Patent ID: 7241242
Filing Date: 2007-07-10
Classification: F16H

Abstract:
1. A two-mode compound-split powertrain having a hydraulically continuously variable transmission comprising: an engine; an input shaft continuously driven by said engine; an output drive mechanism; a first hydraulic unit and a second hydraulic unit, wherein neither of said first hydraulic unit or said second hydraulic unit is directly connected to said input shaft or said output drive mechanism to provide the compound-split configuration; a planetary gear arrangement having a first planetary gearset having three rotatable members; a second planetary gearset having three rotatable members; a first selectively engageable torque-transmitting mechanism engageable to establish both a forward and a reverse operation in said continuously variable transmission; and a second selectively engageable torque-transmitting mechanism; said first members of said planetary gearsets are continuously interconnected and drivingly connected with said first hydraulic unit, said second rotatable members of the planetary gearsets are drivingly interconnected and continuously drivingly connected with said input shaft, said third member of said first planetary gearset is continuously drivingly connected with said second hydraulic unit, and said third member of said second planetary gearset is selectively connectible with said transmission output mechanism through said second selectively engageable torque-transmitting mechanism wherein said transmission has a first zero speed point at which said first hydraulic unit does not rotate and a second zero speed point at which said second hydraulic unit does not rotate, and wherein at least one of said first hydraulic unit and said second hydraulic unit is selectively connectable to a stationary portion of said transmission for establishing one of said zero speed points.