The torque converter is what transfers energy in the motor towards the gearbox. It's really a fluid coupling that works by using hydraulic pressure to multiply the torque with the motor. The torque converter is manufactured up of a few primary sections: the pump, the turbine, and the stator. Essentially https://filter-gearbox91233.thekatyblog.com/32826148/an-unbiased-view-of-filter-gearbox