Patent ID: 7415820

Claim:
A powertrain comprising: a first pump configured to supply hydraulic pressure; a first power source operatively connected to the first pump and configured to selectively power the first pump; a second pump configured to supply hydraulic pressure; a second power source operatively connected to the second pump and configured to selectively power the second pump; a conduit defining a passageway; a transmission in fluid communication with the passageway; and a valve assembly; said valve assembly being sufficiently configured to operate in a first mode of operation in which the valve assembly provides fluid communication between the first pump and the passageway and prevents fluid communication between the second pump and the passageway, a second mode in which the valve assembly provides fluid communication between both of the first and second pumps and the passageway, and a third mode in which the valve assembly prevents fluid communication between the first pump and the passageway and provides fluid communication between the second pump and the passageway.