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C. General description
system, preprogrammed/preprogramed automatic
functions of Powershift--- for different driving conditions
and power shuttle.
The digital display panel in the tractor keeps the driver
informed by displaying the status of different operations,
e.g. driving direction, which of the Powershift--- gears is
engaged, chosen automatic operations, outdoor
temperature, it also shows when the PTO is engaged and
indicates any possible error function with a service code.
The main gearbox has 12 forward speeds and 12
reverse speeds. The 3---step Powershift gear on
tractors give 36 gears forward and 36 reverse gears.
Shafts and gearwheels in the gearbox are pressure
lubricated.
C 4.4.
Rear axle
The rear axle is fitted directly to the gearbox. The
differential lock in the rear axle is electro---hydraulically
controlled. When it is engaged, pressurized oil is pumped
to the multi---disc differential clutch, and this causes the
differential to lock. When the brake pedal is pressed the
differential lock is automatically disengaged. An indicator
lamp on the instrument panel lights when the differential
lock is engaged.
Final drives are of the planetary gear type. From the
planetary gears power is transmitted to the rear wheels.
C 4.5.
Powered front axle
T C10
The powered front axle is driven from the gearbox bevel
pinion shaft front end.
Front wheel drive can be engaged and disengaged
electro---hydraulically. When 4WD is engaged the springs
force the discs together and four---wheel drive engages.
Consequently the 4WD is always engaged when the
engine is stopped (multi---disc clutch not pressurized).
In addition when braking, the front---wheel drive always
engages in order to provide the braking function for the
front wheels.
The electro hydraulic front axle differential lock operates in
conjunction with the rear axle lock, giving better traction
for the front wheels even on slippery surfaces.
An suspensioned front axle is also available as extra
equipment on all models.
C 4.6.
Power take---off
T C11
The PTO rotating speed is selected with a lever, which can
select either 540 r/min or 1000 r/min nominal rotating
speed. Engagement and disengagement is electro---
hydraulically through a different button. It is also possible
as alternative equipment to have a 540E (750) r/min PTO.
The control unit of the gearbox also controls the function
of the power take---off. This makes the power take---off
engagement smooth without loading the implement. The
display shows a symbol if the power take---off shaft is
rotating.
The tractor T191LS is a Sigma Power model, whose prin-
cipal function is, that the tractor power take---off has been
constructed to transfer larger output and torque than the
tractor driving transmission. The engine has three different
output and torque areas. The power ranges are controlled
automatically through an electric system.
The power take---off shaft is easy to change. As standard
the tractor is provided with a 6---spline shaft and as extra
equipment shafts with 21---, 20---, 6--- or 8 splines for
greater torque can be fitted on the tractor.
As optional equipment a ground speed PTO is also
available.
The front power take---off is available as optional
equipment (with front linkage). The front PTO shaft
nominal rotating speed is 1000 r/min and the shaft is
6---spline.
