ANALYSIS OF A MOTION OF A STEEL BALL RULED BY CONTACT WITH GROOVES ON UPPER AND LOWER TRACKS

Abstract

Generally, steel balls are used to maintain rolling contacts on grooves of ball screws and bearings. When the ball screws and bearings are actuating, the balls are revolving around the grooves' orbit and rotating around the axis through the balls' center. To clarify the friction and noise caused by the motions, it is necessary to analyze in detail the contact condition and motion of the ball. This paper discusses a calculation method of bearing balls' motion, based on an assumption that the balls' orbital revolution and rotation is ruled by their contact points with the rolling grooves. Theoretical analysis and multibody simulation show the relationship between the initial contact points and the two points contact balls' motion.