GB928606A - Folding box for use in wrapping machines - Google Patents

Abstract

928,606. Wrapping. FORGROVE MACHINERY CO. Ltd. May 30, 1961 [Aug. 24, 1960], No. 29266/60. Class 94(1). The folding box of a wrapping machine, of the type in which a web of wrapping material is folded into tube form about articles placed successively thereon and then opposed walls of the tube are sealed together between the articles, is arranged to produce the longitudinal joint at a bottom corner of the tube. The folding box 13 comprises a flat base 14; a long side wall 15 having a sloping folding edge 16; a short side wall 17 located near the exit end of the box and having a folding edge 18; and a top 19 having a folding edge 20 joining the upper ends of the folding edges of the side walls. A web 10 of wrapping material is fed to the box 13 from a drum 11; articles are dropped periodically on to the web at a position L. In passing through the box 13 the web 10 is folded over by the edges 16, 18, 20 bringing its marginal portions together adjacent the bottom edge of side wall 17. Two forms of box are described which produce a lap joint and a fin joint respectively. The fin joint may be sealed by rollers 22 and a plough blade 23 then folds it flat against the package. No provision is made to seal the lap joint. The tube passes to sealing heads 26 which move in to grip the tube intermediate the articles 28. Heat is applied to seal the tube transversely and simultaneously the heads 26 move towards the dotted position. The web 10 is by this means drawn through the folding box 13. Reaching the end of their travel the heads 26 release the tube and move back to their original position to repeat the process. A knife 27 is included in the sealing heads 26 to separate successive packages. In a modification of the box, Fig. 9 (not shown), the upper wall of the box is open, the folding edge consisting of a telescopic rod 120 allowing the box to deal with articles of various sizes.