Driver airbag component description - GF91.60-P-4037RT
MODEL 251 up to Model Year 8
The driver airbag with its squibs (driver airbag ignition squib 1 and driver airbag ignition squib 2) is located in the steering wheel impact absorber. It protects the driver from injuries in the event of a head-on collision.
The driver airbag is bolted to the steering wheel and padded on the side nearest to the driver. The padding is equipped with a predetermined fracture point to enable the airbag to deploy fully.
The electrical connection of the squibs from the rotatable steering wheel to the restraint systems control unit (N2/7) is via the steering column module (N80).
The casing contains the inflator, which is equipped with two acid-free solid fuel units and is connected to the airbag by way of a filter. For ignition, each solid-propellant charge is equipped with its own squib.
Function
The restraint systems control unit sends an electrical ignition pulse to either one or both of the squibs of the gas generator, depending on the severity of the impact. The type of crash involved determines whether the squibs are ignited simultaneously or in stages.
The squibs then ignite the solid propellant in the gas generator. When the solid fuel burns it generates a gas that flows "explosively" under high pressure through a filter and into the interior of the actual airbag.
The folded airbag on the gas generator then inflates, the pressure of the in flowing gas forcing open the steering wheel cover along a predetermined fracture point.
As gas enters the bag, it pushes through the predetermined fracture point and fills to maximum volume.
The airbag reaches its full volume within approximately 30 milliseconds.
The airbag begins to deflate immediately as soon as it has reached its maximum volume. The gas escapes from the airbag through a filter and the airbag collapses.