Sakai R2-4, Shop Manual

Page: 55 / 234

4-002
HYDRAULIC SYSTEMS
Valves
DESCRIPTION SYMBOL
Check valve
Manual shut off (On-Off)
Pressure relief
Flow control, adjustable
Valve symbols:
The basic valve symbol
one or more squares
with lines representing
flow paths and flow con-
ditions between ports.
Multiple squares indicate
a valve with as many dis-
tinct positions there are
squares providing various
flow path options for the
fluid.
The multiple square
moves to represent how
flow paths change when
the valving element is
shifted within the compo-
nent.
Valves with infinite posi-
tioning between certain
limits are symbolized
with lines parallel to the
squares.
Methods of Operation
DESCRIPTION SYMBOL
Spring
Manual
Pressure compensated
Reversing motor
Pilot pressure:
Internal supply
Remote supply
Solenoid:
Single winding
Two windings operating
in opposite directions.
Pilot directional valve is
actuated by the solenoid.