Patent ID: 7244154
Filing Date: 2007-07-17
Classification: B63H

Abstract:
1. A drive system in a multi-engine marine vessel having port and starboard propellers, said drive system comprising: a forward engine mounted along the longitudinal centerline of the vessel and having an output facing aft; a rear engine mounted along the longitudinal centerline of the vessel, in longitudinal alignment with said forward engine, and having an output facing forward; a first power train; a second power train; first clutch means for selectively engaging and disengaging said forward engine with said first power train; second clutch means for selectively engaging and disengaging said rear engine with said second power train; third clutch means for selectively engaging said first power train with said second power train; a port transmission means for drivingly engaging and rotating the port propeller in forward and reverse operation, and for disengaging the port propeller when operated to neutral; a starboard transmission means for drivingly engaging and rotating the starboard propeller in forward and reverse operation, and for disengaging the starboard propeller when operated to neutral; an under/overdrive unit on an output of each of said first and second power trains, and each of said under/overdrive units being drivingly linked to a respective one of said port and starboard transmission means, and said under/overdrive units being structured and disposed for changing and balancing a reduction gear ratio between single engine drive of both of said port and starboard propellers and twin engine drive of said port and starboard propellers.