jcb ROBOT 150, Service Manual

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T Tank
2 Loader Valve
2X Pressure Test Points
4 Check Valve (2 bar)
8 Drive Control Joystick
8a
Joystick Control Spool
8b Joystick Control Spool
8c Joystick Control Spool
8d Joystick Control Spool
8e Shuttle Valves
9 Pressure Reducing Solenoid Valve
10 Filter By-pass & Cooler Relief Valve
Hydraulics
9803/8500
Issue 1
TRANSMISSION OPERATION - FORWARD
When the joystick 8 is moved to select forward drive
spool 8b is operated allowing oil from pump P3 to
pass via shuttle valves 8e to the swash plate servos
on pumps P1 and P2 . The swash plates are tilted
causing flow to pass to the motors M1 and M2 and
the machine moves forward.
Return oil from the motors flows back into the main
pumps. Any excess oil from the pump casing is fed
back to tank via cooler
C .
Shuttle valves 8e prevent servo pressure from being
fed into other servo circuits.
Key
C Cooler
F1 Filter
P1
Main Pump
P2 Main Pump
P3 Auxiliary Gear Pump
Pa Charge Valve
Pb Pressure Relief Valve
Pc Pressure Relief Valve
Pd Pressure Relief Valve
Pe Pressure Relief Valve
M1 Right Hand Drive Motor
M2 Left Hand Drive Motor
S1 Suction Strainer
8 - 2
8 - 2
Descriptions
Section E
Section E
4
M1
P1
P2
M2
P3
8
T
S1
C
2X
F1
2X
10
2
Pa
Pb Pc
Pd Pe
8a 8b 8c 8d
8e
x y
9
z
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