Komatsu PC500LC-10R Shop Manual page 184

CLSS
PC valve spool (4) is balanced.
3.
Range A in P-Q diagram
The pump pressure increases further, and springs (6) are compressed.
PC valve spool (4) moves to the right, and pump pressure is transmitted to the large diameter side of piston
(2).
4.
Range B in P-Q diagram
As the pump pressure increases further and compressed spring (6) reaches to the stroke end, only spring
(5) is applied.
10-90
10 STRUCTURE AND FUNCTION
PC500LC-10R