GB1110701A - Receptacle capping machine and method - Google Patents

Abstract

1,110,701. Receptacle capping machine. LILY CUPS OVERSEAS Ltd. 8 June, 1965, No. 24277/65. Heading B8C. In a machine in which the mouth of a container is closed by placing heat-shrinkable film over it, with its margins extending beyond the container rim and heating the margins to shrink them on to the container walls, the sheet of film is held against the container mouth by a clamp which is movable from a position below a capping head to a portion within the head, where hot air is blown against the free margins of the film. The machine caps a number of containers simultaneously. In the embodiment, a tray 25, Fig. 1, of containers 26 is moved along a conveyer 27 to beneath a heating unit 21 where a web 28, e.g. of irradiated, biaxially orientated polyethylene, is drawn manually from a roll 29, over the open mouths of the containers. The unit 21, carrying the individual capping heads 24, Fig. 4, is then manually brought down on to the covered containers. As the unit 21 is brought downwards, the container mouths are first contacted by sponge rubber covered plates 145, Fig. 12 (not shown), carried by plungers 146 slidably mounted within the heads 24, The web is then cut between the receptacles by a grid-like arrangement of knives 50a, 50b, see also Figs. 6, 7 and 13 (not shown), attached to a bottom wall 80 of the unit 21, through which the capping heads 24 extend. Finally with continued downward movement of the unit, the receptacle mouths move within the heads where hot air, from a chamber 90, is directed through apertures 135 in the capping head walls, Fig. 14 (not shown), on to the margins of the film. Simultaneously, V-shaped cuts (160), Fig. 16 (not shown), may be made in the closures by correspondingly shaped knives (160), Figs. 14 and 15 (not shown), fixed on the ends of shafts 140, on which the plungers 146 slide, to permit release of gases emanating from the contents of the receptacles. The heating unit is formed by an insulated box, Fig. 4, separated into two chambers 90, 91 by a plate 78, to which the heads 24 are removably attached, and which has openings 92 through which air heated in the chamber 90 passes to the lower chamber 91 which is closed by the plate 80. Air, blown into the upper chamber by the blower 48, provided with a flap valve 172 to restrict or prevent inlet of air to the heating chamber when the unit is in its upper position, passes through apertures 92 in plate 78 to the lower chamber and then through the apertures 135. The knives and capping heads 24 are heated by conduction through the plate 80. The clamping plates 145 fall by gravity into their lowered position as the unit 21 is raised but may be spring biased into this position, Fig. 11 (not shown). In a modification, the knives 50a, 50b may be omitted and the bottoms of the heads 24 flared outwardly and their edges sharpened to provide the required knife edges. Reference has been directed by the Comptroller to Specification 827,246.