Komatsu PC500LC-10R Shop Manual page 276

COMPONENT PARTS OF HYDRAULIC SYSTEM
When the arm "IN" operation is performed
1.
When the arm "IN" operation is performed, the pilot pressure from the PPC valve pushes the pilot piston
(2).
2.
The pressurized oil in the arm cylinder head flows to drain port (T) through orifice (a), chamber (b), and
orifice (c).
3.
Chamber (b) in the poppet is connected to drain port (T), and the pressure in chamber (b) decreases.
4.
When the pressure in chamber (b) decreases below the pressure in port (B), poppet (5) opens.
5.
When poppet (5) opens, the pressurized oil from port (B) flows to port (A), and then flows to the control
valve.
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10 STRUCTURE AND FUNCTION
PC500LC-10R
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