Hydraulic transmission pump assembly having a differential actuation and integrated line pressure control

摘要

A hydraulic transmission pump assembly including a pump adapted to provide fluid under pressure to predetermined components in a transmission, an electric motor operatively coupled to said pump, and a line pressure control device in electrical communication with said electric motor. The line pressure control device is operable to control the electric motor as to cause it to drive the pump when engine speeds are below a predetermined level such that the pump provides fluid at a predetermined volume and pressure to the transmission during this operating condition. A differential gear assembly is also included that is interposed between an engine and the electric motor, the differential gear assembly acting to drive both the pump and the electric motor when engine speeds are above the predetermined level such that the pump provides fluid at a predetermined volume and pressure to the transmission and the electric motor provides generated electricity.