Safety performance. On August 18, 1953, J.W. HETRICK obtained the patent for the first American airbag. However, it was not until 1984 that the automobile collision safety standard (FMVSS208) was re-recognized and implemented in the United States after being repealed many times. Since then, there have been continuous technological breakthroughs in seat belts, airbags, and safe body structures. As the CMVDR294 collision safety regulations begin to be implemented in China, domestic consumers have increasingly higher requirements for the passive safety performance of automobiles.
Technical composition: car safety
The advancement of technology allows people to experience the fun of driving more. The original seat belt was invented by the Swedes. The airbag appeared later. It is connected by a folded airbag (installed on the steering wheel), an inflator, an igniter, nitrogen solid particles and the corresponding wiring harness. Among them, the acceleration sensor to detect the collision intensity is integrated in the airbag. Inside the airbag controller.
Working process: When a collision occurs, the controller identifies and judges the intensity of the collision based on the acceleration signal
sent by the sensor. When the intensity of the collision reaches the design condition, the airbag is detonated. The sensor quickly triggers the ignition to detonate solid nitrogen particles, forming a rapidly expanding air bag to cushion the impact suffered by the front seat passengers and mainly protect their heads from injury. Of course, there is no need to be nervous. The sensor will automatically calculate the intensity of the collision and will not cause the airbag to deploy incorrectly due to improper driver operation, small obstacles or lighter collisions.
Opening principle: A minor collision will not open the airbag.
Generally speaking, the effective collision range for airbag deployment is only within a certain angle range of the front of the vehicle. Rear collisions, side collisions, and rollovers will not trigger the deployment of airbags. For example: the upgraded version of Santana 2000 will only deploy the airbag when it is severely damaged within 30 degrees on the left and right sides of the front of the car.
Necessary conditions for airbag deployment:
A. The vehicle speed is generally above 50 km/h, but the key factor is the acceleration at the time of collision (in the national certification test, the instant of collision The acceleration is about -40g;
B. Frontal driving;
C. Collision object: rigid wall or obstacle;
D. Opening time: in Within tens of milliseconds after the collision.
E. The rigidity of the collision object: The effect of a vehicle hitting a wall at 50 kilometers per hour is completely different from that of hitting a sand pile, so 50 kilometers per hour is only a relative speed. The airbag will automatically deploy only when the actual collision conditions are met.
It should be emphasized that fastening the seat belt is an important condition for the airbag to play a protective role.