Komatsu Utility SK714-5, Shop Manual

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10-30 SK714-5 SK815-5 SK815-5 turbo
FUNCTION
• Port A is connected to the charge circuit.
Port B is connected to the tank drain circuit.
The pressurized oil fills port C through orifice a in valve ( 2A ).
Poppet ( 2D ) is in tight contact with valve seat ( 2C )
•
If abnormal pressure is generated in the circuit or the shuttle valve of HST motor is at neutral and the oil pressure at
ports A and C reaches the pressure set by spring ( 2E ), poppet ( 2D ) is pushed to direction, and oil at C is relieved
to port B and pressure of the oil at C reduce.
•
When the pressure of the oil at port C goes down, a differential pressure is occured between ports A and C because
of orifice a in valve ( 2A ).
Valve ( 2A ) is pushed to direction by oil pressure at port A , and oil at port A is relieved to port B .
In this way, the pressure in the charge circuit is prevented from going any higher.
RKS00010
1
2
A
2
C
2
D
a
C
A
2
E
B
RKS00020
A
2
D
2
E
2
A
B
C
RKS00030
B
A
2
A
a
C
STRUCTURE AND FUNCTION
HYDRAULIC PUMP