Komatsu ecot3 PC300LC-8 Shop Manual page 125

10 Structure, function and maintenance standard
4. Variable Volume Valve
C1: To PC valve
P1: From self pressure reducing valve
T1: To tank
Function
q The variable volume valve stabilizes the EPC
valve's output pressure.
Operation
q Output pressure from EPC valve is conducted
to port (C) and as the result propulsion force of
piston (3) is increased by the load of spring (4).
q Piston (3) is pushed to the left, and volume of
port (C) is increased.
The propulsion force of piston (3) becomes
q
smaller than the load of spring (4).
q Piston (3) is pushed toward right, and volume
of port (C) is decreased.
PC300, 350-8
1. Plug
2. Block
3. Piston
4. Spring
SEN01993-00
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