Application of Zipper Lengths to a Web

Abstract

The apparatus comprises a rotary turret 18 having circumferentially spaced grooves 30 a , 30 b , 30 c for receiving pre-cut lengths of zipper 58 consisting of first and second interengageable profile strips. Sliders 46 for engaging and re-engaging the profiles are mounted on the zipper lengths by a rotary slider applicator 42 . A web 12 of plastics material is fed beneath the turret 18 and receives the zipper lengths which are secured to the web by a heated sealing bar 60 . The web with zippers attached is fed to a form-fill-seal machine 20 on which the web is formed into individual bags which are filled and separated from one another.

1 . An apparatus for applying pre-cut lengths of zipper transversely to a moving web of material at intervals spaced in the direction of movement of the web, comprising: 
 means for advancing a web of material in a predetermined direction;    a turret having a surface containing a plurality of circumferentially-spaced axially-extending grooves for receiving pre-cut lengths of zipper;    means for driving the turret to rotate about the axis of the cylinder;    the turret being positioned relative to the web so that its axis of rotation extends transversely to the direction of advancement of the web and, upon rotation of the turret, the grooves in its surface are brought successively to a location in which pre-cut zipper lengths occupying the grooves are presented for attachment to the web;    means for feeding pre-cut lengths of zipper comprising first and second interengageable profiles and a slider mounted thereon successively to the grooves of the turret at a loading location different from the attachment location;    means for causing removal of pre-cut zipper lengths from the grooves of the turret at the attachment location and for attachment of the zipper lengths to the web; and    means for mounting sliders on the zipper so each length of zipper fed to the turret has a slider mounted thereon.    
   
   
       2 . An apparatus according to  claim 1 , to which the means for mounting the sliders on the zipper comprise a rotary zipper applicator.  
   
   
       3 . An apparatus according to  claim 2 , in which a knife is located between the slider applicator and the feeding location for cutting a continuous supply of zipper into the pre-cut lengths.  
   
   
       4 . An apparatus according to  claim 1 , in which each groove in the turret includes a wider portion for receiving the slider on each pre-cut zipper length.  
   
   
       5 . An apparatus according to  claim 4 , in which each wider portion extends to slightly beyond the mid-point of its respective groove from an insertion end thereof.  
   
   
       6 . An apparatus according to  claim 1 , in which the means for removal and attachment of the zipper lengths comprises a heated sealing bar which is movable towards and away from the film and is located adjacent the attachment location at the opposite side of the film to the turret.  
   
   
       7 . An apparatus according to  claim 1 , in which the slider-mounting means produces zipper having its profiles disengaged from each other and the apparatus includes, between the slider-mounting means and the turret, a device for engaging the zipper profiles with each other, the device comprising a pair of rollers through the nip of which the zipper passes and which are arranged to engage the profiles of the zipper with each other and to separate from each other to allow the sliders to pass therebetween.  
   
   
       8 . An apparatus according to  claim 7 , in which the roller surfaces forming the nip are convex.  
   
   
       9 . An apparatus according to  claim 1 , including a form-fill-seal machine arranged to receive the web with zippers attached and to form the web into bags and to fill the bags with a product, the zipper lengths forming reclosable fasteners of the bags.  
   
   
       10 . An apparatus according to  claim 1 , including a machine arranged to receive the web with zippers attached and to form the web into bags for subsequent filling with a product, the zipper lengths forming reclosable fasteners of the bags.  
   
   
       11 . An apparatus according to  claim 1 , including a means for forming the web with zippers attached into a roll for subsequent use in making empty bags or in a form-fill-seal machine.  
   
   
       12 . A device for engaging the profiles of a slider zipper, the device a pair of rollers through the nip of which the zipper passes and which are arranged to engage the profiles of the zipper with each other and to separate from each other to allow the sliders to pass therebetween.  
   
   
       13 . A device according to  claim 12 , in which the roller surfaces forming the nip are convex.  
   
   
       14 . A method of applying pre-cut lengths of zipper transversely to a moving web of material at intervals spaced in the direction of movement of the web, comprising 
 providing a web of material;    advancing the web in a predetermined direction past a rotary turret positioned to rotate about an axis transverse to the predetermined direction and having a surface containing a plurality of circumferentially-spaced axially-extending grooves for receiving pre-cut lengths of zipper;    the turret being positioned relative to the web so that, upon rotation, the zipper-receiving grooves thereof are brought successively to a zipper-application location in which zipper lengths occupying the grooves are presented for application to the web in directions extending transversely thereof;    feeding pre-cut lengths of zipper to successive zipper-receiving grooves of the rotary turret at a location different from the zipper-application location, each zipper length comprising first and second interengageable profiles and a slider mounted thereon;    rotating the turret to advance the zipper lengths successively from the receiving location to the application location; and    attaching the zipper length to the web at the zipper-application location.    
   
   
       15 . A method according to  claim 14 , in which the zipper lengths are attached to the web by means of a heated sealing bar which is movable towards and away from the film and is located adjacent the attachment location at the opposite side of the film to the turret.  
   
   
       16 . A method according to  claim 14 , in which the sliders are mounted on the zipper lengths by means of a rotary zipper applicator.  
   
   
       17 . A method according to  claim 14 , in which the sliders are mounted on a continuous length of zipper which is subsequently cut into lengths.  
   
   
       18 . A method according to  claim 14 , in which the zipper profiles are disengaged during mounting of the sliders thereon and are re-engaged prior to feeding to the turret, re-engagement being by passing the zipper between the nip of a pair of rollers which are arranged to separate from each other to allow the sliders to pass therebetween.  
   
   
       19 . A method according to  claim 14 , including the further step of feeding the web with zippers attached to a form-fill-seal machine arranged to receive the web with zippers attached and to form the web into bags and to fill the bags with a product the zipper lengths forming reclosable fasteners of the bags.  
   
   
       20 . A method according to  claim 14 , including the further step of feeding the web with zippers attached to a machine for forming the web into bags for subsequent fitting with a product, the zipper lengths forming reclosable fasteners of the bags.  
   
   
       21 . A method according to  claim 14 , including the further step of forming the web with zippers attached into a roll for subsequent use in making empty bags or in a form-fill-seal machine.  
   
   
       22 - 23 . (canceled)