| 摘要 |
Process for forming a filling valve on a plastic bag produced from tubular pieces with side folds comprises (a) continuously extruding a thread of heat softenable plastics onto the continuous valve sheet, which is continuously withdrawn from a storage roller, (b) separting the valve sheets from the continuous sheet, (c) supplying the valve sheets to a labelling machine and (d) continuously operating the labelling machine so that the continuously moving tubular pieces are rolled onto their corner folds (2) to bond the valve sheet with the inside of the fold by means of the plastics thread. The process and apparatus enable the tubular pieces to be continuously transported during the placing of the valve sheets on the tubular pieces. This is less time-consuming than stepwise transportation, and requires less expensive apparatus. |
