| 摘要 |
A double walled plastics article is made by feeding a pair of spaced sheets or a tube between a pair of vacuum moulds, drawing the sheets or tube into conformity with the vacuum moulds and moving the moulds together to fuse the formed sheets together at certain regions to produce the final article. If desired the vacuum forming may be assisted by hot pressurised air fed between the sheets or into the tube and a final pressure may be applied to the article, after the moulds have moved together, by a blowing tube which pierces a wall of the article.
|
