THEORY OF OPERATION - CONTINUED
HYDRAULIC SYSTEM - CONTINUED
Piston Pump (Implement).
Implements piston pump has variable displacement, load sensing, compensation for pressure, and compensation
for flow. This piston type pump has variable flow and pressure dependent on system demands sensed by pressure
and flow compensator valves and signal limiter valve. Implements piston pump pressure and flow compensator
valve is not shown.
Pressure and flow compensator valves on each pump are identical. This paragraph is applicable to pressure and
flow compensator valves for both pumps. When engine is OFF, there is no load sensing signal to pressure and flow
compensator valve. Margin spring pushes flow compensator spool completely right. Any pressure behind actuator
piston is vented to case drain across flow compensator spool.
When there is no pressure behind actuator piston, bias spring is able to hold swashplate at maximum angle.
When engine is started, drive shaft starts to rotate. Oil flows into piston bore from pump inlet. Oil is forced out of
pump outlet and into system as cylinder barrel assembly rotates.