EP2081208B1 - Pyromechanical dividing device - Google Patents

Abstract

The device (10) has a housing (12) forming a pressure chamber (40), and two separator pistons (44) arranged in the pressure chamber. The separator pistons are moved in different directions during impact with a pressure impulse relative to the housing to separate current conductors (14) arranged in the housing. The pressure impulse is produced by a pyromechanical drive element (20), where the pyromechanical drive element and the separator pistons are extended in a plane. The separator pistons form an angle with the plane, and comprise a separation tool (48) for separating an electrical circuit.

Description

The invention relates to a pyromechanical separation device.

Pyromechanical separators are well known and typically include a housing forming a pressure chamber and a separator piston disposed in the pressure chamber that is movable relative to the housing upon application of a pressure pulse generated by a pyrotechnic driver to sever a conductor disposed within the housing.

A pyromechanical separating device having a housing forming a pressure chamber and a separating piston disposed in the pressure chamber, which is movable relative to the housing upon application of a pressure pulse generated by a pyrotechnic driving element to sever two conductors arranged in the housing, is known from US 5,156,074 FR-A-2 775 539 known.

Such pyromechanical separation devices are used for example in motor vehicles to disconnect an electrical system from the vehicle battery in an accident. The pyromechanical separation devices may be connected for this purpose with a central control unit (ECU), which in addition with at least one safety device, such as a belt tensioner and / or an airbag, in conjunction and which in an accident, an electrical release signal to the drive element of the pyromechanical separation device and transmitted to the at least one safety device.

Modern motor vehicles not only have a large number of to-be-controlled safety devices for personal protection, but may also comprise a plurality of separate electric circuits, for example in a hybrid drive technology and / or to provide a start / stop functionality in an accident respectively a pyrotechnic separator must be interrupted or disconnected from a power source.

The problem here is that a central control unit provided for controlling the safety devices and the pyrotechnic isolators usually has a limited number of control outputs, which may not be sufficient to handle all the safety devices, e.g. Airbags and belt tensioners, as well as all pyrotechnic separating elements to be able to control.

In principle, there is the possibility of solving this problem by using a central control unit which has a larger number of control outputs. However, due to the associated additional costs, this solution is not attractive for motor vehicle manufacturers.

The invention has for its object to enable the transection of a number of circuits, which is greater than the number of available control outputs of a central control unit.

To solve the problem, a pyromechanical separation device with the features of claim 1 is provided.

The separating device according to the invention has a housing forming a pressure chamber and at least two separating pistons arranged in the pressure chamber, which are movable relative to the housing when acted upon by a pressure pulse generated by a pyrotechnic drive element to sever at least two arranged in the housing conductor.

The invention is thus based on the general idea of severing a plurality of current conductors by means of a single pyromechanical separation device and in particular by means of a single drive charge, and thus interrupting a plurality of circuits.

According to the invention, the separating device provides at least two separating pistons, which require only a pyrotechnic driving element and, for driving, only a single control output on a control unit provided for triggering the separating device.

For example, if the control unit has eight control outputs, seven of which are already used to control safety devices, such as those shown in FIG. Airbags and / or belt tensioners are occupied, the last remaining control output can be used to cut with the aid of the separation device according to the invention two or more circuits, i. the central control unit does not need to have a corresponding number of free control outputs.

By means of the separation of a plurality of conductors according to the invention by means of a single separator, material costs, such as e.g. Expenses for additional power cables and connectors, which would be required for triggering and activation of additional separation devices, as well as corresponding installation costs saved, which would be incurred if a separate separation device would have to be controlled to cut through each power line.

The separator according to the invention further has a compact design and is at most insignificantly larger than a conventional disconnecting device for interrupting a single circuit.

Advantageous embodiments of the invention are described in the dependent claims, the description and the drawings.

According to a preferred embodiment, the separating pistons are movable in different directions. This is made possible by the propagation of a pressurized gas released by the drive element into an area located at least partially between the separating pistons, preferably a central region of the pressure chamber, whereby a particularly efficient admission of the separating pistons and thus a particularly rapid and reliable severing of the conductors is achieved.

Depending on the available installation space and / or the number of current conductors to be cut through, at least two of the separating pistons can be movable in opposite directions and / or at least two of the separating pistons can be moved transversely to one another.

To achieve a compact design as possible, the drive element and the separating piston preferably extend in a plane. For example, the separating piston and the drive element can be arranged in a T-shape, with the separating pistons extending in one direction, while the drive element is oriented at right angles thereto. In principle, however, a Y-shaped arrangement of the separating piston and the drive element is conceivable. In addition, a drive element and three separating pistons can be arranged crosswise or X-shaped or arrange a drive element and more than three separating pistons in a star shape, so that a correspondingly higher number of separating pistons can be acted upon by a single pyrotechnic drive element and a corresponding one Number of circuits can be interrupted by means of a single separator.

According to an alternative embodiment, at least one of the separating pistons forms an angle with a plane defined by the driving element and another separating piston. By such a three-dimensional arrangement of drive element and separating piston, the number of acted upon by a single pyrotechnic drive element separating piston and thus also the number of interruptible by the circuit breaker circuits can be further increased. Thus, with an exclusively rectangular arrangement of the drive element and of all separating pistons, five separating pistons can be driven by the drive element.

In order to ensure the fastest possible and reliable interruption of the circuits, each separating piston preferably has a cutting bit for cutting through a corresponding current conductor.

The number of circuits to be interrupted by the disconnecting device can be further increased if at least one of the separating pistons has at least two separating tools for cutting through a number of conductors corresponding to the number of separating tools.

An even faster and more reliable separation of the conductors is also achieved if they each have a separation point at which the conductors have a reduced strength.

To solve the problem, a separation device according to claim 9 is further provided by which by means of a single pyrotechnic Drive elements also cut through several conductors and thus achieve the mentioned advantages.

Fig. 1

eine perspektivische Ansicht einer erfindungsgemäßen Trennvorrichtung gemäß einer ersten Ausführungsform;

Fig. 2

eine Querschnittsansicht der Trennvorrichtung von Fig. 1;

Fig. 3

einen Ausschnitt einer Querschnittsansicht einer erfindungsgemäßen Trennvorrichtung gemäß einer zweiten Ausführungsform;

Fig. 4

eine Querschnittsansicht einer erfindungsgemäßen Trennvorrichtung gemäß einer dritten Ausführungsform; und

Fig. 5a bis c

schematische Darstellungen der Trennvorrichtung von Fig. 1 mit verschiedenen, durch die Trennvorrichtung zu unterbrechenden Stromkreisen.

The invention will be described below purely by way of example with reference to advantageous embodiments with reference to the accompanying drawings. Show it:

Fig. 1

a perspective view of a separating device according to the invention according to a first embodiment;

Fig. 2

a cross-sectional view of the separator of Fig. 1 ;

Fig. 3

a detail of a cross-sectional view of a separating device according to the invention according to a second embodiment;

Fig. 4

a cross-sectional view of a separating device according to the invention according to a third embodiment; and

Fig. 5a to c

schematic representations of the separation device of Fig. 1 with various circuits to be interrupted by the disconnecting device.

In Fig. 1 and 2 is a first embodiment of a pyromechanical separation device 10 for substantially simultaneous interruption of two circuits 70, 72 (FIG. Fig. 5 ). The separation device 10 comprises a housing 12 in which two rail-like current conductors 14 are arranged, which are each formed from a multi-folded sheet metal strip 16. In the region of their ends, the sheet metal strips 16 each have a connecting piece 18, which allows an electrical connection of the current conductor 14 to a respective circuit 70, 72.

In the housing 12, a pyrotechnic drive element 20 is further arranged, which comprises a space containing a pyrotechnic fuel or fuel space portion 22, which points into the interior of the housing 12. At its rear side remote from the installation space section 22, the drive element 20 further comprises a contacting section 24, which projects at least partially out of the housing 12 and which connects the electrical connection of the drive element 20 to a control unit 68 (FIG. Fig. 5 ) to trigger the separator 10 allows.

The drive element 20 is pressure-tightly connected to the housing 12, for example by acting as in Fig. 2 shown inserted into a recess 26 of the housing 12 and welded or glued in this and additionally secured by sections 28 of the current conductor 14, which engage in corresponding grooves 30 of the drive member 20.

Alternatively, as in Fig. 3 is shown, a nozzle 32 may be formed on the outside of the housing 12, to which the drive element 20 is attached and secured by an encapsulation 34. In order to improve the connection between nozzle 32 and drive element 20, a puncture 36 or an at least partially circumferential groove is provided both on the outside of the nozzle 32 and on the outside of the drive element 20, in which or which encapsulation 34 engages.

The installation space portion 22 of the drive element 20 defines a central portion 38 of a defined by the housing 12 pressure chamber 40. The pressure chamber 40 further comprises two starting from the central portion 38 in opposite directions extending separating piston 42, in each of which a separating piston 44 is slidably mounted.

Each separating piston 44 has a recess 46 on its rear side facing the central section 38, while a separating chisel 48 is formed on the front side of each separating piston 44 facing away from the central section 38, pointing in the direction of a separation point 49 of the current conductor 14 assigned to the separating piston 44.

In a normal or rest position, i. So before triggering the separator 10, the separating piston 44 are each in a rear end position in which they have a minimum distance from each other and a maximum distance from the conductors 14. In their rear end position, the separating pistons 44 abut with their rear sides against the first shoulders 50 of the housing.

Furthermore, each separating piston 44 has, in the region of its front side, a projection 52 which runs around the separating piston circumference and rests on a second shoulder 54 which delimits a circumferential groove 56 which is provided in the housing wall delimiting the respective separating piston section 42.

In the groove 56, a seal is arranged, for example, an O-ring 58, which communicates with the central portion 38 in communication part of the respective separating piston 42 of the pressure chamber 40 against a space 60 between the respective separating piston 44 and the associated Current conductor 14 seals gas-tight substantially. Alternatively, the O-ring 58, as in Fig. 3 is also shown to be disposed between the back of the separating piston 44 and the corresponding first housing shoulder 50.

If the separating device 10 is triggered upon activation of the drive element 20, the fuel located in the installation space section 22 ignites, and the installation space section 22 bursts on its front side facing the central section 38. By the gas released by the reaction of the fuel, in Fig. 3 represented by the arrows 61, a gas pressure builds up in the pressure chamber 40, which acts on the separating pistons 44 in opposite directions and thus in the direction of their respective current conductors 14.

As soon as the gas pressure exceeds a certain threshold value, the projections 52 of the separating pistons 44 are sheared off and the separating pistons 44 are accelerated in the direction of their respective current conductor 14.

By striking the current conductor 14 separating tool 48, the current conductors 14 are shunted at their separation points 49 and the respective circuits interrupted. In order to facilitate the severing of the current conductors 14, the current conductors 14 have a reduced strength at their separation points 49. In addition, the current conductors 14 in the region of the separating points 49 are each supported by a shearing edge 62.

In Fig. 4 a third embodiment of a separating device 10 according to the invention is shown, which is provided for the at least approximately simultaneous severing of four conductors 14 and thus four circuits can interrupt substantially simultaneously.

Like the separation device 10 described above, the in Fig. 4 Separator 10 shown two movable in opposite directions separating piston 44.

In contrast to the separating device 10 described above, however, each separating piston 44 has on its front side two tongue-like cutting tools 48, which are arranged in a plane extending side by side.

Each separating chisel 48 is assigned a separate current conductor 14, so that the separating device 10 comprises a total of four current conductors 14 to be cut through. The four current conductors 14 are mounted in pairs in the housing 12 in such a way that, when the separating pistons 44 impinge on the current conductors 14, each current conductor 14 is severed by one of the separating tools 48.

In contrast to the current conductors 14 of the separator 10 described above, the in Fig. 4 shown conductor 14 is not bent several times, but plan formed. In this case, the current conductors 14 of each pair of current conductors lie in a plane which extends at least approximately at right angles to the plane defined by the separating chisel 48. In order to facilitate the severing of the current conductors 14, these also each have a separation point 49 with reduced strength.

In a further difference from the separator 10 described above, the drive element 20 of the in Fig. 4 shown separating device 10 received in a housing insert 63 which is inserted into the housing 12 and connected substantially gas-tight therewith. The housing insert 63 defines a gas passage 65 through which the gas released by the drive member 20 acts to more efficiently act upon the separating piston 44 is deflected into the recesses 46 of the separating piston 44.

In Fig. 5 Several variants of circuits 70, 72 are shown, which can be interrupted by a separator 10 according to the first embodiment.

So shows Fig. 5a schematically a separator 10 with two movable in opposite directions separating piston, shown by the arrows 64, which can be acted upon by a drive element 20 which is connected by electrical lines 66 to a control unit 68 for activating the separator 10.

As already mentioned, two conducting conductors 14 arranged in the separating device 10 can be cut through by the separating pistons, wherein one current conductor 14 is part of a first circuit 70 which connects one connection point A to one connection point B, while the other current conductor 14 forms part of a second circuit 72 is, which connects a connection point C with a connection point D.

At the in Fig. 5a shown variant, the circuits 70, 72 are electrically isolated from each other. In this case, the circuits 70, 72 may have the same or different potentials or polarities. Upon triggering of the separation device 10 and the resulting separation of the current conductor 14, the connection points A and B of the first circuit 70 on the one hand and the connection points C and D of the second circuit 72 on the other hand are electrically separated from each other.

In Fig. 5b a second circuit variant is shown, which differs from the in Fig. 5a shown variant differs in that in addition the connection points B and D are interconnected. In this variant, both circuits 70, 72 have the same potential and the same polarity. When the disconnecting device 10 is triggered, the connection points A and B and the connection points C and D are separated from one another, whereas the connection points B and D remain connected to one another.

Fig. 5c shows a third circuit variant, which differs from the in Fig. 5b shown second variant differs in that in addition the connection points A and C are electrically connected to each other. In this variant, the circuits 70, 72 also have the same potential and the same polarity. When the disconnecting device 10 trips, the connection points A and B and the connection points C and D are each separated from one another, whereas the connection points A and C on the one hand and the connection points B and D on the other hand remain electrically connected to one another.

LIST OF REFERENCE NUMBERS

10

separating device

12

casing

14

conductor

16

Sheet metal strips

18

connector

20

driving element

22

installation portion

24

contacting section

26

recess

28

Conductor section

30

groove

32

Support

34

encapsulation

36

puncture

38

Central section

40

pressure chamber

42

Separating piston section

44

separating piston

46

recess

48

cutting chisel

49

separation point

50

shoulder

52

projection

54

shoulder

56

groove

58

poetry

60

room

61

gas

62

shearing edge

63

housing insert

64

arrow

65

gas channel

66

management

68

control unit

70

circuit

72

circuit

A

connection point

B

connection point

C

connection point

D

connection point

Claims (10)

1. Pyromechanical separating device (10) with a housing (12) forming a pressure chamber (40) and at least two separating pistons (44) arranged in the pressure chamber (40) which are moveable relative to the housing (12) by means of an impact with a pressure pulse generated by a pyrotechnic drive element (20), to separate at least two current conductors (14) arranged in the housing (12).
2. Separating device (10) according to claim 1,
   characterized in that
   the separating pistons (44) are moveable in different directions.
3. Separating device (10) according to claim 1 or 2,
   characterized in that
   at least two of the separating pistons (44) are moveable into opposite directions.
4. Separating device (10) according to one of the preceding claims,
   characterized in that
   at least two of the separating pistons (44) are moveable crosswise to each other.
5. Separating device (10) according to one of the preceding claims,
   characterized in that
   the drive element (20) and the separating pistons (44) extend across a plane.
6. Separating device (10) according to one of the claims 1 to 4,
   characterized in that
   at least one of the separating pistons (44) forms an angle with a plane defined by the drive element (20) and another separating piston (44).
7. Separating device (10) according to one of the preceding claims,
   characterized in that
   each separating piston (44) comprises a separating chisel (48) for separating a corresponding current conductor (14).
8. Separating device (10) according to one of the preceding claims,
   characterized in that
   at least one of the separating pistons (44) comprises at least two separating chisels (48) for separating a corresponding number of current conductors (14).
9. Pyromechanical separating device (10) with a housing (12) forming a pressure chamber (40) and a separating piston (44) having at least two separating chisels (48), arranged in the pressure chamber (40), which is moveable relative to the housing (12) by means of an impact with a pressure pulse generated by a pyrotechnic drive element (20), to separate a number of current conductors (14), arranged in the housing, corresponding to the number of separating chisels (48).
10. Separating device (10) according to one of the preceding claims,
    characterized in that
    each current conductor (14) includes a point of separation (49) where it has a reduced strength.

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