bf elevator co -iranian elevator company

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, Elisa 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,

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.

Motor technology and control methods evolved rapidly. In 1889 came the direct-connected geared electric

elevator, allowing for the building of significantly taller structures. By 1903, this design had evolved into the

gearless traction electric elevator, allowing hundred-plus story buildings to become possible and forever

changing the urban landscape. Multi-speed motors replaced the original single-speed models to help with

landing-leveling and smoother overall operation. Electromagnet technology replaced manual rope-driven

switching and braking. Push-button controls and various complex signal systems modernized the elevator

even further. Safety improvements have been continual, including a notable development by Charles Otis,

son of original "safety" inventor Elisa, that engaged the "safety" at any excessive speed, even if the hoisting

rope remained intact.

As Good As It Gets

Today, there are intricate governors and switching schemes to carefully control cab speeds in any situation.

"Buttons" have been giving way to keypads. Virtually all commercial elevators operate automatically and the

computer age has brought the microchip-based capability to operate vast banks of elevators with precise

scheduling, maximized efficiency and extreme safety. Elevators have become a medium of architectural

expression as compelling as the buildings in which they're installed, and new technologies and designs

regularly allow the human spirit to soar!

BF Elevator co

Tel : (9821) 879-0101 Fax : (9821) 879-3203