| 摘要 |
Machinery for dispensing and welding tubular thermoplastic film to make sacks, where the tubular film is flat but has longitudinally creased borders. The equipment has welding bars not only to produce transverse welds for the base of the sack but also local welds which maintain the sidewall folds in position during isolation and filling of individual sacks. Esp. for mfr. of box or semi-box section sack for holding bulk quantities of powdered or granular materials which can be loaded through a bag mouth which is only partially open. The ancillary welds prevent the mouth and edges of the bag adopting variable shapes which may be difficult to grip and move by automatic machinery, e.g., to transfer individual bags to subsequent filling and seal welding stations, etc. |
