How the machine works on. Principle of operation of an automatic transmission. The principle of functioning of the "Automatic" box

Modern cars are equipped with several types of transmissions. Domestic cars Until recently, a manual gearbox was mainly completed. With a box, Russian motorists met, after the country began to import cars from abroad. But with the variator, there are still few people come across. The wide distribution of this type of transmission is just beginning.

So arranged variator

Principle of operation of the variator

The variator was invented for a long time. A description of the basic principles of his work is occurring in the notes of Leonardo da Vinci dated to the end of the fifteenth century. The first cars with the variator appeared in the fifties of the last century. These were small DAF. Then this transmissary began to equip some Volvo models. But the variator never received wide distribution at that time. And only today, the developers again began to develop and actively implement this type of transmission into production.

The principle of operation of a variator or CVT (abbreviation from English Continuously Variable Transmission) is radically different from classical mechanics and machine gun. It does not take fixed gear. Switching speeds from the first to the second, etc. absent. The transfer ratio from the engine shaft to the wheel drive varies smoothly as overclocking or slowing the car. Modern cars are equipped with toroidal, chain and clinorenic variasts. The most common type of transmission is most common.

Consider the principle of operation of a variator with a clinorem

The effect of cone-shaped halves of pulley leads to the poverty of the belt to the outer diameter, and the extension to the movement towards the axis

The basis of the clinoremable variator is two pulley. Each pulley consists of a pair of cones facing vertices to each other. Shifting and sliding cones allows you to change the diameter of the pulley. Pulleys are connected by a wedge-shaped belt. The flow of cone-shaped halves of pulley leads to the poverty of the belt to the outer diameter, and the expansion to the move towards the axis. Thus, smoothly changes the radius, according to which the belt works - from smaller to more and vice versa. Accordingly, the gear ratio of the engine varies and the drive. If the lead and slave pulleys are in an intermediate position (the diameters of the pulleys are equal), the transmission becomes direct - the frequency of rotation of the motor shaft is equal to the speed frequency of the drive.

To start the machine from the scene there is a conventional clutch or a torque converter, which is blocked after the start of movement. Drills of pulleys controls the electronic system consisting of servo drive, sensors and control unit.

An important role in this transmission is played by such a detail as a variator belt. Obviously, the usual rubber belt, from those that are used in the actuators of the air conditioner or the generator, is not suitable here. It will not withstand loads arising from the transmission of the torque in the variator, and is quickly extended. Therefore, the wedge-shaped belt of the variator has a rather complicated structure. This can be a steel tape with a special coating or a set of cables, which are riveted with a plurality of steel plates of the trapezoidal form.

Belt variator

In the cars of the Audi brand, variators with a belt made in the form of a wide steel chain. Special fluid is used for lubrication chain. With a strong pressure in places of contact of the chain with a pulley, it changes its condition. This allows the chain to transmit great efforts without slippage.

Variator - pros and cons

The benefits of a vehicle with a variator can be attributed smooth and at the same time quite fast overclocking. Comfortable ride on the variator is comparable to a ride on - in the car also provides for only two pedals and there is no need to manipulate the speed switching lever. This is especially true for novice drivers. The engine with a variator transmission will not silent on the traffic light and will not give the car back on the cool rise.

Thanks to the variator, the load on the drive elements and the engine is distributed evenly with any driving style. The engine with the variator always works smoothly, in a favorable gentle mode. It greatly increases its resource, reduces fuel consumption, reduces the emission of harmful substances into the atmosphere.

Disadvantages of the variator:

• Horregious transmission fluid and the inability to replace it with ordinary oil
• Dorganiza repair and lack of narrow-profile qualified specialists
• The need to remove indications with a large number of different sensors. If you fail, even one of them has serious violations in the work of the entire transmission
• Inability to install on cars with a powerful engine

Although it is worth noting that there are some progress on the equipment of the variator transmission of more powerful engines. For example, on Audi A4 2.0 TFSI (engine power 200 hp) a variator with a Multitronic chain is successfully operating. BUT crossover Nissan. Murano with a 3.5 liter engine and a capacity of 234 hp Equipped with an X-Tronic clinoremable variator. If the variator is still unacceptable for trucks, then for passenger cars It is a good alternative mechanic or machine.

In this video detailed review automatic transmissions

What is better - a variator or machine

Many motorists ask themselves the question - what better variator Or machine? Short description The principle of operation of the variator was given above. Therefore, how is the variator differ from the machine quite understandable. But is such a transmission better than the automatic transmission - there is no unambiguous answer. With the advantages of the variator compared to the machine, everything is clear. This is a dynamic acceleration, and low fuel consumption, and a larger engine resource. But here is that there is still a box of automatic in the win. Although it is impossible to say that repair automatic transmission The lowest, however, it will cost cheaper than similar work with the variator. Yes, and services providing services for the repair of automatic transmission significantly more.

Variator or mechanic what is better

The same question may occur in relation to the manual transmission - a variator or mechanic, what is better? According to the advantages of the variator, the situation here is the same as with a machine gun. Regarding the repair and maintenance of the mechanics, it is definitely cheaper than the variator and the machine. It will not be superfluous to notice that the variator, as well as the machine, is designed rather for lovers of calm safe Movement. Those who belong to the car, first of all, as to the means allowing to quickly move from point A to point B. For the same drivers who simply love cars and all that is connected with them, which you like to feel one whole with your iron horse , I like to join the seat under the action of the load from acceleration, you like to hear the root of the motor - the answer to the question of a variator or mechanic that it will be better to be unequivocal - MCPP.

Something useful for you:

Tips for buying and maintaining a car with a variator

In connection with expensive service And the repair of cars equipped with a variator, when buying it is recommended to give preference to new cars with a guarantee. In the case of used auto, it is difficult to judge the degree of wear of the transmission elements. Repair of a faulty box may require additional costs, so such that the total amount spent on the purchase and repair of a used car will be commensurate with the purchase of a new one.

Motorists are still decided on acquisition with the variator, you should know how to check the variator when buying. The easiest test is to warm up the car and move from the scene. Jews at the start should not be. If they are present, most likely produced a resource of transmission fluid. It must be changed. When replacing the liquid, filters change. When checking the variator in all modes of transmission operations, there should be no extraneous noise.

When buying a car, there may be a question, and what is actually sold by the variator or maybe a classic machine? How to determine the machine or the variator is under the hood? The fact is that visually define the type of transmission is quite difficult. Even the designations of the switch modes in the machine and the variator are the same - P, R, N, D.

Determine the variator or machine can be as follows:

• Carefully familiarize yourself with the documentation for the car - the machine is denoted by the letters at or A. Variator - CVT
• Collect information about a specific car brand from reference books, directories, on the Internet. Thus, you can find out which type of transmission is installed on the car you are interested in
• Conduct a test trip by car. With a dynamic acceleration, the machine, switching transmission, gives tangible shoes. Simultaneously with the switching changes and the number of revolutions, which can be determined by a tachometer or hearing. The variator accelerates without shocks at the stationary tachometer arrow.
• In some new variator models, there is no probe to check the gearbox oil level. In automatic boxes, the dipstick is always present.

Car owners with a variator are recommended every 24,000 mileage kilometers to visit the service station to verify the status working fluid. Replacing the oil in the variator is performed every 60 thousand km of run. This is according to the manufacturer's instructions, but on the recommendations of specialists it is better to make a fluid replacement earlier in 30 - 40 thousand km.

How to ride the variator

• At negative temperatures, it is not recommended to give a greater load on the transmission immediately after the start of the movement. Elements of the system must warm up in a small go.
• Try to avoid strong and sharp loads, the variator is not created for racing, towing and off-road.

During operation, you must regularly check the status of the wiring, connectors and sensors. If foreign noise appears, you need to immediately contact the service center. Trying to repair the variator independently, not having skills and special devices, it is not recommended.

To date, most drivers do not represent how they went by car, which does not have an automatic gearbox. Some newbies come terrified from one thought that it would have to constantly switch the transmissions manually. Many drivers with great experience also have long understood that ride with automatic box much more convenient. Despite all this, people tormented the question - how to properly exploit the box automatic? In this article, this will be discussed.

Modes of work

To understand how the automatic box should be operated, you need to deal with what existing modes.

It should be immediately noted that the modes "P", "R", "D" and "N" are mandatory in each box. To select one of the modes, you just need to move the shift lever to the appropriate position. The difference from the manual box is that the movement of the lever occurs on one line.

The mode that the driver selected will be displayed on the control panel. It makes it possible to carefully follow the road and not distracted to look at the lever.

1. "P" - Parking. Used during long parking. It is with parking that it is advisable to start a car. It is important before turning on this mode to completely stop the machine.
2. "R" - used to move with reverse. To enable, you need to stop completely.
3. "N" is a neutral position. When the lever is on the "neutral", the torque is not transmitted to the wheels. It is worth using in a period of minor stops.
4. "D" - movement. When the selector is in this position, the car goes forward. Shift shift is performed independently. The driver is just taking a gas pedal.

In the car, which installed five - or four-stage box, the selector has several positions for moving forward: "D", "d3", "d2", "d1". These numbers show upper gear.

1. "D3" - "The first 3 transmissions". It is recommended to use in cases where there is no possibility to move without slowing down.
2. "D2" - "The first 2 transmissions". Translate the lever into such a position when the speed of movement is less than 50 km / h. Most often used on poor-quality roads.
3. "D1" ("L") - "Only 1st Transfer". Used in the event that maximum speed is 25 km / h. Translate the lever to a similar position is when the machine is in traffic.
4. "OD" - "Increased transmission". In such a position should be moved when the speed reaches more than 75 km / h, and leave it when the speed drops below 70 km / h. Increased transmission makes it possible to reduce fuel consumption at the moments of movement in motorways.

Most of the new machines with automatt have several ACAP auxiliary modes. To those can be attributed:

1. "N" is standard, which is used during a regular ride.
2. "E" - fuel economy mode. Helps the car to move at such a pace, which significantly reduces fuel consumption.
3. "S" - Sport. When the driver switches to this mode, it can maximize the power of the motor. Nothing surprising is that fuel consumption in this mode will be high.
4. "W" - winter. It is used in those moments when you need to start moving from slippery road surface.

Of course, there are drivers who could not get used to the automatic transmission, given all its advantages. To satisfy the needs of these people, the "Titonik" regime was created. In essence, he implies a manual control imitation. On the box, it is implemented in the form of a groove for the selector, and marked with signs plus and minus. Plus makes it possible to increase the transfer, and minus - downgrade, respectively.

Basic operating conditions automatic

In order to start moving by the machine in which the automatic box is installed, the actions should be performed in the following order:

• Press the brake pedal.
• Selector Move to the "Drive" position.
• Remove from the handbrake.
• Slowly let go of the brake. The car will start slowly moving.
• Press the accelerator pedal.
• To reduce speed, you need to throw gas. If you need a quick stop, then you need to use the brake.
• To move after a minor stop, you just need to move the foot from the brake, to the accelerator.

The main rule of using automatic transmission is to avoid sharp maneuvers. If you constantly do to them, it will increase the gap between the friction disks, and then in the differential. All this will lead to the fact that the machine will twitch during each transmission switching.

Experienced masters believe that the machine must be given a short-term "rest." This means that the car needs to be able to move a few seconds to idling. It is worth noting that even in a car with a powerful engine, sharp movements will significantly reduce the resource of the box.

In fact, this moment is very important, because most of Such boxes broke in winter. First of all, this is due to a significant drop in temperature and so that the machines are often touched on ice. In order to maximize their car from breakdown, follow the following recommendations:

• Before the onset of cold weather, check the quality and level of fluid in the box, and if necessary, replace;
• Be sure to warm up the car before starting the movement;
• If the car is stuck, do not harm the gas hoping to leave. It is worth trying to reduce the transfer (if there is such an opportunity) or just push;
• Before a steep turn, use only reduced transmissions.

What not to do

What you should not do by car with an automatic box:

1. First of all, you should not heat the box badly if the car did not warm up to required level. Even if the street plus temperature, the first few kilometers, the movement should be smooth and measured.
2. The automatic transmission "does not like" off-road. Machines with automatic, it is best to travel around the roads with bad coatings. If the "iron horse" is stuck, sometimes it is better to resort to the help of shovel than to put pressure on gas.
3. It is not recommended to expose the automatic transmission to high loads. If there were plans to tow the trailer, it is better to throw them out of the head.
4. It is strictly forbidden to start a car with a so-called pusher. Many people violate this ban, but it is worth remembering that it will not pass without a trace for the box.

Of course, it is impossible to forget about certain features of switching between modes:

• on the "neutral" one can remain only if the brake is pressed;
• on the "neutral", the car is prohibited;
• swimming the motor is permitted exclusively in the Parking position;
• when the car in motion cannot be transferred to the lever in the parking position and the "movement back".

Summing up, it is worth noting that the automatic box may seem pretty "picky" and having a small resource. In fact, if it is competent to exploit it, it will delight your owner for a very long time.

Video: how to use the automatic transmission

Vehicles with an automatic transmission switch every year becomes more and more. And, if we have - in Russia and the CIS - "Mechanics" still continues to prevail in front of the "automatic", then in the west of cars with automatic transmission, now the overwhelming majority. It is not surprising if you take into account the indisputable advantages of automatic boxes: simplifying the car management, stable smooth transitions from one transmission to another, engine protection from overloads, etc. Adverse mode of operation, improving the driver's comfort while driving. As for the shortcomings of this transmission option, modern automatic transmission as it improves gradually get rid of them, make them insignificant. In this publication, about the device of the "automaton" box and all its advantages / minuses in work.

An automatic transmission is called such a type of transmission, which provides automatic, without direct exposure to the driver, select the gear ratio, most of all corresponding to the current vehicle movement conditions. The variator does not apply to the automatic transmission and stands out in a separate (infinitely) transmission class. Because the variator produces changes in the transfer numbers smoothly, in general without any fixed gears.

The idea to automate gear shifting, having robbing the driver from the need to often squeeze the clutch pedal and "work" the switching lever, not Nova. She began to introduce and hurry at the dawn of the automotive era: at the beginning of the twentieth century. Moreover, it is impossible to call any definite man or the company the only creator of the automatic transmission: to the appearance of a classic, which now obtained the universal spread of the hydromechanical automatic transmission has led three initially independent developments lines, which ultimately united in a single design.

One of the main mechanisms of the box-machine is a planetary series. The first serial car equipped with a planetary transmission was released back in 1908, and it was Ford T. Although, in general, the transmission box was not yet fully automatic (from the Ford T driver it was necessary to press two foot pedals, the first of which translated from the lowest to the highest transmission, and the second turned on the reverse), it already allowed much to simplify control, Compared with conventional gearbox for those years, without synchronizers.

Second important moment In the formation of future automatic transmission technology, this is the transfer of a clutch management from the driver to servo drive, embodied in the 1930s of the twentieth century by General Motors. These gear shift boxes were semi-automatic. The first fully automatic gearbox was introduced into production in the 30s of the twentieth century, the Planetary Electromechanical Box "Kotal". She was installed on French cars forgotten brands "Delazh" and "Delea" (existed until 1953 and 1954, respectively).

The car "Delling D8" is a premium class of a pre-war era.

Other auto industrymen in Europe also developed similar system of friction and brake ribbons. Soon, similar automatic transmission was implemented in cars of several more German and British brands, the well-known healthy helicate of which is "Maybach".

Specialists of another famous firm - American Chrysler advanced further than other automakers, introducing hydraulic elements into the design of the CAT, which replaced servo drives and electromechanical controls. Engineers "Chrysler" have developed the first hydrotransformer and hydromefluoride in history, which are now in the design of each automatic gearbox. And the first in the history of the hydromechanical box-machine, similar to the design to modern, on serial cars was introduced by General Motors Corporation.

Automatic transmissions of those years were very expensive and technically complex mechanisms. In addition, not always distinguished reliable and durable work. They could advantageously look only in the era of non-synchronized mechanical gearboxes, controlled by a car with which was enough difficulty demanding from the driver of a well-worked skill. When mechanical gearboxes with synchronizers spread widely, then for the convenience and comfort of the automatic transmission of the level were not very better than them. While the MCPP with synchronizers possessed much less complexity and high cost.

In the late 1980 / 1990s, all major automakers had a computerization of the engine control systems. Similar systems began to apply both speed switching. If the previous solutions were used only hydraulics and mechanical valves, now the fluid flows control the solenoids controlled by a computer. It made the switching smooth and more comfortable, improved efficiency and increased the efficiency of the transmission.

In addition, some cars were introduced "sports" and other additional modes of operation, the ability to manually control the gearbox ("Tiptronic", etc. Systems). The first five- and more stepped automatic transmission appeared. Perfection supplies allowed many box machines to cancel the oil replacement procedure during the operation of the car, since the resource of the oil is filled into its crankcase in the oil plant has become comparable to the resource of the gearbox itself.

Construction of an automatic transmission

Modern box-machine, or "Hydromechanical transmission", consists of:

• torque torque converter (hydrodynamic transformer, GDT);
• planetary mechanism of automatic gear shift; brake tape, rear and front friction - devices that directly switch transmissions;
• control devices (node \u200b\u200bconsisting of a pump, valve box and oil separator).

The torque converter is needed to transmit torque from power aggregate To the elements of the automatic transmission. It is located between the box and the engine, and thus performs the clutch function. The torque converter is filled with the working fluid, which catches and transmits the engine energy into the oil pump itself in the box.

The hydrotransformer consists of large wheels with blades immersed in special oil. Torque transmission is not carried out mechanical device, and with the help of oil flows and their pressure. Inside the torque converter, a pair of paddle machines are located - a centripetry turbine and a centrifugal pump, and between them - the reactor, which is responsible for smooth and stable changes in torque on the drives to the vehicle wheels. So, the hydrotransformer does not contact the driver or with the clutch (it "itself is" the grip).

The pumping wheel is connected to the engine crankshaft, and turbine, with transmission. When the pumping wheel is rotated, the oil threads are spinning the turbine wheel. So that the torque can be changed in wide ranges, a reactor wheel is provided between the pumping and turbine wheels. Which, depending on the car mode, can be either fixed or rotated. When the reactor is fixed, it increases the flow rate of the working fluid circulating between the wheels. The higher the speed of the oil, the greater the impact it has a turbine wheel. Thus, the moment on the turbine wheel increases, i.e. The device "transforms".

But the torque converter cannot convert the rotation speed and the transmitted torque in all the required limits. Yes, and to ensure the movement with reversal, it is also not in force. To expand these capabilities to it and attaches a set of separate planetary gears with a different gear ratio. As if several single-stage gearbox collected in one case.

Planetary transmission is mechanical systemconsisting of several satellite gear, which rotate around the central gear. Satellites are fixed together with a circle-drove. The outer ring gear has an internal gearing with planetary gears. Satellites, fixed on the driver, rotate around the central gear, like planets around the sun (from here and the name of the mechanism - "Planetary Transfer"), the outer gear rotates around satellites. Various gear ratios are achieved by fixing different parts relative to each other.

Brake tape, rear and front friction - directly produce shift gears from one to another. The brake is a mechanism that locks the elements of the planetary row to the fixed body of the automaton. The cluster blocks the moving elements of the planetary row among themselves.

Control systems automatic gearbox There are 2 types: hydraulic and electronic. Hydraulic systems are used on outdated or budget models, and are gradually derived from use. And all modern boxes are "automata" are controlled by electronics.

Life support device for any control system can be called an oil pump. Its drive is carried out directly from the engine crankshaft. The oil pump creates and maintains constant pressure in the hydraulic system, regardless of the rotation frequency of the crankshaft and the loads on the engine. In the event of a pressure deviation from the nominal operation of the automatic transmission, the actual transmission mechanisms are dotted.

The gearbox is determined by the velocity of the vehicle and the load on the engine. To do this, the hydraulic control system provides a pair of sensors: a high-speed controller and a throttle valve, or a modulator. The high-speed pressure regulator or hydraulic speed sensor is installed on the output shaft of the automatic box.

The faster the vehicle is driving, the more the valve opens, and the greater the pressure passing through this valve of the transmission fluid. Intended to determine the load on the engine valve-throttle is connected by a cable or with a throttle valve (if we are talking about gasoline engine) or with the fuel pump lever high pressure (in a diesel engine).

In some cars for supplying pressure on the throttle valve, it is not used, but a vacuum modulator, which is driven by discharge in the intake manifold (with an increase in the load on the engine, the discharge drops). Thus, these valves create such pressure, which will be proportional to the velocity of the vehicle and the engine loading. The ratio of these pressures and allows you to determine the moments of gear shift and blocking the torque converter.

In the "Fishing Moment" of switching the transmission takes part and the valve of the range selection that is connected to the ACP selector lever and, depending on its position, it permits either prohibits the inclusion of certain gears. The resulting pressure that the throttle valve and the high-speed controller creates the corresponding switching valve. Moreover, if the machine accelerates quickly, the control system will turn on the increased transmission later than when overclocking is calmly uniform.

How it's done? The switching valve is under the pressure of the oil from the high-speed pressure regulator on the one hand, and from the throttle valve - on the other. If the machine accelerates slowly, the pressure from the hydraulic velocity valve goes on the increasing, which leads to the opening of the switching valve. Since the accelerator pedal is not completely pressed, the throttle valve does not create a large pressure on the switch valve. If the car accelerates quickly, the throttle valve creates greater pressure on the switch valve, and prevents it from opening. To overcome this opposition, the pressure from the high-speed pressure regulator should exceed the pressure from the throttle valve. But this will happen when a high speed car is achieved than it happens during slow acceleration.

Each switch valve corresponds to a specific level of pressure: the faster the car moves, the more higher transmission turns on. The valve block is a system of channels with valves and plungers located in them. Switching valves are fed by hydraulic pressure on actuators: friction clutches and brake tapes, by means of which the various elements of the planetary row are blocked and, therefore, turning on (off) of various gears.

Electronic control system Just like the hydraulic, uses 2 basic parameters for operation. This is the speed of the vehicle and the load on its engine. But to determine these parameters, not mechanical, but electronic sensors are used. The main ones are working sensors: rotational speed at the input of the gearbox; Rotation frequency at the output of the gearbox; Temperatures of the working fluid; position of the lever of the selector; The positions of the accelerator pedal. In addition, the control unit of the "automat" receives additional information from the engine control unit, and from others electronic systems Car (in particular, from ABS - anti-lock system).

This allows you to more precisely than in the usual automatic transmission, to determine the moments of the need for switching or in the torque of the torque converter. The electronic gear shift program by the character of a speed change at a given load on the engine can easily and instantly calculate the power of resistance to the movement of the car and, if necessary, adjust: enter the appropriate corrections in the switch algorithm. For example, further include increased transmissions on a fully loaded vehicle.

Otherwise automatic transmission with electronically control Just as the usual, "not burdened by electronics" hydromechanical boxes, use hydraulics to turn on the couplings and brake ribbons. However, they have each hydraulic circuit is controlled by an electromagnetic, not a hydraulic valve.

Before starting the movement, the pump wheel rotates, the reactor and turbine remain in a stationary state. The reactor wheel is fixed on the shaft by means of an overtaking coupling, in connection with which it can only rotate in one direction. When the driver turns on the gear, presses the gas pedal - the engine turns grow, the pump wheel is gaining momentum and oil fluxes the turbine wheel.

The oil dropped back into the turbine wheel falls on fixed reactor blades that additionally "twisted" the flow of this fluid, increasing its kinetic energy, and direct on the blades of the pumping wheel. Thus, with the help of the reactor, the torque increases, which is required by the vehicle, gaining acceleration. When the car accelerates, and started moving at a constant speed, then the pumping and turbine wheels rotate approximately with the same turnover. Moreover, the flow of oil from the turbine wheel falls on the reactor blades already on the other hand, thanks to which the reactor begins to rotate. The increase in torque does not occur, and the torque converter enters the uniform hydromeflua mode. If the resistance of the car's movement began to increase (for example, the car began to ride on the rise, uphill), then the speed of rotation of the leading wheels, and, accordingly, the turbine wheel, falls. In this case, oil streams again slow down the reactor - and the torque increases. Thus, automatic torque control is performed, depending on changes in the mode of motion of the vehicle.

The absence of a rigid connection in the hydrotransformer has both advantages and disadvantages. Pluses are that the torque varies smoothly and steplessly, the tweaks are damped and jerks, transmissions transmitted from the engine. Cons consist primarily in low efficiency, since a portion of useful energy is simply lost when "shocking" oil fluid and spent on the drive of the automatic transmission pump, which ultimately leads to an increase in fuel consumption.

But to smooth this shortage in the hydrotransformators of modern automatic transfers, the lock mode is used. With the steady mode of movement on higher transmissions, the mechanical locking of the hollows of the torque converter automatically turns on, that is, it begins to perform the function of the usual classic clutch mechanism. It provides a hard direct connection of the engine with leading wheels, as in a mechanical transmission. On some automatic transmission, the inclusion of the blocking mode is also provided on the lower gears too. The motion with blocking is the most economical mode of the "automatic" box. And when loading the load on the drive wheels, the lock is automatically turned off.

During the operation of the hydrotransformer, there is a significant heating of the working fluid, which is why the automatic box design provides a cooling system with a radiator, which is either embedded in the engine radiator, or is installed separately.

Any modern box "Automatic" has the following mandatory provisions on the cockpit-selector:

• P - Parking, or Parking Lock: Blocking leading wheels (does not interact with the parking brake). Similarly, as on the "mechanics", the car leaves "at speed" when setting for parking;
• R is a reverse, reverse transmission (it has always been forbidden to be activated at the time of the vehicle movement, and then in the design there were appropriate blocking);
• N - neutral mode, mode neutral transmission (activated with a short parking lot or towed);

• D - Drive, movement in front of the front (in this mode, the entire transmission row of the box will be involved, sometimes two higher transmissions are cut off).

And may also have some additional, auxiliary or extended modes. In particular:

• L - "Redeyaka", activation of the reduced transmission mode (small stroke) in order to move in complex roads or in off-road conditions;
• O / D - Overdrive. Saving mode and measured movement (with any possibility, the "automatic" switches to the top);
• D3 (O / D OFF) - the deactivation of the highest level for the active ride. Involved in braking by a power unit;
• S - transfers are spinning to maximum revolutions. It may be possible to manually control the box.
• A special button may be present at the automatic transmission to a higher transmission during overtaking.

Advantages and disadvantages boxes "automaton"

As already noted, weighing advantages Automatic transmissions, compared with mechanical, are: simplicity and comfort of controlling the driver for the driver: the clutch is not necessary to squeeze, "work" the gear lever is also. This is especially true on trips around the city, which make up, ultimately, the lion's share of the car run.

Transmission on the "Automat" are obtained more smooth and uniform, which contributes to the protection of the engine and the leading vendors of the car from overloads. Consumables (for example, a clutch or cable disc) are absent, therefore, it is more complicated in this sense. In general, the resource of many modern automatic transmission exceeds the resource of mechanical gearboxes.

The disadvantages of automatic transmissions are more expensive and complicated than that of the MCPP, the design; The complexity of repair and its high cost, Lower efficiency, worse dynamics and elevated, compared to the manual transmission, fuel consumption. Although, the improved electronics of the "automata" of the XXI century copes with right choices torque is no longer worse than an experienced driver. Modern automatic transmission gearboxes are often equipped with additional modes that allow you to adapt to a certain style of driving - a calm up to "frisky".

A serious disadvantage of automatic gearboxes are the impossibility of the most accurate and safe gear shift in extreme conditions - for example, on complex overtaking; On the road from a snowdrift or serious mud to quickly switching the rear and first gear ("in a split"), if you need to start the engine "from the Tolkach". It must be recognized that the automatic transmission is ideal, mainly for ordinary trips without freelance situations. First of all, in city roads. The "automata" and for "sports driving" are not very adapted (the dynamics of overclocking is slightly behind the "mechanics" in a bundle with a "advanced" driver ", and for a rally on a bomadroziness (it does not always be perfectly adapted to change the conditions of movement).

As for the fuel consumption, the automatic box can in any case be more than that of mechanical. However, if earlier this indicator was 10-15%, then modern cars It fell to at least significant marks.

In general, the use of electronics has significantly expanded the possibilities of automatic gearboxes. They received various additional modes of operation: such as - economical, sports, winter.

A sharp increase in the prevalence of boxes "automata" was caused by the appearance of the AutoStick mode, which allows the driver, if desired, choose independently the necessary transfer. Each manufacturer has given such a type of automatic transmission of its name: "Audi" - "Tiptronic", "BMW" - "Steptronic", and the like.

Due to advanced electronics in modern automatic transmission, the possibility of "self-improvement" has become available and the possibility of "self-improvement". That is, changes in the switching algorithm, depending on the specific style of driving the "host". Electronics provided advanced capabilities as well for self-diagnosis of automatic transmission. And we are not only about memorizing fault codes. The management program, controlling the wear of friction discs, oil temperature, promptly makes the necessary adjustments to the operation of the automatic transmission.

Automatic gearbox is part of a transmission capable of adjusting the torque and vehicle speed. This means that you no longer need to count the moment when clamping the clutch and let it go, as well as switch the speeds manually.

In this article, consider the principles of the mechanism.

History of creating an automatic transmission

Transmission automation historically occurred in three stages. The first attempt to make a car more independent undertaken Henry Ford at the beginning of the twentieth century. Ford T had a planetary KP, which demanded less skills from motorists to switch speed than an ordinary mechanical.

At the next stage, cars with semi-automatic transmission were enrolled in production. In them, automation is directed either to independent shifting gear, or to refuse to use the clutch, which significantly facilitated driving a vehicle.

Did you know? Such a semi-automatic transmission is still used on scooters.

The last step towards the transmission to the automatic transmission was the system proposed by the developers of the American company General Motors. It was based on the planetary model, which was previously used at the Ford factory, as well as hydraulics, which herself was included at the time when it is necessary to change the transmission. Both principles underlie the modern automatic transmission.

Device of nodes and mechanisms

The automatic transmission conditionally consists of three main parts:

1. Mechanical. Its responsibilities include changing the vehicle speed, as well as direct speed switching.
2. Hydraulic. This part of the automatic transmission transfers the torque between component parts KP without any driver actions.
3. Electronic. This component is the brain of the gearbox, which monitors the operation of mechanical and hydraulic systems, and also transmits signals to other vehicles of the car.

Components of automatic KP:

Did you know? In the USSR, the first hydrotransformators began to be used on cars such as "seagull", "Volga", ZIL, as well as some other vehicles.

Principle of operation

Any automatic transmission is based on a planetary gearbox, which consists of a sun gear and united by the drive and the crown gear. These nodes as much as the vehicle has a car.

Principle of operation:

1. All pulses on the gearbox come with two inputs connected to the crown and solar gears, and are transmitted through one output, which is provided by rotation drove.
2. When the pulse arrives at the entrance to the sun gear, they begin to rotate, which leads to rotation drove.
3. She drove, in turn, makes moving the crown gear, which entails a constant increase in the speed of rotation drove at the exit.
4. If the driver needs to go to rear goThe sun gears will start moving in the opposite direction.

Did you know? Per last year In Europe, 80% of all purchased cars operate on the automatic box. On the territory of the CIS countries, the purchase of cars with automatic transmission is only 10% of the total number of vehicles sold.

It is these discs that transmit power. Friction discs at the input of smaller diameter than at the output. This is explained by increasing the power of rotation during the transfer of the pulse from the entrance to the exit.

Pros and cons

Let's look at what pluses and minuses can be encountered when using a car with an automatic transmission.

Pros:

• convenience.No longer need to be distracted by switching speeds and use of clutch. The driver can be completely concentrated on the road;
• it is easier to move from the scene. Responsible for this process in the automatic transmission is electronics, and not the correct pressing of the clutch or gas pedal;
• car nodes have a longer service life due to electronics control. Very often, drivers, especially newcomers, do not switch the speed in time, which leads to a violation of the engine operation, or delay the adhesion, or work at all without it, which leads to its bravery.

• cars with automatic transmission have a high cost. Moreover, they are also more expensive in service than vehicles on the mechanical box gears;
• there are difficulties in bad weather. The main way to go out of drift or dirt is "Running", which is impossible when using the automatic box.

Important! During the switching speeds using a selector, it is impossible to put pressure on the gas pedal.

A car with a box machine is designed for people who value comfort. To determine which type of transmission is needed to you, should be practiced in driving and with mechanical, and with an automatic transmission.

The principle of operation of the automatic transmission: video

The automatic transmission is a device that allows you to independently, that is, without direct participation of the driver, choose one or another transmission to move. We will try to tell everything about automatic transmission, ranging from the history of development, ending with how to use the automatic transmission.

How did the machine gun appeared

A modern automatic transmission appeared due to three directions in the mechanics that were developed independently of each other and in the consequence became a single node that allows you to enable transmissions automatically, depending on the speed of the vehicle.

The first development in this direction was the emergence of a planetary transmission, which became the main mechanism car Ford. T. At first at the beginning of the 20th century. The essence of this device was to ensure that the transmissions are turned on smoothly with two pedals. One of them worked for an increase and decrease in gears, and the other activated the rear transmission. In those days it was a really novelty, because then in the transmissions of cars, synchronizers still did not apply that ensure the smoothness of the inclusion.

The second direction was the appearance in the 1930s of the last century the first semi-automatic gearbox when planetary mechanism It began to control the hydromefta. At the same time, the use of clutch in the car has not been canceled. This invention belongs to the well-known company General Motors.

Well, the last invention, it became application Hydromefta In this type of transmission, which reduced the appearance of jerks. In addition, this time, in addition to 2-steps, an overdrive was introduced for the first time - an increase in the transmission, while the gear ratio did not exceed the unit.

Chrysler, who in the 1930s introduced this innovation, presented a new type of transmission as a semi-automatic, although it is currently considered mechanical.

Ultimately, the automatic transmission, in the form she used to see, appeared in the 1940s and its creator became the company General Motors. In the same period, the company abandoned the use of hydromefta and began to use a special torque converter, which eliminated the possibility of slipping the element. Later, the standard was introduced, which implied five positions of the selector to the automatic transmission: "D", "L", "N", "R" and "P".

Device and principle of operation of automatic transmission

The design of the automatic box includes the following items:

1. Hydrotransformer - Plays the role of clutch and ensures the smoothness of the operation of the mechanism. The main function of the hydrotransformer is considered to be a smooth transmission of torque from the flywheel to the automatic transmission.
2. Planetary type gearboxes - Sequential torque transmission.
3. Clutches of friction type. In a different way, they are called "packages". Provide gear shift. Provide communication between gear mechanisms and tear it.
4. Overtaking coupling. Plays the role of the synchronizer and reduces the load arising from contacting "packages". In addition, in some designs, the automatic transmission is eliminated by braking by the engine, leaving in the work of increased transmission.
5. Shafts and drums To connect all parts of the box.

Regardless of the design of the automatic transmission, the transmissions switch over the same principle. All switching is carried out by moving the oil inside the automatic transmission, by incorporating those or other spools. Control of spools can be of two types: electrical or hydraulic.

Hydraulic drive uses oil pressure generated using a centrifugal regulator, which is connected to the gearbox. In addition, the pressure is created at the moment when the driver presses the gas pedal. Thus, the automation receives information about the position of the accelerator and performs the necessary switching of spools.

In electrical drive, solenoids are used, which are installed in spools and are connected to the automatic transmission unit. In most cases, this unit has a close relationship with. It turns out that switching gear will be carried out depending on the position. throttle valve, Gas pedals, vehicle speed and many other parameters.

How to use the automatic transmission + video

Without a doubt, the automatic transmission provides convenience of driving, although many drivers still prefer the mechanical box, feeling the car and completely controlling the transmission. Despite this, there is still a big percentage of those who really love ACP.

If you just plan to master the new kind Transmission, then it is necessary to take into account several nuances that will protect you from the premature breakdown of the node, because the planetary transmissions are very sensitive to mechanical overloads.

There are several positions of the selector:

• "N" - neutral gearbut. It does not need comment, this is the same as in an ordinary manual box.
• "P" - "Parking". This position allows you to block drive wheels and eliminate the possibility of a car's skate when parking.
• « D "- used to move the car forward. In fact, is the main position of the selector, which is responsible for all automatic switching.
• "L" - lower transmission. Is an analogue of the first transmission mechanical gearbox. It is intended to overcome the portions of the road where the movement at high speed is unacceptable.
• « R »- reverse gear . Used to move the car back.

Having understood with the position of the selector, it is time to learn how to use them correctly. First of all, the launch of the motor is assumed under the positions "P" or "N" and with a completely squeezed brake pedal. To switch to the "D" position, you must, not releasing the brakes, remove the leg from the gas and click on the button lock the selector, translate it and start moving.

At the same time, it should be borne in mind that with any change of the position of the selector, in no case cannot be pressed on the gas pedal.

Several important points:

For automatic transmission, it is unacceptable for the "Rash" method when overcoming the snow barrier. This is due to the fact that to translate the selector from the position "D" in "R" must be completely stopped the car. Otherwise, you can simply bring the entire transmission mechanism.

1. You can only move in winter on good winter rubber With a fairly large pattern of tread. At the same time, you need to establish a selector to the position "W" or "1", "2", "3". This is due to the fact that when the wheels hit the ice, the automation "thinks" that the car is not loaded and accelerates, which naturally leads to switching transmission. Thus, it turns out a sharp drift of the car.
2. and recommended only on the tow truck or method of partial loading of drive wheels. The fact is that the oil pump of the box is driven by MOC, and when it is turned off, the oil supply is turned off, which corresponds to the wear of the box mechanisms. Nevertheless, the developer has taken into account this factor, leaving several tug rules. For example, the speed should not exceed 40 km / h (although exceptions are also possible), the box must be filled with oil not as usual, but to the throat itself and the maximum towing distance should not exceed 30 km. At the same time, it is necessary to stop and give time a cooling mechanism, since it overheats very much at these moments. Many models with automatic transmission can not be towed, for example, all-wheel drive. Although you can disconnect the cardan and immerse the front wheels.
3. Automatic transmission not for extreme driving And in no case will not fail to fulfill such tricks as pressing gas and brake pedals at the same time. All this will lead to overheating and the subsequent breakdown of the node.

That's all you need to know about the automatic transmission.