Hyundai HX145LCR Manual page 63

Flow increasing function
643 654
Large diameter
chamber
As the pilot pressure Pi decreases, the pilot piston (643) moves to the left by the action of the
pilot spring (646) and causes lever 2 (613) to rotate around the fulcrum of point B. Since the pin
(897) is pressed against the large hole section (C) of lever 2 by the action of the return spring
(654) via the spool (652), pin (874), and feedback lever (611), the feedback lever rotates around
the fulcrum of point D as lever 2 rotates, and shifts the spool to the left. Port CL opens a way to
the tank port as the spool moves. This deprives the large diameter section of the servo piston of
pressure, and shifts the servo piston to the left by the discharge pressure P1 in the small
diameter section, resulting in an increase in the flow rate.
As the servo piston moves, point D also moves to the left, the feedback lever rotates around the
fulcrum of point C, and the spool moves to the right till the opening between the spool and sleeve
is closed.
651 652
P1 CL
Pi(From MCV)
C
Servo piston
D
2-11
613 646
B(E)
874
897
A
875
611
548
531
Small diameter
chamber
140Z92MP13