What is Automatic Transmission in Cars
Introduction
Automatic transmission is a type of transmission that allows the driver to shift gears without using a clutch pedal. This is done by using a series of gears and hydraulics to automatically select the correct gear for the current driving conditions.
How Does Automatic Transmission Work?
Automatic transmissions use a series of gears to transmit power from the engine to the wheels. These gears are arranged in a planetary gearset, which allows the transmission to change gears smoothly and efficiently.
The planetary gearset consists of a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the engine, while the planet carrier is connected to the output shaft. The ring gear is fixed to the transmission case.
When the transmission is in gear, the sun gear rotates and causes the planet carrier to rotate around it. This, in turn, causes the ring gear to rotate. The speed of the output shaft is determined by the ratio of the sun gear to the ring gear.
The transmission also uses a series of hydraulics to control the shifting of gears. These hydraulics are controlled by the transmission control module (TCM), which is a computer that monitors the engine speed, vehicle speed, and throttle position.
The TCM uses this information to determine the correct gear for the current driving conditions. It then sends a signal to the hydraulics, which shift the gears accordingly.
Types of Automatic Transmissions
There are two main types of automatic transmissions: conventional automatic transmissions and continuously variable transmissions (CVTs).
Conventional automatic transmissions use a series of gears to transmit power from the engine to the wheels. CVTs, on the other hand, use a belt or chain to transmit power. This allows CVTs to change gears smoothly and efficiently, without any noticeable shift points.
Advantages of Automatic Transmissions
Automatic transmissions offer a number of advantages over manual transmissions, including:
- Ease of use: Automatic transmissions are much easier to use than manual transmissions, especially for drivers who are new to driving.
- Reduced driver fatigue: Automatic transmissions can help to reduce driver fatigue, especially in stop-and-go traffic.
- Improved fuel economy: Automatic transmissions can help to improve fuel economy by selecting the correct gear for the current driving conditions.
Disadvantages of Automatic Transmissions
Automatic transmissions also have some disadvantages, including:
- Cost: Automatic transmissions are more expensive to purchase and maintain than manual transmissions.
- Weight: Automatic transmissions are heavier than manual transmissions, which can reduce fuel economy.
- Complexity: Automatic transmissions are more complex than manual transmissions, which can make them more difficult to repair.
Conclusion
Automatic transmissions are a popular choice for drivers who want an easy-to-use and fuel-efficient transmission. However, automatic transmissions are more expensive to purchase and maintain than manual transmissions, and they are also more complex.
Ultimately, the best type of transmission for you will depend on your individual needs and preferences.
