How Torque Converters work?

My car at the moment is broken its seems after it warmed up and you then try to drive the car engine works fine but the transmission or torque converter is having issues. The revs will start low as normal but then it seems the transmission slips and allows the engine to rev and i get loss of power.

this isn't the first time this has happened to me. The last this did happen to me i had to replace the whole transmission (I'm not sure if the torque converter was replaced at that time)

before reading this i had no idea how a torque converter worked.

http://www.drive.subaru.com/Fall02_TorqueConvert.htm

A key component of the Subaru drivetrain, the torque converter acts as the bridge between the engine and the automatic transmission. It’s not only a vital link in your vehicle’s drivetrain, it also helps define what many refer to as the “feel” you experience as you drive.