4. COMBINED SWING AND BUCKET OPERATION ARM CYLINDER BUCKET CYLINDER BOOM CYLINDER P5 P4 Pi2 Rs MU Pi1 Pn1 Pn2 TRAVEL MOTOR SWING MOTOR PBa P02 P04 PAb1 PDb2 A2 PUMP A1 PUMP PILOT PUMP HYDRAULIC TANK 330S3HC20 When the swing and bucket functions are operated, simultaneously the swing spool and bucket spool 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 the swing spool in the left control valve. The oil from the A2 pump flows into the bucket cylinder through the bucket spool in the right control valve. The upper structure swings and the bucket is operated.
3-27 BC1 N RV2 Cck R9 Co 05 Do Co Do OPTION Ca Da BC2 NRV1 Cco CoR AkR LCk1 LCk2 DoR LCo CaR DaR BUCKET BbkR R7 CRa aL ARM1 LCa LCa2 ARM2 PAa2 DR6 sp b2 BOOM2 Ccb SWING P/R LCar LCbk BbR ARM REGEN P02 Abk PBrc PAbk DR4 Cs Ds PCs PDs DR5 SWING P03 DR3 Ctl Dtl PCtl PDtl SH Patt ( TR RIG AVH ET L) PS DR1 P01 PtrPS TS P P D Cs Ds Cs Ds R5 SWING LCs AbR LCb CRb BOOM1 03 R3 tl tl Ctl Dtl att (RIGHT) TRAVEL R1 BtR AtR (LEFT) TRAVEL MRV