Planetary transmissions having three non-continuously interconnected gear sets

摘要

The family of transmissions has a plurality of members that can be utilized in powertrains to provide at least eight forward speed ratios and one reverse speed ratio. The transmission family members include three planetary gear sets having seven torque-transmitting mechanisms. None of the members of the planetary gear sets are continuously grounded or continuously connected with any other member of the planetary gear sets. The powertrain includes an engine and torque converter that is continuously connected to at least one of the planetary gear members and an output member that is continuously connected with another one of the planetary gear members. The seven torque-transmitting mechanisms provide interconnections between various gear members and the transmission housing, and are operated in combinations of five to establish at least eight forward speed ratios and at least one reverse speed ratio.