Automobile Transmission and Its Working Principle?

2 Answers
RebeccaFitz
09/03/25 6:29am
The function and principle of a transmission are primarily to alter the gear ratio, expand the range of torque and speed variations of the drive wheels to adapt to frequently changing driving conditions, while allowing the engine to operate under favorable conditions. Transmissions are divided into manual and automatic types. Manual transmissions mainly consist of gears and shafts, achieving speed and torque changes through different gear combinations. Automatic transmissions, on the other hand, achieve speed and torque variations through hydraulic transmission and gear combinations. Below are the working principles of different transmissions: 1. Manual Transmission Principle: By shifting the gear lever, the driving gear on the intermediate shaft is switched, combining with gears of different sizes on the power output shaft to change the torque and speed of the drive wheels. The engine's power input shaft is indirectly connected to the power output shaft via an intermediate shaft. 2. Automatic Transmission Principle: Automatic transmissions use planetary gear mechanisms to change speed. They automatically shift gears based on the degree of throttle pedal pressure and changes in vehicle speed, requiring the driver only to control the speed via the accelerator pedal. 3. AT Transmission Working Principle: The torque converter is the most distinctive component of an AT transmission. It directly inputs engine power and transmits torque while also serving a clutch function. The pump wheel drives the turbine to rotate via fluid, and with the addition of a stator between the pump wheel and turbine, a speed difference between the pump wheel and turbine is achieved through reaction force, enabling speed and torque changes.
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VanAlivia
09/15/25 7:54am
The car transmission sounds pretty cool—it's like the master regulator between the engine and the wheels. Simply put, when the engine outputs high RPM but low torque, the transmission adjusts the gear ratio to keep the vehicle running smoothly at different speeds. For example, with a manual transmission, you press the clutch to select gears, relying on linkages and gear engagement. Automatic transmissions are smarter, using a computer-controlled hydraulic system to shift gears automatically. The core principle is that the input shaft connects to the engine, and the output shaft connects to the wheels. Changing the gear ratio provides more power for climbing hills and better fuel efficiency on flat roads. From my daily driving experience, using the transmission well can make the car smoother and more fuel-efficient. New drivers can easily handle automatics, while seasoned manual drivers can enjoy precise control.
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