| 摘要 |
PURPOSE:To easily tear an opening piece, by forming a thin opening piece for pinching an important part of a can body and making it project downward, and a gnawed groove, subsequently, bending it upward, and constituting so that a plate between a cut guide groove and the gnawed groove becomes thin. CONSTITUTION:On a lower mold 6, a hollowed seat 8 whose inside circumference has been formed to a downward tapered surface 7 is provided, and on the upper surface circumferential edge of the hollowed seat 8, a projecting streak 9 is provided. A projecting part 14 whose tapered surface 12 and lower surface 13 have been flattened is provided on an upper mold 10, too. An iron plate material is pinch-pressed by both these molds 6, 10, a part of a cover body 1 is projected downward, and a gnawed groove 16 is formed on a dish-like opening piece 2 having a thin consecutive piece 15 which is evolutely inclined downward, on the circumferential edge part, and its lower surface circumferential edge part. This cover body 1 is pressed by use of other molds 21, 23, the cover body 1 and the upper surface of the opening piece 2 are set on the same plane, the thin consecutive piece 15 is bent so as to have a V-section, in a hollowed groove 19 of the lower mold 21, and a cut guide groove 5 having a V-section is formed between the upper surface of the cover body 1 and the upper surface of the opening piece 2. |
