| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing outer and inner rings by which the outer and inner rings can be manufactured out of the same round bar, the manufacturing time can be shortened by simultaneously forming works for cutting and grinding the outer and inner rings out of a single disk-like bulk by cold forging, and the yield of the material is improved. SOLUTION: The round bar 1 is cut to a predetermined thickness orthogonally to the axis thereof to form a disk-like bulk 2 <; S1>;, a center recessed part 5 and a circumferential groove 6 are formed by cold forging on a flat side of the disk-like bulk <; S2>; and <; S3>;, the center recessed part 5 is punched to form a center hole 12 <; S4>;, the circumferential groove 6 is punched to separate the groove into the inner and outer rings <; S5>;, a work 15 for working an outer ring on the outer side of the ring shape, and a work 16 for working an inner ring on the inner side thereof are formed <; S6>; to manufacture an outer ring 17 and an inner ring 18. |
