What are the principles of various transmissions?
3 Answers
Transmission working principles are as follows: 1. Manual transmissions mainly consist of gears and shafts, achieving speed and torque variation through different gear combinations. 2. Automatic transmissions (AT) are composed of a torque converter, planetary gears, and a hydraulic control system, achieving speed and torque variation through hydraulic power transmission and gear combinations. The torque converter is the most distinctive component of an AT, consisting of a pump impeller, turbine, and guide wheel, directly inputting engine power to transmit torque and perform clutch functions. 3. If liquid is used instead of air as the medium for transmitting kinetic energy, the pump impeller will drive the turbine to rotate through the liquid, with a guide wheel added between the pump impeller and turbine to improve liquid transmission efficiency. Since the torque converter's automatic speed and torque variation range is not large enough and efficiency is relatively low, several rows of planetary gears are connected in series behind the turbine to improve efficiency. The hydraulic control system automatically operates the planetary gears according to engine working conditions, thereby achieving automatic gear shifting.
From an engineer's perspective on transmission principles: Manual transmissions rely on the driver pressing the clutch to interrupt power, then moving the gear lever to change gear engagement and adjust speed ratios for speed control. Automatic transmissions use a torque converter to transmit engine power, combining with planetary gear sets to automatically shift gears, where internal hydraulic systems drive valve movements for gear changes, reducing manual operations. Dual-clutch transmissions feature two independent clutches - one controlling odd-numbered gears while the other pre-selects even-numbered gears, achieving lightning-fast seamless shifts. Continuously Variable Transmissions (CVT) employ variable-diameter pulleys and belt systems that continuously alter gear ratios during operation without fixed gears, offering high efficiency but potential slippage issues. Modern automated manual transmissions add electronic controls to manual systems, using computers to shift gears, making them suitable for novice drivers. These principles fundamentally manage engine output to optimize fuel economy and driving smoothness.
I've been driving for decades and have experienced various transmissions. The joy of a manual lies in the clutch pedal, gear stick, and the crisp engagement of gears, requiring precise coordination for every acceleration—complex to operate but offering strong control. Automatics are much easier, with paddle shifters or gear levers handling shifts automatically, the torque converter smoothing out power surges, making driving as smooth as ice skating, and no stalling at stops. Dual-clutch transmissions are even smoother, with two clutches alternating shifts, delivering instant gear changes and strong acceleration. As for CVTs, pressing the throttle eliminates jerks, as the belt glides over pulleys, providing linear speed increases and better fuel efficiency, though with softer handling. The core principle is to distribute power more efficiently, adapting to city traffic or highway cruising. From old cars to new, I've felt how they enhance comfort and safety.
