What is the primary purpose of a torque converter?

The primary purpose of a torque converter is to multiply torque as it slows down. In an automotive context, a torque converter is a type of fluid coupling that allows for the transfer of rotary power while enabling the engine to idle without stalling. As the engine speed increases, the turbine inside the converter helps to increase the torque being transmitted to the transmission. This means that during acceleration, the converter can multiply the engine's torque, making it easier for the vehicle to start moving or to climb hills without requiring the engine to reach high RPMs.

This functionality is particularly beneficial during low-speed operations and when the vehicle is under a heavy load, ensuring that the engine can operate at its optimal RPM while still providing sufficient torque to the drivetrain. By effectively managing power and torque through fluid dynamics, the torque converter plays a crucial role in the performance and efficiency of an automatic transmission system.