VACUUM PACKAGING: CLAMPS GRIP COVERING AND SUPPORT WEBS TO PRODUCE WRINKLE FREE COVERING WEB

摘要

A packaging method and apparatus employ (i) a thermoforming station 6 through which a support film web 4 is advanced by means of an endless chain carrying clamps 16, followed by (ii) a loading station (A) in which product articles are inserted into the trays formed by the thermoforming station, and (iii) a film-combining station B at which a covering film 3 is stretched longitudinally and then applied in its stretched configuration to the support web 4 (with or without the above-mentioned thermoformed trays) and is clamped thereto for subsequent vacuum skin packaging of the product articles (at C) between the support web 4 and the upper film 3 by a process similar to that disclosed in EP-A-0270208. The resulting vacuum skin packs from such a process and apparatus are wrinkle free whereas the conventional vacuum skin packs exhibit longitudinal wrinkling in the covering film.