Swing - JLG TOUCAN 10E Service And Maintenance Manual

To lift the jib, the pump is run and an appropriate signal is
sent to the proportional relief valve. Then after a short
delay, the jib up solenoid energizes and opens the jib up
valve. The pump speed is set proportional to joystick posi-
tion. Fluid flows into the jib cylinder and extend the rod.
To bring down the jib, an appropriate electric signal is
sent for the proportional relief valve to close and the pump
is run for a short period of time to pressurize the circuit.
Once the circuit is pressurized, the jib down valve opens
and the load is held by the proportional pressure relief
valve. Then, the pressure relief valve opens proportional
to joystick position, and allows fluid back to the tank,
allowing the jib to go down by gravity.
Figure 3-5. Jib Lift System - Basic Schematic
31210090
SECTION 3 - THEORY OF OPERATION

Swing

Swing is actuated by a hydraulic motor.
To swing to the right, the solenoid of the swing valve ener-
gizes, an appropriate electric signal is sent to the propor-
tional relief valve and the pump speed is set proportional
to joystick position. Pressure is applied to one port of the
motor and drained from the other, allowing the motor to
turn.
To swing to the left, the solenoids of both the swing and
the flow directional valve energize, an appropriate electric
signal is sent to the proportional relief valve and the pump
speed is set proportional to joystick position. Pressure is
applied to one port of the motor and drained from the
other, allowing the motor to turn.
Figure 3-6. Swing System - Basic Schematic
– JLG Lift – 3-5