| 摘要 |
PURPOSE:To prevent the production of fuzz, by forming a specific hole and a cut by punching, and then pressing circumferential parts of the hole and cut, and heating a jacket while projecting the cut part of a liner to the hole and cut, and shrinking the projected part. CONSTITUTION:The jacket S having the hole and cut is clamped between a press plate 7 and a receiving die 8 and heated by a heating die 9. In the heat treatment, the jacket S is retained by the press plate 7 and the liner 3 folded into two is sandwiched between both folded sheet pieces 2b and 2c tightly; and heating die 9 is inserted into the hole 7D of the press plate 7, hole D' of the jacket S, and hole 8D of the receiving die 8 to heat the jacket. A gap V is formed between the inner circumferential surfaces of the holes 7D and 8D and the outer circumferential surface of the heating die 9. Consequently, fuzz in the hole shrinks thermally to form a round surface R at the circumferential hole part of the liner 3. |
