2-34
Bucket out operation
刯
During the bucket out operation, the pilot pressure enters through port PBc and transfers the
bucket spool in the left direction in figure. The pressurized oil entering through port P1 passes
through the main path (1) and flows through the bypass circuit (2), but the bypass circuit is shut
off due to transfer of the bucket spool. Therefore, the pressurized oil flows into the parallel circuit,
pushes open the check valve (511), and flows through the U-shaped path to the bucket spool
(304). Then, it flows through the periphery of the spool to port Bc and is supplied to the bucket
cylinder rod side (R).
On the other hand, the return oil from the bucket cylinder head side (H) enters through port Ac,
passes around the periphery of the spool, and returns to the hydraulic oil tank through the tank
port (T1).
Bc
Ac
PBc
PAcs
PAc
U-shaped
path
Parallel circuit
511
304
3607A2MC21
