Buildings keep rising…so we rise to the challenge. As building technology changes and progresses, our elevator technology does the same. Otis has a long history of meeting new challenges with ongoing innovation. While there is a wide range of elevators to fit every need, they fall under three basic types: gearless traction, geared traction and machine-roomless.

Machine-Roomless Elevators

This revolutionary elevator system is based on the first major breakthrough in lifting technology in nearly 100 years. Designed for buildings between two and 30 stories, this system employs a smaller sheave than conventional geared and gearless elevators. The reduced sheave size, together with a redesigned machine, allows the machine to be mounted within the hoistway itself—eliminating the need for a bulky machine room on the roof.

Just as unique are the flat polyurethane-coated steel belts, an Otis invention for the Gen2™ elevator system, that replace the heavy, woven steel cables that have been the industry standard since the 1800s. The belts make the smaller sheave possible. They are only 0.1 inch (3 mm) thick, yet they are as strong as woven steel cables and far more durable, flexible and space-saving.

Machine-roomless elevators are ideal for a variety of applications—and the most unusual, such as the Christ the Redeemer monument in Rio de Janeiro.

Gearless Traction Elevators

In 1903, Otis introduced the design that would become the standard in the elevator industry—the gearless traction elevator. These elevators typically operate at speeds greater than 500 feet per minute (2.54 meters per second).
In a gearless traction machine, woven steel cables called hoisting ropes are attached to the top of the elevator car and wrapped around the drive sheave in special grooves. The other ends of the cables are attached to a counterweight that moves up and down in the hoistway on its own guiderails. The combined weight of the elevator car and the counterweight presses the cables into the drive sheave grooves, providing the necessary traction as the sheave turns. Gearless technology makes the tallest buildings in the world possible, such as Malaysia’s Petronas Towers. See more.
 

Geared Traction Elevators

As the name implies, the electric motor in this design drives a gear-type reduction unit, which turns the hoisting sheave. While slower than a typical gearless elevator, the gear reduction offers the advantage of requiring a less powerful motor to turn the sheave. These elevators typically operate at speeds from 350 to 500 feet per minute (1.7 to 2.5 meters per second) and carry loads of up to 30,000 pounds (13,600 kgs). An electrically controlled brake between the motor and the reduction unit stops the elevator, holding the car at the desired floor level.