The strength of automotive transmissions-AT hydraulic automatic transmission


There are hundreds of millions of people who have cars. There are so many people who drive. People who know cars are nowhere to be found.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 1)

How long is the wheelbase of the car? How long does it take to accelerate from 100 kilometers? These data are not understandable and understandable by car enthusiasts. Anyway, there will be no loss. However, can your own car coast in neutral and save fuel? This still needs to be understood, after all, the damage to the car caused by wrong operation is quite large.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 2)

Wrong driving is more harmful

First, thunder-AT turned out

Automatic transmission cars are everywhere in this era, among which electronically controlled hydraulic automatic transmissions are widely used. It can automatically select gears according to changes in engine load and vehicle speed, and change gears in a timely manner. Drivers only need to adjust the accelerator pedal/throttle to control the speed of the car. The left-foot clutch, right-foot accelerator+brake fast switching, and hand-shifting, this set of actions is only suitable for use in driving schools, once you get the driver's license, it will be useless.

Electronically controlled hydraulic automatic transmission-AT, he liberated us, let's be free~

Two, breeze and drizzle-AT's temperament

The girlfriends all said: "AT is a good guy. He is not short-tempered and has a lot of advantages. Sometimes he is too shameless to be narcissistic."

Advantages of automatic transmission

1. Eliminate the differences in driver shifting technology. Your skills are good, I am not bad for money, and I will balance you with banknotes. The automatic transmission automatically changes the gear position according to the driving conditions of the car, and the driving performance has little to do with the level of the driver's technical level, so it is especially suitable for the non-professional drivers of the public.

2. Extend the life of the engine drive train . Because of automatic gear shifting, the engine always works under suitable working conditions, which is similar to that of a well-maintained woman who is slow and old. One reason.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 3)

3. Better transmission ratio conversion performance. The change is fast and continuous and stable, which improves the ride comfort.

4. Reduce driver fatigue and improve driving safety. Drivers will no longer rush into a tiger-like operation and just concentrate on watching the road, which is natural and safe.

5. Automatic transmission reduces pollution. The combustion is sufficient, and the emission pollution is small. When the engine is idling and the engine is running at high speed, the concentration of carbon monoxide and hydrocarbons in the exhaust gas is high, but when the engine is working in the economic speed range, the content of pollutants in the exhaust gas is very small.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 4)

6. The automatic transmission improves the power and passability of the car.

7. Good starting and acceleration performance, driving at a low and stable speed.

However, everything is a double-edged sword, and there are good and bad sides.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 5)

Double-edged sword, just ask if you are afraid

Compared with the traditional manual transmission, the automatic transmission has a complicated structure and a higher cost. It is necessary to pay more money when buying a car , and the later repair and maintenance are also more troublesome. Bluntly put, is the mechanic also be more money .

Another point is that the transmission efficiency of the automatic transmission is not high, and there is no direct transmission from the manual transmission. Technicians and engineers talk about engine matching optimization, hydraulic torque converter locking function, increasing number of gears, improving technology and improving efficiency, etc., which are all lie. The final result is: automatic gear is better than manual gear. High fuel consumption.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 6)

Third, in-depth analysis-unveiling the red hijab of AT

Uncover the red hijab of AT and see what it looks like. Why is it so charming?

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 7)

The hydraulic automatic transmission AT is mainly composed of four parts: a hydraulic torque converter, a planetary gear transmission mechanism, a hydraulic control system, and an electronic control system.

(1) Hydraulic torque converter

The torque converter is installed between the engine and the transmission. It transmits power, just like an intermediary or matchmaker. Its function is to transmit the power of the engine to the planetary gear transmission mechanism, which is similar to the manual transmission clutch, but it is higher than the manual transmission clutch between AC. The hydraulic torque converter has a certain torque conversion function, and can also achieve stepless speed change within a certain range.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 8)

(2) Gear transmission mechanism

The gear transmission mechanism is generally composed of a planetary gear mechanism. The planetary gear mechanism is composed of 2 to 3 rows of planetary gears, which can provide different transmission ratios.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 9)

Planetary gear mechanism

(3) Hydraulic control system

The main task of the hydraulic control system is to provide the required oil pressure to the automatic transmission systems according to the changes in the engine load (throttle opening) and vehicle speed (vehicle speed sensor); switch the hydraulic pressure according to the position of the joystick and the driving state of the vehicle Channel, to achieve the control of the torque converter and gear transmission system; control the working state of the lock-up clutch in the torque converter.

(4) Electronic control system

The electronic control system is used in conjunction with the hydraulic control system. The electronic control system includes various sensors, electronic controllers and actuators. The sensor collects various signals, such as throttle position, vehicle speed, water temperature, etc., and converts them into electrical signals and sends them to the electronic control unit. The electronic control unit compares the data after processing with the set shift schedule and sends it to the solenoid valve Instructions to determine the correct timing and gear shift. It's a bit like the human brain, which is the control center.

Four, matters needing attention when interacting with AT

I have been with AT for a long time, and the relationship is still very good. We should also pay attention to some places and don't hurt it.

The first of the three chapters of the contract Do not drive in the N gear. Manual transmission cars can be put into neutral gear to save fuel, but automatic transmission ones cannot. When an automatic car is coasting in N gear, the engine is idling, the oil pump output is small, and all the parts on the output shaft are still running at high speed. The transmission will wear out quickly due to insufficient lubricating oil, and it will burn out in extreme cases.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 10)

The second of the third chapter of the law : low gear is a forced brake gear of the engine, such as L gear or 1-position gear is usually only used on muddy roads and on long slopes, and is not suitable for long-term use.

Article 3 of Chapter Three: Automatic transmission oil except Volkswagen's VW ATF is light yellow, and the rest is red. If the oil turns brown, is viscous and has a burnt smell, it means that the oil has been oxidized and must be replaced. ATF oil loves to be clean, it is not good to be dirty, so people don't want it.

The strength of automotive transmissions-AT hydraulic automatic transmission (Figure 11)

In general, the current automatic transmission models are already mainstream, and automatic transmissions are becoming more and more common. The original 4AT has been upgraded to 6AT/8AT or even 10AT. I wonder if the hydraulic automatic transmission will dominate the world in the future, or will it be eliminated by pure electric vehicles?