Hitachi ZW180 Technical Manual page 357

Traveling Straight with the Same Road Resis-
tances to Left and Right Tires
As the differential pinion gear and the left and right
pinion gears rotate solidly, the driving forces of the
left and right tires are the same similarly to TPD.
Traveling on Soft Ground (Different Road Resis-
tances to Left and Right Tires)
Driving force is transmitted to the case, pressure ring
and spider through the ring gear. At this time, the
spider having the cam construction pushes the
pressure ring with thrust force (P). The clutch disc is
geared with the case through the pressure ring. As
the side gears fitted to the clutch disc by spline rotate
solidly with the case, the left and right gears rotate at
the same speed.
Like this, the left and right axle shafts fitted to the
side gears by spline tend to rotate solidly with the
case, and the differential movement restriction works.
In case the driving force provided for the slipping tire
is larger than the road resistance, part of the torque
of the slipping tire is added to the tire contacting
ground by the differential movement restriction (be-
cause of the same speed of the left and right tires),
and the tire contacting ground is provided with more
torque.
Until the difference of the resistances between the
left and right tires exceeds certain value (until the
clutch disc begins to slip), the left and right gears
solidly rotate at a constant speed. On such soft
ground, the driving force increases by 1.5 times the
value for TPD if LSD is provided.
COMPONENT OPERATION / Axle
T3-10-9
P P
Clutch Disc
Pressure Plate
Spider
Pressure Ring
T4GB-03-10-004