The top surface of a platen is provided with a plurality of apertures, leading to a vacuum chamber therein, and a plurality of protuberances extending upwardly therefrom, the apertures and protuberances being arranged as grids extending over the top of the platen. A first plastic film is placed on the platen top, leaving apertures and protuberances beyond the periphery of the first plastic film uncovered, the said film draping around those protuberances covered thereby, and being dimpled upwardly thereby. The article to be packaged is placed on the first film and a second plastic film is placed over the article and over the first film, covering the entire platen top, draping around those protuberances not covered by the first film so that the underside of the second film lies directly over those apertures not covered by the first film. The second film lies substantially flat across the tops of the dimples in the first film because of atmospheric air therebetween. Vacuum is applied to the platen, and air around article and between films is withdrawn through the channels defined by the dimples and thence through the apertures covered by the second film, whereupon atmospheric pressure acting on the top of the second film forces the second film into full contact with the first film around the article to make a completely sealed air tight package for the said article.
An automatic vacuum packaging apparatus which is defined by a closable frame having upper and lower sections, the lower section including a heatable platen configured with one of several patterns of transversing channels through which air can be evacuated through two separate conduits drawn into one vacuum chamber located beneath the lower platen. The upper section is closable over the lower section and has a separate variable heating element and separate peripheral attachment to the vacuum. Plastic sheets may be placed on the upper and lower frames, and an object placed between them. Then, through the electronically controlled interaction of the vacuum, heating elements, channels and closure of the frames the object may be vacuum sealed between the plastic sheets. The patterns of channels allow for the improved removal of air as the channels vary in length thus increasing the ability of the vacuum to efficiently remove over 97% of the air by concentrating the pull of the vacuum in smaller areas.
A method for the vacuum packaging of articles including at least the steps of: creating a plurality of recesses in a backing board; positioning at least one article on said backing board; placing a film substantially over said at least one article; and using a vacuum packaging machine to substantially package said at least one article, said at least one article being situated between the backing board and the film, wherein the thickness of the backing board is at least 2 mm. Also a packaged article, the article being packaged between a backing board and a film, wherein the backing board has a thickness of at least 2 mm and the backing board further has a plurality of recesses therein.
This invention relates to a method and apparatus for the automatic assembly of a flexible interlayer sheet with one or more bent glass sheets using residual heat from bending the glass sheets to make the flexible interlayer sheet sufficiently tacky to avoid relative sliding between the sheets comprising the subassembly or sandwich that is assembled.
This invention relates to an arrangement of vacuum cups in a bent glass sheet sandwich assembly apparatus and a method of using said arrangement that provides a temporary bias to the central portion of a bent glass sheet to insure that a flexible sheet of interlayer material applied to the bent glass sheet initially engages its central portion and the area of engagement extends gradually to the edge of the sheets to avoid entrapment of air or other vapors in the interface of the resulting subassembly. When another bent glass sheet is applied to the opposite surface of the flexible sheet of interlayer material, the subassembly is temporarily biased once more to insure initial engagement in the central portion gradually extending to the edge of the sheets to avoid entrapment of air or other vapors in the interface of the subassembly with the second bent glass sheet.
Assembly apparatus including a vacuum mold for supporting a flexible sheet of interlayer material for assembly against a bent glass sheet or between a pair of bent glass sheets of matching configuration has a first apertured wall shaped to conform to the shape of the bent glass, and a second apertured wall of conforming shape adapted for coupling to a vacuum source to form and hold the flexible sheet of interlayer material against the mold in unwrinkled condition. The mold is pivoted to a carriage from a mold loading orientation of convex elevational configuration to a mold unloading orientation of concave elevational configuration. Carriage movement between a mold loading station and an assembly station is correlated to the elevational configuration of the mold in assembling said flexible sheet of interlayer material against one or more bent glass sheets.
