Skin Packaging Machine

Abstract

A skin packaging machine in which a first continuous film and a second continuous and thermoplastic film above the first film are supplied in a forward direction of the machine. The machine includes a sealing station configured for receiving both films, and it comprises an upper tool pressing on the films to seal them to one another, with a closed holding contour delimiting the area of said films being sealed. The sealing station further comprises a sealing gasket attached to the holding contour, the sealing gasket having, on each side with respect to the forward direction, an operation zone with a notched configuration which is facing the space delimited by said sealing gasket.

What is claimed is: 
     
         1 . A sealing station configured to receive a first film and a second film disposed above the first film, the sealing station having a rearward entrance side and a forward exit side and configured to seal the second film to the first film, the sealing station comprising:
 a lower tool that is configured to support the first film; and   an upper tool positioned above the lower tool, in a first arrangement the upper and lower tools are in contact with one another, in a second arrangement the upper and lower tools are not in contact with one another, the upper tool including a heating surface and a gasket that is configured to urge the second film against the first film when the upper and lower tools are in the second arrangement, the gasket having a first side with a first operation zone, the first operation zone including notches that are separated by trenches, the notches facing inward into a space delimited by the gasket, the heating surface having a plurality of suction holes that are configured to draw the second film towards the heating surface when a suction is applied through the suction holes, the notches and trenches of the first operation zone being configured to cause the second film to be deformed inside the trenches in a tensed state to inhibit or reduce the formation of creases in the second film when the second film is drawn toward the heating surface.   
     
     
         2 . The sealing station according to  claim 1 , wherein the notches of the first operation zone are configured to limit the deformation of the second film in the trenches in a manner that postpones a contact of the second film with the heating surface when the second film is drawn towards the heating surface. 
     
     
         3 . The sealing station according to  claim 1 , wherein the gasket comprises a second side opposite the first side, the first and second sides of the gasket extending lengthwise in a direction transverse to the rearward entrance side and forward exit side of the sealing station, the second side the gasket having a second operation zone, the second operation zone including notches that are separated by trenches, the notches facing inward into the space delimited by the gasket, the notches and trenches of the second operation zone being configured to cause the second film to be deformed inside the trenches in a tensed state to inhibit the formation of creases in the second film when the second film is drawn toward the heating surface. 
     
     
         4 . The sealing station according to  claim 3 , wherein the notches of the second operation zone are configured to limit the deformation of the second film in the trenches in a manner that postpones a contact of the second film with the heating surface when the second film is drawn towards the heating surface. 
     
     
         5 . The sealing station according to  claim 1 , wherein the trenches of the first operation zone have a same first width and the notches of the first operation zone have a same second width, the second width being greater than the first width. 
     
     
         6 . The sealing station according to  claim 3 , wherein the trenches of the first and second operation zones have a same first width and the notches of the first and second operation zones have a same second width, the second width being greater than the first width. 
     
     
         7 . The sealing station according to  claim 1 , wherein the gasket has a first width outside the first operation zone, the notches of the first operation zone have a second width that is substantially the same as the first width. 
     
     
         8 . The sealing station according to  claim 3 , wherein the gasket has a first width outside the first and second operation zones, the notches of the first and second operation zones have a second width that is substantially the same as the first width. 
     
     
         9 . The sealing station according to  claim 1 , wherein the gasket has a thickness that is substantially uniform around an entire perimeter of the gasket. 
     
     
         10 . The sealing station according to  claim 1 , wherein the trenches of the first operation zone have a same length and the notches of the first operation zone have a same second length. 
     
     
         11 . The sealing station according to  claim 3 , wherein the trenches of the first and second operation zones have a same length and the notches of the first and second operation zones have a same second length. 
     
     
         11 . The sealing station according to  claim 1 , wherein the first side of the gasket is disposed transverse to at least one of the rearward entrance side and forward exit side of the sealing station, the first side having a first length, the first operation zone extending less than the entire first length. 
     
     
         12 . The sealing station according to  claim 3 , wherein the first and second sides of the gasket are each disposed transverse to at least one of the rearward entrance side and forward exit side of the sealing station, the first side having a first length, the first operation zone extending less than the entire first length, the second side having a second length, the first operation zone extending less than the entire second length. 
     
     
         13 . The sealing station according to  claim 1 , wherein first operation zone is located nearer the rearward entrance side of the sealing station than to the forward exit side of the sealing station. 
     
     
         14 . The sealing station according to  claim 3 , wherein the first and second sides of the gasket are arranged substantially parallel to one another with each of the first and second operation zones being located nearer the rearward entrance side of the sealing station than to the forward exit side of the sealing station. 
     
     
         15 . A packaging machine comprising:
 a first feeding station for supplying a first film in a forward direction of the packaging machine;   a second feeding station for supplying a second film in the forward direction and above the first film; and   a sealing station that includes a lower tool and an upper tool, the lower tool being configured to support the first film, in a first arrangement the upper and lower tools are in contact with one another, in a second arrangement the upper and lower tools are not in contact with one another, the upper tool including a heating surface and a gasket that is configured to urge the second film against the first film when the upper and lower tools are in the second arrangement, the gasket having a side with an operation zone, the operation zone including notches that are separated by trenches, the notches facing inward into a space delimited by the gasket, the heating surface having a plurality of suction holes that are configured to draw the second film towards the heating surface when a suction is applied through the suction holes, the notches and trenches of the first operation zone being configured to cause the second film to be deformed inside the trenches in a tensed state to inhibit or reduce the formation of creases in the second film when the second film is drawn toward and heated by the heating surface.   
     
     
         16 . The packaging machine according to  claim 15 , further comprising a pre-heating station located upstream from the sealing station in the forward direction for pre-heating the second film before being supplied to the sealing station, the sealing station having a rearward entrance side and a forward exit side, the operation zone being located nearer the rearward entrance side of the sealing station than to the forward exit side of the sealing station. 
     
     
         17 . The packaging machine according to  claim 15 , wherein the first feeding station includes a cutting station upstream from the sealing station in the forward direction, the cutting station having a cutting tool that is suitable for generating at least one opening in the first film, the sealing station comprising vacuum means for applying a vacuum between the first and second films through the at least one opening during the sealing of the first and second films, the cutting tool being configured so that, or arranged in the packaging machine such that the at least one opening made in the first film coincides with a trench of the operation zone of the gasket during the sealing of the first and second films. 
     
     
         18 . The packaging machine according to  claim 17 , wherein the cutting tool is configured for making an opening for each of the trenches of the operation zone of the gasket. 
     
     
         19 . The packaging machine according to  claim 17 , wherein the sealing station comprises at least one additional element arranged in the lower tool that is configured for being introduced through the at least one opening made by the cutting tool in the first film. 
     
     
         20 . The packaging machine according to any of  claim 15 , wherein the first feeding station comprises a feeder supplying the first film and a forming station downstream from the feeder in the forward direction, the forming station being configured for sequentially generate a plurality of cavities in the first film in the forward direction, the packaging machine comprising a separating station arranged downstream the sealing station in the forward direction and configured for cutting the first and second films to generate individual packages comprising a tray with a corresponding cavity and a flap around the cavity, the forming station being configured to form the cavity such that a width on the sides of the first film extending from a lateral end of the cavity to an end of the first film is left unformed, the sealing station being configured so that the gasket is supported on the first and second films beyond the flap, towards an outer side of the first and second films during the sealing of the first and second films.