Apparatus and process for packaging a product
An apparatus for packaging a product comprises a packaging assembly to fix a film sheet to a support. The packaging assembly includes a lower tool having seats for receiving the support and an upper tool facing the lower tool and comprising a film holding plate for holding the film sheet. The film holding plate has an active surface for receiving the film sheet, where the upper and lower tools cooperating to define a packaging chamber. The packaging assembly is open to receive the film sheet in a first operating condition and is hermetically closed in a second operating condition. The film holding plate has a lateral surface extending substantially perpendicular to a plane defined by the active surface, the film holding plate comprising ejectors arranged in the lateral surface for ejecting a stream of gas substantially parallel to said plane and substantially away from a center of the active surface.
1. A process of packaging a product arranged on a support, said support having a base wall and a side wall, the process comprising:
unrolling a film from a roll,
transversely cutting an unrolled portion of film and preparing a cut film sheet,
moving the cut film sheet into a packaging chamber of a packaging assembly and into proximity of a film holder arranged within the packaging chamber, the film holder having an active surface,
activating ejection of a plurality of streams of gas around a perimeter of the film holder, the plurality of streams of gas being ejected over a peripheral portion of the cut film sheet in a direction substantially parallel to a plane defined by the cut film sheet and away from a center of the cut film sheet, in order to position or maintain the peripheral portion substantially within the plane of the cut film sheet,
moving a support into the packaging chamber and below the film holder, substantially in superimposition with the cut film sheet,
moving the support into a position substantially in contact with the cut film sheet,
deactivating the ejection of the plurality of streams of gas, and
heat sealing the film sheet to the support.
2. The process according to claim 1 , further comprising:
after moving the support into the packaging chamber, hermetically closing the packaging chamber with the cut film sheet held above the support, and
after heat sealing the film sheet to the support, opening the hermetically closed packaging chamber and moving the support having the cut film sheet sealedly fixed thereto out of the packaging chamber.
3. The process according to claim 1 , wherein the cutting of the film into film sheets takes place outside the packaging chamber at a station remote from a location where the film sheets are coupled to the support, and
wherein the support comprises and horizontal rim radially emerging from said side wall.
4. The process according to claim 1 , further comprising at least one of:
evacuating the hermetically closed packaging chamber;
injecting a stream of controlled gas configured to create a modified atmosphere within the chamber; or
evacuating the hermetically closed packaging chamber until a pressure is in a range between 100 and 300 mbar and then, while the film sheet is kept at a distance from a support mouth, injecting a stream of controlled gas into the packaging chamber, the stream of controlled gas being configured to create a modified atmosphere.
5. The process according to claim 1 , further comprising heating the film sheet, wherein heating the film sheet comprises at least one of:
uniformly heating the film sheet, wherein the film sheet is not heat shrinkable;
heating a peripheral portion of the film sheet, wherein the film is heat shrinkable; or
heating a peripheral portion of the film sheet to a first temperature adequate for heat sealing and heating a central portion of the film sheet to a second temperature adequate for rendering the film sheet deformable.