| 摘要 |
PURPOSE:To form a center hole and a reference plane in an outer race at high accuracy and form a groove of good concentricity by ironing inner diameter of the groove inserting a guide punch and a split mandrel into the groove of a coarse material, and then making ironing of outer diameter. CONSTITUTION:When an upper ram 8 goes down, a hexagonal columnar guide punch 2 enters between six segments 1 to form a mandrel and groove ironing of an outer race coarse material 4 is performed. Next, a center hole is formed on the bottom 9 of the material 4 and at the end of the shaft 10 by a projection 3 at the tip of the punch 2 and a center punch 11 on a cushion 7. Then, outer diameter of the coarse material 4 is ironed by an ironing die 5 to form a groove after the segment 1. After forming the groove, the upper ram goes up and the guide punch 2 comes out from the segmant 1. When the coarse material 4 comes out from the segment 1, the material 4 is knocked out on the die 5 by the cushion 7. |
