GB1333309A - Packaging method and apparatus - Google Patents

Abstract

1333309 Wrapping - up articles WINDMOLLER & HOLSCHER 19 April 1971 [2 April 1970] 25283/71 Heading B8C In a process of packaging items which have been compressed to form a parallelepiped, e.g. bag stacks, in which a wrapper M is applied around the compressed item to be packaged, the wrapper which is made from shrinkable plastics sheeting protrudes over the ends of the item and is folded down on to end faces of the item, the wrapper end portions then being closed and subsequently shrunk by a heat treatment. As shown, a stack St of bags is compressed, surrounded by a wrapping of thermoplastic sheeting and sealed along side edges by apparatus comprising a feed table 1, a press arm 2, an abutment 3 for the stack, a pusher 4 and a welding device 5 all as described in Specification 1,317,802. Pivotable movement of the abutment transfers the stack held by the wrapper M to a chain conveyer 15 where pairs of welding jaws 16, 16<SP>1</SP>; 17, 171 grip, flatten and weld protruding wrapper end portions. The next step of the conveyer moves the wrapped item into gas fuelled heating chambers 19 having in their lower portions a gas burner 20 and in their upper portions, an outlet portion 21 which faces each end face of a stack. Flow guiding plates 22 and adjustable restricting plates 23, 24, 25 control the flow of hot gases on to the end faces for shrinking the folded wrapper end portions. The gas supply to the burners is interrupted during advancing steps of the bag stacks by means of a solenoid shut-off valve 26 which is controlled by cams 29 on the conveyer which operate on switch 28, the cams being spaced apart by a distance corresponding to the length of each step of the conveyer.