Multi-Speed Transmission

摘要

A family of transmission gearing arrangements produces at least nine forward speed ratios and one reverse speed ratio by selective engagement of three shift elements in various combinations. Each disclosed transmission includes four planetary gear sets, three brakes, and either three or four clutches. One embodiment produces twelve forward speed ratios and two reverse speed ratios. Another embodiment produces thirteen forward speed ratios.

主权项

1. A transmission comprising:
an input shaft, an output shaft, and first, second, third, fourth, fifth, and sixth shafts; a first gearing arrangement configured to fixedly impose a linear speed relationship among the first shaft, the second shaft, the third shaft, and the fourth shaft; a second gearing arrangement configured to fixedly impose a linear speed relationship among the third shaft, the input shaft, and the fifth shaft; a third gearing arrangement configured to fixedly impose a linear speed relationship among the third shaft, the output shaft, and the sixth shaft; a first clutch configured to selectively couple the output shaft to the fifth shaft; a second clutch configured to selectively couple the input shaft to the first shaft; a first brake configured to selectively hold the sixth shaft against rotation; a second brake configured to selectively hold the first shaft against rotation; and a third brake configured to selectively hold the second shaft against rotation.