ApplicationNo. 05/971997 filed on 12/21/1978
US Classes:53/432, Vacuum or gas treating426/129, Packaged product is animal flesh426/396, By covering rigid receptacle or support with flexible wrap or container53/510Vacuum or inert atmosphere
ExaminersPrimary: McGehee, Travis S.
Attorney, Agent or Firm
International ClassB65B 31/02 (20060101)
AbstractPackaging apparatus for making vacuum or gas-filled packages of the type including a flanged cup-shaped receptacle with a closure film sealed to the flanges and stretched down into the cup to engage and press against the product. The apparatus comprises a first packaging station where the film is sealed to the cup flanges part way around the cup mouth; simultaneously the film is heated in pre-selected locations to soften it for subsequent stretching. In a subsequent station, the partially-completed package is placed in a vacuum chamber and evacuated. Thereafter, a plug is driven against the still heated film, to force it down into the cup interior adjacent the product. Before or after the plug movement, the film is fully sealed to the cup, to make a hermetically-sealed package. While the plug holds the film in its stretched condition, the spaces outside of the film are vented to apply fluid pressure to the film, to cause the film to conform closely to the product shape, and to match closely the contour of the cup.