The modern elevator industry launched with a PR stunt.
At the 1853-’54 New York World's Fair, Elisha Otis rose above the audience in the Crystal Palace, standing on a platform lifted by a rope within an open-sided shaft.
Halfway up, he ordered an axeman to cut the rope. He dropped mere inches before his locking safety brake halted the platform from falling.
Orders for Otis passenger elevators took off immediately.
Related Story: Shafted
These “safety elevators” enabled cities to rise skyward.
Today most buildings of more than a few stories use traction elevators not unlike their late 19th-century counterparts: Traction elevators have a cab and a counterweight attached to woven steel cables, raised and lowered by a motorized sheave at the top of the shaft and halted by a system of brakes.
Guide rails installed vertically in the shaft direct the course of travel. An emergency exit that opens from the exterior of the cab’s roof is used only by rescue personnel.
The innovations Otis introduced in the mid-19th century have not changed substantially in the past century. Electricity replaced steam power, woven steel cables replaced hemp ropes and lighter carbon-fiber ropes (such as KONE’s UltraRope) are beginning to replace steel.
Where control systems were once manually operated by an elevator attendant, artificial intelligence now drives a new breed of so-called “smart elevators." These have been installed in large cities like New York, which decrease ride times by learning traffic patterns and grouping passengers together based on common destination floors.
Vertical-transportation innovations are showing up in megacities such as Dubai, where Otis double-deck lifts speed as quickly as 20 miles per hour up and down the Burj Khalifa, the world’s tallest structure.
In Oregon emerging technology may redefine how elevators move passengers. After years of testing, Thyssenkrupp has recently unveiled magnetic-levitation-powered elevators that forego cables entirely, meaning they can zip up, down, sideways and diagonally — a Willy Wonka-like invention nearly as dramatic as Otis’ legendary rope-cutting feat.
This post is a companion piece to Shafted, our in-depth feature about elevator malfunction.