With the growth of progress and material well-being, the statement "A car is not a luxury, but a means of transportation" is slowly but surely losing its relevance. Today, when buying a car, the future owner pays more and more attention to such a component as comfort. This characteristic includes many parameters that, at first glance, have nothing in common:

• The design and type of suspension, as well as the model of tires installed on the car;
• Soundproofing of the passenger compartment and engine compartment;
• Air conditioning system;
• Ergonomics of the seats and spaciousness of the cabin;
• The quality of the interior decoration material;
• Glass tinted or curtains;
• Availability of active and passive safety systems.

The latter is the basis for ensuring that both passengers and the driver feel protected, because that is where comfort begins.

Taking into account all these parameters when buying a new car means opting for elite models, the cost of which may be too heavy a burden for the budget. The search for the best option that would correspond not only to the desire, but also to the possibilities, can be a long and tedious quest that can pretty much fray the nerves of a future car owner. We decided to take an active part in the search and present to your attention an overview of the most comfortable cars that you can buy in car dealerships in Russia. For greater convenience, the selection of models for the rating was made in three fundamentally different car categories.

The most comfortable crossovers

This type of car assumes a large and spacious interior, high seating position and large wheel diameter. All of this is part of a more comfortable travel environment. The most comfortable crossover models will be presented in this rating group.

4 Renault KAPTUR

Best price
Country: France (produced in Russia)
Average price: 884,000 rubles.
Rating (2019): 4.4

Four-wheel drive French SUV entered the top of our rating because this model completely changes the way we think about Renault cars. A bright, slightly futuristic design, with the possibility of individualizing the appearance of a car using Atelier Renault elements, immediately attracts the attention of others. The comfortable and elegant interior has excellent sound insulation, and the three-contour door seals almost completely absorb sound waves from the outside as soon as you close the door.

Ergonomic seats create a pleasant atmosphere. Using a car for long trips will never be boring - the standard interior can be changed in accordance with the owner's preferences - just choose one of the ready-made design solutions. The presence of cruise control, climate control, active safety services with elements of intelligent driver support - this is also Renault KAPTUR.

3 KIA Sorento Prime

Spacious salon. Anatomical chairs with heating and ventilation
Country: South Korea
Average price: 2,495,000 rubles.
Rating (2019): 4.6

As a result of the technical updates of the model implemented this year, the third generation Kia Sorento received, among other things, a modernized and more spacious interior. The interior of the vehicle is highlighted by energetic interior trims made from quality materials. Anatomical seats with built-in heating and ventilation are literally made for long journeys. Even rear passengers can adjust their seat backrest tilt.

A premium multimedia system with a subwoofer, a wireless console for charging your phone - everything is designed exclusively for comfortable movement in space. Elements of active and passive protection, highly appreciated by Euro NCAP specialists, make driving a car as convenient and safe as possible.

2 Porsche Macan

The most comfortable salon
Country: Germany
Average price: 3,512,000 rubles.
Rating (2019): 4.9

The first thing that catches your eye when you open the doors of this car is the seats. They provide the most comfortable fit for passengers and the driver, adjusting to their preferences in 8 positions by simply pressing certain buttons. Adjusting the lumbar support for long journeys is an indispensable feature for maximum body comfort. In the basic version, all seats are heated, and a heated steering wheel is available as an option. Also, the standard version of the crossover is equipped with a three-zone climate system, which allows you to create an individual microclimate for both front and rear passengers.

By choosing a car with air suspension, the new owner will receive an SUV that completely isolates the driver and his companions from the surrounding reality. The car will simply "float" over the road, all the irregularities of which will not be able to disturb you in any way. Interior soundproofing with the use of modern materials will allow you to talk without raising your voice, even at high speed. As an option, you can install multi-layer tinted thermal glass, which will increase the already high level of comfort. There is a more conservative but effective alternative - mechanical shutters.

1 Audi Q5

Most comfortable suspension. Popular model in the domestic market
Country: Germany
Average price: 3,325,000 rubles.
Rating (2019): 4.9

Germans are very attentive to details, so their cars are the most comfortable and occupy a special niche in the market. Crossover Audi Q5, which was in the first position of our top-ranking, will amaze you with the smallest thoughtfulness of details and high-quality interior trim. Ergonomic seats and a customizable control system maximize ride comfort. In addition, Audi is considered the most "advanced" car and boasts many high-tech systems on board that make the trip not only comfortable, but also safe.

One of these systems is Audi Drive Select, which adapts the operation of vehicle components in accordance with the owner's priorities. A simple choice of mode - and the car becomes an off-road vehicle with high ground clearance or turns into a sports car with low ground clearance and a stiff suspension. In the Comfort position, the standard engine and transmission dynamics are activated and the air suspension is softened, which immediately affects the ride comfort. This option is especially relevant for long trips.

The most comfortable sedans

As a rule, these are premium cars, which are distinguished not only by the maximum comfort, but also by a high level of safety, as well as by the presence of integrated modern and high-tech systems that make everyday operation pleasant and not burdensome. The models presented below are the best and most comfortable cars that are sold in Russia today.

4 Nissan Sentra

The most attractive price. Spacious salon
Country: Japan (going to Russia)
Average price: 916,000 rubles.
Rating (2019): 4.2

Already at an external examination of the car, one gets the impression of the spaciousness of its interior - the length of the car is just over 4.6 meters. The strict and laconic elegance of the exterior of the car accompanies the passenger inside as well - aluminum inserts into the interior of the cabin give it a more expensive, respectable look. Convenient control of on-board systems, the availability of services (depending on the selected configuration), providing a more comfortable and safe movement.

For long journeys, seating comfort is of particular importance. The Nissan Sentra has a rather high seating position, almost like in crossovers - there is no feeling that you are "falling through". Lateral support, comfortable adjustment and ample rear legroom make any journey as comfortable as possible.

3 GENESIS G70

Innovative driver support systems. Luxury salon
Country: South Korea
Average price: 1,999,000 rubles.
Rating (2019): 4.4

This unusual, luxury car is the first representative of the premium segment of the South Korean Hyundai Motor Company. The elegant and modern design of the model anticipates the luxury interior comfort and innovative solutions implemented in the GENESIS G70. At your service is a projection of instrument readings on the windshield, an intelligent all-round view function, passive and active safety systems, a luxurious acoustic system consisting of 15 surround speakers, and many other modern high-end features.

The interior is characterized by luxury and high quality materials used for finishing. The most comfortable and "smart" driver's seat has deep lateral support and electronic adjustment in 8 positions (only the lumbar support has 4 adjustment points). The ergonomic rear seats provide a comfortable seating position, which is key for long journeys.

2 Lexus LS

Image model. High level of comfort
Country: Japan
Average price: 5,540,000 rubles.
Rating (2019): 4.8

The fifth generation of the most sought-after LS model, with a bright and dynamic design, is an integral attribute of speed and success. Only by sitting down on the magnificent, enveloping seats, you can fully experience all the luxury and comfort of this car's interior. In addition to ventilation systems and dual-zone heating, rear passengers have access to 7 types of acupressure, which relieve fatigue and relax, which is very important for long trips.

High quality speaker system, comparable in sound to a home theater, huge legroom for rear passengers (just over a meter) and adaptive suspension will allow you to completely withdraw from the outside world as soon as the door of this luxury car is closed. A three-year manufacturer's warranty is a confirmation of high quality and reliability, which is an integral part of comfort.

1 Mercedes S 350 d 4MATIC

Popular premium sedan. Comfortable suspension
Country: Germany
Average price: 6,720,000 rubles.
Rating (2019): 4.8

German "Mercedes" at all times of its existence has symbolized success, prosperity and a subtle sense of style of its owner. This is a good reason for him to enter the top of the best models in our ranking. Confident road behavior is ensured by the four-wheel drive and auxiliary control systems. Inside, the owner will find an exquisite interior, finished with high quality materials, excellent noise insulation, ergonomic controls, a range of state-of-the-art intelligent driver support services and comfortable seats. Thanks to these components, the driver (all the more so) not so much gets tired of traveling, but rests and relaxes, using the time behind the wheel to recuperate.

The special Curve suspension mode, which dampens inertial forces when cornering, makes the journey surprisingly comfortable. The futuristic soft neon illumination, which emphasizes the interior lines of the interior trim, adds pleasant emotions to passengers. A modern and very convenient projection screen displays not only the necessary information about the car's operation directly on the windshield, but also a navigation map (depending on the equipment type). Its peculiarity lies in the fact that the driver sees the information not on the windshield - the picture "hovers" illusoryly above the hood of this luxurious car.

The most comfortable Chinese cars

The constantly growing quality of Chinese models has become a good reason and reason for the most comfortable cars from the Middle Kingdom to be included in the top of our rating.

2 LIFAN X70

The best soundproofing of the cabin. Great popularity in Russia
Country: China
Average price: 799,000 rubles.
Rating (2019): 4.3

When designing this crossover, Chinese specialists provided 14 special niches in the body structure for installing additional noise insulation. In total, there are 28 noise-absorbing zones that guarantee the best acoustic protection for passengers and the driver. Contoured to the body, the anatomical seats provide maximum comfort for long journeys.

The driver will feel the support of the ESP complex, Hill Start Assist (stabilization system when starting on slopes) and many other systems that ensure the convenience of car operation. It is also worth noting the strict design style of the interior decoration - laconic, with smooth transition lines, it is designed to enhance the harmony and comfort of this car.

1 GEELY EMGRAND GT

Most luxurious. Comfortable seats for rear passengers with adjustment
Country: China
Average price: 1,209,000 rubles.
Rating (2019): 4.4

The secret of this car is that it is based on the proven and reliable Volvo S 80 platform (the Chinese now own this brand as well). Large and comfortable, the EMGRAND GT is equipped with the latest technology and is a serious competitor to more expensive and famous brands, the cost of which is significantly higher.

When finishing the spacious interior, a high-quality polymer was used, so there is no smell of phenolic compounds traditional for many cars from China. A two-zone climate system, electrically adjustable comfort seats (including the rear ones), a premium multimedia complex, an intelligent driver support system and many other features indicate that we are facing an expensive and prestigious high-class car.

A fishing rod or a long key is a hijacking method when intruders use a wave system designed for intelligence agencies. Retransmission of the key signal allows you to open the car, even if the owner is at a considerable distance. Ways to combat this type of theft.

During operation, scratches from wipers, scrapers and other fine abrasive appear on the car windows. Scratches and scuffs can significantly reduce the driver's visibility while driving, especially in the evening. In order not to change the glass, you can try to polish yourself.

Soundproofing car doors can significantly reduce the level of extraneous sounds in the cabin. The installation procedure for Shumka is not so complicated, so you can do it correctly even with your own hands. What materials are used for noise insulation, what are the positive and negative sides of the installation of noise for doors.

50% of car owners produce independent noise insulation of a car, while the other half orders this service from specialized workshops. Is it really so difficult to make a Shumka in a car with your own hands, what materials should be used in this case. How much material is needed and what types are better to use.

The rating of the most stolen cars in Russia is useful to study for all car owners, as well as for those who are just going to purchase a vehicle. The article contains statistics of car thefts since 2014. Fresh data for 2018, by the number of thefts in general and by specific gravity.

Double glazing of the car will help to avoid constant fines for the installed tinting. Having spent a certain amount of money once, you can forget about the problem forever. But it is advisable to approach responsibly to the choice of the contractor in order to avoid problems with double glazing in the future.

Since the vehicle is a source of increased danger, there is a list of malfunctions, in the event of which the driver is not allowed to use the vehicle at all. There is also a list of malfunctions with which the car can independently continue to move to the point of eliminating the breakdown.

Did you smell gas in your car? It is necessary to calculate the location of the leak, since you should not joke with gasoline. There can be several reasons for the appearance of the smell. First you need to figure out exactly what moment it appears, and then start the search. Perhaps it starts to smell when the engine is started, and then the smell disappears. We are trying to figure out what causes the smell of gasoline in the car.

Due to the fact that once a law was passed on the permissible level of tinting of car windows, drivers had such a problem as removing the tinting. You can make it in several ways - on your own, or by contacting the workshop. Removing the tint on your own is not so difficult, just know how to do it correctly.

Many have heard such an expression as an engine preheater. From the name it becomes clear its main function - to facilitate the winter start of the car. There are many different heaters from different manufacturers. By the type of implementation, they can be divided into two: autonomous and electric. You can learn about each of them from this article.

One of the necessary and important improvements to the car, without a doubt, is such a device as an autonomous interior heater. Thanks to this device, the required temperature can be maintained in the passenger compartment, without the need to start the engine. Such a unit is in the greatest demand among truck drivers, since it allows you to rest on the road under much more comfortable conditions.

A device such as an anti-sleep device allows the driver to avoid an emergency if he is tired and starts to fall asleep while driving. The sharp, shrill signal that the device emits, as soon as the head bends forward, will wake anyone up. Although by and large, it's best not to tempt fate and not rely on the device, but just stop and rest.

Tinting, whatever it is, reduces visibility and increases the likelihood of an emergency. Therefore, permissible norms of light transmission have been introduced, and a fine is imposed on drivers who violate these requirements. One of the options to avoid punishment is electric tinting. Read what it is and how it works in this publication.

One of the additional options designed to improve the comfort of the driver and passengers is the heated seats. This option is purely seasonal, but highly demanded. In luxury trim levels, seat heating is present by default, while others can install it on their own, with their own hands.

The rain sensor is optional and is designed to make the driver's life easier and more comfortable. There is no need to turn on and off the wipers on your own, the sensor turns them on independently, as soon as water enters its area of \u200b\u200baction on the windshield.

The safety of the driver and passengers of the car is a very important issue, and when it comes to children, there can be no compromises at all. For the greatest safety of children, the driver is obliged to use special child seats, which are fastened using the existing belts, or the isofix system, if available. What it is and in which machines it is available, read the article.

Many motorists, entering a turn at a decent speed, felt that a little bit more and the car would roll over. This is due to the impact on the car of centrifugal and other forces. In the fight against the possibility of car rollover, manufacturers equip them with various anti-rollover systems.

Transporting a bike by car is often difficult, especially when the car is not very large. What can we say about how to transport several bicycles at once. To do this, there are various attachments to the car's towbar, both factory-made (flexfix from opel) and many other solutions.

This article will focus on a special type of window tinting provided by the car manufacturer skoda. It is called sunset and can be applied directly at the factory. Whether such an option is needed, is it worth overpaying your hard-earned money for it and what is the use of it - let's try to figure it out.

Heat-insulating glazing, its other name - athermal, protects the car interior from overheating. This is achieved by using various additives in the manufacture of glass. Athermal glass is used by car manufacturers skoda and a number of others. Lately, toning with athermal films is gaining popularity.

Owners of Skoda cars are probably familiar with such a concept as the varioflex system. This is a very convenient implementation of the interior space of the passenger compartment, thanks to which the rear row seats can be folded in various variations, and, if necessary, completely removed. The varioflex system makes it possible to turn a passenger car into an almost complete truck.

It is difficult to imagine a modern car without such an option as air conditioning. A great many of them have been invented, and each is good in its own way. In this article, we will talk about the principle of operation of all such systems, and about a semi-automatic air conditioner called climatic.

To maximize the comfort of the driver and passengers, there are many different systems. One of these is the seat ventilation system. On expensive cars, in the maximum configuration, this option is found more and more often. But this does not mean that a person with an average income cannot afford seat ventilation. The option of its self-installation is possible.

Cars equipped with keyless entry systems greatly simplify the driver's life. There is no need to arm or disarm the car - the smart key system perfectly copes with all this. It is enough that the electronic key is in your pocket, and then the driver will be identified as the rightful owner of the vehicle.

The power window is the dream of any owner of a domestic vehicle. If now modern VAZ models are equipped with this option already from the factory, then on the classics, for example the same 2107, you will have to install the power window yourself. The article contains information on all possible types of power windows and their design.

What is an on-board computer in a car, for what purposes it is installed and why is it so popular among car owners. The answer is simple - this device allows you to control many parameters of the car, notify the owner about malfunctions, and generally make life easier for the owner of the vehicle.

What is a head-up display for and to what extent it is able to facilitate driving, as well as to maximize the safety of all road users. Modern electronic means, one of which is a display capable of projecting instrument readings onto the windshield, do an excellent job of increasing safety and comfort.

Surely many of us, at least once, had to get into such heavy rain that even the windshield wipers could not cope with the streams of water pouring from the sky. And what could be worse than fine drizzle, which makes the wipers work continuously, but the view still leaves much to be desired. Modern technologies make it possible to process car windows with an anti-rain agent, from which the water simply rolls off the glass.

The system of exchange rate stability, or dynamic stabilization of the car, is necessary in order to prevent an uncontrollable skid at the time of sharp braking, or loss of traction with one of the wheels. Based on the readings of many sensors, the system ensures that the driver does not get into an emergency due to road conditions or his inexperience.

Noise isolation excites the minds of many car owners, which is not surprising. After all, who does not want to drive a car without hearing the noise of the wheels, enjoy the silence, or say the music in the cabin, which is not muffled by the rustle of gravel under the wheels and the roar of passing cars. Yesterday the noise insulation procedure was long and expensive, but today, thanks to the appearance of liquid rubber, it is available to everyone.

It is difficult to overestimate the importance of such a system as assisted ascent and descent. It is especially needed, and even necessary for novice drivers who experience problems exactly when they need to move up the hill. Having many names, depending on the manufacturer, the principle of operation of this system remains unchanged.

In the struggle for road safety, mankind is more and more improving the inside of the car in order to achieve comfort and safety. Long travel time invariably affects the driver's condition, and sometimes driver fatigue leads to fatal consequences.

What is voice control of a car is not difficult to guess from the name of this option. The article will tell you exactly how you can implement the work of such a system, it also contains information about how the voice control system has evolved over time, and how the very first one differs from the latest developments in this area.

What a miracle is an active head restraint and is there any benefit from it for the driver. Let's try to figure it out. Numerous tests have proven that the active head restraint significantly reduces the risk of injury to the driver's cervical vertebrae in a rear impact. So far, this security system is not at all common, but we think over time everything will change, and the equipment of the car with active head restraints will become the norm.

The car's surround view system is another step towards road safety. This system allows you to monitor the traffic situation around the car in real time. This is achieved due to the video cameras and proximity sensors installed in a circle. Each manufacturer calls their systems differently, but they have the same basic principle of operation.

Everybody, at least most of car owners, represent what an expeditionary trunk is. How important and necessary to have this type of trunk for those who travel by car is a moot point. The article describes its main advantages, and also contains information on how you can independently make a trunk from available tools.

There are many road signs, and the driver has only two eyes, so it can be difficult to keep track of everyone. To facilitate monitoring the traffic situation, a device such as a traffic sign recognition system has been invented. She will warn the driver that it is necessary to observe the speed limit on this section of the road, or that overtaking is prohibited here. The system is very useful, but as practice shows, it does not always work as it should.

A person has always tried to automate certain processes as much as possible, and driving is no exception. This article will focus on a system such as park assist. The automatic parking system is capable of independently parking a car, without any human intervention. Regardless of whether the driver is in the car or not, the vehicle will find an empty seat and park the car.

Many sooner or later face a problem when the rear window heating stops working fully. This happens most often due to the breakage of the filaments, which provide this very heating. Let's look at the simplest ways to restore glass heating, which any car enthusiast with straight arms can do.

We have already found out what an immobilizer is and for what purposes it is needed in a car. In this article, let's discuss when and how a device such as an immobilizer crawler is required. It is clear that this anti-theft protection system can turn against you from the loss of a key, program failure or hardware breakdown. This is where the knowledge of how you can turn off the immobilizer comes in handy.

An immobilizer is an anti-theft device for a car, which works on the principle of blocking certain capabilities of a car, individual components or assemblies, which in turn leads to immobilization of the vehicle. And since hijackers rarely use tow trucks and other loading equipment when hijacking, the chances that the owner will have a car equipped with an immobilizer is quite high.

What is parktronic and is there a need to install it. Nowadays, quite a few types of parking sensors have already been invented, with and without cameras, with monitors built into the rear-view mirrors and without them, but the essence of the device remains unchanged - it is designed to make life easier for the driver, especially for a beginner. This is a kind of third eye. How it works and how to install it, read this article.

A central locking in a car is an irreplaceable thing, and it is found, in our time, on the vast majority of cars. What role does the central lock play, on what principle its work is organized, you can read in this article.

Do you buckle up while driving? More and more people in our time, realizing that courage can go sideways, began to take care of themselves first of all and wear a seat belt. And this is very correct. How the procession of seat belts began, what were the first of them, and what the evolution of safety has led to today - about this and another in this article.

Everyone has it driver there is a special opinion about the comfort of the car. For some, comfort is a unique hydraulic suspension, for another, air conditioning, for others, powerful audio and video systems are pleased. Another innovation car tuning - this is ... For lovers of the unusual tuning you can see recommendations on how to do it yourself on the AvtoNovator website lED backlight, which gives not only aesthetic pleasure, but also has practical value.

Also, someone, creating coziness in the cabin, covers it with heat-insulating materials so that in winter the summer temperature is always kept inside. Many drivers appreciate vehicle comfort for noise insulation and vibration car... Loud music lovers are always annoyed when noise engine or road noise drowns out music sounds.

But, surprisingly and not paradoxically, it is a comfortable car that becomes potentially dangerous. Car manufacturers, in their desires to make a beautiful toy out of a car, with a mass of additional accessories, thereby render a disservice to car owners. Statistics and expert data confirm this idea and warn of an increase in the number of accidents in the row of comfortable cars. Swedish researchers, analyzing this problem, came to the conclusion that drivers will have great difficulty in controlling the machine. According to scientists, cars equipped with a noise insulation system are in demand among young people drivers with little driving experience. The boys in this case belonged to the road noiseas a distraction that prevented them from listening to music in the cabin car... However, the opinion of professional drivers regarding noise on the road is completely different. They believe that isolated from noise It is difficult for a car to have an idea of \u200b\u200bwhat is happening around, and it is impossible to fully assess the situation on the road. Professionals believe that all sounds coming from outside to the passenger compartment signal a danger and are therefore useful while driving. By the sounding sounds, it is possible to determine the quality of the engine operation, on which road, with what surface it drives carwhich car is approaching to overtake.

Therefore, Swedish scientists issued an appeal to automakers not to create for drivers vacuum conditions. Noise plays, as it turned out, not only a negative role. Road noise reminds driverthat he is driving on the road to carinstead of lying on the couch at home and listening to music. By the way, scientists from Sweden were supported by people from public organizations of the visually impaired and the blind, for whom cars with a weak engine sound are dangerous.

Of course, as they say, you can't forbid living beautifully. It is always pleasant and easy to ride with comfort, when cheerful music is playing, outside the window is frosty, and in the cabin there is a tropical climate. And I don’t think at all about what is happening there on the road, and what awaits you around the next turn ...

COMFORTABLE

The comfort of the car determines the time during which the driver is able to drive the car without fatigue. The increase in comfort is facilitated by the use of automatic transmission, speed controllers (cruise control), etc. Currently, cars are produced with adaptive cruise control. It not only automatically maintains the speed at a given level

not, but also, if necessary, reduces it to a complete stop of the car.

3 Passive vehicle safety

BODY

It provides acceptable loads on the human body from a sharp deceleration in an accident and preserves the space of the passenger compartment after body deformation.

In a severe accident, there is a danger that the engine and other components may enter the driver's cab. Therefore, the cabin is surrounded by a special "safety cage", which is an absolute protection in such cases. The same ribs and stiffening bars can be found in the doors of the car (in case of side collisions). This also includes the areas of energy extinguishing.

In a severe accident, a sudden and sudden deceleration occurs until the vehicle comes to a complete stop. This process causes huge overloads on the bodies of passengers, which can be fatal. It follows from this that it is necessary to find a way to "slow down" the deceleration in order to reduce the load on the human body. One way to accomplish this is to design collision dampening areas in the front and rear of the body. The destruction of the car will be more severe, but the passengers will remain intact (and this is in comparison with the old "thick-skinned" cars, when the car got off with a "slight fright", but the passengers were seriously injured). AAAAAAAAAAAAAAAAAAAAAAAAAAA

The body structure provides that in a collision, the body parts are deformed as if separately. In addition to this, highly stressed metal sheets are used in the construction. This makes the car more rigid, and on the other hand allows it to be less heavy.

SEAT BELTS

At first, cars were equipped with two-point belts that “held” the riders by the stomach or chest. Less than half a century later, engineers realized that the multi-point design is much better, because in an accident it allows you to distribute the belt pressure on the body surface more evenly and significantly reduce the risk of injury to the spine and internal organs. In motorsport, for example, four-, five- and even six-point seat belts are used - they keep a person in the seat "tightly". But in "civilian" because of their simplicity and convenience, three-point have taken root.

In order for the belt to function properly, it must fit snugly to the body. Previously, belts had to be adjusted and adjusted to fit. With the advent of inertial belts, the need for "manual adjustment" has disappeared - in a normal state, the coil spins freely, and the belt can grab a passenger of any size, it does not hold down the action, and every time the passenger wants to change the position of the body, the strap always fits snugly to the body. But at that moment, when "force majeure" comes, the inertial coil will immediately fix the belt. In addition, on modern machines, squibs are used in belts. Small charges of explosives detonate, the belt is tugged, and it presses the passenger against the back of the seat, preventing him from hitting.

Seat belts are one of the most effective means of protection in an accident.

Therefore, passenger cars must be equipped with seat belts if anchorage points are provided for this. The protective properties of belts largely depend on their technical condition. Belts malfunctions, in which the operation of the car is not allowed, include tears and abrasions of the fabric tape of the straps visible to the naked eye, unreliable fixation of the tongue of the strap in the lock or the absence of automatic ejection of the tongue when the lock is unlocked. For inertial-type seat belts, the strap should be freely drawn into the reel and blocked when the car moves sharply at a speed of 15 - 20 km / h. Belts that have experienced critical loads during an accident in which the car body has received serious damage are subject to replacement.

AIR BAGS

One of the most common and effective safety systems in modern cars (after seat belts) are airbags. They began to be widely used already in the late 70s, but only a decade later they really took their rightful place in the safety systems of cars of most manufacturers.

They are placed not only in front of the driver, but also in front of the front passenger, as well as on the sides (in doors, body pillars, etc.). Some car models have their forced shutdown due to the fact that people with heart problems and children may not withstand their false alarms.

Today, airbags are common not only on expensive cars, but also on small (and relatively inexpensive) cars. Why are airbags needed? And what are they?

Airbags have been developed for both drivers and front-seat passengers. For the driver, the airbag is usually installed on the steering wheel, for the passenger - on the dashboard (depending on the design).

The front airbags deploy when an alarm is received from the control unit. Depending on the design, the degree of gas filling of the pillow can vary. The purpose of the front airbags is to protect the driver and passenger from injury by solid objects (engine body, etc.) and glass fragments in frontal collisions.

Side airbags are designed to reduce damage to people in the vehicle in a side impact. They are installed on the doors or in the seat backs. In a side impact collision, external sensors send signals to the central airbag control unit. This makes it possible to deploy some or all of the side airbags.

Here is a diagram of how the airbag system works:

Studies of the influence of airbags on the probability of driver death in frontal collisions have shown that this is reduced by 20-25%.

In the event that the airbags have deployed or have been damaged in any way, they cannot be repaired. The entire airbag system must be replaced.

The driver's airbag has a volume of 60 to 80 liters, and the front passenger's volume is up to 130 liters. It is easy to imagine that when the system is triggered, the volume of the cabin decreases by 200-250 liters within 0.04 seconds (see figure), which puts a considerable load on the eardrums. In addition, an airbag flying out at a speed of more than 300 km / h is fraught with a considerable danger to people if they are not wearing a seat belt and nothing slows down the inertial movement of the body towards the airbag.

The study of the working conditions of drivers indicates the significant importance of the parameters of the internal environment in the car. These parameters are only more or less likely to comply with the established standards, which makes it possible to extend the concept of reliability to a system that provides living conditions for people in a car. Operational observations are indirect evidence of its insufficient reliability in some cases. According to the results of a survey of a large number of professional drivers about the influence of internal environmental factors, the temperature regime in the cab (hot in summer, cold in winter) was negatively assessed - 49% of drivers; the presence of toxic substances (air pollution with exhaust gases) - 60%; the influence of vibrations - 45%, noise -

56% of the surveyed drivers.

1.13.1. Climatic comfort

Abnormal climatic conditions in the car cab have a harmful effect on the health of the driver and are one of the reasons contributing to the occurrence of an accident. Under the influence of high or low temperatures in the cab, the driver's attention is dulled, visual acuity decreases, reaction time increases, fatigue quickly sets in, errors and miscalculations appear that can lead to an accident.

One of the requirements of occupational safety and health is the exclusion of the possibility of penetration into the driver's cab of workers

gases that contain a number of toxic components, including carbon monoxide. Depending on the proportion of carbon monoxide in the air and the duration

the impact of the driver's work in such an atmosphere varies.

The most characteristic signs with minor poisoning are drowsiness, fatigue, intellectual passivity, impairment

spatial coordination of movements, errors in determining the distance and an increase in the latency period in sensorimotor reactions. Studies have shown that only a small

amount of carbon monoxide to make some people feel stupefied, intoxicated, headache, sleepy, and disorientated. such deviations that can lead to a run off the road, an unexpected turn of the steering wheel, falling asleep.

Carbon monoxide is sucked into the passenger compartment along with exhaust gases in case of technical malfunctions of the car. Free from any odor and color, carbon monoxide remains completely

imperceptible. In this case, a working person is poisoned three times faster than a person who is at rest.

It should be borne in mind that carbon monoxide also enters the driver's workplace together with the exhaust gases emitted by engines of other vehicles. This is especially dangerous for drivers of passenger cars - taxis, city buses and trucks, systematically working in conditions of heavy and heavy traffic in cities, the highways of which are filled with exhaust gases.

Studies of the air in the cabins of drivers and in passenger cabins of buses showed that in some cases the content of carbon monoxide reaches 125 mg / m3, which is several times higher than the maximum permissible concentration for the driver's working area. Therefore, driving a car for more than 8 hours in a city is extremely dangerous due to the possibility of poisoning the driver with carbon monoxide.

Conditions in which a person does not experience overheating or hypothermia, sudden air movement and other unpleasant sensations can be considered thermally comfortable. Comfortable conditions in winter are somewhat different from those in summer, which is associated with the use of different clothes by a person. The main factors that determine the thermal state of a person are temperature, humidity and air speed, temperature and properties of the surfaces surrounding a person. With various combinations of these factors, it is possible to create equally comfortable conditions in the summer and winter periods of operation. In view of the variety of features of heat exchange between the human body and the external environment, the choice of a single criterion that characterizes comfortable conditions and is a function of environmental parameters is a difficult task. Therefore, comfortable conditions are usually expressed by a set of indicators that limit individual parameters: temperature, humidity, air speed, maximum air temperature difference in the body and outside, temperature of surrounding surfaces (floor, walls, ceiling), radiation level, air supply to a confined space (body , cabin) per person per unit of time or air exchange rate.

The comfortable values \u200b\u200bof air temperature and humidity, recommended by various researchers, are somewhat different. So, the Institute of Hygiene

doing light work, the air temperature in winter

20 ... 22 ° С, in summer +23 ... 25 ° С at a relative humidity of 40 ... 60%.

The permissible air temperature is + 28 ° С at the same humidity and its low speed (about 0.1 m / s).

According to the results of French researchers, for light winter work, the recommended air temperature is +18 ... 20 ° C with a humidity of 50 ... 85%, and

for summer +24 ... 28 ° С with air humidity 35 ... 65%.

According to other foreign data, car drivers must work at lower temperatures (+15 ... 17 ° C in the winter period of operation and

18 ... 20 ° С in summer) at a relative humidity of 30 ... 60% and

the speed of its movement is 0.1 m / s. In addition, the temperature difference between the outside air and inside the body during the summer period should not exceed 10 ° C. The temperature difference inside the limited volume of the body in order to avoid colds in humans should not exceed 2 ... 3 ° C.

Depending on the working conditions, to ensure comfortable conditions, the temperature in winter can be taken equal to + 21 ° С with light

work, + 18.5 ° С at moderate, + 16 ° С at heavy.

Currently, in Russia, microclimatic conditions on cars are regulated.

So, for cars, the air temperature in the cab (body) in the summer period should not be higher than +28 C, in winter (at an outside temperature of –20 ° C) - not less than + 14 ° C. In summer, when driving at a speed of 30

km / h the difference between the internal and external air temperature at the driver's head level should not be more than 3 ° С at an external temperature of + 28 ° С and more than 5 ° С at an external temperature of + 40 ° С. In winter, in the zone

the position of the driver's legs, waist and head should be at a temperature not lower than + 15 ° С at an external temperature of –25 ° С and not lower than + 10 ° С at an external temperature of –40 ° С.

Air humidity in the cabin should be 30 ... 70%. The supply of fresh air to the cab must be at least 30 m3 / h per person, the air speed in the cab and the car interior must be 0.5 ... 1.5 m / s. The maximum concentration of dust in the cabin (cabin) should not exceed 5 mg / m3.

Ventilation system devices must create an overpressure of at least 10 Pa in a closed cabin.

The maximum concentration of dust in the cab (passenger compartment) should not exceed 5 mg / m3.

The maximum permissible concentration of harmful substances in the air of the working areas of the passenger compartment and cabin of the car is regulated by GOST R 51206 - 98 for cars, in particular: carbon monoxide (CO) - 20 mg / m3; nitrogen oxides in terms of NO2 - 5 mg / m3; total hydrocarbons (Сn Нm) - 300 mg / m3; acrolein (С2Н3СНО) - 0.2 mg / m3.

The concentration of gasoline vapors in the passenger compartment and cabin of the car should not exceed 100 mg / m3.

The temperature regime in the cab (body) can be approximately

calculated according to the heat balance equation, according to which the air temperature in the cab (body) remains constant:

Heat supply to the cabin from various sources. IN

in most cases, the thermal balance of the cabin (cabin) is determined by a number of factors, the main of which are: the number of people in the cabin (cabin) and

quantity of heat

QCh coming from them; quantity of heat,

coming through transparent barriers

(mainly from

solar radiation) and opaque fences

(quantity of heat,

coming from the engine

QДВ, transmissions

QTP, hydraulic equipment

electrical equipment with a fan.

In this way,

QEO) and together with external air

QVN supplied

ΣQi  QCh  QCh П QP.O  QNP.O  QDV  QTR  QGO  QEO  QVN  0

It should be noted that the terms of the heat balance included in the equation should be taken into account algebraically, i.e. with a positive sign when heat is released into the cabin and with a negative sign when it is removed from the cabin. Obviously, the heat balance condition is satisfied if the amount of heat entering the cabin is equal to the amount of heat removed from it.

Temperature conditions and air mobility in car cabins are provided by heating, ventilation and air conditioning systems.

Currently, there are various ventilation and heating systems for cabins and car interiors, differing in the layout and design of individual units. The most economical and widely used on

modern cars are heating systems that use the heat of liquid cooling the engine. The combination of heating systems and general ventilation of the cab allows to increase the efficiency of the entire complex of devices for ensuring the microclimate in the cab throughout the year.

Heating and ventilation systems differ mainly in the location of the air intake on the outer surface of the car, the type of fan used and its location relative to the radiator

heater (at the inlet or outlet of the radiator), the type of radiator used (tubular-plate, tubular-tape, with an intensified surface, matrix, etc.), the control method

heater operation, presence or absence of a bypass air duct,

recirculation channel, etc.

Air intake from outside the cab into the heater is carried out in the place of minimum dust content and maximum dynamic pressure,

arising from the movement of the car. In trucks, the air intake is located on the roof of the cab. Water-reflecting partitions, blinds and covers are installed in the air intake,

driven from inside the cab.

To provide air supply to the cabin and overcome the aerodynamic resistance of the radiator and air ducts, an axial fan is used,

radial, diametrical, diagonal or other type. Currently, the most widespread is a double-cantilever radial fan, since it has relatively small dimensions with a large

productivity.

DC motors are used to drive the fan. The rotational speed of the electric motor and, accordingly, the fan impeller is controlled by a two- or three-stage variable resistor included in the electric motor power supply circuit.

The heat output of the heater and its heat depends on the structural and technological design of the heat transfer surface of the radiator.

aerodynamic drag. To increase the efficiency of heat transfer from the radiator, the shape of its channels through which the air moves is complicated, and various turbulators are used.

The air diffuser plays a decisive role in the efficient and uniform distribution of temperatures and air velocities in the cab. The air distributor nozzles are of various shapes: rectangular,

round, oval, etc. They are placed in front of the windshield glass, near the glass doors, in the center of the instrument panel, at the driver's feet and in other places determined by the requirements for the distribution of supply air

flows in the cockpit.

Various dampers, rotary blinds,

control plates, etc. The drive to the dampers and rotary louvers is most often located directly in the air distributor housing.

Air ducts to the air distributor are made of sheet steel, rubber hoses, corrugated plastic pipes, etc. IN

some cars use cabin parts as air ducts, the cavity of the instrument panel. However, such a design of air ducts is irrational, since tightness is not ensured and air consumption increases. Vehicle traffic safety is largely

depends on reliable and effective protection of the windshield from fogging and freezing, which is achieved by uniformly blowing warm air and heating it to a temperature above the dew point.

Such glass protection is structurally simple, does not impair its optical properties, but requires an increase in the performance of the ventilation system and high heat capacity of the glass. The effectiveness of the jet glass protection against

fogging is determined by the temperature and air velocity at the exit from the nozzle located in front of the glass edge. The higher the air velocity at the outlet of the nozzle, the less the temperature in the glass zone differs from

temperature at the outlet of the nozzle.

The layout of the ventilation and heating system depends on the design of the car, cab, individual units and their location.

Currently, air conditioners are widespread - devices for

artificial cooling of air entering the cab (body). According to the principle of operation, air conditioners are divided into compression, air-cooled, thermoelectric and evaporative. Automatic control of the heater operating mode in some vehicles is performed by changing the flow rate of fluid or air through the heater radiator. With automatic regulation by changing

air flow rate parallel to the radiator, a bypass air channel is made, in which a controlled damper is installed.

As already noted, an important place in the ventilation system of the cab (body)

the car is occupied by cleaning the ventilation air from dust.

The most common way is to clean the ventilation air using filters made of cardboard, synthetic fiber materials,

modified polyurethane foam, etc. However, for the effective use of such filters, which are characterized by low dust holding capacity, with a smaller number of maintenance, it is necessary to reduce

dust concentration at the filter inlet. For preliminary air purification, dust separators of inertial type are installed at the filter inlet with continuous removal of captured dust.

The basic principles of dedusting ventilation air are based on the use of one or more mechanisms for the deposition of dust particles from the air: the inertial separation effect and the effects of entanglement and

deposition.

Inertial deposition is carried out with a curvilinear movement of dusty air under the action of centrifugal and Coriolis forces. On

the deposition surface is discarded such particles whose mass or velocity is significant and they cannot follow with the air along the flow line around the obstacle. Inertial settling is manifested and

when the obstacles are elements of filter filling made of fibrous materials, ends of flat sheets of inertial louvres, etc.

When dusty air moves through a porous partition, particles

suspended in the air, stay on it, and air completely passes through it. Studies of the filtration process are aimed at establishing the dependence of the dust collection efficiency and aerodynamic resistance on the structural characteristics of porous partitions, the properties of dust and the air flow regime.

The air purification process in fiber filters takes place in two stages.

At the first stage, the particles are deposited in a clean filter without structural changes in the porous partition. In this case, changes in the thickness and composition of the dust layer are insignificant and can be neglected. At the second stage, continuous structural changes in the dust layer and further deposition of particles in significant quantities occur. At the same time, the efficiency of dust collection of the filter and its aerodynamic resistance change, which complicates the calculation of the filtration process. The second stage is complex and poorly studied; in operating conditions, it is it that determines the efficiency of the filter, since the first stage is very short-lived. Of the whole variety of filtering materials used in the filters of the ventilation air dedusting system of cabins, three groups can be distinguished: woven from natural, synthetic and mineral fibers; non-woven - felt, paper, cardboard, needle-punched materials, etc.; cellular - polyurethane foam, spongy rubber, etc.

For the manufacture of filters, materials of organic origin and artificial are used. Organic materials include cotton, wool. They have low heat resistance, high moisture capacity. A common disadvantage of all filtering materials of organic origin is their susceptibility to putrefactive processes and the negative effect of moisture. Synthetic and mineral materials include: nitron, which is highly resistant to temperatures, acids and alkalis; chlorane, which has low thermal stability but high chemical resistance; nylon, characterized by high abrasion resistance; oxalon having high heat resistance; fiberglass and asbestos, which are characterized by high heat resistance, etc. The filter material made of lavsan has high indicators of dust-collecting, strength and regeneration parameters.

Non-woven needle-punched lavsan are widely used in filters with impulse air blowing during filter regeneration.

filtering materials. These materials are obtained by compaction of fibers, followed by needling or needling.

The disadvantage of such filter materials is the passage of more

fine dust particles through the holes formed by the needles.

A significant drawback of filters made of any filter material is the need for replacement or maintenance in order to

regeneration (recovery) of the filter material. Partial regeneration of the filter can be carried out directly in the ventilation system by backflushing the filter material with purified air from the car cab or by local jet blowing with air

from a compressor with preliminary cleaning of compressed air from water and oil vapors.

Filter construction made of woven or non-woven filter materials

for cab ventilation systems, it must have a maximum filtration surface with minimum dimensions and aerodynamic resistance. The installation of the filter in the cabin and its change should be convenient and ensure reliable tightness around the filter perimeter.

1.13.2. Vibration comfort

From the point of view of reaction to mechanical excitations, a person is a kind of mechanical system. At the same time, various internal organs and individual parts of the human body can be considered as masses, interconnected by elastic bonds with the inclusion of parallel resistances.

Relative movements of parts of the human body lead to stresses in the ligaments between these parts and mutual collision and pressure.

Such a viscoelastic mechanical system has natural frequencies and rather pronounced resonance properties. Resonant

the frequencies of individual parts of the human body are as follows: head - 12 ... 27 Hz,

throat - 6 ... 27 Hz, chest - 2 ... 12 Hz, legs and arms - 2 ... 8 Hz, lumbar spine - 4 ... 14 Hz, abdomen - 4 ... 12 Hz. The degree of harmful effects of vibrations on the human body depends on the frequency, duration and direction of vibration, individual characteristics of a person.

Long-term vibrations of a person with a frequency of 3 ... 5 Hz have a harmful effect on the vestibular apparatus, the cardiovascular system and cause motion sickness syndrome. Vibrations with a frequency of 1.5 ... 11 Hz cause disturbances due to resonant vibrations of the head, stomach, intestines and ultimately the whole body. With vibrations with a frequency of 11 ... 45 Hz, vision deteriorates, nausea, vomiting occurs, and the normal activity of other organs is disrupted. Oscillations with a frequency of more than 45 Hz cause damage to the vessels of the brain, a disorder of blood circulation and higher nervous activity occurs with the subsequent development of vibration disease. Since vibration with constant exposure has an adverse effect on the human body, it is normalized.

The general approach to vibration normalization is to limit vibration acceleration or vibration velocity measured at the driver's workplace in

depending on the direction of the vibration, its frequency and duration.

Note that the smooth running of the machine is characterized by general vibration,

transmitted through the support surfaces to the body of a seated person. Local vibration is transmitted through the hands of a person from the controls of the machine, and its effect is less significant.

Dependence of the mean square value of the vertical

the vibration acceleration az of a seated person from the vibration frequency with his constant vibration load is shown in Fig. 1.13.1 (curves of "equal concentration"), from which it can be seen that in the frequency range f \u003d 2 ... 8 Hz the sensitivity of the human body to vibration increases.

The reason for this is precisely the resonant vibrations of various parts of the human body and its internal organs. Most curves

"Equal thickening" are obtained when the human body is exposed to harmonic vibration. In case of random vibration, the curves of "equal concentration" in different frequency ranges have a general character, but

quantitatively differ from harmonic vibration.

Vibration hygienic assessment is carried out by one of three methods:

frequency (spectral) analysis; integral estimate of frequency and

"Dose of vibration".

In a separate-frequency analysis, the normalized parameters are the root-mean-square values \u200b\u200bof the vibration velocity V and their logarithmic levels Lv or vibration acceleration az for local vibration in octave frequency bands, and for general vibration in octave or one-third octave frequency bands. When normalizing vibration, “equal thickening” curves were first taken into account in ISO 2631-78. The standard establishes the permissible root-mean-square values \u200b\u200bof vibration acceleration in one-third octave bands

frequencies in the range of geometric mean frequencies of 1 ... 80 Hz with different duration of vibration. ISO 2631-78 provides for the assessment of both harmonic and random vibration. In this case, the direction of the general vibration is usually estimated along the axes of the orthogonal coordinate system (x - longitudinal, y - transverse, z - vertical).

Figure: 1.13.1. Curves of "equal concentration" at harmonic vibration:

1 - the threshold of sensations; 2 - the beginning of unpleasant sensations

A similar approach to vibration regulation is used in GOST

12.1.012-90, the provisions of which are the basis for determining the criterion and indicators of the smoothness of the vehicle.

As a criterion for smooth running, the concept of "safety" was introduced, not

causing health problems for the driver.

Smoothness indicators are usually assigned by the output value, which is the vertical vibration acceleration az or the vertical vibration velocity Vz, determined on the driver's seat. It should be noted here that when assessing the vibration load on a person, vibration acceleration is the preferred output value. For sanitary standardization and control, the vibration intensity is estimated by the mean square

value az

vertical vibration acceleration, as well as its logarithmic

Threshold root mean square

vibration acceleration.

Mean square value az

called "controlled

parameter ", and the smoothness of the machine is determined with constant vibration in the frequency range 0.7 ... 22.4 Hz.

With the integral assessment, a frequency-corrected value of the controlled parameter is obtained, with the help of which the ambiguity of a person's perception of vibration with a different spectrum is taken into account

frequencies. Frequency-corrected value of monitored parameter az

and its logarithmic level

are determined from the expressions:

~ ∑ (k zi a zi);

 10 lg ∑100,1 (Lazi  Lkzj),

- root mean square value of the controlled parameter

and its logarithmic level in the i-th octave or one-third octave band;

- weighting factor for the mean square value

of the controlled parameter and its logarithmic level in the i-th band

kzi i; n is the number of bands in the normalized frequency range.

The values \u200b\u200bof the weighting factors are given in Table 1.13.1.

Table 1.13.1

The average value of the frequency of one-third octave and

Third octave frequency band

Octave frequency band

octave bands

According to sanitary standards, with a shift duration of 8 hours and general vibration, the standard root-mean-square value of vertical vibration acceleration is 0.56 m / s2, and its logarithmic level is 115 dB.

When determining the vibration load on a person using the vibration spectrum, the standardized indicators are the root-mean-square value of vibration acceleration or its logarithmic level in one-third octave and octave frequency bands.

The permissible values \u200b\u200bof the spectral indicators of the vibration load on a person are given in table. 1.13.2.

Table 1.13.2

Sanitary norms of spectral indicators of vibration load for vertical vibration acceleration

geometric

Standard average

square value

Normative

logarithmic

one-third octave frequency

vibration acceleration

vibration acceleration

and octave

Third octave

frequency band

Octave

frequency band

Third octave

frequency band n

In the case of using integral and separate-frequency methods for assessing the vibration load on a person, you can come to different results. As a priority, it is recommended to use the method of split-frequency (spectral) assessment of vibration load.

Currently, the standard indicators of the smoothness of machines, such as vibration acceleration and

vibration velocities in the vertical and horizontal planes, set differentially for different vibration frequencies.

The latter are grouped into seven octave bands with an average geometric frequency from 1 to 63 Hz (Table 1.13.3.).

Table 1.13.3

Standard indicators for the smooth running of transport vehicles

Parameter

Vibration speed,

Average geometric vibration frequency, Hz

1 2 4 8 16 31,5 6

vertical horizontal Vibration acceleration, m / s2: vertical horizontal

On a number of special wheeled and tracked vehicles operated in difficult road conditions, where the amplitudes of the micro-profile are significant, it is difficult to ensure the values \u200b\u200bof the smoothness indicators, regulated for transport equipment. Therefore, for such machines, standard indicators of smoothness are set at a lower level (tab.

Table 1.13.4

Ride standard values \u200b\u200bfor machines operating in severe road conditions

Workplace acceleration

driver - (operator)

Vertical:

mean square maximum from episodic

shocks

maximum from rotary jolts

Horizontal RMS

Transport traction

Ride standards for trucks, buses, cars, trailers and semi-trailers are determined for three types of NAMI auto-range sections:

I - cement dynamometric road with an rms value of the heights of irregularities of 0.006 m;

II - pothole-free cobblestone road with RMS

roughness values \u200b\u200bof 0.011 m;

III - potholed cobblestone road with a rms roughness of 0.029 m.

The standards of smooth running of cars, established by OST 37.001.291-84,

are given in table. 1.13.5, 1.13.6, 1.13.7.

To improve the indicators of the smooth running of cars, the following measures are used:

The choice of the layout of the car, which ensures the independence of vibrations on the front and rear suspensions of the sprung weight of the car;

Selection of the optimal characteristics of suspension elasticity;

Ensuring the optimal ratio of the stiffness of the front and rear suspensions of the car;

Reducing the mass of unsprung parts;

Suspension of the driver's cab and seat of a truck and a road train.

Table 1.13.5

Limiting technical standards for the smooth running of trucks

Corrected values \u200b\u200bof vibration accelerations on seats, m / s2, not more

horizontal

RMS vertical

vibration accelerations in

vertik roads

longitudinal

characteristic points of the sprung part, m / s2, not more

Table 1.13.6

Limiting technical standards for smooth running of passenger cars

Corrected values \u200b\u200bof vibration accelerations in the driver's and

Road type

passengers, m / s2, not more

vertical horizontal

Table 1.13.7

Limiting technical standards of smooth running of buses

Corrected values \u200b\u200bof vibration accelerations on bus seats, m / s2, no more

other urban types

driver passengers driver and passengers

1.13.3. Acoustic comfort

Various noises are generated in the vehicle cab, which adversely affect the driver's performance. First of all, the auditory function suffers, but noise phenomena, possessing cumulative properties (i.e. properties to accumulate in the body), inhibit the nervous system, while psychophysiological functions change, the speed and accuracy of movements are significantly reduced. Noise causes negative emotions, under its influence the driver gets distracted, apathy, memory impairment. Human exposure to noise can be divided into the following groups, depending on the intensity and spectrum of noise:

Very strong noise with levels of 120 ... 140 dB and above - regardless of the spectrum, it can cause mechanical damage to the hearing organs and cause severe damage to the body;

Strong noise with levels of 100 ... 120 dB at low frequencies, above 90 dB at medium frequencies and above 75 ... 85 dB at high frequencies - causes irreversible changes in the hearing organs, and with prolonged exposure it can be

the cause of a number of diseases and, first of all, of the nervous system;

Noise of lower levels of 60 ... 75 dB at medium and high frequencies has a harmful effect on the nervous system of a person engaged in work that requires focused attention, to which work belongs

car driver.

Sanitary standards divide noise into three classes and establish an acceptable level for them:

Class 1 - low-frequency noise (the largest components in the spectrum are located below the frequency of 350 Hz, above which the levels decrease) with an allowable level of 90 ... 100 dB;

Class 2 - mid-frequency noise (the highest levels in the spectrum

located below 800 Hz, above which the levels decrease) with an allowable level of 85 ... 90 dB;

Class 3 - high-frequency noise (the highest levels in the spectrum are located above 800Hz) with an acceptable level of 75 ... 85 dB.

Thus, noise is called low-frequency when the vibration frequency is not

more than 400 Hz, mid-frequency - 400 ... 1000 Hz, high-frequency - more

1000 Hz. In this case, according to the frequency of the spectrum, the noise is classified into broadband, which includes almost all frequencies of sound pressure (the level is measured in dBA), and narrowband (the level is measured in dB).

Although the frequency of acoustic sound vibrations is in the range of 20 ... 20,000

Hz, its normalization in dB is carried out in octave bands with a frequency of 63 ...

8000 Hz constant noise. The characteristic of non-constant and broadband noise is equivalent in energy and perception

human ear sound level in dBA.

Permissible internal noise levels for motor vehicles according to

GOST R 51616 - 2000 are given in table. 1.13.8.

It should be noted that the permissible levels of internal noise in the cab or passenger compartment are established regardless of whether there is a single source.

noise or several. Obviously, if the sound power emitted by one source meets the maximum permissible sound pressure level at the workplace, then when installing several such sources

the specified maximum permissible level will be exceeded due to the addition of their effects. As a result, the overall noise level is determined by the energy summation law.

Table 1.13.8

Permissible levels of internal noise from vehicles

Permissible

Motor vehicle

Cars and buses for transporting passengers

sound level, dB A

M 1, except for wagon models or

half-hood body layout

M 1 - models with wagon or 80

semi-hood body layout.

M 3, except for models with

engine location in front of or near

driver: 78 in the driver's workplace 80 in the passenger compartment of class II buses 82

in the passenger compartment of class I buses

Models with 80 layout

engine in front of or near the driver's seat:

at the driver's workplace and in the passenger 80

premises

Trucks for transportation of goods

N1 with gross weight up to 2 t 80

N1 with gross weight from 2 to 3.5 t 82

N3, except for models

destined for international and 80

intercity transportation

Models for international and 80

intercity transportation

Trailers for the carriage of passengers 80

Total noise level, dBA, from several identical sources

LΣ  L1  10 lg⋅ n,

L1 — noise level of one source, dBA;

n is the number of noise sources.

With the simultaneous action of two sources with different sound pressure levels, the total noise level

LΣ  La  ∆L,

- the largest of the two summed noise levels;

∆L - additive depending on the difference in noise levels of two sources

∆L values

depending on the difference in noise levels of the two sources

\u003e Lb) are shown below:

La - Lb, dBA ... ..0 1
∆L, dBA ... ... 3 2.5

It is obvious that if the noise level of one source is higher than the level of another by

8 ... 10 dBA, then the noise of a more intense source will prevail, since

in this case, the addition ∆L

very small.

The total noise level of sources of different intensity is determined by the expression

−0,1∆L1, n 

Σ  1  10 lg 1  10

 ...  10 ,

L1 - the highest noise level of one of the sources;

∆L1, 2 - L1 - L2;

∆L1,3  L1 - L3; ∆L1, n  L1 - Ln ⋅ L2, L3, ...., Ln 

Noise levels

respectively 2nd, 3rd, ..., nth sources). Calculation of the noise level, dB A,

with a change in the distance to the source is performed according to the formula

Lr  Lu - 201gr - 8,

- source noise level; r is the distance from the noise source to

the object of his perception, m.

The general noise of a moving car consists of noise generated by the engine, aggregates, car body and its components, noise of auxiliary equipment and tire rolling, as well as noise from the air flow.

Noise in a specific source is generated by certain physical phenomena, among which the most characteristic in a car are:

impact interaction of bodies; friction of surfaces; forced vibrations of rigid bodies; vibration of parts and assemblies; pressure pulsation in pneumatic and hydraulic systems.

In general, the sources of vehicle noise can be divided into the following:

Mechanical - internal combustion engine, body parts,

transmission, suspension, panels, tires, tracks, exhaust system;

Hydromechanical - torque converters, fluid couplings, hydraulic pumps,

hydraulic motors;

Electromagnetic - generators, electric motors;

Aerodynamic - intake and exhaust system of an internal combustion engine, fans.

Noise has a complex structure and consists of the noise of individual sources. The most intense sources of noise are:

structural engine noise (mechanical and combustion noise), intake and system noise, exhaust and exhaust system noise, cooling fan noise, transmission noise, tire rolling noise (tire noise), body noise. Many years of research have established that the main sources of noise generation in a car include the internal combustion engine, transmission elements, tires, aerodynamic noise. A secondary source of noise is body panels. Additional sources include noises from engine attachments, some transmission elements, electric motors, heaters, windshield blowing, doors slamming, etc.

The listed sources generate mechanical and acoustic vibrations, different in frequency and intensity. The nature of the frequency spectrum

disturbances are very difficult to analyze due to the overlap and interconnection of the frequencies of the working processes and disturbances from the elements of the transmission, chassis, aerodynamic processes, etc.,

and also due to the fact that many sources are simultaneously causative agents of mechanical and acoustic vibrations. The vibration spectra of the main transmission units and noise show up mainly

harmonic components from main sources of excitation

(engine and transmission).

The dynamic interaction of parts of vehicle units generates vibrational energy, which, spreading from vibration sources,

creates a sound field of a car, a tractor, i.e. car noise.

Accordingly, the following paths can be identified to reduce the noise intensity:

Reducing the vibration activity of the units, i.e. reducing the level of vibrational energy generated in the source;

Taking measures to reduce the intensity of vibrations on their way

distribution;

Influencing the process of radiation and transmission of vibrations to attached parts, i.e. decrease in their vibroacoustic activity.

Reducing the vibration activity of the source is achieved by improving the kinematic properties of vehicle systems and choosing the parameters of mechanical systems so that their resonant frequencies are

are maximally removed from the frequency range containing the operating frequencies of the units, as well as by reducing to a minimum the levels of oscillations at the reference points and minimizing the amplitudes of forced oscillations. Reducing noise can be achieved by creating a low-noise process

combustion, improving the vibroacoustic characteristics of body parts, units, introducing damping into their design, improving the design and manufacturing quality of movable

parts, increasing the acoustic efficiency of intake and exhaust silencers, etc.

Fight noise and vibration propagation in the process

radiation and transmission of vibrational energy to attached parts and

units can be performed by "detuning" the system of bearing elements from resonance states by means of vibration isolation, vibration damping and vibration damping.

Vibration isolation - the choice of such parameters of mechanical systems that ensure the localization of vibrations in a certain area of \u200b\u200bthe car without

its further distribution.

Vibration damping - the use of systems that actively dissipate the vibration energy of vibrating surfaces, as well as the use of materials with a large decrement

attenuation.

Vibration damping - application in units tuned to a certain frequency and mode of vibration, systems operating in antiphase.

Suppression of noise at its source is an active method of noise suppression and the most radical means of dealing with noise. However, in many cases, this method, for one reason or another, does not

can be applied. Then you have to resort to passive methods of noise protection - vibration damping of surfaces, sound absorption, sound insulation.

Soundproofing refers to the reduction of sound (noise) to the receiver due to reflection from obstacles in the transmission path. The sound insulating effect always occurs when the sound

waves across the interface between two different media. The greater the energy of the reflected waves, the less the energy of the transmitted waves, and, therefore, the greater the sound insulating ability of the interface. The more sound energy is absorbed by the obstacle, the higher its sound-absorbing

ability.

Noise caused by medium and high frequency vibrations is transmitted to the passenger compartment mainly through the air. To reduce this transmission, a special

attention should be paid to sealing the cabin, identifying and eliminating acoustic holes (acoustic holes). Acoustic holes can be through and non-through slots, technological holes, areas with

low sound insulation, significantly worsening the overall sound insulation of the structure.

From the point of view of the features of the transmission of sound energy, they are distinguished

large and small acoustic holes. A large acoustic hole is characterized by a large, in comparison with unity, ratio of the linear dimensions of the hole to the length of the sound wave incident on the hole. In practice, it can be assumed that sound waves pass through a large acoustic hole according to the laws of geometric acoustics and that the sound energy passed through the hole is proportional to its area. For each category of holes, there is one or more effective remedies.

To determine effective ways to reduce noise, it is necessary to know the most intense noise sources, to separate them, and also

determine the need for and the magnitude of the reduction in the levels of each of them

Having the results of the separation of sources and their levels, it is possible to determine the sequence of tuning the car for noise.

test questions

1. For what purpose is the safety of the vehicle structure regulated?

2. What are the main properties that determine the safety of the structure of vehicles

3. By what criteria is the impact of active vehicle safety on road safety determined?

4. What is the relationship between vehicle weight and risk

getting injured in an accident for his passengers?

5. What determines the width of the dynamic corridor during curved motion?

6. What size classes are cars sold in Europe divided into?

with GOST R 52051-2003?

8. What forces act on a car accelerating uphill?

9. What changes in the technical condition of the car affect its traction dynamics and how?

10. What is the dynamic factor of a car?

11. What is called the lateral stability of a car?

12. What is called the longitudinal stability of a car?

13. What is vehicle directional stability?

14. What are the main technical requirements (test methods)

impose on the braking properties of vehicles?

15. What standards regulate the stability and controllability of vehicles as active safety properties?

16. What types of resistance tests do you know?

17. What indicators are assessed in the "stabilization" test?

18. What types of car steering are there?

19. For what technical reasons is it possible to lose controllability of the car?

20. What is the stopping distance of a car?

21. How is the Type 0 test of vehicle braking systems carried out?

22. What indicators determine the requirements for tires and wheels?

23. Indicate the main characteristics of the coupling devices.

24. What devices are used for information support of vehicles?

25. What are the technical requirements for lighting and light signaling devices?