Patent ID: 8664794

Claim:
An apparatus comprising: a first shaft rotationally coupled to a first power source; a second shaft configured coaxially and counter-rotating to said first shaft, wherein said second shaft is rotationally coupled to a second power source; a first driver gear rotationally coupled to said first shaft; a second driver gear rotationally coupled to said second shaft; a first driven gear engaged with said first and second driver gears so that the point at which said first driver gear engages said first driven gear is phase shifted approximately 180 degrees from the point at which said second driver gear engages said first driven gear; a second driven gear engaged with said first and second driver gears so that the point at which said first driver gear engages said second driven gear is phase shifted approximately 180 degrees from the point that said second driver gear engages said second driven gear; a first load rotationally coupled to said first driven gear; a second load; and a first clutch rotationally coupled to said second driven gear, wherein said first clutch is constructed and arranged to selectively rotationally couple said second driven gear to said second load such that said apparatus can be operated with either said first load or with both said first and second loads coupled to said first and second power sources to account for variations in said first and second power sources.