Who first invented the bearing?

China is the first country in the world to invent rolling bearings. /kloc-at the end of 0/7th century, C. Vallow of Britain designed and manufactured the ball bearing, and put it on the mail car for trial use, and P. Worth of Britain obtained the patent for the ball bearing. /kloc-at the end of the 8th century, H.R. Hertz of Germany published a paper on contact stress of ball bearings. On the basis of Hertz's achievements, R. Striebeck of Germany and A. Parmgren of Sweden carried out a lot of experiments, which contributed to the development of design theory and fatigue life calculation of rolling bearings. Subsequently, N.P. Petrov of Russia applied Newton's viscosity law to calculate bearing friction. O. Reynolds of Britain made a mathematical analysis of Thor's discovery and derived Reynolds equation, which laid the foundation of hydrodynamic lubrication theory. Therefore, it was not invented by a specific person, but the crystallization of the wisdom of many people.