| 摘要 |
A method for producing hollow articles of thermoplastic material, comprising the steps of: placing a first sheet of thermoplastic material (12), heated at a plasticizing temperature, between two dies (18, 38) which define at least one cavity (20), placing a second heated sheet of thermoplastic material (14) above the first sheet (12), and closing the dies (18, 38) and injecting a jet of pressurised fluid for forming at least one cavity (16) between said sheets (12, 14). One of the said dies (18) has at least one needle (22) connected to a source of pressurised fluid and placed in correspondence with said cavity (20). After the deposition of the first sheet (12) a pressure is applied on the portion of the sheet placed in correspondence with said needle (22) so as to produce the perforation of the sheet (12) by said needle (22). <IMAGE> |
