| 摘要 |
A multi-speed planetary gear including a planet gear carrier connected to one of the primary or secondary shafts, planet gears mounted thereon, each including at least two gear surfaces at different diameters. At least three annular gears, i.e. sun or ring gears, engage said gear surfaces. One of these is a drive annular gear engaged with the primary or secondary shaft other than the one to which the planet carrier is engaged. Each of the other annular gears, i.e. other than the drive annular gear, is connectable against rotation relative to the casing by a friction brake and a servo-motor means, which servo-motor means are mounted non-rotatively relative to the casing. The force of at least one servo-motor, preferably the one effecting a direct drive connection is transmitted across axial thrust bearings through a slidable annular gear and a lever means. The remaining annular gears are selectively connectable to the casing for various types of drive including different ratio forward drives and reverse drive. |
