Give Us the Power...
The power elevator
debuted mid-19th century in the U.S. as a simple freight hoist operating
between just two floors in a New York City building. By 1853, Elisha
Graves Otis was at the New York Crystal Palace exposition, demonstrating
an elevator with a "safety" to break the cab's fall in
case of rope failure, a defining moment in elevator development.
By 1857, the country's first Otis passenger elevator was in operation
at a New York City department store, and, ten years later, Elisha's
sons went on to found Otis Brothers and Company in Yonkers, NY,
eventually to achieve mass production of elevators in the thousands.
Various other elevator designs appeared on the landscape, including
screw-driven and rope-geared, hydraulic models.
An Electric Moment...
Later in the
1800s, with the advent of electricity, the electric motor was integrated
into elevator technology by German inventor Werner von Siemens.
With the motor mounted at the bottom of the cab, this design employed
a gearing scheme to climb shaft walls fitted with racks. In 1887,
an electric elevator was developed in Baltimore, using a revolving
drum to wind the hoisting rope, but these drums could not practically
be made large enough to store the long hoisting ropes that would
be required by skyscrapers.
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