Elevator

Elevator

An elevator (or lift) is a type of vertical transportation device that moves people or goods between floors of a building, vessel, or other structure. Elevators are typically powered by electric motors that drive traction cables and counterweight systems like a hoist, although some are powered by hydraulic fluid-driven piston systems.

Elevator in the Spalding Building, Portland, Oregon

History

The concept of the elevator dates back to ancient times. The Roman architect Vitruvius reported that Archimedes built his first elevator, probably in 236 BC. In medieval times, elevators were powered by human or animal labor.

Medieval depiction of an elevator

The first reference to an elevator is in the works of the Roman architect Vitruvius, who reported that Archimedes (c. 287 BC – c. 212 BC) built his first elevator probably in 236 BC. In some literary sources, elevators were mentioned as cabs on a hemp rope powered by hand or by animals.

In 1852, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. Otis demonstrated his safety system at the New York World's Fair in 1854, and the first passenger elevator was installed in the Haughwout Building in New York City in 1857.

Elisha Otis demonstrating his safety elevator in 1854

Types of Elevators

Traction Elevators

Traction elevators are the most common type of elevator. They are lifted by ropes, which pass over a wheel attached to an electric motor above the elevator shaft. The weight of the elevator car is balanced by a counterweight.

Hydraulic Elevators

Hydraulic elevators are supported by a piston at the bottom of the elevator that pushes the elevator up. They are used for low-rise buildings of 2-8 floors and have a slower speed compared to traction elevators.

Interior of a Schindler 330A hydraulic elevator

Machine-Room-Less (MRL) Elevators

Machine-room-less elevators are a type of traction elevator that do not require a separate machine room. The machinery is located in the hoistway itself.

Modern Developments

Modern elevators are equipped with a variety of safety features, including emergency stop buttons, interlocks, and communication systems. They are also designed to be energy efficient and environmentally friendly.

Modern elevator in the Berlin U-Bahn

Related Pages

• Escalator
• Moving walkway
• Dumbwaiter
• Elevator music