Types of automatic gearboxes in cars: AMT, CVT and more
Automatic transmissions are taking over modern-day cars, replacing the good-old manual gearboxes. These sophisticated systems are known by a range of acronyms - AMT, iMT, CVT, torque converters, and DCT. Now, every type of automatic transmission has its own set of features and functions that set it apart from the rest. Let's take a closer look at how they work.
AMT: A blend of manual and automatic features
Automated Manual Transmission (AMT) is a widely used gearbox type in many vehicles. It works like a manual transmission but uses a hydraulic actuator system and an electronic control unit to engage/disengage the clutch, removing the need for a physical clutch lever. This system even provides a manual mode, letting the drivers shift gears manually if they want.
iMT: Manual gear shifting without clutch operation
Intelligent Manual Transmission (iMT) is yet another kind of automatic gearbox, which is similar to AMT. The only difference here is the H-pattern gearshifts, which the driver has to shift manually but without using the clutch. An 'intention sensor' on the gear lever tells the Transmission Control Unit (TCU) to change gears when the driver initiates it, making it a unique manual-automatic blend.
CVT: Infinite gear ratios for smooth acceleration
Continuously Variable Transmission (CVT) is a special kind of automatic gearbox, which is usually seen in scooters and some car models. It employs two cone-shaped pulleys joined by a belt, where one pulley is connected to the engine and the other to the wheels. With rising engine rpm, the belt on the pulleys adjusts to keep tension, offering infinite gear ratios for smooth acceleration.
Torque Converter: Ideal for powerful engines
A Torque Converter (TC) is the oldest kind of automatic gearbox, one that has been around for decades. It self-changes gears on the move with a complex hydraulic system and planetary gears, which makes it perfect for powerful engines. Such a transmission allows a lot of torque to be transferred at low RPMs, which is why it is the go-to option for most high-end cars.
DCT: Fast and seamless gear shifts
Dual Clutch Transmission (DCT) is another automatic gearbox that is becoming increasingly popular in India, particularly with brands like Volkswagen, SKODA, Hyundai, and Kia. As the name suggests, a DCT employs two clutches for selecting odd and even gears respectively. It works like an AMT but keeps the next gear engaged for faster, seamless shifts. This transmission also allows manual shifting, giving drivers more control over their vehicle's performance.
