BMW 3 Series E30

since 1983-1994 release

Repair and operation of the car

Statistically, cases of head-on (frontal) collision make more than a half of all collisions of cars. One of means of protection of the driver and the passenger at front blow – a safety cushion which is intended for protection against contact with a steering wheel, the dashboard, a windshield. For this purpose the pillow has to be inflated for a period from the moment of blow of a car until contact of the driver with a steering wheel (it makes about 15-30 milliseconds). However it should be noted what only in combination with a seat belt of "Airbag" provides extremely effective protection, reduces risk of receiving a severe injury to a minimum.

Usually the pillow is hidden in a massive nave of a steering wheel. In comparison with the car without safety cushion the wheel shaft, few other fastenings of a steering wheel is extended, facing casings are changed.

Well, generally, the pillow and elements of system are collected in one place – a steering wheel (it is autonomous system). What here enters? А: a gas generator and an inflatable bag – the pillow module. Б: electronic sensor of collisions. В: control lamp.

At inclusion of ignition for 3–4 seconds the control lamp testifying to serviceability of system lights up. "Asterisk" – all O.K went out. Well, and in all other cases the red spark on a wheel (below on the dashboard) reports: with a pillow something not so, highly skilled help is necessary. And it is important! Also you remember that any works on repair, installation, service of elements of system of a pillow it is authorized to only specially prepared and trained personnel to make HUNDRED. (And that can shoot, and in what a way!).

How this process in dynamics looks? Everything occurs in a flash! The sensor usually reacts either to deformation, or to delay, it gives a signal to a detonator which, blowing up, destroys a metal membrane in cylinders with the gas compressed to 200–250 MPas, usually the argon or ozone filling the pillow made of multilayered nylon (or polyamide) about 0,3-0,4 mm thick. That, being inflated, breaks off a module cover on special cuts and escapes outside. There pass only 15-30 milliseconds after collision, and the pillow already revealed and "waits" for the driver who only still began to be displaced forward. There is a contact! Extinguishing energy of blow, pillow produces gas through the special calibrated openings, deadly movement of the person is stopped, pillow executed the protective function and completely produces gas - "falls down".

And all this occurs in 0,5 seconds! Thus about of 90% of energy of blow dissipate, and remaining 10 return the driver's body in a starting position. Yes not so and just to fill and hide a pillow with a capacity of 40 l (and this majority of safety cushions) for a short instant!

I consider a duty to focus attention that each safety cushion is "adjusted" under concrete model of a car. Develop for each family of cars own or pedantically adapt the existing system, carry out great variety of tests (including "crash tests").

Besides, safety cushions are tested for electromagnetic compatibility with network of a car, for "false operation" etc. Results hide in electronics as peculiar limiters – operation thresholds. It is impossible to assume in any way that the pillow worked from the fact that the driver stood gaping and got a car into a hole on the road. And it happens – and then prepare to operation of a safety cushion moreover and for replacement of glasses if they were not closed. And replacement of a safety cushion costs expensive. For example, to replace a pillow for the driver will cost 1600 US dollars, and even is more expensive, and all system with sensors, etc. is subject to replacement! And that is to order. So this expensive pleasure. So, advantages of a pneumopillow:

1. It does not disturb at the movement and is imperceptible (oh, these belts! Removed, clasped, hung up and they still need adjustment).

2. Does not demand any additional conditions (everything is already ready in advance; well, it is not necessary to be fastened).

3. Reliably protects the head and a breast of the person from traumatizing.

But along with these advantages there are also minuses:

1. Big noise level when filling (because of it at test of the first pillows at testers eardrums burst).

2. Inefficiency of pillows at side crashes and oprokidyvaniye.

3. Operability of pillows after long use is insufficiently studied.

4. There are fears about false operation.

The safety wall is developed for elimination of some shortcomings of a safety cushion. 1st part of a pillow limits vital space of the driver at front blow or capsizing. The second element protects the driver at side blow from contact with car body elements. But it is at the level of the invention, so far so far... Though there is already an attempt of completion of a car not one standard pillow, but three. One standard, is located, as usual, in a steering column. The second – at the level of a breast in the form of a pillow mattress for the swimming protecting the driver from side blow in a trunk. And the third – limits vital space in the field of movement of the head. All these tricks are directed to reducing traumatism, often and mortality. Also we will hope that this magnificent pillow will become not a subject of "an additional complete set" soon, and the ordinary invisible fellow traveler of the motorist saving to it life.