Komatsu PC200-8M0 Shop Manual page 172

SEN06120-00
Arm regeneration circuit
When cylinder head pressure is higher than bottom pressure
1. Main pump
2. Arm valve spool
3. Pressure compensation valve
4. Suction safety valve
5. Suction valve
6. Check valve
7. LS shuttle valve
Function
The regeneration circuit installed between the cylinder head and cylinder bottom increases the oil flow-
q
ing to the cylinder bottom (pump discharge + regeneration flow) during arm IN operation in order to
accelerate the cylinder.
Operation
q When the cylinder head pressure is higher than the bottom pressure, part of pressurized oil (A) from the
cylinder head flows to drain circuit (B) through the notch of arm spool (2).
q The remaining oil flows to the regeneration circuit (C), opens check valve (6), and flows to the cylinder
bottom through circuit (D).
q Flow from regeneration circuit (C) merges into the oil from pump (1) in circuit (E).
30
10-402
402 Hydraulic system, Part 2
Functions and operation by valve
PC200, 200LC, 220, 220LC-8M0