3 - 22
Attachment - Boom Up
Pressurised oil from port
A2
(rear pump) enters port
4P
of the control valve. Pressurised oil from port
A1
(front
pump) enters port
5P
of the control valve.
When operating boom up with the hand controls, the
pilot pressurised oil flows through the cushion valve into
port
4Pb3
of the control valve and switches boom spool
(1)
and boom spool
(2)
.
Pressurised oil flows into port
4P
, through the load
holding valve and into the boom ram instigating boom
up operation. Pressurised oil entering port
5P
merges
with the pressurised oil from the boom spool
(1)
inside
the control valve and high speed can be achieved.
Section E
Hydraulics
9803/6020
Section E
3 - 22
Issue 1
Schematics
A
Pressure Line
B
Return Line
C
Pilot Line
D
Control Valve
E
Boom Cylinder
F
Boom (1)
G
Boom (2)
H
Cushion Valve
J
Pump
Summary of Contents for JS70
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