GROUP 5 COMBINED OPERATION 1. OUTLINE ARM CYLINDER BUCKET CYLINDER BOOM CYLINDER TRAVEL MOTOR P5 P4 Pi2 Rs MU Pi1 Pn1 Pn2 SWING MOTOR PBa PAb1 P02 P04 PDb2 A2 PUMP A1 PUMP PILOT PUMP HYDRAULIC TANK 330S3HC17 The oil from the A1 and A2 pump flows through the neutral oil passage, bypass oil passage and confluence oil passage in the main control valve. Then the oil goes to each actuator and operates them. Check valves and orifices are located on these oil passage in the main control valve. These control the oil from the main pumps so as to correspond to the operation of each actuator and smooth the combined operation.
STRAIGHT TRAVEL SPOOL This straight travel spool for straight travel is provided in the main control valve. If any actuator is operated when traveling, the straight travel spool is pushed to the right by the pilot oil pressure. Consequently, the left and right travel oil supply passage are connected, and equivalent amount of oil flows into the left and right travel motors. This keeps the straight travel.
3-24 BC1 NRV2 Cck BC2 NRV1 Cco CoR DoR AkR LCk1 LCk2 ON LCo CaR DaR BUCKET BbkR 1 LCa LCa2 ARM2 PAa2 DR6 Ccb M2 SWING P/R LCar LCbk BbR ARM REGEN P02 Abk PBrc PAbk DR4 Cs Ds PCs PDs DR5 SWIN P03 DR3 Ctl Dtl PCtl PDtl SH Patt ( TR RIG AVH PS DR1 P01 PtrPS STRAIGHT TRAVEL SPOOL Cs Ds PCs PDs DR5 SWIN G LCs AbR LCb CRb BOOM1 BtR AtR T) EL (LEFT) TRAVEL TS MRV