A multi-speed automatic transmission for private cars or commercial
vehicles includes input and output shafts, two power paths, a double
planetary gear train, first and second brakes. The first power path has a
first speed ratio and includes first and second clutches. The second
power path has a second speed ratio, which is greater than the first
speed ratio and in the same direction, with third and fourth clutches.
The transmission has eight forward and two reverse speeds and is highly
flexible. In one embodiment, the transmission is reduced to six forward
and one reverse speed without the second clutch. In another embodiment,
the input and output shafts are aligned and the ratios are supplied
respectively by a planetary gear train and a direct drive. In another
embodiment, the input and output shafts are parallel and the ratios are
supplied respectively by two parallel gear trains including constant mesh
gears.