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        1. The Development History of Bearings


          Release time:

          2023-04-11

          One of the earliest countries in the world to invent rolling bearings is China, and the construction of axle bearings has been recorded in ancient Chinese books. From archaeological relics and data, it can be seen that the oldest bearing in China with the embryonic form of modern rolling bearing structure appeared in Xuejiaya Village, Yongji County, Shanxi Province from 221 to 207 BC (Qin Dynasty). After the establishment of New China, especially since the 1970s, under the strong promotion of reform and opening up, the bearing industry has entered a new period of high-quality and rapid development.

          The Development History of Bearings

          One of the earliest countries in the world to invent rolling bearings is China, and the construction of axle bearings has been recorded in ancient Chinese books. From archaeological relics and data, it can be seen that the oldest bearing in China with the embryonic form of modern rolling bearing structure appeared in Xuejiaya Village, Yongji County, Shanxi Province from 221 to 207 BC (Qin Dynasty). After the establishment of New China, especially since the 1970s, under the strong promotion of reform and opening up, the bearing industry has entered a new period of high-quality and rapid development.

          At the end of the 17th century, C. Warlow from England designed and manufactured ball bearings, which were tested on mail carriers, and P. Worth from England obtained a patent for ball bearings. At the end of the 18th century, H.R. Hertz from Germany published a paper on contact stress in ball bearings. On the basis of Hertz's achievements, R. Strerbeck from Germany and A. Palmgren from Sweden conducted extensive experiments, contributing to the development of design theory and fatigue life calculation for rolling bearings. Subsequently, N.P. Petrov of Russia applied Newton's viscosity law to calculate bearing friction.

          The British O. Reynolds made a mathematical analysis of Torr's discovery and derived the Reynolds equation, which laid the foundation of hydrodynamic lubrication theory. The early form of linear motion bearings was a row of wooden rods placed under the pry plate. This technology may be traced back to the construction of the Great Pyramid of Giza, although there is no clear evidence yet. Modern linear motion bearings use the same working principle, but sometimes balls are used instead of rollers. The earliest sliding and rolling bearings were made of wood. Ceramics, sapphire, or glass are also used, while steel, copper, other metals, and plastics (such as nylon, bakelite, Teflon, and UHMWPE) are commonly used.

          From heavy-duty wheel axles and machine tool spindles to precision clock parts, rotating bearings are required in many situations. The simplest type of rotary bearing is a sleeve bearing, which is simply a sleeve sandwiched between the wheel and axle. This design was later replaced by rolling bearings, which replaced the original liner with many cylindrical rollers, each rolling element acting like a separate wheel. The earliest practical rolling bearing with a cage was invented by watchmaker John Harrison in 1760 to make an H3 hour meter.

          Early examples of ball bearings have been discovered on an ancient Roman ship discovered in Lake Nami, Italy. This wooden ball bearing is used to support the rotating desktop. This ship was built in 40 BC. It is said that Leonardo da Vinci described a type of ball bearing around 1500. One of the various immature factors of ball bearings is that they may collide with each other, causing additional friction. But this phenomenon can be prevented by placing the balls in small cages one by one.

          In the 17th century, Galileo gave the earliest description of "fixed ball" or "cage ball" ball bearings. But for a considerable period of time afterwards, installing bearings on the machine was not achieved. The first patent for the ball groove was obtained by Philip Vaughn of Carson in 1794.

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