topic 14: building conveying systems Flashcards
_____ is a platform or compartment housed in a shaft for raising and lowering people or things to different floors or levels.
elevator
______ is a small elevator for carrying things, especially food and dishes, between the floors of a building.
dumbwaiter
What are the 2 types of elevators?
- electric elevators
- oil hydraulic elevators
_____ are a type of elevator that operates using electric power for various components of its system.
electric elevators
Unlike traditional hydraulic elevators that use a system of pistons and fluid for movement, electric elevators rely on a system of _____, powered by an electric motor.
ropes and sheaves
What are the 9 parts of an electric elevator?
- shaft
- car
- cables
- counter weights
- guide rails
- machine room
- elevator machine
- controls
- safety devices
______ is the vertical passageway for car and counterweights.
shaft
______ is 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 or lowering the car, usually 3 to 8 cables placed in parallel fastened to top of car by cable sockets passing over a motor driven cylindrical sheave to the counterweights.
cables
Cables for electric elevators are usually ______ cables placed in parallel.
3-8
____ 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
_____ is a room usually placed directly above the shaft in which the elevator machine is housed.
machine room
The _____ contains the motor-generator (MG) set which supplies energy to the elevator machine, the control board and the control equipment.
machine rooms
The _____ turns the sheave that lifts and lowers the car.
elevator machine
The _____ is 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
What are the 4 safety devices?
- main brake
- safety switch
- electrical final limit switches
- oil or spring buffers
The ____ is mounted directly on the shaft of the elevator machine.
main brake
The _____ is designed to stop an elevator car automatically before car speed becomes excessive.
safety switch
On overspeed, the _____ will cut off power to the motor and set the brake.
speed governor
The ______ usually stops the car, but should speed still increase, the governor will actuate rail clamps mounted at the bottom of the car one on each side.
speed governor
_____ are located a few feet below and above safe travel limits of elevator car.
electric final limit switches
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
What are the 4 methods of arranging elevator machines, sheaves and ropes?
- single wrap traction machine
- one-to-one double wrap traction machine
- two-to-one double wrap traction machine (for freight elevators)
- underslung system
_____ is when supporting cables pass over the sheave in grooves and connect to the counterweights.
single wrap traction machine
The lifting power is exerted by the sheave through the traction of the cables in the grooves.
single wrap traction method
____ is when the 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.
one-to-one double wrap traction machine
____ 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
What are the 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.
gearless traction machine
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.
geared traction machine
____ is
considered to be superior to the gearless traction machine since it has more moving parts and requires more maintenance.
geared traction machine
_____ is used for low and medium speed passenger and freight elevators.
geared traction machine
What are the 3 systems of elevator controls?
- single automatic push button
- collective control
- electronic group supervisory dispatching and control
____ is the simplest of passenger operated automatic control system.
single automatic push button control
_____ 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.
collective control
The control system, stalls all calls until they are answered and automatically reverses the direction of travel at the highest and the lowest calls.
collective control
____ system is used to control not only single elevators but an entire group or bank of cars.
electronic group supervisory dispatching and control
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
The system of Otis Elevator Company is called “______”.
autotronic elevatoring
The system of Westinghouse Electric Co. is called the “_____”.
selectomatic elevator system
______ are also called plunger elevators.
oil hydraulic elevators
It is raised by means of a movable rod nor plunger rigidly fixed to the bottom of the car.
oil hydraulic elevators
The system is hydraulic and operates the same way as a hydraulic automobile jack. Oil from a reservoir is pumped under the plunger thereby raising it and the car.
oil hydraulic elevators
In oil hydraulic elevators the pump is stopped during ______, the car being lowered by gravity and controlled by action of bypassed valves which also controls the positioning of the car during the upward motion.
downward motion
The absence of cables, drums, MG set and penthouse equipment, makes this system inexpensive and often the choice for low speed, low rise applications where construction of the plunger pit does not present difficulties and where absence
oil hydraulic elevators
_______ is used where large numbers of people are scattered throughout a given area and on a large number of floors.
escalators and conveyors
These people being interested in moving about almost constantly to various locations for short periods of time. Thus traffic is constantly on the move both up and down.
escalators and coveyors
Examples are department stores and terminal buildings.
escalators and conveyors
What are the 5 parts of an escalator installation?
- truss
- tracks
- sprocket assemblies, chains, and drive machine
- controller
- handrail and balustrade assembly
A _____ is welded steel frame which supports the moving stairway equipment.
truss
The truss comes in 3 sections: _____, ______, ________
- upper landing section
- middle section
- lower landing section
The _____ maybe of any desired length to provide rises of different heights.
middle straight section
______ 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.
sprocket assemblies, chains, and drive machine
An _____ 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.
controller
Usually located near the drive machine, an ____ wired to the controller and placed in or near the escalator, will stop the drive machine and apply the brake.
emergency stop button,
_____, at the top and bottom newels, will start, stop, and reverse the direction of travel of the stairway.
key operated control switches
The _____ provides a convenient handhold for passengers while they are riding the escalator.
handrail
In an escalator, the ____ pulled along its track by a chain that is connected to the main drive gear by a series of pulleys.
handrail
The _____ consists of the handrail and the exterior supporting structure of the escalator.
Balustrade
It is the escalator exterior components extending above the steps and it supports the handrail.
Balustrade
What are the 4 fire protection systems of escalators?
- rolling shutter
- spray nozzle curtain
- smoke guard
- sprinkler vent
_____ shuts off the well way at a given floor, thus preventing draft and the spread of fire upward through escalator wells.
rolling shutters
_____ 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.
spray nozzle curtain
_____ consists of fire proof baffles surrounding the well way, extending downward about 20” below ceiling level.
smoke guard
Smoke guard fire proof baffles extends downward about ____ below ceiling level.
20”
Well way floor openings have a duct on each floor equipped with a number of smoke pick up relays.
sprinkler vent
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.
sprinkler vent
While escalators are used to transport people vertically, _____ are used to transport people horizontally at any inclination from 0 deg to 15 deg.
moving sidewalks or electric walks
moving sidewalks or electric walks are inclined from _____.
0-15 deg.
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
____ are assemblies that are used for the quick evacuation of materials from an elevated work location.
chutes
_____ use gravity to guide the flow of materials into a bin.
chutes
Often, _____ are installed both at the top of the chute system and at multiple locations along the chute riser.
sprinkler heads
