What Is an Escalator?
Escalators are an efficient and safe way to transport people vertically from one floor to another. They are popular in many commercial and residential buildings.
The global escalator chain market is segmented into types (step chains and drive chains), applications, and regions. North America, Europe, Asia Pacific, and the Middle East & Africa are major markets for escalator chains.
Staircase Configuration
Escalators typically have stationary (nonmoving) top and bottom landing platforms, a metal truss that connects the two platforms, and two pairs of tracks on which a collapsible staircase is pulled by a continuous chain that loops around two pairs of gears. The escalator also has moving handrails that are coordinated to move at the same speed as the steps.
The truss is connected to each of the landing platforms by steel or concrete supports that carry straight track sections. At each end, the truss supports a floor plate and a comb plate that are flush with the surface of the floor. The comb plate is shaped like a comb and has grooves that mesh with the grooves on each step’s edge.
When the truss is lifted into position, it is anchored to the support wall at the upper landing and to the lower landing platform by steel flanges. The escalator is then jockeyed into place between the landing holes. There are a number of methods for doing so, including a scissors lift apparatus mounted on a wheeled support platform and outfitted with a locator assembly to aid in vertical and angular alignment.
Once the truss is in place, it’s time to start installing the steps. Each stair has its own set of wheels, which are the front and back wheels on separate tracks running down each side of the truss.
These wheels are attached to a drive gear at the top landing platform. The escalator’s motor then rotates the chains that form the truss and pulls the wheels along the track.
The truss then supports a handrail on each side of the escalator. The handrail is a moving belt that is connected to the chain by a series of pulleys. Its movements are synchronized with those of the steps, and it serves as a guide for passengers.
When the escalator is in use, it’s possible for one or more of the handrails to become trapped by a piece of debris that has been caught on a handrail inlet switch. When the inlet switches detect an obstruction, they trigger a motor to shut down the escalator.
Steps Connected in Series
An escalator consists of an endlessly circulating chain of steps that transports people between floors. Escalators are designed to move large numbers of passengers with minimal waiting intervals and can often handle up to 450 people per five-minute period.
Each step on an escalator has two sets of wheels. One set of wheels, called the front wheels, pulls the step along its track as it escalator chain moves from the bottom platform to the top, while the other set of wheels, called the trailer wheels, simply “trail” behind the front wheels.
The front and back wheels are connected to each other by a continuous metal chain that forms a closed loop. This configuration allows the steps to bend in relation to each other and enables them to create a staircase as they are pulled from the bottom platform and then pushed back up to the top.
In most escalators the steps are solid, one-piece die-cast aluminum (aluminum shaped in a mold using pressure). Rubber mats may be affixed to the surface of each step to reduce slippage and yellow demarcation lines are sometimes added to clearly indicate their edges.
Cleated treads and risers are also common on escalators. These cleated surfaces are typically made of steel or aluminum and have comb-like protrusions that mesh with the comb plates on the top and bottom landing platforms and the succeeding steps in the chain.
To prevent the steps from slipping, rubber mats are usually affixed to the surface of each one. Some models feature a ribbed appearance on the risers and treads. These models are popular in areas where abrasion and damage is a concern.
Escalator chains are typically connected to the drive gear with a series of pulleys that keep the steps moving at the same speed as the main drive. The handrails on each side of the steps are also connected to the chain with a series of pulleys.
Escalators are built with various design factors in mind, including physical requirements, location, traffic patterns, safety considerations and aesthetics. These factors must be considered before building an escalator, as they will determine its length and pitch and how upward and downward traffic is separated and load/unload areas are established.
Staircase Curves
Staircase curves are often eye-catching and add an extra dimension escalator chain of design to buildings. They are most common in shopping centres, offices and public buildings where they can make a statement while offering safe access to floors.
Curved escalators are a unique feature in many airports, malls and department stores. They are not as common in residential buildings and can be more expensive to install.
A curved escalator has two parallel tracks, with wheels on each track moving up and down in opposite directions for safety reasons. Each set of wheels is attached to a guide rail at the end to ensure that they remain aligned.
The outer edges of the steps are also curved, which allows passengers to stand safely on both sides of the escalator. The handrails on the sides move at the same speed as the steps, and are attached to the escalator chain at each end by pulleys.
In Home Designer Pro, it is possible to curve a staircase by holding down the Alt/Option key while dragging the top/bottom edit handle on the stairs. This activates the Alternate edit behavior temporarily, which will allow you to curve the stairs without losing any changes you have made to the stair.
You can also curve a single stair segment by highlighting the segment and clicking on the top/bottom edit handles. Alternatively, you can drag the top/bottom edit handles while pressing on a stair segment in order to change its orientation.
Unlike straight stairs, curved staircases require careful planning to ensure that the stair is in the correct direction and does not impede the flow of traffic in the building. In addition, a stair that is curved must be built to the appropriate height and slope to minimize falls during use.
When designing a curved stair, it is important to consider the following factors:
Steps demarcation lines: In order to clearly delineate the edge of each individual step, manufacturers offer these stairs trimmed in yellow.
The stair is also equipped with a guard that minimises falls from elevated walking surfaces and the side of the stairway.
Staircase Transitions
The transitions from the stair band to a landing area in an escalator are connected in series. Depending on the type of escalator, the steps are connected to a drive chain that circulates along one or more main and additional guides.
Each step consists of a walking surface, a front side and a back end opposite to the walking surface. In a curved escalator, these lateral sides are disposed on helically arranged tracks that are guided by step roller guides. The step rollers are also guided on a guide couple of rear bearings that is arranged at a lower level than the guide couple of front bearings, so that the step is inclined slightly backwards. This inclination is useful for reducing the space needed for the transition zone and it allows the step to be geared.
A fanned out escalator is constructed with a set of steps that have a central step. The broader steps of the stair band are positioned on the upper left and right side. These broader steps can accommodate, for example, a pushchair or a wheelchair on their widened platform, if desired.
For this purpose, a drive chain with links is present, wherein the links include arms that are attached to the shafts of the front bearings of both movable and non-movable steps. Likewise, the holding oscillating arms of the movable steps are coupled by their ends to the shafts of the front bearings on the non-movable steps.
This enables the central step to be detached in the reversing region without detaching the rest of the stair band, and it does not require a significant expenditure of effort, since the distance between the rear sides of the steps is small enough that maintenance personnel can gain access with both hands and remove the step from the step axle.
Another solution is to install lateral flange elements that form part of a bottom panel that moves with the steps during operation of the escalator. In one particularly preferred embodiment, these lateral flange elements are connected to the steps and are arranged on the rotational axis of the step in such a way that they are situated on an opposite plane to the walking surface.
