The principle of transmission of automobile transmission

The transmission is a gear transmission that can be fixed or stepped to change the transmission ratio between the output shaft and the input shaft. Also known as gearbox. The transmission consists of a transmission mechanism and a transmission mechanism, which can be made into a separate transmission mechanism or assembled in the same housing with the transmission mechanism. The transmission mechanism is mostly driven by ordinary gears, and some are also driven by planetary gears. General gear transmissions generally use slip gears and clutches. Slip gears have multiple slip gears and shift slip gears. The use of triple slip gears, large axial size; variable speed gears with displacement, compact structure, but the transmission ratio change is small. Clutch clutch and friction type points. When using the meshing type clutch, the speed change should be stopped or the speed difference is very small. The friction type clutch can be used to shift speed at any speed difference during operation, but the bearing capacity is small, and the two axles cannot be guaranteed to be in strict synchronization. In order to overcome this shortcoming, a friction plate is mounted on the meshing type clutch, and the friction plate is used to bring the driven wheel to the synchronous rotation speed before performing the engagement. Planetary geared transmissions can be controlled with brakes. Transmissions are widely used on machine tools, vehicles and other machines that need to change gears. The machine tool spindle is usually installed in the transmission, so it is also called the spindle box. Its compact structure facilitates centralized operation. Transmissions that change the feed on the machine are called feed boxes.

The automobile transmission changes the transmission ratio and changes the rejection of the crankshaft of the engine to meet the requirements of different driving conditions such as starting, acceleration, running and overcoming various road obstacles. Popularly divided into manual transmission (MT), automatic transmission (AT), manual / automatic transmission, stepless transmission. The transmission is one of the most important components in the automotive powertrain.

(1) Change the transmission ratio to meet the needs of different driving conditions for traction, so that the engine can work under favorable conditions as far as possible to meet the possible speed requirements. Change the size of the car's travel speed and the torque on the car's drive wheels over a wide range. Due to different driving conditions of the car, the required driving speed and driving torque of the car can be varied within a wide range. For example, the speed on a highway should be able to reach 100km/h, while in urban areas, the speed is often around 50km/h. When the empty car is driving on a straight road, the running resistance is very small; when it is fully loaded uphill, the running resistance is very large. The characteristic of the automobile engine is that the speed change range is small, and the torque variation range cannot meet the actual road conditions.

(2) to achieve reverse driving, used to meet the needs of the car's reverse travel. To achieve reverse driving cars, the engine crankshaft generally can only turn in one direction, and the car sometimes need to be able to reverse the driving, therefore, often using the reverse gear set in the gearbox to achieve the reverse car driving.

(3) The transmission of power is interrupted, and the power transmission to the drive wheels is interrupted when the engine is started, idling, or when the vehicle shifts gears or needs to stop for power output.

(4) To achieve neutral, the transmission may not output power when the clutch is engaged. For example, it may be ensured that the driver releases the clutch pedal from the driver's seat when the engine is not stalled.