| 摘要 |
PURPOSE: A process is provided to produce a box shape structure having folded edges without using a separated machine to fix edges after punching and bending the structure. CONSTITUTION: A metal sheet is produced by the steps of punching a metal sheet(5) for forming a center part(8) having foldable side limbs(9,10), bending the side limbs(9,10) to the center part for forming a certain box-structure and producing a box-shaped metal sheet having a seam which folds the edges. The punching process punches the contiguous parts of the side limbs(9,10) to form the elements(13,14) of a complementary tongue which comes to be a seam. Also, the bending process establishes the seam folded by butting the elements of a complementary tongue to be fixed each other between near limbs(9,10).
|
