Patent ID: 8414437

Claim:
A hybrid transmission operatively connected with an engine, comprising: an input member operatively connected with the engine; an output member; a plurality of selectively engageable torque-transmitting mechanisms; a gearing arrangement; first and second motor/generators operatively connected with the gearing arrangement; wherein a first of the torque-transmitting mechanisms is engaged to establish a hybrid series operating mode between the input member and the output member; wherein only a second of the torque-transmitting mechanisms is engaged to establish a compound-split operating mode between the input member and the output member; wherein a shift between the hybrid series operating mode and the compound-split operating mode is synchronous without slipping the torque-transmitting mechanisms; wherein the gearing arrangement includes multiple planetary gear sets, each planetary gear set having multiple gear members; wherein powerflow from a first group of the gear members to a second group of the gear members is via an electrical path through the motor/generators in the series operating mode; and wherein powerflow from the first group of gear members to the second group of gear members is via a mechanical path established by engaging the second torque-transmitting mechanism in the compound-split operating mode; wherein the planetary gear sets include a first, a second and a third planetary gear set; wherein the input member is connected for common rotation with a first member of the first planetary gear set; wherein the first motor/generator is connected for common rotation with a second member of the first planetary gear set and with a first member of the second planetary gear set; wherein the third member of the first planetary gear set is selectively grounded to the stationary member by engagement of the first torque-transmitting mechanism and is continuously connected for common rotation with the first member of the third planetary gear set; wherein the second motor/generator is continuously connected for common rotation with the second member of the second planetary gear set and with the second member of the third planetary gear set; wherein the output member is continuously connected for common rotation with the third member of the third planetary gear set; and wherein the second torque-transmitting mechanism is selectively engageable to connect the third member of the second planetary gear set for common rotation with the interconnected third member of the first planetary gear set and first member of the third planetary gear set.