| 摘要 |
PURPOSE:To reduce man-hours and enhance the yield of material by forming a pair of lugs of a veneer at the edge of the cut-off part of a hub made from a metal sheet, and constructing the surrounding of a screw hole provided in either lug with a plate thickness greater than the tubular portion of the hub. CONSTITUTION:A workpiece 25 is punched off from a metal sheet, and a pair of tabs 4 are formed at a single side of a rectangular plate 2 while lugs 7 formed at the two ends thereof. A hub tubular portion 11 is formed in a part of this rectangular plate 2, and the tabs 4 and lugs 7 constitute a pair of parallel protrusions stretching in the axial direction at the cut-off edge of the hub tubular portion 11 for fastening of bolt and a fork prong 12, respectively. From one side a minor dia. punch is driven in the position mating with a screw hole 16 bored in one of the lugs 7 to form a boss 9 on the opposite side. This reinforces the screw hole 16 to accomplish certain bolt fastening. |
