Patent ID: 6908408
Filing Date: 2005-06-21
Classification: F16H

Abstract:
1. A multiple-speed ratio automatic transmission for an automotive vehicle, comprising: an input; an output; a planetary gear system comprising first, second and third planetary gear units, each gear unit having a sun gear, a ring gear, planet pinions meshing with the sun gear and the ring gear, and a carrier rotatably supporting the planet pinions, the first gear unit being one of a simple planatary gear unit having first planet pinions, and a compound planatary gear unit having second planet pinions meshing with the sun gear of the first gear unit and third planet pinions meshing with the ring gear of the first gear unit and with the second planet pinions, the input being driveably connected to the sun gear of the first gear unit, the output being driveably connected to the carrier of the third gear unit, the ring gear of the third gear unit being driveably connected to the carrier of the second gear unit, one of the carrier of the first gear unit and the ring gear of the first gear unit being non-releasably secured against rotation, the sun gear of the second gear unit being driveably connected to the sun gear of the third gear unit; a first brake for holding against rotation and releasing the ring gear of the second gear unit; a second brake for holding against rotation and releasing the carrier of the second gear unit and ring gear of the third gear unit; a first clutch for driveably connecting and disconnecting the input and the sun gears of the second and third gear units; a second clutch for driveably connecting and disconnecting the input and carrier of the second gear unit; and a third clutch for releasably driveably connecting the other of the carrier of the first gear unit and the ring gear of the first gear unit to the ring gear of the second gear unit.