Komatsu PC200-8M0, Shop Manual

Page: 132 / 1254

SEN06119-00
10-401
20
PC200, 200LC, 220, 220LC-8M0
401 Hydraulic system, Part 1
Hydraulic pump
q
As the spring force is weakened, spool (3)
moves to the right, the connecting between
port (C) and port (D) is shut off and the pump
discharge pressure ports (B) and (C) are con-
nected.
q As a result, the pressure on port (C) rises and
the pressure on the large diameter end of the
piston also rises. Thus, the leftward move of
servo piston (9) is stopped.
q Servo piston (9) stop position (= Pump dis-
charge) is decided by the position where the
pushing force generated from the pressures
(PP1) and (PP2) applied to spool (3), the push-
ing force of the solenoid in PC-EPC valve gen-
erates and the pushing force of springs (4) and
(6) are balanced.