Komatsu PC500LC-10R Shop Manual page 356

COMPONENT PARTS OF TRAVEL SYSTEM
OPERATION OF COUNTERBALANCE VALVE AND CHECK VALVE OF TRAVEL
MOTOR
During normal travel (flat ground and uphill ground)
1.
The pressurized oil from the control valve is supplied to
port (PA) when the travel lever is operated.
2.
The pressurized oil pushes open the check valve (13A),
and flows from motor inlet port (MA) to motor outlet port
(MB).
3.
The pressure on the supply side increases since the motor
outlet side is closed by the check valve (13B) and spool
(14).
4.
The pressurized oil on the supply side flows to chamber
(S1) through orifice (E1) of spool (14) and orifice (E2).
5.
When the pressure in chamber (S1) increases higher than
the reaction force of the spool selector pressure, spool
(14) is pushed to the right.
6.
The motor outlet port (MB) and port (PB) are connected to
the outlet passage. The motor outlet side opens, and the
motor is operated.
10-262
10 STRUCTURE AND FUNCTION
PC500LC-10R
AEP20517
AEP20518