Introduction:
Whether at the mall or at the airport, escalators are used on a regular basis. They are often taken for granted, but are actually the most expensive and biggest machines used by people regularly. Based on the inclined belt, the escalator is actually a very simple device. Stairs are pulled by rotating chain loops, making a very effective way for transporting a lot of people over a short distance. A specialized form of the escalator is moving ramps or sidewalks (travelators). These travelators move people and materials horizontally.
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