Building Conveying System Flashcards
Are generally used in buildings where several peak periods of traffic occur each day.
Elevator
Two Types of Elevators
- Electrical Elevators
- Oil-Hydraulic Elevators
A room housing the hoisting machinery, control equipment, and sheaves for raising and lowering an elevator car.
Machine Room
The structural steel frame of an elevator car to which are attached the platform, guide shoes, elevator care safety, hoisting cables and control equipment
Car Frame
A light, usually over the entrance to an elevator on each floor of a multistory building that signals the approach of the elevator
Lantern
A signaling apparatus in an elevator car or at a landing that displays a visual indication of floor landings
Annunciator
A push button for requesting an elevator
Call button
A safety device for preventing the operation of an elevator car unless the hoistway door is locked in the closed position.
Door Interlock
8 Parts of an Electric Elevator
- Shaft
- Car
- Cables
- Counterweights
- Guide Rails
- Machine Room
- Elevator Machine
- Controls
vertical passage way for car and counterweights
Shaft
a cage of light metal supported on a structural frame, the top member of which the cables, that carry the car are fastened.
Car
are the means for lifting and lowering the car, usually 3 - 8 cables placed in parallel fastened to top of car by cable socket passing over a motor driven cylindrical sheave to the counterweights.
Cables
these are rectangular blocks of cast iron stacked in one frame which is fastened to the opposite ends of the cables to which the car is fastened.
Counterweights
are vertical tracks that guide the car and the counterweights
Guide Rails
a room usually placed directly above the shaft in which the elevator machine is housed. It contains the motor-generator (MG) set which supplies energy to the elevator machine, the control board and the control equipment
Machine Room
turns the sheave that lifts and lowers the car
Elevator Machine
a combination of push buttons, contacts, relays, and devices, operated manually or
automatically to initiate door opening, starting acceleration, retardation, leveling
and stopping of the car.
Controls
4 Safety Devices
a. Main Brake
b. Safety Switch
c. Electric Final Limit Switches
d. Oil or Spring Buffers
Mounted directly on the shaft of the elevator machine.
Main Brake
is designed to stop an elevator car automatically before car speed becomes excessive. On overspeed, the speed governor will cut off power to the motor
and set the brake
Safety Switch
are located a few feet below and above safe travel limits of elevator car. If car over-travels, either down or up, these switches de-energizes the motor and sets the main brake
Electric Final Limit Switches
are placed at the bottom of the elevator pit, not to stop a falling car, but to bring it to a partially cushion stop if the car should overshoot the lower terminal.
Oil or Spring Buffers
supporting cables pass over the sheave in grooves and connect to the counterweights. The lifting power is exerted by the sheave through the traction of the cables in the grooves.
Single Wrap Traction Machine
cables first wrap over the traction sheave T, then around the secondary or idler sheave S, and once more going around T and S to the counterweights. This provides greater traction and is used in many
automatic high-speed installations.
One to One Double Wrap Traction Machine
This 2:1 roping, has a mechanical advantage of 2, which results in a high-speed, low-power and
therefore, low-cost traction machine.
Two to One Double Wrap Traction Machine
is used where the elevator machine is located at the basement
Underslung System
2 Types of Elevator Machines
- Gearless Traction Machine
- Geared Traction Machine
consists of a DC motor, the shaft of which is directly connected to the brake wheel and to the driving
sheave. The elevator cables are placed around this sheave. This type of machine is used for medium and high speed elevators for office and
residential condominiums of 10 stories or more; where high speeds
and smooth quality operation are
desired.
Gearless Traction Machine
this type of machine employs a
worm and gear between the driving
motor and the sheave. It is
considered to be less superior to the
gearless traction machine since it
has more moving parts and requires
more maintenance. Used for low
and medium speed passenger and
freight elevators
Geared Traction Machine
this is the simplest of passenger operated automatic control system.
It handles only one call at a time providing an uninterrupted trip for
each call.
Single Automatic Push Button Control
control is arranged to collect all waiting up calls on the trip up and all
waiting down calls on the trip down. The control system, stalls all calls
until they are answered and
automatically reverses the direction of travel at the highest and the lowest calls. When all calls have
been cleared, the car will remain at the floor of its last stop awaiting the
next call
Collective Control
this system is used to control not
only single elevators but an entire
group or bank of cars. During peak
periods, all cars are in operation;
automatically, the system shuts
down successively cars as the
number of passengers reduces and
return them to service as the
number of passengers again
increases to a high peak.
Electronic Group Supervisory Dispatching and Control
Systems of Elevator Controls
- Single Automatic Push Button Control
- Collective Control
- Electronic Group Supervisory Dispatching and Control
Parts of an Escalator System
- Truss
- Tracks
- Sprocket Assemblies, Chains and Drive Machine
- Controller
- Handrail and Balustrade Assembly
used where large numbers of people
are scattered throughout a given
area and on a large number of
floors. These people being
interested in moving about almost
constantly to various locations for
short periods of time.
Escalator
a welded steel frame which supports
the moving stairway equipment. It
comes in 3 sections: the middle
straight section maybe of any
desired length to provide rises of
different heights.
Truss
are steel angles attached to the
truss on which the step rollers are
guided thus controlling the motion of
the steps.
Tracks
provide the motive power for the
unit. An emergency brake located on
the top sprocket will stop a loaded
escalator safely in the event of a
break in the chain.
Sprocket Assemblies, Chains and Drive Machine
consists of contactors, relays and a
circuit breaker. Usually located near
the drive machine, an emergency
stop button wired to the controller
and placed in or near the escalator,
will stop the drive machine and
apply the brake. Key operated
control switches, at the top and
bottom newels, will start, stop, and
reverse the direction of travel of the
stairway.
Controller
4 Fire Protection Systems of Escalators
- Rolling Shutter
- Spray Nozzle Curtain
- Smoke Guard
- Sprinkler Vent
Escalator Types of Installations
- Horizontal or Level
- Bi-Level
- Overpass Installation
- Underpass Installation
This shuts off the well way at a given
floor, thus preventing draft and the
spread of fire upward through
escalator wells. The movement of
the shutter is actuated by
temperature and smoke relays.
Rolling Shutter
are closely spaced, high-velocity
water nozzles which will, in the case
of fire, form a compact water curtain
to prevent smoke and flame from
rising through the well ways.
Automatic thermal or smoke relays,
open all nozzles simultaneously.
Spray Nozzle Curtain
consists of fire proof baffles
surrounding the well way, extending
downward about 20” below ceiling
level. Smoke and flames rising
upwards, meet a curtain of water
from sprinkler heads surrounding
the baffles, which serves as a
smoke and flame deflector. Vertical
shields between adjacent sprinklers,
ensure that the spray from one will
not cool the nearby thermal fuses
and prevent the opening of adjacent
sprinklers.
Smoke Guard
Well way floor openings have a duct
on each floor equipped with a
number of smoke pick up relays. In
case of fire, these relays
automatically start the fans in the
fresh air intake, located on the roof,
driving air downward through the
well ways. Dangerous gases and
smoke are drawn in thru the ducts
and exhausted at the roof. The usual
spray nozzles on the ceiling around
the stair well aid in quenching the
fire.
Sprinkler Vent
Any of various forms of mass transit, as
moving sidewalks or automated driverless
vehicles, used for shuttling people around
airports or in congested urban areas
People Mover
A power-driven, continuously moving
surface, similar to a conveyor belt,
used for carrying pedestrians
horizontally or along low inclines
Moving Sidewalk
A platform mounted on a steel
guide rail and driven by an
electric motor used for raising
or lowering a person or moving
along a stairway. Also called a
stair lift
Inclined Lift
Also called plunger elevators. It is raised by means of a movable rod nor plunger rigidly fixed to the bottom of the car.
Oil Hydraulic Elevators
