Laser Cutoff Stacker Assembly

Abstract

The present invention contemplates a machine and method for performing the laser sealing and laser cutting of flexible material into segments, such as a polymeric web in which the segments will ultimately be individual bags. The machine includes a generally cylindrical drum having openings on an exterior surface. A laser produces a laser beam that contacts the flexible material while the flexible material is being held on the drum. The drum is preferably comprised of drum sections that can be independently moved in the radial direction. The machine includes a cam system causing the drum sections to be sequentially moved in the radial direction. Typically, this radial movement is for the purpose of releasing the individual segments of the flexible material that have been cut by the laser.

1 . A method for cutting flexible material, comprising:
 advancing said flexible material toward a rotatable drum having a periphery defined by a plurality of drum sections;   engaging said rotatable drum with said flexible material;   holding said flexible material against said rotatable drum while said rotatable drum is rotating;   cutting said flexible material into segments with a laser beam projecting from an interior of said rotatable drum through slots at least partially defined by said plurality of drum sections; and   sequentially engaging each of said plurality of drum sections with a cam to sequentially move each of said plurality of drum sections away from said periphery to a collection station for collecting said segments.   
     
     
         2 . The method of  claim 1 , wherein said flexible material is a web of polymeric material. 
     
     
         3 . The method of  claim 2 , wherein said segments are individual packages. 
     
     
         4 . The method of  claim 1 , wherein said step of holding includes suctioning said flexible material against said circumferential drum sections. 
     
     
         5 . The method of  claim 1 , wherein each of said plurality of circumferential drum sections rotates around said cam and includes a linkage with a cam follower, said step of sequential engaging includes engaging said cam with said cam followers. 
     
     
         6 . The method of  claim 5 , wherein said cam remains stationary. 
     
     
         7 . The method of  claim 1 , wherein said sequentially engaging includes allowing each of said plurality of circumferential drum sections to move to a motionless dwell point. 
     
     
         8 . The method of  claim 7 , wherein said motionless dwell point is adjacent to said collection station. 
     
     
         9 . The method of  claim 8 , further including releasing said segment into said bag collection station while at said motionless dwell point. 
     
     
         10 . The method of cutting flexible material into segments, comprising:
 holding said flexible material against a rotatable drum comprising a plurality of drum sections;   cyclically moving said drum sections around a generally circular locus;   cutting said flexible material into said segments with a laser beam;   moving each of said drum sections outside said locus; and   releasing each of said segments from said drum sections to a collection station while said drum sections are located outside said locus.   
     
     
         11 . The method of  claim 10 , wherein said moving includes engaging each of said drum sections with a cam. 
     
     
         12 . The method of  claim 11 , wherein said cam is stationary and each of said drum sections includes a cam follower for engaging said cam. 
     
     
         13 . The method of  claim 12 , wherein said moving includes passing said drum sections through a dwell point wherein said drum sections remain momentarily motionless. 
     
     
         14 . The method of  claim 13 , wherein said releasing occurs at said dwell point. 
     
     
         15 . The method of  claim 10 , wherein said polymeric material is a web of material. 
     
     
         16 . The method of  claim 15 , wherein said segments are bags created from said web of material. 
     
     
         17 . The method of  claim 10 , wherein said holding includes suctioning said flexible material against said drum sections. 
     
     
         18 . The method of  claim 17 , wherein said drum sections include openings for suctioning said flexible material. 
     
     
         19 . The method of  claim 10 , wherein said releasing includes stacking said segments in said collection station. 
     
     
         20 - 35 . (canceled)