| 摘要 |
PURPOSE: A rack bar manufacturing device is provided to improve the forming precision of a rack bar by dispersing stress concentrated on the center of teeth of a rack bar through a concave portion of a side punch. CONSTITUTION: A rack bar manufacturing device comprises a lower die(118), an upper die(112), and a pair of side punches(126,132). A rack bar(10) is placed on the lower die. The upper die moves up and down relative to the lower die to form teeth on a rack bar. The pair of side punches press the side of the rack bar by obliquely moving from the top to the side of the lower die. The side punches have a concave portion facing the side of the rack bar, where the length of the concave portion is shorter than that of the rack bar teeth. |
