Elevator is a vertical movement of the elevator, the direction of operation of the escalator inclined, inclined or horizontal direction of the general movement of the moving sidewalk. With the elevator, the skyscraper was able to rise, the modern city was able to grow taller. Today, the elevator has become a modern human life in the widespread use of vertical means of transport. People on the elevator safety, efficiency, comfort and constant pursuit of the elevator technology to promote progress.
In fact, long ago, people use some of the original lifting tools to transport people and goods.
Before and after 1100 BC, the ancient Chinese invented the windlass, which uses reels to complete the lifting movement movements, thus increasing the height of the items to enhance. In 236 BC, the Greek mathematician Archimedes designed and manufactured by the winch and pulley group consisting of lifting devices. The driving force of these lifting tools are generally human or animal power. In the early 19th century, in Europe and America began to use the steam engine as a lifting tool power. In 1845, William Thomson developed a hydraulic-driven lift, the hydraulic drive medium is water. Although lifts were being improved by a number of innovative engineers from generation to generation, lifts that were universally accepted by the industry did not appear until 1852 when the world's first safety lift was born.
In 1852, the United States of New York Yanks (Yonkers) mechanical engineer Mr. Otis invented the world's first one Safety lifts. It is powered by a steam engine, equipped with a safety device lifts. He fixes the serrated iron bar on the guide rail, and a spring piece is arranged on the upper part of the car and connects it with the mechanical linkage and the brake pawl. The hoisting rope is fixed in the center of the spring piece, and when the traction rope breaks, the spring piece restores the original shape, forcing the mechanical linkage device to move, and then the brake claw extends into the serrated iron bar to prevent the elevator from falling. Industrial users (freight elevators) are the first users of safety lifts.
In 1889, the elevator began to use electric drive,Really appeared in the elevator. Elevator in the drive control technology development has gone through DC motor drive control, AC single-speed motor drive control, AC two-speed motor drive control,DC with or without gears, gearless drive control, AC voltage regulator drive control, AC variable frequency drive control,AC permanent magnet synchronous motor drive speed control and other phases. The end of the 19th century, using Ward - Leonard system-driven DC elevator control appears, so that the elevator running performance improved significantly. At the beginning of the twentieth century, AC induction motor-driven elevators began to emerge, and subsequently the grooved (i.e., traction-driven) elevators replaced the drum-driven elevators and laid the foundation for long lifts and modern elevators with high safety basis. The first half of the 20th century, DC speed control system in high-speed elevator occupies a large proportion.
Today, the world's elevator companies are constantly on the elevator new research and development, maintenance and repair lift service system improvement, and strive to meet the growing demand for modern building traffic.
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