抄録
In this paper, a new theoretical relation between the life and the load of a ball bearing is proposed basing on the same meaning of that of a roller bearing previously reported. The new equation obtained is based on the Heltz's equation and the empirical formula determined by "Degree of Fatigue" which is caused by the repeated stress on the contact surface and the frequency of the contacts. It has been confirmed by this calculation that the curvatures of the contact points are more effective than the other factores for bearing life.