Komatsu PC500LC-10R Shop Manual page 246

COMPONENT PARTS OF HYDRAULIC SYSTEM
FUNCTION OF INTRODUCTION OF LS PRESSURE IN CONTROL VALVE
1: Main pump
2: Main spool
3: Pressure compensation valve
4: Valve
• The upstream pressure of pressure compensation valve (3) (spool meter-in downstream pressure) is intro-
duced as LS pressure into LS shuttle valve (7).
This pressure is connected to port (B) of the actuator through valve (4), and LS pressure ≒ Actuator load
•
pressure.
• Introduction hole (a) in main spool (2) is small in diameter and used as an orifice.
• LS pressure is used as source pressure for closing the unload valve and as operating pressure when the
pressure compensation valve is compensated.
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10 STRUCTURE AND FUNCTION
5: Check valve
6: LS circuit
7: LS shuttle valve
PC500LC-10R