GB709454A - Improvements in or relating to a method of closing and a machine for forming a carton - Google Patents

Abstract

709,454. Making cartons. OSWEGO FALLS CORPORATION. Dec. 12, 1951, No. 29091/51. Class 18 [Also in Group XXX] Liquid tight cartons are made each from two blanks coated with thermoplastic adhesive, one blank being folded to tubular form about a mandrel and the other being placed on the end of the tube and its overlapping edges folded against and secured to the tube. The machine for making them comprises a turret carrying a series of radial mandrels against which the tube-forming blanks are positioned and carried past folding, end closure applying and sealing units to a stripping unit. Tube-forming blank feeding arrangement. The adhesive coated blanks 106 are fed from a stack (not shown) on to a chain conveyer 107, Fig. 5, and carried through a heating unit (not shown) to soften the adhesive. The conveyer 107 feeds each blank to a position above a mandrel 96 and an arm 630 aligris it against a stop. The blank is clamped to the mandrel 96 by a plate 124 mounted on the turret, and the mandrel carries it in a clockwise direction to the folding unit A. Folding unit. Checks 152, Figs 5, 21, at the entrance to the unit, fold about the 'mandrel parts of the blank 106 extending on either side of it, and transversely reciprocating plates 157, 158. Figs. 20, 21, fold the blank round that side of the mandrel opposite the plate 124, the plate 158 co-operating with an element 186 to pinch the blank against the mandrel and consolidate the longitudinal seam. A heater 206 is positioned in the unit. to ensure the adhesive at the upper end of the tube will be soft when the end closure is applied. End closure applying unit. The unit B comprises an end closure blank feeding arrangement consisting of a chain conveyer 310. Fig. 39. having carriers 315 into which a blank 300 is drawn from a stack 301 by a reciprocating suction cup 305. The conveyer carries the blank past a heating unit 35 to a transversely reciprocating pusher 352, Figs. 6, 39, which thrusts it into a guide 356 on the closure applying head, Figs. 6, 23, 28, 31. The head consists of a die 240, a plug 230 and clamping jaws 247-250. The head descends and the plug 230 clamps the blank 300 against the top of the mandrel while the die 240 folds its overlapping edges down against the carton tube 198. Jaws 247-250 move inwardly to clamp these edges firmly against the mandrel, a heater 229 activating the adhesive. The die opening is relieved at the corners 397 to cause folding of the corner excess end closure blank material against the sides of the carton. The jaws 249 and 247 are slotted to receive " overlapping " portions of the jaws 248, 250, the jaws 249 and 250 having protuberances (not shown) which press the respective end closure edge firmly about the tube seam, to avoid a possible leakage. Shoes 374, Fig. 6, and a projection 392 on the guide 356, Fig. 23, ensure that all four sides of the tube are" clamped against the mandrel prior to the securing of the end closure. Sealing unit. This unit C has a head similar to that of B, except that the guides 356 are omitted. It serves to further consolidate the joint. Stripping unit D. Here the cantons 198 are stripped from the mandrels, turned with their open ends upwards and positioned on two conveyers 546, 547, Fig. 9, for passage to a filling station (not shown): Spring biassed grippers 510 are carried on carriages 502, Figs. 5. 9, reciprocated on rails 500 on either side of the mandrels 96. The mandrels have grooves 514 and holes 515 preventing vacuum forming in the canton, as it is stripped. The stripped carton is received by pairs of blades 528 carried on a rotating frame 529, the frame being rotated through 90 degrees to position the carton in the path of transversely reciprocating blades 542. The blades 542 sweep the cartons alternatively to one side or the other of the machine to position them on the two conveyers. The mandrels are hollow and are cooled by liquid circulated through the turret hub. Specification 700,586 is referred to.