| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a manufacturing method that ensures a thin wall and required performance and can be inseparably combined with another member constituting a thrust needle bearing. <P>SOLUTION: A plate material 8a shown in (A) is hardened by heat treatment into a first intermediate material 12 shown in (B), and then the first intermediate material 12 is punched out to form a second intermediate material 13 shown in (C). The hardness of the second intermediate material 13 is partially decreased by high-frequency annealing to provide an annularly-annealed part 16 and partially-annealed parts 17, 17 and form a third intermediate material 14 shown in (D). The third intermediate material 14 is bent at the portion of the annularly-annealed part 16 to form a fourth intermediate material 15 shown in (E) and having a flange part 6a. A plurality of places at the edge of the flange part 6a are bent at the partially-annealed parts 17, 17 and is finished as a race 4a shown in (F). <P>COPYRIGHT: (C)2012,JPO&INPIT |
