Hyundai HX130LCR Manual page 80

7) ARM OPERATION
(1) ARM IN OPERATION
During arm in operation, the pilot secondary pressure from the RCV is supplied to the port Pc40
of spring opposite side and shifts arm 1 spool in the right direction.
The bypass passage is shut off by the movement of the arm 1 spool and the hydraulic oil from the
pump A1 flows into the arm cylinder head side through P2 parallel passage, the load check valve,
bridge passage and the port C4.
At same time, the pilot secondary pressure from the RCV is supplied to the port Pb3 of spring
opposite side and shifts arm 2 spool in the right direction. The bypass passage is shut off by the
movement of the arm 2 spool and the hydraulic fluid from the pump A2 flows into the arm
summation passage through P1 parallel passage, the check valve, the arm 2 spool and the boom
2 spool. Then it entered the arm cylinder head side with hydraulic fluid from arm 1 spool.
Load check
P2 Parallel passage
Piston C
Selector spool
Pc40
Arm regeneration
cut pilot pressure
Pb4
Pc42
Arm in
pilot pressure
Arm regeneration
& breaker spool
Arm in pilot
pressure
Pb3
From RCV
C4
Arm summation passage
P1 Bypass passage
P1 Bypass passage
2-36
Arm summation passage
Arm 1 spool
D4
Boom 2 spool
Arm 2 spool
P1 Parallel passage
P1 Parallel passage
Tank passage
P2 Bypass passage
125LCR2MC21