Abstract: A device for sealing a preserving jaw by generation of a powerful vacuum in the head space of the jar. This is put into effect by a hood which is evacuated by means of an external vacuum pump, and is put over the jar's mouth loosely covered with a thin lid, the hood having an air tight seat on the jar. The lid is lifted by the vacuum inside of the hood and the air left within the jar is, consequently, evacuated. A special valve ensures that atmospheric air may not reenter the hood unless the lid had been pressed against the top edge of the jar's mouth, thus creating an air tight seat of both parts. The external overpressure keeps the jar tightly and durably sealed.

Abstract: This invention relates to a clamping mechanism which is effective to produce a high compressive force on the gathered open end of a thermoplastic bag containing an appropriate product, such as food items for freezing, characterized by the fact that a high compressive force is supplied to at least two spaced portions of the gathered bag end material to effect the sealing of the bag material through cold flow of the material and without the application of any external heat.