Process and apparatus for filling containers under vacuum

A method of vacuum filling containers with pulverulent or granular materials in an apparatus comprising first and second fixed stations, weighing means, said first station having conveying means for conveying pulverulent or granular materials to said weighing means for weighing the materials and dispensing means for dispensing the weighed materials from the weighing means to the containers, said second fixed station having vacuum means for applying vacuum to the containers containing the materials and sealing means for sealing the vacuum sealed containers, and a turntable mounted for intermittent rotational movement relative to said first and second fixed stations, the turntable having a plurality of at least three openable/closable support means for respective containers, the support means being uniformly angularly spaced from each other, said first and second fixed stations being arranged proximate to said turntable, the angular spacing between said fixed stations being the same as that between said support means, the method comprising the steps of:

• placing an empty container in an open support means located at a loading station spaced upstream from said first fixed station relative to the direction of intermittent rotational movement and closing said support means;
• rotating the turntable to bring the support means into vertical alignment with said first fixed station;
• feeding materials from said conveying means into said weighing means until the accumulated amount reaches a predetermined weight;
• transferring the accumulated materials to said dispensing means;
• lowering the dispensing means so that a lower portion thereof is received in a neck of the container at the first fixed station;
• dispensing the materials into the container and simultaneously confining dust;
• stopping dust confinement and lifting off the dispensing means after the materials are dispensed into the container at said first fixed station;
• rotating said turntable to bring the loaded support means into vertical alignment with the second fixed station;
• lowering the vacuum means into sealing relation with the top of the support means;
• operating said vacuum means to apply a vacuum to the space between the vacuum means and the top of the support means;
• moving said sealing means towards the neck of the filled container and welding walls of the neck to seal the same;
• venting the space to the surroundings;
• lifting off the vacuum means;
• rotating the turntable through an angle corresponding to an unloading position;
• opening the support means and removing the sealed container from the support means;
• and
• rotating the turntable to bring the empty support means to a loading position.