Planetary transmissions with three gear sets and a stationary interconnecting member

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 having six torque-transmitting mechanisms and two fixed interconnections. Also, one interconnecting member is continuously connected with the transmission housing. The powertrain includes an engine and torque converter that is not continuously connected to any of the planetary gear members and an output member that is continuously connected with at least one of the planetary gear members. The six torque-transmitting mechanisms provide interconnections between various gear members, the fixed interconnections, the input shaft, and the output shaft, and are operated in combinations of three to establish at least seven forward speed ratios and at least one reverse speed ratio.