Bag making apparatus and method

Claim 1

An elongate bag-making apparatus for automatically producing a plurality of hangered plastic bags, said apparatus comprising (a) a horizontal frame having opposed ends and opposed elongate sides, (b) means for dispensing a continuous elongate web of thermoplastic film in folded multi-ply relationship adjacent one end of said frame for generally horizontal movement of said web over said frame to the other end thereof, said web including a narrow elongate flap ply formed by folding said film upwardly along a fold line forming one elongate side edge of said web adjacent one side of said frame and inwardly towards the center area of said web, whereby the opening beneath said flap ply faces the center area of said web, (c) a carriage element, (d) elongate track means including an elongate side rail of said frame for supporting said carriage element over the center area of said web for adjustable positioning along a portion of the length thereof, (e) a plurality of workstations mounted on said carriage element in predetermined spaced relation to each other and to said elongated flap ply along the length of said web for simultaneously applying a plurality of physical bag features thereto, said workstations comprising (i) a slitting means comprising a slitting blade extendable from the center area of said web outwardly beneath said flap ply to form a succession of evenly-spaced narrow slits in said fold line, along the length thereof, and (ii) a hanger supplying and insertion means spaced beyond said slitting means and comprising a means for supplying a succession of flat hangers, each having a narrow central hook portion and an elongate retainer bar portion, to a position above and adjacent the center area of said web, and a means for pushing outwardly against the retainer bar portion of each said hanger to slide each hanger horizontally outwardly, beneath said flap ply, to insert the hook portion thereof through a said slit in said fold line and to engage the bar portion thereof with said fold line, said apparatus also comprising (f) a means spaced beyond said hanger supplying and insertion means for heat-sealing said flap ply to the underlying film ply along a narow line inwardly from the bar portions of each hanger, to confine each inserted hanger within said flap ply with the hook portions extending outwardly through each said narrow slit, (g) a cutting means adjacent the other end of said frame for forming a plurality of uniformly-spaced, heat fused transverse cuts which segregate said web into a plurallity of uniform, hangered plastic bags, and (h) a means for pulling said elongate web from said dispensing means to said cutting means, the adjustable positioning of said carriage element permitting said element to be repositioned along the length of the web, relative to the location of the cutting station, in order to simultaneously adjust the distance between each of the workstations mounted on the carriage element and said cutting means and thereby center the location of each said hanger relative to the flap ply on each said uniform hangered plastic bag.