Theory of Operation
planet sun gear is located between thrust washers (C
The swing gearbox (R) is a double reduction planetary
and G). Second planet gears (F) rotate around shafts
drive type gearbox. The swing motor is mounted on
in the second planet carrier (P). The second planet
the swing gearbox and encloses the top side of
carrier is connected to the output pinion (L) and this
gearbox. The output pinion (L) is in mesh with the
causes the output pinion to rotate.
swing gear. Swing motor rotational speed is reduced
by the double reduction planetary gear set.
The pinion rotates in two spherical roller bearings (N
and O). Downward movement of pinion is prevented
The first planet sun gear (D) is connected to motor
by a snap ring (H) seated against upper bearing.
output shaft and is located between a retaining ring
Upward movement is prevented by second sun pinion.
and thrust washer (C). The first planet gears (E) rotate
Oil seal (K) prevents oil from leaking out of swing
around roller bearings on shafts in the first planet
gearbox and keeps grease from coming in.
carrier (B). Rotation of the first planet carrier causes
the second planet sun gear (Q) to rotate. The second