| 摘要 |
PROBLEM TO BE SOLVED: To surely realize the penetration and insertion of a nozzle for introduc ing compressed air between sheets and in a closed space even in a thin-walled hollow molded body by a method wherein both the sheets are clamped so as to make the enclosed space airtight through sealing members for forming airtightness provided on the sheet contacting surfaces of a spacer. SOLUTION: By pinching the peripheral edge parts of two thermoplastic synthetic resin sheets 1 and 2 from above and below by clampers 4 and 4 through a spacer 3, on both the upper and lower sides at the middle corresponding to a forming material of which sealing members S1 and S1 for forming airtightness are provided, both the sheets 1 and 2 are held horizontally and parallel to each other at regular intervals so as to leave an enclosed space 5 between them. Then, both the sheets 1 and 2 are heated from above and below with heaters 6 and 6, resulting in softening. At thus time, by blowing compressed air in the enclosed space 5 through an air nozzle 7 provided at some part of the spacer 3, both the sheets 1 and 2 can be pre-tensed in the direction separating from each other. |
