GB801918A - An apparatus for applying a bayonet cover or a threaded cover to a container in the interior of which a vacuum shall be present when the cover has been applied thereto - Google Patents

Abstract

801,918. Applying closures to containers in vacuo. SONDERBYS FABRIKER AS. May 8, 1957 [Sept. 10, 1956], No. 14686/57. Class 125(2). In apparatus for applying bayonet or screw caps 32 to containers 33 in which a vacuum bell 2 mounted on a guide rod 1 encloses the container on its support 4, the lower end of the guide rod is provided with means to hold the cap, the container can be rotated relative to the cap, and clamping means for the container are actuated by the vacuum within the bell. As shown the clamping means comprise resilient pads 31 carried on the rods of pistons working in cylinders 27 the outer ends of which are open to atmosphere. When the bell is under vacuum, the pistons are drawn in so that the container is clamped. When the vacuum is broken, light springs retract the resilient pads. The upper part of the bell forms vacuum and vent chambers 10, 11 around the guide rod which is provided with passages 15, 34. The head forms part of a rotating table machine provided with a cam acting on a fork 6 to raise and lower the bell. Initially with the bell fully raised, outlet 36 of passage 34 communicate with vacuum chamber 10 so that a cap is retained by vacuum against a resilient ring 37 on the bottom of the guide rod. As the bell descends, the outlets 35 clear the chamber 10 and the cap is then held by a ring 17 mounted in a cup-shaped part 16 slidable on the lower end of the guide rod. Next, passage 15 communicates with vacuum chamber 10 and the bottom of the bell seals against the support 4 so that the bell is evacuated, thus actuating the clamping pads 31. A cam on the machine then rotates guide rod 1 by acting on an arm 41 so that the cap, gripped by ring 17, is screwed on. The stem 18 of support 4 then rides on to cam 40 so that the bell is lifted to put passages 15 in communication with vent chamber 11 so that the vacuum is broken. As the bell is raised once more to its highest position a flange 42 on the bell lifts the cup 16 slightly to open passage 43 thus ensuring that the passage 34 is vented. In a hand-operated modification, Fig. 1 (not shown), the guide rod is fixed and the support 4 and vacuum bell are rotated by a hand-lever which also raises the support slightly at the appropriate time to break the vacuum.