In the early form of linear bearings, a row of wooden poles was placed under a row of skids.Modern linear bearings use the same principle of operation, except that sometimes a ball is used instead of a roller.The simplest rotating bearing is the bushing bearing, which is simply a bushing sandwiched between the wheel and the axle.This design was subsequently replaced by rolling bearings, which replaced the bushing with a number of cylindrical rollers, each of which acted as a separate wheel.
An early example of a ball bearing, a wooden ball bearing used to support a rotating table top, was found on an ancient Roman ship built in 40 B.C. in lake nani, Italy.Leonardo Da Vinci is said to have described a ball bearing around 1500.Among the various immaturity factors of ball bearings, one of the most important is that the balls will collide with each other, causing additional friction.But you can prevent this by putting balls in cages.In the 17th century, Galileo made the earliest description of "caged ball" ball bearings.At the end of the 17th century, England's c. wallow designed and manufactured ball bearings, which were put on mail trucks for trial, and England's p. worth patented ball bearings.The first practical rolling bearings with retainers were invented in 1760 by watchmaker John harrison for the H3 chronograph.H.R. Hertz of Germany published a paper on contact stress of ball bearings at the end of the 18th century.On the basis of Hertz's achievements, r. stribeck of Germany, a. palmgren of Sweden and others conducted A large number of experiments, which contributed to the development of design theory and fatigue life calculation of rolling bearings.Later, N.P. petrov of Russia used Newton's law of viscosity to calculate bearing friction.The first patent on the groove was granted to Philip vaughn of carmarson in 1794.
In 1883, friedrich fischer proposed the use of appropriate production machines to grind steel balls of the same size and accurate roundness, laying the foundation of the bearing industry.O. Reynolds of England made a mathematical analysis of thor's discovery and derived the Reynolds equation, which laid the foundation of hydrodynamic lubrication theory.