Altec DRM 12, Руководство пользователя

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11
Appendix — Glossary
pullout upper controls — an upper control panel on a digger derrick
which is mounted on a housing that can be extended from inside an
outer housing when additional length is needed, such as to attach the
control panel to a personnel jib with the outer housing attached to the
upper boom tip, or to attach the upper control panel to the upper boom
tip with the outer housing attached to the transferable boom flares.
pulse width modulation (PWM) — a means of transmitting a digital
signal in continuous cycles of pulses where the total length of time for
a cycle of one “on” pulse and the following “off” period is constant, and
the length of time (width) of the “on” pulse within each cycle is varied
(modulated) in proportion to the level of an input parameter such as
control lever position.
pump — a device that converts mechanical force and motion into
hydraulic flow and pressure.
purge system — a system of check valves that allows hydraulic
fluid flow in a reverse manner through the hydraulic system, usually
from the lower control valve to the upper controls. This actions frees
or purges the control system of any trapped air and restores a solid
column of fluid for precise control. The purge system may also be used
to warm up the control system in cold weather conditions if the fluid
in the reservoir is warm.
purge/upper/lower controls selector valve — a valve which is used
to direct hydraulic fluid to the purge system, the upper control valve,
or the lower control valve.
PWM — pulse width modulation.
quick disconnect couplings — hydraulic fittings designed for fast
and easy attachment and separation.
radial ball bearing — an antifriction bearing with rolling ball contact
in which the direction of action of the load transmitted is perpendicular
to the axial centerline of the bearing.
radial outrigger — an outrigger in which the moveable outrigger leg
pivots in an arc around a pin connection between the leg and a sup-
porting structure as the leg is lowered and raised.
radio communication — communication by means of radio waves.
ram — 1: a single-acting cylinder with a single diameter plunger rather
than a piston and rod. 2: the plunger in a ram-type cylinder.
ram cylinder — the hydraulic cylinder that is used to retract and extend
the kelly bar on a pressure digger.
ramp — an adjustable delay to govern the response of the hydraulic
valve when a unit is operated from the electronic controls.
range diagram — a diagram which shows the load radius and sheave
height of a digger derrick at all the configurations of boom extension
and boom angle covered by the corresponding load capacity chart
.
rated capacity — (as defined by ANSI for digger derricks) the maximum
load, specified by the manufacturer, that can be lifted by the digger
derrick at regular intervals of load radius or boom angle, through the
specified ranges of boom elevation and extension, with specified op -
tions installed, and exclusive of stability requirements.
rated line voltage — the nominal voltage, phase to phase, at which
electrical systems are rated.
rated load capacity — (as defined by ANSI for aerial devices) the
maximum loads, specified by the manufacturer, which can be lifted
by the aerial device through the specified range of boom elevation
and extension with specified options installed and in consideration of
stability requirements.
reach diagram — a drawing that shows the horizontal and vertical
limits of travel of the platform, upper boom tip, and/or jib tip throughout
all possible configurations of lower boom angle, boom extension, upper
boom angle, articulating arm travel, and/or elevator lift travel.
rear jack stand — adjustable rear support used when the chipper is
in operation and not coupled to the tow vehicle.
rear mount — a pedestal mounting position located over or near the
rear axle(s) on the longitudinal centerline of the chassis.
receiver — a device that converts radio waves into electrical signals
for communication and/or control purposes.
reel brake
— a component of the reel driver which prevents the over-
running of cable reels carried by a strand carrier and reel lifter. The
brake is used to maintain tension in the cable or suspension strand
when used with the reel driver.
reel driver — a component of a strand carrier and reel lifter used for
paying in or paying out cable or suspension strand.
reel lifter — a device used to support and move cable reels from the
ground to the vehicle.
reel lifter arms — the structure on a reel lifter used to lift and store
reels of cable or suspension strand on the chassis.
reengage — to repeat the activation of a function after it has been
momentarily halted.
relay — an automatic switch with contacts that can be closed or opened
by electrical current in a coil.
relief valve — a pressure operated valve that bypasses pump delivery
to the reservoir to limit system pressure to a predetermined maximum
value.
remote arm — a remotely operated jib used to handle equipment or
electrical lines.
remote assist — a vehicle-mounted device with a boom assembly
which is extendible, articulating, or both, which is designed and used to
accommodate attachments for performing operations such as supporting
or cutting electrical conductors, lifting or holding objects, or cutting tree
branches. It is operated by remote control from the ground or from the
platform of an adjacent personnel lifting device. It may be mounted on
the vehicle by itself or in addition to a personnel lifting device.
remote control system — a system used for operating some or all
of the functions of a unit from a portable control station. The control
station may be a transmitter which sends signals by radio waves to a
receiver on the unit, or a control module which sends signals through
a fiber optic or electrical cable to the unit.
remote operated auxiliary control system (ROACS) — a radio
controlled system for starting and stopping certain functions of the
mobile unit.
remote start/stop system — the components used to actuate a
function of the unit from a location other than for normal operation.
The most common functions controlled are engine start/stop and the
secondary stowage DC pump.
reservoir — a container for storage of liquid in a fluid power system.
resistance
— the opposition to the flow of electricity or hydraulic
fluid.
restriction — a reduced cross-sectional area in a line or passage that
produces a pressure drop.
retaining ring — a hardened, washer-like ring that may be spread
apart or compressed and installed into a groove or recess to serve
as a retaining device.
return line — a hydraulic line used to carry discharge flow from a
hydraulic system or actuator back to the reservoir at low pressure.
return line filter — a filter located in a hydraulic system return line or
at the inlet of a hydraulic reservoir which cleans fluid flowing from the
hydraulic system to the reservoir.
reversing valve — a four-way directional valve used to change the di-
rection of movement of a double-acting cylinder or reversible motor.
ribbon hose — a group of hoses that are attached side by side to
produce a flat bundle. Commonly used to carry hydraulic fluid, air and/
or electrical cable(s) to the boom tip or upper controls.
riding seat — an operator’s control station attached to the side of the
turntable, with a seat on which the operator rides with the rotation of
the unit.
riser — 1: the structure on a double elevator that connects the lower
elevator arm to the upper elevator arm. 2: the structure within an ar-
ticulating arm to which the lower boom is connected.
ROACS — see remote operated auxiliary control system.
rod
— the cylindrically shaped part of a cylinder which extends and
retracts from the barrel to actuate or move a component.
rod end — the end of a cylinder that the extending component or
rod is on.
roller — a cylindrical device which spins freely about a pin or shaft,
used to guide the motion of another component.
rollpin — a pin that has been formed by rolling up a thin, flat strip of
metal to form a cylinder. Commonly used by being driven into a hole
to serve as a retaining device.
rope — a stout, flexible cord, which consists of many strands of wire
or fibers that are twisted or braided together.
rotary actuator — a device for converting hydraulic energy into rotary
motion and torque in which the rotary motion is restricted to within
certain angular limits.