초록 ▼

A packaging machine wherein product-loaded cup-shaped receptacles are advanced with an indexing movement through a series of packaging stations. One station includes a fixed vacuum/gas chamber extending entirely over one set of receptacles. The receptacles are first evacuated through this fixed cham

A packaging machine wherein product-loaded cup-shaped receptacles are advanced with an indexing movement through a series of packaging stations. One station includes a fixed vacuum/gas chamber extending entirely over one set of receptacles. The receptacles are first evacuated through this fixed chamber, and thereafter gas is directed into the chamber to fill the receptacles. A fine wire-mesh screen is positioned between the chamber and the receptacles to constrain the air and gas flow to a vertical direction, to prevent disarrangement of the product during evacuation and gassing. A gas-curtain structure develops an enclosed region of gas above the receptacles during their movement out from under the fixed chamber over to the final sealing station. The sealing operation takes place in two successive steps within the sealing station.

대표청구항 ▼

Packaging apparatus wherein receptacles with upward-facing openings, and containing semi-liquid disarrangeable products, are moved along a line of advance passing through a series of packaging stations where packaging operations are performed, said apparatus comprising: chamber means at one of said

Packaging apparatus wherein receptacles with upward-facing openings, and containing semi-liquid disarrangeable products, are moved along a line of advance passing through a series of packaging stations where packaging operations are performed, said apparatus comprising: chamber means at one of said stations presenting a downwardly facing opening; means to support said receptacle beneath said chamber opening; said chamber means including means sealingly engageable with said support means to carry out packaging operations while in sealed communication with the receptacle; vacuum means connected to said chamber means to evacuate receptacles positioned therebeneath while sealingly engaged therewith; gas supply means connected to said chamber means and operable while a receptacle is in evacuated condition and sealingly engaged with said chamber means to deliver gas to the receptacle; control means including a screen supported beneath said chamber means for assuring that the air is evacuated from the receptacles substantially perpendicularly with respect to the upper surface of the product throughout substantially all of the areas thereof and to assure that the gas is delivered thereafter to the receptacle with the same perpendicular relationship; top film lay-down means located downstream from said chamber means and arranged to apply a cover film over a gas-filled receptacle as it is moved out of said one station, said film being disposed along a path having a downward component of motion leading towards engagement with the receptacle; second gas supply means located downstream from said chamber means and near said top film lay-down means, said second gas supply means comprising means to produce a flow of gas into the region which lies directly beneath the top film portion which is moving downwardly towards the receptacle and approaching the position where it engages the receptacle; wall means including said top film portion confining the gas supplied by said second gas supply means and thereby developing a curtain of gas overlying the gas previously placed in the receptacle by said first gas supply means to prevent displacement of that previously placed gas as the receptacle moves to the next station; said top film serving after engagement with the receptacle as the cover to hold the gas in the receptacle until said next station is reached; and sealing means at said next station operable after said cover film has been placed over the receptacle to effect a hermetic seal between said cover film and the receptacle with the gas contained therein.