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The historical development of bearings
Release time :2014-06-10

Early forms of linear motion bearings, is placed in a row of pry plate under a row of wooden poles. Modern linear motion bearings is using the same principle, but sometimes a ball instead of roller. The simplest is the rotation of the bearing sleeve bearing, it is just a between wheel and axle bushing. This design then is replaced by rolling bearing, is to use a lot of cylindrical roller instead of bushing, each as a single wheel roller.

Nanoscale lake in Italy found a ship built in 40 years BC in ancient Rome, was found early examples of ball bearing: a wooden ball bearing is used to support the rotary table. Leonardo Da Vinci is said to be in 1500 years or so have been carried out on a ball bearing description. Immature factors of ball bearing, it is important the ball collide, causing additional friction. But can put the ball in a small cage to prevent this phenomenon. Galileo in the 17th century, the ball is installed "cage" the description of the ball bearing done first. In the UK at the end of 17th century, c. the warrens design and manufacture of ball bearing, and in a coach on the trial and the p. worth taken out a patent on ball bearings. The earliest into practical rolling bearing with retainer is the clockmaker John harrison invention for making H3 timing plan in 1760. In Germany at the end of the eighteenth century H.R. Hertz published papers about the ball bearing contact stress. In Hertz achievement, on the basis of Germany's r. a. terry baker, Sweden PAM glen and others A lot of tests have been carried out, to develop the design of the rolling bearing theory and fatigue life calculation. Subsequently, the Russian N.P. petrov Newton's law of viscosity are used to calculate the bearing friction. The first patent on ball track is card masson Philip comic actor in 1794.

In 1883, friedrich fisher put forward using the appropriate production machine manufacture the same size and roundness accuracy of steel ball, laid the foundation of the bearing industry. Britain's o. Renault mathematical analyses of thor's findings, the Reynolds equation is derived, from then on, laid the foundation of hydrodynamic pressure lubrication theory.

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