Komatsu PC600LC-7 Manual page 78

STRUCTURE, FUNCTION AND MAINTENANCE STANDARD
2) When command current value from controller is large in A and E mode
Operation
• The command current sent from the controller
moves push pin (9), which moves spool (2).
Spool (2) stops at a position where it is balanced
with spring (1). At this time, since the command
current and the force of push pin (9) are large,
spool (2) is balanced on the upper side.
10-46
HYDRAULIC PUMP (PISTON PUMP)
• As a result, the oil flow from the control pump is
reduced between ports "a" and "b" and the open
areas of port "b" and port "c" (drain port) in-
crease. Then, TVC valve output pressure PE
and signal pressure PECN lower, thus the pump
discharge amount decreases.
PC600, 600LC-7