Elevator Research&Technologies 3.65

It is interesting to note that the word `lift’ appears to derive from Scandinavia possibly from the word `liften’ around the Middle Ages (476 A.D.-1500 A.D.) whereas elevator derives from the Latin word `elevare’- to lift up. The words `lift’ and `elevator’ used to describe an apparatus to satisfy the vertical transportation needs of persons or materials, possibly evolved around the 1850′s.

The modern-day lift has come a far way and represents a very complex piece of equipment which forms an integral part of any high rise building.

Elevators are simple means of lifting material and have been in existence in some form or the other for ages. The ancient Greeks and Romans had hoists to lift stones and building material powered by horses and slaves. The medieval kings and emperors in Asia and Europe built up cathedrals, forts and mansions on rough hills and used hoist technique to lift building material.

With the advent of industrial era in the middle of the 19th century similar kind of hoists used to be employed for lifting material. But this method was very crude and unsafe and posed a regular threat; if the hoist rope snapped the whole thing would come hurtling down

A young supervisor of a small New York firm Elisha Otis soon found a way out. He devised a system of springs and ratchets that prevented the lifted material from falling down when the hoist ropes broke. Barely did he realize then that the system he invented was the world’s first `safety mechanism’ for elevating material To him, the only thing which mattered was that he had been able to solve his factory’s problem.

This is how the first elevator of the world was born in 1853 in the form of a freight elevating system. Elisha Otis named is as “safe elevator”. The invention did attract a little attention from his friends and admirers who persuaded him to set up a small shed near the Hudson River in a New York suburb.

So, the first elevator manufacturing company, started business in a small dingy shed on September 20, 1853. No one really cared much about this small, dingy shed what was produced in there. But a determined Elisha wouldn’t rest at that. He decided to organize an exhibition of his `safe elevator’ at the Crystal Palace in New York in May 1854. It was a spectacular show . With the complete safe elevator installed in the main area of the exhibition hall, Otis had the hoist platform-with boxes, barrels and freight-and himself on it-pulled up to a height for all to see. Then he ordered the rope cut.

It was breathtaking. The audience watched in bewildering silence- a support-less platform remaining static. As the tension on the wagon safety mechanism was released, it straightened out to engage the thatchet bars securely holding the hoist platform motionless. A beaming Elisha Otis bowed with his hat in one hand and assured the stunned onlookers: “All safe gentlemen, all safe”.

Close on the heels of his success with freight elevators, Elisha Otis built the first passenger elevator and installed it in a New York department store.

For the first quarter century’s since 1853, when Elisha Graves Otis started the business of manufacturing safety elevators, steam engines provided the motive power for elevators. In 1878 the first hydraulic elevators, using water pressure, were installed and 11 years later, the earliest electric elevators. Gearless traction electric elevators, capable of the high speeds required in even today’s tallest skyscraper, appeared in 1903.

Automatic elevators with simple control systems, for slow speed service in private residences, became available as early as 1894. More advanced control systems were introduced in 1924 while 25 years later, in 1949, the first fully automatic elevators were installed to handle traffic in tall, busy buildings.

Also in the 1940s, Americans by the millions began moving to the suburbs, demanding dependable elevator service even in garden apartments and office buildings of only two or three stories. The need was answered by the modern, oil-driven hydraulic elevator, using electrically-powered rotary pumps under completely automatic control.

By the 1960s elevators were increasingly standardized and efficient assembly-line methods were being used to hold down costs and to speed installation to help complete buildings sooner.

At first passengers were at the mercy of the elevator operator. He could stop for you or, if he did not feel like it, he could pass you up. Moreover, at a speed of 180 metres per minute, it was impossible for even the best intentioned operators to read floor numbers, pay attention to signals and deal with impatient passengers. Both problems were solved by automatic levelling devices and signal controls. This made possible speeds of 420 meters per minute and permitted big buildings to be served by a smaller number of elevators.

With the growing urbanization all over the world the demand of elevators has gone up considerably. The software as well as the hardware has been dramatically modernized over last two decades. The introduction of solid state electronics in the field elevators brought about a high degree of precision and riding quality.

In the late `70′s, micro processor controlled elevators were introduced which gave tremendous decision making powers to elevator system. Revolutionary in concept and design using the latest chip technology to provide the most economical operation, the new elevonic micro-computer elevator systems have vastly improved passenger travel time resulting in substantial savings of energy. The elevonic system is software based and instructions are programmed and fed into the elevator on the basis of which it works. Since it is software based it can be easily reprogrammed without replacing expensive hardware of a building.