Bomag BW 156 D-3 Service Manual page 112

During the suction stroke the oil is drawn into the piston chamber, i.e. the charge pressure forces it into
the piston chamber. On the opposite side the piston presses the oil out into the high pressure side of
he closed circuit.
Control
The electro-hydraulic displacement control (remote control) converts the electric input signal to a load
controlling output signal. Since the pump is not equipped with a proportional control, but a 12 Volt
solenoid valve, the pump is always actuated to one of the two end stop positions.
High pressure relief valves
As a measure to protect the closed vibration circuit against to high pressures the vibration pump is fitted
with pressure relief valves.
Fig. 6 Pressure relief valve
1 From the charge pump
2 Closed circuit
3 High pressure relief valve with
integrated boost check valve
BW 156/177 D-3/PD-3
BW 178/179 D-3/PD-3
1
2
3
Service Training
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