractory metals, such as, for example, Wo, Ni and / or Cr, or a mixture of the above-mentioned materials, for example a mixture of copper and at least one other metal, such as Wo, Ni and / or Cr.

[0045] In Fig. 1 the switching device 100 is shown in an idle state with the movable contact 4 separated from the fixed contacts 2, 3, thus the contacts 2, 3, 4 are electrically isolated from each other. It should be understood that the illustrated embodiment of the switching contacts and in particular their geometrical shape are purely exemplary and not limiting. Alternatively, the switching contacts can be designed in other ways.

[0046] The switching device 100 comprises a mechanical drive with a movable magnet armature 5 which performs a substantial switching movement. The magnet armature 5 comprises a magnetic core 6, which for example comprises or consists of a ferromagnetic material. The magnet armature 5 further comprises a shaft 7 which is led through the magnetic core 6 and is rigidly connected to the magnetic core 6 at one axial end. At the other axial end opposite the magnetic core 6, the magnet armature 5 comprises a movable contact 4 which is supported via a contact spring 40 and which is also connected to the shaft 7. The shaft 7 can preferably comprise or be manufactured from special steel. To electrically insulate the movable contact 4 from the shaft 7, an electrically insulating contact holder 47, which may also be called a bridge insulator, can be arranged between them.

[0047] The magnetic core 6 is surrounded by a coil 8. A current in the coil 8, which can be connected externally via a control circuit, generates an axial movement of the magnetic core 6 and thus of the entire magnet armature 5 until the movable contact 4 comes into contact with the fixed contacts 2, 3. In the illustrated example, the magnet armature moves upwards. The magnet armature 5 thus moves from a first position, which corresponds to the illustrated idle state and at the same time to the disconnected or non-connected state and therefore to the switched-off state, to a second position, which corresponds to the active or connected state and therefore to the switched-on state. In the active state, the contacts 2, 3, 4 are electrically connected to one another.

[0048] For guiding the shaft 7 and thus the magnet armature 5, the switching device 100 comprises a yoke 9, which may comprise or consist of pure iron or a lightly doped iron alloy and which forms part of the magnetic circuit. The yoke 9 comprises an opening inside which the shaft 7 is guided. When the current in the coil 8 is interrupted, the magnet armature 5 is moved again to the first position by one or more springs 10, which may also be called return springs. In the illustrated example, the magnet armature 5 therefore moves downwards again. The switching device 100 is then again in an idle state with the contacts 2, 3, 4 open.

[0049] The direction of movement of the magnet armature 5 and thus of the movable contact 4 is also referred to below as the vertical direction 91. The arrangement direction of the fixed contacts 2, 3 perpendicular to the vertical direction 91 is referred to below as the longitudinal direction 92. The direction perpendicular to the vertical direction 91 and perpendicular to the longitudinal direction 92 is referred to below as the transverse direction 93. The directions 91, 92 and 93, which are valid independently of the switching movement described, are shown in the figures for ease of directional perception.

[0050] For example, when the contacts 2, 3, 4 are opened, at least one arc may occur, which may damage the contact surfaces of the contacts 2, 3, 4. There may then be a risk that the contacts 2, 3, 4 "stick" to one another due to welding caused by the arc and are no longer separated from one another. The switching device 100 is then still in the switched-on state, even though the current in the coil 8 has to be switched off and thus the load circuit disconnected. In order to prevent the occurrence of such an arc, or at least to facilitate the extinction of any arc that does occur, the contacts 2, 3, 4 are arranged in a gas atmosphere, so that the switching device 100 is designed as a gas-filled relay or gas-filled contactor. For this, the contacts 2, 3, 4 inside the switching chamber 11 formed by the switching chamber wall 12 and the switching chamber bottom 13 are arranged in a gas-tight region 14 formed by the hermetically closed parts, and the switching chamber 11 may be part of the gas-tight region 14. The gas-tight region 14 is substantially formed by the switching chamber 11, the yoke 9 and a part of the additional wall. The gas-tight region 14 completely surrounds the magnet armature 5 and the contacts 2, 3, 4, except for those parts of the fixed contacts 2, 3 intended for external connection. The gas-tight region 14, and thus also the inner space 15 of the switching chamber 11, is filled with gas. The gas which can be filled into the gas-tight region 14 through a gas-filling nozzle in the context of the manufacture of the switching device 100, can be particularly preferably a hydrogen-containing gas, for example comprising more than 20% H2 in an inert gas or alternatively 100% H2, since this can promote the extinction of the arc.

[0051] Outside the switching chamber 11 there may additionally be present, for example, a permanent magnet (not shown) intended and arranged to deflect the arc, a so-called blow-out magnet, which in particular can result in an extension of the arc path and thus improve the extinction of the arc.

[0052] The switching chamber wall 12 and the switching chamber bottom 13 can be made of or from metal oxides, such as, for example, Al2O3. Furthermore, plastics with a sufficiently high temperature stability, such as, for example, PEEK, PE and / or glass-fiber-filled PBT, are also suitable. Alternatively or additionally, the switching chamber 11 can be at least partially made of, in particular, the structure (CHO) n Such plastics may also include POM having a relatively low carbon content and a very low tendency to form graphite. In particular, (CHO) n In the case of , the same carbon and oxygen content can lead to the evolution of mainly gaseous CO and H2 during thermally induced, and especially arc induced, decomposition. Additional hydrogen can enhance arc extinction.

[0053] In relation to the following figures, an embodiment of a switching device 100 and its components enabling detection of a switching state is described, which may be designed similarly to the switching device described in relation to figure 1, except for the features described below. In order to more easily perceive the directions and cut planes, directions 91, 92, 93 are indicated in the following figures.

[0054] In Figures 2A and 2B a section of the switching device 100 is shown based on a three-dimensional cross-section and a two-dimensional cross-section, essentially showing the area of ​​the switching chamber 11. The cut planes of the cross-sections of Figures 2A and 2B are perpendicular to the longitudinal direction 92, respectively. In Figure 2C the contact plate 31 is shown. In Figures 2D-2F various views of the switching chamber 11 and the switching chamber wall 12 are shown, and in Figure 2G the switching chamber bottom 13 is shown. The following description equally relates to Figures 2A-2G.

[0055] Compared to the switching device of Figure 1, the embodiment shown in Figures 2A to 2G comprises two auxiliary contacts 25 which are arranged in openings 125 in the switching chamber wall 12 and which, like the fixed contacts 2, 3, protrude into the internal space 15 of the switching chamber 11.

[0056] Between the auxiliary contacts 25 arranged along the transverse direction 93, in the illustrated embodiment, further openings 126 are formed in which gas filling nozzles 26 are arranged. The gas filling nozzles 26 can be used to fill the gas of the gas atmosphere into the gas-tight region. After filling, it can be closed, for example by squeezing.

[0057] The auxiliary contact 25 and the gas-filled nozzle 26 are preferably soldered in the openings 125, 126 of the switching chamber 11, so that the passage of the auxiliary contact 25 and the gas-filled nozzle 26 into the switching chamber 11 is effected by a hermetically sealed, e.g. hard-soldered, connection comparable to the passage of the fixed contacts 2, 3. The assembly of the contacts 2, 3 and the auxiliary contact 25 as well as the gas-filled nozzle 26 can preferably be effected in a common working step.

[0058] The auxiliary contacts 25 are disposed entirely within the housing and may be externally accessible, for example via conductors 27 inside the housing that are conductively connected to external electrical connections on the housing.

[0059] Furthermore, the switching device 100 comprises two spring contacts 30 and one contact plate 31 arranged in the switching chamber 11. In particular, the spring contacts 30 and the contact plate 31 are arranged completely in the internal space 15 of the switching chamber 11. Each of the spring contacts 30 extends from the auxiliary contact 25 to the contact plate 31 and comprises at least a first contact area 301 and a second contact area 302. By means of the first contact area 301, each of the spring contacts 30 is in contact with one of the auxiliary contacts 25. In particular, each of the spring contacts 30 can, in normal operation, be in contact with one of the auxiliary contacts 25 by means of its first contact area 301 permanently and independently of the switching state of the switching device 100. As can be seen, the first contact area 301 of the spring contact 30 is in direct and therefore mechanical contact with the auxiliary contact 25.

[0060] The contact plate 31 is movable together with the movable contact 4. For this, the contact plate 31 and the movable contact 4 are both connected to a mechanical drive device as described above in connection with FIG. 1. The contact plate 31 is in contact with the second contact area 302 of the spring contact 30 in the first switching state of the switching device 100 shown in FIGS. 2A and 2B. For this, the contact plate 31 comprises a contact area 312, as shown in FIG. 2C. In the first switching state, the second contact area 302 of the spring contact 30 is in mechanical and therefore electrical contact with the contact area 312 of the contact plate 31, so that the spring contacts 30, and thus also the auxiliary contact 25, are conductively connected to one another via the contact plate 31.

[0061] As will be explained further below, in the second switching state, the contact plate 30 is arranged spaced apart from the second contact area 302 of the spring contact 30. The first switching state, in the illustrated embodiment, is the non-connected switching state of the switching device 100 described above, in which the movable contact 4 is spaced apart from the fixed contacts 2, 3 and correspondingly a switching gap exists between the movable contact 4 and the fixed contacts 2, 3.

[0062] The movable contact 4 and the contact plate 31 are arranged in an electrically insulating contact holder 47. The contact holder 47 is provided with an opening through which the shaft 7 is inserted and is fixed to the shaft 7 of the magnetic armature 5 and thus of the mechanical drive of the switching device 100. The contact holder 47 can be made in one piece or in multiple pieces.

[0063] The movable contact 4 and the contact plate 31 are electrically insulated from the shaft 7 by a contact holder 47. Thereby, the movable contact 4 and the contact plate 31 are supported in an electrically insulated manner from the components of the mechanical drive, i.e. in particular from the components of the magnet armature 5. The contact holder can for this purpose, for example, have the structure (CH2O) n The insulating material may comprise or consist of an electrically insulating material selected from polymeric and ceramic materials, such as polyoxymethylene (POM), polybutylene terephthalate (PBT), glass fiber filled PBT, and electrically insulating metal oxides, e.g. Al2O3.

[0064] The contact plate 31 is fixed to the contact holder 47. The fixing can take place, for example, by clamping or, as shown, particularly preferably by remolding. For this purpose, the contact plate 31 is partially remolded, for example recast or overmolded, from the material of the contact holder 47. For the contact of the second contact areas 302 of the spring contacts 30, the contact areas 312 of the contact plate 31 protrude from the contact holder 47 in the lateral direction 93.

[0065] 2C, the contact plate 31 is, for example, disk-shaped and has a central opening 313 through which the shaft 7 protrudes in the assembled state. Furthermore, the contact plate 31 can, as shown, have fastening holes 314 through which the material of the contact holder 47 can reach, so that the contact plate 31 can be fixed to the contact holder 47 and protected, for example against twisting.

[0066] The contact holder 47 further comprises a lower stop 471 and an upper stop 472. The contact plate 31 is arranged in the lower stop 471, which can rest on the switching chamber bottom 13 in the first switching state. The mobile contact 4 contacts the upper stop 472 in the first switching state. Between the mobile contact 4 and the lower stop 471 is arranged the contact spring 40 described in Figure 1, which for clarity is not shown in Figures 2A and 2B but which presses the mobile contact 4 against the upper stop 472 and thus in the direction of the fixed contacts 2, 3.

[0067] The magnetic armature with the movable contact 4 is an overstroke system in which the movable contact 4 is displaceably arranged in a contact holder 47. When the movable contact 4 rests against the fixed contacts 2, 3 and thus the switching gap is completely closed, the contact spring can be compressed and the magnetic armature can move further, for example until the magnetic core touches the yoke. For example, the magnetic armature can move further above the movable contact 4 in the vertical direction 91 by a distance of less than 1 mm, particularly preferably about 0.5 mm. The overstroke compression of the contact spring allows the contact pressure of the movable contact 4 on the fixed contacts 2, 3 to be increased and a certain degree of insensitivity to vibrations and mechanical shocks can be achieved.

[0068] The switching chamber wall 12, as can be seen in particular in Figs. 2D-2F, has a rectangular cross-sectional shape in horizontal section or at least approximates a rectangular cross-sectional shape, which may for example have rounded corners as shown. The switching chamber wall 12 has opposing lateral sidewalls 121 and opposing longitudinal sidewalls 122, which at least approximate a rectangular shape. The lateral sidewalls 121, the longitudinal sidewalls 122 as well as the cover part 119 with the openings 120 for the fixed contacts 2, 3 and the openings 125, 126 for the auxiliary contact 25 and the gas-filled nozzle 26 are formed in one piece, as shown in the illustrated embodiment, and form the switching chamber wall 12. Alternatively, the sidewalls 121, 122 can also be formed in one piece together with the switching chamber bottom 13. Additionally, the side walls 121, 122 can form the switching chamber walls 12 without a cover part and without a switching chamber bottom, which can then form the switching chamber 11 together with a separately manufactured cover part and a separately manufactured switching chamber bottom 13. Particularly preferably, the switching chamber walls 12 are formed from the ceramic material mentioned above.

[0069] Each of the spring contacts 30 comprises a connection region 303 between first and second contact regions 301, 302, which extends along the longitudinal side wall 122, as can be seen in Figures 2A and 2B. The first and second contact regions 301, 302 of each of the spring contacts 30 may preferably extend from the respective longitudinal side wall 122 into the interior space 15 of the switching chamber 11 at least along the transverse direction 93.

[0070] The spring contacts 30 and / or the contact plate 31 preferably comprise a material containing copper or a copper alloy. Particularly preferably, the material may be selected from CuBe, CuSn4, CuSn6. Such materials may exhibit good electrical conductivity and a low tendency to weld. The auxiliary contacts 25 may be formed from the materials mentioned above for the fixed contacts 2, 3 or from the materials described for the spring contacts 30 and / or the contact plate 31.

[0071] The spring contacts 30 are preferably formed in the form of a tape, in particular as a metal tape, as shown. At least one of the contact areas 301, 302 of each of the spring contacts 30 may be formed to be elastic. For example, the first contact area 301 of each spring contact 30 may be formed to be elastic and may exert a spring force on the auxiliary contact 25. The first contact area 301 may thus press against the auxiliary contact 25 in the assembled state, and thus exert a spring force.

[0072] Furthermore, alternatively or additionally, the second contact area 302 is formed elastically. Particularly preferably, the second contact area 302 exerts a spring force on the contact plate 31, in particular on its contact area 312, in the first switching state. Due to the elastic effect of the second contact area 302, an increased insensitivity of the mechanical contact between the contact plate 31 and the second contact area 302 of the spring contact 30 to vibrations and mechanical shocks can be achieved. Particularly preferably, the spring force of the second contact area 302 on the contact plate 31, and thus the counter pressure on the magnet armature, in particular on the contact holder 47, can be smaller than the return spring force of the return spring of the mechanical drive, which moves the magnet armature from the connected state to the disconnected state. Particularly preferably, the spring force of the second contact area 302 on the contact plate 31 can be less than 20% of the return spring force.

[0073] As can be seen in particular in Figures 2D and 2E, the switching chamber 11 comprises at least two webs 123, each of which is arranged between at least two fixed contacts 2, 3 in the longitudinal direction 92 and each of which extends from at least one longitudinal side wall 122 in the transverse direction 93 into the switching chamber 11. The webs 123 are spaced apart from one another in the longitudinal direction 92. In particular, the webs 123 extend in the transverse direction 93 beyond the movable contact 4 in the interior space 15 of the switching chamber 11 from one of the longitudinal side walls 122 to the other of the longitudinal side walls 122. Furthermore, the webs 123 each comprise a recess 124, in which the movable contact 4 can move during the switching operation. As shown, the webs 123 can be connected, preferably directly, to the cover part 119 of the switching chamber wall 12. In particular, the web 123 can extend along the switching chamber 11 and directly adjacent to the cover part 119. The web 123 is particularly preferably formed in one piece together with the side wall part 122 and the cover part 119 of the switching chamber 11.

[0074] The web 123 defines an area in the interior space 15 between the fixed contacts 2, 3, which is at least partially separated and thus electrically insulated by the fixed contacts 2, 3. In the thus defined insulated space 127, the auxiliary contact 25, the spring contact 30 and the gas-filled nozzle 26 are arranged.

[0075] Particularly preferably, the auxiliary contact 25 is arranged symmetrically with respect to the movable contact 4 between the two webs 123. Correspondingly, the spring contact 30 is also arranged symmetrically with respect to the movable contact 4 between the two webs 123. Due to the formation of at least one of the webs 123 between the auxiliary contact 25 and the fixed contacts 2, 3, respectively, and between the spring contact 30 and the fixed contacts 2, 3, the auxiliary contact 25 and the spring contact 30 are at least partially insulated from the fixed contacts 2, 3.

[0076] As shown in Fig. 2G, the switching chamber bottom 13, which is particularly preferably made of POM, comprises a bottom plate 130 with an opening 131 for the shaft 7 to pass through. At least partially surrounding the edge of the bottom plate 130, the switching chamber bottom 13 comprises a side wall 132 which can be continued into the side walls 121, 122 of the switching chamber wall 12 when assembling the switching chamber 11. The bottom plate 130 can serve as a counter stop for the lower stop 471 of the contact holder 47 at least in some areas around the opening 131. For mechanical stabilization, the bottom plate 130 can also be provided with, for example, intersecting webs, as shown.

[0077] Furthermore, the switching chamber bottom 13 comprises walls 133 on both sides of the opening 131, which are arranged adjacent to each other along the longitudinal direction 92 between the webs 123 of the switching chamber wall 12 and between which the spring contact 30 is arranged. In particular, the wall 133 is arranged inserted between the webs 123 and forms an intermediate space in which the spring contact 30 is partially arranged. To fix the spring contact 30, a fixing groove 134 may be present in the wall 133, as can be seen in FIG. 2G. Furthermore, the contact area 312 of the contact plate 31 is arranged in this intermediate space and moves in the vertical direction 91 inside this intermediate space when changing from the first switching operation to the second switching operation and vice versa.

[0078] In Figures 3A and 3B a section of switching device 100 is shown corresponding to the view of Figure 2A. In Figure 3A switching device 100 is shown in a first switching state as in Figure 2A, whereas in Figure 3B switching device 100 is shown in a second switching state. The components and features of switching device 100 shown in Figures 3A and 3B correspond to the components and features described in connection with the previous figures. Therefore, for the sake of clarity, no further reference numerals are shown in Figures 3A and 3B.

[0079] In the first switching state, the movable contact is separated from the fixed contact by a switching gap, as described above, so that the switching device 100 is in a non-connected switching state, while the contact plate is in electrical contact with the second contact area of ​​the spring contact and thus also with the auxiliary contact. The auxiliary contacts are thereby conductively connected to each other. In the second switching state, the movable contact and the contact plate are pushed upwards by the magnet armature in the direction of the fixed contact. In particular, the movable contact is electrically connected to the fixed contact, so that the switching device is in a connected switching state. On the contrary, the contact plate is electrically insulated from the spring contact, so that the auxiliary contacts are also electrically insulated from each other. Thus, for example, a resistive measurement of the electrical resistance between the auxiliary contacts allows detection of the switching state of the switching device.

[0080] The second contact areas of the spring contacts are designed such that when the switching device transitions from the first to the second switching state, the contact plate loses mechanical contact with the second contact areas of the spring contacts after moving a distance that is not greater than 20% of the switching gap, so that the distance that the magnet armature has to move on the way from the first to the second switching state before the contact between the contact plate and the spring contact is interrupted is very small. The second contact areas of the spring contacts are particularly preferably formed and bent upwards in such a way that when they come into contact with the contact areas of the contact plate as the magnet armature and thus the contact plate descend to the lower stop of the magnet armature, they are pressed down by about 0.5 mm and accordingly the magnet armature and thus the contact plate lose contact with the contact plate after a corresponding distance.

[0081] If the mechanical drive is switched off and the switching device should return to the first switching state, but the movable contact remains in the connected state due to adhesion or mechanical failure, the contact plate remains separated from the second contact area of ​​the spring contact, so that the first switching state is not read at the auxiliary contact. This is also possible taking into account the overstroke, because although the magnet armature together with the contact plate falls downwards in the direction of the switching chamber bottom by a certain distance compared to the movable contact, strictly speaking, the distance between the contact plate and the second contact area of ​​the spring contact is still large enough that no unambiguously conductive connection is created between the auxiliary contacts. The mechanical effect of the impact follows the properties of the mechanical drive and the movable contact, which means that the electrical contact of the auxiliary contacts to each other accurately indicates an incomplete opening, even after the movable contact has been detached from the fixed contact by acceleration. Thus, the switching device described here allows a reliable detection of the "surely open" state, combining this with a simple mechanism for detecting and directing signals from the sealed switching chamber.

[0082] A further advantage lies in the very cheap production, since no wiring or integrated circuits are required. Furthermore, there can be no magnetic influences on the detection. Furthermore, the detection of the switching state is performed far away from the main contacts, i.e. far away from the fixed and moving contacts, so that no problems arise with regard to insulation or with regard to the risk of destruction by switching arcs.

[0083] The realization according to the standard IEC 60947-5-1 in this form allows the detection of the condition "switching device cannot be closed", i.e. the movable system is blocked in the open position. Detection of whether the switching device has been moved to the disconnected state also takes place if the upper part of the switching device is destroyed.

[0084] The features and embodiments described in relation to the drawings can be combined with each other according to further embodiments, even if not all combinations are explicitly described. Furthermore, the embodiments described in relation to the drawings can alternatively or additionally have further features according to the description in general part.

[0085] The invention is not limited thereto by the description based on the examples, but rather includes all novel features and all combinations of features, including in particular all combinations of features in the claims, even if the feature or combination itself is not explicitly set out in the claims or examples. [Explanation of symbols]

[0086] 1. Housing 2, 3 fixed contacts 4 Movable contacts 5 Magnet Armature 6 magnetic core 7-axis 8 Coils 9. York 10 Spring 11 Switching Chamber 12 Switching chamber wall 13 Bottom of switching chamber 14 Airtight Zone 15. Interior Space 25 Auxiliary Contact 26 Gas filling nozzle 27 Conductor 30 Spring Contact 31 Connection plate 40 Contact Spring 47 Contact holder 91 vertical direction 92 Longitudinal 93 Horizontal 100 Switching Device 119 Cover part 120 aperture 121 Horizontal side wall 122 Longitudinal side wall 123 Web 124 Recess 125 Aperture for auxiliary contact 126 Opening for gas-filled nozzle 127 Space 130 Bottom plate 131 Aperture 132 Side wall 133 Wall 301, 302 contact area 303 Connection Area 312 Contact area 313 Aperture 314 fixing hole 471, 472 Stopper

Claims

[Claim 1] A switching device (100), comprising: - at least two fixed contacts (2, 3) and one movable contact (4) in a switching chamber (11); - at least two auxiliary contacts (25), two spring contacts (30) and a contact plate (31) in said switching chamber, - each of said spring contacts contacts said auxiliary contact at a first contact area (301) and has a second contact area (302); - the contact plate is movable together with the movable contact; - in a first switching state of the switching device, the contact plate is in contact with the second contact area of ​​the spring contact and in a second switching state, the contact plate is arranged spaced apart from the second contact area of ​​the spring contact.

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