| 摘要 |
<p>PURPOSE:To omit the trouble of stripping and trimming after forming while preventing the generation of lugs by using the cylindrical bottomed preform provided with a notch on the opening end of a cylindrical side part or on the inner surface adjacent to said opening end. CONSTITUTION:A cylindrical bottomed preform 1 is composed of the cylindrical side wall 2 integrally molded by injection molding of plastic, etc., and the bottom part 3 connected to its lower end, and then the upper part of the cylindrical side wall 2 has an opening end 4. This preform 1 has a notch part 5 on the opening end 4 or on the inner surface adjacent thereto. The preform 1 is supported by a punch 10 temporarily inserted. The wiping die 11 movable in the direction of the same axis as this punch 10 is provided. When the punch 10 is moved lower, the cylindrical side wall 2 of the preform is thinned to a controlled thickness, while the side wall 2 is engaged with the working tip part 12 having a smaller inner diameter than the outer diameter of the side wall 2. Thus, the notch 5 is provided on the opening end 4 or on the inner surface adjacent to the preform, and the generation of lugs on the upper edge of a squeezed drawn can can be prevented.</p> |
