Along with the transmission, the basic function of the transmission is to reduce the relatively high engine output speed and increase the torque applied to the wheels at the slow wheel speed of the vehicle. Torque converters integrated with many automatic transmissions provide significant torque multiplication at start-up and low speed. The transmission design affects vehicle fuel consumption in two ways. First, increasing the number of gear repair ratios and increasing the gear ratio will allow the internal combustion engine to operate more frequently in the high efficiency region.
Car engines Are Currently being Much more Fuel Productive
Planetary Automatic Transmission
The automatic transmission (AT) is currently the main transmission in the United States and will continue to be the main transmission in 2025 (EPA 2014). Most automatic transmissions use planetary gear sets and are easy to operate and are most popular due to their soft running feel during idling. We also benefit from more than 70 years of continuous development and cost-effective improvements. In addition to providing a fluid coupling between the engine and the power-train, a smooth firing feel can be achieved by providing a torque converter that provides high torque multiplication during launch.
A single planetary gear set can provide a limited number of gear ratios. You can combine gear sets to increase the number of available gear ratios. Modern transmissions are equipped with planetary gear sets that are differently configured to provide the various gear ratios required by the vehicle. The following three types of planetary gear sets are commonly used in automatic transmissions.
The Simpson gear set has two planetary carriers and two ring gears with a common sun gear. In addition to the three forward gears, neutral and reverse gear are also available.
- The Ravigneaux tools features 2 sun dive with a regular ring gear and two planet gear carriers. It presents 4 onward and basic and invert gears.
- The Lapelletier tools hooks up a hassle-free planetary tools to the Ravigneaux gear set. That supplies 6-8 forward issues.