It has been 158 years since the elevator entered people's lives. In 1854, at the World Expo in Crystal Palace, New York, American Eliza Graves Otis showed his invention to the world for the first time. He stood on the platform of the lift filled with cargo, ordered the assistant to pull the platform up to the height that the audience could see, and then signaled that the assistant cut the lift cable of the lift with an axe.
Surprisingly, the lift did not crash, but was firmly fixed in mid-air - the lift safety device invented by Mr. Otis played a role. "Everything is safe, gentlemen." Mr. Otis, standing on the platform of the lift, waved to the people watching. No one would have thought that this was the first safe lift in human history.
The history of humans using lifting tools to transport goods and people is very long. As early as 2600 BC, the Egyptians used the most primitive lifting system when building the pyramid. The basic principle of this system has not changed yet: that is, while the balance is falling, the load platform rises. Early lifting tools were basically powered by manpower. In 1203, a crane-powered crane was installed in a monastery on the French coast, which ended the history of manpower transporting heavy loads. After the British scientist Watt invented the steam engine, the crane device began to use steam as the power.
Immediately thereafter, William Thomson developed a hydraulically driven lift with a hydraulic medium of water. Based on these lifts, generations of innovative engineers are constantly improving the technology of the lifts. However, a key safety issue has never been resolved. That is, once the lift cable is broken, the load platform must crash.
Mr. Otis’s invention completely rewrote the history of human use of lifting tools. Since then, the lift is no longer a "game of the brave", and the lift is widely used worldwide. In December 1889, Otis Elevator Company of the United States created a veritable elevator. It uses a DC motor as its power to drive the rope wound on the reel through a worm gear reducer to suspend and lift the car. In 1892, the American Otis Company began to use the button control device to replace the traditional car to pull the rope to control the way, the first modernization of the manipulation mode.
Life continues, technology is developing, and elevators are improving. In the past 150 years, the material of the elevator has been changed from black and white to color, and the style is from straight to oblique. In the control and control, it is step by step – handle switch operation, button control, signal control, collection control, man-machine dialogue, etc. Parallel control and intelligent group control appear in multiple elevators; double-decker elevators show the advantages of saving hoistway space and improving transportation capacity; the appearance of shifting automatic walkway escalator greatly saves pedestrian time; different shapes - sector shape The triangular, semi-diamond, semi-circular, and full-circle sightseeing elevators keep the line of sight of the passengers in it no longer closed.
Nowadays, the world's leading elevator companies, represented by the American Otis Company, are showing their strengths, and continue to carry out research and development of new elevator products, and constantly improve the repair and maintenance service system. FM gating, intelligent remote monitoring, host energy saving, low noise and durability of control cabinet, and environmental protection of composite steel strip - a new type of elevator that gathers the latest scientific research achievements in the fields of machinery, electronics and optics, and is a cold building. Therefore, the brilliance of humanity is scattered, and people's lives are thus made better.
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