ES297484A1 - Packaging machine - Google Patents

Abstract

A machine for vacuumizing and gassing a filled container includes an open-ended treating chamber conveyed along a pre determined path, means for positioning a container therein and closing the chamber lower end and a cover for the cham ber upper end which seals in during a major part of its move ment during which period air is removed from the chamber and replaced by an inert gas after which said cover is re moved before the chamber reaches a container closing zone A turret 11 intermittently driven by a Geneva gear is pro vided with an annular plate carrying a plurality of chambers 14. Positioned below the chambers are the container supports and bottom sealing members 13 which are raised into contact with the chambers by means acting on shafts 136. The chamber covers 16 are secured to a chain 17, dependent from a fixed support plate 56, and are driven around the outside of a track 181, Fig. 2 (not shown), so that they are positioned over the chambers, except in the vicinity of the closing zone B where they are diverted by a sprocket 189. The covers are capable of being moved vertically relative to the chain. Containers C with loosely fitted lids are fed on to the supports at A by e.g. a star-wheel. The supports are raised on to an upper cam track 48 by a platform 282 elevated by a piston 283, to position the containers in the chambers and seal the lower ends. The covers are urged downwards to seal the top of the chambers by followers 219 running on the cam track 222, Fig. 6 (not shown). The chambers are connected individually to a manifold 231 at the hub of the machine for communication with sources of low vacuum, high vacuum and inert gas, e.g. nitrogen or carbon dioxide respectively. At the closing zone each container is raised towards the closing head 19 on a plate 167 in the support means 13 mounted on a shaft 146, Figs. 4, 5 (not shown), within the shaft 136. A T-shaped slot 176 cut through the end of both shafts 136 and 146 receives a mating head 177 narrow enough to engage only shaft 146. A piston 178 raises shaft 146 to present the container to the closing head above the top of the chamber. Correct registration below the head is ensured by engagement of the shaft housing 141 by a piston operating locating rod 277. An annular plate 266, Fig. 1, is spaced above the container at the closure zone and the inert gas supplied to the head to prevent re-entry of air into the containers. After closing the containers the shaft 146 is lowered to reposition the container in the support. The support 13 is then lowered on to cam track 44, before the discharge position D is reached, by an arcuate T-shaped head 287 engaging the T-slot in both shafts. In order to accommodate containers of different sizes the top portions of the chambers 14 are replaceable, and the cover support plate 56 may be lowered.