An lift (USA and Canada) or elevators (UK, Australia, Ireland, New Zealand and South Africa, Nigeria) is a type of vertical transport that moves people or goods between floors (level, deck) of buildings, ships, or other structures. Elevators are generally powered by electric motors that drive traction cables and balancer systems such as hoists, or pumping hydraulic fluid to raise piston cylinders such as jack.
In agriculture and manufacturing, lifts are a type of conveyor device used to lift materials in a continuous stream into a barrel or a silo. Several types exist, such as chain and bucket lifts, wheat grain screw conveyors using the principle of Archimedes screw, or chain and oars or forks of straw elevators. Languages ​​other than English may have a loan word based on elevator or lift. Due to wheelchair access legislation, elevators are often a legal requirement in new storied buildings, especially where wheelchair heats are impractical.
Video Elevator
History
Pre-industrial era
The earliest known reference to elevators is in works by Roman architect Vitruvius, who reported that Archimedes (about 287 BC - about 212 BC) built his first elevator probably in 236 BC. Some sources from the historical period then mention the elevator as a taxi on a hemp rope that is moved by hand or by animal.
In the year 1000, The Book of Secrets by al-Muradi in Spanish Spain describes the use of lifting tools such as elevators, to raise a great concoction to destroy a fortress. In the 17th century, prototype elevators were placed in British and French court buildings. Louis XV of France had the so-called 'flying chair' built for one of his mistresses at the Chateau de Versailles in 1743.
Ancient and medieval elevators use drive systems based on hoists or glasses. The discovery of a system based on a screw drive may be the most important step in elevator technology since ancient times, leading to the creation of modern passenger elevators. The first screw drive lift was built by Ivan Kulibin and installed in the Winter Palace in 1793. A few years later, another Kulibin elevator was installed at Arkhangelskoye near Moscow.
Industrial era
The development of the elevator is led by the need for movement of raw materials including coal and wood from the hillside. The technologies developed by these industries and the introduction of steel beam construction work together to provide passenger lifts and goods in use today.
Started in a coal mine, in the mid-19th century the elevators were operated with steam power and used to move large quantities of goods in mines and factories. This steam-driven device was immediately applied to a variety of purposes - in 1823, two architects working in London, Burton and Hormer, built and operated a new tourist attraction, which they called "upstairs". This keeps customers paying to high altitudes in central London, enabling them to see magnificent city center views.
Early on, the steam-driven steam lift was perfected in the next decade; - in 1835, an innovative lift called "Teagle" was developed by the Frost and Stutt companies in England. The elevator is driven by a belt and uses a balancer for extra power.
Hydraulic cranes were invented by Sir William Armstrong in 1846, mainly for use at the Tyneside dock to load cargo. This quickly replaced the steam-driven elevators before: exploiting Pascal's laws, they gave them far greater strength. The water pump supplies variable water pressure levels to the plunger enclosed in a vertical cylinder, allowing the platform level (carrying heavy loads) to be raised and lowered. Counterweight and balance are also used to improve equipment lifting.
Henry Waterman of New York is credited with creating a "standing rope" for elevators in 1850.
In 1845, the Neapolitan Gaetano Genovese architect was installed at the Royal Palace of Caserta, the "Flying Chair", an elevator ahead of time, covered with chestnut wood outside and with maple wood in it. These include light, two stools and hand-operated signals, and can be switched from the outside, with no effort from the occupants. Traction is controlled by motor mechanics using a toothed wheel system. The security system is designed to apply if the cord is broken. It consists of a beam driven out by a steel spring.
In 1852, Elisha Otis introduced a safety elevator, which prevented the fall of the cable if the cable broke. The design of the Otis safety lift is somewhat similar to the one that is still in use today. The governor's device hooks the hardened roller (s), lifts the elevator to its driver if the elevator decreases with excessive speed. He demonstrated it at a New York exhibition at Crystal Palace in a dramatic presentation that challenged death in 1854, and the first such passenger lift was installed at 488 Broadway in New York City on March 23, 1857.
The first elevator shaft preceded the first elevator for four years. The construction for the Cooper Union Cooper Union Foundation building in New York began in 1853. The elevator shaft was included in the design, as Cooper believed that a safe passenger lift would soon be found. The rod is cylindrical because he thinks it is the most efficient design. Later, Otis designed a special elevator for the building.
The Equitable Life Building completed in 1870 in New York City is considered to be the first office building to have a passenger elevator. But Peter Ellis, an English architect, installed the first elevator that could be described as a paternoster elevator at Oriel Chambers in Liverpool in 1868.
The first electric elevator was built by Werner von Siemens in 1880 in Germany. Inventor Anton Freissler developed ideas from Siemens and built a successful company in Austria-Hungary. The safety and speed of the electric lifts are significantly enhanced by Frank Sprague which adds floor control, auto lift, car acceleration control, and safeties. The elevator runs faster and with a greater load of hydraulic or steam lifts, and 584 electric lifts are installed before Sprague sells its company to Otis Elevator Company in 1895. Sprague also develops ideas and technologies for multiple elevators in one axis.
In 1882, when hydraulic power was an established technology, the company later named London Hydraulic Power Company was formed by Edward B. Ellington and others. It builds a high-pressure power grid on both sides of the Thames River which, in turn, is extended to 184 miles and is supported by around 8,000 engines, mainly elevators and cranes.
Schuyler Wheeler patented his electric elevator design in 1883.
In 1874, J.W. Meaker patented a method that allows the elevator doors to open and close safely. In 1887, American Inventor Alexander Miles of Duluth, Minnesota patented an elevator with an automatic door that would cover the elevator shaft.
The first lift in India was installed at Raj Bhavan in Calcutta (now Kolkata) by Otis in 1892.
By 1900, automatic elevators were fully available, but passengers were reluctant to use them. A 1945, an elevator operator strike in New York City, and the adoption of emergency stop buttons, emergency phones, and automated voice annotations assisted by soothing sounds.
In 2000, the first vacuum lift was offered commercially in Argentina.
Maps Elevator
Design
Some people think that the elevator starts as a simple string or chain (see traction elevator below). The elevator is basically a platform that is pulled or pushed by a mechanical device. The modern elevator consists of taxis (also called "cages", "carriages" or "cars") installed on platforms in enclosed spaces called axis or sometimes "hoistways". In the past, the drive lift mechanism was powered by steam and hydraulic pistons or by hand. In the "traction" elevator, the car is pulled by twisting the steel ropes over a highly grooved pulley, commonly called industrial sheave. The weight of the car is offset by the counterweight. Sometimes two elevators are built so that their car always moves simultaneously in the opposite direction, and is a balancer of each.
The friction between the rope and the pulley completes the traction that gives the name of this type of elevator.
Hydraulic elevators use hydraulic principles (in the sense of hydraulic power) to push the piston above the ground or in the ground to raise and lower the car (see hydraulic elevators below). Hydraulics strap using a combination of rope and hydraulic power to raise and lower the car. Recent innovations include permanent magnet motors, engines without engines mounted on the tracks, and microprocessor controls.
The technology used in new installations depends on various factors. Hydraulic lifts are cheaper, but installing a cylinder larger than a certain length becomes impractical for very high lift hoistways. For buildings over seven floors, traction lift should be used instead. Hydraulic lifts are usually slower than traction lifts.
Elevators are candidates for bulk customization. There is an economy made from mass production of components, but each building has its own requirements such as number of different floors, well dimensions, and usage patterns.
elevator doors
The elevator doors protect the rider from falling to the shaft. The most common configuration is to have two panes that meet in the middle, and slide down. In telescopic configurations to flow (potentially allowing wider entrances in limited space), the doors roll on separate rails so that when open, they lie behind each other, and when closed, they form a layer of cascade on one side. This can be configured so that two sets of cascade doors like that operate like the middle opening door described above, enabling a very wide elevator cabin. In cheaper installations, the elevator can also use one large "slab" door: one wide panel door from the open door to the left or right laterally. Some buildings have elevators with single doors on the shaft, and double doors in the cabin.
Elevators with no engine room (MRL)
The elevator-less elevator engine is designed so that most of the components fit in a shaft that contains a car elevator; and a small house with an elevator controller. In addition to the engine located on the hoistway, the equipment is similar to normal traction or hydraulic lifts without holes. The world's first non-engine space elevator, Kone MonoSpace was introduced in 1996, by Kone. The benefits are:
- creates more usable space
- uses less energy (70-80% less than standard hydraulic lift)
- does not use oil (assuming it is a traction lift)
- all the above ground components are similar to hydraulically lined type lifts (this removes the environmental concern created by hydraulic cylinders in hydraulic direct-type elevators that are stored underground)
- slightly cheaper than other elevators; significantly so for the hydraulic MRL lift
- can operate at a faster speed than hydraulics but not a normal traction unit.
Detriments
- Tools can be more difficult to repair and maintain.
- The code is not universal for the hydraulic engine room minus the elevators.
Fact
- The noise level is 50-55 dBA (decibel weighing A), which can be lower than some but not all types of elevators.
- Usually used for low to medium rise buildings.
- The motor mechanism is placed in the hoistway itself
- The US is slow to accept commercial MRL Elevators because of code
- The national and local building codes do not discuss elevators without an engine room. Residential MRL Elevator is still not authorized by ASME A17 code in US. The MRL elevator has been recognized in 2005 supplement for the 2004 A17.1 Elevator Code.
- Today, some engine room minus hydraulic elevators by Otis and ThyssenKrupp exist; they do not involve the use of underground pistons or engine rooms, alleviating environmental problems; however, the code has not received it in all parts of the United States.
Double-tier elevators
The double-decker elevator is a traction lift with a car that has an upper and lower deck. Both decks can serve the floor at the same time, and both decks are usually driven by the same motor. This system increases efficiency in tall buildings and saves space so additional axles and cars need not be added.
In 2016, ThyssenKrupp created a system called TWIN, in which two elevator cars run independently in a pivot.
Elevator traffic calculation
Calculate back and forth
Most lift designs are developed from Peak Peak Peak Peak time calculations as described in the following publications: - CIBSE D Guide: Transportation System in Building Traffic Elevator Handbook, Theory and Practice. Gina Barney. Vertical Transport Handbook. George Strakosch
Traditionally, these calculations have formed the basis for the formation of the Handling Capacity of the elevator system.
Modern installations with more complex elevator settings have led to the development of more specific formulas such as General Analysis calculations.
Furthermore, it has been extended to Double Deck elevators.
Otis Elevator Company operates more than 1.9 million lifts worldwide, giving rise to claims that the world's population is transported by its products every five days.
Simulation
The elevator traffic simulation software can be used to model complex traffic patterns and elevator settings that can not be analyzed by RTT calculations.
Traffic lift pattern
There are four main types of elevator traffic patterns that can be observed in most modern office installations. They ride peak traffic, peak traffic drops, lunch time (two way) traffic and interfloor traffic.
The type of hoist mechanism
Elevators can rely on ropes or free cords. There are at least four ways to move an elevator:
Traction elevators
- Geared and gearless traction elevators
The traction engine is driven by an AC or DC electric motor. The engine is driven using a worm gear to control the mechanical movement of an elevator car by "rolling" a steel strap rope over a sheave drive attached to a gearbox driven by a high-speed motor. These machines are generally the best choice for the use of basement or traction overhead for speeds up to 3 m/s (500 ft/min).
Historically, AC motors are used for single or double speed speed machines on the basis of lower cost and application usage where the car's speed and passenger comfort is less of a problem, but for higher speeds, larger elevator capacity, the need for speed control the infinite variable over the traction engine becomes a problem. Therefore, a DC machine powered by an AC/DC generator is the preferred solution. The MG set is also typically supported by elevator relay controllers, which have the added advantage of isolating elevators from the rest of the building's electrical system, eliminating power spikes while in building supplies caused by motor start and stop (causing dim lighting every time the lift is used for example) interference with other electrical equipment caused by relay contactor loops in the control system.
The wide availability of variable frequency air conditioners has enabled AC motors to be universally used, bringing the advantages of old motor generators, DC based systems, without penalty in terms of efficiency and complexity. Older MG-based installations are being gradually replaced in older buildings due to poor energy efficiency.
Gearless traction machine is a low-power, low-torque electric motor driven by AC or DC. In this case, the sheave drive is connected directly to the end of the motor. Gearless traction elevators can reach speeds up to 20 m/s (4,000 ft/mnt), Rem A is mounted between the motor and the gearbox or between the motor and the sheave drive or at the end of the sheave drive to hold the elevator stationer on the floor. This brake is usually an external type of drum and is driven by a spring force and left open electrically; power failure will cause the brakes to engage and prevent the elevator from falling down (see inherent safety and safety techniques). But it could also be some kind of disk like 1 or more calipers over the disk at one end of the motor shaft or sheave drive used in high speed, high lift and large capacity with engine space (the exception is the non-high-speed, non-high-speed EcoDisc MonoSpace Kone high and large capacity and less engine space but using the same design as a thinner version of a tractionless engine without conventional gear) for braking, compactness and redundancy (assuming there are at least 2 calipers on the disk), or 1 or more disc brakes with a single caliper at either end of the motor shaft or sheave drive used in the engine room minus the elevators for compactness, braking power, and redundancy (assuming there are 2 or more brakes).
In each case, the cable is mounted on the hitch plate above the cab or may "underslung" beneath the cab, and then looped over the sheave drive to a counterweight attached to the end of the cable that reduces the amount of power required to move the cab. Counterweight is located in a hoist-way and up a separate rail system; when the car goes up, the balancer goes down, and vice versa. This action is supported by a traction engine directed by the controller, usually a relay logic or computerized device that directs the start, acceleration, retardation, and termination of the elevator. Balancing weight is usually the same as the weight of the elevator cabin plus 40-50% of the lift capacity. The groove on the sheave drive is specially designed to prevent the cable from slipping off. "Traction" is given to the rope with a groove handle on the sheave, as the name suggests. As the rope age and traction indent, some traction is lost and the rope must be replaced and sheave repaired or replaced. Sheave and rope wear can be reduced significantly by ensuring that all ropes have the same voltage, thus sharing the load evenly. Equation of strain tension can be achieved by using a rope tension gauge, and is a simple way to extend the life of the rope and rope.
Elevators with more than 30 m (98 ft) travel have a system called compensation. This is a set of separate cables or chains that stick to the bottom of the counterweight and the bottom of the elevator cabin. This makes it easier to control the elevators, as it offsets the weight difference between cables and cabin hoist. If the elevator cabin is at the top of the hoist-way, there is a short hoist cable above the car and the length of the compensation cable under the car and vice versa for the counterweight. If the compensation system uses a cable, there will be an extra sheave in the pit below the lift, to guide the cable. If the compensation system uses a chain, the chain is guided by a bar mounted between the line of the ballast rail.
Hydraulic elevators
- Conventional hydraulic elevators . They use underground hydraulic cylinders, quite common for low-rise buildings with two to five floors (sometimes but rarely up to six to eight floors), and have speeds of up to 1 m/s (200 ft/min). For higher applications, telescopic hydraulic cylinders can be used.
- Hydraulic lifts without wheels developed in the 1970s, and used a pair of cylinders on the ground, which made it practical for buildings that were environmentally sensitive or cost two, three, or four floors.
- Strong hydraulic elevator uses above ground cylinders and rope systems, allowing elevators to travel farther from the piston to move.
The lower mechanical complexity of hydraulic lifts compared to traction lifts makes them ideal for low traffic installs. They are less energy efficient because the pump works against gravity to push the car and its passenger up; This energy is lost when the car goes down with its own weight. The high current attraction of the pump at startup also places higher demands on the building's electrical system. There is also an environmental problem that must lift the leaking fluid of the cylinder into the ground.
The modern generation of low cost, engine space-less traction lift is made possible by advancements in traction motor miniaturization and control systems challenging the supremacy of hydraulic lifts in their traditional market niche.
Electromagnetic Propulsion
The cable-free elevator using an electromagnetic drive, capable of moving vertically and horizontally, has been developed by the German engineering firm Thyssen Krupp for use in high and high density buildings.
Hiking elevator
The climb elevator is a self-ascending elevator with its own propulsion. Drives can be made by an electric or combustion engine. Climbing lifts are used in pole or maned towers, for easy access to parts of this construction, such as flight safety lights for maintenance. An example is the Moonlight tower in Austin, Texas, where the elevator only accommodates one person and equipment for maintenance. The Glasgow Tower - an observation tower in Glasgow, Scotland - also uses two climbing lifts.
Pneumatic elevator
This kind of elevator uses a vacuum above the cab and the valve at the top of the "axis" to move the cabin up and close the valve to keep the cabin at the same level. A diaphragm or piston is used as a "brake", if there is a sudden increase in pressure above the cab. To descend, it opens the valve so that air can hit the top of the "axis", allowing the cabin to drop by its own weight. This also means that if a power failure occurs, the cabin will automatically drop. The "shaft" is made of acrylic, and is always round due to the turbine shape of the vacuum pump. To keep the air inside the cabin, rubber seals are used. Due to technical limitations, these lifts have low capacity, they usually allow 1-3 passengers and up to 525 pounds.
Control the elevators
Manual control
In the first half of the twentieth century, almost all elevators did not have an automatic position from the floor where the taxi stopped. Some older freight lifts are controlled by switches operated by pulling adjacent straps. In general, most elevators before World War II are manually controlled by elevator operators using a rheostat connected to the motor. This rheostat (see picture) is flanked in a cylindrical container about the size and shape of the cake. It is mounted upright or sideways on the cabin wall and operated through a projecting handle, which is capable of gliding around the top of the cylinder.
The motor lift is located at the top of the shaft or next to the bottom of the shaft. Pushing the handle forward will cause the cabin to rise; retreat will make it sink. The harder the pressure, the faster the elevator will move. The handle also functions as a human dead switch: if the operator releases the handle, it will return to its upright position, causing the elevator cabin to stop. In time, interlock security will ensure that the inside and outside doors are closed before the elevator is allowed to move.
This lever will allow control of the energy supplied to the motor thus allowing the elevator to be positioned accurately - if the operator is skilled enough. More specifically, the operator must "jog" the controls, moving the cabs bit by bit until the elevator is close enough to the landing point. Then the operator will direct the incoming and outgoing passengers to "keep track of the steps".
Automatic lifts began to emerge in the early 1930s, their development accelerated by elevator operators who brought large cities hanging on skyscrapers (and therefore their lifts) like New York and Chicago to their knees. This electromechanical system uses a relay logic circuit that increases the complexity to control the speed, position and operation of elevator doors or bank lifts.
The early 1950s Otis Autotronic System brought the earliest prediction system that could anticipate traffic patterns inside the building to spread the elevator movement in the most efficient way. Relay-controlled elevator systems remained common until the 1980s and their gradual replacement with microprocessor-based solid-state controls is now an industry standard. Most manually operated elevators have been installed with automatic or semi-automatic controls. General controls
A typical modern passenger elevator will have:
- Room to stand on, fence, pillow seating (luxurious)
- Overloaded sensors - prevent the lift from moving until the overload has been removed. It can trigger a prompt voice alarm or buzzer. It can also trigger the "full car" indicator, indicating the inability of the car to receive more passengers until some are dismantled.
- Electric fans or air conditioning units to improve circulation and comfort.
- Control panel with buttons. In the United States and other countries, button and icon text is raised to allow blind users to operate elevators; many of which have Braille text. The buttons include:
- Call key to select floor. Some of them may be a key (to control access). In some elevators, certain floors are inaccessible unless someone is swiping a security card or entering a passcode (or both).
- The door opens and the door closes button.
Operation of transparent open door button, immediately open and hold the door, usually until time runs out and the door closed. The operation of the door closing button is less transparent, and often seems to do nothing, causing frequent but false reports that the door close button is a placebo button: not connected at all, or inactive in normal service. Open doors and door closing buttons are required by code in many jurisdictions, including the United States, specifically for emergency operations: in independent mode, open doors and door close buttons are used to open or close doors manually. Beyond this, programming varies significantly, with some door closing buttons immediately closing the door, but in other cases delayed by the overall time, so the door can not be closed for several seconds after it is opened. In this case (speed up the normal closure), the door close button has no effect. However, the door closing button will cause the hall to be ignored (so the door will not be reopened), and after the time limit expires, the closed door will immediately close the door, for example to cancel the open push of the door. The minimum time limit for automatic door closing in the US is 5 seconds, which is a real delay if not replaced.
- The alarm button or switch, which passengers can use to alert the place manager that they have been trapped inside the elevator.
- A set of locked doors on each floor to prevent accidental access into the elevator rod by unsuspecting individuals. The door is opened and opened by a machine that sits on the roof of the car, which also pushes the doors that travel by car. The door control is provided to close immediately or reopen the door, although the button to close it immediately is often disabled during normal operation, especially on newer elevators. Objects in the moving door lane will be detected by the sensor or physically activate the button that reopens the door. Otherwise, the door will close after the specified time. Some elevators are configured to stay open on the floor until they are asked to move again.
- Elevators in buildings with high traffic often have a "nudge" function (Otis Autotronic system first introduces this feature) that will close the door at reduced speed, and ring a buzzer if the "door" button "open deliberately pressed, or if the door sensor has been blocked for too long.
- The switch stops (not allowed under English rules) to stop the elevator while it is in motion and is often used to hold the elevator when delivery is loaded. Keeping the elevator stopped for too long can trigger an alarm. Unless the local code requires otherwise, it will most likely be a lock button.
Some elevators may have one or more of the following:
- Telephone elevators, which can be used (other than alarms) by stuck passengers for help. It may consist of a transceiver, or just a button.
- Hold the button: This button delays door closing time, useful for loading cargo and hospital beds.
- Call revocation: The destination floor may not be selected by double clicking.
- Access restricted by key switch, RFID reader, code keypad, hotel room card, etc.
- One or more additional door sets. It's mainly used to serve different floor plans: on each floor only a set of open doors. For example, in an elevated crossing arrangement, the front door can open on the road surface, and the rear door opens at the crossing level. It's also common in garages, train stations, and airports. Or, both doors can open on the given floor. This is sometimes the time so that one side opens first to get off, and then the other side is open to get, to increase boarding/exit speed. This is particularly useful when passengers have luggage or trains, such as at the airport, because of reduced maneuverability.
- In the case of double doors, there may be two sets of Doors open and Door closing buttons, with one pair controlling the front door, from the console's point of view, usually denoted & lt; & gt; and & gt; & lt;, with another pair controlling the back door, usually marked with a center line, & lt; | & gt; and & gt; | & lt ;, or double line, | & lt; & gt; | and & gt; || & lt;. This second set is required in the US if both doors can be opened on the same landing, so both doors can be controlled in independent service.
- Security camera
- Plain walls or mirrored walls.
- The windowpane glass provides an interior view of the building or onto the streets.
The audible signaling button, labeled "S": in the US, for elevators installed between 1991 and 2012 (the beginning of ADA and coming into effect in 2010 revisions), buttons that if pressed sound an audible signal as each floor is passed, to help passengers with visual impairments. No longer used on new elevators, where the sound is mandatory.
Other controls, which are generally inaccessible to the public (either because they switch keys, or because they are stored behind locked panels), include:
- Fire service, phase 2 switches
- Switch to turn on or off the elevator.
- The inspector switch, which puts the lift in inspection mode (this may be located above the elevator)
- Manual up/down control for elevator technicians, for use in inspection mode, for example.
- Exclusive exclusive / exclusive Service (also known as "Car Preferences"), which will prevent the car from answering phone calls and only up to the selected floor through the panel. The door must remain open while parked on the floor. This mode can be used to transport temporary goods.
- Service officer mode.
- Large buildings with multiple elevators of this type also have stop operators placed in the lobby to direct passengers and signal the operator to leave by using a cricket mechanical mistake maker.
External control
Elevators are usually controlled from the outside by the call box, which has the up and down buttons, at each stop. When pressed on a certain floor, the keys call the elevator to pick up more passengers. If a dedicated elevator currently serves traffic in a particular direction, it will only answer calls in the same direction unless there are no more calls outside that floor.
In groups of two or more elevators, the call button can be connected to a central delivery computer, as it is illuminated and canceled together. This is done to ensure that only one car is called at a time.
The key switch can be installed on the ground floor so that the lift can be switched on or off from the outside.
In a destination control system, a person chooses the intended destination floor (in lieu of pressing "on" or "down" ) and then being told which elevator will serve their request.
Floor numbering
elevator algorithm
The elevator algorithm, a simple algorithm that can be used by a single elevator to decide where to stop, is summarized as follows:
- Continue traveling in the same direction while there are remaining requests in the same direction.
- If there is no further request in that direction, stop and silence, or change direction if there is a request in the opposite direction.
The elevator algorithm has found an application in the computer's operating system as an algorithm for scheduling hard disk requests. The modern elevators use a more complex heuristic algorithm to decide what demand for the next service. An introduction to this algorithm can be found in "Elevator traffic handbook: theory and practice" given in the references below.
Destination control system
Some skyscrapers and other types of installations have a destination operating panel where passengers register their floor calls before entering the car. This system allows them to know which car to wait for, rather than everyone who gets into the next car. In this way, travel time is reduced because the elevator stops less for individual passengers, and the computer distributes adjacent stops to various cars in the bank. Although travel time is reduced, waiting time for passengers may be longer because they do not need to allocate the next car to depart. During peak periods down, the benefits of goal control will be limited because passengers have the same goal.
This can also improve accessibility, since mobility-impaired passengers can move to their designated car before.
In the elevator there is no call button to push, or the buttons are there but they can not be pushed - except open the door and alarm button - they just show the floor stop.
The goal control idea was originally conceived by Leo Port of Sydney in 1961, but by then the elevator controllers were implemented in relays and could not optimize the performance of the allocation of destination controls.
The system was first spearheaded by Schindler Elevator in 1992 as Miconic 10. The manufacturer of the system claims that the average travel time can be reduced by up to 30%.
However, performance improvements can not be generalized because the benefits and limitations of the system depend on many factors. One of the problems is that the system is subject to the game. Sometimes, one person enters a destination for a large group of people who go to the same floor. Delivery algorithms usually can not fully meet the variations, and late people may find elevators assigned to them already full. Also, sometimes, one person can hit the floor several times. This is common with the up/down buttons when people believe this to be an effective way to speed up the elevator. However, this will make the computer think many people are waiting and will allocate an empty car to serve this one person.
To prevent this problem, in a single destination control implementation, each user is assigned an RFID card, for identification and tracking, so the system knows each user's call and can cancel the first call if the passenger decides to travel to another destination, preventing empty calls. Recent discoveries know even where people are and how many on the floor are due to their identification, whether for evacuation purposes or for security reasons. Another way to prevent this problem is to treat everyone who travels from one floor to another as a group and only allocates one car for the group.
The same purpose scheduling concept can also be applied to public transport as in fast transit groups.
Custom operating mode
Anti-crime protection
The anti-crime protection feature (ACP) will force every car to stop at a predetermined landing and open its door. This allows the security guard or receptionist on the landing to visually check passengers. The car stops at this landing as it passes to serve further requests.
Rise to the top
During the peak-ride mode (also called moderate incoming traffic), the group lift carriages are pulled into the lobby to provide quick service to passengers arriving at the building, usually in the morning when people arrive for work or at the end of the lunch time period. Elevators are sent one by one when they reach a predetermined passenger load, or when the door is opened for a certain period of time. The next elevator to be shipped usually has a hall lantern or the sign of "this next departing car" illuminated to encourage passengers to maximize the use of available elevator system capacity. Some elevator banks are programmed so at least one car will always return to the lobby floor and parking whenever it becomes free.
The commencement of up-peak can be triggered by time clock, with the departure of a number of fully loaded cars leaving the lobby within a certain period of time, or with a switch operated manually by the building attendant.
Down peak
During down-peak mode, in-group car lifts are sent away from the lobby to the highest floor served, after which they start running down the floor in response to the hall calls placed by passengers who want to leave the building. This allows the elevator system to provide maximum passenger handling capacity for people leaving the building.
The commencement of down-peak can be triggered by the time clock, with the arrival of a number of fully loaded cars in the lobby within a certain period of time, or with a switch operated manually by the building attendant.
Sabbath service
In areas with large devoted Jewish populations or in facilities serving Jews, one can find "Sabbath lifts". In this mode, the elevator will stop automatically on every floor, allowing people to enter and exit without having to press any button. This prevents the violation of the Sabbath restrictions on the operation of the electrical devices when the Sabbath applies to those observing this ritual.
However, the Sabbath mode has large amounts of energy use side effects, running elevator cars sequentially up and down on each floor of the building, repeatedly servicing on the floor unnecessary. For tall buildings with multiple floors, the car must move on a fairly frequent basis so as not to cause undue delay for potential users who will not touch the controls as it opens doors on every floor above the building.
Some tall buildings may have replacement Sabbath substitutes to save time and energy; for example, the elevator may stop only on the even-numbered floors on the way up, and then the odd-numbered floors on the way down.
Independent service
Independent service is a special service mode found in most elevators. It is activated by a keylock inside the elevator itself or in a centralized control panel in the lobby. When the elevator is placed on an independent service, it will no longer respond to the call of the hall. (In the elevator bank, traffic is flown to another elevator, while in one elevator, the hall button is disabled). The elevator will remain parked on the floor with the door open until the floor is selected and the door close button is held until the elevator starts to run. Self-service is useful when transporting large items or moving groups of people between certain floors.
Inspection service
The inspection service is designed to provide access to hoistways and top cars for inspection and maintenance by quality elevator mechanics. This is first activated by the primary button on the car's operating panel typically labeled 'Inspection', 'Top Car', 'Active Access' or 'HWENAB' (short for Access HoistWay ENABled). When the switch is activated, the elevator will stop if it moves, the car call will be canceled (and the key is deactivated), and the hall call will be given to another elevator car in the group (or canceled in a single lift configuration). The elevator can now only be moved by an appropriate 'Access' key switch, usually located at the highest part (for accessing the top of the car) and lowest (for accessing the elevator hole) of the landing. The access key switch will allow the car to move with reduced inspection speeds with open hoistway doors. This speed can range from anywhere up to 60% of the normal operating speed on most controllers, and is usually determined by the local security code.
Elevator has a car top inspection station that allows the car to be operated by a mechanic to move it through a hoistway. Generally, there are three buttons: UP, RUN, and DOWN. Both RUN and directional keys must be held to move the car in that direction, and the elevator will stop moving as soon as the button is released. Most other elevators have a toggle switch and a RUN button. The inspection panel also has a standard power outlet for work lights and powered appliances.
Fire service
Depending on the location of the lift, the fire service code will vary from state to state and other countries. Firefighting services are usually divided into two modes: phase one and phase two. This is a separate mode that can enter the elevator.
Phase one mode is activated by a suitable smoke sensor or heat sensor inside the building. As soon as the alarm is activated, the lift will automatically go into phase one. The elevator will wait some time, then proceed to nudging mode to let everyone know that the elevator is leaving the floor. Once the elevator has left the floor, depending on where the alarm goes, the elevator will go to the fire extinguisher floor. However, if the alarm is activated on the fire extinguishers, the elevator will have an alternate floor to be recalled. When the elevator is pulled back, he heads to the recall floor and stops with the door open. The elevator will no longer respond to calls or move in any direction. Located on the fire extinguisher floor is a fire lock switch. The fire service fire switch has the ability to turn off the fire service, turn on the fire service or to bypass the fire service. The only way to return the elevator to normal service is to change it to skip after the alarm is reset.
Two-phase mode can only be activated by a lock button located inside the elevator on a centralized control panel. This mode is made for firefighters so they can save people from burning buildings. The two phase phase locks located in COP have three positions: dead, alive, and hold. By activating phase two, firefighters allow the car to move. However, like self-service mode, the car will not respond to car calls unless the firefighter manually pushes and holds the door close button. As soon as the elevator gets to the desired floor, it will not open the door unless the fireman keeps the door button open. This is if the floor is on fire and firefighters can feel the heat and do not know to open the door. The fire department should hold the door until the door is completely open. If for whatever reason the firefighters want to leave the elevator, they will use a hold position on the lock button to ensure the lift stays on that floor. If firefighters want to return to the recall floor, they simply turn off the lock and close the door.
Emergency/medical code-blue service
Generally found in hospitals, the blue-code service allows lifts to be called to any floor for use in emergency situations. Each floor will have a blue key lock button, and when activated, the elevator system will soon choose the fastest responding elevator car, regardless of the direction of the ride and passenger load. Passengers inside the elevator will be notified with alarm and indicator lights to exit the elevator when the door is open.
Once the elevator arrives on the floor, it will park with its doors open and the car keys will be disabled to prevent passengers from controlling the elevators. The medical personnel then have to activate the blue-code lock key in the car, select their floor and close the door with the door closing button. The elevator will then travel non-stop to the selected floor, and will remain in the blue-code service until it is turned off in the car. Some hospital elevators will display a hold position on the blue key (similar to the fire service) which allows the lift to remain on the floor locked outside the service until the blue code is deactivated.
Riot mode
In the event of civil disturbance, rebellion or riot, management may prevent the elevator from stopping in the lobby or parking area, preventing unwanted people from using elevators while still allowing tenants to use buildings throughout the building.
Emergency power operation
Many elevator installations now have emergency power systems that allow the use of elevators in dark situations and prevent people from getting stuck in elevators.
Traction elevators
When power is lost in the traction lift system, all lifts will initially stop. One by one, every car in the group will return to the lobby floor, open the door and close. People in the remaining elevators can see the indicator lights or hear a voice announcement telling them that the elevator will be back in the lobby soon. After all cars are successfully restored, the system will automatically select one or more cars to be used for normal operation and these cars will resume operations. Cars selected to operate under emergency power can be manually overwritten by button or strip switch in the lobby. To help prevent the trap, when the system detects that the power is running low, it will take the car that runs into the nearest lobby or floor, opening the door and closing.
Hydraulic elevators
In a hydraulic lift system, emergency power will lower the lift to the lowest landing and open the door to allow passengers out. The doors are then closed after a period of time that can be adjusted and the car remains unusable until reset, usually by turning the main power switch elevator. Typically, due to high current draw when starting the pump motor, hydraulic lifts are not run using standard emergency power systems. Buildings such as hospitals and nursing homes typically measure their emergency generators to accommodate this draw. However, the increasing use of current-limiting driving motors, commonly known as "soft-start" contactors, avoids many of these problems, and pump current withdrawal is less of a limiting concern.
Modernization of elevators
Most elevators are built to provide about 30 to 40 years of service, as long as service intervals are determined and periodic maintenance/inspections by the factory are followed. As age and elevator equipment become increasingly difficult to find or replace, as the code changes and driving performance worsen, a total elevator overhaul can be suggested to the building owner.
Typical modernization consists of controlling equipment, power lines and switches, position and direction indicators, wind and motor (including door operators), and sometimes door-hanger tracks. Rarely sling cars, rails, or other heavy structures change. The cost of modernizing an elevator can vary greatly depending on the type of equipment to be installed.
Modernization can greatly improve operational reliability by replacing mechanical relays and contacts with solid-state electronics. Driving quality can be improved by replacing motor-based hard disk design with Variable-Voltage drives, Variable Frequency (V3F), providing almost unimpeded acceleration and deceleration. Passenger safety is also enhanced by updating systems and equipment to match the current code.
Security elevator
Lifting Elevator cable
Speaking statistically, the cable-voltage lifts are very safe. Their safety record is unmatched by other vehicle systems. In 1998, it was estimated that about eight million one percent (1 of twelve million) elevator rides produced anomalies, and most of these were small things like doors that failed to open. From 20 to 30 elevator-related deaths each year, most are related to maintenance - for example, technicians lean too deep into axis or trapped between moving parts, and most of the rest are associated with other types of accidents. , like people stepping blindly through doors that open to empty holes or strangled by a scarf caught in the door. In fact, before the September 11 terrorist attacks, the only known free fall incident in modern cable lifts occurred in 1945 when an B-25 bomber hit the Empire State Building in a fog, cutting a cable from an elevator elevator, which fell off the floor 75 to the bottom of the building, seriously injure (though not kill) the only occupant - the elevator operator. However, there was an incident in 2007 at Seattle's children's hospital, where ISIS ThyssenKrupp's free-space machine-less free lift fell until the security brake got engaged. This is due to a defect in the design where the cables are connected at one point in common, and the kevlar strap has a tendency to overheat and cause a slip (or, in this case, free fall). Although it is possible (though highly unlikely) for lift cables to snap, all lifts in the modern era have been equipped with some security devices that prevent the lifts from just falling free and crashing. Taxi lifts are typically borne by 2 to 6 (up to 12 or more in high-rise installations) or hoist cables, each of which is capable of supporting the full elevator load plus twenty-five percent heavier. In addition, there are devices that detect whether the elevator is down faster than the maximum designed speed; If this happens, the device causes copper (or silicon nitride at high increment installation) brake shoes to clamp along the vertical rails on the shaft, stop the lift quickly, but not so suddenly to cause injury. This tool is called the governor, and was created by Elisha Graves Otis. In addition, oil/hydraulic or springs or polyurethane or telescopic oils/hydraulic or combination buffers (depending on trip height and travel speed) are mounted at the bottom of the shaft (or at the bottom of the cab and sometimes at the top of the cabin or shaft) give any effect. However, In Thailand, in November 2012, a woman was killed in a free fall elevator, in what was reported as "the first legally recognized death caused by falling decline".
Hydraulic elevators
Previous problems with hydraulic elevators include the destruction of underground electrolytes against cylinders and bulkheads, pipe failure, and control failures. Single insulation cylinders, usually made prior to a breastmilk change A17.1 Safety Elevators 1972 requiring a second sealed plug, may experience catastrophic failure. Previous code only allows one-bottom hydraulic cylinder. In the event of a cylinder violation, fluid loss causes the movement of an uncontrolled elevator. This creates two significant dangers: impacts at the bottom when the lift stops abruptly and is at the entrance for shear potential if the rider is partially in the elevator. Since it is not possible to verify the system at any time, this code requires periodic stress testing capabilities. Another solution to protect against a cylinder blowout is to install a plunger grip device. Two commercially available are known as "LifeJacket" and "HydroBrake" marketing. The plunger gripper is a device that, in the event of uncontrolled downward acceleration, unconsciously holds the plunger and stops the car. A device known as an excessive or cracked velocity valve is attached to the cylinder's hydraulic inlet/outlet and adjusted for maximum flow rate. If the pipe or hose is ruptured (broken), the flow rate of the broken valve will exceed the set limit and mechanically stop the flow of hydraulic fluid outlet, thus stopping the plunger and the car downward.
In addition to safety concerns for older hydraulic lifts, there is a risk of leaking hydraulic oils to the aquifer and causing potential environmental contamination. This led to the introduction of PVC liners (casing) around the monitored hydraulic cylinder for integrity.
In the last decade, the latest innovations in inverted hydraulic jacks have removed expensive drilling processes to install drill holes. It also eliminates corrosion threats to the system and improves security.
Mine shaft elevators
Routine mine rail safety testing is routinely conducted. This method involves testing damaging a cable segment. The ends of the segment are frayed, then arranged in a conical zinc mold. Each end of the segment is then secured in a large hydraulic stretching machine. This segment is then placed under an increased load to the point of failure. Data on elasticity, load, and other factors are compiled and reports are generated. This report is then analyzed to determine whether the entire rail is safe to use or not.
Use of elevators
Passenger service
The passenger elevator is designed to move people between floors of buildings.
Capacity of passenger elevators related to available floor space. Generally passenger lifts are available in capacities ranging from 500 to 2,700 kg (1,000-6,000 pounds) with an increase of 230 kg (500 pounds). Generally passenger elevators in buildings eight floors or less are hydraulic or electric, which can reach speeds up to 1 m/s (200 ft/min) hydraulically and up to 152 m/min (500 ft/min) of electricity. In buildings up to ten floors, electric and toothless elevators tend to have speeds of up to 3 m/s (500 m ft/min), and above ten floors ranging from 3 to 10 m/s (500-2,000 ft/min).
Sometimes passenger lifts are used as city transportation along with funiculars. For example, there is a 3-station underground public elevator in Yalta, Ukraine, which carries passengers from a hilltop over the Black Sea where the hotel perches, to a tunnel located on the beach below. At Casco Viejo station in Metro Bilbao, the lift that provides access to the station from the hilltop settlement doubles as a city transport: the station ticket constraints are arranged so that passengers can pay to reach the elevators from the lower city entrance, or vice versa. See also Elevator for urban transport.
Type of passenger elevator
Passenger elevators can be devoted to services they do, including: hospital emergency (blue code), front and rear entrance, television in multi-storey buildings, level boards, and other uses. Cars can be ornate in interior appearance, may have audio visual advertisements, and can be provided with a special recorded voice announcement. Elevators may also have loudspeakers in them to play quiet and easy to listen music. Such music is often referred to as elevator music.
The express elevator does not serve all floors. For example, move between the ground floor and the skylobby, or move from the ground floor or skylobby to various floors, passing the floor between the two. It is very popular in East Asia.
Capacity
Residential elevators may be small enough to accommodate only one person while some are large enough for more than a dozen. Wheelchairs, or platform lifts, a special type of elevator designed to drive a wheelchair of 3.7 m (12 feet) or less, can often accommodate only one person in a wheelchair at the same time as a 340 kg (750 lb) load.
Elevator stuff
Goods elevator, or freight elevator, is an elevator designed to carry goods, not passengers. Elevator items are usually required to display written notice in the car that passenger use is prohibited (though not always illegal), although certain freight lifts allow double use through the use of inconspicuous risers. In order for the elevator to be legal to transport passengers in some jurisdictions, it must have a sturdy inner door. Cargo lifts are usually larger and capable of carrying heavier loads than passenger lifts, generally from 2,300 to 4,500 kg. Cargo lifts may have manually operated doors, and often have rough interior finishes to prevent damage when loading and unloading. Although hydraulic cargo lifts exist, electric elevators are more energy efficient for freight work.
The pavement elevators
Sidewalk elevator is a special type of freight elevator. Sidewalk pavements are used to move material between dungeons and ground-level areas, often on sidewalks outside the building. They are controlled through exterior buttons and emerging from metal trap doors at ground level. The sidewalk lift car has a unique shaped top that allows this door to open and close automatically.
Rapture stage
The rapture stage and the orchestra appointment are special elevators, usually powered by hydraulics, used to raise and lower the entire stage of the theater. For example, Radio City Music Hall has four such elevators: an orchestra elevator that includes a large stage area, and three smaller elevators near the back of the stage. In this case, the orchestra appointment is strong enough to raise the entire orchestra, or all players (including live elephants) up to stage stage from below. There is a barrel in the background of the left image that can be used as a scale to represent the size of the mechanism
Vehicle elevator
Vehicle elevators are used inside buildings or areas with limited space (in gentle spaces), generally to move the car to a parking garage or a manufacturer's storage. Hydraulically driven chains (unlike bicycle chains) produce elevators for platforms and no counterweight. To accommodate building design and improve accessibility, platforms can rotate so drivers only have to drive forward. Most vehicle elevators have a 2 ton capacity.
Examples of rare extra-heavy elevators for 20 ton trucks, and even for trains (as used at Kiev's Dnipro Metro Station)
Source of the article : Wikipedia
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