Fluid Pump: Description and Operation

Description

ISG system has a standard Mechanical Oil Pump(MOP) linked to the input shaft to generates oil pressure when input shaft rotates. ISG system also has an Electric Oil Pump(EOP). Because the ISG features Auto-Stop which starts and stops the engine as needed. The Auto-Stop feature prevents the Mechanical Oil Pump(MOP) from operating and building enough pressure for the transaxle to operate. When the vehicle comes to a stop with the engine off, Mechanical Oil Pump(MOP) cannot generate sufficient oil pressure during the initial startup (below 5 KPH) or during low speed driving.
For these reasons, the Electric Oil Pump(EOP) takes on this role as an additional device that can generate the required oil pressure when the vehicle comes to a stop or during low speed driving.The Electric Oil Pump(EOP) supplies oil pressure to the Under Drive Brake(UD/B).