Transmission mechanisms with three planetary gear sets

A family of transmissions wherein each family member comprises:

• an input shaft;
• an output shaft;
• first, second and third planetary gear sets each having first, second and third members;
• said input shaft being continuously interconnected with a member of said planetary gear sets, and said output shaft being continuously interconnected with another member of said planetary gear sets;
• a first interconnecting member continuously interconnecting said first member of said first planetary gear set with said first member of said second planetary gear set;
• a second interconnecting member continuously interconnecting said second member of said first planetary gear set with said second member of said second planetary gear set;
• a first torque-transmitting mechanism selectively interconnecting a member of said first planetary gear set with said input shaft, said output shaft or a member of said third planetary gear set;
• a second torque-transmitting mechanism selectively interconnecting a member of said second planetary gear set with said input shaft, said output shaft or a member of said third planetary gear set;
• a third torque-transmitting mechanism selectively interconnecting a member of said third planetary gear set with a member of said first or second planetary gear set;
• a fourth torque-transmitting mechanism selectively interconnecting a member of said first, second or third planetary gear set with a stationary member;
• a fifth torque-transmitting mechanism selectively interconnecting a member of said first, second or third planetary gear set with said stationary member;
• and
• a sixth torque-transmitting mechanism selectively interconnecting a member of said first, second or third planetary gear set with another member of said first or third planetary gear set, or with said stationary member;
• said torque-transmitting mechanisms being engaged in combinations of three to establish at least seven forward speed ratios and at least one reverse speed ratio between said input shaft and said output shaft.