DE102008002136B3 - Mechanical adjusting movement activation device i.e. pyrotechnic tripping device, for e.g. rollover protection system, in motor vehicle, has piston moved from resting to action position when cylinder is loaded with fluid pressurizing medium - Google Patents

Abstract

The device has a guiding cylinder (3), and a piston (4) moved in the guiding cylinder from a resting position into an action position by expanding reaction gases of an actuator (1). A guiding cylinder (6) is provided with a controlling piston (7), where the piston (4) is moved from the resting position to the action position by the piston (7) when the guiding cylinder (6) is loaded with a fluid pressurizing medium. The guiding cylinder (6) is arranged behind the guiding cylinder (3), and divided into an ignition chamber (2) and a test chamber (8) with a pressure medium connection (9).

Description

The The invention relates to a device for triggering a mechanical adjusting movement by means of a pyrotechnic actuator with an ignition chamber, a guide cylinder, a piston and one outwards out Piston rod as an effective actuator, the piston in the guide cylinder from the expanding reaction gases of the actuator from a rest position is displaceable in an action position.

such Devices are used when mechanical processes are triggered and when it comes to extremely short reaction times.

pyrotechnic propellants be in vehicles for a long time as standard in so-called airbags used. They are detonated if dangerous from sensors Acceleration values are determined, and then generate abruptly a big Reaction gas volume for filling of pillow-like balloons, between the motor vehicle occupants and body parts are clamped to the risk of injury to reduce.

Such propellant charges have also long been used in other active safety components in motor vehicles, such as extendable rollover protection systems and displaceable hoods (see eg. DE 43 42 401 A1 . DE 10 2006 034 726 A1 ). Of course, such components must be checked for reliability before their standard use. Even after installation and during its service life, test releases must be feasible.

there results in the fundamental Problem that the functional safety can only be checked if the pyrotechnic fuze is activated. After each test release must not just the spent detonator expanded and replaced by a new one, but also the entire, at the ignition soiled trip unit. It must extensive precautions are taken to prevent accidental ignition avoid and while The examination reactivate shutdown electronic devices.

In the DE 100 27 753 C1 a rollover protection system for motor vehicles is described in which a sensor-controlled activatable pyrotechnic element for releasably actuating the holding mechanism of a rollover protection body is used. To overcome the above-described problem it is proposed, in addition to the pyrotechnic element, to provide a second actuator, which does not consume during a release, for actuating the holding mechanism.

In order to is indeed a possibility created the function of the holding mechanism without triggering the pyrotechnic igniter to check. The actual, outward acting actuator of the pyrotechnic actuator remains but unchecked, because only one acting parallel to the Funktionsaktuator Prüfaktuator is provided, which triggers a replacement movement, without that you can be sure that even the actual actuator the Funktionsaktuators is operable and not in the associated guide cylinder is stuck or missing.

This is considered to be a serious deficiency of the known test release.

It Thus, the task is over the lifetime of the devices seen multiple times necessary test releases enable, without the pyrotechnic actuator must be ignited and without that Parts of the system remain unchecked.

to solution the task is for the apparatus described above proposed according to the invention, that a second guide cylinder with test tube is provided, and that the piston from the test piston from the rest position in the action position is displaced when the second guide cylinder is acted upon by a fluid pressure medium.

at Such a device will be all functionally important parts moved during the test release, without the pyrotechnic igniter must be consumed. This is a significant shortcoming of the known Device overcome and a functional check that meets all requirements allows.

In Further development of the inventive idea is provided that the second guide cylinder As seen in the direction of adjustment is arranged behind the first guide cylinder and from the test piston in an ignition chamber and a test chamber is divided sealingly with pressure medium connection. It is further provided that the test piston in its initial position with a first piston rod part the rear seen in the direction of adjustment End wall of the second guide cylinder and abuts with a second piston rod part on the piston itself.

According to an alternative embodiment of the inventive concept it is provided that the second guide cylinder is arranged in the direction of adjustment in front of the guide cylinder and that the test piston is connected via a first piston rod part with the piston and with a second piston rod part, the front end wall of the two th guide cylinder penetrates, with the proviso that the second piston rod part forms the outward-acting actuator. In this embodiment, it is provided that the piston and the test piston are moved together in the direction of adjustment when the pyrotechnic actuator is ignited.

The at the ignition of a pyrotechnic actuator resulting reaction gases reach very high pressures, so that to generate outward restoring forces only relatively small piston cross sections are needed. For testing purposes disposal standing pressures in workshops are in contrast much lower, so that to achieve the same restoring forces larger piston cross sections required are. Larger piston cross sections are in the device according to the invention readily realizable. It has proven to be expedient if the effective piston area of the test piston significantly larger, preferably at least twice as big like the effective piston area of the pyrotechnic piston acted upon.

The inventive device can also in usual Way complemented by a return spring, from the outside acting actuator is acted upon in Gegenstellrichtung.

The inventive device can also be modified so that from the outside acting Actuator is a mechanical actuator movable, in turn from a return spring is charged.

The inventive device can be used in active rollover protection systems, with actively liftable bonnets and other safety components be applied in motor vehicles where it is responsive solution a holding device arrives.

Further details and advantages are given in the 1 to 5 illustrated embodiments explained in more detail.

It demonstrate:

1 a pyrotechnic actuator at rest,

2 a pyrotechnic actuator in pyrotechnic triggered action position,

3 a pyrotechnic actuator in triggered by means of test piston action position,

4 an alternative embodiment to 1 at rest,

5 the embodiment according to 4 in action position.

The in 1 illustrated pyrotechnic actuator 1 includes an ignition chamber 2 , a guide cylinder 3 and a piston guided therein 4 , whose outwardly guided piston rod as a mechanical actuator 5 is effective.

The actuator 5 can - as shown - for example, with a pivoting latch 13 to act as a mechanical actuator, in turn, by a return spring 12 is held in its initial position. In dashed line position, the pivoting pawl 13 for example, a locking pin 14 release.

To the functionality of the pyrotechnic actuator 1 to be able to check is according to the invention coaxial with the guide cylinder 3 a second guide cylinder 6 with test piston 7 intended. Here is the test piston 7 arranged so that he has the piston 4 of the pyrotechnic actuator can shift from the rest position to the action position when the second guide cylinder 6 is acted upon by a fluid pressure medium.

In the in 1 illustrated embodiment, the second guide cylinder 6 seen in the direction of adjustment behind the first guide cylinder 3 arranged and from the test piston in an ignition chamber 2 and a test chamber 8th with pressure medium connection 9 subdivided. The test piston 7 is in its initial position with a first piston rod part 7a at the rear end wall seen in the direction of adjustment 10 of the second guide cylinder 6 and with a second piston rod part 7b on the piston 4 at.

In 2 is the pyrotechnic actuator 1 according to 1 shown without the external mechanical environment. piston 4 and the outwardly guided piston rod as an effective actuator 5 are shown displaced from the rest position to the action position after ignition of the pyrotechnic actuator. It arises in the ignition chamber 2 a high pneumatic pressure, by which the piston - also against external restoring forces - is shifted into the action position. The test piston 7 remains unchanged in its initial position.

In 3 is the pyrotechnic actuator according to 1 after completing a test trip. This is done via the pressure medium connection 9 from an external pressure medium source, a pressure medium in the test chamber 8th initiated, causing the test piston 7 - In the presentation - is shifted from its initial position to the right while doing the piston 4 from his resting position into his action position. Will the test chamber 8th subsequently ventilated, become pistons 4 and test pistons 7 moved back from the outer return means to its original position.

In the embodiment according to 4 is provided that the second guide cylinder 6 in the direction of adjustment in front of the guide cylinder 3 is arranged. The test piston 7 is about a piston rod part 7c with the piston 4 connected while a second piston rod part 7d the front end wall 11 of the second guide cylinder 6 penetrates, with the proviso that the second piston rod part 7d the outward acting actuator 5a forms. The ignition chamber 2 the pyrotechnic actuator 1 is in 4 to the left of the piston 4 arranged. Incidentally, the reference numerals denote the same parts as in the previously described illustrations.

In 5 is the embodiment according to 4 presented in action position. When triggered, the pyrotechnic actuator causes in the ignition chamber 2 resulting pressure that the piston 4 together with the piston 7 is moved to the right in the displayed action position. This causes the piston rod part 7d as an external effective actuator 5a the adjustment of an external, connected mechanical actuator.

The same movement can be achieved if via the pressure medium connection 9 the test chamber 8th is acted upon by a fluid pressure medium. Also in this case, both interconnected pistons in the in 4 shown action position postponed. By means of the restoring forces of the outer mechanics, the interconnected pistons can move into the in 4 shown rest position are pushed back.

The inventive device of triggering a mechanical adjusting movement has the advantage that the test piston 7 in comparison to the piston 4 can be designed with a significantly larger cross-sectional area, so that can be used for test triggering normally used in workshops pressure fluid sources, which generally do not provide as high fluid pressures, as they are achieved in the release of a pyrotechnic actuator. The test firings can be repeated as often as required, without the ignition material of the pyrotechnic actuator having to be consumed.

The device according to the invention has the further advantage that ignition chamber 2 and test chamber 8th through the piston 7 or the piston 4 separated from each other gas-tight, so that the test chamber 8th can be acted upon by any fluid pressure medium, without this in the ignition chamber 2 can penetrate. It is not required the test chamber 2 to the outside - for example, by a check valve in the pressure medium connection - hermetically complete or make a complete removal of the pressure medium after a test trip. The ignition chamber 2 In no case is "non-pressurized" pressurized.

at pyrotechnic triggering the systems can only be reactivated after using a new propellant. To force the user of the vehicle to a workshop visit the requirement is made that the triggered actuating movement is irreversible, in other words, that the device is not without expert Help can be brought to the starting position. This can - in addition to the inventive idea be reached when the piston in pyrotechnic release by Deformation is irreversibly positioned and thus a mechanical Lock against the provision of the device.

Finally is It should also be noted that a purely mechanical test is also required can, by arranging a second, outwardly guided piston rod, with which the piston is movable.

1

pyrotechnic actuator

2

ignition chamber

3

guide cylinder

4

piston

5

actuator

5a

actuator

6

guide cylinder

7

test tube

7a to 7d

Piston rod part

8th

test chamber

9

Pressure medium connection

10

end wall

11

end wall

12

Return spring

13

mechanical actuator

14

locking pin

Claims (11)

Device for triggering a mechanical adjusting movement by means of a pyrotechnic actuator ( 1 ) with - a firing chamber ( 2 ), - a guide cylinder ( 3 ), - a piston ( 4 ) and - an outwardly guided piston rod as an effective actuator ( 5 ), the piston ( 4 ) in the guide cylinder ( 3 ) of the expanding reaction gases of the actuator ( 1 ) is displaceable from a rest position into an action position, characterized in that a second guide cylinder ( 6 ) with test piston ( 7 ) is provided and that the piston ( 4 ) from the test piston ( 7 ) is displaceable from the rest position into the action position when the second guide cylinder ( 6 ) is charged with a fluid pressure medium. Apparatus according to claim 1, characterized in that the second guide cylinder ( 6 ) seen in the direction of adjustment behind the first guide cylinder ( 3 ) is arranged and from the test piston ( 7 ) in an ignition chamber ( 2 ) and a test chamber ( 8th ) with pressure medium connection ( 9 ) is sealingly divided. Apparatus according to claim 1 or 2, characterized in that the test piston ( 7 ) in its initial position with a first piston rod part ( 7a ) at the rear end wall seen in the direction of adjustment ( 10 ) of the second guide cylinder ( 6 ) and with a second piston rod part ( 7b ) on the piston ( 4 ) is present. Apparatus according to claim 1, characterized in that the second guide cylinder ( 6 ) seen in the direction of adjustment in front of the guide cylinder ( 3 ) and that the test piston ( 7 ) via a first piston rod part ( 7c ) with the piston ( 4 ) and with a second piston rod part ( 7d ) the front end wall ( 11 ) of the second guide cylinder ( 6 ) penetrates, provided that the second piston rod part ( 7d ) the outwardly acting actuator ( 5a ). Device according to claim 4, characterized in that the piston ( 4 ) and the test piston ( 7 ) are moved together in the direction of adjustment when the pyrotechnic actuator ( 1 ) is ignited. Device according to one of claims 1 to 5, characterized in that the effective piston area of the test piston is at least twice as large as the effective piston area of the piston ( 4 ). Device according to one of claims 1 to 6, characterized in that the outwardly acting actuator ( 5 . 5a ) in the opposite direction of a return spring ( 12 ) is acted upon. Device according to claim 7, characterized in that the actuator ( 5 . 5a ) a mechanical actuator ( 13 ) is movable, which in turn by a return spring ( 12 ) is acted upon. Device according to one of claims 1 to 8, characterized that the piston in pyrotechnic release by plastic deformation irreversible is positioned. Device according to the preamble of claim 1, with the proviso that the piston ( 4 ) for testing purposes purely mechanically via a second, outwardly guided piston rod is movable. Application of the device according to claims 1 to 10 in rollover protection systems, active bonnets or other safety components in motor vehicles, in which a holding device or the like are solved pyrotechnically got to.