Do you know what an automatic transmission is?

The automatic transmission can be divided into two forward gears, three forward gears, and four forward gears according to the number of forward gears. Early automatic transmissions were usually 2 or 3 forward gears. Both automatic transmissions do not have overdrive, and their top gear is direct.

The automatic transmissions installed in the new cars are basically 4-9 forward gears, that is, overdrive. Although this design makes the construction of the automatic transmission more complicated, it greatly improves the fuel economy of the car due to the overdrive. Automatic transmissions can be divided into two types: fixed-shaft gear type and planetary gear type according to the different types of gear transmissions.

Fixed shaft gear automatic transmission is larger in size, smaller in maximum transmission ratio, and less used. Planetary gear automatic transmission has a compact structure and can obtain a large transmission ratio, which is adopted by most cars.

Automatic transmission has extremely strict requirements for oil, which requires oil not only to lubricate, clean and cool, but also to transmit torque and hydraulic pressure to control the working performance of clutch and brake, so automatic transmission oil is a special high-grade lubricating oil, commonly called"atf"There are many kinds of models, and the common ones in China are FORD standard F type and GM standard dexronii type, remember to recognize it when using. "atf"Depending on the model, the coefficient of friction is not the same. If the dexronii type is used instead of the F type, the automatic transmission will be subject to a shift shock and the brakes and clutch will suddenly engage.

If the F-type is misused for the dexronii type, it will cause the clutch and brake in the automatic transmission to slip, and accelerate the early wear of the friction pads.

The mode is different. There are two options for manual mode and automatic mode. The driver can choose between manual and automatic mode. The automatic transmission does not have a manual mode.

Practical techniques are different. The automatic manual transmission is a transmission device that combines manual and automatic transmission functions, and allows the driver to choose the timing of the shift in manual mode. However, ordinary automatic transmissions can only allow the computer to choose the timing of shifting, not the driver.

Yuhui. The structure is different. The automatic manual transmission is mainly composed of an ordinary gearbox, an electronically controlled clutch, an automatic shift control mechanism and an electronic control part. Whereas, a normal automatic transmission is a hydraulic automatic transmission.

Because manual transmission needs to change gears frequently according to road conditions during driving, the timing and handling process of gear shifting are challenging for novices, so more and more car owners now choose automatic transmission. The main automatic transmissions commonly used in vehicles are hydraulic automatic transmissions (AT), mechanical automatic transmissions (AMT) and metal belt automatic transmissions (CVT).

CVT is also called continuously variable transmission because it can achieve continuously variable transmission.

Among the three types of automatic transmissions, hydraulic automatic transmissions are the most mature and widely used. Therefore, when talking about automatic transmissions, unless the type is specifically indicated, the default will be a hydraulic automatic transmission.

Manual transmission cars have three pedals: the accelerator pedal, the brake pedal, and the clutch pedal.

Whereas, automatic transmission cars only have two pedals, the accelerator pedal and the brake pedal, and there is no clutch pedal.

Manual transmission (MT): The driver needs to press the clutch and manually shift the gear lever to change the gear meshing position and gear ratio in the transmission, so as to achieve the purpose of shifting.

Automatic Transmission (AT): Transmits power through hydraulics and is controlled by a computer. It adjusts the appropriate speed to match the engine's power output according to the speed and road conditions. The driver only needs to control the speed of the vehicle and the output of the engine, which is the accelerator and brake.

There are three main differences between manual and automatic transmissions:

Different control modes.

Manual transmission requires the driver to grasp the opportunity and cooperate with the clutch to shift, which requires rich driving experience, which can fully stimulate the driver's driving desire and sense of achievement. The automatic transmission is operated by the gearbox according to a set program without human intervention. Practical and labor-saving, making driving simple and easy for novices.

The structure is different. The manual transmission shifts gears entirely through gears and synchronizers, transmitting power to the output shaft connected to it, and has a simple and reliable structure. A hydraulic automatic transmission is a complex device that works in coordination with electronic, hydraulic, and mechanical devices.

Its structure has changed a lot, and processing, cost, and maintenance are difficult.

Transmission efficiency. Because different manual transmissions are completely mechanical, while automatic transmissions are driven by torque converters, there are differences in work efficiency, which directly leads to differences in fuel consumption. For cars of the same brand and displacement, manual transmission can save about 10% fuel compared with automatic transmission.

1.The automatic transmission uses a planetary gear mechanism to change the speed according to the degree of the accelerator pedal and the change of vehicle speed. And the driver can control the speed only by manipulating the accelerator pedal.

2.Generally speaking, there are three types of automatic transmissions used in automobiles: hydraulic automatic transmissions, hydraulic automatic transmissions, electric automatic transmissions, graded mechanical automatic transmissions, and continuously mechanical automatic transmissions.

The most common is a hydraulic automatic transmission. The automatic transmission consists of a hydraulically controlled gearing system, including an automatic clutch and an automatic transmission. It automatically shifts gears according to changes in throttle opening and vehicle speed.

3.An electronic automatic transmission usually consists of a torque converter, a planetary gear transmission system, a shift actuator, a hydraulic control system, and an electronic control system.

1. The automatic transmission uses the planetary gear machine to change the speed according to the degree of the accelerator and the speed of the vehicle. The driver only needs to control the speed of the vehicle by manipulating the accelerator pedal.

2. Generally speaking, there are the following types of automatic transmissions commonly used in automobiles: hydraulic automatic transmissions, hydraulic transmission automatic transmissions, electric transmission automatic transmissions, stepwise mechanical automatic transmissions and continuously variable mechanical automatic transmissions. Among them, the most common is a hydraulic automatic transmission.

The hydraulic automatic transmission is mainly composed of a hydraulically controlled gear transmission system, which mainly includes two parts: automatic clutch and automatic transmission. It automatically shifts gears according to the opening of the throttle and changes in vehicle speed.

3. The electronically controlled automatic transmission is usually composed of five parts: hydraulic torque converter, planetary gear transmission system, cornering actuator, hydraulic control system and electronic control system.

There are four common types of automatic buried or transmission: electronically controlled hydraulic automatic transmission (AT), electronically controlled mechanical automatic transmission (AMT), electronically controlled mechanical continuously variable automatic transmission (CVT), and dual-clutch transmission (DCT).

The common components are hydraulic torque converter, planetary gear mechanism, clutch, brake, oil pump, filter, pipeline, control valve body, Xinzao speed pressure regulation bending device, etc., according to the function of these components, it can be divided into five parts: hydraulic torque converter, variable speed gear mechanism, oil supply system, automatic shift control system and shift control mechanism.

There are four types of automatic transmissions:

1. The hydraulic automatic gearbox realizes automatic transmission through the combination of hydraulic transmission and planetary gears, which is generally composed of hydraulic torque converter, planetary gear mechanism, shift actuator, shift control system, sliding shed shift control mechanism and other devices;

2. The characteristic of mechanical continuously variable automatic transmission is that the gear ratio is not an intermittent point, but a series of continuous values, so as to better coordinate the external driving conditions of the vehicle and the engine load, and give full play to the potential of the engine;

3. The electronically controlled mechanical automatic transmission is improved on the basis of the traditional manual gear transmission, which is a mechatronic and hydraulic integrated self-defeating sliding transmission that combines the advantages of AT (automatic) and MT (manual);

4. The dual-clutch automatic transmission adopts two sets of clutches, and the two sets of clutches work alternately to achieve the effect of backlash-free shifting.

What is an automatic transmission? There are four common types of automatic transmissions, which will take you to understand.

The differences between manual transmission and automatic transmission are: 1. Different shift methods: manual transmission requires the driver to shift the gear by himself; An automatic transmission is a shift operation that the car performs on its own.

2. The operation mode is different: the manual transmission needs to press the clutch to hang 1 to 5 gears and reverse; Automatic transmissions do not require frequent gear changes, which are typically forward, neutral, park, and reverse gears. The working principle of a manual transmission is:

By shifting the fork, the transmission ratio of the meshing gear is changed, and then the driving torque is changed to suit different working conditions. The automatic transmission does not require the driver to manually change gears, and the vehicle will automatically select the appropriate gear according to the driving speed and traffic conditions.