| 摘要 |
PURPOSE:To concurrently forming the flange, projection parts, rugged grooves of a flange round metal bar and to reduce the stages by press fitting a bar stock into a lower die which plural recessed parts are carved on the top face of the die and plural vertical grooves along the axial direction are carved on the inner peripheral surface of the upper end part of the hole part of the die. CONSTITUTION:At the time of press fitting a bar stock into a lower die by an upper die, a flange 1 of the stock is formed and projecting parts 2 are formed on the back face of the flange 1 by a recessed part carved on the lower die. Further, a shaft part 3, on which rugged grooves 4 along the longitudinal direction in the underhead part below the flange 1 are formed by vertical grooves carved on the inner peripheral surface of the upper part of the hole part of the lower die, is formed. Thus, the flange, projection parts, rugged grooves are concurrently formed, so that a stage such as knurling is eliminated and the manufacturing cost is reduced.
|
