Patent ID: 7220201

Claim:
An electrically variable transmission comprising: an input member to receive power from an engine; an output member; first and second motor/generators; first and second differential gear sets each having first, second and third members; said input member not being continuously connected with any member of said gear sets, and said output member being continuously connected with a member of said gear sets; a first interconnecting member continuously connecting said first member of said first gear set with said first member of said second gear set; a second interconnecting member continuously connecting said second member of said first planetary gear set with said second member of said second planetary gear set; said first motor/generator being continuously connected with a member of said first or second gear set; said second motor/generator being continuously connected with a member of said first or second gear set which is different from said member connected with said first motor/generator; a first torque transfer device selectively connecting said input member with a member of said first or second planetary gear set, or with said first or second interconnecting member; a second torque transfer device selectively connecting said input member with a member of said first or second planetary gear set, or with said first or second interconnecting member, this member being different from the one connected by said first torque transfer device; a third torque transfer device selectively connecting said input member with a member of said first or second planetary gear set, or with said first or second interconnecting member, this member being different from the one connected by said first or second torque transfer device; a fourth torque transfer device connected in parallel with one of said motor/generators for braking rotation thereof; a fifth torque transfer device connected in parallel with the other of said motor/generators for braking rotation thereof; and wherein said first, second, third, fourth and fifth torque transfer devices are engageable singly or in pairs to provide an electrically variable transmission with a continuously variable range of speed ratios and four fixed forward speed ratios.