Theory of Operation
ARM REGENERATIVE VALVE OPERATION
engine and pump controller sends an electrical signal
The arm regenerative valve (H) is used to improve arm
to the arm regenerative solenoid valve (D) to energizes
controllability and prevent arm cylinder (A) cavitation
the coil. The solenoid valve then sends a pressure
during arm IN operation by combining the return oil
signal to the arm regenerative valve spool (E) to shift it
from arm cylinder rod end with the pump supply oil to
blocking the passage to return. The return oil from the
the arm cylinder head end.
rod end of arm cylinder now flows through the arm
regenerative circuit check valve (C) and then to the
Under the following operating conditions: low rear
head end of arm cylinder with the pump supply oil.
pump delivery pressure, high pilot pressure to the pilot
Return oil not used flows through the orifice (J) to the
cap for arm in, and boom up actuated, gravity can pull
the arm in faster than the pump can supply oil to the
arm cylinder head end. The operating conditions are
There are five check valves located in the passages to
sensed by the rear pump pressure sensor (I), arm in
the arm I valve to prevent back flow through the
pressure sensor (K), and boom up pressure switch (L).
control valve. For arm in function, return and supply oil
The pressure switch and sensors send electrical
flows through the arm I valve only.
signals to the engine and pump controller (M). The
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