Linear bearing is used in conjunction with quenched linear transmission shaft. A system that moves in an infinite straight line. The load ball and quenched transmission shaft are in point contact, so the allowable load is small. However, when moving in a straight line, the friction resistance is minimal, the accuracy is high, and the movement is fast. Linear bearings are more and more widely used in electronic equipment, food machinery, packaging machinery, textile machinery, instrument numerical control machine tools, automobiles and digital three-dimensional coordinate measuring equipment and other precision equipment or special machinery industries.