Shapiro and Shapiro
Ball bearing
 In a ball bearing including an outer race, an inner race and ball-like rolling members interposed between the two races, the outer race has a single arcuate orbit groove and when the orbit groove coefficient of the inner race is expressed as ##EQU1## where .rho..sub.0 is the curvature radius of the groove bottom of the orbit groove of the inner race, .rho..sub.1 is the curvature radius of the groove edge of said orbit groove and D is the diameter of the rolling members, EQU 10.ltoreq.F.ltoreq.70. 
Nippon Seiko Kabushiki Kaisha
F F F
F16C F16C F16C
inventional inventional additional
Shuyou Yukio Yukihiro Hisashi
Tsuchiya Shiraiwa Akabane Satoh