Modern vehicles feature a few versions of automatic transmissions.

Most popular kind of automatic transmissions found in vehicles is that the automatic transmissions this technique uses a fluid coupling in situ of a clutch and accomplishes gear changes by locking and unlocking a system of planetary gears a simple planetary gear set consists of a single Sun gear three planet gears a planet carrier and a ring gear each of those 3 elements are often the input the output or are often command stationary selecting that piece plays that role determines the gear magnitude relation for the gear set in first gear the Sun gear is driven by the torque converter which is driven by the engine the ring gear is held stationary by a multi-plate break the planet carrier is connected to the output and drives the wheels of the car the sakir ratio of three point four is to one is obtained and the output speed is slower than the input speed in second gear the Sun gear is driven by the torque converter all the parts of the planetary gear set is held stationary and the ring gear is connected to the output and drives the wheels of the car the sagir ratio of 1 is to 1 is obtained and the output speed is equal to the input speed in third gear the planet carrier is driven by the torque converter the Sun gear is held stationary the ring gear is connected to the output and drives the wheels of the car (automatic transmissions) the sagir ratio of 0.7 is to one is obtained and the output speed is faster than the input speed in reverse gear the Sun gear is driven by the torque converter the planet carrier is held stationary the ring gear is connected to the output and drives the wheels of the car the sagir ratio of -2 points 4 is to 1 is obtained and the output speed is slower than the input speed you. automatic transmissions
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