What is the principle of an AT transmission?
3 Answers
AT transmissions achieve automatic gear shifting through the coordination of a torque converter and a gear transmission system. The specific working principle involves assembling two turbine blades within a space filled with hydraulic oil, which are connected to the power input and output ends respectively. The turbine at the power input end generates a powerful vortex to drive the turbine at the output end, thereby transmitting power. The advantages and maintenance methods of AT transmissions are as follows: Advantages of AT transmissions include: using clutch shifting to achieve uninterrupted power shifting, ensuring smooth gear changes; employing a torque converter to buffer engine shocks and vibrations, providing excellent ride comfort; due to the torque converter, the vehicle exhibits good low-speed driving capability; and wide applicability across various vehicle models. Maintenance methods: Regularly check the transmission fluid level: After starting the engine, warm up the transmission fluid to approximately 50 degrees Celsius, then move the gear selector through each position for 2 seconds before placing it in the parking gear. At this point, the fluid level on the dipstick should be between the maximum and minimum marks. If it is insufficient, promptly add the same quality fluid. Timely replacement of automatic transmission fluid: The fluid replacement interval for most automatic transmissions is generally two years or 40,000 to 60,000 kilometers. However, it is recommended to replace the fluid 2,000 to 3,000 kilometers earlier. The specific replacement interval can also be found in the vehicle owner's manual. In 2010, a better fluid replacement method was dynamic replacement, which uses specialized transmission fluid exchange equipment. During the operation of the transmission, the old fluid is thoroughly circulated and drained before adding new transmission fluid, achieving a fluid exchange rate of over 90 degrees Celsius and ensuring effective fluid replacement. Vehicle owners should develop the habit of proactive inspection, maintenance, and care. They can learn some basic vehicle maintenance and care knowledge, carefully read the vehicle's user manual, and remember essential data. Scientific vehicle maintenance ensures the vehicle remains in good technical condition and guarantees driving safety.
After driving for so many years, I've realized that the principle of automatic transmissions is actually quite ingenious. It primarily relies on a component called the torque converter to connect the engine and gears, responsible for transmitting power and cushioning impacts—just like a smart butler. Then, the planetary gear set plays a central role, altering gear ratios to determine vehicle speed; for instance, using a low gear to increase torque during acceleration and switching to a high gear for fuel efficiency at high speeds. All of this is monitored by the hydraulic system and electronic control unit, which adjust based on throttle depth and wheel speed to achieve seamless gear shifts. This design makes driving incredibly smooth, eliminating the need for manual clutch and gear lever operation, especially during traffic jams or uphill climbs. Modern cars also incorporate more sensors to ensure efficiency and durability, but the fundamental principle remains unchanged: automating gear shifts to let you enjoy the freedom of driving.
I've driven quite a few cars, and my favorite is still the convenience of automatic transmissions. In principle, the transmission automatically shifts gears to match speed and engine RPM, using a torque converter instead of a clutch to handle power transfer. In daily driving, it responds when you press the accelerator, shifting smoothly without jerking—like a seamless collaboration with the machine, making both city commutes and long trips effortless. The core lies in the gear combinations adapting to demand, with the computer constantly calculating the optimal timing for shifts to keep you from distraction. This also reduces the risk of manual operation errors and related failures. Simply put, it hides complex technology behind the scenes, delivering a more relaxed driving experience for everyday drivers. Regular maintenance is key—don’t wait for problems to arise before addressing them.
