Oil Pump Description: Structure/Operation

The outer rotor and inner rotor are installed in the oil pump housing.
The inner rotor in the oil pump housing is driven by the torque converter.
When the inner rotor in the oil pump rotates, the ATF is drawn to the oil pump. The discharge amount is proportional to the rotating speed of the torque converter.

Fig 1: Identifying Oil Pump Structure/Operation
Courtesy of MAZDA MOTORS CORP.