GB787802A - Method of and apparatus for packing liquid or paste-like substances in containers ofsynthetic thermoplastic material - Google Patents

Abstract

787,802. Moulding capsules. FARBWERKE HOECHST AKT.-GES. VORM. MEISTER, LUCIUS & BRUNING. March 12, 1954 [March 12, 1953], No. 7334/54. Class 87(2). [Also in Group XVII] Capsules filled with liquid or paste are produced by positioning sheets or webs 1 and 2 of synthetic thermoplastic material between a lower fixed clamping frame 3 and an upper vertically-movable clamping frame 4 in which are slidably mounted gridlike electrodes 5 and 6 fitted with moulding elements 7, 8 defining opposed cavities. The frame 4 is then moved downwardly to clamp the edges of the sheets, the electrodes are moved inwardly to the position shown and a filling nozzle 9 is moved to the right into sealing engagement with edge portions of the sheets which overlie a conical charging opening formed by mating recesses in the frames 3, 4. The liquid or paste, which may be heated, is then forced between the sheets through the nozzle so that the sheets are expanded into the moulding cavities, the electrodes are moved further inwardly to expel excess material which escapes through a valve 10, the nozzle 9 is retracted and, if desired, the upper frame 4 is moved upwardly a short distance. Welding of the sheets is then effected by applying a high-frequency voltage to the electrodes and moving them inwardly a further short distance to compensate for the difference between the combined thicknesses of the unwelded sheets and the thickness of the weld. The filled capsules thus formed are separated or partially separated by knives 11 operating in recesses 12 in the electrodes or cutters formed on the electrodes, after which the electrodes and upper frame 4 are retracted to allow the capsules to be removed or ejected. If the capsules are formed from webs and are not completely separated, reciprocating grippers may be used to remove the chains of capsules from between the frames and at the same time feed fresh portions of the webs into position for filling and welding. The elements 7, 8 are preferably made of dielectric material and formed with air escape passages 15 which may also be used for the supply of compressed air to eject the filled capsules. The elements 8 may be provided with adjustable spring-loaded buffers 14 which determine the volume of excess filling material displaced when the electrodes engage the sheets. Alternatively, the elements 7 and 8 may be made of metal and suitably embossed or engraved so that designs or indicia are formed on the surfaces of the capsules. The sheets 1 and 2 may be preheated and, in the case of thick sheets, premoulded by the admission of compressed air before the filling operation.