Posi-Plus Line Runner 700-40, Руководство оператора

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Oct-18-700 Operation Page 24 of 34
Section 6 - Operation
Booms
This unit is a non-overcenter type design that uses a hydraulic cylinder to raise and lower
the boom. The boom may be actuated from the upper controls' joystick.
The lower hydraulic controls may also be used to operate the boom when the toggle switch
at pedestal is maintained in the "Override” position.
Lower Boom
The lower boom can be articulated from 20 degrees below the horizontal (-20°) to 80
degrees above the horizontal (+80°).
Boom extension and retraction
The upper boom is hydraulically extended or retracted by the use of a hydraulic cylinder
controlled from either the upper or lower control stations.
Boom rotation
The standard 700-40 aerial device can be rotated
through 370 degrees after the boom has been
elevated to clear any obstacles. The standard boom
rotation movement stops approximately at 11
o'clock (on the roadside).
A planetary gearbox is used to drive the outer race
of the rotation bearing. The gearbox pinion meshes
with the rotation bearing gear teeth to rotate the unit.
A hydraulic motor drives the planetary in the
gearbox.
The rotation motor is equipped with a spring applied,
hydraulically released brake. This means the brake
is engaged until it is released by hydraulic pressure.
When the rotation control handle is shifted, pressure
begins to build up in the rotation motor. This pressure releases the brake and allows the
motor to rotate the aerial device. When the control handle is returned to neutral, the
rotation motor stops and the pressure in the brake decreases. As the pressure in the
motor decreases, the brake is applied and the rotation motion is stopped.