
EPICYCLIC GEARBOXES 265
Manual low gear
When this is selected the power flow through the
gearset is exactly the same as in automatic low gear,
except that the rear band is applied to provide engine
braking on vehicle overrun (Figure 16.6a). This feature
is otherwise absent in automatic low gear, because the
one-way clutch free-wheels on the overrun in the in-
terests of smooth gear changes.
Intermediate gear
The rear clutch remains engaged so that drive from the
input shaft is again transmitted to the annulus gear of
the front train. In this case, however, rotation of the
annulus gear causes the planet pinions to walk around
the common sun gear ...