In 1853, at the world's fair in New York's crystal palace, American eliza graves Otis showed his invention to the world for the first time. He stood on the elevator platform, full of goods ordered assistant pull platform up to the height of the audience can see, then sends a signal, the assistant with the ax cut off the elevator lift cables. Surprisingly, the escalator did not crash, but was firmly fixed in mid-air -- the elevator safety device invented by Mr. Otis played a role. "All safe, gentlemen." Mr. Otis, standing on the elevator platform, waved to the people watching. No one would have thought that this was the first safety elevator in human history.
Human beings have a long history of transportation of goods and personnel by means of lifting tools. As early as 2600 BC, when the egyptians build the pyramids with the rise and fall of the original system, there has been no change of the basic principle of the system: that is, a counterweight falling at the same time, the load platform. Early lifting tools are primarily human powered. In 1203, a donkey powered crane was installed in a convent on the French coast, ending the history of carrying heavy objects by hand. After the British scientist watt invented the steam engine, the crane was powered by steam. Then, William Thomson developed a hydraulically powered elevator. The hydraulic medium was water. On the basis of these elevators, generations of innovative engineers have been improving the elevator technology. However, a key safety issue has never been resolved, which is that the load platform will have a crash if the lift lifts the cable to fracture.
Mr. Otis's invention has completely rewritten the history of the use of tools. From then on, the lift ladder was no longer a "game of the brave", and the elevator was widely used worldwide. In December 1889, the United States Otis elevator company created a veritable elevator, it USES the dc motor as the power, through the worm gear reducer drive winding rope on the drum, suspension and lifting capsules.
Life continues, technology is developing, and elevators are improving. For 150 years, the material of the elevator by black and white to color, style by the straight type to the oblique type, particularly in handing control of the new step by step - handle switch control, push button control, signal control, collection control, man-machine dialogue, etc., still appeared many elevators in parallel control, intelligent group control; The double deck elevator shows the advantages of saving the well space and improving the transportation capacity. The emergence of a variable speed automatic sidewalk escalator greatly saves the time of pedestrians. The different shapes -- sector, triangle, half diamond, semicircle, and circular elevator -- make the passenger's line of sight no longer enclosed. FM door control, intelligent remote monitoring control cabinets, host, energy saving, low noise and durable, composite steel belt environmental protection - a leisurely contributions of the human in the field of mechanical, electronic, optical and other latest scientific research achievements of new elevator to come out, cold buildings scattering humanity, therefore, the life of people so better.