Komatsu PC500LC-10R Shop Manual page 183

10 STRUCTURE AND FUNCTION
P-Q DIAGRAM AND PC VALVE
1.
When pump pressure is low
Pump (1) swash plate angle becomes maximum and flow rate becomes maximum.
2.
Range A in P-Q diagram
Service piston (2) and follow up link (3) are mechanically connected.
As the swash plate angle decreases, follow up link (3) pushes back PC valve spool (4) to the center.
PC500LC-10R
CLSS
10-89