BMW 3 series E30

Since 1983-1994 of release

Repair and car operation

14.47. A safety pillow: troubles or pleasures?

THE GENERAL DATA

On the statistican, cases of front (face-to-face) collision make more half of all collisions of cars. One of protection frames of the driver and the passenger at front blow – a pillow of safety which is intended for protection against contact to a steering wheel, the panel of devices, a windshield. For this purpose the pillow should be inflated for a time interval from the moment of blow of a car till the moment of contact of the driver with a steering wheel (it makes approximately 15–30 милисекунд). However it is necessary to notice that only in a combination to a seat belt "Airbag" provides extremely effective protection, reduces risk of reception of a serious trauma to a minimum.

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

Well, in general, the pillow and system elements are collected in one place – a steering wheel (it is independent system). What here enters? And: газогенератор and an inflatable bag – the pillow module.: the electronic gauge of collisions. In: a control lamp.

At ignition inclusion for 3–4 seconds the control lamp testifying to serviceability of system lights up. "Asterisk" – all O.K.Nu has gone out, and in all other cases the red spark on a wheel (below on the panel of devices) informs: with a pillow something not so, the highly skilled help is necessary. And it is important! Also remember that any works on repair, installation, service of elements of system of a pillow are authorised for making only specially prepared and обученому to the personnel HUNDRED. (And that can and shoot, moreover as!).

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

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

I consider as the debt to pinpoint that "adjust" each pillow of safety under concrete model of a car. For each family of cars develop own or pedantically adapt existing system, spend great variety of tests (including "kresh-tests").

Besides, safety pillows test for electromagnetic compatibility with a car network, on "false operation" etc. Results hide in electronics as original terminators – operation thresholds. After all in any way it is impossible to admit, that the pillow has worked that the driver зазевался and a car has got into a hole on road. And such happens – and then prepare to operation of a pillow of safety, moreover and for replacement of glasses if they have not been closed. And replacement of a pillow of safety costs недешево. For example, to replace a pillow for the driver will manage in 1600 US dollars, and even is more expensive, and all system with gauges, etc. is subject to replacement.! And that – to order. So this expensive pleasure. So, advantages of a pneumopillow:

1. It does not disturb at movement and is imperceptible (oh, these belts! Has removed, has clasped, has hung up, yes they still require adjustment).

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

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

But along with these advantages there are also minuses:

1. The big noise level at filling (because of it at test of the first pillows at verifiers eardrums burst).

2. An inefficiency of pillows at lateral collisions and опрокидываниях.

3. Working capacity of pillows after long use is insufficiently studied.

4. There are fears concerning false operation.

The safety wall is developed for elimination of some lacks of a pillow of safety. 1st part of a pillow limits vital space of the driver at front blow or overturning. The second element protects the driver at lateral blow from contact with elements of a body of a car. But it while is at invention level, while... Though there is already an attempt of completion of a car not one standard pillow, and three. One standard, is located, as usually, in a steering column. The second – at level of a breast in the form of a pillow-mattress for the swimming protecting the driver from lateral blow in the field of a trunk. And the third – limits vital space in the field of head moving. All these shifts are directed on lowering a traumatism, frequently and death rate. Also we will hope that this magnificent pillow it becomes fast not a subject of "an additional complete set", and the ordinary invisible fellow traveller of the motorist, saving to it a life.