Kubota WSM STa-30, Workshop Manual

Page: 296 / 359

9-M18
ST
α
-30, ST
α
-35, WSM HYDRAULIC SYSTEM
■
Single Acting Valve (B
3
Outlet)
(When spool is moved RH (When Lifting))
When the spool (11) is moved, the PB port (17) is
closed. The pressured oil open the check valve (1) and
into the valve through P
3
port (14).
The pressured oil into the unload valve (8) through B
3
port (15) and PX port (4). The oil pressure push the
poppet (2) to open the B
3
outlet (3).
W1019283
(When spool is moved LH (When Lowering))
When the spool (11) is moved, the PB port (17) is
closed. The pressured oil open the check valve (1) and
into the valve through P
3
port (14).
The pressured oil into the unload valve (8) through A
3
port (13) and PY port (6), then push the pilot valve (5).
The pilot valve (5) also push the poppet (2) to open the
B
3
outlet (3).
The oil from the B
3
outlet (3) flow to PX port (4) and
return to transmission case through the B
3
port (15) and
T
2
port (16).
The oil from PY port (6) flow to the orifice (9) after
moved pilot valve and return to transmission case
through the T port (10).
This orifice (9) maintain the pressure, to be opening
the pilot valve (5).
W1019605
(1) Check Valve
(2) Poppet
(3) B
3
Outlet
(4) PX Port
(5) Pilot Valve
(6) PY Port
(7) Single Action Cylinder
(8) Unload Valve
(9) Orifice
(10) T Port
(11) Spool
(12) T
1
Port
(13) A
3
Port
(14) P
3
Port
(15) B
3
Port
(16) T
2
Port
(17) PB Port
(18) PB Outlet
(1) Check Valve
(2) Poppet
(3) B
3
Outlet
(4) PX Port
(5) Pilot Valve
(6) PY Port
(7) Single Action Cylinder
(8) Unload Valve
(9) Orifice
(10) T Port
(11) Spool
(12) T
1
Port
(13) A
3
Port
(14) P
3
Port
(15) B
3
Port
(16) T
2
Port
(17) PB Port
(18) PB Outlet
KiSC issued 11, 2006 A