Car Air Bags

Car Air Bags

An air bag is an inflatable cushion that prevents the occupants of a vehicle from serious injuries in the case of a collision. An air bag is a soft cushion to land against in case of an accident. For years safety issues while travelling were a serious matter of concern. To address this issue the seat belt was introduced. Statistics have shown that seat belts have managed to save thousands of lives which could have been lost due to collisions. The concept of the air bag was introduced after the Second World War. However the first commercial airbag was introduced in the 1980's.

Since 1998 it is a mandatory law in the US that all cars sold should have airbags for both the passenger and driver seats. To date statistics have shown that airbags reduce the risk of dying due to accidents by 30 percent.

Composition & Function Car of Air Bags

A typical air bag consist of an air bag module (containing an inflator or gas generator and an air bag), crash sensors, a diagnostic monitoring unit, a steering wheel connecting coil, and an indicator lamp. All these components are connected by a number of wires and are powered by the battery of the vehicle. The air bag system retains a certain amount of charge even after the ignition has been turned off or battery disconnected.

The crash sensors are designed to prevent the air bags from inflating when the car goes into a pot hole, over a bumper or accounts a minor collision. The sensors receive information from an accelerometer built into a microchip. The bag is made of thin nylon fabric which is folded into the steering wheel or dashboard or, more recently, the seat or door. The inflation system makes sodium azide react with potassium nitrate to produce nitrogen gas.

Car Air bags system

In the event of a frontal collision the crash sensors located in the front of the vehicle detect sudden deceleration and immediately send an electric signal activating an initiator. The initiator contains a thin wire that heats up and penetrates the propellant chamber. This causes the solid chemical sodium azide sealed inside the inflator to undergo a rapid chemical reaction. This reaction produces nitrogen gas that fills up the air bag. The nitrogen gas inflates the nylon bag in less than one twentieth of a second. It swells and spreads in front of the occupant. As the occupant comes in contact with the air bag the nitrogen gas is vented out through small openings behind the bag. This is how Car air bags system works.

Last Updated on 1/9/2012