Planetary transmissions with three gear sets and a stationary fixed interconnection

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