Planetary Gear Set.
(1) Planetary range pack torque paths.
Since the input gear
train paths are identical in all situations, the torque paths
described in the following paragraphs all start at the range input
(2) Neutral (fig. A-1).
therefore, torque produced in the converter does not go beyond the
input gear and forward clutch housing.
(3) First range (fig. A-2).
The transmission must have the
forward and first clutches applied for this range.
When the first
clutch engages, it prevents the rear planetary ring gear from
turning. When engaged, the forward clutch locks the range input gear
and main shaft together so they rotate as a unit. The rear sun gear,
splined to the main shaft, rotates the rear planetary pinions splined
to the range output gear. With the rear ring gear held stationary by
the applied first clutch, and the rear sun rotating the pinions, the
rear planetary carrier must rotate within the ring gear and drive the
range output gear.