Machine for forming, filling and closing bags with a bag lifting device

A process of forming, filling, and sealing sacks, comprising:

• unwinding a plastic tube;
• cross cutting of the tube perpendicular to a principal axis of symmetry thereof to produce tubular pieces;
• forming a sack bottom at one end of the tubular piece;
• transporting the formed sack;
• reducing a distance between a product discharge opening of a product feed element and a bottom of the sack to be filled by lifting the sack, the distance-reducing step including (i) transferring to a control device information used to determine a filling level of the sack during a sack filling operation and (ii) regulating the distance between the product discharge opening and the filling level of the sack to maintain the product discharge opening at a target level below the filling level of the sack;
• filling the sack with the product through the feed element;
• and
• sealing the filled sack.

A machine for forming, filling, and sealing sacks, comprising:

• an unwinding device for a plastic tube;
• a cross cutting device that cuts the tube perpendicular to a principal axis of symmetry thereof to create tubular pieces;
• a bottom forming device for forming a sack bottom at one end of the tubular piece;
• transportation devices for conveying the resulting sacks through the machine;
• a filling station with a feed element for filling the sacks with a product;
• a device to reduce a distance between a product discharge opening of the feed element and the bottom of the sack to be filled, the distance-reducing device including a sack lifting device configured to lift the sack in the filling station such that a top edge of the sack is located above the product discharge opening of the feed element;
• a device to seal the filled sack;
• and
• a control device that (i) is connected to measuring instruments that transfer to the control device information used to determine a filling level of the sack, (ii) regulates the distance between the product discharge opening and the filling level of the sack based on material- and filling-specific target values that minimize mist formation in the product, and (iii) measures a weight of the filled sack to confirm that a desired quantity of the product is fed into the sack, and, if necessary, corrects the quantity that is fed,
• the discharge opening of the feed element being located below the fill level of the product in the sack during the filling of the sack.