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Successive pouches are formed from a web of plastic film by advancing the web through a folding station and folding the web along a longitudinal fold line to form a two-ply portion and a single ply portion adjacent thereto. At a sealing station, confronting surfaces of the two-ply folded portion of

Successive pouches are formed from a web of plastic film by advancing the web through a folding station and folding the web along a longitudinal fold line to form a two-ply portion and a single ply portion adjacent thereto. At a sealing station, confronting surfaces of the two-ply folded portion of the web are sealed together along longitudinally spaced apart seal areas extending transversely across the two-ply portion to define a series of successive pouches interconnected by the seal areas. At a flap forming station predetermined waste areas are severed and removed from the single ply portion of the web to form the same into a series of successive flaps extending alongside each of the pouches and adapted for being folded over the pouches to close the same. The predetermined waste areas are quickly severed and removed by first piercing the single ply web at a predetermined point spaced from the free longitudinal edge thereof and corresponding to one end of the waste area, and then severing the single ply portion from the point of piercing along two spaced apart cut lines extending to the free longitudinal edge thereof. The waste area is graspingly engaged closely adjacent to the free longitudinal edge during severing to facilitate severing the waste area free from the remaining web, and is thereafter ejected clear of the advancing web by a blast of air. After heat sealing and flap formation, the web is advanced to a cut-off station and successively severed transversely across the folded web and across a medial portion of each seal area to separate the interconnected pouches from one another.

대표청구항 ▼

A method of forming successive pouches from a web of plastic film comprising advancing the web of plastic film from a supply source to a folding station and folding the web along a longitudinal fold line so as to position one free longitudinal edge of the web between the fold line and the other free

A method of forming successive pouches from a web of plastic film comprising advancing the web of plastic film from a supply source to a folding station and folding the web along a longitudinal fold line so as to position one free longitudinal edge of the web between the fold line and the other free longitudinal edge of the web to thereby define a two-ply portion between the fold line and said one free longitudinal edge of the web and a single ply portion adjacent thereto between the said one free longitudinal edge of the web and said other free longitudinal edge, advancing the folded web from the folding station to a sealing station and sealing together confronting surfaces of the two-ply portion along longitudinally spaced apart seal areas extending transversely across the two-ply portion to thereby define in the two-ply portion of the folded web a series of successive pouches interconnected by the seal areas, advancing the thus sealed folded web from the sealing station to a flap forming station and successively severing and removing from the single ply portion of the web, in areas adjacent to and in transverse alignment with each of the seal areas, longitudinally spaced transversely extending waste areas to thereby form the single ply portion into a series of successive flaps extending alongside each of the succesive pouches and adapted for being folded over the pouches to close the same, each successive severing and removing operation comprising the steps of supporting the single ply portion of the web surrounding the waste area to be removed while piercing the web at a predetermined point spaced from the free longitudinal edge oF the single ply portion and corresponding to one end of the waste area, thereafter severing the single ply portion from the point of piercing along two spaced apart cut lines extending generally transversely across the single ply portion toward the free longitudinal edge while grasping the single ply portion of the web in said waste area and closely adjacent to said free longitudinal edge, maintaining grasping the web while continuing severing along the two transversely extending cut lines and on opposite sides of the point of grasping and to and through the free longitudinal edge of the web to thereby cut the waste area free from the remaining web, and releasing the cut-out waste area and ejecting the same clear of the advancing web, and advancing the thus formed series of interconnected pouches from the flap forming station to a cut-off station and successively cutting transversely across the folded web and across a medial portion of each seal area to thereby separate the interconnected pouches from one another. Apparatus for forming successive pouches from a web of plastic film comprising a folding station including means for receiving a web of plastic film from a supply source and folding the web along a longitudinal fold line so as to position one free longitudinal edge of the web between the fold line and the other free longitudinal edge of the web to thereby form a two-ply portion between the fold line and said one free longitudinal edge of the web and a single ply portion adjacent thereto between said one free longitudinal edge of the web and the other free longitudinal edge, means for advancing the web through the folding station and forwardly therefrom along a predetermined path, a sealing station positioned forwardly of the folding station and including means for sealing confronting surfaces of the two-ply portion of the web together along longitudinally spaced apart seal areas extending transverSely across the two-ply portion to thereby define a series of successive pouches interconnected by the seal areas as the folded web is advanced through the sealing station, a flap forming station positioned forwardly of the folding station and including means for successively severing and removing from the single ply portion, as the folded web is advanced through the flap forming station, longitudinally spaced transversely extending waste areas of predetermined shape to thereby form the single ply portion into a series of successive flaps adapted for being folded over the pouches formed in the two-ply portion, said severing and removing means including means for supporting the single ply portion of the web surrounding the predetermined shaped waste area to be removed, a reciprocating cutter blade having one end thereof sharpened and positioned for piercing the single ply portion of the web at a predetermined point spaced from the free longitudinal edge of the single ply portion and corresponding to one end of the waste area to be removed and having a pair of spaced apart sharpened cutting edges extending from said one sharpened end and being inclined at an angle to the plane of the web for thereafter severing the single ply portion from the point of piercing along two spaced apart cut lines extending generally transversely across the single ply portion to the free longitudinal edge thereof, means operating in timed relation with said cutter blade for grasping the single ply portion of the web in said waste area closely adjacent the free longitudinal edge during severing of the waste area along said cut lines, and for releasing the cut-out waste area upon completion of severing thereof from the remaining web, and means operating in timed relation with said cutter blade for ejecting the cut-out waste area clear of the advancing web after the piercing and severing operation is completed, and a cut-off station located forwardly of the sealing station and the flap forming station and including means for successively cutting transversely across the folded web and across a medial portion of each seal area to thereby separate the interconnected pouches from one another.