Power Train
Systems Operation
7
Power Transfer Group
Power Transfer Group
(1) Bevel gear (2) Differential case (3) Helical gear (4) Spiral hypoid pinion (5) Input Gear (6) Drive Motor Shaft
1
2
3
5
6
4
The power transfer group is mounted under the
frame in the front of the lift truck. ItÕs a double reduc-
tion unit with the final reduction through spiral hypoid
pinion (4) and bevel gear (1).
Power for the transfer group comes from the electric
drive motor through the input gear connected with
the Drive Motor Shaft (6) through the spline . The
input gear (5) turns helical gear (3) that is mounted
on the shaft of the hypoid pinion (4).
The hypoid pinion is engaged with bevel gear (1)
which is mounted to differential case (2).
Differential case (2) has two pinion gears that are
engaged with two side gears. The side gears turn the
axle shafts.
The power transfer group is used to send the power
from the electric drive motor to the wheels. When
one wheel turns slower than the other, the power
transfer group lets the inside wheel stop or turn slow-
er in relation to the outside wheel.
When the truck is moving straight in a forward direc-
tion with the same traction under each wheel, there is
equal torque on each axle. This holds (stops) differ-
ential pinion gears which give the same effect as if
both wheels were on the same axle. During a turn,
the force (traction) that is on the drive wheels is dif-
ferent. These different forces are also felt on opposite
sides of the power transfer group and cause differen-
tial pinion gears to turn. The rotation of differential
pinion gears stops or slows the inside wheel and lets
the outside wheel go faster. This moves the machine
through a turn under full power.
The power transfer group gets lubrication from oil
thrown about inside the housing, by the rotating
gears.
