8-M5
B1710 · B2110 · B2410 · B2710, WSM
HYDRAULIC SYSTEM
4. POSITION CONTROL VALVE
â– Neutral
Oil forced into the control valve through the P port
pushes open the unload poppet (5) and then returns to
the transmission case through the T
1 port.
Oil behind the unload poppet (5) returns to the
transmission case through the spool (4) and the T
3 port.
Since the poppet 2 (1) and poppet 1 (2) are closed, oil
in the hydraulic cylinder does not flow to the transmission
case. Thus, the implement remains at its fixed position.
W10136350
â– Lift
When the control lever is set to the LIFT position, the
spool (4) is move to the right.
The oil forced into the control valve through the P port
flows to the back of the unload poppet (5) to close it.
The oil pushes open the poppet 1 (2), and flows into
the hydraulic cylinder through the C port to lift the
implement.
W10137360
â– Down
When the control lever is moved to DOWN position,
the spool (5) is move to the left, and the poppet 2 (2) is
also move to the left by the lever (1).
Oil in the hydraulic cylinder is forced out to the
transmission case through the T
2 port by the weight of
the implement, causing the implement to lower.
Oil forced into the control valve through the P port
pushes open the unload poppet (6) and returns to the
transmission case through the T
1 port.
W10138410
(1) Poppet 2
(2) Poppet 1
(3) Plunger
(4) Spool
(5) Unload Poppet
P : Pump Port
C : Cylinder Port
T
1, T2, T3 : Tank Port
(1) Poppet 2
(2) Poppet 1
(3) Plunger
(4) Spool
(5) Unload Poppet
P : Pump Port
C : Cylinder Port
T
1, T2, T3 : Tank Port
(1) Lever
(2) Poppet 2
(3) Poppet 1
(4) Plunger
(5) Spool
(6) Unload Poppet
P : Pump Port
C : Cylinder Port
T
1, T2, T3 : Tank Port