7. 7. BOOM FLOATING BOOM FLOATING SYSTEM SYSTEM ARM CYLINDER BUCKET CYLINDER BOOM CYLINDER SWING MOTOR E PS ps1 ps2 T3 T1 T2 T4 Pi1 V2 T Boom safety lock valve TRAVEL MOTOR LC0 A2 PS T Boom floating cartridge valve B6 A B P T Terminal block (j, Boom down) Boom down control solenoid valve A1 A2 FRONT PUMP REAR PUMP PILOT PUMP HYDRAULIC TANK 480A3HC08 Smooth and convenient boom movement is accomplished by only arm control lever operation. The boom floating solenoid values are equipped in the rod and head of boom cylinder that are controlled to act as floating mode. Boom floating cartridge valve is active. So the hydraulic oil of head goes to tank, and floating is accomplished.
In the mode, boom down control solenoid valve is active so that boom down pilot pressure is cut. For more details, refer to page 5-13. 3-13 A5 pb5 ARM 1 pa5 B4 A4 pb4 pa4 A3 B3 pb3 B2 pa3 A2 pb2 OPTION BOOM 2 SWING DR3 pa2 B1 pc6 TRAVEL(LH A1 pb1 pa1 TRAVEL(RH) TRAVEL STRAIGHT pr1 P1 PSPT PP PA PH PS SWING TRAVEL( RH) TRAVEL(LH TRAVEL STRAIGHT A6 pb6 pa6 ) P3 P2