Electrically variable transmission having two planetary gear sets with one fixed interconnection and a stationary member

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;
• an interconnecting member continuously connecting said first member of said first gear set with said first member of said second gear set;
• said second member of said second gear set being continuously connected with ground;
• 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;
• and
• first, second, third, fourth and fifth torque transfer devices for selectively interconnecting said members of said first or second gear sets with said input member, with other members of said planetary gear sets, or with ground, said first, second, third, fourth and fifth torque transfer devices being engageable singly or in pairs to provide an electrically variable transmission with a continuously variable range of speed ratios and at least three fixed forward speed ratios between said input member and said output member.

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;
• an interconnecting member continuously connecting said first member of said first planetary gear set with said first member of said second planetary gear set;
• said second member of said second gear set being continuously connected with ground;
• 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 a member of said first or second gear set with said input member;
• a second torque transfer device selectively connecting a member of said first or second gear set with said input member;
• a third torque transfer device selectively connecting a member of said first gear set with another member of said first or second gear set;
• a fourth torque transfer device connected in parallel with said first or second motor/generator for braking rotation thereof;
• and
• wherein said first, second, third and fourth torque transfer devices are engageable singly or in pairs to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.