Family of multi-speed planetary transmission mechanisms having four clutches and two brakes

摘要

The family of transmissions has a plurality of members that can be utilized in powertrains to provide at least seven forward speed ratios and one reverse speed ratio. The transmission family members include three planetary gear sets with two brakes, four clutches and three fixed interconnections. The powertrain includes an engine and torque converter that is continuously connected to at least one member of the planetary gear arrangement and an output member that is continuously connected with another of the planetary gear members. The two brakes and four clutches provide interconnections between various gear members and with the transmission housing, the input or output shaft, and the three fixed interconnections, and are operated in combinations of two to establish at least seven forward speed ratios and one reverse speed ratio.