Emergency electrical switching device with a connecting element for producing an electrically conductive connection

Abstract

The invention relates to an electrical emergency switching device with a connecting element for establishing an electrically conductive connection between at least two contact arrangements. It comprises a pyrotechnic release for moving the connecting element from a standby position, in which the contact arrangements are electrically isolated from one another, to an operating position, in which the contact arrangements are electrically connected to one another, with the connecting element contacting a contact surface of each contact arrangement. The release, the connecting element, and the contact surfaces are arranged in a housing. The contact arrangements are each formed on a busbar that extends through a tunnel formed in the housing, the tunnels being arranged parallel to one another.In a special embodiment of the switching device, it can be mounted on existing busbars.

Description

[0001] The invention relates to an electrical emergency switching device according to the preambles of claims 1 and 11.

[0002] The increasing use of large-capacity electric batteries and fuel cells, such as those used as intermediate storage in stationary photovoltaic systems or in batteries for electric vehicles, is accompanied by a correspondingly greater risk potential in the event of accidental short circuits. For example, a fire caused by an accident involving an electric vehicle can hamper firefighting efforts because firefighters could be injured by electric shocks. Accidental damage to the vehicle's electrical system itself can also result in short-circuit currents of several thousand amperes. The resulting heat can, in extreme cases, even cause the battery system or fuel cell to explode.Safe shutdown devices have therefore already been proposed, designed to discharge the residual energy stored in the fuel cell in a very short period of time. These devices incorporate a short-circuit device that can be activated by the action of an explosive charge.

[0003] The object of the present invention was to provide an electrical emergency switching device with which several main current conductors can be contacted, short reaction times are achieved and the use of materials required to create particularly well-protected electrical systems is reduced.

[0004] This object is achieved by a device and a method according to the claims.

[0005] The electrical emergency switching device according to the invention, comprising a connecting element for establishing an electrically conductive connection between at least two contacting arrangements, comprises an electrically controllable, pyrotechnic trigger for moving the connecting element from a standby position to an operational position. In the standby position, the contacting arrangements are electrically insulated from one another, and in the operational position, the contacting arrangements are electrically conductively connected to one another by the connecting element, with one contact surface of each of the contacting arrangements being touched by the connecting element. The trigger, the connecting element, and the contact surfaces are arranged in a housing.The contact arrangements are each formed on a busbar, each of which extends through a tunnel formed in the housing. The tunnels are arranged parallel to one another. Such a switching device has the advantage that it can be used to switch several phases to be switched simultaneously in an electrical system, thus achieving a particularly short response time.

[0006] In an advantageous development of the switching device, at least three contact arrangements are formed, each encompassing a busbar. This is advantageous because, for example, in the case of an electric vehicle motor, the three phases of the motor can be short-circuited, thus discharging the residual energy of the corresponding coils.

[0007] In an advantageous embodiment of the switching device, it is provided that the housing comprises an upper housing part and a lower housing part, wherein the tunnels are formed in the lower housing part.

[0008] Furthermore, it is provided that the pyrotechnic trigger is formed in the upper part of the housing and comprises at least one propellant charge.

[0009] Preferably, the pyrotechnic trigger also includes a connector for electrically connecting the propellant charge. Using a pyrotechnic propellant charge to move the connecting element allows for particularly short reaction times.

[0010] In a preferred embodiment of the switching device, a piston is formed in the upper housing section, with the connecting element being attached to the piston for movement from the standby position to the operating position. The piston absorbs the pressure of the combustion gases when the propellant charge is ignited and, thanks to its precise, linear guidance, ensures the most simultaneous contact possible between the connecting element and the busbars.

[0011] It is also advantageous if the switching device is designed such that the longitudinal axes of the tunnels span a common plane, wherein the direction of movement of the connecting element is oriented perpendicularly relative to the plane of the longitudinal axes.

[0012] In a further development of the switching device, the connecting element comprises at least one downwardly projecting leg extending transversely to the busbars, and the contact arrangements are each formed by a groove aligned with the leg. The advantage here is that when the leg moves into the groove—when the connecting element is moved from the standby position to the use position—sufficiently large contact surfaces can form between the side surfaces of the leg and the walls of the groove.

[0013] The design of the switching device, in which a width of the leg and a width of the grooves of the contacting arrangements are each dimensioned to form a press fit, has the advantage of a higher contact pressure when making the contact in the operating position.

[0014] It is also advantageous if the ends of the busbars that protrude outwards from the housing are each designed as a contact lug.

[0015] In a preferred embodiment of the switching device, the housing is designed to be dust and liquid tight.

[0016] The object of the invention is also achieved independently by an electrical emergency switching device with a connecting element for establishing an electrically conductive connection between at least two contacting arrangements and with an electrically controllable, pyrotechnic trigger for moving the connecting element from a standby position to an operational position, wherein in the standby position the contacting arrangements are electrically insulated from one another, and wherein in the operational position the contacting arrangements are electrically conductively connected to one another by the connecting element.The trigger and the connecting element are arranged in a housing, wherein at least two tunnels extending through the housing with a rectilinear longitudinal axis are formed in the housing, wherein the longitudinal axes of the tunnels are aligned perpendicular to a direction of movement of the connecting element, and wherein the tunnels are arranged according to the deployment position of the connecting element.

[0017] An advantageous design of the switching device provides for the formation of three or more tunnels. This has the advantage that in an electrical system with three or more phases to be switched, these can be switched simultaneously, thus achieving a particularly short response time during short-circuiting. This also minimizes the amount of material required to manufacture the switching device.

[0018] Another advantage is that the tunnels are each designed with a rectangular cross-section, as this allows a combination with standardized busbar cross-sections.

[0019] According to a further development of the switching device, the cross section of the tunnels is designed to correspond to a cross section of a busbar.

[0020] It is also advantageous if the longitudinal axes of the tunnels are arranged parallel to each other.

[0021] Also advantageous is a further development of the switching device in which the housing comprises an upper housing part and a lower housing part and the tunnels extending through the housing are formed lying between an underside of the upper housing part and an upper side of the lower housing part.

[0022] It is particularly advantageous if the tunnels are formed by an upwardly open, rectangular groove in the lower housing section and by the underside of the upper housing section. This has the advantage that a housing designed in this way also allows existing high-power electrical systems to be retrofitted with an emergency switching device.

[0023] According to a preferred embodiment of the switching device, the pyrotechnic trigger is formed in the upper housing part and comprises at least one propellant charge. Using pyrotechnic propellant charges, particularly short reaction times can advantageously be achieved.

[0024] It is also advantageous to have a design in which the pyrotechnic trigger includes a plug for electrical contact with the propellant charge.

[0025] In a particularly preferred embodiment of the switching device, a piston is formed in the upper housing section, with the connecting element being attached to the piston for movement from the standby position to the operating position. This has the advantage that, in the event of ignition of the propellant charge, the piston absorbs the pressure of the combustion gases and, at the same time, ensures precise, linear guidance of the connecting element along the inner walls of the housing.

[0026] Also advantageous is the design of the switching device in which the longitudinal axes of the tunnels span a common plane and a direction of movement of the connecting element is oriented perpendicularly relative to the plane of the longitudinal axes.

[0027] Preferably, the connecting element comprises downwardly projecting teeth arranged in a comb-like row, with the row of teeth extending transversely to the longitudinal axes of the tunnels. This has the advantage that, when the connecting element is moved into the insertion position, any oxide layers or insulation present on the contact surfaces of the contacting arrangements are sheared off, thus exposing bare, metallic contact surfaces.

[0028] For a better understanding of the invention, it is explained in more detail using the following figures.

[0029] They show in a highly simplified, schematic representation: Fig. 1 shows an emergency switching device in the assembled or mounted state in perspective; Fig. 2 shows the most important functional elements of the switching device according to Fig. 1 shown in perspective; Fig. 3 the switching device according to Fig. 1in exploded view; Fig. 4 shows a further embodiment of the emergency switching device in perspective; Fig. 5 shows a cross section of the switching device according to Fig. 4 , perpendicular to the longitudinal axes of the tunnels and shown in perspective.

[0030] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0031] Based on the Fig. 1 to 3A first embodiment of an electrical emergency switching device 1 is described. Fig. 1 shows the switching device 1 in the assembled or mounted state in perspective. According to this exemplary embodiment, three busbars 2, so-called busbars, are fastened in a housing 3. The housing 3 is designed such that one end of each of the busbars 2 protrudes from the housing 3 on both sides. This means that the busbars 2 extend through the housing 3. The two ends of the busbars 2 are also designed as contact lugs 4, 5 (in Fig. 1 (indicated by a hole each). Using the two contact lugs 4, 5, the three busbars 2 can be integrated into three separate phases of a power circuit. This means that, during operation, electrical current flows through the busbars 2.

[0032] The housing 3 is furthermore designed such that the three busbars 2 are arranged at a defined distance relative to one another and run parallel to one another. For this purpose, the housing 3 has three tunnels 6 extending through the housing. The housing 3 advantageously comprises an upper housing part 7 and a lower housing part 8. According to this exemplary embodiment of the switching device 1, the three tunnels 6 for the busbars 2 run through the lower housing part 8.

[0033] The Fig. 2 shows selected elements of the switching device 1 according to Fig. 1shown in perspective. For the sake of clarity, only the most functionally important elements are shown here. Above the three adjacently arranged busbars 2 there is a connecting element 9, the position shown corresponding to a standby position of the connecting element 9. This means that the connecting element 9 is located at a sufficiently large distance from the busbars 2 so that they are electrically insulated from the connecting element 9. Furthermore, a propellant charge 10 is shown above this connecting element 9. This propellant charge 10 is part of an electrically controllable, pyrotechnic trigger for moving the connecting element 9 from the standby position into an operational position. The busbars 2 are each formed with a contact arrangement 11 corresponding to the external shape or design of the connecting element 9.In this embodiment, the connecting element 9 has two downward-facing legs. The contact arrangements 11 of the busbars 2 are accordingly each designed with two upwardly open grooves. The two legs of the connecting element 9 extend transversely across the three busbars 2.

[0034] If the connecting element 9 is moved downwards in the direction of movement 12 into its deployment position (indicated by dashed lines) under the action of the ignited propellant charge 10, the contacting arrangements 11 of all three busbars 2 are electrically connected to one another via the connecting element 9. In doing so, contact surfaces of each of the contacting arrangements 11 are touched by the connecting element 9, so that the three busbars 2 are short-circuited to one another. The legs of the connecting element 9 advantageously have a width dimensioned such that, when the connecting element 9 is moved into the deployment position, any oxide layers or insulation that may be present on the contact surfaces of the contacting arrangements 11 (the two side walls of the grooves) are sheared off. For this purpose, the width of the legs and a width of the grooves are each dimensioned to form a press fit.By shearing off oxide layers or insulation in this way, bare metallic surfaces are exposed as effective contact surfaces, while at the same time an electrically conductive connection is established.

[0035] The Fig. 3 shows the switching device 1 according to Fig. 1in exploded view. As can be seen more clearly from the illustration, the lower housing part 8 is formed with three tunnels 6 which run parallel to one another. The tunnels 6 for receiving the busbars 2 are arranged in such a way that the longitudinal axes 13 of the tunnels 6 span a common plane, with the direction of movement 12 of the connecting element 9 being aligned perpendicular to the plane of the longitudinal axes 13. Above the connecting element 9, a piston 14 is shown, to which - in the assembled state of the switching device 1 - the connecting element 9 is fastened. When the propellant charge 10 is ignited, the piston 14 absorbs the resulting pressure of the combustion gases and thereby displaces the connecting element 9 downwards into its operational position. Above the upper end of the upper housing part 7, there is also a plug 15 for contacting the electrically controllable pyrotechnic trigger orfor igniting the propellant charge 10.

[0036] The described emergency switching device 1 allows multiple busbars or multiple busbars 2 to be short-circuited simultaneously. The switching device 1 can therefore be used, for example, to short-circuit the three phases of an electric vehicle motor with a response time of a few milliseconds. However, variants of the switching device 1 are also possible in which only two or more than three busbars 2 are present instead of three.

[0037] In the Fig. 4 and 5 a further and possibly independent embodiment of the emergency switching device 1 is shown, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 1 to 3To avoid unnecessary repetition, reference is made to the detailed description of the preceding figures.

[0038] The Fig. 4 shows the switching device 1 in perspective. The switching device 1 can be attached to three parallel busbars 16. In this version of the switching device 1, the three busbars 16 themselves are not part of the emergency switching device 1. To clarify this, Fig. 4The busbars 16 are shown only by dashed lines. The switching device 1 is thus suitable for retrofitting in existing high-power electrical systems. The housing 3 of this switching device 1 has a housing upper part 17 and a housing lower part 18, wherein the tunnels 6 extending through the housing 3 are formed lying between a bottom side 19 of the housing upper part 17 and a top side 20 of the housing lower part 18. In the Fig. 4 In the illustrated embodiment, the lower housing part has an upwardly open, rectangular groove 21 for each of the three tunnels 6. The tunnels 6 are delimited at the top by the underside 19 of the upper housing part 17.

[0039] The Fig. 5 shows a cross section of the switching device 1 according to Fig. 4 , cut vertically relative to the longitudinal axes 13 of the tunnels 6 and shown in perspective. Fig. 5 the switching device 1 is shown in a state connected to the busbar 16.

[0040] The switching device 1 according to this exemplary embodiment can be fastened to the busbars 16 in such a way that the lower housing part 18 is first guided from below onto the busbars 16 until each of them rests in one of the grooves 21 of the lower housing part 18. The upper housing part 17 can then be placed onto this arrangement and connected to the lower housing part 18. A screw connection between the upper housing part 17 and the lower housing part 18 can be used, for example, to fasten the switching device 1 to the busbars 16.

[0041] In the, in Fig. 5In the illustration shown, the piston 14 with the connecting element 9 attached to it is in the standby position. This means that the connecting element 9 is arranged at a distance from the busbars 16, and the contact arrangements 11 of the busbars 16 are therefore electrically insulated from one another. In this exemplary embodiment, the upper side regions of the busbars 16 facing the connecting element 9 function as contact arrangements 11 of the busbars 16. The connecting element 9 is accordingly designed with comb-like, downwardly projecting teeth 22. This comb-like sequence of teeth 22 of the connecting element 9 extends transversely to the busbars 16 arranged parallel to one another.

[0042] When the switching device 1 is activated, the connecting element 9 is moved from the standby position to its deployment position as a result of the ignition of the propellant charge 10 of the pyrotechnic trigger. During this movement, the teeth 22 of the connecting element 9 are pushed into the spaces between the busbars 16. This means that the contact arrangements 11 of the busbars 16 come to rest in the gaps between the teeth 22 of the connecting element 9. The teeth 22 and their spacing relative to one another are dimensioned and the teeth 22 are arranged such that any oxide layers or insulation present on the contact surfaces of the contact arrangements 11 are sheared off during this movement of the connecting element 9 into the deployment position.For this purpose, the width of a busbar 16 and the clearance between adjacent teeth 22 are each dimensioned to form a press fit. By shearing off oxide layers or insulation in this way, bare metallic surfaces are exposed as effective contact surfaces, by means of which an electrically conductive connection can be established simultaneously. This ensures that, in the deployed position of the connecting element 9, the contact arrangements 11 of the busbars 16 are electrically conductively connected and short-circuited by the connecting element 9.

[0043] The embodiments show possible embodiments, whereby it should be noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but rather various combinations of the individual embodiments with each other are also possible and this possibility of variation lies within the skill of the person skilled in the art in this technical field due to the teaching of technical action by means of the objective invention.

[0044] The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various embodiments shown and described may represent independent inventive solutions. The problem underlying these independent inventive solutions can be derived from the description.

[0045] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0046] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size. Reference symbol list

[0047] 1Emergency switching device 2Busbar 3Housing 4Contact lug 5Contact lug 6Tunnel 7Housing upper part 8Housing lower part 9Connecting element 10Propellant charge 11Contacting arrangement 12Direction of movement 13Longitudinal axis 14Piston 15Plug 16Busbar 17Housing upper part 18Housing lower part 19Underside 20Top side 21Groove 22Tooth

Claims

1. Electrical emergency switching device (1) with a connecting element (9) for establishing an electrically conductive connection between at least two contacting arrangements (11) and with an electrically controllable, pyrotechnic trigger for moving the connecting element (9) from a standby position to an operational position, wherein in the standby position the contacting arrangements (11) are electrically insulated from one another, and wherein in the operational position the contacting arrangements (11) are electrically conductively connected to one another by the connecting element (9) such that one contact surface of each of the contacting arrangements (11) is touched by the connecting element (9), and wherein the trigger, the connecting element (9) and the contact surfaces are arranged in a housing (3), characterized in thatthe contacting arrangements (11) each comprise a busbar (2), wherein the busbars (2) each extend through a tunnel (6) formed in the housing (3), and wherein the tunnels (6) are arranged to run parallel to one another.

2. Switching device (1) according to claim 1, characterized in that at least three contacting arrangements (11) each comprising a busbar (2) are formed.

3. Switching device (1) according to claim 1 or 2, characterized in that the housing (3) comprises an upper housing part (7) and a lower housing part (8), wherein the tunnels (6) are formed in the lower housing part (8).

4. Switching device (1) according to one of the preceding claims, characterized in that the pyrotechnic trigger is formed in the upper housing part (7) and comprises at least one propellant charge (10).

5. Switching device (1) according to one of the preceding claims, characterized in thatthe pyrotechnic trigger comprises a plug (15) for electrically contacting the propellant charge (10).

6. Switching device (1) according to one of the preceding claims, characterized in that a piston (14) is formed in the upper housing part (7), wherein the connecting element (9) is fastened to the piston (14) for movement from the standby position to the use position.

7. Switching device (1) according to one of the preceding claims, characterized in that Longitudinal axes (13) of the tunnels (6) span a common plane, wherein a direction of movement (12) of the connecting element (9) is oriented perpendicularly relative to the plane of the longitudinal axes (13).

8. Switching device (1) according to one of the preceding claims, characterized in thatthe connecting element (9) comprises at least one downwardly projecting leg extending transversely to the busbars (2), and the contacting arrangements (11) each comprise a groove aligned with the leg.

9. Switching device (1) according to one of the preceding claims, characterized in that a width of the leg and a width of the grooves of the contacting arrangements (11) are each dimensioned to form a press fit.

10. Switching device (1) according to one of the preceding claims, characterized in that ends of the busbars (2) projecting outwards from the housing (3) are each designed as a contact lug (4, 5).

11. Electrical emergency switching device (1) with a connecting element (9) for establishing an electrically conductive connection between at least two contacting arrangements (11) and with an electrically controllable, pyrotechnic trigger for moving the connecting element (9) from a standby position to an operational position, wherein in the standby position the contacting arrangements (11) are electrically insulated from one another, and wherein in the operational position the contacting arrangements (11) are electrically conductively connected to one another by the connecting element (9), wherein the trigger and the connecting element (9) are arranged in a housing (3), characterized in thatin the housing (3) at least two tunnels (6) extending through the housing (3) are formed with a rectilinear longitudinal axis (13), wherein the longitudinal axes (13) of the tunnels (6) are aligned perpendicular to a direction of movement (12) of the connecting element (9), and wherein the tunnels (6) are arranged according to the insertion position of the connecting element (9).

12. Switching device (1) according to claim 11, characterized in that three tunnels (6) are formed.

13. Switching device (1) according to one of claims 11 or 12, characterized in that the tunnels (6) are each formed with a rectangular cross-section 14. Switching device (1) according to one of claims 11 to 13, characterized in that the cross-section of the tunnels (6) is designed to correspond to a cross-section of a busbar.

15. Switching device (1) according to one of claims 11 to 14, characterized in thatthe longitudinal axes (13) of the tunnels (6) are arranged parallel to one another.

16. Switching device (1) according to one of claims 11 to 15, characterized in that the housing (3) comprises an upper housing part (17) and a lower housing part (18), and the tunnels (6) extending through the housing (3) are formed lying between an underside (19) of the upper housing part (17) and an upper side (20) of the lower housing part (18).

17. Switching device (1) according to one of claims 11 to 16, characterized in that the tunnels (6) are each formed by an upwardly open, rectangular groove (21) of the lower housing part (18) and by the underside (19) of the upper housing part (17).

18. Switching device (1) according to one of claims 11 to 16, characterized in that the pyrotechnic trigger is formed in the upper housing part (7) and comprises at least one propellant charge (10).

19. Switching device (1) according to one of claims 11 to 18, characterized in that the pyrotechnic trigger comprises a plug (15) for electrically contacting the propellant charge (10).

20. Switching device (1) according to one of claims 11 to 19, characterized in that a piston (14) is formed in the upper housing part (7), wherein the connecting element (9) is fastened to the piston (14) for movement from the standby position to the use position.

21. Switching device (1) according to one of claims 11 to 20, characterized in that Longitudinal axes (13) of the tunnels (6) span a common plane, wherein a direction of movement (12) of the connecting element (9) is oriented perpendicularly relative to the plane of the longitudinal axes (13).

22. Switching device (1) according to one of claims 11 to 21, characterized in thatthe connecting element (9) comprises teeth (22) arranged in a row in a comb-like manner and projecting downwards, the row of teeth (22) extending transversely to the longitudinal axes (13) of the tunnels (6).

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