Patent ID: 7727100

Claim:
A hybrid electro-mechanical transmission connectable with a power source, comprising: an input member connected with the power source; an output member; a planetary gear set having a first, a second, and a third member; first and second motor/generators; a battery operatively connected to the motor/generators for receiving power therefrom and delivering power thereto; wherein the input member is operatively connected with the first member; wherein the first motor/generator is operatively connected for rotation with the second member; wherein the second motor/generator is operatively connected for rotation at the same speed as the output member; a first torque-transmitting mechanism engagable to connect the second motor/generator for rotation with the third member; wherein the battery and second motor/generator provide an electric-only operating mode to power the output member when the first torque-transmitting mechanism is not engaged; the power source, planetary gear set and first motor/generator thereby being disconnected from the output member during the electric-only operating mode to prevent parasitic drag; wherein the first torque-transmitting mechanism is a one-way clutch that is automatically in a disengaged, overrunning state during the electric-only operating mode; and wherein the transmission has no torque-transmitting mechanisms engaged during the electric-only operating mode.