Bomag BW 156 D-3, Service Manual

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Service Training
BW 156/177 D-3/PD-3 - E 3 -
BW 178/179 D-3/PD-3
Vibration pump
Similar to the travel pump, the vibration pump is also a swash plate operated Sauer-Sundstrand axial
piston pump with variable displacement for operation in a closed hydraulic circuit.
The displacement of the pump is proportional to the engine speed and the chosen displacment.
When actuating the swash plate out of neutral position the displacement for the chosen travel direction
will increase from “0" to maximum displacement. Changing the swash plate position through neutral to
the opposite side will change the flow direction and the sense of rotation of the vibrator shaft.
All valves and safety elements for operation in a closed circuit are integrated in the pump.
Fig. 3 Vibration pump
1 Vibration pump
2 Charge pump
3 High pressure limitation
4 4/3-way solenoid valve
to the brake
from charge pump and
charging of travel pump
to charging
vibration pump