Archive for April, 2012
A Brief Look at the History of the Modern Elevator
Today, most people do not think twice about using an elevator and there are a number of uses for these devices, including not just the traditional office building elevator, but also commercial elevators. Sometimes called just a “lift” in parts of Europe and elsewhere, elevators provide a mechanism for moving people, as well as items, up and down in a building.
The first depiction of an elevator occurs in the Roman times, with some suggesting that Archimedes constructed a basic elevator around 200BC. Lifts have also been traced back to the ancient Egyptian times, as well as the medieval period, where lifts were often used to move goods around the castle. While these early prototypes were typically rope driven elevators, with a rope and pulley system used to move a small car, sometimes powered by cows or other large work animals, a few early hydraulic elevators were developed as well during the eighteen-hundreds, although these were not very efficient.
As is the case with many types of inventions, one of the biggest innovations was aimed at improving safety. This was the invention of the safety elevator, which was first demonstrated in the middle of the eighteen-hundreds by Elisha Otis, who is often considered the father of the elevator. The elevator was designed so that if the elevator should accelerate at an unnatural rate, such as if a cable or rope broke, a special stopping unit would engage, preventing the elevator from falling completely.
Up until this time, passenger elevators were not as common in businesses, in part because of safety concerns, but also technical limitations. Shorty after Otis’s live demonstration of his new and improved elevator safety system, he went on to install his first commercial hydraulic elevator in the brand new E.V. Haughwout Building in New York. Otis went on to have a very successful career building elevators and today the Otis Elevator brand is still well known and, for many in the industry, is synonymous with the passenger elevator.
There are a number of different types of elevators, but they generally fall into two basic categories, mechanical and hydraulic. The first hydraulic elevators, which were developed around the same time Otis was building his safety elevator. However, these generally relied upon a very deep hole located under the elevator shaft. The hole was required to be as deep as the elevator needed to go up, as a result making them impractical for widespread use. Instead the mechanical cable driven elevator, which often used a counter balance system to move the elevator car, would remain popular for some time. By the nineteen-seventies, however, a more efficient hydraulic elevator would be developed and today hydraulic passenger elevators are quite common in shorter buildings.
The path to a safe and efficient elevator is one that did not happen overnight, but thanks to the inventions of Elisha Otis and other pioneers in the development of the passenger elevator, they are very safe and reliable today. Elevators provide not just a quick way of moving between floors, but also a means for those who use wheelchairs or other mobility vehicles to move between floors.
Comments are off for this postThe Development of a Safe Passenger Elevator
While dumbwaiters, which are a special type of lifting aid, have been used in construction for thousands of years, dating back the times of the early Egyptians, these devices were very rarely used to transport people.
This was in large part due to the dangers associated with early dumbwaiters, which were often only suspended by a rope, which was prone to breaking. As a result, most people were very wary of elevators, so they were seldom used. In big cities, buildings were usually at most five stories high, because this was about as high as most people could climb on the stairs without becoming tired.
Even in early times, the problem with building a passenger elevator was not the lifting mechanism itself, because there were plenty of hoists developed capable of lifting a large amount of weigh. With pascals discoveries 1600’s, there were also several hydraulic lifting systems available, as well as steam powered engines, so lifting was not the problem. Instead, safety was the major barrier preventing the acceptance of the passenger elevator.
The issue of safety was finally addressed by Elisha Graves Otis, who is today known as the father of the passenger elevator. Otis, who was an inventor at heart, was working for a manufacturing company and overseeing the construction of one of their new plants.
After several accidents with their dumbwaiter, which was used to move construction supplies, Otis developed a safety system, which engaged if the dumbwaiter rope broke. The safety system consisted of a spring loaded spike system, which would stick into the sides of the dumbwaiter shaft, stopping the dumbwaiter car, if there was a rope failure.
Once the construction of the new manufacturing plant was complete, Otis was set to move on to California in hopes of finding gold, but before he could leave, he was approached by several builders who were interested in his dumbwaiter brake system. So, instead of leaving New York, Otis stayed and began manufacturing lifts with his built in brake system.
By 1854, Otis had developed his own passenger elevator, which took advantage of the braking system. At the Crystal Palace, he raised the elevator up in the elevator and cut the rope, showcasing the safety of his elevator. Otis would quickly become inundated with request for his elevator, with the first passenger elevator installed in 1857. With this, the Otis Elevator Company was born, which today is one of the most recognized names in the elevator industry.
With the adoption of the passenger elevator, buildings could be built much larger and skyscrapers would soon emerge, with the sky quite literally being the limit. Many elevators would make use of steam power and also hydraulic power.
In 1889, the first electric passenger elevator was installed, which took advantage of Thomas Edison’s central electric system that was installed in New York. By 1894, there were attendentless passenger elevators, which could be operated by the elevator users and less than 100 years after the first Otis elevator, a dispatching system capable of operating a bank of two elevators at once was developed.
Today, the passenger elevator is more popular than ever. It can be found in most large buildings, greatly improving accessibility for the mobility challenged. The passenger elevator is also becoming increasingly popular in residential settings, with several single or double user residential elevator kits available.
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