CVT (Continuously Variable Transmission) and automatic transmission (AT) are two types of transmissions used in cars. Although they have some similarities, they also have significant differences:
Working principle:
* CVT: The use of metal belts or chains that pass through tapered pulleys of variable diameter, allowing the gear ratio to continuously vary between a fixed minimum and maximum gear ratio.
* Automatic transmission: Uses a set of fixed gears, between which the transmission switches depending on speed and load.
Number of gears:
* CVT: Continuously Variable, which means it has an infinite number of gears.
* Automatic transmission: Usually has from 4 to 10 fixed gears.
Control:
* CVT: Controlled by an electronic control unit (ECU), which adjusts the gear ratio changes depending on the input data (speed, load, throttle position).
* Automatic Transmission: Often uses a hydraulic system controlled by the ECU to shift between gears according to programmed conditions.
Acceleration:
* CVT: Can provide smoother, more linear acceleration because the gear ratio can be continuously adjusted to maintain optimal engine power.
* Automatic transmission: Provides clearer and more noticeable gear shifting, depending on the specific transmission design.
Fuel efficiency:
* CVT: Typically more economical at low speeds because it can maintain lower engine speeds for a given vehicle speed.
* Automatic: Can be more economical at higher speeds because it has a wider ratio width.
Reliability:
*CVT: May have higher maintenance and repair costs because the mechanism is more complex and more sensitive to belt or chain wear.
* Automatic transmission: Usually more reliable, but also requires regular maintenance (oil and filter changes).
Weight and dimensions:
* CVT: Typically more compact and lighter than automatic transmissions.
* Automatic transmission: More voluminous and heavier.
Application:
* CVT: Often used in compact and fuel-efficient cars, as well as hybrid cars.
* Automatic Transmission: Used in a wide range of vehicles, from subcompact to large luxury models.