Komatsu PC200 walking PPC reciprocating valve:

1, when the walking control rod in the middle
Komatsu PC200 walking PPC reciprocating valve function:
In climbing steep slope, lifting the boom, with the bucket rod excavation, unloading, bucket excavation or operation dump, through the use of walking PPC valve pilot pressure control arm, bucket rod and bucket valve column stroke and adjust to the flow of each cylinder.
When controlling the stroke of the boom, bucket rod and/or bucket, the pilot pressure of the walking PPC valve passes through the oil circuit inside the control valve to drive the system.
Komatsu PC200 walking PPC reciprocating valve operation:
stroke adjustment signal chamber (a) of oil from the piston (3) and (4) of the throttle (5) and (6) discharged into the walking spring box and walking PPC valve.
When operated to lift into the action arm (or bucket rod excavation, unloading, bucket excavation, tipping), the valve post (1) moves to the left until it makes contact with the end face of the box spring (2)(sto).
When walking
Komatsu PC200 walking PPC reciprocating valve operation:
If the right walk control lever is set in the backward (or forward) direction, the pilot pressure from the PPC valve to the left (or right) pressure valve column (7).
Valve post (7) pushes the piston (3) to close the throttling port (5) and to close the stroke regulating signal chamber (a) and the discharge path of the walking PPC valve.
At this point, the right backward (or forward) walk lever is set and the PPC pressure is applied to the left end of the piston (8) through the orifice (6) of the piston (4) and pushes the piston (8) to the right.
The valve post (1) moves to the left when it is operated to lift the action arm (or the bucket rod is withdrawn, unloaded, the bucket is excavated, unloaded). The stroke of the
valve post is limited to (stl) to limit the amount of right movement of the piston (8).
This valve prevents the oil at the bottom of the boom cylinder from leaking from the valve post (1) when there is no operating boom control lever and prevents the boom from falling under its own weight.