Function

Functional sequence (The illustrations represent non vehicle-specific principle illustrations.)












1 Depending on the severity of the impact, the restraint systems control module (N2/7) supplies an electric ignition pulse to one or both ignition squibs (R12/13, R12/14) of the gas generator, whereby the ignition of the ignition squibs can take place simultaneously or time-delayed, depending on the type of accident.
2 The ignition squibs ignite the solid fuel in the gas generator, which burns up and so produces a gas which, under high pressure, is directed explosively and via a filter into the air bag, the actual airbag.
3 The folded airbag, located on the gas generator, is inflated and, under pressure of the inflowing gas, breaks through the padding of the steering wheel at a pre-determined breakthrough point.
4 Whilst still expanding, the airbag escapes through the breakthrough point and expands to its max. size.







5 The airbag is fully expanded after approx. 45 ms.
6 Immediately after having reached its full size the pressure in the airbag starts to reduce. The gas escapes from the airbag via filter and the airbag collapses.


NOTE:
Disposal
Even if the type of accident only requires the first stage of the driver airbag, the second stage is ignited within a very short time. This ensures that both stages have been actuated. The airbag can then be disposed of normally.