When should the airbag deploy? Airbags (Airbag) - features, principle of operation and purpose How an airbag works

According to statistics, about 50 percent of all car accidents fall on a frontal collision. This indicates that the topic of airbags is extremely important. That is why today we will talk about this effective means of protecting the driver from injury.

Airbags are just one of the means to save life and health

How important are airbags?

For a long time, seat belts were the only form of protection. There was a lot of controversy around this, however, in the end, driving on the road with fastened seat belts became a mandatory condition in all countries. As practice has shown, this measure has saved the lives of thousands of unlucky drivers who could easily die in collisions.

As for airbags, they appeared relatively recently (at least in the form we are used to) and are soft supports that alleviate the consequences of an accident. For the first time, an inflatable pillow for aircraft was patented - it could be purchased back in the days of World War II. And in the eightieth year, the first pillow for cars was released.

Note! According to research, modern airbags reduce the risk of death in a frontal collision by about 30 percent.

As a rule, they are installed in the driver's seat and in the front passenger seat, but in recent years, car models equipped with six or even eight pillows that protect all passengers in the passenger compartment (products are additionally installed in the seats and side doors) have become increasingly common.

Airbags - how do they work?

So, the main function of these protective equipment is to prevent direct contact of the driver and passengers with the dashboard, steering wheel, windshield, etc. For maximum safety, the airbags inflate exactly at the moment when a collision has already occurred, but before the person touches the steering wheel. As a rule, this period of time ranges from 15-30 milliseconds. Yes, they didn’t forget about the seat belt - it also helps to minimize the consequences of an accident, but in combination with airbags it helps to avoid injuries altogether.

Note! Often the pillow is hidden in a large steering hub. In addition, a car equipped with the described protective equipment differs from a car without them in that the steering wheel shaft in it is longer, and the shape of the steering casing is somewhat modified.

From a structural point of view, the airbag consists of the following main elements:

• inflatable bag (a peculiar name for a gas generator);
• control lamp;
• an electrical sensor that is triggered in the event of an impact.

When the ignition is switched on, the warning lamp comes on after about three to four seconds. And if it goes out, it means that everything is in order with the security system and it is completely ready for operation. But if the indicator lights up red, then there are problems in the system and you should immediately contact a car service for professional help.

How the airbag works

The procedure for deploying the airbag itself is nothing complicated. In dynamics, it should look something like this.

Stage one . The vehicle collides with an obstacle.

Stage two . As a result, an electronic sensor is activated. The system is notified of the failure and takes action.

Stage three . The signal from the system reaches the detonator. It explodes, which provokes the destruction of the iron shell of the cylinder, which is filled with gas. At the same time, the gas itself, by the way, is under pressure there, reaching 250 MPa. As a rule, it is either ozone or argon.

Stage four . The pillow (and it is multi-layered and consists of nylon fabric) is filled with gas. Its thickness is usually 0.4 mm.

Stage five . Then the pillow increases and through special slots in the cover of the module breaks out.

Stage six . She opens up. Often this takes no more than 30 milliseconds after the sensor is activated.

Stage seven . The driver hits his head on the pillow and it absorbs the impact energy, after which, releasing the contents, it begins to fall off.

Note! All this happens extremely quickly. The airbag is capable of dissipating about 90 percent of all interaction energy, although the rest - that is, 10 percent - still falls on the driver.

Note also that each car model has its own settings for this protection tool.

Watch how the airbag works (video):

The main advantages of airbags

1. This is an effective means of protecting the head and chest of a person from serious injuries.
2. The pillow is more comfortable than the seat belt because it does not need to be fastened/unfastened periodically. Moreover, the pillow is also invisible to others.
3. Finally, all pillows do not need any special additional conditions at all.

Fly in the ointment: about the disadvantages of pillows

1. Possible false positive.
2. When the pillow is filled with gas, it makes a lot of noise.
3. The performance capability of a product used for a long time is poorly understood.
4. Finally, airbags are ineffective in a side impact or vehicle rollover.

However, it is worth adding that some shortcomings are absent in more modern car models.

What are airbags?

Immediately make a reservation that there are quite a lot of them, so we will get acquainted only with the most popular varieties.

1. Front cushions are the most common, and they are installed for both the driver and the front passenger.
2. Also have side airbags - so to speak, the next stage in the development of the system. They are designed to protect the pelvic region and chest during a side impact.
3. head pillows (they are also called "curtains") are required to protect the head from hitting solid elements in a side collision.
4. knee pads reduce the likelihood of knee injuries (and this is not uncommon with a frontal impact).
5. Airbag equipped seat belt. Protects the chest from injury.
6. Central cushions created relatively recently and designed to prevent a collision of two people sitting side by side in the event of a coup or side impact. Moreover, these products protect the neck from injury.

What to look out for: safety precautions

As you know, sometimes airbags not only benefit, but also harm. However, the latter is possible only with improper operation. What could this mean?

1. The distance between the passenger and the pillow must be at least 25 centimeters, otherwise, upon impact, the protective equipment itself may injure him.
2. If the child is transported in front in a special chair, then he should “look” in the direction of movement, and the chair itself should be pushed back as far as possible.
3. All passengers must be fastened. A fastened belt will slow down the speed of the body, as well as direct it to the right place - right on the pillow.
4. The pillow will not protect the child as much as an adult, so it should be transported from behind, and only in a specially equipped seat (it must be appropriate for the age of the baby).
5. Reversing a child seat in the front seat is not acceptable if the front airbags are active.

Outcome

When used correctly, airbags greatly increase the chances of occupants surviving and suffering less injury. Every year, thanks to this invention, the lives and health of thousands of people are saved, so try to monitor the health and stability of the entire security system of your car.

In this article, we will consider the definition, purpose and principle of operation of this passive safety element.
More than one million people are killed in car accidents worldwide every year. The Russian Federation is one of the leaders in the anti-rating of European countries in terms of the number of fatal road traffic accidents. The most important role in the outcome of a dangerous situation on the road is played by the presence of various active and passive safety systems in the car. In this regard, both car manufacturers and ordinary car lovers today are increasingly puzzled by the safety of the car. The most common element of passive safety is the airbag. For many years, it has been a reliable means of protecting a person and significantly reduces the risk of death (by almost a quarter in the event of a frontal collision), as evidenced by numerous tests at the test site. How the airbag works and its other nuances - more on that below.

More is better

Nowadays it is difficult to find someone who will be against this element of protection in a modern car. When buying a car, many people are guided by a number of criteria, and safety often occupies not the last place on this list, but for some it is the most important thing. Therefore, it is not surprising that the consumer tries to choose the car that has more "air bags". And this is the right approach.

Not a panacea

The history of "air bags" has more than one decade, and throughout the existence of the pillow, engineers have made this element more and more multifaceted in terms of human protection. But, you need to be aware that the pillow is not a 100% guarantee of protection against injury.
A fact that requires attention: since the advent of the "air bag" and even in our time, there are those who believe that the pillow can replace the seat belt. However, later it turned out that this is not true. The "air bag" is not able to provide a high degree of protection alone, but paired with a belt, it is quite possible to achieve satisfactory performance. For at the time of the accident, the belt fixes the body and the pillow takes the brunt, while the absence of a belt is fraught with arbitrary movement of the body around the cabin at the time of the disaster. As a result, the useful cushion coefficient is sharply reduced.
Moreover, at the time of the accident, in an unfastened state, a person risks serious injury moving by inertia towards the expanding airbag.
In addition, an important fact must be taken into account: the “air bag” has a one-time purpose, and if it is disclosed, only a new one can provide the proper level of protection.

Principle of operation

How does it all work? This mechanism includes a number of nodes:

It's all about seconds

All these elements are necessary for operational interaction with each other and instant opening of the airbag at the time of an accident.
The algorithm is as follows: in the event of a collision, at least one sensor responds to the impact. Further, the sensor by inertia sends the desired signal to the microprocessor. It is activated and then the opening command "explosion" follows the cartridge. An insignificant explosion is formed, which entails a nitrogen surge and a pillow, which is filled with gas from the inside, shoots into the cabin space.
At the moment of opening, the pillow envelops the person with its surface, thereby softening the blow. At the same time, the opening of the "air bag" will prevent the ejection of a person through the windshield.
The whole process takes place in a matter of fractions of a second, often not exceeding a quarter.

Advantages and disadvantages

After an accident, the airbag deflates on its own. Based on this, we can conclude that the presence of a pillow will not be an obstacle at the moment when you need to get out of the car.
The disadvantage is that the pillow is disposable. And if, after the first blow in an accident, the second-third-fourth follows, the "bag" no longer fulfills its functions.
What are "inflatable bags"
There are many types of airbags. One aims to protect the driver. The other is for passenger safety. The third one does serve to protect pedestrians - as a rule, such pillows are fixed outside. There are even "bags" for bikers that prevent ejection over the handlebars in the event of a head-on confrontation.
In general, as a rule, security "bags" are lateral, as well as frontal.

Front line

In our time, it is the "bags" of the frontal location that are most often used, which create a barrier between those who sit in front and the car's torpedo. These pillows are integrated into the steering wheel, as well as into the front panel in the glove box area, near the passenger seat.
It must be taken into account: the presence of a frontal “bag” for a passenger requires the latter to comply with a number of elementary rules. For example, a passenger should not hold large items in front of him (this also applies to a bag) and press his knees against the panel. Otherwise, it is fraught with serious bodily injury at the time of opening the "bag".

The situation on the flanks

At the moment, any self-respecting automaker is trying to integrate side “air bags” into their model (in the backs of the front seats, on the doors and pillars). These are lateral security measures. Such solutions have not yet been widely used, and often only wealthy buyers have access to such protection. As a rule, this is a premium car segment.
This mechanism is triggered by a significant push into the side of the body. Such pillows are called "curtains" in connection with their disclosure within the windows. This saves passengers' heads and necks.

Intelligent Security

Progress is moving forward, and thanks to it, more and more perfect pillows appear. For example, some modifications have such smart electronics that they have the ability to decide how much to open up. This makes it possible to choose a “configuration for yourself”. "Bloating" will occur taking into account the characteristics of the physique of a person, as well as the location of seat belts on them. So you can achieve a reduction in bodily damage. To do this, there is a special mechanism that works on the sensor, which allows such a scan of a person.

The airbag is not a panacea. No high technology can protect a person if he himself does not wish it.

Therefore, the belt must be fastened at all times and everywhere. The pillow is just part of the defense mechanism. When the "bags" work, you need to be prepared for the fact that they will swallow the main blow, but there will still be minor abrasions.

materials

There are many information resources on the global network that tell about how the "air bags" work. There are also related videos.
In general, all the necessary information can be obtained from crash tests. Specialists are working at the site who are studying such systems for preventing bruises. Therefore, the best way to find out how the "air bag" works is to go to a crash test site and watch a video.

Driving safety is one of the first issues that a future driver should take care of when buying a car. Among all safety elements, airbags occupy a key place. High-quality pillows can protect against impact even when seat belts are not fastened.

Almost all modern cars are produced with the expectation of the subsequent installation of airbags, so you should not worry in advance about “where to install them” and “is there a place for them in the car”. It is the principle of distinguishing airbags by location in the cabin that underlies the main classification of airbags.

Frontal

As the name implies, they are designed to extinguish the momentum in a head-on collision. The driver's airbag is located in the steering wheel, and the passenger airbag is hidden in the panel. The main purpose of frontal pillows is to prevent injury to the most vulnerable places on the body: the head and neck. The pillow absorbs about 90% of the entire impulse, and also significantly softens the contact of the face with the surface in front of it.

Side (curtains)

As a rule, curtains are located in the extreme cavities of the driver's and passenger's seats. Unlike frontal airbags, side airbags are designed to mitigate the effects of an impact on the body as a whole, and not just on the upper body. There are also driver and passenger airbags. Normally, there are two curtains for each (they are located at the edges from the head).

Head (cervical)

There are also two for each. They are a kind of lateral, but more specialized. Designed to protect the head from a side impact. They are located in the roof of the car, both from the side of the door and in the center.

knee

A fairly recent variety of pillows, the main purpose of which is to protect against injuries of the fragile knee joint. On the driver's side are under the steering wheel, on the passenger side in the glove box area. Worth two.

Central

Like the knee ones, they appeared quite recently and are functionally very similar to curtains (side airbags). They provide additional protection for the hands, especially in side collisions. Such airbags are located in the central part of the cabin. They cost a maximum of two for the entire car - one for the front and one for the rear (if possible) passengers.

In addition, all pillows can also be conditionally divided into passenger and driver. The fact is that the driver's seat, as a rule, is somewhat different from the passenger seat in the average distance between the body and the nearest hard surfaces at the time of the collision. The biggest difference is the distance from the driver's body to the steering wheel., which varies greatly with the distance between the passenger and the dashboard.

There are other small differences in distances as well. In this regard, when installing airbags, their size and full deployment speed must be selected taking into account their location and the design features of the car. Fortunately, pillows are already beginning to appear on sale, the work of which can be ideally adjusted based on many parameters, among which there are even such as the height and weight of the driver.

A new type of airbag designed for rear passengers is currently being developed. The impetus to start development is frequent injuries among rear passengers, whom seat belts do not always save from impact. The reason rear seat cushions have yet to be developed is because of the even greater variation in distance between the passenger and the vehicle's interior surfaces than in front seats. This implies that the principle of operation of the rear airbags, although it will be based on the same squib and gas emission, it is not known how many technical modifications they will have to undergo before their final implementation. However, given the current advances in the development of security systems, you can be sure that they will be on sale in the coming years.

Device

In the device of any airbag, three main elements can be distinguished:

• The airbag module, which includes the airbag itself and its accompanying locking and actuation mechanisms (spring, slip ring and squib).
• Shock (deformation) sensors.
• System operation control module.

The control module includes a system for recording data from collision sensors, a system for diagnosing the state of airbags (their health) and a driver warning system in case of a malfunction in the system (warning lamp).

Strain sensors are devices that are located in different parts of the car and will work if there are excessively sharp changes in the speed of the car.

The main elements of the airbag module are the airbag connector, the clock spring and the contact ring (for the airbag installed in the steering wheel), the squib, the gas generating element, the cover and the airbag itself. The airbag is made of thin nylon with a thickness of about half a millimeter, which has sufficient strength to brake the body of the driver (passenger) flying by inertia.

The igniter is a detonating device that, by its detonation, contributes to the release of gas from the gas generating element, which inflates the pillow in a fraction of a second.

The clock spring is an element specific to the steering airbag that facilitates uninterrupted power supply to the module and its communication with the control module. Pillow connector provides connection of the module to the control system, as well as notification of the presence of problems in the performance of the pillow in case of poor connection.

During maintenance work, the connector prevents accidental deployment of the airbag.

The airbag cover (also known as a plug) is a decorative element that hides the airbag from view until it deploys.

Operating principle

In general terms, the principle of operation of the airbag is as follows: after the impact of the car, the sensors that are in the car will work. Once they are triggered and send a signal to the airbag controller, the latter determines how many and which airbags to activate. Then, a signal is given and the squib located in the airbag is triggered, inflating the pillow.

Now in more detail. When a car gets into an accident, as a result of the impact, the car acquires uncharacteristic acceleration for it, and also gets damaged. A sudden change in speed as a result of an impact is a condition for deploying airbags. These changes are instantly recorded by the corresponding sensors. Sensors transmit information to the control module, from where the signal goes to specific airbag modules.

Upon receipt of a signal to operate, the squib in the airbag module detonates. The volume of gas released as a result inflates the airbag in a matter of fractions of a second.

How long does it take? As a rule, the response time is on the order of 15-25 milliseconds. Such a short period of time is due to the need to inflate the pillow before it makes contact with the body. Otherwise, the impact on the pillow will not only not be softening, but can cause serious injury, and even death. Such cases occurred in the early stages of the history of the development of airbags. Modern airbags are free from these shortcomings. In addition to instant opening, they also have such a structural feature as gas outlets. This means that the airbag begins to deflate almost immediately after deployment, thereby compensating for excessive pressure on the body of the victim, preventing him from suffocating (in the case of front airbags).

Outcome

Of course, whether or not to install airbags on your car is everyone's personal choice. However, based on many years of accident statistics, one should not refuse to install an airbag without a good reason. If you have any doubts about whether you need an airbag, then it is best to stock up on confidence by watching a video and reading the relevant literature.

The history of the creation of the airbag (air bag).

Prerequisites.

The first airbag was installed on a production car about 25 years ago. Then it was an optional addition, which was taken as an exclusive. Today it is impossible to imagine a car without this innovation, even if the path from improvement to universal recognition was very thorny.

As technology developed, cars became more and more, and they, in turn, added in their power and became faster. The number of accidents increased, more and more people who got into them died and were seriously injured. In the United States, as in the leading automobile power, the death statistics were the most ominous. Therefore, in 1967, they passed a legislative act that obliged all cars in the country to be equipped with an "automated passenger protection system" since 1969. But at that time, apart from conventional (non-inertial seat belts) seat belts, the designers could no longer offer anything.

It was then, in 1967, that they remembered the idea that was proposed in 1953 by the American John Hendrick and the German Walter Linderer. According to the patents he issued, the device was a "foldable deployable bag attached to the steering wheel, which was inflated in case of danger." Many developers have undertaken to implement this idea, but they have encountered many problems. In addition, in 1970, engineers came under serious pressure from the newly created Highway Safety Authority (NTHSA), which required all new cars to be equipped with airbags from 1973 onwards. The task, to put it mildly, was impossible.

Anticipating that the implementation of this directive would be delayed for a long time, a campaign was launched in the media and in the political arena against this security system. As a result, the deadlines for the introduction of technological innovation were first extended until 1976, and then completely canceled as a directive. Only in 1993, this directive was finally enshrined as mandatory.

Structural difficulties and their solutions.

Implementing the idea of ​​a "deployable" bag required incredible efforts. The components of a modern airbag: a squib, an inflatable bell, a set of sensors and an electronic control unit - all this had to be invented from scratch.

The required response time indicator - 30-50 milliseconds was achieved only with the pyrotechnic principle of filling the airbag. Therefore, he was immediately adopted. But the question remained open, how to fill the squib? When choosing a filler, it came to curiosities, the designers even tried to use rocket fuel. Often such experiments led to the destruction of the car. In addition, the cartridge must be compact, and the products of combustion should not pose a danger to humans.

The deployment of the airbag is accompanied by a sharp increase in pressure in the passenger compartment and a loud pop (of the order of 140 dB), which can damage the eardrums. To confirm safety, the designers resorted to the old method - they placed cages with fifteen canaries in the cabin. These birds, "fragile" to the acoustic effect, passed the experiment perfectly and even retained their singing abilities.

The dense fabric from which the main part of the pillow (the bell) was made was too thick, and besides, it passed part of the gas. Over time, designers came to the conclusion that the optimal material for this element is thin and durable nylon (about 0.5 mm thick) with a sealed coating.

A mechanism that was simply capable of deploying an airbag safely and quickly was not enough. It was necessary to force him to reveal himself in time and only at a critical moment. Spontaneous deployment of the airbag on the go is very dangerous for the driver. Also, a person should hit a pillow that has already opened, but has not yet begun to deflate. The use of an airbag that does not work at the right time brings only inconvenience and, in some cases, even injury (after all, the speed of the deploying airbag is about 300 km / h).

To construct such a smart system, the help of experienced people was required. The Bosch concern, with its vast experience in the field of electronics and electrics, was just right for this role. The control system, together with the sensors, had to transmit a signal to the squib in a few milliseconds, not responding to weak influences and maintaining its performance regardless of operating conditions.

To fulfill all these conditions, the company took more than ten years of work, more than two hundred crash tests on production cars and about 2,500 on mock-ups, spending over 7 million kilometers of test runs on this. An interesting fact is that about 600 experimental cars were tested with Mercedes employees at the wheel. Needless to say, this was a very risky undertaking.

By December 1980, 13 years after the start of work, the first mass-produced car equipped with an airbag was produced. Few people could afford this option, but it was clear that the future lay in airbags.

The effect of the introduction of the new security system was obvious. During the 80s, the number of deaths and serious injuries decreased by 5%, and in the 90s, when the use of an airbag became a mandatory requirement, it significantly decreased. Airbags, having shown their effectiveness in practice, have become an integral part of the configuration of most cars.

Airbag locations.

Systems of "inflatable" protection have long been placed not only frontally, but also from the side. After all, among the accidents, there are cases when passengers are endangered precisely from side impacts on the car. Airbags mounted not only in the steering wheel, but also in the side doors, the backs of the front seats, in the roof pillars and above the doors have found their distribution.

In open cars, the requirement for side airbags is special. Due to the lack of a hard top and racks, they had to be mounted in the upper part of the door and made more durable. Often it is proposed to equip the car with additional "airbags" to protect the feet and knees, as well as to prevent "diving" under the seat belts. Passengers sitting in the rear seats also receive separate pillows.

Safety above all!

In the fight for safety, inflatable bag technology has expanded beyond the interior of the car. The latest prototypes provide safety not only for passengers, but also for a downed pedestrian. Airbags deploy at the points of contact with the car (at the edge of the hood and in front of the bumper), protecting the head and legs of a downed person from injury.

The number of sensors and airbags in a car is growing every year, and they themselves are adding to their manufacturability. The latest sensors are able to distinguish between types of impacts by strength and character. There are even those who can recognize the situation when another car crashes into a stationary car, and this is given that airbags usually do not deploy at speeds of less than 20 km / h.

The speed of the airbags has become faster, now it takes no more than 20 milliseconds to fully deploy. Igniters have become safer and more environmentally friendly. Filters do not let through hazardous gases and solid particles. Pillows have become adaptive, i.e. internal pressure and degree of opening varies depending on the force of impact. Thanks to the sensors installed in the seats, "airbags" do not work if the seat belts are not fastened or there is simply no one in the seat. The first samples of airbags maintained the necessary pressure in the dome for about 2 seconds, now they do not go down to 10 seconds. Thanks to this, the passenger is protected from a second collision or a subsequent rollover of the car.

The new "airbags" take into account the peculiarities of human physiology. Previously, when triggered, the airbag could inflict damage on the face of the person being protected, now bifurcated passenger airbags have appeared. The main blow is taken by the shoulders and chest of a person, and the impact on the head is minimal.

There are variations of airbags that are designed for both drivers and other passengers. The driver's airbag is usually mounted on the steering wheel, passenger - on the instrument structure and on the seat backs.

Pillows located in front serve to protect the driver and passenger from injury by hard objects (interior, car body, etc.) and glass fragments in frontal collisions.

The airbags deploy on a direct impact. Depending on the direction of impact, only certain airbags are activated. Shock sensors transmit a signal to the control unit if the impact force exceeds a dangerous threshold. The control unit, having processed the data received from all sensors, determines the need and time for the operation of airbags and other components of the passive safety system.

Depending on the situation, only the seat belt pretensioners or combined with the airbags may be activated. The control unit provides an electrical signal to activate the gas generators of the respective airbags. The airbag ruptures and deflates only after touching a person.

Airbags should not be reused once deployed as they are a disposable vehicle component.

Additional conditions for the deployment of front airbags:

car fall;
Hitting a hard solid object;
Hard landing after a jump;

It is important to know that frontal airbags do not deploy in a rear impact, side impact or rollover.

The latest developments in the field of security.

Motorcycle airbag.

Honda unveiled the world's first motorcycle airbag system.

The air chamber itself is mounted in the center of the steering wheel. The airbag is deployed when all four "crash sensors" detect a severe frontal collision. An inflated buffer prevents the rider from flying forward.

The first bike to feature airbags was the "Gold Wing", Honda's largest and heaviest motorcycle. Prices for such a motorcycle start at 18 thousand dollars.

It is impossible to equip all motorcycle models with such airbags for technical reasons. Since the cushion absorbs the kinetic energy of the rider flying forward, the bike itself must be heavy enough not to roll over and throw the owner past the deployed camera.

In addition, sufficient space is needed to open the "Air bag", therefore, such a system cannot be installed on a sports motorcycle, the rider of which is pressed against the bike while riding.

"Smart" airbags.

Modern airbags are distinguished by their exceptional manufacturability. In 2006 model year sedans, the airbags are equipped with sensors that allow them to adjust the amount of deployment to prevent serious injury based on the passenger's posture and weight. Thus, the pillows are equipped with two degrees of deployment, limited and maximum, which are automatically selected depending on the weight of the passenger and the tension of the seat belt.

Undoubtedly, over many years of work, designers and engineers have developed a high-tech security system, but despite the great achievements in this area, it cannot be said that they are at the peak of development. A lot of things can be improved and modernized, a lot of unrealized ideas. Let's say it would be nice if the airbags did not work during the accident, but moments before it.

Whatever sky-high heights these "inflatable" technologies have reached, it should be remembered that the result of their work largely depends on whether a person was fastened with an ordinary seat belt.

Car manufacturers are trying to take care of their customers and equip cars not only with reliable seat belts, but also with airbags (also called airbags or Airbags). At the same time, in modern cars there can be from 2 to 7 of them. What are airbags in a car and how do they work? Let's try to figure it out.

What is "airbag"

The airbag device is quite simple. Conventionally, the product can be divided into three components: a bag, shock sensors and a gas generator (inflating system).

A bag

It is a thin, multilayer, nylon sheath (not more than 0.4 mm thick) capable of withstanding large short-term loads. The bag is located in a special tire, which is closed with a special lining made of fabric or plastic.

shock sensors

These components are usually located at the front of the machine. They are responsible for the timely operation of the car's airbag, that is, it is these sensors that activate it immediately after a collision with an object at a speed of more than 20 km / h. However, this also takes into account the impact force, so the airbag can work even in a stationary car if the collision was strong enough.

There are two types of sensors installed:

• Percussion (fix the impact that falls on the body).
• Passenger seat sensors (thanks to them, it is possible to exclude the operation of the system if no one else is in the car besides the driver).

In addition to sensors, accelerometers are also often additionally installed in the system (they help determine the position of the car).

gas generator

Initially, these elements were equipped with only one squib, which made it very difficult to regulate the gas supply to the pillow based on the dimensions and position of the person sitting in the car. However, modern "airbags" have 2 squibs. The first (main) releases 80% of the gas (the so-called soft landing), the second is connected only if the collision was too strong and the person needs a harder pillow.

All 3 components of the airbag must be in good condition, only in this case it can be guaranteed that the protective elements will work flawlessly.

How does the airbag work?

The principle of operation of airbags can be divided into several stages:

• Collision of a vehicle with another object.
• Automatic triggering of electronic sensors that trigger the next movement.
• The system receives a signal from the electronic control unit and a detonator (a charge of sodium acid tablets) is activated, as a result of which the gas (argon or ozone) heats up and bursts out under high pressure (up to 250 MPa). However, before that, it passes through a special metal filter and cools down.
• There is a sharp filling of the pillow, and it opens 30 milliseconds after the triggered sensors sent a signal.

• The driver or passenger of the car hits his head on the "airbag", which significantly dampens the energy of the impact received. Thanks to this, only 10% of the residual impact falls on a person.
• The pillow falls off.

Speaking about how airbags work, it is worth considering the design features of the car, since in some cars there are only 2 “airbags”, while in others emergency elements are installed in almost every plane.

Types of airbags

Today, cars can be equipped with several types of protective elements at once.

Frontal

"Airbags", located in the steering wheel (driver's) and at the top of the instrument panel (passenger), are considered the most common. They are installed even on the most budget cars. These pillows differ from each other in size, since the distance from the steering wheel to the driver is much less than from the person sitting next to the dashboard.

Elements work only in the event of a collision with the front of the car. However, a multi-stage driver airbag has already been developed, which is activated in collisions of various types and severity.

Important! The front passenger airbag has a deactivation button, which must be pressed if a child is transported in a special car seat on such seats.

When traveling in a car with frontal protective elements, it is necessary to check with the driver whether there is an airbag in the “torpedo”. If there is one, then you can’t carry bags, packages and other items in your hands or rest your knees on the place where the airbag is located.

Side

This type of airbag is usually found only in "advanced" car trim levels. These "airbags" are designed to protect the shoulders, chest, abdomen and pelvis in the event of a side collision. As a rule, these elements are placed inside the front seats, but there are also models for the rear seats, designed to protect people sitting in the back.

Healthy! If side airbags are installed in the car, then large or sharp objects cannot be stored in the door compartments.

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Also, these elements are often called head airbags, which by and large are also designed to protect passengers and the driver from side impacts, as well as from glass fragments. They are usually installed either for the front seats only or for both rows of seats. These elements are placed in the side parts of the roof of the car (above the windows) and sometimes in the side pillars.

knee

These protective elements are triggered in the event of a frontal impact of a car. Such pillows are installed mainly on cars of the middle price category (C-class). As a rule, protective elements of this type are located under the steering wheel and under the dashboard.

Important! If there is such an airbag, the driver must adjust his seat so that he is at a distance of less than 10 cm from the bottom of the panel.

Also today there are less common varieties of "airbags". These include rear side airbags and center airbags.

It is worth considering that when buying a used car, many may have a logical question, how to check the pillows. The fact is that the previous owner of the car could have already used the gas charge of the device, but did not refill the airbag (this can only be done at a car service).

Checking the airbags

Immediately after buying a used car, the new owner of the iron horse must make sure not only that his purchase is working, but also check the airbags. First of all, you should make sure that they are generally intended for this model of machine. This will be evidenced by the corresponding inscriptions SRS or Airbag on the steering wheel and dashboard. There should be no chips or scratches around these abbreviations, as this means that the protective accessory has already been used and not the fact that the previous owner took care of the expensive service of filling the airbags with gas. However, even if the product was reinstalled, there is no guarantee that the procedure was performed correctly.

Healthy! The shelf life of pillows is usually between 10 and 14 years (depending on the model, brand and year of manufacture of the machine). After this period, the cartridge is discharged and the product becomes unusable.

It is also worth paying attention to the glass (especially the windshield). If they have changed, then most likely the airbag has already been used.

It is worth paying attention to the date of manufacture of seat belts. The data must match on all seats. If these elements were replaced, then a possible cause is a strong blow, which also provoked the opening of the airbag.

In addition, there are several more ways to check the presence and performance of pillows:

• Turn on the ignition and wait for the inscription “airbag” to appear on the dashboard, which should disappear after a few seconds.
• If the car has a special connector for diagnosing the operation of systems (usually located under the steering wheel), then you need to start the engine, wait 30 seconds and close pins 4 and 13 with a regular paper clip. After that, the buttons on the dashboard should start blinking. If one of them displays a person with a pillow, and this button blinks more often than the others, then this indicates an error in the received code. If the light bulb does not show any signs of life at all, then this indicates that the car seller has turned off this module altogether.