Functional Description

Functional description

General




SIPS bag is a separate system in each front seat. There is no connection between the SIPS bag in both of the seats. Depending on the collision process the SIPS bag is detonated in the seat on the collision side. The sensor unit has a pyrotechnical impact sensor, which in order to detonate the system, must be hit with a force that gives a speed of 2 m/s against the sensor unit by the deformed door. The limit values are set to avoid unintentional detonation, for example, when the door is hit or minor impact against a stationary object.
The pressure plate deforms the aluminium case, whereby an impact pin is pushed in and triggers the detonator. The detonator generates a pulse which is transferred to the igniter cables as a detonation wave. When the detonation wave reaches the cushion module it activates the charge of powder in the gas generators.
On activation the gas is first blown into a combustion chamber pipe and the gas then flows out into the cushion. Activation of one of the gas generators occurs immediately and the other is activated with a delay of about 3 milliseconds. The delay is set to maintain the inflated cushion's pressure and volume for a sufficiently long time.
On inflation the cushion breaks the cushion module's casing, tears the seat upholstery's seam and is forced out to inflate to full volume. The cushion is inflated in the direction of the door side to contribute toward the protection of the person's chest in the event of a collision. Ventilation through holes in the cushion's fabric is adapted so the cushion deflates at an appropriate rate to slow the driver/passenger.
There is not diagnostic system or warning lamps connected to the SIPS bag.
The SIPS bag is only installed in vehicles that are equipped with an SRS system and always fitted in both front seats.

SIPS bag, component overview





Sensor unit components
4. Sensor housing
5. Aluminium casing
6. Spring washer
7. Impact pin
8. Compression washer
9. Detonator
10, Transport lock

Cushion module components
11. Cushion
12. Gas generators
13. Combustion chamber
14. Installation bracket