| Access Plate |
A removable cover to provide access to operating
parts. |
| Actuator |
A device for converting potential energy into
mechanical energy. |
| Air/Hydraulic |
A system, which uses compressed air to run
hydraulic pumps. |
| Angular Creep |
Extremely slow speed movement of a tilter that is
the result of normal leakage of fluid control
valves. |
| Angular Travel |
The angular difference between the two tilting
travel limits of the platform deck or forks, expressed
in degrees. |
| Approach Ramp |
A rigid structure to span a gap between the floor
and a platform. |
| Authorized Person |
Trained or qualified personnel approved or assigned to
perform a specific duty or duties (see Qualified person
or Trained person). |
| Automatic Landing Gate |
A landing gate that automatically opens or closes,
respectively, as a lift platform arrives at or departs
from subject landing. |
| Axle Load |
The dynamic load on the edge of a lift platform
when a wheeled vehicle is rolled on. |
| B20.1 |
ASME Standard for Conveyors (VRC's) |
| Bearing |
Normally a low-friction needle roller or ball lined
support for a rotating shaft. |
| Bellows Guards |
Fabric-like accordion skirting to enclose under the
base and legs. |
| Bevel Toeguards |
Platform sides slanted inwardly at an angle of
approximately 30 degrees from vertical in order to
eliminate shear edges (commonly used in pit-mounted
installations). |
| Bleed-Off |
Diversion of pressurized hydraulic fluid back to
reservoir. |
| Bushing |
The lining of an inside surface to reduce
friction. |
| By-Pass |
An alternative passage for fluid flow. |
| CO |
Customer Order |
| CS-202-56 |
Commercial Standard (-56=1956) |
| CSM |
Customer Supplied Material |
| CTD |
Cumulative Trauma Disorders |
| Cam Follower |
A hi-capacity roller bearing used to carry or guide
load. |
| Center of Gravity |
The point at which a mass can be supported, in any
position, and remain in equilibrium without
tipping. |
| Check Valve |
A valve that allows fluid flow in one direction
only. |
| Circuit |
Interconnected components through which energy or
signals flow. |
| Clevis |
A structural mounting device to support a pin (i.e.
used in attaching platform to legs). |
| Compressibility |
The change in volume of a fluid or solid when
subjected to pressure. |
| Continuous Duty |
An electric motor rated to operate
continuously. |
| Control Transformer |
An electrical device that changes the voltage of a
circuit. |
| Control Voltage |
The voltage in the lift controls circuit. |
| Critical Components |
Those components whose absence or failure would
cause the equipment, of which they are a part, to
become inadequate or unsafe for its specific
purposes. |
| Cross Tube |
A welded structural cross member between the legs
of a scissors lift used to equalize loading between the
legs. |
| Cycle |
For lift tables, one complete up and one complete
down operation. |
| Cylinder |
A fluid vessel with piston and shaft that moves as
fluid pressure increases or decreases. |
| Cylinder, Double
Acting |
A cylinder in which fluid force can be applied to
either side of the piston. |
| Cylinder, Ram |
A cylinder in which the piston and shaft have the
same diameter. |
| Cylinder, Single |
Acting A cylinder in which the fluid force can be
applied to only one side of the piston. |
| DC |
Direct Current (Electricity) |
| DHHS (or DHS) |
Department of Health and Human Services |
| Displacement |
The volume of fluid a pump moves in one cycle. The
volume of fluid in a cylinder at full stroke. |
| Dock Lift |
A lift whose travel is generally 5 feet or less and
which is used to load/unload material from trucks and
transfer it to dock or ground elevation. |
| Down Valve |
A hydraulic control valve, which allow oil to
return to the reservoir. |
| DU Bushing |
A pre-finished, high performance bushing used at
the pivot points. |
| Ductile |
Describes material capable of sustaining not less
than 5% elongation before it fractures. |
| Dynamic Load |
A moving load. |
| Edge Load |
The load on a platform edge as a result of
off-center loading. |
| Electric Toeguard (toe
sensor) |
A contact device that stops the down travel of a
lift table when an obstruction is encountered. |
| Electric/Hydraulic |
A system which converts electric power to hydraulic
power. |
| End/Side Axle Load
Capacity |
The maximum amount of single axle load (in the case
of rolling loads), which may be applied to the loading
edge of the platform (end or side) when the lift is in
its raised position. |
| End/Side Edge Load
Capacity |
The maximum amount of static load that can be
applied to the edge of platform (end or side) when the
lift is in any raised position. |
| FPM |
Feet Per Minute |
| Flow Control Valve |
A valve which controls the rate of flow of
hydraulic fluid. |
| Flow Rate |
The volume of fluid passing through a pipe or hose
at a given time. |
| Four-Way Valve |
A valve which can direct fluid flow in 4
directions. |
| Hinged Bridge/Throw-over
Plate |
A hinged transition plate attached to the edge of
the platform to provide a bridge to a loading dock or
truck bed. |
| Hydraulic Piping
System |
The entire system of fluid conduits such as hose,
pipe, tubing, etc. used to transfer hydraulic fluid
between various operating components of the hydraulic
systems such as pumps, valves, actuators, etc. |
| Interlock |
A device to prevent lift movement when a landing
gate is not fully closed and to prevent the landing
gate from being opened unless the lift platform is
present at that landing. |
| Intermittent Duty |
An electric motor rating for part-time
operation. |
| Jog |
To raise or lower the lift platform in short
increments. |
| LSD |
Double Wide or Tandem Wide Scissors Lift |
| LSH |
Double Pantograph Scissors Lift |
| LST |
Double Long or Tandem Long Scissors Lift |
| LMPS |
Lift Manufacturers Product Section (MHI) |
| Landing |
A permanent working surface at a fixed elevation
used for loading/unloading a lift or tilter device |
| Landing Gate |
A gate to control personnel traffic at a
landing. |
| Lift Table |
A scissors lift device used to raise, lower, stack,
convey and/or transfer material between two or more
elevations and not limited to landings. |
| Lifting Capacity |
The rated load of a scissors lift applied as a
uniformly distributed load |
| Limit Switch |
An electrical device, which by predetermined
adjustment, limits the rotational or linear movement of
a mechanism. |
| MH29.1 |
ANSI Standard for Industrial Scissors Lifts |
| MH29.2 |
ANSI Standard for Industrial Tilters |
| MH30.1 |
ANSI Standard for Dock Levelers |
| Maintained (Contact)
Control |
Mode of control where movement starts when the
control device is actuated and continues when the
control device is released. Movement stops when either
an appropriate limit switch is actuated or the
Emergency Stop button is pressed. NOTE: Whenever a
machine's control is maintained, an Emergency Stop
button must be supplied and located where it can be
reached by the operator. This applies when even a
portion of a machine's operating sequence includes
maintained control. |
| Maintenance Chock |
A device used to mechanically support a lift or
tilter in the up position for maintenance. |
| Manual Control |
A control actuated by the operator, regardless of
the means of actuation. |
| Manual Override |
A control that allows manual operation of an
otherwise automatically controlled device |
| Momentary (Contact)
Control |
Mode of control where movement starts when the
control device is actuated and stops when the control
device is released (a.k.a. "Deadman" control). |
| Motor |
A device which converts electrical energy into
rotational mechanical force. |
| N |
Narrow or Narrowed Scissors Lift |
| NEC |
National Electrical Code |
| NFPA |
National Fire Prevention Association |
| NEMA |
Classification National Electrical Manufacturers
Association Standard. |
| NIOSH |
National Institute for Occupational Safety and
Health |
| ODP |
Open Drip Proof Motor |
| OSHA |
Occupational Safety and Health Administration |
| Operator |
Trained person controlling the movement of the
lift. |
| PSF |
Pounds Per Square Foot |
| PSI |
Pounds Per Square Inch |
| Pantograph Leg Section |
The articulated support mechanism characterized by
a single pivot axis and commonly referred to as the
scissors leg assembly. |
| Piston |
A cylindrically shaped part which fits within a
cylinder and is actuated by fluid pressure. |
| Platform Ends |
The edges of the platform that are perpendicular to
the scissors leg. The end dimension is considered the
platform width. |
| Platform/Fork Length |
The platform or fork dimension as measured
perpendicular to the hinged edge (tilt axis). This is
considered the side of the platform or fork. |
| Platform/Fork Width |
The platform or fork dimension as measured parallel
to the hinged edge (tilt axis). This is considered the
end of the platform or fork. |
| Platform Sides |
The edges of the platform that are parallel to the
scissors legs. The side dimension is considered the
platform length. |
| Pneumatic |
Relating to air or another gas. |
| Pneumatic Piping
System |
The entire system of pneumatic conduits such as
hose, pipe, tubing, etc. utilized to transfer air or
other gas between various operating components of the
pneumatic system such as pumps, valves, actuators,
etc. |
| Point Load |
A concentrated load. |
| Poppet |
A check or one-way valve. |
| Pressure |
Force per unit of area, usually expressed as pounds
per square inch (psi). |
| Pressure Line |
The line carrying pressurized fluid from the pump
to the cylinders. |
| Pump |
A device which causes a liquid to flow under
pressure. It converts mechanical force into hydraulic
pressure. |
| Qualified Person |
A person, who by possession of a recognized degree,
certificate, professional standing, or skill, and who
by knowledge, training and experience has demonstrated
the ability to deal with problems relating to the
subject matter, the work or the project. (See
Authorized Person and Trained Person). |
| Quick Disconnect |
A means of rapidly connecting and disconnecting
electric or hydraulic lines. |
| RPM |
Revolutions Per Minute |
| Rated Capacity |
The maximum uniformly distributed load, which can
be applied according to the manufacturer's
specification. |
| Rated Load |
The maximum capacity as specified by the equipment
nameplate. |
| Relief Valve |
A valve that operates at the preset pressure to
allow the escape of fluids. |
| Reservoir |
A vessel for storage of hydraulic fluid, which is
not under pressure. |
| Return Line |
A line used to carry hydraulic fluid from the
cylinders back to the reservoir. |
| Rollover Capacity |
The maximum amount of single-axle load, which may
be rolled over, the platform surface when the lift is
in its fully closed position. |
| SAE |
Society of Automotive Engineers |
| SME |
Society of Manufacturing Engineers |
| Scissors Lift |
A raising/lowering device that is supported or
stabilized by one or more pantograph leg sections. |
| Semi-Live Portability |
A lift table with non-castered wheels at one end
and a wheeled skid spotter at the opposite end. |
| Shall |
The word "shall" is to be understood as
mandatory. |
| Should |
The word "should" is to be understood as
advisory. |
| Signal |
A command to or feedback from an actuator or
sensor. |
| Single Acting Cylinder |
See Cylinder, Single Acting. |
| Static Load |
A stationary load. |
| Strength Factor |
The ratio of ultimate strength of a material to its
design stress and maximum rated capacity. |
| Stroke |
The length of travel of a piston or piston
rod. |
| Strong Back |
A cross member on a scissors lift used to equalize
loading between the scissors legs. |
| Suction Line |
The hydraulic line from the reservoir to the pump
inlet (suction side). |
| TEFC |
Totally Enclosed Fan Cooled Motor |
| TENV |
Totally Enclosed Non-Ventilated Motor |
| Throw-Over Plate |
See Hinged Bridge/Throw-Over Plate |
| Thrust Angle (Strong
Back) |
A cross member on a scissors lift where the
cylinder pushes on to create the travel. |
| Torque |
Twisting force (expressed in inch pounds or foot
pounds). |
| Trained Personnel |
Personnel who have been trained by a qualified
person and have demonstrated the ability to perform a
particular function on or around a scissors lift or
tilter. (See Authorized Person and Qualified
Person) |
| Trunnion |
See Strong Back or Thrust Angle. |
| Two-Way Valve |
A valve which can direct fluid flow in two
directions. |
| UL |
Underwriters Laboratories (Inc.) |
| VRC |
Vertical Reciprocating Conveyor |
| Valve |
A device which directs and controls the pressure
and flow rate of a fluid. |
| Velocity Fuse |
A hydraulic valve which senses rapid increase in
the speed of the fluid (i.e. a break in a hydraulic
line) and locks the fluid in the cylinder to prevent
the lift or tilter from falling. |
| Vertical Creep |
Extremely slow speed movement of a scissors lift
that is the result of normal, internal leakage of the
fluid control valves. |
| Vertical Travel |
The difference between fully raised height of the
platform deck and fully lowered height of the platform
deck. |
| Volume |
The three-dimension size of a space of chamber
(cubic inches). The output of a pump as expressed in
gallons per minute (gpm). |
| W |
Wide or Widened Scissors Lift |
| Watt |
A measure of electrical energy (volts x
amperes). |
| Wheel Chock |
A wedge-shaped device to prevent wheels from
rolling. |