In a variant, Chevrolet Niva cars can be equipped with a four-channel airbag system
Four-channel airbag - frontal airbag system for driver and front passenger with front seat belt pretensioner.
The four-channel airbag system includes:
- - driver airbag module (MNPBV);
- - airbag system control unit (BUSNPB);
- - connector with rotating device;
- - steering wheel with signal switch;
- - passenger airbag module (MNPBP);
- - right/left front seat belt pretensioner.
The driver's airbag module (MNPBV), (Fig. 1), consists of a gas generator 1, a body with an airbag 5 folded in it, a facing cover 2 and fasteners.
The gas generator produces gas inside the module to inflate the airbag.
The pyrotechnic substance in the gas generator is ignited by an igniter mounted in the gas generator body.
Inflatable airbag - a bag of synthetic material, mounted in the module housing, filled with gas under pressure when the module is triggered.
The airbag is specially folded and covered with a facing cover.
Facing cover - a part that closes the airbag and bursts when the airbag is filled with gas along the structural seam located on the back of the cover.
Block 1 (fig. 2) of the control of the airbag is fixed with three nuts on the bracket 2 on the floor tunnel and is located under the console of the instrument panel.
The BUSNPB includes an acceleration sensor and an electronic circuit for generating control signals supplied to the airbag modules and the seat belt pretensioners.
The control unit converts and processes the information coming from the acceleration sensor located in the unit itself and generates an electrical signal to the gas generator igniter of the airbag module(s) and the seat belt pretensioner.
The control unit performs diagnostics of the airbag, displaying the state of the system on the diagnostic indicator, and has software for storing fault codes and supporting the diagnostic data exchange channel via the "K" line according to ISO 9141.
The connector with a rotating device (Fig. 3) in the part of the airbag is designed for electrical connection of the driver's airbag module located on the steering wheel with the vehicle's electrical wiring.
The steering wheel (Fig. 4) structurally contains latches 1 for fastening the driver's airbag module.
Pretensioners (fig. 5) with a pyrotechnic element serve to increase the level Safety level for the driver and front passenger in the event of a frontal impact.
The pre-tensioners are aligned with the mounting brackets 1 and are attached to the seat slide through the spacer 5.
When the pre-tensioning device is activated, the belt lock 3 is pulled into the body of the pyrotechnic tube 7 by means of a steel cable 2 and pulled back, pulling the belt tape (not allowing the belt to loosen), and thus the belt fits the passenger's body tightly.
The purpose of this action is to reduce the load on the passenger's body by early participation in the braking process.
In the event of an accident, the pretensioners are activated using the BUSNPB.
Once triggered, the pretensioners are not reset and cannot be used again.
Instead of the triggered pretensioner, a new one is installed.
Triggering the pretensioner causes combustion of the combustible substance.
A solid fuel produces a gas in a fraction of a second, mainly consisting of nitrogen, carbon dioxide and water vapor.
Fuel consists of solid explosives, usually in the form of powder or granules.
When the pretensioner is at rest, these substances are in a sealed vessel (gas generator).
The details of the steering of a Chevrolet Niva with MNPBV are shown in Figure 6