GB597458A - Method and apparatus for continuous production of filled and sealed tetrahedral packages of paper or the like - Google Patents

Abstract

597,458. Tetrahedral packages. RAUSING, R. Aug. 20, 1945, Nos. 21249 and 21250. Convention dates, Aug. 17, 1944, and July 25, 1945. [Classes 94 (i) and 94 (ii)] Tetrahedral packages of paper or the like are continuously formed and filled by feeding a web about a former and sealing the longitudinal edges to form a tube which on leaving the former is successively flattened, sealed and cut off at places spaced apart in the longitudinal direction of the tube so that each section of the tube between two such places forms a package which is sealed at its lower end, filled through the former, and then sealed at its upper end, being flattened and sealed alternately in one and the other of two relatively perpendicular planes so as to assume approximately regular tetrahedral form. In one embodiment of the invention, a web 2 is fed over a cylindrical former 3 and its edge sealed by a plate 4. The tube 5 thus formed is fed downwardly by feed rollers, not shown, and is flattened and sealed at places spaced apart alternatively by one or the other of two sets of pressing members, '6, 7. The package 8 so formed is filled through a tube 9 and sealed at its upper end in a plane perpendicular to its lower seal, after which it is severed from the tube 5 by one of two sets of knives, 10, 11. In a modification, one set of pressing members and one set of knives are used, which rotate through 90 degrees between each operation. In a further modification, the web is fed on to the former obliquely so that the longitudinal edges form a helical seam, and the tube so formed rotates around the former through 90 degrees while being axially displaced the depth of one package, so that the flattening and severing operations can be performed by one set each of pressers and knives, both non-rotatable, or by two sets each of pressers and knives acting in perpendicular planesand all rotating with the tube. The former may be cylindrical and flattened from its centre in relatively perpendicular planes towards its opposite ends; the tube is thus flattened before the action of the pressers. This type of former can be used also with a tube having a longitudinal seam. In a further modification, an even number of sets of pressers operating in alternately perpendicular planes may be used, to form two packages simultaneously, the knives being associated with the pressers and adapted to operate automatically at the correct times. The tube may be kept filled with liquid by a pipe or other means to a height above the top of the formed packages, so as to ensure continuous filling thereof.