Switching Device

Abstract

A switching device (100) is presented comprising at least two contacts (1) in a switching chamber (11), the at least two contacts including a fixed contact (2) and a movable contact (4), each of the contacts having a contact surface (21, 41) with at least one contact area (22, 42) on a contact side (20, 40), at least one of the contacts having at least one recess (50).

Description

[Technical Field]

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

[0002] The switching device is particularly designed as a current-driven, electromagnetically actuated, remotely operated switch. The switching device can be operated 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 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 driven motor vehicles, or in applications in the field of renewable energy.

[0004] In their role as safety components, contactors are usually used in combination with fuses between a battery, e.g., a lithium-ion battery, and an electric motor, and must be able to disconnect the power supply from the load in the event of a malfunction. Today, such systems typically operate at voltages of around 450 V. In the next generation of such systems, voltages can be up to 800 V. Furthermore, for example, in special applications, DC voltages of up to 1500 V are required.

[0005] The higher the applied voltage, the greater the challenges posed to the design of the contactor, which must interrupt large currents at the aforementioned high voltages in the event of a fault. Furthermore, it is required that the electrical parameters of the switching device continue to remain in their original or close to new state even after disconnection from the high load. This applies in particular to the contact resistance of the switching device, which is decisive for the heating of the entire device during normal operation and has a significant impact on its other performance and service life.

[0006] When the contacts of a switching device are broken under load, i.e., current, an arc occurs which can damage the surfaces of the contacts by melting, leading to the contact surfaces no longer being optimally aligned with one another and to an increased contact resistance when they are closed again.

[0007] To move the arc away from the contact area as quickly as possible and lengthen the arc path, so-called blowout magnets are usually used, which can deflect the arc in a specific direction depending on the direction of the current. For example, by appropriate switching chamber geometry and magnet placement, the arc can be deflected in a predetermined direction. Depending on the design, this can even be done independently of the current direction. In this way, the arc can be pushed to different sides of the contact or attached to different areas of the contact depending on the magnetic deflection configuration and, in some cases, the current direction. Therefore, undulations, which can lead to increased wear and contact resistance, can occur in different locations. For example, it is also known to design the moving contact short so that it covers only about half of the fixed contact. This design can result in the arc causing damage far outside the fixed contact, which is not in the actual contact area upon reclosure. However, this mechanism is ineffective against damage to the moving contact, which is likely to affect contact resistance upon reclosure. Another drawback is the reduced contact area, which can result in reduced heat transfer and increased local heating. Summary of the Invention [Problem to be solved by the invention]

[0008] At least one objective of certain embodiments is to provide a switching device. [Means for solving the problem]

[0009] This problem is solved by the subject matter of the independent claims. Advantageous embodiments and developments of the subject matter are set out in the dependent claims and will become apparent further from the following description and drawings.

[0010] According to at least one embodiment, the switching device comprises at least two contacts, which may also be referred to as first and second contacts, one of which is a fixed contact and the other of which is a movable contact. Correspondingly, 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.

[0011] According to at least one further embodiment, one of the contacts, hereinafter also referred to as the first contact, has at least one contact area. The first contact can be, for example, a fixed contact of the switching device. Alternatively, the first contact can be a movable contact of the switching device. The first contact is intended and arranged to form an electrical contact connection with a further contact, hereinafter also referred to as the second contact, when the contact is in a suitable position. In particular, the second contact can also have a contact surface with a contact area, such that the contact area of ​​the first contact and the contact area of ​​the second contact are in mechanical contact with each other and therefore electrically connected to each other when the contacts are in a suitable position relative to each other. In particular, each of the contacts can have a contact side with at least one contact area.

[0012] The movable contact is movable between a disconnected state and a connected state of the switching device such that in the disconnected state of the switching device it is separated from and thus electrically isolated from at least one fixed contact, and in the connected state it has mechanical contact with and thus is electrically connected to at least one fixed contact. The mechanical contact between the movable contact and the fixed contact in the connected state may in particular be between a contact area of ​​the movable contact and a contact area of ​​the fixed contact. Particularly preferably, the switching device comprises at least two fixed contacts that are arranged separately from one another in the switching device and thus can be conductively connected to one another or electrically isolated from one another via the movable contact, depending on the state of the movable contact.

[0013] According to a further embodiment, the switching device comprises a housing in which the contacts, i.e., at least one movable contact and at least one fixed contact, or at least two fixed contacts, are arranged. The movable contacts may in particular be arranged completely within the housing. Arranging the fixed contacts within the housing may in particular mean that at least the contact areas of the fixed contacts, which are in mechanical contact with the movable contact in the connected state, are arranged within the housing. For connection of the conductors of the circuit to be switched by the switching device, the fixed contacts arranged within the housing may be electrically contactable from the outside, i.e., from outside the housing. For this purpose, parts of the fixed contacts arranged within the housing may protrude from the housing and may have the possibility of connection for the conductors outside the housing.

[0014] According to a further embodiment, the contacts of the switching device are arranged in a gas atmosphere in the housing. This can mean, in particular, that at least one moving contact is arranged completely in the gas atmosphere in the housing, and that at least a part of the fixed contact, for example the contact area of ​​the fixed contact, is also arranged in the gas atmosphere in the housing. Accordingly, the switching device can particularly preferably be a gas-filled switching device, for example a gas-filled contactor.

[0015] According to a further embodiment, the contacts, i.e., the entirety of at least one movable contact and at least a part of the fixed contact, are arranged in a switching chamber inside the housing, in which gas, i.e., at least a part of a gas atmosphere, is present. The gas may preferably contain at least 50% H2. In addition to hydrogen, the gas may contain an inert gas, particularly preferably N2 and / or one or more noble gases.

[0016] According to a further embodiment, at least one movable contact is movable by the magnetic armature. The magnetic armature may have, for this purpose, in particular, a shaft connected at one end to the movable contact so that the movable contact is movable by the shaft, i.e., so that it is also moved by the shaft when the shaft moves. The shaft may, in particular, protrude into the switching chamber through an opening in the switching chamber. The magnetic armature may be movable by the magnetic circuit to bring about the above-mentioned switching operation. For this purpose, the magnetic circuit may have a yoke having an opening through which the shaft of the magnetic armature protrudes. The shaft may preferably include or consist of special steel. The yoke may preferably include or consist of pure iron or a lightly doped iron alloy.

[0017] According to a further embodiment, each of the contacts of the switching device has a contact side on which at least one contact area is arranged. The contact area of ​​each of the contacts may be a part of the surface of the contact side of the associated contact, which is intended and arranged to come into mechanical contact with a further contact in the switched-on state of the switching device, in particular during normal functioning of the switching device. The surface with the contact area is here and below also referred to as contact surface, although it is not necessary that all areas of the contact surface are formed as contact areas.

[0018] In particular, the movable contact may have a contact surface having an elongated configuration, in particular a rectangular or rectangular-shaped configuration (e.g., a rectangular with chamfered or rounded corners). A portion of the surface of the contact side, i.e., a portion of the contact surface, may form a contact area. If the movable contact is intended and arranged to contact at least two fixed contacts, the contact surface may have at least two contact areas, which may be separated by one or more surface areas that do not form a contact area. At least one fixed contact may have a contact surface that has or approximates a round shape, such as a circle, and at least partially or preferably completely forms a contact area. For example, the contact area of ​​the fixed contact may constitute at least 70%, or at least 80%, or at least 90% of the contact surface.

[0019] In particular, the contact side of at least one movable contact may face at least one fixed contact, and the contact side of at least one fixed contact may face at least one movable contact. The contact side of the contact, i.e. in particular the contact surface, may preferably have a main extension plane along which the contact surface extends. The direction parallel to the contact side, and thus to the main extension plane of the contact side, may also be referred to here and below as the lateral direction. The direction perpendicular to the contact side, and thus to the main extension plane of the contact side, may also be referred to here and below as the vertical direction. The contact may be surrounded or bounded in the lateral direction by one or more outer surfaces.

[0020] For example, the contact area of ​​a contact may be a flat bearing surface of a contact surface. Additionally, the contact area may have or be a particular geometric shape, such as a ridge or depression, and / or a different material compared to other areas of the contact.

[0021] According to a further embodiment, at least one contact of the switching device has at least one recess on its contact side. This means that the contact surface does not extend laterally to the outer surface that bounds the contact, but is separated from the outer surface by, for example, a step or a bevel. The at least one contact having at least one recess may preferably be a movable contact. Alternatively or additionally, the fixed contact may also have at least one recess. The contact area of ​​the contact surface of the contact may directly adjoin the respective recess in one or more directions.

[0022] For example, the recess can be formed by a groove or a bevel, which is formed by the contact surface and the outer surface and extends between the contact surface and the outer surface along an imaginary edge that no longer exists due to the groove or bevel. The recess can form two outer edges, of which a first outer edge is adjacent to the contact surface and a second outer edge is adjacent to the outer surface. The first and second outer edges can be connected to each other via one or more recess surfaces.

[0023] The height of the recess, i.e., the vertical distance between the first and second outer edges, is hereinafter designated H. The width of the recess, i.e., the lateral distance between the first and second outer edges, is hereinafter designated B. The total thickness of the contact in the vertical direction is hereinafter designated D.

[0024] The recess may comprise or be formed by, for example, a notch ("rabbet"), a chamfer ("champer"), a fillet ("concave fillet"), or a combination thereof. The chamfer may be an external chamfer ("external chamfer") or an internal chamfer ("internal chamfer").

[0025] For example, the recess can be formed by an external chamfer, i.e., by a bevel in the region of the outer edge between the contact surface and the outer surface, which no longer exists as a bevel. In this case, the first and second outer edges are connected to each other by a planar recess surface oriented obliquely relative to the contact surface and the outer surface, which may subtend an angle of 10° to 80°, preferably 45°, with the main extension plane of the contact side, i.e., with the contact surface. The ratio B / H is preferably 0.2 to 5, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0026] Furthermore, the recess can be formed by a fillet, i.e., by a groove having a round cross section, in the region of the outer edge between the contact surface and the outer surface, which is no longer formed by a groove. In this case, the first and second outer edges are connected to each other via a curved recess surface, preferably having a cross section corresponding to the circular cross section. The fillet can have a radius R, and the ratio R / D is preferably 0.05 to 2. The ratio B / H is preferably 0.2 to 10, or 5 to 1, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0027] Furthermore, the recess can be formed by a step, such that a first recess surface adjoins the contact surface, forming a first outer edge with the contact surface at a first angle, and a second recess surface adjoins the outer surface, forming a second outer edge with the outer surface at a second angle. The first and second recess surfaces can sandwich a third angle. The first, second, and third angles can be the same or different and are each greater than or equal to 90° and less than 180°, preferably each 90°. Particularly preferably, the first recess surface can be at least partially or completely parallel to the outer surface. Furthermore, the second recess surface can be at least partially or completely parallel to the contact surface. When the first and second angles are each 90°, dimension H can correspond to the difference in vertical height between the second recess surface and the contact surface, and dimension B can correspond to the distance between the outer surface and the first side surface.

[0028] For example, the recessed portion may be Lovett or Lovett In this case, the transition between the first and second recess surfaces can be formed by an inner edge, and the third angle is preferably 90°. In this case, the first and second angles can preferably also each be 90°. The ratio B / H is preferably 0.2 to 5, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0029] Additionally, the recess may have an internal chamfer. In this case, the recess may have: Lovett and a chamfered portion. LovettIn contrast, the transition between the first and second recess surfaces is not formed by an inner edge but by a bevel in the form of an internal chamfer, so that a third recess surface is formed between the first and second recess surfaces. In this case, the first and second recess surfaces are connected to each other by a planar recess surface oriented at an angle relative to the first and second recess surfaces, which may subtend an angle of 10° to 80°, preferably 45°, with the main extension plane of the contact side, i.e., with the contact surface. The ratio B / H is preferably 0.2 to 5, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0030] Furthermore, the recessed portion is Lovett and a fillet. In other words, the transition from the first recess surface to the second recess surface may be formed by a curved recess surface, the cross section of which preferably corresponds to a circular cross section. The fillet may have a radius R, and the ratio R / D is preferably 0.05 to 2. The ratio B / H is preferably 0.2 to 10, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0031] According to a further embodiment, at least one contact of the switching device has recesses on its contact side in different regions, in particular in different lateral directions. The recesses may be separate from one another or merge with one another. Furthermore, for example, different or identical recesses may be present on different side surfaces, and thus on different outer surfaces of the contact. In this way, different shapes of recesses can be formed on different side surfaces. Furthermore, different contacts may also have different recesses.

[0032] According to a further embodiment, the contact surfaces of the fixed contacts extend beyond the contact surfaces of the movable contacts in the transverse direction and / or coincide with at least a portion of the movable contact. For example, the contact surfaces of the fixed contacts have a first width and the contact surfaces of the movable contacts have a second width, the first and second widths being measured along the same transverse direction, the first width being equal to or preferably greater than the second width. If the switching device comprises two fixed contacts that can be electrically connected to each other by a movable contact, the transverse direction along which the first and second widths are measured is preferably perpendicular to the connecting line between the center points of the contact surfaces of the two fixed contacts, in which case the first width of each of the fixed contacts is equal to or preferably greater than the second width. Particularly preferably, the contact surface of each of the fixed contacts extends beyond the contact surface of the movable contact in a transverse direction parallel to the connecting line between the center points of the contact surfaces of the two fixed contacts.

[0033] In particular, one or more recesses may be formed in the contact side of the movable contact in one or more areas where the contact surface of the fixed contact projects beyond the contact surface of the movable contact.

[0034] In the switching devices described herein, so-called sacrificial areas can be provided by the fixed contacts laterally protruding beyond the movable contact and / or by the presence of one or more recesses on the contact side of one or more contacts. Arcs occurring at the contact surface can easily jump onto the sacrificial area, and damage to the sacrificial area by the arc advantageously does not result in a deterioration of the contact resistance between the contact areas. This can be achieved by the arc moving along and down the described shape of the edge of the contact and therefore not being able to burn for long periods on the contact surface.

[0035] Further advantages, advantageous embodiments and developments will become apparent from the examples described below in conjunction with the drawings. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is a schematic diagram of an example of a switching device according to one embodiment; [Figure 2] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 3A] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 3B] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 4A] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 4B] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 5A] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 5B] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 5C] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6A] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6B] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6C] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6D] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6E] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6F] 4 is a schematic diagram of a part of a switching device according to a further embodiment; [Figure 6G] 4 is a schematic diagram of a part of a switching device according to a further embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0037] 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 relative to one another 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.

[0038] 1 shows an embodiment of a switching device 100, which can be used, for example, for switching high currents and / or high voltages and can be a relay or contactor, in particular a power contactor. A three-dimensional cross-sectional view along a vertical cutting plane is shown in FIG. 1. It should be understood that the illustrated geometry is merely exemplary and not limiting, and can be designed in other ways.

[0039] The switching device 100 includes contacts 1, also referred to below as switching contacts, in a housing (not shown). The housing primarily serves as contact protection for the components arranged inside and comprises or consists of a plastic, such as PBT or glass-fiber-filled PBT. In the illustrated embodiment, the switching device 100 includes, as contacts 1, two fixed contacts 2 and a movable contact 4 mounted on an insulator 3. The movable contact 4 is designed as a contact plate. The fixed contact 2, together with the movable contact 4, form a switching contact. Instead of the number of contacts shown, other numbers of contacts 1, i.e., other numbers of fixed and / or movable contacts, are also possible. The fixed and / or movable contacts 2 and / or 4 can comprise or consist of one or more high-melting-point metals, such as Cu, a Cu alloy, Wo, Ni, and / or Cr, or a mixture of the aforementioned materials, for example, a mixture of copper and at least one other metal, such as Wo, Ni, and / or Cr.

[0040] 1, the switching device 100 is shown in a switched-off state in which the movable contact 4 is separated from the fixed contact 2, and thus the contacts 2, 4 are electrically disconnected from each other. It should be understood that the illustrated embodiment of the switching contacts, and in particular their geometry, is purely exemplary and not limiting. Alternatively, the switching contacts can be designed in other ways.

[0041] The switching device 100 comprises a movable magnetic armature 5 which essentially performs the switching movement. The magnetic armature 5 comprises a magnetic core 6 which, for example, comprises or consists of a ferromagnetic material. The magnetic armature 5 further comprises a shaft 7 which runs through the magnetic core 6 and is rigidly connected to the magnetic core 6 at one axial end. At the axial end opposite the magnetic core 6, the magnetic armature 5 comprises a movable contact 4 which is also connected to the shaft 7. The shaft 7 may preferably comprise or be made of special steel.

[0042] To electrically insulate the movable contact 4 from the axis 7, an insulator 3, which may also be called a bridge insulator, is arranged between them. To mount the movable contact 4 on the insulator 3, the movable contact 4 can be inserted into the opening of the movable contact 4 in a position rotated around the axis 7. The shape of the opening of the movable contact 4 and the insulator 3 is selected so that when the movable contact 4 is rotated into the correct mounting position relative to the insulator 3, the movable contact 4 is locked upward in the insulator 3 so that it no longer slips off the insulator 3. For example, for this purpose, there may be a locking lug on the insulator 3 and a mating groove in the opening of the movable contact 4. At the same time, the opening of the movable contact 4 may be large enough that the movable contact 4, in the mounted state, can still be easily tilted relative to the axis 7 and moved along it, thereby compensating for any possible height differences. To help compensate for possible height differences and ensure sufficient mechanical contact between the fixed contact 2 and the contact bridge 4, a contact spring 34 is positioned below the movable contact 4, supported by the insulator 3 and exerting a force on the movable contact 4 in the direction of the fixed contact 2.

[0043] The magnetic core 6 is surrounded by a coil 8. A current in the coil 8, which can be externally connected via a control circuit, causes axial movement of the magnetic core 6, and thus of the entire magnetic armature 5, until the movable contact 4 comes into contact with the fixed contact 2. In the illustrated example, the magnetic armature moves upwards. In this way, the magnetic armature 5 moves from a first, or idle, position, which corresponds to a disconnected or non-connected state and thus a switched-off state, to a second, or active, or connected state and thus a switched-on state. In the active state, the contacts 1 are electrically connected to each other.

[0044] To guide the shaft 7 and thus the magnetic armature 5, the switching device 100 comprises a yoke 9, which may contain 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 through which the shaft 7 is guided. When the current in the coil 8 is interrupted, the magnetic armature 5 is again moved to the first position by one or more springs 10. Thus, in the illustrated example, the magnetic armature 5 moves downwards again. The switching device 100 is then again in its idle state with the contacts 1 open.

[0045] The direction of movement of the magnetic armature 5, and thus of the movable contact 4, is hereinafter also referred to as the vertical direction 91. The arrangement direction of the fixed contacts 2, which is perpendicular to the vertical direction 91, is hereinafter referred to as the longitudinal direction 92. The direction perpendicular to the vertical direction 91 and perpendicular to the longitudinal direction 92 is hereinafter referred to as the transverse direction 93. The directions 91, 92, and 93, which are valid regardless of the switching movement described, are shown in some figures to facilitate directional identification. The direction parallel to the plane spanned by the longitudinal direction 92 and the transverse direction 93, and therefore perpendicular to the vertical direction 91, is also called the transverse direction 90.

[0046] For example, when contact 1 opens, at least one arc may occur, potentially damaging the contact surfaces of contact 1. This could result in the contacts 1 becoming "stuck" together due to welding caused by the arc and no longer disconnecting from each other. In this case, switching device 100 remains switched on, even though the current in coil 8 must be switched off and the load circuit must be disconnected. To prevent such arcs from occurring, or at least to facilitate the extinguishing of any arcs that do occur, contact 1 can be placed in a gas atmosphere, so that switching device 100 can be designed as a gas-filled relay or contactor. For this purpose, contact 1 within switching chamber 11, formed by switching chamber wall 12 and switching chamber bottom 13, is located within hermetically sealed region 14, which may be part of switching chamber 11. Hermetically sealed region 14 completely surrounds magnetic armature 5 and contact 1, except for the portion of stationary contact 2 provided for external connection. The gas-tight region 14, and therefore also the internal space 15 of the switching chamber 11, is filled with gas. The gas-tight region 14 is substantially formed by the switching chamber 11, the yoke 9 and part of the additional wall. The gas that can be filled into the gas-tight region 14 through a gas filling nozzle during the manufacture of the switching device 100 can particularly preferably be a hydrogen-containing gas, for example containing 20% ​​or more H2 in an inert gas or 100% H2, since the hydrogen-containing gas can promote arc extinction.

[0047] The switching chamber wall 12 and the switching chamber bottom 13 can be made of or from a metal oxide, such as Al2O3, for example. Furthermore, plastics with a sufficiently high temperature stability, such as PEEK, PE and / or glass-fiber-filled PBT, are also suitable. Alternatively or additionally, the switching chamber 11 can be made at least in part of a metal oxide, in particular of the structure (CHO). nSuch plastics may be characterized by 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. The additional hydrogen can enhance arc extinction.

[0048] The above-described features of the switching device 100 should be understood to be purely exemplary and not limiting. For example, instead of the described embodiment as a gas-filled contactor, the switching device 100 can also be embodied without a gas filling. For example, the design of the contacts 1 described below, as also described in the general section, can provide one or more contacts 1 with so-called sacrificial areas, through which arcs can be moved away from the contact surface, thereby, among other things, reducing the tendency for contact welding caused by arcing. Therefore, the switching device 100 can also be embodied without a gas-tight area.

[0049] As can be seen in FIG. 1 , each of the contacts 1 has a respective contact side 20, 40, with the contact side 20 of each fixed contact 2 facing the movable contact 4 and the contact side 40 of the movable contact 4 facing each of the fixed contacts 2. In FIG. 2 , the fixed contacts 2 and the movable contact 4 are shown in cross section. The respective surfaces of the contact sides 20, 40 form contact surfaces 21, 41 of the fixed contacts 2 and the movable contact 4. The contact surfaces 21, 41 have contact areas 22, 42, respectively. The contact area 22, 42 of each of the contacts 1 can be a part of the respective contact surface 21, 41 that is intended and adapted to come into mechanical contact with a further contact, in particular in the switched-on state of the switching device 100 when the switching device 100 is functioning properly. In this case, it is not necessary for the entire area of ​​the contact surface to be formed as a contact area. Furthermore, the contact surfaces of the contacts may have more than one contact area, as is the case in the movable contact 4 in the illustrated switching device 100, which has contact areas 42 respectively assigned to each of the fixed contacts 2 on its contact surface 41, which are separated from each other by areas of the contact surface 41 that are not intended as contact areas. As can also be seen in Figure 1, the movable contact 4 may have a contact surface 41 with, for example, an elongated configuration with a main direction of extension in the longitudinal direction 92, in particular a rectangular or rectangular-shaped configuration (e.g. a rectangle with chamfered or rounded corners).

[0050] The contact surface 21 of each of the fixed contacts 2, in the illustrated embodiment, completely or at least substantially completely forms a respective contact area 22. For example, the contact area 22 of a fixed contact may constitute at least 70%, or at least 80%, or at least 90% of the contact surface 21. The contact surface 21, and thus the contact area 22, of the fixed contact 2 may preferably have or approximate a round, e.g., circular, shape. Correspondingly, the contact area 42 of the movable contact 4 may have or approximate a round shape.

[0051] For example, the contact area 22, 42 of the contact 1 may be a flat bearing surface of the contact surface 21, 41. Alternatively, the contact area 22, 42 may have or be a particular geometric shape, such as a ridge or depression, and / or a different material compared to other areas of the contact.

[0052] In a transverse direction 90, i.e., a longitudinal direction 92 that can be seen, for example, in Fig. 2, the contact point 1 is bounded by outer surfaces 23, 43. The distance between the outer surfaces 23, 43 that face each other in the transverse direction 90 can particularly preferably define the maximum extent of the contact point along this transverse direction 90.

[0053] Preferably, the entire contact surface 21 of the fixed contact 2 coincides with a portion of the contact surface 41 of the movable contact 4, or, as shown in the cross-sectional views of the switching device in Figures 3A and 3B, the contact surface 41 of the movable contact 4, and therefore the contact area 42, protrudes in multiple transverse directions 90. For example, the contact surface 21 of each of the fixed contacts 2 has a first width T2, and the contact surface 41 of the movable contact 4 has a second width T4, where the first and second widths T2, T4 are measured along the same transverse direction 90. In the illustrated embodiment of Figure 3A, the widths T2 and T4 are the widths of the contact surfaces 21, 41 in the transverse direction 93. The first width T2 of each of the contact surfaces 21 of the fixed contacts 2 is the same as the second width T4 of the contact surface 41 of the movable contact 4, or preferably, is greater than the second width T4 of the contact surface 41 of the movable contact 4, as shown in Figure 3A.

[0054] Furthermore, each contact surface 21 of the fixed contacts 2 preferably projects beyond the contact surface 41 of the movable contact 4 in the longitudinal direction 92 as well, as can be seen in the embodiment of Fig. 3B. Here, the outer surfaces 23, 43 of the contacts 1 may coincide in at least one lateral direction 90, as can also be seen in Fig. 3B. This may also be the case in the transverse direction 93. Furthermore, the outer surface 43 of the movable contact 4 may project beyond the outer surface 23 of the fixed contact 2 in the transverse direction 90, as can be seen, for example, in the transverse direction 93 in Fig. 3A. Alternatively, the reverse embodiment is also possible.

[0055] With regard to the above-described design of the contact 1, it may be particularly advantageous if at least one contact 1 of the switching device has at least one recess 50 on the contact side 20, 40. This means that the contact surface 21, 41 does not extend to the outer surface 23, 43 that laterally bounds the contact 1, but is separated from the outer surface 23, 43, for example, by a step or a slope. The at least one contact 1 having at least one recess 50 may preferably be a movable contact 4, as shown in the example of FIG. 4A. In this case, the recess 50 may be formed on the outer surface 43, on two outer surfaces 43 that face each other in the lateral direction 90, or on the entire outer surface 43, at least in the region of the contact area, as can be seen in FIG. 4A. Thus, the movable contact 4 shown in FIG. 4A has, for each of the contact areas 42 indicated by dashed lines, a special edge shape formed by the recess that is present on all three possible arc deflection sides.

[0056] Alternatively or additionally, the fixed contact 2 may also have at least one recess 50, as shown in the embodiment of Figure 4B. In the case of the fixed contact 2, the recess 50 may preferably be formed in the outer surface 23 in all lateral directions 90.

[0057] As can be seen in Figures 4A and 4B, the recess 50 can be formed by a groove or ramp that exists between the contact surface and the outer surface that does not have the groove or ramp and that extends between the contact surface 21, 41 and the outer surface 23, 43 along an imaginary edge that no longer exists due to the groove or ramp.

[0058] 5A to 5C and also 6A to 6G, purely by way of example, cross sections of contacts 1 are shown based on the movable contact 4, with recesses 50 on the outer surface 43 bounding the longitudinal direction 92. Various designs for the recesses are shown in FIGS. 6A to 6G. The following description of the various recess designs explicitly applies equally to the fixed contacts. Furthermore, the same or different recess designs are possible on different sides, i.e. in different lateral directions. For example, in the case of the movable contact 4, a first configuration of recesses can be provided on the outer surface in the transverse direction, and a second configuration of recesses different from the first configuration can be provided on the outer surface in the longitudinal direction.

[0059] As shown in Figures 5A-5C, recess 50 forms two outer edges 51, 52, with first outer edge 51 adjacent contact surface 41 and second outer edge 52 adjacent outer surface 43. The first and second outer edges 51, 52 may be connected to each other via one or more recess surfaces 53, 54. Figure 5B shows dimensions H and B of recess 50 and a thickness D of contact 1. Dimensions H and B shown in Figure 5B relate to outer edges 51, 52, which are always present regardless of the shape of recess 50, and therefore apply to all designs of recess 50 shown below. Although outer edges 51, 52 are shown as sharp edges, they may also be rounded or chamfered, in which case the dimensions presented below apply accordingly.

[0060] The height of the recess 50, i.e., the distance in the vertical direction 91 between the first outer edge 51 and the second outer edge 52, is hereinafter designated H. The width of the recess 50, i.e., the distance in the lateral direction 90 between the first outer edge 51 and the second outer edge 52, is hereinafter designated B. The total thickness of the contact in the vertical direction 91 is hereinafter designated D.

[0061] 5C, contact surface 41 subtends a first angle α1 with adjacent first recess surface 53 at first outer edge 51, while outer surface 43 subtends a second angle α2 with adjacent second recess surface 54 at second outer edge 52. First recess surface 53 and second recess surface 54 may subtend a third angle α3.

[0062] The recess may be, for example, a step, as shown in particular in FIGS. 5A and 5B ; Lovett Alternatively, the chamfer may have or be formed by a chamfer, a fillet, or a combination thereof. The chamfer may be an external chamfer or an internal chamfer.

[0063] The dimensions and angles described below apply to the dimensions and angles described in connection with Figures 5A-5C unless otherwise indicated in Figures 6A-6G described below.

[0064] 6A-6C, an embodiment of a contact 1 having a recess 50 is shown in cross section, which recess 50 Lovett The first, second, and third angles α1, α2, and α3 may be the same or different and are each equal to or greater than 90° and less than 180°, preferably 90°. Particularly preferably, the first recess surface 53 may be at least partially or completely parallel to the outer surface 43. Furthermore, the second recess surface 54 may be at least partially or completely parallel to the contact surface 41. When the first and second angles α1 and α2 are each 90°, the distance H may correspond to the difference in height between the second recess surface 54 and the contact surface 41 in the vertical direction. Meanwhile, the distance B corresponds to the distance in the lateral direction 90 between the outer surface 43 and the first recess side surface 53.

[0065] As shown in Figures 6A-6C Lovett In the figure, the transition between the first recess surface 53 and the second recess surface 54 is formed by an inner edge 55, and the third angle α3 at the inner edge 55 is preferably 90°. In this case, the first and second angles α1, α2 may preferably also each be 90°. The ratio B / H is preferably 0.2 or more and 5 or less, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and 0.8 or less, particularly preferably 0.1 or more and 0.5 or less. Figure 6A shows an example of a case where B / H=0.5. LovettIn this case, for example, B=0.5 mm and H=1 mm. FIG. 6B shows an example of a ratio B / H=2. Lovett In this case, for example, B=1 mm and H=0.5 mm. FIG. 6C shows an example of the case where B / H=1. Lovett In this case, for example, B=1 mm and H=1 mm.

[0066] As shown in Figure 6D, the recess 50 may have an internal chamfer. In this case, the recess 50 may have a Lovett As shown in Figures 6A to 6C, the recessed portion may be formed by a combination of a first recessed surface 53 and a second recessed surface 54. Lovett In contrast, the transition between the first and second recess surfaces 53, 54 is not formed by an inner edge but by a bevel in the form of an internal chamfer, resulting in a third recess surface 56 being formed between the first and second recess surfaces 53, 54. In this case, the first and second recess surfaces 53, 54 are connected to each other via a planar third recess surface 56 oriented obliquely relative to the first and second recess surfaces 53, 54, forming two inner edges 55. The third recess surface 56, together with the main extension plane of the contact surface 41, preferably defines an angle α4, which is therefore the angle of the internal chamfer, of 10° to 80°, particularly preferably 45°. The ratio B / H is preferably 0.2 to 5, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0067] Furthermore, as shown in FIG. 6E, the recess 50 can be formed by an external chamfer, i.e., by a bevel in the region of the outer edge that no longer exists between the contact surface 41 and the outer surface 43. In this case, the first and second outer edges 51, 52 are connected to one another by a planar recess surface 53 oriented obliquely with respect to the contact surface 41 and the outer surface 43, which may, together with the main extension plane of the contact surface 41, enclose an angle α4, i.e., a chamfer angle, of preferably between 10° and 80°, particularly preferably 45°. The ratio B / H is preferably between 0.2 and 5, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably between 0.1 and 0.5.

[0068] As shown in FIG. 6F, the recess 50 Lovett and a fillet. In other words, the transition from the first recess surface 53 to the second recess surface 54 can be formed by a curved recess surface 56, the cross section of which preferably corresponds to a circular cross section. The fillet can have a radius R, and the ratio R / D is preferably 0.05 to 2. The ratio B / H is preferably 0.2 to 10, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0069] Furthermore, as shown in FIG. 6G, the recess 50 can be formed by a fillet, i.e., by a groove with a round cross section, in the region of the outer edge that is no longer present due to a groove between the contact surface 41 and the outer surface 43. In this case, the first and second outer edges 51, 52 are connected to one another via a curved recess surface 53, preferably having a cross section corresponding to the circular cross section. The fillet can have a radius R, and the ratio R / D is preferably 0.05 to 2. The ratio B / H is preferably 0.2 to 10, particularly preferably 1. Furthermore, the ratio H / D is preferably greater than 0 and less than 0.8, particularly preferably 0.1 to 0.5.

[0070] The side surfaces of the recess can form so-called sacrificial areas onto which arcs occurring between the contact surfaces of the fixed and movable contacts can "jump." This can be facilitated in particular by at least one contact surface projecting laterally beyond, or at least coinciding with, the counter contact surface with the recess. In this way, arcs can be kept away from the contact surfaces, thereby reducing the risk of arc-induced damage to the contact surfaces, in particular the contact areas, and the associated deterioration of the contact resistance.

[0071] The features and embodiments described in connection with 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 connection with the drawings can alternatively or additionally have further features according to the description in general part.

[0072] The present invention is not limited by the description based on the examples, but rather includes all novel features and all combinations of features, including 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]

[0073] 1 Contact 2 Fixed contacts 3. Insulators 4 Movable contacts 5 Magnet Armature 6 magnetic core 7 axes 8 coils 9 York 10 springs 11 Switching Chamber 12 Switching chamber wall 13 Bottom of switching chamber 14 Airtight Zone 15 Interior Space 16 Permanent magnets 20,40 Contact side 21,41 Contact surface 22,42 contact area 23,43 Exterior 34 Contact spring 50 recess 51,52 outer edge 53,54 Concave surface 55 Common-law marriage 56 Concave surface 90 horizontal 91 vertical direction 92 Longitudinal 93 Transverse 100 Switching Device B distance D Thickness H distance T2,T4 width α1, α2, α3, α4 angles

Claims

1. A switching device (100) comprising at least two contacts (1) in a switching chamber (11), The at least two contacts include a fixed contact (2) and a movable contact (4); Each of said contacts has a contact surface (21, 41) on a contact side (20, 40) with at least one contact area (22, 42), At least one of the contacts has at least one recess (50) that defines a first outer edge (51) adjacent the contact surface and a second outer edge (52) adjacent the outer surface; The recess comprises a rabbet, an internal chamfer, a fillet, or a combination thereof; and / or the contact surface has a main extension plane, the direction parallel to the main extension plane is the lateral direction (90) and the direction perpendicular to the main extension plane is the vertical direction (91), the distance between the first outer edge and the second outer edge is denoted H in the vertical direction and B in the lateral direction, B / H being ≧0.2 and ≦5, the total thickness of the contact in the vertical direction is denoted D, H / D being ≧0 and ≦0.8, the recess has at least one curved recess surface with a cross section corresponding to a circular cross section with a radius R, R / D being ≧0.05 and ≦2, A switching device (100).

2. 2. The switching device (100) of claim 1, wherein the fixed contact has a contact surface that projects beyond the contact surface of the movable contact in at least one lateral direction.

3. 3. The switching device (100) according to claim 1 or 2, wherein at least one of the movable contacts (4) has at least one recess (50) on the contact side (40).

4. The switching device (100) according to any one of claims 1 to 3, wherein at least one of the fixed contacts (2) has at least one recess (50) on the contact side (20).

5. The switching device (100) according to any one of claims 1 to 4, wherein each of the contacts (1) has at least one recess (50).

6. A switching device (100) according to any one of claims 1 to 5, wherein at least one recess (50) is formed by a groove or a slope, the groove or slope being formed by the contact surface and the outer surface (23, 43) and extending between the contact surface and the outer surface along an imaginary edge that is no longer present due to the groove or slope.

7. The switching device (100) of any one of claims 1 to 6, wherein the first outer edge and the second outer edge are connected to each other by one or more recessed surfaces (53, 54, 56).

8. The switching device (100) according to any one of claims 1 to 7, wherein the recess has at least one recess surface that forms an angle of 10° to 80° with the contact surface.

9. The switching device (100) according to any one of claims 1 to 8, wherein recesses are formed in the contact sides in different lateral directions.

Images