Daewoo Solar 420LC-V, Руководство пользователя

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Page 4 Swing Motor
If oil flow to the motor is directed to the opposite port (so that the supply side becomes the exhaust side
and vice versa), the rotation of the motor is reversed.
Trench mode allows the operator to "prioritize" hydraulic oil flow between swing function and boom and
arm function. Turning "ON" the trench mode boosts oil flow to swing circuit components, increasing swing
speed, as boom up/arm dump speed is reduced. If trench mode is turned "OFF" - diminishing the size of
the opening through the swing priority valve - boom/arm speed increases as slew rate falls off.
Connected through the EPOS-V controller, the switch of the trench mode changes the voltage of the
electronic signal sent to the solenoid valve.
When the trench mode is engaged, an engaged voltage signal to the solenoid valve shifts the "swing
priority" spool valve to increase oil flow through the swing motor. With trench mode "OFF," voltage is
disengaged while current flow is reduced, shifting the spool in the priority valve for increased oil flow to the
boom/arm side of the circuit.
SWING MOTOR ANTI-CAVITATION MAKE-UP VALVE
Unlike those designs for hydraulic swing motor application which incorporate a separate, external
counterbalance valve, the problem of motor rotational speed overtaking or surpassing oil flow rate at the
motor’s supply-side inlet is answered with pressure-control valving that is incorporated in the motor casing.
An anti-cavitation "make-up" valve is incorporated into each relief valve (Figure 2) to prevent oil starvation
on whichever side of the motor is serving as the supply side by allowing greater oil flow through one side of
the circuit. There is one valve for each side of the motor. When swing motor case drain pressure increases
past the set value of the make-up valves, oil flow is increased through that side of the motor circuit.
IMPORTANT
The trench mode setting only has a noticeable effect if both functions are used at the same time,
when the right and the left joysticks are each engaged simultaneously, to control swing and
boom/arm functions.