3-26
3-26
3. COMBINED SWING AND ARM OPERATION
PS
(P4)
(P3)
N2
Pca
Dr3
P2c2
Ba
Aa
PAa
PBa
Bo
Ao
PAo
PBo
(Ck2)
Drb
PBb2
PSp
Dra
Bs
As
PAs
PBs
Dr4
Pns
Br
Ar
PAr
PBr
TRAVEL(RH)
SWING
BOOM 2
T1
Pa
P2
P1 P1g
P2g
R4
(PTb)
PS
PL1
Py
PBL
PAL
BL
AL
Px
P
PBb
PAb
Ab
Bb
P2c1
Dr3'
PBc
PAc
PAcs
Bc
Ac
PBa2
PAa2
Pcb
N1
OPTION
ARM 1
ARM 2
BUCKET
BOOM 1
TRAVEL(LH)
SH
HYDRAULIC TANK
TRAVEL MOTOR
SWING MOTOR
ARM
CYLINDER
BUCKET
CYLINDER
BOOM
CYLINDER
PILOT
PUMP
R3
PUMP
A1
PUMP
A2
380L3HC22
When the swing and arm functions are operated simultaneously, the swing spool and arm spools in
the main control valve are moved to the functional position by the pilot oil pressure from the remote
control valve.
The oil from the A1 pump flows into the swing motor through swing spool and the arm cylinder
through arm 1 spool.
The oil from the A2 pump flows into the arm cylinder through the arm 2 spool of the right control
valve. The upper structure swings and the arm is operated.
Refer to page 2-35 for the swing operation preference function.