Torque converter

A torque converter is a type of fluid coupling that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the torque converter connects the power source to the load. It is usually located between the engine's flexplate and the transmission. The equivalent location in a manual transmission would be the mechanical clutch. The main characteristic of a torque converter is its ability to increase torque when the output rotational speed is so low, it allows the fluid, coming off the curved vanes of the turbine to be deflected off the stator while it is locked against its one-way clutch, thus providing the equivalent of a reduction gear. This is a feature beyond the simple fluid coupling, which can match rotational speed but does not multiply torque and thus reduces power. By far the most common form of torque converter in automobile transmissions is the hydrokinetic device described in this article. There are also hydrostatic systems which are widely used in small machines such as compact excavators. There are also mechanical designs for continuously variable transmissions and these also have the ability to multiply torque. They include the pendulum-based Constantinesco torque converter, the Lambert friction gearing disk drive transmission and the Variomatic with expanding pulleys and a belt drive. Automatic transmissions on automobiles, such as cars, buses, and on/off highway trucks. Forwarders and other heavy duty vehicles. Marine propulsion systems. Industrial power transmission such as conveyor drives, almost all modern forklifts, winches, drilling rigs, construction equipment, and railway locomotives. Torque converter equations of motion are governed by Leonhard Euler's eighteenth century turbomachine equation: The equation expands to include the fifth power of radius; as a result, torque converter properties are very dependent on the size of the device.