Main Parts Function; Holding Valve (Manual Open Type) - Kubota KX080-3 Workshop Manual

WSM KX080-3 Mechanism
e. Main parts function

Holding valve (manual open type)

Main part's function
No. Name
(1) Poppet
(2) Spool
(3) Piston (1), Piston (2)
(4) Relief valve
To stop a leak between main relief valve and cylinder.
Equipped with load check function.
Activated over the stroke by the cylinder-actuated pilot pressure to
control the flow rate from cylinder to main relief valve.
To control the poppet openness when the pilot pressure rises too high.
To receive the pilot pressure and to activate the spool over the stroke.
Spool to be activated over the stroke by piston (1) for relief purpose.
To regulate maximum pressure at the cylinder port.
IV-M-114
Function
A port : From control valve
B port : To boom cylinder bottom side
IV Hydraulic System