switching device

Abstract

Switching device (100) comprising two fixed contacts (2, 3) and a rotary contact bridge (4) in a switching chamber (11) in a gas-tight region (16) containing H2, wherein- the rotary contact bridge is rotatable about a rotation axis (99),- in a first switching state, the fixed contacts are electrically conductively connected by the rotary contact bridge,- in a second switching state, the rotary contact bridge is rotated about the rotation axis relative to the first switching state and the fixed contacts are electrically separated from one another,- the rotary contact bridge has an electrically conductive element (40) which, for contacting each of the fixed contacts, has a contact piece (41) on a side facing away from the rotation axis in the radial direction, and the contact pieces are spring-mounted.

Description

[0001] A switching device is specified.

[0002] The switching device is designed, in particular, as an electromagnetically acting, remotely operated switch operable by electrically conductive current. The switching device can be activated via a control circuit and can switch a 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 for such switching devices, in particular power contactors, is the opening and disconnecting of battery circuits, for example in motor vehicles such as electric or partially electric vehicles. These can be, for example, purely battery-powered vehicles (BEV: "Battery Electric Vehicle"), hybrid electric vehicles that can be charged via a socket or charging station (PHEV: "Plug-in Hybrid Electric Vehicle"), and hybrid electric vehicles (HEV: "Hybrid Electric Vehicle"). In this case, both the positive and negative contacts of the battery are usually disconnected using a power contactor. This disconnection occurs during normal operation, for example when the vehicle is at rest, as well as in the event of a malfunction such as an accident or similar. The task of the power contactor is to de-energize the vehicle and interrupt the flow of current.

[0004] In conventional contactors, a movable contact bridge is raised and lowered for switching and is thus electrically connected to or separated from fixed main contacts by a linear movement. The load circuit can be connected to the main contacts. In particular, when the contacts open under load, a switching arc usually forms between the fixed contacts and the contact bridge. To prevent damage and so-called sticking of the contacts, i.e. permanent adhesion of the contact bridge to one or both fixed contacts, it is important to prevent the switching arcs that occur when the contacts are opened and closed, or at least to extinguish them as quickly as possible. The switching capacity of the switching device is crucial here: the higher the applied voltage and the higher the current flowing, the more difficult it is to extinguish any switching arcs that occur.The larger the gap between the contact bridge and the fixed contacts when the contact bridge is lowered, the easier it is to extinguish a switching arc. Therefore, the gap cannot be chosen arbitrarily small, which imposes limitations on, for example, reducing the size of the contactor.

[0005] Switching devices are described in the publications DE 10 2011 118 713 A1, DE 10 2012 000 441 A1, US 2,952,755 A, and US 2,775,666 A. US 3,008,070 A describes a rotary solenoid.

[0006] At least one object of certain embodiments is to provide a switching device.

[0007] This object is achieved by a subject matter according to the independent patent claim. Advantageous embodiments and further developments of the subject matter are characterized in the dependent claims and will further become apparent from the following description and the drawings.

[0008] According to at least one embodiment, a switching device has at least one fixed contact and at least one rotary contact bridge. The at least one fixed contact and the at least one rotary contact bridge are provided and configured to switch a load circuit connectable to the switching device on and off. Particularly preferably, the switching device has at least two fixed contacts, which are arranged separately from one another in the switching device and to which the load circuit can be connected. The fixed contacts and the rotary contact bridge can also be briefly referred to below as "contacts" or "switching contacts."

[0009] The rotary contact bridge is rotatable about a rotation axis and is thus designed as a rotatable contact. The rotary contact bridge is rotatable in the switching device such that the rotary contact bridge can switch between a first switching state and a second switching state. In the first switching state, which is a switched-on state of the switching device, the fixed contacts are electrically connected to one another by the rotary contact bridge, so that the current of a connected load circuit can flow through the switching device and in particular through the fixed contacts and the rotary contact bridge. For example, a pair of two fixed contacts can be electrically connected to one another in this way. However, it may also be possible for more than two fixed contacts to be electrically connected to one another in the first switching state.In the second switching state, which is a non-switching state of the switching device and in which the rotary contact bridge is rotated about the axis of rotation relative to the first switching state, the fixed contacts are electrically separated from one another. The first and second switching states can also be referred to below as the first and second states for short. Particularly preferably, the fixed contacts in the first state are in mechanical contact with the rotary contact bridge and are thus galvanically connected to it, while the fixed contacts in the second state are mechanically and thus also galvanically separated from the rotary contact bridge. In particular, switching between the first and second switching states is possible by rotating the rotary contact bridge by an angle of greater than or equal to 10° and less than or equal to 170°, for example 90°.

[0010] According to a further embodiment, the rotary contact bridge has an electrically conductive element which, in the first switching state, assumes a galvanically conductive position and contacts the fixed contacts, thereby establishing an electrical connection between the fixed contacts. The electrically conductive element has a contact piece on a side facing away from the axis of rotation in the radial direction for contacting each of the fixed contacts. In the first switching state, each of the contact pieces of the electrically conductive element is in mechanical contact with a contact surface of a contact area of a fixed contact. In the second switching state, the rotary contact bridge is rotated relative to the first switching state such that the contact pieces are galvanically separated from the fixed contacts.

[0011] The at least one fixed contact and / or at least the electrically conductive element of the rotary contact bridge can, for example, be made of or with Cu, a Cu alloy, one or more high-melting metals such as W, Ni, and / or Cr, or a mixture of the aforementioned materials, for example, copper with at least one other metal, such as W, Ni, and / or Cr. Furthermore, composite materials comprising metal oxide particles in a metal matrix are also conceivable. Such a composite material particularly preferably comprises or is made of aluminum oxide particles in a copper matrix.

[0012] According to a further embodiment, the switching device has a housing in which the rotary contact bridge and the at least one fixed contact or the at least two fixed contacts are arranged. The rotary contact bridge can in particular be arranged entirely in the housing. The fact that a fixed contact is arranged in the housing can in particular mean that at least one contact region of the fixed contact and in particular a contact surface of the contact region which is in mechanical contact with the rotary contact bridge in the switched-on state, is arranged within the housing. In order to connect a supply line of a load circuit to be switched by the switching device, a fixed contact arranged in the housing can be electrically contactable from the outside, i.e. from outside the housing.For this purpose, a fixed contact arranged in the housing can protrude with a part out of the housing and have a connection option for a supply line outside the housing.

[0013] According to a further embodiment, the switching device has a switching chamber in which the rotary contact bridge and the at least one fixed contact or the at least two fixed contacts are arranged. The switching chamber can in particular be arranged in the housing. The rotary contact bridge can particularly preferably be arranged entirely in the switching chamber. The fact that a fixed contact is arranged in the switching chamber can in particular mean that at least one contact region of the fixed contact and in particular a contact surface of the contact region, which is in mechanical contact with the rotary contact bridge in the switched-on state, is arranged within the switching chamber. In order to connect a supply line of a load circuit to be switched by the switching device, a fixed contact arranged in the switching chamber can be electrically contactable from the outside, i.e. from outside the switching chamber.For this purpose, a fixed contact arranged in the switching chamber can protrude with a part out of the switching chamber and have a connection option for a supply line outside the switching chamber.

[0014] According to a further embodiment, the switching device has a drive unit by means of which the rotary contact bridge can be rotated to change the switching state. For this purpose, the switching device can have an axle which is connected at one end to the rotary contact bridge in such a way that the rotary contact bridge can be moved by means of the axle, i.e. is also rotated by the axle when the axle rotates. The axle thus particularly preferably defines the axis of rotation of the rotary contact bridge, so that in the following the term "axle" can also mean "axis of rotation". The rotary contact bridge is particularly preferably attached to the axle. In particular, the rotary contact bridge can be attached to the axle in an electrically insulated manner. For example, an electrically insulating material can be arranged between the axle and the electrically conductive parts of the rotary contact bridge.The shaft can, in particular, protrude into the switching chamber through an opening in the switching chamber. In particular, the switching chamber can have a switching chamber base with an opening through which the shaft protrudes. The drive unit is preferably arranged outside the switching chamber and is intended and configured to rotate the shaft and thus the rotary contact bridge connected to the shaft. The drive unit and at least part of the shaft or even the entire shaft can thus form the drive system for rotating the rotary contact bridge.

[0015] For example, the drive unit can have a stepper motor that can cause rotation through a defined angle in incremental steps. Furthermore, the drive unit can have a magnetic drive that has a rotatable magnet armature that can be rotated by a magnetic circuit to cause the switching processes described above. For this purpose, the magnetic circuit can have a yoke. The rotatable magnet armature can be connected to the axle. For this purpose, the magnet armature can have a magnetic rotating core or be designed as a magnetic rotating core that can be attached to an end of the axle opposite the rotating contact bridge and that is part of the magnetic circuit. A coil that can be connected to a control circuit can generate a magnetic field in the magnetic circuit that rotates the magnet armature.

[0016] The drive unit can, for example, switch the switching device from the second to the first switching state. The rotary movement of the rotary contact bridge for switching from the first to the second switching state can also be effected by the drive unit or, preferably, alternatively or additionally, by a return spring. This ensures that when the control current for switching the switching device to the first switching state is lost, the switching device automatically switches to the second switching state, thus interrupting the load circuit.

[0017] According to a further embodiment, the drive system continues to rotate by a predetermined angle after reaching the first switching state. This means that the drive unit or the drive unit and at least part of the axle or also the drive unit and the axle can continue to rotate by a predetermined angle upon switching to the first switching state after reaching the first switching state, i.e., when the electrically conductive element of the rotary contact bridge is in galvanically conductive contact with the stationary contacts. The predetermined angle can particularly preferably be greater than or equal to 1° and less than or equal to 15°. For example, the rotary contact bridge can be attached to the axle with appropriate rotational play or an elastic fastening, so that the axle can rotate further than the rotary contact bridge. In other words, the drive system can "overrotate" upon switching to the first state.This makes it possible for the drive system, i.e., the drive unit or the drive unit and at least part of the axle, or even the drive unit and the axle, to already perform a rotary movement upon switching to the second operating state, before the rotary contact bridge and, in particular, the electrically conductive element of the rotary contact bridge begins to rotate. This allows the drive system to gain speed and generate an angular momentum, which allows the stationary contacts to be electrically separated from one another more quickly after this angular momentum is transferred to the rotary contact bridge.

[0018] The axis can preferably comprise or be made of stainless steel. The switching chamber, in particular the switching chamber wall and / or the switching chamber floor, can preferably comprise or be made of a metal oxide ceramic such as Al2O3 or a plastic, at least in part. Plastics with sufficient temperature resistance are particularly suitable. For example, the switching chamber can comprise polyetheretherketone (PEEK), a polyethylene (PE), and / or glass-filled polybutylene terephthalate (PBT) as the plastic. Furthermore, the switching chamber can also at least in part be made of a polyoxymethylene (POM), in particular with the structure (CH2O). n , have.

[0019] According to a further embodiment, the contacts are arranged in a gas atmosphere. This can mean, in particular, that the rotary contact bridge is arranged entirely in the gas atmosphere and that, furthermore, at least a part of the at least one fixed contact, for example the contact region of the at least one fixed contact, is arranged in the gas atmosphere. For this purpose, the switching device can have a gas-tight region in which the gas atmosphere is kept hermetically sealed from the environment and in which the described components can be arranged. The gas-tight region can be formed by parts of the housing and / or by additional walls and / or by components within the housing. For example, the gas-tight region can be formed by parts of the switching chamber wall and, if appropriate, a yoke, as well as in combination with additional wall parts, for example with or made of pure iron, aluminum, or stainless steel.In particular, the switching chamber can be arranged in the gas-tight region of the switching device or form part of it. Furthermore, the drive unit can also be arranged partially or preferably entirely within the gas-tight region. Accordingly, the switching device can particularly preferably be a gas-filled switching device, such as a gas-filled contactor. By increasing the arc voltage, the gas atmosphere can in particular promote the extinguishing of arcs that can arise between the contacts during switching operations. The gas of the gas atmosphere can preferably contain H2 and particularly preferably a proportion of at least 50% H2. In addition to hydrogen, the gas can contain an inert gas, particularly preferably N2 and / or one or more noble gases. Furthermore, the gas, i.e. at least part of the gas atmosphere, can in particular be located in the switching chamber.

[0020] According to a further embodiment, the switching chamber has a cylindrical switching chamber wall, and the fixed contacts protrude through the switching chamber wall into the switching chamber. The fact that the switching chamber wall is cylindrical can mean, in particular, that the shape of the switching chamber wall has a cylindrical shell shape or is at least derived from a cylindrical shell shape, wherein the cylindrical shell has a circular cross-sectional area. In particular, the cylindrical shell shape has a cylinder axis that coincides with the axis of rotation. The switching chamber wall can additionally have indentations and / or bulges in or on an inner wall facing the rotary contact bridge and / or an outer wall facing away from the inner wall.Particularly preferably, the fixed contacts in the switching chamber wall can be aligned radially to the rotation axis, with two fixed contacts to be connected by the rotary contact bridge preferably being arranged opposite one another in the radial direction. The fixed contacts can each have a contact region with a contact surface facing the rotary contact bridge. At least some of the contact regions or at least some of the contact surface of each of the fixed contacts can protrude beyond the inner wall.

[0021] According to a further embodiment, each of the fixed contacts has a beveled contact surface facing the rotary contact bridge. A "beveled contact surface" can mean, in particular, that the contact surface is not arranged tangentially to the rotational movement of the rotary contact bridge and thus not tangentially to the inner wall of the switching chamber wall. The contact surfaces can be beveled on one or more sides. By beveling the contact surfaces, the mechanical contact with the rotary contact bridge can be improved. Furthermore, the contact surfaces can be beveled such that the contact surfaces counteract a rotational movement of the rotary contact bridge in one direction, so that the rotary contact bridge can be prevented from rotating beyond the first state when rotating from the second to the first state.

[0022] According to a further embodiment, the rotary contact bridge is spaced from the inner wall of the switching chamber wall. Particularly preferably, the rotary contact bridge is spaced from the inner wall of the switching chamber wall in every switching state, as well as during switching from the first to the second switching state and vice versa. For example, the inner wall of the switching chamber wall can have a diameter that is greater than the largest dimension of the rotary contact bridge perpendicular to the axis of rotation. For example, the inner wall of the switching chamber wall can have an enlarged diameter, at least in the region of the rotary contact bridge. Particularly preferably, the fixed contacts can be arranged in a groove in the inner wall that at least partially surrounds the rotary contact bridge. A gap can therefore be present between the rotary contact bridge and the inner wall of the switching chamber wall, at least in the radial direction.The narrower the gap, the easier it is to extinguish switching arcs that occur during switching, as there is less space for the switching arcs to spread.

[0023] In particular, the rotary contact bridge has spring-mounted contact pieces. In particular, the rotary contact bridge can have a central part attached to the axis. The contact pieces can be arranged on this central part with spring elements arranged between them. The central part, the spring elements, and the contact pieces can be formed as a single piece or from separately manufactured parts that are joined together to form the electrically conductive element. When the contact surfaces of the fixed contacts make contact when switching to the first switching state, the spring-mounted contact pieces can be pressed in the direction of the rotary axis, so that an increased contact pressure can be achieved by the spring elements. This can enable secure and permanent contact between the contact pieces and the fixed contacts in the first switching state.When switching from the first to the second switching state, the spring elements can relax again and push the contact pieces radially away from the center section. Particularly preferably, the contact pieces still maintain a distance from the inner wall of the switching chamber wall when the spring elements are relaxed.

[0024] According to a further embodiment, the rotary contact bridge has at least one insulator element which has or is made of an electrically insulating material. The electrically conductive element of the rotary contact bridge is preferably at least partially surrounded by the insulator element. For example, the insulator element can form part of a disk. There can also be multiple insulator elements. The rotary contact bridge can thus, for example, be formed essentially by the electrically conductive element and the at least one insulator element as a disk, wherein the contact pieces can protrude from the disk in the radial direction. Particularly preferably, the electrically conductive element is enclosed by the at least one insulator element except for some of the contact pieces, so that the electrically conductive element is embedded in the at least one insulator element.

[0025] According to a further embodiment, the switching device has two secondary contacts in the form of auxiliary contacts, which are electrically connected to one another in the second switching state by the rotary contact bridge. In the first switching state, however, the auxiliary contacts are electrically separated from one another. For example, by measuring the electrical resistance, a voltage drop, or an auxiliary current flow through the auxiliary contacts, it can be determined whether the switching device is in the second switching state or whether, for example, the contacts have become stuck and the rotary contact bridge can no longer rotate from the first to the second state.Furthermore, it may also be possible for a further electrically conductive element, which can also be referred to as an electrically conductive auxiliary element, to be present in the rotary contact bridge, by means of which the auxiliary contacts are electrically conductively connected to one another in either the first or the second switching state. For example, the auxiliary contacts can thereby be switched at the same time as the fixed contacts and thus in parallel with them. The features described above and below for the electrically conductive element can also apply to the electrically conductive auxiliary element. Furthermore, features described above and below for the fixed contacts can also apply to the auxiliary contacts. In particular, however, the auxiliary contacts can be dimensioned smaller than the fixed contacts, since the auxiliary contacts do not have to have the same current-carrying capacity as the fixed contacts.

[0026] According to a further embodiment, the switching device has a magnet, in particular a permanent magnet, above each of the fixed contacts in a direction parallel to the axis of rotation. The magnets are preferably arranged outside the switching chamber, for example on or at the outside of the switching chamber. The magnets, which act as so-called quenching magnets, can generate a magnetic field in the region of the fixed contacts. Due to the Lorentz force, this field leads to an extension of switching arcs and to the expulsion of the switching arcs from the areas between the contact surfaces of the fixed contacts and the contact pieces of the rotating contact bridge, which can facilitate the quenching of the switching arcs.

[0027] According to a further embodiment, the switching device comprises a plurality of pairs of fixed contacts, each of which can be interconnected by an associated electrically conductive element in the rotary contact bridge. This makes it possible to simultaneously interconnect or electrically separate several pairs of fixed contacts with a single rotational movement of the rotary contact bridge. If the rotary contact bridge comprises several electrically conductive elements, these are preferably arranged in the rotary contact bridge in such a way that they are electrically insulated from one another by one or more insulator elements.

[0028] In the switching device described here, the switching process is performed by means of a rotational movement instead of the linear movement typical of the prior art. This can be achieved, for example, by a stepper motor or a magnetic drive with a magnetic circuit and coil drive as the drive unit. In the case of a stepper motor as the drive unit, this can have a high torque, so that even large restoring forces can be overcome, for example, by a strong return spring. A magnetic drive, for example, can be more cost-effective.

[0029] In particular, it has been shown that a switching device described here in the form of a gas-filled power contactor with a combination of the rotary contact bridge and a gas filling, i.e., a gas atmosphere that promotes arc quenching, is advantageous in a switching chamber, wherein the switching chamber is made of or made of a ceramic material or a previously described plastic material. Particularly preferably, the switching device additionally comprises quenching magnets.

[0030] The rotary contact bridge can particularly preferably be designed such that the rotary contact bridge fills the switching chamber as completely as possible, so that only the narrowest possible gap exists between the inner wall of the switching chamber wall and the rotary contact bridge. Together with a wide opening travel determined by the angle of rotation between the first and second switching states, this can promote rapid extinguishing of switching arcs. With regard to typical sizes of power contactors, for example, with a rotation through an angle of 90°, the distance between the electrically conductive parts can be increased from approximately 1 mm per fixed contact to, for example, approximately 10 mm or even several tens of mm, for example more than 20 mm. This makes it possible to achieve very high insulation voltages.

[0031] The switching device described here also has the advantage that abrasion or deposits resulting from disconnection processes at high voltage and high current are deposited on opposite sides of the housing. The reduction in insulation resistance over the service life is therefore lower than with conventional contactors with a linear movement. The arrangement of the contacts with the main terminals, i.e. the fixed contacts, in a radial direction on the sides prevents contact levitation, as there is no change in the direction of current flow when passing through the switch. The design of the switching device described here is also largely immune to external vibration influences. In particular, there is no axis in which excitation could lead to unintentional opening or closing of the contacts.Parallel contacts, such as auxiliary contacts or additional fixed contacts, can be easily integrated and connected in parallel or alternately via additional electrically conductive elements on the rotary contact bridge. Soldering or other mounting options can also be implemented, particularly in the switching chamber wall, which is possible due to the larger spacing of the fixed contacts. By separating the switching arcs on opposite sides in the radial direction, a collision of the arcs is very unlikely. If magnets are also used, as described above, the base points can always be deflected against the direction of rotation. This significantly promotes arc interruption.

[0032] Further advantages, advantageous embodiments and further developments emerge from the exemplary embodiments described below in conjunction with the figures.

[0033] They show: Fig. 1A to 1I are schematic representations of a switching device according to an embodiment, Fig. 2 a schematic representation of a drive unit for a switching device according to an embodiment and Fig. 3A and Fig. 3B schematic representations of a part of a switching device according to another embodiment.

[0034] In the exemplary embodiments and figures, identical, similar, or similarly functioning elements may be provided with the same reference numerals. The illustrated elements and their relative sizes are not to be considered to scale; rather, individual elements, such as layers, components, structural elements, and regions, may be exaggerated for clarity and / or clarity.

[0035] In the Fig. 1A to 1I show an embodiment of a switching device 100, which can be used, for example, to switch strong electrical currents and / or high electrical voltages of a load circuit connectable to the switching device 100 and which can be a relay or contactor, in particular a power contactor. Fig. 1A and Fig. 1B are three-dimensional sectional views of the switching device 100, while in the Fig. 1C and Fig. 1D external views of the switching device 100 are shown in a top view and a side view. Fig. The section shown in Figure 1A corresponds to the section shown in Fig. 1C indicated section plane AA, while in Fig. 1B shown section of the Fig. 1C shown section plane BB. In the Fig. 1E and Fig. 1F are sectional views of the switching device 100 along the Fig. 1D and thus with a view along the rotation axis 99 indicated in Figures 1a, 1B and 1G, wherein the switching device 100 in Fig. 1E in a first switching state and in Fig. 1F, as well as in the Fig. 1A, Fig. 1B and Fig. 1G, in a second switching state. In Fig. 1G shows a sectional view along section plane BB of the gas-tight region 16 of the switching device 100, which essentially corresponds to the switching device 100 without the housing 1. In the Fig. 1H and Fig. 1I shows three-dimensional views of essentially the gas-tight area 16 and thus the switching device 100 without the housing 1 as well as an external view of the switching device 100. The following description also refers to the Fig. 1A to 1I. The geometries shown are only exemplary and not limiting and may also be designed alternatively.

[0036] The switching device 100 has two fixed contacts 2, 3 and a rotary contact bridge 4. A load circuit can be connected to the fixed contacts 2, 3, which are arranged separately from one another in the switching device 100. The fixed contacts 2, 3, together with the rotary contact bridge 4 as a rotatable contact, form the switching contacts.

[0037] The switching contacts and the other components described below are arranged in a housing 1. The housing 1 primarily serves as contact protection for the components arranged inside and comprises or is made of a plastic, for example PBT or glass-filled PBT.

[0038] The rotary contact bridge 4 forms a contact which is rotatable about a rotation axis 99 and is rotatable in the switching device 100 such that the rotary contact bridge 4 can be switched between the first switching state, which is Fig. 1E, and the second switching state shown in Fig. 1F as well as in the Fig. 1A, Fig. 1B and Fig. 1G. Thus, the switching operation of the switching device 100 is essentially carried out by the rotary contact bridge 4. In the first switching state, which is a switched-on state of the switching device 100, the fixed contacts 2, 3 are electrically conductively connected to one another by the rotary contact bridge 4, so that the current of a connected load circuit can flow through the switching device 100 and in particular through the fixed contacts 2, 3 and the rotary contact bridge 4. In the second switching state, which is a non-switching state of the switching device 100 and in which the rotary contact bridge is rotated by an angle about the rotation axis 99 relative to the first switching state, the fixed contacts 2, 3 are electrically separated from one another. As shown in Fig. 1E, the fixed contacts 2, 3 in the first switching state are in mechanical contact with the rotary contact bridge 4 and are thus galvanically connected to it, while the fixed contacts 2, 3 in the second switching state are mechanically and thus also galvanically separated from the rotary contact bridge 4. As shown, for example, a change can be made between the first and second switching states by rotating the rotary contact bridge 4 by an angle of 90°. Alternatively, other configurations are also possible in which a change can be made between the switching states by rotating the rotary contact bridge 4 by an angle of greater than or equal to 10° and less than or equal to 170°, such as 10°, 15°, 30°, 45° or multiples thereof.

[0039] The rotary contact bridge 4 has an electrically conductive element 40 which, in the first switching state, contacts the fixed contacts 2, 3 and establishes an electrical connection between the fixed contacts 2, 3. The electrically conductive element 40 has a contact piece 41 on a side of the rotary contact bridge 4 facing away from the rotation axis 99 in the radial direction for contacting each of the fixed contacts 2, 3. In the first switching state, each of the contact pieces 41 of the electrically conductive element 40 is in mechanical contact with a contact surface 21, 31 of a contact region 20, 30 of a fixed contact 2, 3. In the second switching state, the rotary contact bridge 4 is rotated relative to the first switching state such that the contact pieces 41 are galvanically separated from the fixed contacts 2, 3.

[0040] The switching device 100 further comprises a drive unit 5, by means of which the rotary contact bridge 4 can be rotated for switching, i.e., for changing the switching state. In the illustrated embodiment, the drive unit 5 comprises a motor, in particular a stepper motor, or is designed as such. By means of a stepper motor, a rotation by a defined angle can be effected in incremental steps and a high torque can be provided. Alternatively, the drive unit can comprise a magnetic drive, as described further below in connection with the Fig. 2. To control the drive unit, a connection element 6 and supply lines may be provided, for example, as shown.

[0041] Furthermore, the switching device 100 has an axis 7, which is made of or comprises stainless steel, for example, and which is connected at one end to the rotary contact bridge 4 such that the rotary contact bridge 4 can be rotated by means of the axis 7. At the opposite end, the axis 7 is connected to the drive unit 5 so that the drive unit 5 can rotate the rotary contact bridge 4. The axis 7 thus defines the axis of rotation 99 of the rotary contact bridge 4. The rotary contact bridge 4 is particularly preferably fastened to the axis 7. In particular, the rotary contact bridge 4 can be fastened to the axis 7 in an electrically insulated manner. As shown, an electrically insulating material 8, in particular a plastic such as PBT or POM, can be arranged between the axis 7 and the rotary contact bridge 4, in particular at least between the axis 7 and electrically conductive parts of the rotary contact bridge 4.The rotary contact bridge 4 can be attached to the axis 7, for example, by means of a pin 9, as shown. The electrically insulating material 8 can be additionally secured to the axis 7, for example, by a snap ring 87, as shown.

[0042] The drive unit 5 can switch the switching device 100, for example, from the second to the first switching state. The rotary movement of the rotary contact bridge 4 for switching from the first to the second switching state can also be effected by the drive unit 5 or, preferably alternatively or additionally, by a return spring 10. The return spring 10 can ensure that, when a control current for switching the switching device 100 is lost, the switching device 100 automatically switches from the first switching state to the second switching state, thus interrupting the load circuit.

[0043] The drive unit 5 can form a drive system on its own or with part of the axis 7 or with the entire axis 7, which continues to rotate by a predetermined angle after reaching the first switching state. This means that the drive unit 5 or the drive unit 5 and at least part of the axis 7 or also the drive unit 5 and the axis 7 can continue to rotate by a predetermined angle when switching to the first switching state after reaching the first switching state, while the rotary contact bridge 4 is no longer rotated. The predetermined angle can particularly preferably be greater than or equal to 1° and less than or equal to 15°. For example, the attachment of the rotary contact bridge 4 to the axis 7 can be designed with a corresponding play or can be elastic. For example, the pinning 9 can be arranged with a play on the axis 7 and / or the rotary contact bridge 4.Furthermore, it may also be possible for the pinning 9 to comprise an elastic material. By continuing to rotate the drive system, it can be achieved that the drive system can already perform a rotational movement at the beginning of switching from the first to the second operating state, before the rotary contact bridge 4 and in particular the electrically conductive element 40 of the rotary contact bridge 4 begins to rotate. This allows the drive system to gain speed and generate an angular momentum, which can ensure that the electrically conductive connection between the fixed contacts 2, 3 can be severed more quickly after this angular momentum has been transmitted to the rotary contact bridge 4.

[0044] The switching device 100 further comprises a switching chamber 11 in which the rotary contact bridge 4 and the stationary contacts 2, 3 are arranged. As described above in the general section, the stationary contacts 2, 3 protrude through the housing 1 and a switching chamber wall 12 into the switching chamber 11. This can mean, in particular, that at least some of the contact regions 20, 30 or at least some of the contact surfaces 21, 31 of each of the stationary contacts 2, 3 can protrude beyond an inner wall of the switching chamber wall 12 facing the rotary contact bridge 4. In particular, the switching chamber 11 comprises a cylindrical switching chamber wall 12. As shown, the stationary contacts 2, 3 are particularly preferably aligned radially to the rotation axis 99 in the switching chamber wall 12 and are preferably positioned opposite one another in the radial direction.

[0045] The switching chamber 11 further comprises a switching chamber base 13 having an opening through which the axis 7 extends. The drive unit 5 is arranged outside the switching chamber 11. The switching chamber 11, i.e. in particular the switching chamber wall 12 and / or the switching chamber base 13, can preferably comprise or be made at least partially of a metal oxide ceramic such as Al2O3 or a plastic such as PEEK, PE, glass-filled PBT, or POM. The switching chamber wall 12 and the switching chamber base 13 can also be made of different materials. For example, the switching chamber wall 12 is made of a ceramic material, while the switching chamber base 13 is made of a plastic.

[0046] The drive unit 5 is arranged in a pot made of a gas-tight wall 14 below the switching chamber 11. In the illustrated embodiment, a connecting plate 15 is arranged between the switching chamber 11 and the area below it with the drive unit 5, which, like the gas-tight wall 14, can be made of pure iron, aluminum, or stainless steel, for example. Fig. 1B and Fig. 1G, the connecting plate 15 can, for example, be screwed to the switching chamber 11, while the gas-tight wall 14 can be soldered or welded to the connecting plate 15.

[0047] The switching contacts of the switching device 100 are arranged in a gas atmosphere. In particular, the rotary contact bridge 4 is arranged entirely in the gas atmosphere, while some of the stationary contacts 2, 3, such as their contact areas 20, 30, are arranged in the gas atmosphere. For this purpose, the switching device 100 has a gas-tight region 16 in which the gas atmosphere is kept hermetically sealed from the environment and in which the described components can be arranged. In the exemplary embodiment shown, the gas-tight region 16 is formed by parts of the switching chamber wall 12, by the gas-tight walls 14, and by the connecting plate 15, wherein, in the exemplary embodiment shown, a gas-tight wall 14 is additionally provided between the switching chamber wall 12 and the connecting plate 15. This makes it possible to use a material that is not gas-tight as the switching chamber base 13.The switching device 100 is thus a gas-filled switching device, such as a gas-filled contactor. By increasing the arc voltage, the gas atmosphere can, in particular, promote the extinguishing of arcs that may occur between the contacts during switching operations. The gas of the gas atmosphere can preferably contain H2 and particularly preferably a proportion of at least 50% H2. In addition to hydrogen, the gas can contain an inert gas, particularly preferably N2 and / or one or more noble gases.

[0048] In the illustrated embodiment, the gas-tight region 16 is arranged in the housing 1 by means of damping elements 17. The damping elements 17 can be made of an elastic plastic, for example in the form of rubber buffers, and reduce the transmission of mechanical stresses, shocks, and vibrations acting on the housing 1 from the housing 1 to the gas-tight region 16 and thus in particular to the switching chamber 11.

[0049] As in the Fig. 1E and Fig. 1F, the fixed contacts 2, 3 can each have a beveled contact surface 21, 31 facing the rotary contact bridge 4, which is not arranged tangentially to the rotational movement of the rotary contact bridge 4 and thus not tangentially to the inner wall of the switching chamber wall 12. The contact surfaces 21, 31 can be beveled on one side as shown or alternatively on multiple sides. By beveling the contact surfaces 21, 31, the mechanical contact with the rotary contact bridge 4 and in particular with the contact pieces 41 can be improved. Furthermore, the contact surfaces 21, 31 can be beveled such that the contact surfaces 21, 31 counteract an undesired rotational movement of the rotary contact bridge 4 in one direction, so that the rotary contact bridge 4 can be prevented from rotating beyond the first switching state when rotating from the second to the first switching state.

[0050] The contact pieces 41 of the rotary contact bridge 4 are particularly preferably spring-mounted. For this purpose, the rotary contact bridge 4 has a central part 42 fastened to the axis 7, on which the contact pieces 41 are arranged with spring elements 43 arranged therebetween. The contact pieces 41, the central part 42, and the spring elements 43 essentially form the electrically conductive element 40 and can be formed integrally or from separately manufactured parts that are joined together to form the electrically conductive element 40, for example, by means of soldering, welding, or mechanical joining techniques. As described in the general section, the spring-mounted mounting of the contact pieces 41 in the first switching state allows increased contact pressure to be exerted on the contact surfaces 21, 31, thus ensuring reliable mechanical contact.

[0051] Preferably, at least the contact pieces 41 and particularly preferably the rotary contact bridge 4 are spaced apart from the inner wall of the switching chamber wall 12. Preferably, at least the contact pieces 41 and particularly preferably the rotary contact bridge 4 are spaced apart from the inner wall of the switching chamber wall 12 in every state and also during the switching operations. For example, the inner wall of the switching chamber wall 12, as shown in the Fig. 1A, Fig. 1B, Fig. 1E, Fig. 1F and Fig. 1G, have a diameter that is larger than the largest dimension of the rotary contact bridge 4 perpendicular to the axis of rotation 99. A gap is thus present in the radial direction between the rotary contact bridge 4 and the inner wall of the switching chamber wall 12. The narrower the gap, the easier it is to extinguish switching arcs that occur during switching, since there is less space for the switching arcs to spread. In particular, it is advantageous if the switching chamber 11 is filled with as much electrically insulating material as possible. In the exemplary embodiment shown, the rotary contact bridge 4 therefore has at least one insulator element 44 that has or is made of an electrically insulating material. For example, PBT or POM can be used for this purpose. The electrically conductive element 40 is preferably at least partially surrounded by the insulator element 44.As shown, the rotary contact bridge 4 can be formed essentially as a disk by the electrically conductive element 40 and the at least one insulator element 44, wherein the contact pieces 41 can protrude radially from the insulator element 44. Particularly preferably, the electrically conductive element 40, with the exception of a portion of the contact pieces 41, is enclosed by the at least one insulator element 44, so that the electrically conductive element 40 is embedded in the at least one insulator element 44. As an alternative to the arrangement shown in FIG. Fig. 1E and Fig. 1F, the insulator material 44 can also have recesses, as indicated by the dashed lines. The spring elements 43 and the contact pieces 41 can be arranged in corresponding pockets in the insulator element 44, which provide sufficient space for the spring function.

[0052] Furthermore, the switching device 100 can, as shown, have secondary contacts in the form of auxiliary contacts 18, which are electrically connected to one another in the second switching state by the rotary contact bridge 4. In the first switching state, however, the auxiliary contacts 18 are electrically separated from one another. By measuring the electrical resistance, a voltage drop, or an auxiliary current flow at the auxiliary contacts 18, it can be determined whether the switching device 100 is in the second switching state or whether, for example, the switching contacts have become stuck and the rotary contact bridge 4 can no longer rotate from the first to the second switching state. Alternatively, it may also be possible for a further electrically conductive element in the form of an electrically conductive auxiliary element to be present in the rotary contact bridge 4, by means of which the auxiliary contacts are electrically connected to one another in either the first or second switching state.

[0053] The control of the drive unit 5 and, if necessary, the contacting of the auxiliary contacts 18 from the outside can be carried out, for example, by means of a connection element in the housing 1. In Fig. 1I such a connection element is indicated on the outer surface of the housing 1.

[0054] In the illustrated embodiment, the switching device 100 further comprises a magnet 19, in particular a permanent magnet, above each of the fixed contacts 2, 3 in a direction parallel to the rotation axis 99. The magnets 19 are preferably arranged outside the switching chamber 11, for example, on or at the outside of the switching chamber 11. The magnets, which act as so-called quenching magnets, can generate a magnetic field in the area of the fixed contacts 2, 3, which can facilitate the quenching of the switching arcs.

[0055] The switching device 100 does not necessarily have to include all the elements included in the illustrated embodiment, such as spring elements, electrically insulating materials, magnets, damping elements, or auxiliary contacts. Furthermore, the switching device 100 can include a plurality of pairs of fixed contacts, each of which can be interconnected by an associated electrically conductive element in the rotary contact bridge 4.

[0056] In Fig. 2 shows an embodiment of a drive unit 5, which is designed as a magnetic drive that can be used as an alternative to a stepper motor described in connection with the previous embodiment. The magnetic drive has a rotatable magnetic armature 50 that can be rotated through a magnetic circuit in order to effect the switching processes described above. For this purpose, the magnetic circuit has a yoke 51. The magnetic armature 50 can have a magnetic rotating core or be designed as such, which is attached to an end of the axle opposite the rotating contact bridge and which is part of the magnetic circuit. The rotatable magnetic armature 50 is thus connected to the rotating contact bridge via the axle. The yoke 51 and / or the magnetic armature 50 can preferably comprise or be made of pure iron or a lightly doped iron alloy.A coil 52, which can be connected to a control circuit, can generate a magnetic field in the magnetic circuit, indicated by the dashed arrows, which causes a rotation 53 of the magnetic armature 51 and thus also of the rotary contact bridge. The reverse rotation can be achieved, for example, by the previously described return spring.

[0057] In the Fig. 3A and Fig. 3B shows a part of the switching device 100 according to a further embodiment. For the sake of clarity, Fig. 3A and Fig. 3B only a part of the switching chamber wall 12 and a contact piece 41 in the first switching state in contact with the contact surface 21 of a fixed contact 2 ( Fig. 3A) and in the second switching state ( Fig.3B). The switching chamber wall 12 has an inner wall 120 facing the rotary contact bridge, which has an enlarged diameter at least in the region of the rotary contact bridge. As can be seen, the fixed contacts can be arranged in a groove 121 in the inner wall 120 that at least partially surrounds the rotary contact bridge.

[0058] The features and exemplary embodiments described in conjunction with the figures can be combined with one another according to further exemplary embodiments, even if not all combinations are explicitly described. Furthermore, the exemplary embodiments described in conjunction with the figures can alternatively or additionally comprise further features according to the description in the general part.

[0059] The invention is not limited to the embodiments by the description. Rather, the invention encompasses any novel feature and any combination of features, including, in particular, any combination of features in the patent claims, even if this feature or combination itself is not explicitly stated in the patent claims or embodiments. List of reference symbols 1 housing 2, 3 fixed contact 4 rotary contact bridge 5 Drive unit 6 connecting element 7 Axis 8 electrically insulating material 9 Foundation 10 Return spring 11 Switching chamber 12 Switching chamber wall 13 Switching chamber base 14 gas-tight wall 15 Connecting plate 16 gas-tight area 17 Damping element 18 Auxiliary contact 19 Magnet 20 Contact area 21 Contact surface 30 Contact area 31 Contact surface 40 electrically conductive element 41 Contact piece 42 Middle section 43 Spring element 44 Insulator element 50 magnet armatures 51 yoke 52 coil 53 rotation 99 axis of rotation 100 switching device 120 interior wall 121 gutter

Claims

[1] Switching device (100) comprising two fixed contacts (2, 3) and a rotary contact bridge (4) in a switching chamber (11) in a gas-tight area (16) containing H2, wherein - the rotary contact bridge is rotatable about a rotation axis (99), - in a first switching state, the fixed contacts are electrically connected by the rotary contact bridge, - in a second switching state, the rotary contact bridge is rotated around the axis of rotation relative to the first switching state and the fixed contacts are electrically separated from each other, - the rotary contact bridge has an electrically conductive element (40) which, for contacting each of the fixed contacts, has a contact piece (41) on a side facing away from the axis of rotation in the radial direction, and the contact pieces are spring-mounted. [2] Switching device according to claim 1, wherein the switching chamber has a cylindrical switching chamber wall (12) and the fixed contacts protrude through the switching chamber wall into the switching chamber. [3] Switching device according to claim 2, wherein the switching chamber wall has an inner wall (120) facing the rotary contact bridge and the rotary contact bridge is spaced from the inner wall. [4] Switching device according to one of the preceding claims, wherein the rotary contact bridge has an insulator element (44) and the electrically conductive element is at least partially surrounded by the insulator element. [5] Switching device according to claim 4, wherein the insulator element forms part of a disc. [6] Switching device according to one of the preceding claims, wherein the rotary contact bridge is attached to an axis (7) in an electrically insulated manner. [7] Switching device according to one of the preceding claims, wherein each of the fixed contacts has a bevelled contact surface (21, 31) facing the rotary contact bridge. [8] Switching device according to one of the preceding claims, wherein the switching device has two auxiliary contacts (18) which are electrically connected to one another in the first or second switching state by the rotary contact bridge. [9] Switching device according to one of the preceding claims, wherein a magnet (19) is arranged above each of the fixed contacts in a direction parallel to the axis of rotation. [10] Switching device according to one of the preceding claims, further comprising a drive unit (5) by means of which the rotary contact bridge can be rotated to change the switching state. [11] Switching device according to the preceding claim, wherein the drive unit can continue to rotate by an angle of greater than or equal to 1° and less than or equal to 15° when switching to the first switching state after reaching the first switching state. [12] Switching device according to one of the preceding claims, wherein a rotation of the rotary contact bridge by an angle of greater than or equal to 10° and less than or equal to 170° enables switching between the first and second switching states. [13] Switching device according to one of the preceding claims, wherein the gas-tight region comprises H2 in a proportion of at least 50%.

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