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 orbit grooves of the two races are non-circular and the orbit groove coefficient F.sub.1 of the outer race is smaller than the orbit groove coefficient F.sub.2 of the inner race. 
Nippon Seiko Kabushiki Kaisha
F F F
F16C F16C F16C
inventional inventional additional
Hisashi Yukihiro Shuyou Yukio
Satoh Akabane Tsuchiya Shiraiwa