Patent ID: 7311635
Filing Date: 2007-12-25
Classification: F16H

Abstract:
1. A multi-speed transmission comprising: an input shaft; an output shaft; first, second, third and fourth planetary gear sets each having a first, a second and a third member; 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 first member of said third planetary gear set with said first member of said fourth planetary gear set; a third interconnecting member continuously interconnecting said second member of said third planetary gear set with said second member of said fourth planetary gear set; said second member of said second planetary gear set being continuously connected with a stationary member; said input shaft being continuously connected with said a member of said planetary gear sets and said output shaft being continuously connected with another member of said planetary gear sets; and six torque-transmitting mechanisms, operable for selectively interconnecting said members of said planetary gear sets with said input shaft, with said stationary member or with other members of said planetary gear sets, said six torque-transmitting mechanisms being engaged in combinations of two to establish seven forward speed ratios and three reverse speed ratios between said input shaft and said output shaft; wherein any of said members of said planetary gear sets rotating during said seven forward speed ratios rotate in one direction.