What is DSG 7. What is DSG gearbox? We analyze the issue in detail

Many modern cars are equipped with a DSG gearbox. It is installed on passenger cars B and C class. It can also be found in cars of class D and above (a six-speed type of product is installed on powerful cars). Therefore, car owners want to know what a DSG transmission is and how it differs from its mechanical and automatic predecessors.

The DSG gearbox is a robotic equipment equipped with two clutches and two rows of gears associated with them. This modern device is available in six-speed and seven-speed versions.

DSG Structure

• double clutch;
• main gear;
• two rows of gears;
• differential;
• dual mass flywheel;
• control system.

How the DSG works

This gearbox sequentially includes gears of two rows. That is, when one of the gears is working, the next one is always selected, which means it is ready for use. This scheme of operation ensures switching without breaking the power flow. This greatly enhances the capabilities of the box, compared to its mechanical and automatic counterparts. After all, an engine with such a gearbox does not idle, fuel is consumed much more slowly, and the car receives improved acceleration characteristics.

The device of six-speed and seven-speed DSG

Dual clutch is necessary to transfer torque to two rows of gears. The seven-speed equipment contains two friction clutches. In the six-speed version of the box, the clutch is complemented by a drive plate connected to the flywheel and two friction clutches connected to the gear rows through the main hub. In addition, the seven-speed and six-speed DSG models differ from each other in the type of clutch. The seven-speed uses a dry-type clutch, supplemented by an electric pump. This design of the box allows you to reduce oil consumption and increase engine efficiency. The six-speed DSG uses a wet clutch. It needs a lot of oil, but this principle of operation can significantly increase the life of the equipment.

Each row of gears in the box is a primary and secondary rows equipped with gear blocks. During their operation, the second row controls even gears, and the first row controls odd and reverse gears. The primary shaft in the second row is a hollow device, put on a similar shaft in the first row. In this case, both input shafts are placed coaxially.

The gears of the primary and secondary shafts also have a different principle of operation. Those of them that are on the primary shafts are rigidly connected to the shaft itself. In contrast, the gears on the secondary shafts rotate freely, and between them there are synchronizers that include the desired gear. In addition, the DSG gearbox is equipped with a reverse gear on the countershaft. This device is necessary for reverse movement. The secondary shafts also contain the drive gears responsible for the final drive.

Gear shifting and clutch control is controlled by an advanced control system. It consists of:

1. An electro-hydraulic unit responsible for the operation of the hydraulic control circuit. This block consists of solenoid valves, multiplexer, control spools and pressure control valves. Solenoid valves are designed for gear shifting. The valve spools are controlled by a special selector lever. Pressure control valves are required for the operation of friction clutches. And the multiplexer controls the gearshift cylinders (8 cylinders in total), using electromagnetic valves for this. Part of the hydraulic cylinders works in the initial position of the multiplexer, and the other part - in its working position. During this process, the same solenoid valves are used.
2. An electronic control unit that ensures the operation of the system according to the signals from the sensors.
3. Input sensors that control the speed at the output and input of the DSG. Sensors also monitor oil temperature and pressure, and the location of the gear shift forks.

Video about DSG

Pros and cons of DSG

Based on the characteristics discussed above, the pros and cons of the DSG gearbox can be distinguished.

Its advantages include:

• no loss of engine power and its efficiency;
• increased acceleration speed;
• fuel balance (a car equipped with DSG consumes fuel 10% more efficiently than a car with a manual or simple automatic transmission);
• the function of shifting gears in manual and automatic modes (this possibility is not even available in every automatic gearbox).

Among the disadvantages of this gearbox should be highlighted:

• the high cost of the car (compared to cars equipped with conventional gearboxes);
• the complexity of the design, which is badly reflected in the repair of the gearbox (in case of serious breakdowns, you will have to pay a large amount of money for a new gearbox, since the old one cannot be repaired);
• negative impact on the control system of frequent temperature changes (such changes cannot be avoided when using DSG, so the gearbox fails faster than mechanical or automatic);
• the impossibility of repairing the control system and the need for new expenses for its replacement;
• excessive preselector overheating.

These benefits have made the DSG the most popular transmission in recent years. Therefore, many cars were equipped with it. For example, Audi Q5 and R8, SEAT Ibiza, León and Altea, Škoda Yeti and Octavia, Volkswagen Passat CC, Tiguan and Caddy, as well as many other cars from world famous manufacturers.

It is also worth highlighting the shortcomings inherent only in six-speed or only seven-speed gearboxes. For example, a seven-speed DSG fails faster than a six-speed. This is due to the peculiarities of the operation of the dry type clutch. In addition, in cars equipped with a seven-speed gearbox, jerking may be observed during the transition from first gear to second. However, this drawback is not common to all DSGs and is very rare.

Despite all the shortcomings, the DSG is much more convenient than any of its predecessors. It makes driving easier and improves its performance. Therefore, feel free to buy a car with this gearbox and do not think about possible problems. With such a modern device, you can determine your driving style and fix it with a selector. By doing this, you will save yourself from further contact with the transmission. But do not forget to control the correctness of its operation and immediately contact the car service if you detect twitches, noises and other signs of equipment failure.

Find out what kind of DSG gearbox it is, its advantages and disadvantages, the scheme and principle of operation. What cars are equipped with DSG. Description of the ECT system. Video.

DSG (full name "Direct Shift Gearbox" - direct shift gearbox) is a mechanical 6 or 7-speed gearbox. She has an automatic drive to select gears and two clutches. The peculiarity of such a box is that its connection to the motor occurs through two clutches. They are aligned.

The principle of operation of the DSG gearbox

In this case, the following gears function through one clutch: reverse and odd. Through another clutch - even ones work. Thanks to this device, a smooth transition is made between the steps. This is similar to the synchronous operation of the clutches of the nearby gears operating in mechanical "automatic machines".

While acceleration is still taking place in first gear, the second stage gear is already engaged, despite the fact that it is still spinning idle. The computer determines the moment of switching. At this point, the DSG hydraulic lines simultaneously release the first clutch and completely close the second. The torque that comes from the engine is transferred from first gear to second. The process continues in the same way until the last sixth step. After that, the opposite happens. When the sixth gear is engaged, the fifth gear begins to rotate simultaneously with it.

Video about the principle of operation:

Scheme "DSG"

1. Flywheel dual-mass;
2. Friction clutch No. 1;
3. Friction clutch No. 2;
4. Main gear driven gear;
5. Driven gear of the second stage;
6. Primary shaft of the second row;
7. 4th gear driven gear;
8. 3rd gear driven gear;
9. Driven gear of the first gear;
10. Secondary shaft No. 1;
11. Oil pump shaft;
12. Oil pump;
13. Secondary shaft No. 2;
14. 5th speed driven gear;
15. Driven gear of the sixth gear;
16. reverse gear axle;
17. reverse gear;
18. Primary shaft of the first row;
19. Double clutch;

Advantages of DSG

In the event of a drop in engine speed, consider how the DSG box is used. The result is a permanent connection between the engine and the transmission, while the gears are shifted without interrupting the power flow. This device needs only 8 milliseconds to complete the speed change.

The advantages of this box are also in the reduction of acceleration time and fuel economy. And this is important today. More importantly, when operating the DSG, shifts are not noticed and the illusion arises that the ride is constantly in one gear. There are only two pedals in the cabin - brake, gas. This is enough. The transmission selector is the same as for automatic transmissions. If you suddenly don’t like it, then there is always the opportunity to use the manual mode, in which the gearbox lever is moved up or down.

Disadvantages of DSG (its problems):

• The cost of a car with this PP system increases significantly due to the technical complexity of the equipment itself.
• According to the reviews of some car owners, small jerks of the car can be noted when picking up speed and when shifting gears.
• There are slight delays during hard acceleration - the gearbox does not have time to immediately jump over the gear. For example: You are driving in 4th gear and suddenly decided to pick up speed sharply, respectively, the box needs to jump through the fifth to the sixth gear, but it is already set for a smooth transition to the 5th gear, as a result there is a delay.
• Control units (mechatronics) wear out quickly and require premature repair.

What is "ECT"?

There is an innovation in the latest models of automatic transmissions. They are equipped with ECT (an electronic system with which you can control gear shifting). This system makes it possible to smoothly shift gears along with taking into account the speed of the machine, engine temperature and throttle opening.

Thanks to this, the life of the engine, as well as the transmission, is significantly increased. Depending on the taste of the car owner, you can choose different switching schemes: sports, economical or winter. For example, when using the sport mode, each gear is engaged a little later. As a result, the development of high engine power and its faster acceleration is possible. This is convenient when you need to merge into a stream of cars that is moving fast. However, this also increases fuel consumption. Therefore, the final choice always remains with the driver.

To date, the DSG gearbox with 6 feet (DQ250 - wet clutch) is actively used on cars of the brand:

• Volkswagen (Golf, Passat, Sharan, Eos, Touran, Beetle Beetle, Bora, Tiguan);
• Audi (A3, Q3, TT);
• Skoda (Superb, Octavia);
• Seat (Toledo, Alhambra).

Used on machines whose engine has a torque of up to 350 NM.

7-speed DSG gearbox (DQ200 - dry clutch "without lubrication"):

• Volkswagen (Golf, Passat, Sharan, Transporter, Caddy, Jetta, Touran, Beetle Beetle, Bora, Tiguan);
• Audi (A3, Q3, TT);
• Skoda (Fabia, Superb, Octavia);
• Seat (Ibiza, Leon, Altea).

Manufacturers install it only on cars with an engine torque up to 250 NM.

DSG for cars with a longitudinal engine is equipped with a 7-speed gearbox, - only in Audi cars (A4, A5, A6 A7 and Q5) with 4-wheel drive (full). Its factory name is DL501. It can deliver torque up to 600 Nm.

Video: "By hook or by crook", how DSG works

Engineering thought does not stand still, and automotive equipment developers strive to offer their customers new solutions that should make life easier for the motorist. One such invention was the DSG transmission. Translated from the original language, the decoding of the name sounds like this: to “box of direct gear shifting”.

The DSG box is the result of combining a manual gearbox and an automatic gearbox. The principle of operation of this type of gearbox is the presence of robotic equipment that automatically changes gears after the driver moves the lever to select a gear.

DSG automatic transmission, currently, is found in two versions: six- and seven-speed. The six-speed DSG entered production in 2003 and has reduced the acceleration time of cars, combining this function with fuel economy. DSG (seven) is a seven-speed version of the automatic transmission that is becoming more common and is often used in sports cars that require fast acceleration and smooth gear changes.

Let's see what a DSG box is and how it works compared to conventional automatic and manual gearboxes.

Description of the principle of operation of the checkpoint

This automatic transmission has two clutches, ensuring that there is no loss of power when shifting. This is because at the moment of switching one of the clutches is switched off and the second one is immediately switched on, which before that was in full readiness. Thus, it can be noted that the DSG system includes, in fact, two equal boxes, one of which is responsible for even gears, and the second for odd ones.

While driving, both of them are in working condition, but at each moment the clutch of only one box is closed, and when switching it opens, closing the clutch on the other. The box is considered robotic, because the gear shift is controlled by an electronic unit - Mechatronics. This is such an electronic device, the work of which is to timely close / open the clutches. The robot monitors the information that comes from all sensors: controlling the speed, monitoring the heating and the amount of oil, noting the position of the gear forks.

In general, it is believed that the DSG gearbox is a functionally more advanced manual gearbox. Technically, it is, and the main improvement is just the robot, which makes switching fast and uninterrupted. In models produced from 2015 to 2017, Mechatronic has received additional features that help to avoid breakdowns and increase the service life.

How DSG 7 works and how it differs from previous samples

The main difference between seven- and six-speed gearboxes is their principle of operation. If the DSG (six) uses the "wet" principle, in which the mechanical parts immersed in oil are constantly cooled, then in the DSG 7 the dry clutch does not overheat due to reduced torque. In this case, oil is saved, since it is used only for lubricating the discs.

Due to these differences, the two types of robotic boxes also have slightly different applications. Wet gearboxes are more common on a more powerful car, such as the Skoda Octavia, for example, and on a car for which torque is not very important, a dry gearbox is more often installed.

Benefits of a DSG gearbox

The positive aspects of the operation of the DSG box include the following:

• the fastest gear shifting;
• fuel economy due to the absence of power loss when switching from one gear to another;
• an increase in acceleration speed that is impossible in a car on which standard manual or automatic gearboxes are installed;
• the possibility of manual control of gear shifting.

All these positive features have made DSG boxes optimally suited to the development of the modern automotive industry. For example, SKODA has been using these transmissions for various Skoda Octavia models for several years now. So, by the end of 2014, Skoda managed to produce more than half a million DSG boxes.

But, despite the recognition among manufacturers, motorists continue to argue whether the DSG 6 robotic gearbox or its seventh version is really better than the usual automatic transmissions.

Disadvantages of using DSG in a car

Among those who have already bought a car with a DSG 7 gearbox, there are not only its fans, but also people who managed to test it in action and found some disadvantages of such an innovation:

• the complexity of the design of the new gearbox also increases the cost of the car on which it is installed;
• temperature fluctuations often occur, which reduce the life of the transmission;
• despite the large number of services, some serious breakdowns simply cannot be eliminated without completely replacing the gearbox. The same applies to cases when the robot is out of order - it simply cannot be repaired.

In addition, many motorists claim that the resource of this gearbox is much less than that indicated by the manufacturer.

Summarizing all of the above, I would like to once again remind motorists of the need for a thorough check of all systems upon purchase. Having decided to buy a modern car, you need to think about what reserves its maintenance will require.

Robotic boxes burst into the auto world as quickly as they once were automatic. For the first time in mass production and implementation for customers, these boxes were launched by the Volkswagen concern. This article will tell you what a DSG box is, how it works, how it differs from an automatic, the pros and cons, and what car manufacturers say about it.

What is a DSG box?

DSG is a second-generation robot gearbox that shifts gears using two clutches and electronics, with the participation of the driver. Today it is considered the best checkpoint and the most reliable. It shifts gears without breaking power and has the best dynamic qualities. The DSG also saves fuel because the internal combustion engine does not idle.

DSG comes in six or seven steps. The first is installed on more powerful cars, since it has more torque. The seven-stage robot is installed on less powerful cars, as well as on some trucks and buses.

Short story

For the first time, the DSG box was developed by Borg Warner. They wanted to create the perfect gearbox that would combine all the qualities of a manual transmission, automatic and CVT, and at the same time had no drawbacks. The shortcomings of the mechanics are known to everyone, the machine has power consumption, and the variator has a narrow range of operation. The robot had to absorb all these shortcomings, plus reduce the cost of maintenance and repair.

But things didn't go the way they wanted. It turned out that the six-speed box is not suitable for cars with low power. Then a seven-speed gearbox was additionally developed, which was suitable for such cars. But the excuses were not confirmed, because she was dry.

A year of work, testing, refinement and the new DSG has been introduced to some Volkswagen cars. Of course, there were some incidents, and the first batch was defective. But the factory quickly corrected everything and now the robot is widely used on many cars.

Principle of operation

The genius of the DSG box is that it combines two boxes in one box. It is equipped with two shafts, on one - even gears, on the second - odd. Two clutches, on each shaft, allow the most efficient gear shifting without loss of power and brief braking, as in an automatic transmission.

DSG clutch in six steps - the robot has a "wet" type (always in oil). This is done so that the discs are cooled and lubrication is constantly present. This function has significantly increased the resource of the checkpoint and it is about 300 thousand km. With careful use, you can stretch up to 450,000 km.

The DSG-7, or seven-speed robot, is equipped with a dry clutch. This was done to reduce maintenance and service costs, but at the same time wear increased and resource decreased.

What is the difference between a robot and an automatic transmission?

When buying a car, any motorist thinks about which box is better to take? This often confuses the person. So what is the difference between a robot and an automaton?

The first difference is constructive. The robot is made so that the car does not lose power, and gear changes do not slow down the dynamics. The second is a technical difference: this is that the robot is mechanical in its structure and requires
participation of the driver in gear shifting.

Other differences between the machine and the robot:

• a robot is simpler than an automaton, since a robotic box is mechanical in nature;
• the robot has electronics that manages the switches;
• saving fuel by the robot;
• the ability to change the settings of the robot for a different type and driving style;
• manufacturability of the design for modernity;
• high reliability and quality of the robot.

Pros and cons of DSG

The advantages are:

• fuel economy (only in comparison with the machine, the savings on the variator are greater);
• instant gear change;
• no power loss;
• high resource;
• manual control.

DSG cons:

• high cost of repairs;
• expensive oil change cost (for DSG-6);
• does not tolerate aggressive driving style;
• the car is more expensive.

Proposals of manufacturers in robotic boxes

The manufacturer Volkswagen promises to refine the robotic boxes, as they are not yet perfect. The main problem that automakers face is the reduction in the cost of maintenance and repair. Leaving
advantages, it is necessary to make repairs and maintenance cheaper, since not every ordinary consumer can afford to service a car with such a cost of spare parts and materials.

According to many experts, these boxes are the future, although 40 years ago they were considered not promising and practically dead options. Now they are recruiting supporters and those who would like to have a car with a box
DSG, but can't afford it. But manufacturers promise to do everything in order to make the most available to the average consumer.

Conclusion

Having considered the DSG robotic gearbox, we can conclude that today this is the most ideal gearbox that combines all the advantages of mechanics and automatic transmission, while not being expensive to maintain 😉 like a variator. It has a sufficient number of advantages that modern drivers need.

This type of transmission belongs to the so-called preselective robotic gearboxes, the design feature of which is the use of two separate transmission units with shafts for even and odd gears, each shaft being controlled by its own clutch.

There are two types of such clutches - wet (using an oil bath) and dry (without using an oil bath), the second is considered more progressive. An important role in the design of such a transmission is played by the Mechatronic clutch control unit, which, using data on the speed of the crankshaft, the speed of the vehicle, the position of the gas pedal and the operating mode of the gearbox, determines the optimal moment for upshifting or downshifting. Then he gives a command to the hydraulics, which performs the gear shift. The main advantage of such a transmission is the sequential shifting of gears without a break in torque due to the fact that their shifting occurs beforehand: while, for example, the first gear is engaged, the second clutch is activated, and when the optimal torque for switching to an increased torque level is reached, the first clutch opens and then the second clutch closes. DSG gearboxes (“Direct Shift Gearbox”) are installed on Volkswagen cars, on models of other brands such transmissions are also used, but have different names - PDK, DCT, SST, S-Tronic and so on.

Let's get back to DSG. Currently, there are two types of this transmission - a six-speed wet clutch and a seven-speed dry clutch. Both transmissions have their pros and cons. Let's start with the merits. In addition to the smooth and fast (up to 8 ms) gear changes mentioned above, the advantage of this gearbox is its optimal combination with engines whose torque is less than 250 Nm. Another advantage is economy, which is achieved due to the fact that when changing gears there is no interruption in the flow of engine power, therefore, fuel is not wasted to restore engine power. It is possible to shift gears in both "automatic" and "mechanical" modes (the latter involves controlling the transmission as in conventional "mechanics").

Now about the disadvantages of the DSG box. First of all, this is the high cost of a car with such a transmission. The high price also affects the high cost of maintenance (transmission oil change) and repair of the dual clutch box. In Russia, as practice shows, it is almost impossible to repair such boxes, therefore dealers often resort to a complete replacement of the unit. Another disadvantage of this box (typical for a seven-speed gearbox, although it was previously noted on a six-speed DSG) is jerking when moving in first gear. Also, this transmission is characterized by rolling back when starting a car uphill.