Kubota WSM L3560, Workshop Manual

Page: 313 / 801

TRANSMISSION
L3560, L4060, L4760, L5060, L5460, L6060, WSM
3-M37
(Continued)
1. The swashplate on the motor side is changed to the Lo side (The lamp of the turtle lights up and the rabbit lamp
goes off).
2. At the same time, the swashplate on the pump side is inclined toward the speed increasing side (To achieve
smooth shift transmission).
3. Even when the position of the swashplate on the motor side is changed toward the Lo side but a balance between
the load and engine torque cannot be achieved, the ECU controls the proportional control valve so that the engine
torque and loads on the HST are balanced, activates the servo piston and moves the swashplate on the pump
side to the neutral side. As a result, the loads applied on the pump are decreased more and reduces the load on
the engine. This increases the engine speed and prevents an engine stall.
* When the pedal is kept at the same position, the load is decreased and engine speed is increased again. In this
state, signals are being continuously transmitted from the engine speed sensor to the ECU. Then the signals are sent
from the ECU to the proportional control valve and the Hi-Lo solenoid valve. (4) As a result, the swashplate on the
pump side returns to its original position (before speed reduction). (5) The position of the swashplate on the motor
side is also automatically changed toward the Hi side. (The pump and motor move in almost the same manner as
shown in the illustration 4.)
* When the Hi-Lo lever is manually set at
"Lo"
position, the setting is not automatically changed to the Hi side
even if the AUTO H-DS function is set to
"ON"
.
9Y1210824TRM0039US0
[I] Stage 9

Stall Guard on and the PTO is engaged
[Tractor Condition]
Stall-Guard:
ON
Hydro Dual Speed:
ON
PTO Switch:
ON
1. By the load of the PTO, the engine revolution number goes down.
2. When the engine revolution goes down, the ECU will send the message to return the Pump Swashplate to the
neutral position.
3. At the Stall Guard PLUS, compared with at the Stall Guard, the Pump Swashplate is set in such a way as to
quickly return to the neutral position.
4. On the other hand, when the engine revolution recovers, the Pump Swashplate is set in such a way as to slowly
return.
5. The setting is in such a way as the PTO work can be done at the engine revolution of 2000 or higher even when
the PTO load is applied at the maximum engine revolution. (At the time of depressing the pedal.)
6. Because the stable engine revolution has priority, the response-dial is not operable for adjustment.
9Y1210824TRM0040US0
[J] Stage 10

Throttle-up Switch
[Tractor Condition]
HST Pedal :
Forward
Position
Throttle-Up Switch :
"OFF"
→
"ON"
→
"OFF"
The throttle-up function works while the throttle-up switch is pushed. While holding down the throttle-up switch,
the engine revolution increases to the preset revolution. Based on a signal from the throttle-up switch, the main ECU
provides an arbitrarily preset engine revolution to the engine ECU. Signals are sent continuously from each sensor
to the ECU all the time. Simultaneously, in order to prevent sudden increase in traveling speed as the engine
revolution rises, the main ECU controls the proportional control valve so that the increase of engine revolution and
swashplate on the HST keeps well-balanced relation. Because the proportional control valve controls the oil supplied
from the regulator, the servo piston moved toward the neutral direction. As a result, the swashplate on the pump side
moves toward the neutral direction. The signal from the throttle-up switch stops when the throttle-up switch is
released.
This enables return of the engine speed to the speed set by the hand throttle lever.
* When the pedal is kept at the same position, the signals are sent from the main ECU to the proportional control
valve. Thereby, more oil is supplied from the regulator to the servo piston. As a result, the swashplate on the pump
side returns to its original position.
9Y1210824TRM0041US0
KiSC issued 03, 2016 A