WO2024103096A1

WO2024103096A1 - Electric emergency switch device

Info

Publication number: WO2024103096A1
Application number: PCT/AT2023/060395
Authority: WO
Inventors: Erwin Lichtenberg; Benedikt RIAUTSCHNIG
Original assignee: Miba Emobility Gmbh
Priority date: 2022-11-15
Filing date: 2023-11-15
Publication date: 2024-05-23

Abstract

The invention relates to an electric emergency switch device comprising a housing (1, 2), at least one electrically controllable pyrotechnic trigger (8, 9, 10), and at least two contact elements (3, 6) each having at least one contacting surface (6) located inside the housing and at least one contact lug (3) guided to the outside of the housing. The contacting surfaces (6) of all contact elements are at a distance from one another. An electrically conductive connection element (7) has a standby position and a self-locking insertion position, wherein the connection element (7) in the standby position does not touch any of the contacting surfaces (6) and in the insertion position contacts the contacting surfaces (6) of both contact elements, thus establishing an electrically conductive connection between the contact elements (3, 6). The connection element (7) is moved by the pyrotechnic trigger (8, 9, 10) from the standby position into the insertion position. A retaining part (11) holds the connection element (7) in the standby position and at a distance from the contact elements (3, 6) and isolated therefrom.

Description

ELECTRICAL NQFALL SWITCHING DEVICE

The invention relates to an electrical emergency switching device according to the preamble of patent claim 1.

EP2030212A1 discloses a method and a device for extinguishing an arc fault in a medium and high voltage switchgear. In this case, at least one short-circuit switching element is connected between the phases of a three-phase distribution. To do this, the short-circuit switching element is fired by means of an explosive charge acting directly on the short-circuit switching element onto a conical contact structure connected to the three-phase conductors and designed to complement the short-circuit switching element. Due to the complementary contours of the short-circuit switching element and the three-phase conductors, a self-locking retention in the short-circuit position is achieved without the need for a holding force.

WO9619816A1 discloses an electrical switching device for the rapid, simultaneous electrical closing of at least three conductors intended for high current and high voltage. The switching device consists of a housing in which an electrically insulating flame tube is arranged, with insulators connected to the housing, via which the conductors are connected to contacts arranged in the flame tube. At one end of the tube, a projectile made of conductive material is held in a ready position, and at the other end of the tube, a damping block is arranged. The pressure force of an explosive charge pushes the projectile into an operational position in which it is clamped between the contacts and causes an electrical short circuit between the contacts.

Pyrotechnically activated switching devices are also known for quickly separating electrical connections or interrupting circuits. In the field of electromobility, electrical safety can be quickly restored in the event of an accident. In industrial applications, a short circuit can be quickly created to bridge failed power components or to support the triggering of other safety components.

Such an emergency switching device is already known from DE 102017106117 B3. A connecting element is covered by insulation caps in order to Standby position to keep the connecting element insulated from the contact arrangements. When the connecting element is pyrotechnically moved from the standby position to the use position, the insulating layer is destroyed and the connecting element comes into electrically conductive contact with both associated contacts of the contact arrangements, thus closing the circuit.

DE 19712387 A1 also discloses an emergency switching device with a first and a second contact unit and with a connecting element that can be moved between a standby position and a self-locking operating position by a pyrotechnic charge. A retaining part inside the housing that is clamped between the contact surfaces in the standby position projects with at least a portion of its cross section into the path of the connecting element during its movement from the standby position to the operating position. In this way, the connecting element is kept spaced apart and insulated from the contact arrangements and can only be pushed away during a pyrotechnically induced movement of the connecting element.

US 4417519 A also discloses a switching device with two contact units and a connecting element with a standby position and a self-locking operating position. An electrically insulating retaining part in the interior of the housing projects with at least a portion of its cross section into the path of the connecting element in order to keep it spaced apart from the contact arrangements and insulated in the standby position. When pyrotechnics are triggered, the retaining part is pushed away from the moving connecting element.

EP 1052665 A2 also shows a similar switching device with an insulating layer designed as a retaining part, whereby this insulating membrane is destroyed in the course of a pyrotechnically induced movement of a connecting element. In the standby state, the connecting element is held by the retaining part and is electrically insulated from the contacting arrangements.

Furthermore, DE 9419141 Ul also discloses a corresponding switching device in which an insulating layer arranged between two contacting arrangements keeps a cylindrically shaped connecting element, which in its standby position touches the contacting surface of one contacting arrangement, insulated from the contacting surface of the other contacting arrangement. A pyrotechnically induced movement of the Fastening element leads to destruction of the insulating layer due to the movement of the fastener into the insertion position.

The two other documents DE 102019101307 B3 and US 2003231443 A1 also show similar switching devices, with DE 102019101307 B3 disclosing a connecting element that is embedded in an insulating layer. The retaining part of US 2003231443 A1, which insulates the connecting element in its standby position and keeps it at a distance from the contacting arrangements, is designed as an insulating pin clamped between the contacting surfaces of the two contacting arrangements, which is destroyed in the event of a pyrotechnically induced movement.

The object of the present invention was to improve the previously known solutions and to create a device with which an electrical circuit can be short-circuited as quickly as possible in an emergency in order to destroy available residual energy as quickly as possible or to earth a consumer or a power source.

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

The device according to the invention is based on a switching device comprising a dust- and liquid-tight housing made of electrically insulating material and at least one electrically controllable pyrotechnic trigger. By means of this trigger, in an emergency or operational situation, for example for short-circuiting PV systems or fuel cells, for rapid energy discharge in a short period of time, for example in emergencies in electric vehicles, or also for rapid earthing, a circuit between two contact arrangements can be closed by means of a connecting element that can be moved from a standby position to an operational position.

Furthermore, the device comprises at least one pair of associated contact arrangements, each with at least one contact lug arranged on the outside of the housing, and at least one contact surface located inside the housing for each contact arrangement, wherein at least two contact surfaces of each pair of contact arrangements are spaced apart from one another at least in a standby state of the switching device, an electrically conductive connecting element inside the housing, which has a standby position and a self-locking use position, which only in the use position contacts the contact surfaces of both contacting arrangements of the associated pair, whereby an electrically conductive connection is thus established within the pair of contacting arrangements.

At least one retaining part inside the housing projects with at least a portion of its cross section into the path of the connecting element as it moves from the standby position to the deployment position, thus keeping the connecting element insulated from the contacting arrangements. For this purpose, the retaining part is either positioned in the housing so as to be electrically insulated from the contacting surfaces, or alternatively or additionally is itself made of insulating material for optimal electrical insulation of the contacting surfaces. Furthermore, according to the invention, the retaining part is designed in such a way that it is only destroyed, deformed or pushed away during a pyrotechnically induced movement of the connecting element from the standby position to the deployment position. This can happen, for example, by breaking or breaking off holding arms for the connecting part. Alternatively, the retaining part could also be deformed only to the extent that the connection can move steeply relative to it and reach the deployment position. Pushing it away into a housing cavity or out of the housing, possibly destroying the housing, is also conceivable.

The term "a pair of associated contact arrangements" is to be understood as meaning that these are contact arrangements whose electrically conductive connection (short-)circuits an electrical circuit. The separate retaining part, which keeps the conductive sections of the contact arrangements separate from one another and thus electrically insulated, minimises the risk of the connecting element being accidentally moved into the operating position, particularly in applications subject to high mechanical stress. The occurrence of leakage currents is also minimised by the additional insulating function.

To achieve the stated object, the switching device according to the invention is characterized in that the retaining part is designed as a pin-shaped element with a widened end and is fixed with the pin-shaped section parallel to the contact surfaces in the area between the contact elements in the housing lower part and is separated at least from the contact arrangements by a corresponding distance and/or by Intermediate layers made of an insulating material are electrically insulated. This ensures that the retaining part is anchored securely and electrically insulated under all circumstances.

Preferably, the retaining part is electrically insulated from the connecting element by an appropriate distance and/or by intermediate layers made of an insulating material. This ensures that no thermal or mechanical stress can lead to an unwanted closing of the circuit.

A preferred embodiment of the switching device according to the invention provides that the retaining part has a widening that projects perpendicularly to its longitudinal extension and engages the connecting element, the widening preferably being formed by four orthogonal tongues that project perpendicularly to the longitudinal extension of the retaining part. This allows a secure holding effect on the connecting element held in a precisely defined position with a material-saving design of the retaining part. At the same time, however, the retaining part can be overcome with a relatively low, precisely definable amount of force in the event of a trigger.

A preferred embodiment is one in which slots are made in the connecting element to encompass the contact surfaces of the contact elements, whereby the tongues of the retaining part then engage in those peripheral sections of the connecting element that are free of slots and that are also located outside the area of the contact surfaces. This design ensures the optimal spatial and/or electrical separation of the contact elements and the connecting element, while at the same time providing a precisely definable retaining effect and a precisely definable amount of force for the destruction or deformation of the retaining part when triggered.

In another embodiment of an emergency switching device, comprising at least one pair of associated contacting arrangements, each consisting of at least one contacting surface located inside the housing and at least one contact lug guided to the outside of the housing, wherein the contacting surfaces of each pair of contacting arrangements are spaced apart from one another inside the housing, wherein a connecting element in the standby position touches a maximum of one of the contacting surfaces of the contact elements, it is provided according to the invention that by means of a A retaining part that is electrically insulated from the contact surfaces or made of insulating material keeps the connecting element at a distance from the other contact surfaces of the associated pair and insulates it from them. This makes it possible to achieve the same technical effects and advantages as explained for the first embodiment.

Yet another embodiment of an emergency switching device according to the invention comprises at least a first contact arrangement, consisting of at least one contact surface located inside the housing and at least one contact lug guided to the outside of the housing, furthermore at least a second contact arrangement consisting of at least one contact lug arranged on the outside of the housing, a line section electrically connected to it and a connecting element electrically connected to it, and is characterized according to the invention in that the connecting element is kept at a distance from the contact surface of the first contact arrangement in the standby position and is insulated from it by the retaining part which is electrically insulated from the contact surfaces or made of insulating material. This makes it possible to achieve the same technical effects and advantages as were explained for the first embodiment.

In this last embodiment, a variant is preferred in which, according to an optional feature of the invention, the connecting element in the standby position is embedded in an insulating layer at least with its section facing the contacting surfaces or the contacting surfaces are covered by an insulating layer, and wherein the connecting element has pierced the insulating layer in the use position.

A structurally simple and functionally reliable embodiment is preferred in which the connecting element can be moved along a straight path. The connecting element can preferably be moved along a longitudinal axis of the housing. A further optional variant is characterized in that the connecting element is guided relative to the housing by means of an anti-twist device.

According to another advantageous development of the invention, it is provided that the connecting element is mounted on an axis in relation to the contact elements in the housing so as to be rotatable or pivotable along a curved path and that the at least one further contact element in the standby position is in at least one predeterminable Angular distance of the contact surface of the first contact element is arranged downstream in the direction of rotation.

A further preferred embodiment of the invention provides that the retaining part which is electrically insulated from the contacting surfaces or made of insulating material rests against the connecting element in the standby position and thus keeps the connecting element in the standby position and the contacting arrangements insulated.

For optimal integration of the switching device according to the invention into the control of the arrangement to be secured, it is advantageous if the pyrotechnic trigger comprises an electrically ignitable propellant charge and a piston that can be displaced in the housing by the action of the propellant charge, which piston acts directly or indirectly on the connecting element. An embodiment of a connecting element that is designed as a piston at one end is also conceivable.

Preferably, the propellant charge, including the connection of the control lines, is cast in a different material than that of the housing. This avoids a capillary effect due to different expansion coefficients.

The piston can advantageously also be guided relative to the housing by means of an anti-twisting device.

According to the invention, the connecting element is preferably designed in such a way as to cause shearing off of any surface coating or oxide layer formed on the contact surfaces. In this way, the insulating effect can be optimally maintained in the standby state of the switching device, while the best possible electrical contact is ensured in an emergency.

This effect is further enhanced if slots are formed in the connecting element, the inner sides of which contact the contact surfaces of the contact elements on opposite sides in the inserted position.

Preferably, the connecting element is designed as a cylinder or sleeve that is open towards the contact elements. According to an advantageous embodiment of the invention, the clear width of the slots is smaller than the thickness of the contact elements in the area of the contact surfaces, possibly including surface coatings and/or oxide layers. This results in the connecting element being formed (cold molded) onto the contact elements, which leads to a permanent and irreversible holding effect.

A further embodiment of the switching device according to the invention is characterized in that the retaining part is designed as a pin-shaped element with a widened end and is arranged parallel to the contact surfaces in the area between the contact elements, and rests with the widened end on the connecting element in its ready position.

A further embodiment according to the invention is characterized in that at least one contact arrangement of each pair is connected to a resistor and preferably additionally to a heat accumulator. This ensures that in an emergency and after the switching device has been triggered, the electrical energy released in a short time is safely converted into heat.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

They show in a highly simplified, schematic representation:

Fig. 1 is a perspective view of an emergency switching device according to the invention;

Fig. 2 is an exploded view of the switching device of Fig. 1;

Fig. 3 is a longitudinal section through the switching device of Fig. 1;

Fig. 4 is a perspective side view of the components propellant charge, piston, connecting element, retaining part and contact elements of the switching device of Fig. 1;

Fig. 5 is an oblique view from above of the housing seal and the retaining part of the switching device of Fig. 1; Fig. 6 is a perspective, partially schematic side view of the contact arrangements of a further embodiment of an emergency switching device according to the invention.

The position information chosen in the description, such as top, bottom, side, etc., refers to the figure directly described and shown, and if the position changes, these position information must be transferred to the new position. All information on value ranges in the actual description is to be understood as including any range and all subranges thereof, e.g. the information 1 to 10 is to be understood as including all subranges, starting from the lower limit 1 and the upper limit 10, i.e. all subranges start 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.

The embodiments show a possible embodiment variant, whereby the invention is of course not restricted to this specifically illustrated embodiment variant.

The electrical emergency switching device according to the invention in Fig. 1 has a dust- and liquid-tight housing, consisting of an upper housing part 1 and a lower housing part 2. The housing parts 1, 2 are made of insulating material, preferably of fiber-reinforced plastic with a high CTL value, for example polyamide (PA), PPT(A), PBT or PPT. At least two contact lugs 3 protrude, opposite one another, preferably from the lower housing part 2 and serve for the electrical connection to the circuit or consumer to be short-circuited or earthed. The control for triggering the device takes place via the control lines 4, which are sealed in the upper housing part 1. The housing parts 1, 2 are connected by means of screws 5.

In the exploded view of Fig. 2, the seal 12 can be seen, which is clamped between the upper housing part 1 and the lower housing part 2. The contact lugs 3 located outside the lower housing part 2 continue inside the lower housing part 2 in contact surfaces 6, which are preferably oriented parallel to the longitudinal axis of the housing 1, 2 and which, together with the contact lugs 3, form the electrical contact elements. The contact surfaces 6 are fixed at a distance from one another inside the lower housing part 2, so that no continuous circuit is formed. The material for the Contact elements 3, 6 are preferably made of copper, stainless steel or combinations thereof.

In the event of an emergency, the circuit between the contact surfaces 6 is closed by an electrically conductive connecting element 7 accommodated in the upper part 1 of the housing, which is preferably made of a copper material with the highest conductivity, e.g. Cu-ETP. During normal operation of the circuit or consumer, the connecting element 7 is in a standby position without contact with the contact surfaces 6, which corresponds approximately to the position shown in Fig. 2 and in which the contact elements 3, 6 are insulated from one another. In an emergency, the connecting element 7 is moved into an operational position and is preferably held in this position in a self-locking manner, in which it contacts the contact surfaces 6 of both contact elements 3, 6 and thus an electrically conductive connection is established between the contact elements.

The displacement of the connecting element 7 from the standby position to the operational position is brought about by a pyrotechnic trigger arrangement which can be triggered via the control lines 4 and which preferably acts on the connecting element 7 via a piston 8. The piston 8 is slidably accommodated in a recess in the upper housing part 1, preferably provided with a sealing ring 9. The gas pressure when a propellant charge 10 is ignited in the recess in the upper housing part 1 presses the piston 8 onto the connecting element 7 and further moves it together with it towards the contact surfaces 6. The propellant charge 10 can be fixed in the upper housing part 1 by pouring it into its plastic material, by gluing it in, or the like. The propellant charge 10, advantageously including the connection of the control lines 4, is preferably cast in it using a different material than that of the housing 1, 2. At most, the connecting element 7 itself is designed as a piston, at least at its end closest to the propellant charge 10, and the propellant charge 10 acts directly on it.

In order to prevent the contact elements 3, 6 from being accidentally contacted by the connecting element 7, at least one retaining part 11 inside the housing 1, 2 projects with at least a portion of its cross section into the path of the connecting element 7 as it moves from the standby position to the use position. The dimensions of the elements 7 and 11 are selected such that the connecting element 7 remains safely insulated from the contact arrangements 3, 6. Until the described displacement of the connecting element 7 from the standby position into the use position, the retaining part 11 advantageously holds the connecting element 7 fixed directly in the standby position in which it is spaced from the contact elements 3, 6 and insulated from them.

The retaining part 11 is preferably made of electrically insulating material, for sufficient mechanical strength for fixing the connecting element 7 preferably from plastic with a high CTI value, from polyamide (PA), from PPT(A), PBT or PTT, with or without fiber reinforcement. Alternatively or additionally, the retaining part 11 can be positioned and mounted in the housing 1 in such a way that it is electrically insulated from all conductive structures, either by an appropriate distance from these structures and/or by intermediate layers made of an insulating material. In any case, the retaining part 11 is installed insulated at least from the contact arrangements 3, 6 and it can optionally be provided with an electrically insulating coating, which in certain cases allows the mechanically stabilizing parts of the retaining part 11 to be made from metal or other electrically conductive materials.

The retaining part 11 is preferably designed as a pin-shaped element with a widened end directed towards the connecting element 7 or directly touching it. This end region could be made of electrically insulating material and possibly placed on a pin-shaped section, which could also be made of electrically conductive material if appropriately spaced from other electrically conductive elements of the switching device. The pin-shaped section, which extends from the widened end of the retaining part 11, is preferably embedded in the material of the housing lower part 2 parallel to the contact surfaces 6 in the area between the contact elements 3, 6 and is thus fixed therein. The fixing can be done by gluing, pressing in, screwing or any other suitable fastening method.

In the longitudinal section of Fig. 3 through the embodiment of the emergency switching device according to the invention already shown by way of example in Figs. 1 and 2 and described above, the arrangement of the components and assemblies described above is shown in an assembled, operational state, especially with the connecting element 7 in the ready position. Here it can also be seen that the connecting element 7 can preferably be displaced along a straight path, preferably along the longitudinal axis of the housing 1, 2, which is vertical here.

It is also possible to rotate or pivot the connecting element 7 about an axis lying transversely to the connecting line of the contact surfaces 6 or to guide it on a curved path to the contact surfaces 6. For this purpose, the connecting element 7 can be attached or designed at the end of a tongue or a lever firmly connected to the housing 1, 2. In the course of pivoting or any other movement from the standby position to the use position. According to another embodiment of a switching device according to the invention, it is provided that the at least one further contact element 3, 6 in the standby position is arranged downstream of the contact surface 6 of the first contact element 3, 6 in the direction of rotation at at least a predeterminable angular distance.

In Fig. 3, the preferred design of the connecting element 7 as a sleeve-shaped component, i.e. as a hollow cylinder with an end face facing the piston 10, can already be seen. Alternatively, the connecting element 7 could also be designed as a solid cylinder. The piston 8 can be connected to the connecting element 7 via a pin 13, which is inserted into a bore 15 in the end wall of the connecting element 7 and fixed there.

The retaining part 11 is, as can also be clearly seen in Fig. 3, fixed in the housing lower part 2, preferably inserted in a housing pin 16 extending towards the connecting element 7, whereby this can be done by inserting, gluing or pressing the pin-shaped, narrow section of the retaining part 11 into a bore of the housing pin 16 or by casting.

In both variants for the connecting element 7 mentioned above, slots 14 are preferably worked out, which in the illustrated embodiment and in Fig. 4 are even more clearly visible, are worked out in the wall of the connecting element 7. With these slots 14, the connecting element 7 in its use position encompasses the inner sections of the contact surfaces 6, preferably on both sides, and thus establishes the electrically conductive connection between the two contact elements 3, 6. Preferably, the clear width of the slots 14 is smaller than the thickness of the contact elements 3, 6 in the area of the contact surfaces 6. This preferably includes the thickness including any surface coatings and/or oxide layers. The connecting element 7 is therefore designed in relation to the contact surfaces 6 in such a way as to cause a shearing off of any surface coating or oxide layer formed on the contact surfaces 6 and thus ensure optimal electrical contact. The resulting molding of the connecting element 7 onto the contact surfaces 6 also achieves a holding effect that securely and irreversibly fixes the connecting element 7 in the position of use.

Clearly visible in Fig. 4 is the preferred embodiment of the retaining part 11 as a pin-shaped element with a widened end, with which it rests on the connecting element 7. The longitudinal extension of the retaining part 11 is aligned parallel to the contact surfaces 6 and the retaining part 11 is arranged, at least in the standby position, in the area between the contact elements 3, 6.

The widening of the retaining part 11 is preferably formed by four orthogonal tongues 17 projecting perpendicularly to the longitudinal extension of the retaining part 11. The retaining part 11 is oriented in such a way that the tongues 17 engage in those circumferential sections of the connecting element 7 that are free of slots 14. This can be clearly seen in Fig. 5, in which only the retaining part 11 and the seal 12 with their recesses for the contact elements 3, 6 are shown, since the tongues 17 must also lie circumferentially outside the area of the contact surfaces 6.

In the course of the displacement of the connecting element 7 into the deployment position after triggering the pyrotechnic arrangement with the propellant charge 10, the tongues 17 can, depending on the specific elasticity of the tongues 17 and the mechanical strength of the retaining part 11, preferably be elastically deformed, wherein they then rest against the inside of a hollow connecting element 7 and, due to the frictional forces, cause a holding effect which holds the connecting element 7 in the deployment position.

However, embodiments are also possible in which the retaining part 11 is destroyed, either completely broken or by breaking off the tongues 17. An irreversible deformation of the retaining part 11 could also be provided, as well as pushing away into the material of the housing lower part 2, possibly destroying the housing lower part 2 itself.

In order to always ensure the correct circumferential alignment of the connecting element 7 and the retaining part 11, an anti-twisting device can preferably be provided between the piston 8 or connecting element 7 and the recess in the upper housing part 1 that accommodates these components, for example by means of guide grooves and ridges.

A further embodiment provides that a resistor is integrated in order to prevent too rapid a discharge or too strong current and/or voltage peaks and the secondary damage caused thereby when the connection between the contact elements 3, 6 is closed by the connecting element 7.

Fig. 6 finally shows a perspective, partially schematic side view of the contact arrangements of a further embodiment of an emergency switching device according to the invention. A first of these pairs of contact arrangements, which belong together, comprises, for example, two contact surfaces 6 which are at the same potential and are located inside the housing 1, 2 - not shown here - and which are integrally or at least electrically conductively connected to at least one contact lug 3 each guided to the outside of the housing 1, 2. The second contact arrangement of the pair consists of at least one contact lug 3 arranged on the outside of the housing 1, 2, which is connected to an adjoining and electrically conductive line section 19. In turn, a connecting element 7 which is as electrically conductive as possible is connected to this line section 19. As in the other embodiments of the invention, this can be mechanically held in the standby position by the retaining part 11, here fixed and insulated at a distance from the contact surfaces 6 of the first contact arrangement 3, 6. Instead of a schematically indicated electrical line in the form of conductor wires, possibly in an elastic design, the electrically conductive connection between the or each contact lug 3 of the second contact arrangement and its connecting element 7 could also be formed by mutually contacting strips or linings on the inner wall of the guide in the housing 1, 2 for the connecting element 7 and on the outer circumference of the connecting element 7 itself. In addition, a further improvement in the insulation of the contacting arrangements can be achieved if the connecting element 7 in the standby position - as also shown in Fig. 6 - is embedded in an insulating layer 20 at least with its section facing the contacting surfaces 6.

At best, the insulating layer 20 itself can also act as a retaining part and can also be provided as a cover or coating of the contact surfaces 6. During the movement of the connecting element 7 in the use position, again caused by the pyrotechnic trigger, the connecting element 7 pierces the insulating layer 20 or shears it off the contact surfaces 6, so that the electrically conductive connection between the contact lugs 3 via the lines 19, the connecting element 7 and the contact surfaces 6 is again established, and the irreversible mechanical connection between the connecting element 7 and the contact surfaces 6 is ensured.

A further embodiment of the pyrotechnic switching device according to the invention has at least one optical indicator for externally recognizable functional reliability, which indicates an indication of internal damage and thus a possible functional failure of the entire assembly. A preferred variant of such an indicator is at least one pin-shaped element visible from the outside, preferably redundant, which indicates internal damage and a possible functional failure if broken. This makes it possible to check the functionality of the switching device during the assembly process and to reject the entire assembly if these indicators break.

Reference symbol list

Housing top

Housing base

Contact flag

Control line

Screw

Contact surface

Connecting element piston

Poetry

Propellant charge

Retaining part

Housing seal

cone

slot

Drilling

Housing pin

Tongue

Recess

Line section

Insulating layer

Claims

Patent claims

1. Electrical emergency switching device, comprising a dust- and liquid-tight housing (1, 2) made of insulating material, at least one electrically controllable pyrotechnic trigger (8, 9, 10), at least one pair of associated contact arrangements (3, 6), each with at least one contact lug (3) arranged on the outside of the housing, and at least one contact surface (6) located inside the housing for each contact arrangement, wherein the contact surfaces (6) of each pair of contact arrangements are spaced apart from one another and electrically insulated at least in a standby state of the switching device, further comprising an electrically conductive connecting element (7) inside the housing, which has a standby position and a self-locking use position, wherein the connecting element (7) only contacts the contact surfaces (6) of both contact arrangements of associated pairs in the use position and thus an electrically conductive connection is established within the pair of contact arrangements (3, 6), and wherein the Connecting element (7) can be moved from the standby position into the deployment position by the pyrotechnic trigger (8, 9, 10), further comprising at least one retaining part (11) inside the housing (1, 2) which is electrically insulated from the contacting surfaces (6) or made of insulating material and which projects with at least a partial area of its cross section into the path of the connecting element (7) during its movement from the standby position into the deployment position and thus keeps the connecting element (7) insulated from the contacting arrangements (3, 6) and is designed in such a way that it is destroyed, deformed or pushed away exclusively in the course of a pyrotechnically induced movement of the connecting element (7) from the standby position into the deployment position, characterized in that the retaining part (11) is designed as a pin-shaped element with a widened end and is parallel to the contacting surfaces (6) in the area between the contact elements (3, 6) with its pin-shaped section in the lower part of the housing (2) and is electrically insulated at least from the contacting arrangements (3, 6) by an appropriate distance and/or by intermediate layers made of an electrically insulating material.

2. Switching device according to claim 1, characterized in that the retaining part (11) is electrically insulated from the connecting element (7) by an appropriate distance and/or by intermediate layers made of an insulating material.

3. Switching device according to claim 1 or 2, characterized in that the retaining part (11) which is electrically insulated from the contacting surfaces (6) or made of insulating material rests on the connecting element (7) in the standby position and thus keeps the latter in the standby position and the contacting arrangements insulated, wherein the retaining part (11) preferably has a widening which projects perpendicularly to its longitudinal extent and which engages the connecting element (7), wherein the widening is preferably formed by four orthogonal tongues (17) which project perpendicularly to the longitudinal extent of the retaining part (11).

4. Switching device according to claim 3, characterized in that slots (14) for engaging around the contact surfaces (6) of the contact elements (3) are worked out in the connecting element (7), and that the tongues (17) engage in those circumferential sections of the connecting element (7) which are free of slots (14) and are located circumferentially outside the region of the contact surfaces (6).

5. Switching device according to one of claims 1 to 4, with at least one pair of associated contacting arrangements (3, 6) consisting of at least one contacting surface (6) located inside the housing and at least one contact lug (3) guided to the outside of the housing, the contacting surfaces (6) of each pair of contacting arrangements being spaced apart from one another inside the housing (1, 2), the connecting element (7) in the standby position touching a maximum of one of the contacting surfaces (6) of the pair of contacting arrangements (3, 6) and being spaced apart and/or insulated from the other contacting surfaces of the associated pair by the retaining part (11) which is electrically insulated from the other contacting surfaces (6) of the pair or is made of insulating material.

6. Switching device according to one of claims 1 to 5, with at least a first contact arrangement consisting of at least one contact surface (6) located inside the housing and at least one contact lug (3) guided to the outside of the housing, with at least a second contact arrangement (3, 7, 19) consisting of at least one contact lug (3) arranged on the outside of the housing (1, 2), a line section (19) electrically connected thereto and a connecting element (7) electrically connected thereto, the first and second contact arrangements forming a pair belonging together, the connecting element (7) being held at a distance and/or insulated from the contact surface (6) of the first contact arrangement (3, 6) in the standby position by the retaining part (11) which is electrically insulated from the contact surfaces (6) or made of insulating material.

7. Switching device according to one of claims 1 to 6, characterized in that the connecting element (7) in the standby position is embedded in an insulating layer (20) at least with its section facing the contacting surfaces (6) or the contacting surfaces (6) are covered by an insulating layer (20), and the connecting element (7) in the use position has pierced the insulating layer (20).

8. Switching device according to one of claims 1 to 7, characterized in that the connecting element (7) is movable along a straight path, preferably along a longitudinal axis of the housing (1, 2).

9. Switching device according to one of claims 1 to 8, characterized in that the connecting element (7) is mounted on an axis relative to the contact elements (3, 6) in the housing (1, 2) so as to be rotatable or pivotable along a curved path, and the at least one further contact element in the standby position is arranged downstream of the contact surface (6) of the first contact element in the direction of rotation at at least one predeterminable angular distance.

10. Switching device according to one of claims 1 to 9, characterized in that the connecting element (7) is guided relative to the housing (1, 2) by means of an anti-twist device.

11. Switching device according to one of claims 1 to 10, characterized in that the connecting element (7) is rotatably mounted on an axis relative to the contact elements (3, 6) in the housing (1, 2) and the at least one further contact element (3, 6) in the standby position is arranged downstream of the contact surface (6) of the first contact element (3, 6) in the direction of rotation at at least one predeterminable angular distance.

12. Switching device according to one of claims 1 to 11, characterized in that the pyrotechnic trigger (8, 9, 10) comprises an electrically ignitable propellant charge (10) and a piston (8) displaceable in the housing (1, 2) by the action of the propellant charge (10), which piston (8) acts directly or indirectly on the connecting element.

13. Switching device according to claim 12, characterized in that the propellant charge (10) including the connection of the control lines (4) is cast with a different material than that of the housing (1,2).

14. Switching device according to one of claims 1 to 13, characterized in that the connecting element (7) is designed to cause a shearing off of any surface coating or an oxide layer formed on the contacting surfaces (6).

15. Switching device according to claim 14, characterized in that slots (14) are formed in the connecting element (7), the inner sides of which contact the contacting surfaces (6) of the contact elements on opposite sides in the insert position.

16. Switching device according to claim 15, characterized in that the connecting element (7) is designed as a cylinder or open sleeve open towards the contact elements (3, 6).

17. Switching device according to claim 15, characterized in that the clear width of the slots (14) of the connecting element (7) is smaller than the thickness of the Contact elements (3, 6) in the region of the contacting surfaces (6), possibly including surface coatings and/or oxide layers.

18. Switching device according to one of claims 1 to 17, characterized in that it is arranged and rests with the widened end on the connecting element (7) in its ready position.

19. Switching device according to one of claims 1 to 18, characterized in that at least one contact arrangement of each pair is connected to a resistor and preferably additionally to a heat accumulator.