Patent GB-1132916-A (GB)
Title: Package forming and heat shrink banding apparatus
Inventor: COPPING BRUCE GRAY
IPC: B65B53/06
Filed: 1966-12-16
Abstract: 1,132,916. Wrapping and heat shrinking apparatus. GEO. J. MEYER MFG. CO. 16 Dec., 1966, No. 56437/66. Heading B8C Apparatus for operating continuously to enclose groups of articles in a heat shrunk film tube, includes means to form the tube about the articles, to divide them into groups and to shrink the tube about each group. The shrinking may be performed in two stages by successive heating tunnels and the latter are raisable above the article path to prevent overheating when the article feed is stopped. Cutting of the tube may also be in two stages. Tubing the film.-Articles e.g. cans are fed in beneath conventional tube forming means 8 which folds a web about them to overlap beneath and be sealed by a retractable heated moving belt 12. A cardboard &c. top element 5 for each package may be placed on the incoming articles before they are enclosed. Dogs 29 on conveyer chains 28, press against the articles with rollers 30, 31, Fig. 3, through the film tube to form groups. The chains also carry slotted members 64, Fig. 1, which drive first cutting means by engaging studs 70 on a drum 66 comprising spaced discs carrying heated cutter bars 68, Fig. 3, and driving an upper similar drum 67. The bars cut the tube after a first shrinking process, completely along its upper and lower surfaces and part way only through its sides. Cold air may be blown on to the shrunk tube prior to cutting. Heat shrinking apparatus.-The heat shrinking is carried out in two stages by similar hot air tunnels 20, 90, Figs. 1, 6, 11, each straddling the path of the tube in the manner of a saddle and raisable by cylinder means 26, 126 respectively clear of the path. The tunnels, Figs. 6, 11, each have inner 21 and outer 22 walls, and blowers 38 and heaters 37, hot air being forced through apertures 40 in the inner wall on to the upper areas of the tube. The hot air also passes through aligned apertures 41, 42 respectively in the bottom walls 36 of the tunnel and in the machine bed plate 43 on which it rests, to a chamber having an apertured cover plate 48 and from thence it impinges on the lower areas of the tube. The air returns to the blowers via inner wall apertures 39 in end compartments delineated by walls 39a. In order to seal the heater space when the tunnels are raised, flaps 49 are provided, normally kept open by pins 51, Fig. 6, but swinging down to close the apertures 41 when the tunnel is raised. The ends of the tunnels are closed by opposed fixed plates 24a as they are drawn up between them and cam operated flaps (52), Fig. 5 (not shown), swing across the base of the tunnel as it approaches its uppermost position. Final shrinking and severance.-After the tube has passed the first cutting means it is taken over by upper and lower conveyer belts 80, 81. These carry dogs (82), Fig. 4 (not shown), which press between the groups and locate the cut edges of the tube adjacent the top and bottom of each group end during passage through the second tunnel. Before entering the latter, the packaged groups are wholly severed from each other by vertical cutting elements mounted on parallel motion link means (83, 87), Fig. 13 (not shown), to traverse circular paths intersecting the tube sides. Finally, at the exit from the tunnel 90, a punch 102 cuts finger holes in the package tops. The end view of the final package is shown in Fig. 10.