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31 - 3
Section E
Hydraulics
9803/6400
Section E
31 - 3
Issue 2*
Control Valve JS200/JS240
Operation
(continued)
Individual Operation
1. Travel Spool Switch (Refer to Fig. 1,3,4).
When the P
bl1
(P
al1
) is pressurised and the 5-spool travel spool is selected (Fig. 4), the neutral passage
A
is closed and
downward flow is cut off, so the oil delivered from the P
L
port flows from the 5-spool neutral passage
A
past the sleeve (M) into
passage I to the spool neck, to the passage
K
(passage J) and flows to the cylinder port B
Li
(A
Li
).
When the P
bR1
(P
ar1
) port is pressurised and the 4-spool travel spool is selected to neutral, passage
a
is closed and downward
flow is cut off, so the oil delivered from the P
R
port flows from the 4-spool neutral passage
a
to the sleeve K(N), passage
f
to the
spool neck, passage
g
(passage
h
) and flows to the cylinder port B
RI
(A
RI
).
The return oil from the cylinder port flows through the spool neck and is released to the tank.
When one side of the 4-spool (5-spool) travel spool is selected (Fig. 3,4), the signal land (K) (L) is closed but the oil entering
from the signal port P
p
flows through the restriction (I) (J) passage, land (K) (or restriction (I) (J) passage (f) (g) (h) then land (L)
and is connected with the tank passage so the signal passage (f) pressure does not rise and the travel linearity spool maintains
its indicated position due to spring force. (Fig.1)
When the above operations (4,5 spool simultaneous, or separate) are made, flow to the tank passage of the signal passage (b)
is cut off so the P
t
port pressure rises.
Boom Spool Selection
2. Up (II speed confluence) (Refer to Fig. 1,3,5,8,).
When pilot port P
aR2
is pressurised and the boom I spool is selected, the 4-spool neutral passage a is closed and the oil
delivered from the P
R
port flows from the 4-spool parallel passage
b
and pushes up the load check valve (O), flowing through
passage
i
spool neck and passage
K
and pushes open the lock valve poppet (P) and flows into A
R2
port.
When P
aR2
is pressurised (Fig. 1,8) part of the oil flows from the outer passage through the P
2
port and flows to the shuttle (Q)
passage z x, and from the P
3
port flows through the outer passage again and pressurises P
4
port and selects the boom II spool.
At this time, due to the spool being selected (Fig. 8) and the flow to the neutral passage A from passage D being cut off, the oil
delivered from P
L
flows through passage B, pushes open load check valve (R) and flows through passage C H L1 (Fig. 3) L
2
(Fig. 5), converging with passage
K
from 4-spool passage
m
.
The return oil from cylinder port B
R2
flows though passage
j
and through boom
I
spool neck and is released to the tank
passage. (Fig. 5)
3. Lower (Refer to Fig. 6, 14).
When the pilot port P
bR2
is pressurised and the boom I spool is selected (Fig. 6), the 4-spool neutral passage a is cut off and
the oil delivered from the P
R
port flows through the 4-spool parallel passage b, pushes open the load check valve (O) and flows
through passage
i j
from cylinder port B
R2
.
The return oil from cylinder port A
R2
flows through the lock valve poppet (
P
) and, through passage K, flows to the spool neck
and is released to the tank passage.
*
Summary of Contents for JS 200 Series
Page 57: ...9 1 Section 3 Routine Maintenance 9803 6400 Section 3 9 1 Issue 2 Component Location Diagram...
Page 113: ......
Page 137: ...5 3 Section C Electrics 9803 6400 Section C 5 3 Issue 2 Pump Control FLOW CHART...
Page 201: ...10 7 Section C Electrics 9803 6400 Section C 10 7 Issue 1 CAPs II Diagnostic system K C...
Page 215: ...Section E Section E Hydraulics 9803 6400 Issue 2 3 2 3 2 Schematics...
Page 217: ...Section E Section E 9803 6400 Issue 2 3 3 3 3 Hydraulics Schematics...
Page 218: ...3 5 Section E Hydraulics 9803 6400 Section E 3 5 Issue 1 Schematics Shuttle Block JS200 JS240...
Page 232: ...10 1 Section E Hydraulics 9803 6400 Section E 10 1 Issue 1 Hydraulic Pump JS200 JS240...
Page 233: ...10 2 Section E Hydraulics 9803 6400 Section E 10 2 Issue 1 Hydraulic Pump JS200 JS240...
Page 234: ...10 3 Section E Hydraulics 9803 6400 Section E 10 3 Issue 1 Hydraulic Pump JS200 JS240...
Page 263: ...30 2 Section E Hydraulics 9803 6400 Section E 30 2 Issue 1 Control Valve JS200 JS240...
Page 264: ...30 3 Section E Hydraulics 9803 6400 Section E 30 3 Issue 1 Control Valve JS200 JS240...
Page 265: ...30 4 Section E Hydraulics 9803 6400 Section E 30 4 Issue 1 Control Valve JS200 JS240...
Page 266: ...30 5 Section E Hydraulics 9803 6400 Section E 30 5 Issue 1 Control Valve JS200 JS240...
Page 267: ...30 6 Section E Hydraulics 9803 6400 Section E 30 6 Issue 1 Control Valve JS200 JS240...
Page 268: ...30 7 Section E Hydraulics 9803 6400 Section E 30 7 Issue 1 Control Valve JS200 JS240...
Page 327: ...51 12 Section E Hydraulics 9803 6400 Section E 51 12 Issue 1 Solenoid Valve 8 spool...
Page 328: ...55 1 Schematic Section E Hydraulics 9803 6400 Section E 55 1 Issue 1 Shuttle Valve...
Page 330: ...55 3 Schematic Section E Hydraulics 9803 6400 Section E 55 3 Issue 1 Cushion Valves...
Page 481: ...7 15 Section F Transmission 9803 6400 Section F 7 15 Issue 2 Motor...
Page 482: ...7 16 Section F Transmission 9803 6400 Section F 7 16 Issue 1 Motor...