Elevator

A set of elevators or lifts, in the lower level of a train station. The arrows indicate each elevator's position and direction of travel. The elevator on the right is preparing to ascend, and the left elevator is descending from the top floor (or is about to).

An elevator is a transport device used to move goods or people vertically. Outside North America, elevators are known more commonly as lifts. Other languages may have loanwords based on either elevator (e.g. Japanese) or lift (e.g. Cantonese). Because of wheelchair access laws, elevators are often a requirement in new buildings with multiple floors.

Design

Elevators began as simple rope or chain hoists. An elevator is essentially a platform that is either pulled or pushed up by a mechanical means. A modern day elevator consists of a cab (also called a "cage" or "car") mounted on a platform within an enclosed space called a shaft or more correctly a "hoistway". In the past elevator drive mechanisms were powered by steam and water hydraulic pistons.

In a "traction" elevator, cars are pulled up by means of rolling steel ropes over a deeply grooved pulley, commonly called a sheave in the industry. The weight of the car is balanced with a counterweight. Sometimes two elevators move always synchronizedly in opposite direction, and they are each other's counterweight.

The friction between the ropes and the pulley furnishes the traction which gives this type of elevator its name.

Hydraulic elevators use the principal of hydraulics to pressurize an above ground or in-ground piston to raise and lower the car. Roped Hydraulics use a combination of both ropes and hydraulic power to raise and lower cars. Recent innovations include permanent earth magnet motors, machine room-less rail mounted gearless machines, and microprocessor controls.

Which technology is used in new installations depends on a variety of factors. Hydraulic elevators are cheaper, but installing cylinders greater than a certain length becomes impractical for very high lift hoistways. For buildings of much over seven stories, traction elevators must be employed instead. Hydraulic elevators are usually slower than traction elevators.

History

Elisha Otis's elevator patent drawing, 15 January 1861.

In 1823, an "ascending room" made its debut in London. [1]

In 1853, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. The design of the OTIS safety is somewhat similar to one type still used today. It consists of knurled roller(s) that lock the elevator to its guides should the elevator descend at an excessive speed, which is monitored by a governor device.

On March 23, 1857 the first Otis elevator was installed at 488 Broadway in New York City. The first elevator shaft preceded the first elevator by four years. Construction for Peter Cooper's Cooper Union building in New York began in 1853. An elevator shaft was included in the design for Cooper Union, because Cooper was utterly confident a safe passenger elevator would soon be invented; the shaft however was circular because Cooper felt it was the most efficient design. Later Otis designed a special elevator for the school. Today the Otis Elevator Company, now a subsidiary of United Technologies Corporation, is the world's largest manufacturer of vertical transport systems, followed by Schindler, Thyssen-Krupp and Kone, in order.

The first electric elevator was built by Werner von Siemens in 1880. The safety and speed of electric elevators were significantly enhanced by Frank Sprague.

The development of elevators was led by the need for movement of large amounts of raw materials including coal and lumber from hillsides. The technology developed by these industries and the introduction of steel beam construction worked together to provide the need for the passenger and freight elevators we use today.

In October 11, 1887 Alexander Miles, an African American inventor, patented a method which permitted elevator doors to open and close safely.

Modern elevator construction

Today, elevators are built under strict supervision of the Building Codes. Model Codes which are the standard in most US jurisdictions require compliance with the American Society of Mechanical Engineers' (ASME) standards for the installation, maintenance, and inspection of elevators. In Canada, the governing authority is the CSA (Canadian Standards Association). In addition other related standards are likely required to be complied with as specified by Local Authorities Having Jurisdiction.

Elevators are generally sold in prepackaged components which are inherently non-proprietary. All of the four major manufacturers sell proprietary microprocessor controls. Each manufacturer provides similar product designs, with differing emphasis on quality, price,or reliablility. In the case of renovations, the use of non-proprietary controls has become a large part of that business because it allows the owner to offer the maintenance contract to multiple bidders rather than accept a single manufacturer for the life of the elevator which can be more than 30 years. In some large campus type properties, the use of non-proprietary equipment in new construction has replaced the standard prepackaged product. Non-proprietary systems generally have a higher up front cost, but may be offset by allowing the owner to control the long term costs over the life of the elevator.

A scenic elevator in action.

In some locations, the shaft and parts of the cab are made of transparent material for specialized "Scenic elevators." This allows riders to see outside the cab as they travel on the elevator. Some locations take advantage of this transparent material by placing the elevators along the walls of their building. This allows riders to see the outdoor environment as the cab runs along the side of the buildings. An example of this is the CN Tower in Toronto, Canada.

Today, all new elevators are computer-controlled and microprocessor based. This allows the elevator system to place cabs where they are most needed in the interest of smooth running, with behavior based on analysis of building use called "Traffic Studies." Traffic Studies are done by professional elevator consultants who use specialized tools to determine the optimum size, speed and number of elevators for a building based on its peak use periods. Computer control also permits greater control of access to various floors of a building after hours and on weekends. Methods of access control include card readers, keys, and access codes entered into the control panel of the elevator.

Elevators are usually installed in a building during construction. Renovations (mostly referred to as Modernizations in the industry) may consist of replacements for hoistway (floor landing) doors, car doors, interior cab finishes, controls, all hoistway wiring and cab wiring, hoist machines, governors, hydraulic pistons and hall fixtures. At times renovations may also include replacement of the entire cab itself. In many instances the upgrading of components may require additional code compliance.

Elevator safety

Elevators are characterized as being extremely safe. Indeed, their safety record, that of moving millions of passengers every day, with extremely low rate of incident, is unsurpassed by any other vehicle system, although fatalities due to malfunction http://www.yomiuri.co.jp/dy/national/20060605TDY02005.htm have been known to occur on occasion.http://www.yomiuri.co.jp/dy/national/20060605TDY02005.htm A certain number of passengers do die every year in elevator related incidents.McCann, M. "Deaths and Injuries Involving Elevators and Escalators - A Report of the Center To Protect Workers' Rights (Revised)",2004. http://www.cdc.gov/elcosh/docs/d0300/d000397/d000397.html In 1998, in the United States, it was reported that of the estimated 120 billion rides per year in the approximately 600,000 elevators in the U.S., 10,000 people wound up in the emergency room.Good Housekeeping, "The last word on elevator safety", 1998 http://eesf.org/safetrider/article1.htm because of elevator-related accidents. "Statistically, it's a safe ride", says Ray Lapierre, executive director of the Elevator Escalator Safety Foundation.

Past problems with hydraulic elevators meant it was found such elevators that were built prior to a code change in 1972 were found to be subject to possible catastrophic failure. The code had previously required only single-bottom hydraulic cylinders; in the event of a breach of the cylinder, an uncontrolled fall of the elevator might result. Because it is impossible to verify the system completely without a pressurized casing (as described below), it is necessary to remove the piston to inspect it. The cost of removing the piston is such that it makes no economical sense to re-install the old cylinder, and therefore it is necessary to replace the cylinder and install a new piston.

In addition to the safety concerns for older hydraulic elevators, there is risk of leaking hydraulic oil into the aquifer and causing potential environmental contamination. This has led to the introduction of PVC liners (casings) around hydraulic cylinders which can be monitored for integrity.

In the past decade, recent innovations called machine room-less elevators first developed by Kone called the EcoSpace http://sweets.construction.com/mfg/794/P7380.htm, have reduced the amount of overhead machinery required (the main disadvantage of traction elevator) are gradually making hydraulic elevators obsolete. Today, MRL elevator models include the Kone EcoSpace, Mitsubishi ELENESSA, Otis Gen2, Fujitec Talon, ThyssenKrupp ISIS 2 and the Schindler 400A models. In Hong Kong, few hydraulic elevators remain and most companies only do hydraulic elevators as a special order. While the new machine room-less have proved good for space, a few companies have experienced major problems with quality control, such as limited travel to 300 feet with 40 floors, and engineering design when it comes to maintenance and replacement parts.

Uses of elevators

Passenger service

A Passenger lift is designed to ferry people from point A to Point B vertically. The modern passenger lift is a simple means of transport within a building. This apparent simplicity belies a complex and sophisticated mechanical, electrical and microelectronic system.

Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in typical capacities from 2,000 to 5,000 lb (455 to 2,720 kg) in 500 lb (230 kg) increments. Generally passenger elevators in buildings eight floors or less are hydraulic. In buildings up to ten floors, electric elevators are likely to have speeds up to 500 ft/min (2.5 m/s), and above ten floors speeds begin at 500 ft/min (2.5 m/s) up to about 2000ft/min (10 m/s).

Sometimes passenger elevators used as a city transport along with funiculairs. For example, there is a 3-station underground public elevator in Yalta drilled in a rock with the lowest station located on the seabeach.

Types of passenger elevators

The former World Trade Center's twin towers were the first supertall buildings to use skylobbies, located on the 44th and 78th floors of each tower.

Passenger elevators may be specialized for the service they perform, including: Hospital emergency (Code blue), front and rear entrances, double decker, and other uses. Cars may be ornate in their interior appearance, may have audio visual advertising, and may be provided with specialized recorded voice instructions.

An express elevator does not serve all floors. For example, it moves between the ground floor and a skylobby, or it moves from the ground floor or a skylobby to a range of floors, skipping floors in between.

Entrapment

The concern for entrapping passengers requires all elevators to have communication connection to an outside 24 hour emergency service, automatic recall capability in a fire emergency, and special access for fire fighters' use in a fire. Elevators should not be used by the public if there is a fire in or around the building. Numerous building codes requires signs near the elevator to state "USE STAIRS IN CASE OF FIRE".

Capacity

Residential elevators may be small enough for one person while some are large enough for more than a dozen.Wheelchair, or platform lifts, a specialized type of elevator designed to move a wheelchair 6 ft (2 m) or less, often can accommodate just one person in a wheelchair at a time with a maximum load of 750 lb (340 kg).

Freight elevators

Old Elbe Tunnel vehicle lift

A freight elevator (or goods lift) is an elevator designed to carry goods, rather than passengers. Freight elevators are often exempt from some code requirements. Freight elevators or service elevators (goods or service lifts) may be exempt from some of the requirements for fire service. However, new installations would likely be required to comply with these requirements. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited, though certain freight elevators allow dual use through the use of an inconspicuous riser.Freight elevators are typically larger and capable of carrying heavier loads than a passenger elevator, generally from 2,300 to 4,500 kg. Freight Elevators may have manually operated doors, and often have rugged interior finishes to prevent damage while loading and unloading. Although hydraulic freight elevators exist, electric elevators are more energy efficient for the work of freight lifting.

Stage and Orchestra lifts are specialized lifts for use in the performing arts, and are often exempt from some requirements. Local jurisdictions may govern their use, installation and testing, however they are often left out of local code enforcement provisions due to their infrequent installation.

Vehicle elevators

A car lift is installed where ramps are considered space-inconservative for smaller buildings (usually in apartment buildings where frequent access is not an issue). The car platforms are raised and lowered by chained steel gears (resembling bicycle chains in appearance). In addition to the vertical motion, the platforms can rotate about its vertical axis (up to 180 degrees) to ease driver access and/or accommodate building plans. Most parking lots of this type are however unable to accommodate taller vehicles, like SUVs.

In spite of the sheer size of the car platform and its perceived "passenger capacity", there are huge passenger and freight lifts that can accommodate more than the rated capacity of the car lift.

Aircraft elevators

On aircraft carriers, elevators carry airplanes and helicopters from the flight deck to the hangar deck and vice versa for operations or for repairs. These elevators are designed for much greater capacity than any other elevator ever built, designed to carry up and down up to 200,000 pounds of tactical aircraft and equipment at a time. Smaller elevators lift munitions and missiles to the flight deck from magazines protected deep inside the ship.

Dumbwaiter

A small freight elevator is often called a dumbwaiter, often used for the moving of small items such as dishes in a 2-story kitchen or books in a multi-story rack assembly. Passengers are never permitted on dumbwaiters. Dumbwaiters are required to comply with ASME A18.1 in most US and Canadian Jurisdictions.

Dumbwaiters are generally driven by a small electric motor with a counterweight and their capacity is limited to about 750 lb (340 kg). They may also be hand operated using a roped pulley. Dumbwaiters are used extensively in the restaurant business (hence the name) and may also be used as book lifts in libraries, or to transport mail or similar items in an office tower. They can withstand heavy loads of up to 800 lb, that comply with the ASME A18.2.

Material handling belts

A different kind of elevator is used to transport material. It generally consists of an inclined plane on which a conveyor belt runs. The conveyor often includes partitions to prevent the material from sliding backwards. These elevators are often used in industrial and agricultural applications.When such mechanisms (or spiral screws or pneumatic transport) are used to elevate grain for storage in large vertical silos, the entire structure is called a grain elevator.

Types of elevator hoist mechanisms

Elevator in a hospital

In general, there are three means of moving an elevator:

Traction elevators

Geared and gearless traction elevators Geared Traction machines are driven by AC or DC electric motors. Geared machines use worm gears to mechanically control movement of elevator cars by "rolling" steel hoist ropes over a drive sheave which is attached to a gearbox driven by a high speed motor. These machines are generally the best option for basement or overhead traction use for speeds up to 1000 ft/min (5 m/s).Gearless Traction machines are high speed, low torque electric motors powered by AC or DC. In this case, the drive sheave is directly attached to the end of the motor. A brake is mounted between the motor and drive sheave (or gearbox) to hold the elevator stationary at a floor. This brake is usually an external drum type and is actuated by spring force and held open electrically; a power failure will cause the brake to hold the elevator in position.In each case, cables are attached to a hitch plate on top of the cab or may be "underslung" below a cab, and then looped over the drive sheave to a counterweight attached to the opposite end of the cables which reduces the amount of power needed to move the cab. The counterweight is located in the hoist-way and rides a separate rail system; as the car goes up, the counterweight goes down, and vice versa. This action is powered by the traction machine which is directed by the controller, typically a relay logic or computerized device that directs starting, acceleration, deceleration and stopping of the elevator cab. The weight of the counterweight is typically equal to the weight of the elevator cab plus 40-50% of the capacity of the elevator. The grooves in the drive sheave are specially designed to prevent the cables from slipping. "Traction" is provided to the ropes by the grip of the grooves in the sheave, thereby the name. As the ropes age and the traction grooves wear, some traction is lost and the ropes must be replaced and the sheave repaired or replaced. Some elevators have a system called compensation. This is a separate set of cables or a chain attached to the bottom of the counterweight and the bottom of the elevator cab. This makes it easier to control the elevator because the weight will fluctuate less over the entire system. If the elevator cab is at the top of the hoist-way, there is a short length of hoist cable above the car and a long length of compensating cable below the car and vice versa for the counterweight. If the compensation is cables there is an additional sheave in the pit below the elevator, to guide the cables. If the compensation is a chain, the chain is guided by a bar mounted between the counterweight rails.

Hydraulic type

Conventional Hydraulic elevators were first developed by Dover Elevator (now a division of ThyssenKrupp Elevator). They are quite common for low and medium rise buildings (2-8 floors) and use a hydraulically powered plunger to push the elevator upwards. On some, the hydraulic piston (plunger) consists of telescoping concentric tubes, allowing a shallow tube to contain the mechanism below the lowest floor. On others, the piston requires a deeper hole below the bottom landing, usually with a PVC casing (also known as a caisson) for protection.

A paternoster in Berlin from the 1970s

Roped hydraulic elevators use a combination of ropes and hydraulics.
Twin post hydraulic
Holeless hydraulic elevators do not require holes to be dug for the hydraulic cylinder. In most designs, the cab is lifted by a pair of hydraulic jacks, one on each side of the elevator.

Climbing elevator

A climbing elevator is a self-ascending elevator with its own propulsion. The propulsion can be done by an electric or a combustion engine. Climbing elevators are used in guyed masts or towers, in order to make easy access to parts of these constructions, such as flight safety lamps for maintenance.

Paternoster

A special type of elevator is the paternoster, a constantly moving chain of boxes. A similar concept moves only a small platform, which the rider mounts while using a handhold and was once seen in multi-story industrial plants.

Controlling elevators

General controls

North American Elevator Buttons: A modern elevator has buttons to allow passengers to select the desired floor.

Asian Elevator Buttons: Car operating panel of a modern freight elevator.

A typical modern passenger elevator will have:
*Call buttons to choose a floor. Some of these may be key switches (to control access). In some elevators, certain floors are inaccessible unless one swipes a security card or enters a passcode (or both). In the United States and other countries, call button text & icons are raised to allow blind users to operate the elevator; many have Braille text besides.
Door open and door close buttons to instruct the elevator to close immediately or remain open longer. In some elevators, holding the door open for too long will trigger an audible alarm (This alarm might confuse some people to think that the elevator is overloaded).
*A stop switch (this is not allowed under British regulations) to halt the elevator (often used to hold an elevator open while freight is loaded). Keeping an elevator stopped for too long may trigger an alarm. Often, this will be a key switch.
*An alarm button or switch, which passengers can use to signal that they have been trapped in the elevator.

Some elevators may have one or more of the following:
*An elevator telephone, which can be used (in addition to the alarm) by a trapped passenger to call for help.
*A fireman's key switch, which places the elevator in a special operating mode designed to aid firefighters.
*A medical emergency key switch, which places the elevator in a special operating mode designed to aid medical personnel.
*Security controls: Elevators in modern buildings incorporate security features to control / prevent unauthorized floor access. One method is to use RFID card access in which call buttons don't register until an authorized card is detected. Another method is to require the passenger to enter a code, either on a separate keypad or the call buttons themselves, followed by the desired floor number.
*Hold button: Larger elevators used for freight and hospital beds have an appropriately named button that "holds" the door open longer.
*Cancel floor: On some elevator models, the building owner can enable a feature so that "double-clicking" a floor button will de-select it.

Other controls, which are generally inaccessible to the public (either because they are key switches, or because they are kept behind a locked panel, include:
*Switches to control the lights and ventilation fans in the elevator.
*An inspector's switch, which places the elevator in inspection mode (this may be situated on top of the elevator)
*An independent service switch, which selects whether the elevator's operation will be coordinated with other elevators in an elevator bank.
*Up and down buttons, to move the car up and down without selecting a specific floor. Some older elevators can only be operated this way.

Controls in early elevators

Manual pushbutton elevator controls.

*Some older freight elevators are controlled by switches operated by pulling on adjacent ropes. Safety interlocks ensure that the inner and outer doors are closed before the elevator is allowed to move.
*Early elevators had no automatic landing positioning. Elevators were operated by elevator operators using a motor controller. The controller was contained within a cylindrical container about the size and shape of a cake container and this was operated via a projecting handle. This allowed some control over the energy supplied to the motor (located at the top of the elevator shaft or beside the bottom of the elevator shaft) and so enabled the elevator to be accurately positioned — if the operator was sufficiently skilled. More typically the operator would have to "jog" the control to get the elevator reasonably close to the landing point and then direct the outgoing and incoming passengers to "watch the step". After stopping at the landing the operator would open the door/doors. Manually operated elevators were generally refitted or the cabs replaced by automatic equipment by the 1950s.
*Large buildings with multiple elevators of this type would also have an elevator dispatcher stationed in the lobby to direct passengers and to signal the operator to leave with the use of a mechanical "cricket" noisemaker.
*Some elevators still in operation have pushbutton manual controls.

Floor numbering

The elevator algorithm

The elevator algorithm, a simple algorithm by which a single elevator can decide where to stop, is summarized as follows:
*Continue travelling in the same direction while there are remaining requests in that same direction.
*If there are no further requests in that direction, then stop and become idle, or change direction if there are requests in the opposite direction.The elevator algorithm has found an application in computer operating systems as an algorithm for scheduling hard disk requests.Modern elevators use more complex heuristic algorithms to decide which request to service next.

Computer dispatched

Efficiencies of multiple elevators installed in an office building may increase if a central dispatcher is used to group passengers going to the same floor to the same elevator. In the industry, this is known as the 'Destination floor control system'. In buildings with these computer-dispatched elevator system, passengers key in their destination floor in a central dispatch panel located at the building lobby. The dispatch panel will then tell the passenger which elevator to use. Inside the elevator there is no call button to push (or the buttons are there but they cannot be pushed, they only indicate stopping floors). The system was first pioneered by Schindler Elevator as the Miconic 10. Manufacturers of such systems claim that average travelling time can be reduced by up to 30%. There are some problems with the system, though. Sometimes, one person enters the destination for a large group of people going to the same floor. The dispatching algorithm is usually unable to completely cater for the variation, and late comers may find the elevator they are assigned to is already full. Also, occasionally, one person may press the floor multiple times. This is common with up/down buttons when people believe this to hurry elevators. However, this will make the computer think multiple people are waiting and will allocate empty cars to serve this one person.

Special operating modes

Up peak

During Up Peak mode, elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one when they reach a pre-determined passenger load, or when they have had their doors opened for a certain period of time. The next elevator to be dispatched usually has its hall lantern or a "this car leaving next" sign illuminated to encourage passengers to make maximum use of the available elevator system capacity.

The commencement of Up Peak may be triggered by a time clock, by the departure of a certain number of fully loaded cars leaving the lobby within a given time period, or by a switch manually operated by a building attendant.

Down peak

During Down Peak mode, elevator cars in a group are sent away from the lobby towards the highest floor served, after which they commence running down the floors in response to hall calls placed by passengers wishing 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 may be triggered by a time clock, by the arrival of a certain number of fully loaded cars at the lobby within a given time period, or by a switch manually operated by a building attendant.

Sabbath service

In areas with large populations of observant Jews, one may find a "Sabbath elevator". In this mode, an elevator will stop automatically at every floor, allowing people to step on and off without having to press any buttons. Regenerative braking is also disabled if it is normally used, shunting energy collected from downward travel, and thus the gravitational potential energy of passengers, into a resistor network. This prevents violation of the Sabbath prohibition against doing useful work.[2]

Independent service

Independent service is a special service mode found on most elevators. It is activated by a key switch either inside the elevator itself or on a centralised control panel. When an elevator is placed on independent service, it will no longer respond to hall calls. (In a bank of elevators, traffic would be rerouted to the other elevators, while in a single elevator, the hall buttons will be disabled). The elevator will remain parked on a floor with its doors open until a floor is selected and the door close button is held until the elevator starts to travel. Independent service is useful when transporting large goods or moving groups of people between certain floors.

Inspect mode

Inspect mode is a mode that is activated only by a key switch that is usually located inside the elevator on the COP (control operating panel). When activated, the elevator will no longer respond to calls and comes immediately to a halt. In theory, this mode could be used as a way to stop the car in mid flight if one did not have a stop switch key. The elevator car will continue to remain idle until given a command from a corresponding access key switch. Key switches for access are usually located at the bottom floor and top floor. This enables the Elevator Mechanic to gain access to the pit of the elevator or the car top. The access key switch will bypass the door lock circuit for the floor it is located on and allow the car to move up at Inspection Speed. This speed can range from anywhere up to 60% of contract speed on most controllers. Since this key allows entry into the hoist way of the elevator, this key is not given out and is restricted only for use by qualified Elevator Mechanics.

Another type of inspect is called Car Top Inspection mode. Most modern elevators have test controls on the top the lift that will isolate the landing and car push stations (LOP and COP) there are three main control buttons fitted to the test control that consists of an UP button, DOWN button and RUN button, all work as dead man buttons i.e. no pressure on the buttons means no lift movement. The run button has to be activated along with a direction button. This test unit also has a Light, Alarm Button, Stop Button and usually some sort of door control switch. The speed that a lift on TEST can run at according to EN81-1/2 is 0.3m/s. Access is gained to the lift shaft by using a EURO type release key on most modern lifts, though many older lifts have a variety of access methods.

Fire service mode

Depending on the location of the elevator, fire service code will vary state to state and country to country. Fire service is usually split up into two modes. Phase One and Phase Two are separate modes that the elevator can go into.

Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the elevator has left the floor, depending on where the alarm was set off, the elevator will go to the Fire Recall Floor. However, if the alarm was activated on the fire recall floor, the elevator will have an alternate floor to recall to. When the elevator is recalled, it proceeds to the recall floor and stops with its doors open. The elevator will no longer respond to calls or move in direction. Located on the fire recall floor, is a fire service key switch. The fire service key switch has the ability to: turn fire service off, turn fire service on or to bypass fire service. The only way to return the elevator to normal service is to switch it to bypass after the alarms have reset.

Phase two mode can only be activated by a key switch located inside the elevator, on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase two key switch located on the COP, has three positions: off, on, and hold. By turning phase two on, you enable the car to move in direction. However, like independent service mode, the car will not respond to a car call unless you manually push and hold the door close button. Once the elevator gets to the desired floor, it will not open its doors unless you hold door open. This is in case the floor is burning and the firefighter can feel the heat and knows not to open the door. You must hold door open until the door is completely opened. For any reason the firefighter wishes to leave the elevator, they will use the hold position on the key switch to make sure the elevator remains at that floor. At anytime the firefighter wishes to return to the recall floor, they simply turn the key off and close the doors.

Standards

The mechanical, electrical and operational design of elevators are dictated according to various standards (aka elevator codes), which may typically be international, national, state, regional or city based. Where once many standards were prescriptive, specifying exact criteria which must be complied with, there has been a shift towards more performance-based standards where the onus falls on the designer to ensure that the elevator meets or exceeds the standard.

Some of the national elevator standards include:
*Australia - AS1735
*Canada - CAN/CSA B44
*Europe - EN 81 series (EN 81-1, EN 81-2, EN 81-28, EN 81-70, EN 12015, EN 12016, EN 13015, etc.)
*USA - ASME A17

Because an elevator is part of a building, it must also comply with standards relating to earthquake resilience, fire standards, electrical wiring rules and so forth.

Additional requirements relating to access by disabled persons, may be mandated by laws or regulations such as the Americans with Disabilities Act.

US and Canadian elevator standard specifics

Passenger elevators are required to conform to the American Society of Mechanical Engineer's Standard A17.1 Safety Code for Elevators and Escalators in most US and Canadian jurisdictions (In Canada the document is the CAN/CSA B44 Safety Standard which was harmonized with the US version in the 2000 edition.) In addition passenger elevators may be required to conform to the requirements of A17.3 for existing elevators where referenced by the local jurisdiction. Passenger elevators are tested using the ASME A17.2 Standard. The frequency of these tests is mandated by the local jurisdiction, which may be a town, city, or state standard.

Passenger elevators must also conform to many ancillary building codes including the Local or State building code, National Fire Protection Association standards for Electrical, Fire Sprinklers and Fire Alarms, Plumbing codes, and HVAC codes. In addition passenger elevators are required to conform to the American's with Disabilities Act and other State and Federal civil rights legislation regarding accessibility.

Residential elevators are required to conform to ASME A17.1. Platform and Wheelchair lifts are required to comply with ASME A18.1 in most US jurisdictions.

Most elevators have a location in which the permit for the building owner to operate the elevator is displayed. While some jurisdictions require the permit to be displayed in the elevator cab, other jurisdictions allow for the operating permit to be kept on file elsewhere - such as the maintenance office - and to be made available for inspection on demand. In such cases instead of the permit being displayed in the elevator cab, often a notice is posted in its place informing riders of where the actual permits are kept.

Notable Elevator Installations, by Location

Eiffel Tower

The Eiffel Tower has double-deck elevators built into the legs of the tower, serving the ground level to the first and second levels. Even though the shaft runs diagonally upwards with the contour of the tower, both the upper and lower cars remain horizontally level. The offset distance of the two cars changes throughout the journey.

There are four elevator cars of the traditional design that run from the second level to the third level. The cars are connected to their opposite pairs (opposite in the elevator landing/hall) and use each other as the counterweight. As one car ascends from level 2, the other descends from level 3. The operations of these elevators are synchronized by a light signal in the car.

Taipei 101

It is worth noting that Taipei 101 uses double-deck elevators to service the main building tenants, although it is not the first of such implementations. Within the building are several sky lobbies accessible via non-stop service elevators; after which the tenants must transfer elevators to reach their floor. Each sky lobby is also equipped with the "floor dispatch" system as described above.

The observation deck elevators are the fastest in the world. They accelerate to a top speed of 1010 meters per minute in 16 seconds -- after which it begins to slow down for the arrival to the observation deck. The upward journey from 5th floor to 89th floor is 352 meters long, and is completed in a matter of 37 seconds. The downward journey is completed at a reduced speed throughout.

The car and its counterweight are shaped like a bullet-train to minimize travelling noise. The cabin features a pair of interactive displays showing the car's vertical position in the tower, along with floor, altitude, timer, and vertical speed. Further, the cabin is pressurized to enhance passenger comfort in adapting to rapid changes in air pressure.

The Gateway Arch

The interior of one of the Gateway Arch tramway cars

The Gateway Arch in St. Louis, Missouri has a unique elevator system which carries passengers from the visitors center underneath the Arch to the observation deck at the top of the structure.

Called a tram or tramway, people enter this unique tramway much as one would enter an ordinary elevator, through double doors. Passing through the doors the passengers in small groups enter a horizontal cylindrical compartment containing seats on each side and a flat floor. A number of these compartments are linked to form a train. These compartments each individually retain an appropriate level orientation by tilting while the entire train follows curved tracks up one leg of the arch.

There are two tramways within the Arch, one at the north end, and the other at the south end. The entry doors have windows, so people traveling within the Arch are able to see the interior structure of the Arch during the ride to and from the observation deck.

View up the shaft of the elevator at the new city hall, Hannover, Germany.

New city hall, Hanover, Germany

Sketch of the elevator at the new city hall, Hannover, Germany, showing the cabin both at the bottom and the top

The elevator in the new city hall in Hanover, Germany is a technical rarity, and unique in Europe, as the elevator starts straight up but then changes its angle by 15 degrees to follow the contour of the dome of the hall. The cabin therefore tilts 15 degrees during the ride. The elevator travels a height of 43 meters. The new city hall was built in 1913. The elevator was destroyed in 1943 and rebuilt in 1954.

Luxor Inclinator Elevator

In Las Vegas, Nevada, at the Luxor Casino, is the Inclinator. The shape of this casino is a pyramid. Therefore, the elevator travels up the side of the pyramid at a 39 degree angle.

Twilight Zone Tower of Terror

Main Article: Twilight Zone Tower of Terror

The Twilight Zone Tower of Terror is the common name for a series of a free-fall elevator attractions at the Disney-MGM Studios park in Orlando, Disney's California Adventure park in Anaheim, the Walt Disney Studios Park in Paris and the Tokyo DisneySea park in Tokyo. The central element of this attraction is the unique free-fall experience achieved through the use of a state-of-the-art elevator system. For safety reasons, passengers are seated and secured in their seats rather than allowing them to stand. Unlike most traction elevators, the elevator car and counterweight are joined using a cable system in a continuous loop running through both the top and the bottom of the drop shaft. This allows the drive motor to pull down on the elevator car from underneath, a feature which is used to raise passengers out of their seats early in the drop sequence by applying downward acceleration in addition to that of gravity. Furthermore, the uniquely fast and powerful drive motor allows the elevator to ascend to the top in mere seconds.

Finally, the passenger cab is mechanically removed from the main elevator car so that the elevator shaft can efficiently be used continuously while the passenger cabs can alternatingly be removed to permit passenger boarding. The Disney-MGM Studios version of the attraction achieves this operation in a very different fashion than that of the other versions, although the end effect is similar. All of the attraction buildings feature multiple elevator shafts to further improve throughput. The doorways of the top few "floors" are open to the outdoor environment, offering a dramatic view for both the ride passengers and the street-level observers.

"Top of the Rock" elevators

Guests ascending to the 67th, 69th, and 70th level observation decks (dubbed "Top of the Rock") atop the GE Building at Rockefeller Center in New York City ride a high-speed glass-top elevator. When entering the cab, it appears to be any normal elevator ride. However, once the cab begins moving, the interior lights turn off and a special blue light above the cab turns on. This lights the entire shaft, so riders can see the moving cab through its glass ceiling as it rises and lowers through the shaft. Music plays and various animations are also displayed on the ceiling. The entire ride takes about 60 seconds.

Apple Store, New York City

Otis has recently installed an elevator that takes Apple customers from the 32 foot ground floor cube to the basement store. The elevator, except for the floor, is made completely of glass. On May 29, 2006, just a week after its opening, it has already made the news after trapping five passengers after the inner door repeatedly opened and closed. [3]

Elevators for urban transport

In some towns, where terrain is difficult enough to justify, elevators are used as part of the urban transport systems.

Examples

* Bad Schandau Elevator in Bad Schandau, Germany
* Hammetschwand Elevator in Bürgenstock, Switzerland

Elevator accidents

Maintenance is crucial for the safety of an elevator since they usually operate more than 20-30 years before replacement or modernization. Although elevators are the safest means of transport in the world, accidents do sometimes happen.

Hong Kong

*Tin Shui Wai, March 2006 - 3 housewives and 2 of their children living in a public housing estate (Tin Tsak Estate) in Tin Shui Wai, Hong Kong, were taking one of the building's 6 Schindler elevators up from the ground floor. As the elevator rose past the 29/F, the elevator suddenly moved up and down through the span of the shaft (between G/F and 40/F). The elevator was reported to have jerked up and down several stories 3 times and shook violently laterally. Reports said the passengers were scared to death and shrieked, drawing similarities to an amusement park ride where one is strapped to seats and is repeatedly brought up and down. The passengers had claimed that no one answered the Alarm button intercom. It just so happened that Ms Au, a woman waiting for an elevator in the lobby, saw the hall position indicator flash nonsense - one moment it showed "40/F" and just seconds later it would show "30/F". She was worried that someone would be stuck inside and alerted the building management. The elevator doors suddenly opened and the passengers fled the elevator. The elevators, as with all government Housing Authority elevators in public estates, are maintained by their original manufacturer (in this case, Schindler). The elevator was inspected and the only explanation given was one from a mechanic who said that "it was normal for an elevator to grind to a halt if it detects an abnormality, and then carry out its learning mode where it detects and 'learns' its position by travelling to the top and bottom of the shaft".
*Fanling, January 2002 - 11 year old boy killed involving Schindler elevator. Elevator ascended with the doors still open. Hong Kong Electrical Mechanical Services Department (EMSD) attributed problem to lack of an ascending protection device, and has since ordered the Fanling complex to install these devices. Schindler has never publicly admitted responsibility for this incident and blamed an OTIS subsidiary for its poor maintenance [4]. (Chinese newspaper documents the Japanese incident and relates it to the 2002 Hong Kong incident - pictures on the left are the 'deadly elevators' in Hong Kong)

Japan

*Minato-ku, Tokyo, Japan, July 12 2006 - The Schindler Elevator installed right next to the one in Minato Ward that killed 16 year old Ichikawa Hirosuke trapped a woman and a Schindler engineer riding along for 30 minutes. Once again the building elevators have been taken out of service. While no one was hurt, this story notes that Schindler has taken over the maintenance of the elevators at this building. Source: [5]
*Chiba Prefecture, Japan, June 2006 -Similar to Minato Ward incident although with no fatalities also involving Schindler elevator. Incident first occurs on June 1, 2 days before the Minato incident. Investigation reveals no irregularities but same type of accident takes place days later on June 10th. [6]. Plates with Schindler's name and contact number were shown in lobby of these elevators on Japanese TV.
*Minato-ku, Tokyo, Japan, June 2006 - a 16-year old high school student was killed as he was backing out of an elevator with his bicycle when the elevator suddenly rose with the doors still open, crushing his skull.
* Hokkaido, Tokyo, September 20 - a 52 year-old man working for a "fire prevention center" fell down the shaft to his death. Using a special key, the victim opened the 1-floor landing door while the elevator was not in the first floor. This case involved a Hitachi Elevator installed in 1974 and maintained by Hitachi. Information source: Hokkaido Shinbunsha September 21, 2004 (morning edition).
*Meguro, Tokyo, Japan, September 15, 2004 - the victim (no detail about his identity) fell down the shaft to his death. This case involved a Toshiba Elevator installed in 1993. Maintenance company is not mentioned. Source: Japanese Elevator Association.

Canada

*Toronto - five people receive broken ankles and other minor injuries, as an Otis parking garage hydraulic elevator in a National Life building on University Avenue plummets five floors. [7] [8] [9]

U.S.

*New York 2004. Fatality involving malfunction of Schindler freight elevator. [10] [11]
*Texas, August 16, 2003. Decapitation of doctor in old Otis made elevator. O'Hare, P. (2003, August. 17). Doctor decapitated by faulty elevator at St. Joseph Hospital. Houson Chronicle. Retrieved on June 20, 2006. Internal investigation concluded that a wire in an electrical panel was incorrectly connected. Kone, Inc., which had recently been servicing the elevator was later dismissed. [12]
*New Orleans, July 2003. Fatality involving malfunction of elevator at the Kenner Regional Medical Center. [13]
*Michigan 1999. Woman age 56 on gurney became lodged between elevator car and shaft wall and dragged four floors. [14]
*The Bronx, New York, January 6, 1995. Runaway elevator in office building decapitated 55-year-old James Chenault as he tried to help fellow passengers out of a malfunctioning car. [15]

Mexico

*Cancun, June 2006. A teenager vacationing with his family at the hotel Royal Solaris in Cancun fell to his death in an elevator shaft. The shaft was completely empty. Mitsubishi was about to do a modernization job in this shaft.

England

*London, June 2006. A 47-year-old man was killed when he plummeted eight floors during a refurbishment job in an office High Holborn, London. The lift was being modernized by a company called Guidelines. (Source: Construction News)

Russia

*Omsk, June 2006. An eight-month-old baby died when an elevator in an apartment building fell six stories. The elevator in question was not installed by a major elevator manufacturer. (Source: Nowosti)

Manufacturers of elevators

*American Elevator Co
*AMTECH Elevator Services (company acquired by Otis)
*Butlersbuddy Inc.
* Beacon Elevator Co. (p) Ltd.
* Daldoss (Italian - limited presence in Hong Kong)
* Delta Elevator (Canadian - mostly Ontario)
* Dongyang - once one of the two largest Korean independent elevator/escalator makers (with LG Goldstar). Dongyang was acquired by Thyssenkrupp to become Dongyang ThyssenKrupp.
* ELEX
* Enor (Spain)
*Express Lifts Northampton (company acquired by Otis)
* FIAM Lifts (Italian maker of older elevators - company acquired by KONE)
*Fujitec
* GEC Elevator (acquired by OTIS) - many contracts in Hong Kong (especially buildings from the British Government)
* Golden Friends Corporation - (Taiwan)
* Hitachi Elevator
* Inclinator Company of America (Premere Residential Elevators)
*KLEEMANN Complete Lifts - Greek Elevator Company
*KONE (acquired Montgomery Elevator/Escalators)
* Koppel A.W. (Italy)
* LG Goldstar - Korean company now "Sigma" and acquired by OTIS to form LG OTIS.
* Long Elevator Co. Serving Illinios, Indiana and Missouri
*Mitsubishi Electric Elevator/Escalator Division (maintained by its Ryoden subsidiary in some locales)
*Motion Control Engineering - Major Independent, Elevator Control Systems Manufacturer
*North American Elevator Services
*ORONA S.Coop.
*Otis (World's largest elevator company, acquired Esco Hydraulic Elevators)
* Richmond Elevator (Richmond, BC, Canada maker of mostly Hydraulic elevators)
* Sabiem Lifts (Italian maker - now part of the Kone group - presence in older Hong Kong buildings)
* Schumacher Elevator (seen in Toronto, ON)
*Schindler Group (2nd largest elevator/escalator manufacturer; acquired Westinghouse Elevators/Escalators; control pannel irregularities being investigated as of June 2006 in Japan)
*The Elevator Contractors of America
*ThyssenKrupp Elevator (acquired Dover Elevator and US Elevator - largest elevator manufacturer in the Americas and third largest world-wide.)
*Toshiba Elevator and Building Systems Corporation

Elevator: Encyclopedia BETA

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