Types of gearboxes. Robotic Mechanics: Harbingers of Skynet

07.04.2019

Modern manufacturers they install a variety of gearboxes on cars, and this is not only about automatic systems transmission. Even structurally simple ones are divided into various types and have features. let's consider existing species Photos and more - further in the article.

Mechanical transmission

Since the invention mechanical transmission more than a hundred years have passed. Over the years, designers and engineers have made a lot of changes to the gearbox mechanism, which made it possible to bring this mechanism almost to perfection, and now there are practically no serious flaws left in the mechanical box.

Mechanical transmission today is considered one of the simplest and most convenient, although there are more complex types of gearboxes. But you can call simple and convenient only the box where the number of steps is not more than 5 - this is the best option. Modern manufacturers produce manual transmissions with a large number of steps, for example, there are some types of manual transmissions with six steps. However, this does not affect the coefficient useful action modern engines.

Sequential manual transmissions

This transmission system, according to the device and principle of operation, also belongs to the mechanical ones. The idea is to use such a device on civilian vehicles came into the minds of motorsport engineers. Works this decision based on a traditional mechanical box, but the drive here is controlled by electronic systems. main feature, which distinguishes these types of gearboxes - they comply with basic principle switching and sequencing. This guarantees convenience and comfort in the process of driving - no matter how far you need to drive.

Among the advantages of sequential transmission, one can single out the possibility of choosing the optimal speed modes through fast switching, consistent switching actions without any harm to the motor on high revs. In addition, the way the driver controls the shifts is considered an advantage - there are special paddle shifters on the steering wheel that allow you to instantly select the desired gear at high speed. These gearboxes use gears with straight teeth, but the synchronizers that are in traditional mechanics are absent. The speed of rotation of the gears is aligned using a speed sensor in the control unit. These types of boxes are very popular with race car drivers because they reduce the turn-on time by 80%. desired gear. This makes driving comfortable for both beginners and professional drivers.

Robotic checkpoints

Robotic systems are types of transmissions that are neither mechanical nor can be compared with sequential transmissions, but in them electronics are responsible for switching, and in robotic solutions a special electromechanical drive is responsible for changing gears. These boxes have in common with mechanical ones that this design is based on a traditional manual transmission, but each shaft is equipped with its own clutch. The design feature that these types possess is the ability to calculate the transmission, which in this moment will be the most optimal in a particular mode. We can say about such transmissions that they are related to mechanical boxes. However, this is an intermediate link between mechanics and automatic transmission, both in terms of price and functionality.

Mechanical transmission structure

Exist different types. The gearbox of a car can be different in design and structure. All boxes existing in the world can be divided into two- and three-shaft. Each case has advantages and disadvantages.

Two-shaft manual transmission

The drive shaft on such a transmission system fully guarantees the connection with the clutch. The driven shaft is located in such a way that there is a block on it. Both provide different angular speeds of the differential. The switching mechanism can be provided with the help of rods or with the use of special cables. Cables are considered the simplest, most effective, and also reliable option. Some types of gearboxes (VAZ-2107, for example) are equipped with just this type of drive. It is also the most common drive.

The principle of operation of such a gearbox is very similar to the algorithm of a three-shaft gearbox. The main difference between them is in some features of gear shifting. When the gear is engaged, the lever splits both longitudinally and transversely. And the choice of the desired gear is provided with the help of all the elements and their interaction with each other.

Three-shaft manual transmissions

The design of the gearbox provides for the presence of a driving and driven shaft. They are equipped with synchronizers and gears, as well as a gear shift mechanism. With the help of the drive shaft, the mechanism is connected to the clutch. In addition to the drive shaft, there is also an intermediate one, which includes gears from the block. The shift mechanism is located in the gearbox housing. Its design consists of sliders with forks. In order to exclude the operation of two gears at the same time, mechanisms are used remote control. These boxes do not provide for the transmission of torque to the front wheels. When the driver moves the shift lever, the clutches move. With the help of it, the speeds are synchronized.

Types of automatic transmissions

Residents of megacities choose a machine.

The main argument for automatic transmission is convenience. And yes, in fact, with automatic transmission, the process of driving in traffic jams is greatly simplified. But what is hidden under the word “automatic” familiar to every motorist? Let's see what types of gearboxes modern manufacturers offer.

Torque converter automatic transmission

This is a classic among automatic transmissions. The mechanism is a mechanical gearbox and a torque converter. The process of transferring torque from the engine to the first is carried out using the second. The torque converter is a pump wheel, which is also driven by a motor. The wheel provides the transmission of torque to the oil, and it makes the element that rotates input shaft Checkpoint. With all the advantages, the torque converter has a very low efficiency. But this is outweighed by ease of control, smooth change in torque, as well as a significant reduction in stress on transmission parts.

Tiptronic

This is a hydromechanical box with the possibility of manual control. For the first time, these systems were installed in the 90s on Porsche cars, and later BMW, Audi, as well as other automakers became interested in tipronik. Interesting fact- the manufacturer is sure that this is not one of the species automatic transmission, but only the toggle type. In normal mode, this automatic transmission works in the same way as a traditional automatic. However, the driver has the ability to drive the car manually at any time, which is very convenient in some cases. For example, with the help of tiptronic, engine braking can be applied.

Among the advantages of these solutions are fuel consumption, which is lower than that of a traditional torque converter. The downside is that the tiptronic has large overall dimensions, and the switching speed is slow.

Multitronic

This system was developed by engineers from Audi. The design feature is that there are no steps in this checkpoint. But at the same time, the driver has the ability to manually shift gears. The principle of operation of this system is built on. As the main node, a variator is used here, which changes the torque. However, one cannot compare multitronic with modern stepless CVT variators- its design differs from stepless variator in the direction of complication and instead of a belt, special chains are used here.

Among the advantages are smooth acceleration, good dynamic performance and low consumption fuel. Indicators for dynamic characteristics are not inferior to cars with manual transmission. Minus - high prices, difficulties in repair and maintenance, a small resource.

Stepless variator, or CVT

By appearance these transmission systems are not much different from a traditional automatic transmission, but the principle of operation here is completely different. There aren't really any gears here, and nothing shifts here.

The gear ratios, and accordingly the torque, changes constantly, regardless of whether the car accelerates or slows down.

Summary

Modern Automotive industry does not stand still. Something new and more efficient is constantly being created. There are other types of gearboxes - unfortunately, it is simply impossible to tell about everything that is in the world.

Remember how one famous song sings: "Hold on tight to the steering wheel, driver!" At the time when the lyrics to this song were written, drivers had to hold on to the steering wheel with just one hand from time to time, wielding a manual transmission lever. Today, thanks to the “machine”, you can give the “steering wheel” all your attention, without being distracted by games with “mechanics”. Consider the main types of automatic transmissions.

It is unlikely that anyone will argue with the fact that the automatic transmission has dramatically reduced the workload of drivers, relieving them of the need to stomp the clutch pedal and giving them the opportunity to feel as comfortable even in the car as they do at home in front of the TV. And if you decide to give preference to a car with an automatic transmission, then you will find a rather difficult choice of transmission type. Yes, usually the end consumer does not pay attention to the checkpoint device, for him the main thing is two pedals, a selector and a road rapidly running under the car. However, take your time, because there are types of transmissions that are a better option.

Hydraulic "automatic": a classic in its purest form

This type of automatic transmission is a classic example of an automatic transmission, the peculiarity of which is that there is no connection at all between the wheels and the engine. You ask - how is the torque transmitted? We answer - through working fluid through two turbines. However, we evolve, and everything we invent evolves with us, because today such boxes are controlled by special electronic devices. This allows you to equip hydromechanical boxes gears with sports and winter modes, economical driving programs, as well as the possibility of manual gear shifting.

The automatic transmission was initially installed exclusively on top versions

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If we compare the "hydraulics" with the manual transmission, then the first one needs more fuel, as well as more time for acceleration. Well, you have to pay for comfort. But it was "hydraulics" that first challenged outdated mechanics and won a triumphant victory in many countries. But not in Europe. In the Old World, the automatic transmission could not take root for a long time. Perhaps the Europeans are so demanding, or the habits are almost ineradicable, but the engineers had to work hard to finalize the automatic transmission for Europe. But after that, the “automatic” learned to adapt to the driving style, which gave us as a result an economical, sporty and winter modes work.

Automatic transmission with tiptronic and sport mode

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Many drivers would be happy to use automatic transmission, but at the same time they did not want to give up the ability to change gears on their own. And the solution was found - the new "machines" began to be equipped with manual mode. Each manufacturer has its own name for this type of box, but the first was Autostick. To date, the most common name is the notion Audi- Tiptronic. BMW designers called such a box Steptronic, and Volvo decided that Geartronic would be quite suitable.

Despite the fact that when you turn on the manual mode, the driver himself changes gears, it still cannot be called fully manual. Rather, it is semi-automatic, because the transmission computer continues to work at this time and still controls the operation of the car.

Robotic Mechanics: Harbingers of Skynet

MTA (Manual Transmission Automatically Shifted), and in the common people simply a “robot”, by its design claims to bear the proud name of “mechanics”, but at the same time in terms of control it is pure water automatic transmission. At the same time, fuel consumption here is already significantly less than on the "mechanics". But not everything is so sweet. There is also its own bitterness: the "robot" is loyal only in relation to a quiet driving mode. As soon as you decide to step into the coal fire and press the gas pedal to the floor, you will immediately feel painfully how the gears are shifting. It feels like every time you change gear, someone pushes you into rear bumper. But this is more than offset by the low weight of the box and its relatively low cost.

Direct Shift gear box from Volkswagen

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“Robot” with two clutches: you won’t be fed up with one clutch

As we said above, the “robot” needed serious improvement, because its shortcomings significantly affected the ride comfort. And the designers decided to equip it with two clutches at once.

Volkswagen Golf R32

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IN mass production this transmission was launched in 2003 by Volkswagen who installed it on golf cars R32. This "robot" was given the name DSG (Direct Shift Gearbox). Two clutch discs controlled different programs- even and odd. This significantly softened the work of the box, however, this mechanism also has its drawback, which cannot be called insignificant - this is a high price. However, if the “robot” with two clutches wins the hearts of users, then this will cease to be a problem.

Variator: step rejection

CVT transmission (Continuously Variable Transmission) is different in that it can smoothly change the torque. This is a continuously variable automatic transmission in which the gears do not have a fixed gear ratio.

Variable speed drive Nissan Juke

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If we compare CVT with the classic "hydraulics", then in the case of the latter we can hear and also follow the operation of the box on the tachometer. But the CVT works very measuredly, maintains a balance of speed and constantly picks up the moment of gear change. This box will not appeal to drivers who like to "listen" to their car, because the variator constantly works in the same tone, like a trolleybus. However, you should not immediately abandon the variator due to acoustic monotony: the engineers came up with a way out of this situation and provided the box with a mode that allows you to manually select "virtual gears". This mode simulates a gear change and allows the driver to feel their shift, as when driving a conventional "automatic".

What does the coming day have in store for us?

What do experts say about who will own the championship laurels in the future? Most points independent "judges" put "robot" with two clutches, which is considered the most successful development at the moment.

It is unlikely that the variator will give up its positions, but here everything depends on the desire of car manufacturers to improve this species Automatic transmission, in which there are now more disadvantages than advantages.

The classic "automatic" is still grabbing its impressive piece of the pie, but its time is gradually running out. However, it is too early to tell him the terminator "Asta la vista".

Transmission type	Advantages	Flaws
*Hydraulic automatic transmission*	Can be installed on vehicles running on different types of fuel	More acceleration time and more fuel (average 1.2 liters) than a manual transmission
	Additional Modes provide smooth and comfortable movement
	Pretty stable at any speed
Robotic mechanics	Shifts quickly if transmission is idle	More expensive to manufacture than "mechanics" and hydraulic automatic transmission
	More economical than hydromechanics	Quite demanding in repair due to the complexity of the design
		On high speeds physically tangible gear changes
Variable speed drive	CVT picks up speed and drops it very smoothly	A small resource of the main assembly of the box (maximum - 200 thousand km)
	Such a box is more economical than a conventional "automatic"	Sophisticated electronic variator tuning system
	Engine efficiency quite high due to the lack of fixed "speeds"	Expensive transmission fluid, as well as shorter replacement times

Cars with a manual transmission, which is abbreviated as manual transmission, until recently made up the vast majority among other vehicles with different ones.

Moreover, a mechanical (manual) box remains a fairly common device for changing and transmitting engine torque today. Next, we will talk about how the "mechanics" is arranged and works, what the gearbox scheme of this type looks like, and also what advantages and disadvantages this solution has.

Read in this article

Manual transmission diagram and features

Let's start with the fact that this type of gearbox is called mechanical due to the fact that such a unit involves manual switching gears. In other words, on cars with manual transmission, the driver himself switches gears.

We go further. The "mechanics" box is stepped, that is, the torque changes in steps. Many motorists know that the gearbox actually has gears and shafts, but not everyone understands how the unit works.

So, a stage (it is also a transmission) is a pair of gears (driving and driven gear) interacting with each other. Each such stage provides rotation with one or another angular velocity, that is, it has its own gear ratio.

Under the gear ratio should be understood as the ratio of the number of teeth of the driven gear to the number of teeth on the drive gear. In this case, different stages of the box receive different gear ratios. The most low step (downshift) has the largest gear ratio, and the highest stage ( overdrive) has the smallest gear ratio.

It becomes clear that the number of steps is equal to the number of gears on a particular box (four-speed gearbox, five-speed, etc.) Note that the vast majority of cars today have five step box gears, manual transmissions of 6 or more steps are less common, and the previously quite common 4-speed manual gearboxes gradually faded into the background.

Manual transmission device

So, although there can be many designs of such a box with certain features, however, at the initial stage, two main types can be distinguished:

three-shaft gearboxes;
two-shaft boxes;

For vehicles with rear wheel drive usually installed three-shaft mechanical box gears, while the two-shaft gearbox is placed on front-wheel drive passenger cars. At the same time, the device of mechanical gearboxes of both the first and second types can differ markedly.

Let's start with a three-shaft mechanical box. This box contains:

the drive shaft, which is also called the primary;
intermediate shaft gearbox;
driven shaft (secondary);

Gears with synchronizers are installed on the shafts. The gearshift mechanism is also included in the gearbox. Specified constituent elements located in the gearbox housing, which is also called the gearbox housing.

The task of the drive shaft is to create a connection with the clutch. The drive shaft has slots for the clutch disc. As for the torque, the specified torque from the input shaft is transmitted through the gear, which is in rigid engagement with it.

Affecting the work of the intermediate shaft, this shaft is located parallel to the input shaft of the gearbox, a group of gears is installed on it, which is in rigid engagement. In turn, the driven shaft is mounted on the same axis as the drive shaft.

Such an installation is implemented using an end bearing on the drive shaft. This bearing includes the driven shaft. The group of gears (gear block) on the driven shaft does not have a rigid engagement with the shaft itself and therefore rotates freely on it. In this case, the group of gears of the intermediate shaft, the driven shaft and the gear of the drive shaft are in constant engagement.

Synchronizers (synchronizer couplings) are installed between the gears of the driven shaft. Their task is to align the angular velocities of the gears of the driven shaft with the angular velocity of the shaft itself through the force of friction.

Synchronizers are in rigid engagement with the driven shaft, and also have the ability to move along the shaft in the longitudinal direction due to the presence spline connection. Modern gearboxes have synchronizer clutches in all gears.

If we consider the gearshift mechanism on three-shaft gearboxes, often this mechanism is installed on the unit body. The design includes a control lever, sliders and forks.

The box body (crankcase) is made of aluminum or magnesium alloys, it is necessary for installing shafts with gears and mechanisms, as well as a number of other parts. There is also gear oil (gearbox oil) in the gearbox housing.

To understand how a three-shaft type mechanical (manual) gearbox works, let's in general terms Let's take a look at how it works. When the gear lever is in the neutral position, there is no transmission of torque from the engine to the vehicle's drive wheels.

After the driver moves the lever, the fork will move the synchronizer clutch of one or another gear. The synchronizer will then align angular velocities desired gear and driven shaft. Then the gear ring of the clutch will engage with a similar gear ring, which will ensure that the gear is locked on the driven shaft.

We also add that the reverse gear of the car is provided by the reverse gear of the gearbox. In this case, the intermediate gear reversing, installed on a separate axis, allows you to change the direction of rotation.

Two-shaft manual gearbox: device and principle of operation

Having dealt with what the three-shaft gearbox consists of, let's move on to two-shaft boxes. This type The gearbox has two shafts in its device: primary and secondary. The input shaft is the driving one, the secondary is the driven one. Gears and synchronizers are fixed on the shafts. Also in the crankcase of the box is the main gear and differential.

The drive shaft is responsible for connecting with the clutch, and there is also a gear block on the shaft in rigid engagement with the shaft. The driven shaft is located parallel to the drive shaft, while the gears of the driven shaft are in constant engagement with the gears of the drive shaft, and also rotate freely on the shaft itself.

Also, the drive gear is rigidly fixed on the driven shaft. main gear, and between the gears of the driven shaft there are synchronizer clutches. We add, in order to reduce the size of the gearbox, as well as increase the number of gears, in modern gearboxes, 2 or even 3 shafts can often be installed instead of one driven shaft.

On each such shaft, the gear of the main gear is rigidly fixed, while such a gear has a rigid engagement with the driven gear. It turns out that the design actually implements 3 main gears.

The main gear itself, as well as the differential in the gearbox device, transmit torque from secondary shaft on the drive wheels. In this case, the differential can also provide such rotation of the wheels when the drive wheels rotate at different angular speeds.

As for the gearshift mechanism, on two-shaft gearboxes it is taken out separately, that is, outside the body. The box is connected to the switching mechanism by cables or special rods. The most common connection is with cables.

The switching mechanism itself shaft box has a lever that is connected by cables to the selector lever and the gearshift lever. These levers are connected to the central shift rod, which also has forks.

If we talk about the principle of operation of a two-shaft manual gearbox, it is similar to the principle of a three-shaft gearbox. The differences are in how the gearshift mechanism works. In a nutshell, the lever can carry out both longitudinal and transverse movements relative to the axis of the car. During lateral movement, gear selection occurs as force is applied to the gear selection cable, which acts on the gear selector lever.

Further, the lever moves longitudinally, and the force goes to the gearshift cable. The corresponding lever horizontally moves the stem with the forks, the fork on the stem displaces the synchronizer, which leads to blocking of the driven shaft gear.

Finally, we note that also mechanical boxes different types have additional blocking devices that prevent the inclusion of two gears at the same time or an unexpected disengagement of the gear.

Types of gearboxes, main differences

Modern cars are equipped not only, in addition to mechanics, there are also:

Automatic boxes.
Robots.

All types of car gearboxes are characterized by both certain advantages and some disadvantages. Among buyers, various types of gearboxes are popular. The choice of type of gearbox depends on the following factors:

belonging of the buyer to a certain age category;
public status;
material possibilities of a person;
vehicle operating conditions, etc.

Manual transmissions

The mechanical gearbox is presented in the form of a multi-stage spur gearbox. The classic version is a 4-speed gearbox. Modern cars divided into types, depending on the number of steps: they are often equipped with 5- and even 6-speed gearboxes.

What does the concept of a stepped gearshift system mean? The moment of rotation is transferred from to undercarriage car not directly, but through the gearing of various pairs of gears. In this case, the value of the torque undergoes changes, in accordance with the ratio of the number of teeth on the driving and driven wheels ( gear ratio). Usually, driving wheel has a smaller diameter than the driven, so the torque decreases in proportion to the given gear ratio.

The gears of the forward and reverse gears differ in shape. For forward gears, helical gears of original outlines have been developed. This shape of the tooth makes it possible to transfer power gradually without loud grinding sounds. When turned on reverse gear wheels with straight teeth engage. The efficiency of the straight teeth is noticeably increased. At the same time, it is transmitted greater moment rotation, but at the same time there are such negative phenomena as noise effects.

Types of transmissions. Structurally, manual gearboxes divided into:

2-shaft.
3-shaft

Two-shaft types of gearboxes are designed for machines equipped with leading front-wheel drive. Three-shaft mounted on vehicles increased power(special equipment, trucks, tractors, all-terrain vehicles).

Among the types of boxes presented, there are also such gearboxes of cars as, where is the transition to next gear produced in a strict sequence.

In a manual gearbox, the speeds are switched manually using a special lever in the passenger compartment.

Types of automatic transmissions

Modern cars equipped with an automatic transmission are gaining more and more popularity among motorists. This is due to numerous, in comparison with traditional mechanics. Drivers appreciated the comfort of driving with installed automatic transmission and when buying a new car, many buyers prefer just such mechanisms.

While the car is moving, you do not have to be distracted from the road to change gear. Beginners quickly learn driving techniques, as there is no need to remember which position to set the gearshift lever to change modes. Everything is simple here: in order for the car to start moving, it is enough to move the selector to point “D” and turn off the brake.

The working element of the machine is planetary gear, which consists of a set of gears:

Main gear.
input gearbox.
Reverse gear.

With the help of gearing of the main gear, the torque is transmitted from the output shaft of the engine to the chassis of the vehicle.

In addition to gears, the automatic transmission includes:

synchronizing clutches;
gear lever - selector;
lubrication system.

Automatic gearbox speeds are switched due to complex control actions on-board computer. redistribute the direction of flows in the hydroblock. Transmission fluid under pressure is sent to the synchronizer clutch, the gear connection of the selected gear is put into operation.

Thanks to the automatic transmission, the vehicle's powertrain selects the most efficient power band. Based on information from numerous sensors, the computer controls the gears, depending on the conditions traffic and wishes of the driver.

In cars equipped with automatic transmission, there is no clutch mechanism and the usual pedal in the cabin. The transfer of power from the engine to the automatic transmission is carried out using. Compared to mechanical clutch, the automatic transmission torque converter allows you to align the speed of rotation of the engine output shaft with the gearbox more smoothly without noticeable jerks. During its operation, static and dynamic loads on the working elements of the transmission are significantly reduced.

Externally, the automatic transmission torque converter resembles the shape of a torus, for which it was colloquially given the name "donut".

The hydrotransformer includes:

Turbine wheel with blades.
Lockup clutch and freewheels.
Pump.
Reactor wheel.

All components of the device are located in a single housing, they work in an oil environment. The pump is directly connected to crankshaft motor. accelerated by the blades of the wheel and involves in the movement of the turbine, coupled with the gears of the gears of the gearbox.

Types of automatic boxes

Automatic transmissions differ from mechanics by the method of transmission from the engine crankshaft to the transmission. A distinctive feature of the automatic transmission is the absence of direct contact between the power unit and the gearbox elements. Torque and power are transmitted through the automatic transmission's torque converter turbines and transmission fluid. This design is called "hydraulic automatic transmission".

The control of the machine is carried out thanks to the operation of specialized electronic devices. modern box The machine received additional features:

winter mode;
sports;
economical driving mode;
gear shifting in both automatic and manual modes (tiptronic);
adaptation of control to the individual driving style of the operator.

Unlike mechanics, automatic hydraulic type consumes more fuel, the reason is the low efficiency of the torque converter. This is a kind of payment for comfort.

- one of the varieties of automatic boxes, in which, along with automation, it is possible for a person to participate in self-management modes. Automatic control classic automatic transmissions not always able to adjust the speed in the following cases:

When you need to add additional auto acceleration (upshifting).
Downshift on tight turns.
Braking with an engine, etc.

You cannot do without the human factor when you need to accurately install the automatic transmission selector in a special slot on the rocker mechanism.

At the same time, it is required to independently select the “+” or “-” sign. Only after the correct mode selection, the corresponding signal is sent to the ECU to further start the gear shifting algorithm. IN latest developments new models increasingly began to appear for these purposes, special "petals" - switches that are located under the steering column.

The list of types of automatic transmissions can be supplemented with the names Autostick, Steptronic, Geartronic. This is the same Tiptronic automatic transmission, which is represented by various automakers: AUDI, BMW, Volvo.

Important: Despite the fact that in this embodiment, partial speed control is shifted to a person, the gearbox is not mechanical. It's still an automatic, you can call it a semi-automatic, because, regardless of the manual method of switching the selector, comprehensive control over the operation of the car is carried out using computer programs.

Robot or robotic gearbox (RCP)

The robot box differs from the machine in its device and principle of operation. By design, robotic boxes are closer to mechanics. Only the clutch and gearshift control is carried out in automatic mode. For electronics, input data is required: road conditions and driver requirements. Modern vehicles, equipped , have double friction clutch. This allows minimizing power losses transmitted from power unit to a robotic transmission and further to the wheels of a car. To transmit torque, the principle of a parallel multi-plate clutch is used here instead of an automatic transmission torque converter.

The robot box is controlled using a special electronic system. The system includes:

gearbox (ECU).
Sensors for speed, temperature, oil pressure in the valve body and other important parameters.
executive mechanisms.

Preselective method of switching speeds

Unlike automatic transmission, in a robotic box, two gears are always on at the same time - one in even, the other in odd rows. When switching speeds, an instantaneous transition of the clutch from one to another gear pair occurs. In this case, the flow of transmitted power is practically not interrupted.

The big advantage of robots is their compact dimensions and relatively light weight. Two driven shafts of the gearbox with working gears of even and odd gears are located one inside the other. Thanks to this solution, the box occupies a minimum volume in the engine compartment.

Interesting: Robotic gearboxes are considered the most durable, reliable and economical mechanisms among all types of checkpoints. This is due to the increased strength of the mechanical part of the structure. Many car owners and mechanics note a reduced consumption of both fuel and transmission oil in cars equipped with a robot box.

Gearbox - variator

CVT gearboxes are stepless devices. Unlike the gearboxes described above, there are no usual shafts and gears. The design consists of the following working elements:

Two tapered pulleys that allow you to change the radius of coverage.
A metal belt (chain) consisting of a set of separate plates made of high-strength alloyed alloys.

The speed of the car changes smoothly, due to the degree of belt tension and the change in the ratio of the gear ratio between the movable pulley disks.

The disadvantages of the variator box include their use in cars of low power. The main application is scooters, small cars.

Design developments modern automotive industry do not stand still. Competing firms are constantly working on improving the released models and introducing new ones. fresh ideas. Every year you can hear about innovations with improved technical and operational characteristics.

Even before purchasing a car, the owner will definitely be faced with the question of which type of transmission to give preference to. There is no consensus on which gearbox is better. Do right choice, knowing what types of boxes exist, their advantages and disadvantages, operating features, possible breakdowns and other nuances.

Types of automotive gearboxes

1. Mechanical transmission (manual transmission). Purpose - serves to step change the torque and transfer it from the engine to the driving wheels of the car. Manual transmission classification by the number of steps:

Four-stage.
Five-speed boxes (widely used on domestic cars).
6-speed.
8-speed.

Device and principle of operation: when lever 2 is switched to one of the positions required by the driving conditions, the drive gear (red in the diagram) on the input shaft 1 from the engine engages with another gear (in the diagram blue color) mounted on the intermediate or driven shaft 6. To equalize the speeds of rotation of the shafts and protect the gear teeth from breakage at the moment of engagement, a special gear shift mechanism 3 and a synchronizer clutch are provided. The intermediate shaft through the gear (green in the diagram) transmits torque to the drive wheels using shaft 4. When the lever 2 is in neutral position, the input shaft 1 from the engine and the shaft to the drive wheels 4 are disconnected and no torque transmission occurs. The principle of switching on the reverse gear is the same, only in this case the driven shaft with the gear rotates in the opposite direction.

2. The box is a robot.

This is a manual transmission in which the operation of the clutch and gear changes is controlled by the electronic unit with sensors. This unit engages or disengages the clutch and the corresponding gears with the help of actuators made in the form of servomechanisms or hydraulic cylinders with solenoid valves.

The driver does not work the clutch and does not change gears, since these functions are performed by electronics for him, but during city trips, in traffic jams, when driving on steep climbs, it will need to switch to manual control.

3.Automatic transmission (automatic transmission).

The working medium through which torque is transmitted from the engine to the drive wheels through planetary gears, is oil. The box is controlled by means of spools that distribute and direct the flow of oil under pressure. See how the automatic transmission works (video):

4. CVT. Automatic transmissions are often called sequential, since they change gears sequentially. A variator is an automatic transmission in which the change in gear ratio and the transmission of torque to the wheels occur smoothly, steplessly, that is, without fixing the first, second and subsequent gears.

Types of automobile variators.

V-belt.

In a simplified form, such a variator consists of two pulleys of variable diameter in the form of two cones connected to each other by a steel tape of complex section. When accelerating or braking the car, the tape moves along the cone, while the gear ratio gradually increases or decreases, and the driving wheels of the car, respectively, rotate faster or slower.

Toroidal.

Such a variator performs its function as a constantly changing transmission, using discs and rollers. The driving disk is connected to the motor shaft, and the driven disk is connected to cardan shaft. Rollers located between the discs transfer power from one disc to another.

Hydrostatic.

The crankshaft of the engine drives a pump that drives oil under pressure to another pump connected to the driven disk of the variator and transmits rotation cardan shaft. The pumps have a variable volume, which allows you to change the gear ratio and the speed of rotation of the driven disk and the vehicle as a whole.

Advantages and disadvantages of various types of transmissions

1.Mechanical gearboxes. The advantages of the MPP include:

Manual cars are cheaper than those equipped with automatic transmissions.
Repair and Maintenance cheaper than other types of transmissions.
The possibility of full control over the car during acceleration, overtaking and other maneuvers due to full use engine power.
Fuel economy.

2.Robotic gearbox: pros and cons. Advantages:

Design reliability.
Fuel economy up to 30%.
The resource of the box is 40% more when compared with mechanics.
Possibility of manual control of the box.

Flaws:

The imperfection of the electronic program of the box leads to a deterioration in the dynamic properties of the machine, “thoughtfulness” (up to 2 seconds) when shifting gears. All this complicates the ability of the driver to adapt the car to his individual driving style.
Increased clutch wear in case of untimely transition to manual control. On steep climbs, the box overheats if you do not switch to manual mode in time.
Jerks during automatic gear shifting with the accelerator pedal fully sunk into the floor.

3. Pros and cons automatic box gears. Positive sides from the installation of an automatic transmission on a car:

Convenience and comfort. The lack of clutch and the ability to hold the steering wheel with two hands, without being distracted by the manipulation of gear changes, increases safety and performance - the driver is less tired. On ice, the car does not lose control, since an engine that does not have a clutch does not stall.
The transition through the steps during acceleration and deceleration is shorter in time than with the manual transmission and occurs without loss of power.
Since gear selection is automatic, there is no risk of overloading the engine.

Disadvantages of automatic transmission:

Increased fuel consumption.
Expensive maintenance and repairs.
It is impossible to assist other drivers in towing, as well as towing a car with automatic transmission. In the event of a car breakdown, only the help of a tow truck is needed.
If the battery is dead, then a car with an automatic transmission cannot be started from the pusher.

4. Variator: pros and cons. "Pros" of the variator:

An infinite number of variator gears provide maximum comfort mode operation of the engine, extending its motor resource and durability.
Fuel economy.

During smooth acceleration, when the speed of the car increases, and the tachometer shows a constant number of revolutions (5-6 thousand), fuel is saved. This is due design features variator.

The disadvantages of the variator include:

Expensive repairs and maintenance.

Replacing the belt and special transmission fluid(7 liters instead of 3 - 4 liters of standard oil for a conventional automatic transmission) is not cheap.

CVTs are still installed mainly on compact, low-power and medium-sized cars. There are exceptions - for example, the X-Tronic variator is installed on the heavy SUV Nissan MuranoV6 (234 hp).

Features of operation of various types of transmissions

IN winter time Before driving, it is advisable to warm up the oil in the automatic transmission. To do this, hold the car with the brake and switch successively several times all modes on the selector.
To avoid overheating of the automatic transmission, avoid transporting heavy trailers and loads. Towing more than 50 km may cause overheating and damage to the box. The recommended towing speed is not more than 40 km/h.
The reason for slipping the torque converter may be a lack of oil in the box. At excess oil, it can foam, which will lead to a breakdown of the automatic transmission.
When cornering and at the moment of overtaking, it must be remembered that the gearbox with a variator reacts to an increase in the number of revolutions with a delay. It is necessary to press the accelerator pedal a little earlier, before the start of the maneuver.
Towing a car with a CVT is carried out either by partial loading with the drive wheels hung out, or with the help of a tow truck.
In traffic jams, it is undesirable to move the selector to the "Neutral" position. This technique increases the wear of rubbing parts and reduces the resource of the variator. For robotic box, on the contrary, it is required to transfer it to the neutral position, since the clutch is engaged in the “D” position. At the same time, the basket wears out, release bearing and driven disk.

Outcome

Any type of transmission has advantages and disadvantages, but all gearboxes require maintenance and compliance with operating rules. If you regularly check the oil level and change it at the time recommended by the manufacturer, avoiding overheating and overloading, then the gearbox will last a long time and without problems.