Packaging apparatus and method

Abstract

An automatic package wrapping apparatus of the L-scaler type. The packages to be wrapped are transported through the apparatus in a straight line one by one and in so doing pass through a film inverting head where they are surrounded by a pre-folded thermoplastic film. The film is supplied from the rear of the apparatus in a prefolded condition and is both turned inside out and redirected into a path corresponding to the path of the packages through the apparatus in the film inverting head. Also that method of wrapping packages wherein a generally U-shaped inverting head is provided, wherein a length of longitudinally pre-folded thermoplastic film is passed over and then through said head thereby turning the film inside out and redirecting its path and wherein the package to be wrapped is passed through said inverting head thereby surrounding itself with said film.

I claim:  .[. 
     
       1.  In an apparatus for wrapping packages in a thermoplastic film having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film sealing means having at least an intermittently operated transverse sealing means for sealing said folded film transversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.2. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film-sealing means having at least an intermittently operated transverse sealing means for sealing said folded film transversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   the path of said film travel to said head being substantially at right angles to the path of said package flow, and   the said head being set at an angle of about 45° to both said path of package flow and said path of film travel   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.3. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein the thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film-sealing means having at least an intermittently operated transverse sealing means for sealing said folded film transversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   the path of said film travel to said head being substantially at right angles to the path of said package flow, and   the said head being set at an angle of about 45° to both said path of package flow and said path of film travel   the film inverting head being mounted to move in a direction normal to said path of package flow whereby adjustment for packages of varying width may be accomplished merely by moving said film inverting head   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.4. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film sealing means having at least an intermittently operated transverse sealing means for sealing said folded film tranversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end and oriented substantially parallel one above the other, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.5. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film sealing means having at least an intermittently operated transverse sealing means for sealing said folded film transversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   the path of package flow including a package support means which extends through said film inverting head   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.6. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film sealing means having at least an intermittently operated transverse sealing means for sealing said folded film transversely between said folded edge and said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   the path of package flow including a package support means which extends through said film inverting head and wherein automatic means are provided for feeding packages one by one onto and across said support means through said inverting head across said transverse sealing means   whereby after a first transverse seal has been made in said length of film, the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to surround said package..].  .[.7. In an apparatus for wrapping packages in a thermoplastic film   having a film supply means wherein thermoplastic film is supplied as an elongated length folded back upon itself along a longitudinal axis to form a top and a bottom web portion overlying one another in close juxtaposition one to the other and is directed into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, and   a film sealing means having an intermittently operated sealing means for sealing said folded film both transversely between said folded edge and said free edges and longitudinally along said free edges   a film inverting head located between said film supply means and said film sealing means in the path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film   said inverting head comprising a pair of spaced arms operably associated at one end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film   whereby after a first transverse seal has been made in said length of film the passage of a package along said path of package flow through said inverting head and across said transverse sealing means draws enough film from said film supply means over and through said inverting head to   
     
     
        surround said package..]. .Iadd.8.  An in-line L-sealer for wrapping packages in a thermoplastic film comprising: means for providing an in-line path of package flow;   film supply means including a power unwind mechanism for supplying thermoplastic film as an elongated length folded back upon itself along a longitudinal axis along a path of film travel to form a top and a bottom web portion overlying one another in close juxtaposition one to the other to form a folded edge and free edges of said film and for directing said film into the apparatus along a horizontal path with the folded edge on one side and the free edges on the other, said power unwind mechanism responsive to package advance against a transverse seal in the folded film to provide film moving substantially tension-free through the apparatus;   film sealing means intermittently operable on substantially tension-free film for simultaneously making a longitudinal seal and the trailing transverse seal for the same package by sealing said folded film transversely between said folded edge and said free edges and along said free edges, said trailing transverse seal simultaneously making the leading transverse seal for the next package and severing the film transversely between the successive packages;   a film inverting head having a center line located between said film supply means and said film sealing means in said path of package flow through said apparatus in such a manner that the fold line in said folded film may be passed through the center line of the inverting head, and that the film is redirected and turned inside out in passing over and through said inverting head, said inverting head providing an opening into which a package may be inserted between the connected webs of said film;   said inverting head comprising a pair of spaced arms operably associated at one end and remaining in spaced relation past said free edges of said film at the other end, said arms intersecting said path of package flow with one arm extending above and the other extending below said path of package flow and being directed at an angle both to the path of package flow and to the path of film travel from said supply means to said head with the operably associated end of said head substantially aligned with the path of the folded edge of said film and the spaced arms at said other end of said head extending beyond the free edges of said film,   whereby after a first transverse seal has been made in said length of film, the passage of each subsequent package along said path of package flow through said inverting head engages the previously made transverse seal and further passage along said path across said transverse sealing means draws enough film from said film supply means to be delivered relatively tension-free over and through said inverting head to surround said package and provide tension-free film at said transverse sealing means at the end of said passage. .Iaddend.