Filling and closing thermoplastic sacks

摘要

The side parts of the opening-edges of the sacks (1) are gripped by grippers (2-5). The sacks are filled by pipes lowered into the open sacks, and closed by a top welding-seam made by a welding appliance. Air is sucked out of the filled sack before the top is welded. The vacuum is measured, and suction stopped when a pre-set vacuum is reached. The suction pipe (6,8) is lowered and raised in the sack. Tong-shaped clamping strips (10,11) clamping the opening edges of the sacks possess cavities (12) gripping the suction pipe orifice. A raised and lowered measuring pipe (7,9) is arranged parallel with the suction pipe.