Patent GB-1107579-A (GB)
Title: Processes for making rectangular tubes and devices for performing the processes
IPC: B31B50/28
Filed: 1965-08-16
Abstract: 1,107,579. Packaging-machines. HOLSTEIN & KAPPERT, MASCHINEN FABRIK PHONIX G.m.b.H. 16 Aug., 1965 [20 Aug., 1964], No. 34938/65. Heading B8C. [Also in Divisions B5 and F2] An apparatus for producing rectangular tubes from a flat strip of material 1 comprises rollers 20, 21 which provide longitudinal grooves in the strip, a guide 26 for folding the strip longitudin ally, and a guide station 28 together with a welding sta tion 29 for shaping and seal ing longitudinal edges of the strip together. The tube is filled with a product and then separated into a number of packages with top and bot tom closures. The flat ma terial strip 1 is drawn from a supply roller 19, to pass between the rollers 20, 21 which impress on it five longitudinal grooves. The strip 1 then passes over a rigid guide, which turns over a longitudinal edge of the strip. A nozzle supplies hot air to the surfaces of the longitudinal edge just before the strip 1 passes between press rollers 23, 24, where the surfaces are welded together. The strip 1 then passes the guide 26 which folds the strip longitudinally about the groove (14), Fig. 6 (not shown), and over rollers 27 to the guide station 28 and the welding station 29. Between the rollers 27 and the guide station 28 a filling material supply pipe 30 enters the interior of the tube through a gap between the longitudinal edges of the strip 1. The guide station 28 has an internal rectangular guide (33), Fig. 21 (not shown), over which the strip 1 passes secured to the supply pipe 30, and a corresponding external guide (34), both made of or covered with an anti-adhesive material. For strips 1 of stouter material, the guide station 28 is provided internally with two pairs of rollers (35), Fig. 23 (not shown), instead of the guide (33), and externally with rollers (38) and rigid guides (36), (37). The rollers (38) may be driven through toothed wheels so as to feed the strip 1 through the guide station. The welding station 29 has an internal guide (42), Fig. 22 (not shown), and an external guide (43). The longitudinal seam is welded together by spring- urged rollers (44), (45), inside and outside the tube after the nozzle (49), Fig. 21 (not shown), has supplied hot air to the surfaces to be welded. A modification of the welding station 29, has a pair of external rollers (52), Fig. 24, 25 (not shown), mounted on rooking arms (53). One of the rollers (52) serves with an internal roller (50) for welding the longitudinal tube edges together. In an alternative method of forming a seam between the longitudinal edges, Figs. 26, 27 (not shown), the longitudinal edge of the strip, Fig. 11 (not shown), is not folded over until the strip 1 has been folded longitudinally, Fig. 12 (not shown). In this method, the guide station (28), Fig. 29 (not shown), has coacting pairs of external rollers (57) which effect the welding of the seam, Fig. 15 (not shown), after the coating material of the tube has been heated by hot air from a nozzle (58). The welding station 29, is secured to the supply pipe 30 and has a roller (61), Fig. 30 (not shown), secured to a rocking arm which abuts against one of four rollers (59) to seal the longitudinal seam of the tube, Fig. 9 (not shown). A hot air nozzle (63) is arranged above the rollers (61), (59) and heats the surfaces to be welded together. Seams.-The longitudinal seams are formed by connection of the longitudinal marginal portions (4), (5), Fig. 2 (not shown). The longitudinal marginal portion (4) is folded upon itself, and welded to the marginal portion (5) in a joint (7), with two longitudinal edges, lying side by side. The folding of the portion (4) may be effected either before or after the strip 1 is folded longitudinally about crease line (14), Figs. 6 and 12 (not shown).