Komatsu Galeo BR380JG-1E0 Shop Manual page 134

SEN01352-00
Pressure compensation valve
1. During independent operation and under maximum load pressure
(If the load pressure is higher than other work equipment during a combined operation)
1. Hydraulic pump
2. Valve
3. Shuttle valve
Function
Pressure compensation valve works as the
q
load check valve.
If the pump pressure (LS pressure) is lower
q
than the load at port (c), shuttle valve (3) in
pressure compensation valve piston (4) inter-
connects spring chamber (E) and port (C).
The force of spring (5) operates piston (4) and
q
valve (2) to the closing direction.
Integrated pressure compensation valve
High stress may occur when valve (2) collides
q
with valve chamber seat portion (C) if a high
peak pressure is generated in the actuator cir-
cuit or repetitive peak pressure occurs continu-
ously (example: when using the breaker).
To prevent this, a pressure compensation
q
valve with integrated valve (2) and piston (4) is
used.
With the present machine, this device is adopted
q
for travel valve.
24
10 Structure, function and maintenance standard
4. Piston
5. Spring
6. LS shuttle valve
As principle, port (C) and spring chamber (E)
q
are not interconnected in an integrated pres-
sure compensation valve.
If high peak pressure is generated at port (C),
q
valve (7) does not collide with the valve cham-
ber.
1
BR380JG-1E0