GB842927A - Method of and means for filling bags of thermo-weldable material - Google Patents

Abstract

842,927. Packaging. PLASTUS S. A. July 17, 1957 [July 20, 1956; Nov. 24, 1956], No. 22638/57. Class 94(1). In a method of closing a filled theremoplastic sheet bag, the bag is clamped along spaced lines adjacent the mouth and the material heatsealed between the lines. Means may be provided to remove gas, air or part of the packaged product trapped between the lines. In some embodiments of apparatus for performing the method, Figs. 1-5 (not shown), jaws having resilient facings clamp the bag mouth about one or more filling tubes, and further jaws clamp the bag beneath the mouth, any trapped product being removed through the tubes. The heat sealing elements pass between the upper and lower jaws. In apparatus for forming a continuous succession of packages, two webs 12 joined along their margins by sealers 13 are gripped and sealed transversely, after filling with liquid from a nozzle 14, by members 19a, 19b, 20 on vertically reciprocating jaws 16. The jaws 16 may also advance the web. As the jaws close on the filled tube, it is clamped by the elements 19a, 19b, a needle 24 being gripped by the latter and pulled downwards relative to a fixed cylinder 26 as the jaws 16 descend. The needle 24 is attached to a piston 25, movement of which in the cylinder 26 causes liquid between the clamped areas to be evacuated. The sealing members 20 then advance to form spaced seals 21 between which the packages are severed. Plates 29 prevent undue bulging of the tube. In a modification on which solid products 30 are packaged, members 31 first contact the tube after filling. A pusher 32 and a suction plate 33 are brought into contact with the tube, the application of suction via passages 34 causing a needle 35 to penetrate the web. Air is then withdrawn from above the product by suction, and, if desired, inert gas introduced by the needle. Members 36 now clamp the tube and trapped gas is removed by the needle, followed by sealing by members 37. The tubes may also be formed by folding a single web or by extrusion.