A web of a plurality of interconnected bags, a bag obtained from this web and a method of manufacturing said web and apparatus for executing said method

Claim 1

1 . A web of a plurality of interconnected plastics bags (27) with gusset folds formed from a tubular foil, at least comprising a central (4, 4a) and two outer longitudinal gusset fold edw - s (2, 3, 2a, 3a) which bound a first and a second gusset fold part, each bag (27) of said web comprising (a) a transverse bottom seal (12) (b) two first fold part seals (8, 9,; 10, 11) at both sides of the web foil, which first fold part seals always connect an outer foil layer (1a, 1b) with an opposite gusset fold part (6a, 5a; 6, 5), said first fold part seals extending between the central (4, 4a) and outer longitudinal fold edges (2, 3; 2a, 3a( in the region of said transverse bottom seal (12) and diverging from said bottom seal (12) to the outer fold edges (2, 2a, 3, 3a); (c) second fold part seals (13, 14; 15, 16) at both sides of the web foil which second foil part seals always connect an outer foil layer (1a, 1b) with an opposite gusset fold part (6a, 5a, 6, 5) said second fold part seals extending between the central (4, 4a) and outer longitudinal fold edges (2, 3, 2a, 3a) at the end of the bag remote from the transverse seal of this bag, said second fold part seals converging from the outer longitudinal fold edges (2, 3; 2a, 3a) to the transverse seal (12) of a subsequent bag (27) characterized in that at both sides of a bag an additional seal (30) extends substantially parallel to the fold edges and in the region between inner and outer fold edges, said additional seals (30) being connected with the second fold part seals (13, 14; 15, 16) and extending from said second fold part seals towards the transverse bottom seal (12) of a subsequent bag (27).

Claim 8

A method of producing a web of a plurality of interconnected plastics bags with gusset folds, at least comprising a central (4, 4a) and two outer longitudinal gusset fold edges (2, 3; 2a, 3a) which bound a first and a second gusset fold part by providing a continuously supplied tubular plastics foil by heatsealing with (a) first fold part seals (8, 9; 10, 11) whereby each first fold part seal always connects an outer foil layer (1a, 1b) with an opposite gusset fold part (6a, 5a; 6, 5) (b) at a predetermined distance from said first fold part seals with always at least two second fold part seals (13, 14; 15, 16) at both sides of the tubular foil which second fold part seals connect an outer foil layer part with the opposite gusset fold part; (c) first and second fold part seals are formed between the central and outer longitudinal fold edges and the first fold part seals converge from the outer fold edges to the central fold edge (4, 4a) and said second fold part seals converge from the outer fold edges to the central fold edge, and (d) subsequently the tubular foil as obtained under step (a) is moved over a predetermined distance and immediately after having reached another sealing position a transverse bottom seal is formed characterized in that an additional seal (30) is formed at both sides of a bag in the region between the inner (4, 4a) and outer (2, 3; 2a, 3a) fold edges and each additional seal extending substantially parallel to the fold edges is connected with a second fold part seal (13, 14; 15, 16) and extends towards the transverse bottom seal (12) of a subsequent bag.

Claim 9

A method of producing a web of a plurality of interconnected plastics bags with gusset folds, at least comprising a central (4, 4a) and two outer longitudinal gusset fold edges (2, 3; 2a, 3a) which bound a first and a second gusset fold part by providing a continuously supplied tubular plastics foil by heatsealing with (a) first fold part seals (8, 9; 10, 11) whereby each first fold part seal always connects an outer foil layer (1a, 1b) with an opposite gusset fold part (6a, 5a; 6, 5) (b) at a predetermined distance from said first fold part seals with always at least two second fold part seals (13, 14; 15, 16) at both sides of the tubular foil which second fold part seals connect an outer foil layer part with the opposite gusset fold part; (c) first and second fold part seals are formed between the central and outer longitudinal fold edges and the first fold part seals converge from the outer fold edges to the central fold edge (4, 4a) and said second fold part seals converge from the outer fold edges to the central fold edge, and (d) subsequently the tubular foil as obtained under step (a) is moved over a predetermined distance and immediately after having reached another sealing position a transverse bottom seal is formed characterized in that an additional seal (30) is formed at both sides of a bag in the region between the inner (4, 4a) and outer (2, 3; 2a, 3a) fold edges and each additional seal extending substantially parallel to the fold edges is connected with a second fold part seal (13, 14; 15, 16) and extends towards the transverse bottom seal (12) of a subsequent bag.

Claim 12

A method according to claims 7 to 9, characterized in that the additional seals (30) connect first and second fold part seals.

Claim 13

A method according to claims 7 to 10, characterized in that the additional seals (30) extend at both sides of a transverse bottom seal.(12).

Claim 14

An apparatus for executing a method according to claims 7 to 11, at least comprising conveying means for conveying a plastics foil, first sealing means for forming first fold part seals (8, 9; 10, 11), second sealing means for forming second fold part seals (13, 14; 15, 16) transverse sealing means for forming a transverse seal (12) characterized in that the apparatus comprises fourth sealing means for forming said additional seals (30).