Patent GB-1436118-A (GB)
Title: Method and an apparatus for producing filled bags
IPC: B65B9/093
Filed: 1972-06-02
Abstract: 1436118 Producing filled bags B O JACOBSEN 11 May 1973 [2 June 1972] 25785/72 Heading B8C A method of producing article-filled plastics bags wherein a continuous length 2 of flat bag members is successively advanced to a filling opening 18 the open edge portions being unbroken between the consecutive bag members 30  and being engaged by driving means 13, 15 to move the opposed open edges of the consecutive bag members along guiding means 12, 16 causing the said opposed open edges to be moved away from each other as they reach the filling opening 18, the bag members being filled through this opening 18 and successively separated from each other, is characterized in that the bag material is supplied from a reel 4 as an unwelded double layer plastics sheet length and that, before reaching the filling opening 18, the double layer sheet length is successively provided with transverse welding lines 29 confining said bag members 30. As shown, the upper edges 10 of the double sheet length 2 of plastics material, folded about its lower edge 6, are intermittently driven, one at each side, along a rail 12, by a pair of driven belts 13 towards a split rail portion which comprises two spaced rails 16 which are adapted to spread apart the upper edges 10 of the sheet as they are located beneath the opening 18. The latter is formed in a supporting plate 14 for the rail 12 and communicates with the lower delivery end of a hopper 20 provided with a shutter 22. Before it reaches the loading opening 18 the double sheet is formed into individual, open topped, bags 30 by providing the sheet with a vertical welding and cutting line 24 during each rest interval of the machine, the weld line 24 terminating at a point 28 somewhat below the upper edges 10 of the sheet 2, and a row of ventilating perforations 26 being formed at each side of each weld. When each bag 30 is located, with the edges 10 spread apart, beneath the hopper 20 it is supported upon a lower conveyer 32, the shutter 22 then being withdrawn to fill the bag with a predetermined amount of articles, such as potatoes, up to a level beneath the points 28. The filled bags then proceed a further step to a welding tool 33 which closes the upper end of each bag with a weld line 34 and separates the bag from an upper edge portion 34 of the sheet which is collected on a reel 36. A cutter, not shown, may be used to separate the portion 34. The unit for making the welding and cutting lines 24 and the perforations 26 is built on a self-contained subchassis and comprises a plate 40 movable by a cylinder 52 and a stationary plate 42 mounted on either side of the sheet 2 the plate 40 having mounted thereon an elongated welding-andcutting-electrode 44 located between, and slightly behind, the plane of the front faces of a pair of pressure lists 46, 46, corresponding counter lists 48, 48 being mounted on the fixed plate 42 which also carries a counter list 50 for the electrode 44. The perforations 26 are made by punch members 64 which have spring-loaded bushings 74 and are mounted upon the stationary plate 42, at each side of the lists 48, 48, 50, and complementary holes 60 in vertical beam members 62 on the movable plate 40, the tubular punch members 64 being connected, by tubes 70, 72, to a source of vacuum, or pressure, to remove the discs punched out of the sheet. The upper edge portion 34 of the sheet may be left on the single bags and be provided with a handle opening.