Method to accurately control size, velocity, and relative position sets of reclosable mechanism

Abstract

The apparatus includes an extrusion die and further includes a main or primary extruder for the supply of material, such as low density polyethylene, to form the tubing for the manufacture of reclosable packages, bags or pouches. The apparatus further includes at least one secondary extruder, or co-extruder, for the extruding of each reclosable profile onto the tubing. The speed of the co-extruders is controlled so as to control the extrusion of the reclosable profiles.

1 . An apparatus for producing film for reclosable packages, bags or pouches, comprising:
 a primary extruder;   at least one secondary extruder;   an extrusion die plate with a primary channel for receiving primary material from the primary extruder for forming a film;   the extrusion die plate further including at least one secondary channel for receiving secondary material from the at least one secondary extruder for forming reclosable zipper profiles on the film; and   a control device for controlling velocity of flow of the secondary material to provide desired shapes of the reclosable zipper profiles.   
     
     
         2 . The apparatus of  claim 1  wherein the at least one secondary extruder includes at least two secondary extruders. 
     
     
         3 . The apparatus of  claim 2  wherein the primary extruder provides low density polyethylene material. 
     
     
         4 . The apparatus of  claim 1  wherein the at least one secondary extruder provides resin material. 
     
     
         5 . The apparatus of  claim 2  wherein the secondary extruders include at least a first secondary extruder and a second secondary extruder, and the secondary material from the first secondary material is different from the secondary material from the second secondary extruder. 
     
     
         6 . The apparatus of  claim 2  wherein the secondary extruders include at least a first secondary extruder and a second secondary extruder, and the secondary material from the first secondary material is the same as the secondary material from the second secondary extruder. 
     
     
         7 . The apparatus of  claim 2  wherein a velocity of the film and the velocity of the secondary material are controlled so as to be equal when the secondary material and the film come into contact with each other. 
     
     
         8 . The apparatus of  claim 1  wherein at least one heated hose connects the at least one secondary extruder to the extrusion die body. 
     
     
         9 . The apparatus of  claim 2  wherein a temperature of the secondary material is controlled by the processing device. 
     
     
         10 . The apparatus of  claim 1  wherein a speed of the film is controlled whereby a circumference of the film is less than a circumference of the extrusion die plate. 
     
     
         11 . The apparatus of  claim 1  wherein the reclosable zipper profiles include a plurality of interlocking elements. 
     
     
         12 . The apparatus of  claim 1  wherein the at least one secondary extruder provides colored secondary material. 
     
     
         13 . The apparatus of  claim 1  wherein the control device controls velocity of flow of the secondary material whereby a distance between sets of profiles is controlled. 
     
     
         14 . The apparatus of  claim 1  wherein the control device controls velocity of flow of the secondary material whereby separators are provided between the interlocking elements of the reclosable zipper profiles. 
     
     
         15 . The apparatus of  claim 1  wherein the at least one secondary extruder can provide resin flows to a plurality of sets of reclosable zipper profiles. 
     
     
         16 . A zipper for reclosable packages, bags or pouches, produced by a method comprising the following steps:
 providing a primary extruder;   providing at least one secondary extruder;   providing an extrusion die plate with a primary channel for receiving primary material from the primary extruder for forming a film, further including at least one secondary channel for receiving secondary material from the at least one secondary extruder for forming reclosable zipper profiles on the film; and   providing a control device for controlling velocity of flow of the secondary material to provide desired shapes of the reclosable zipper profiles.   
     
     
         17 . The zipper of  claim 16  wherein the at least one secondary extruder includes at least two secondary extruders. 
     
     
         18 . The zipper of  claim 17  wherein the primary extruder provides low density polyethylene material. 
     
     
         19 . The zipper of  claim 16  wherein the secondary extruders provide resin material. 
     
     
         20 . The zipper of  claim 17  wherein the secondary extruders include at least a first secondary extruder and a second secondary extruder, and the secondary material from the first secondary material is different from the secondary material from the second secondary extruder. 
     
     
         21 . The zipper of  claim 17  wherein the secondary extruders include at least a first secondary extruder and a second secondary extruder, and the secondary material from the first secondary material is the same as the secondary material from the second secondary extruder. 
     
     
         22 . The zipper of  claim 17  wherein a velocity of the film and the velocity of the secondary material are controlled so as to be equal when the secondary material and the film come into contact with each other. 
     
     
         23 . The zipper of  claim 16  wherein at least one heated hose connects the at least one secondary extruder to the extrusion die body. 
     
     
         24 . The zipper of  claim 17  wherein a temperature of the secondary material is controlled by the processing device. 
     
     
         25 . The zipper of  claim 16  wherein a speed of the film is controlled whereby a circumference of the film is less than a circumference of the extrusion die plate. 
     
     
         26 . The zipper of  claim 16  wherein the reclosable zipper profiles include a plurality of interlocking elements. 
     
     
         27 . The zipper of  claim 16  wherein the at least one secondary extruder provides colored secondary material. 
     
     
         28 . The zipper of  claim 16  wherein the control device controls velocity of flow of the secondary material whereby a distance between sets of profiles is controlled. 
     
     
         29 . The zipper of  claim 16  wherein the control device controls velocity of flow of the secondary material whereby separators are provided between the interlocking elements of the reclosable zipper profiles. 
     
     
         30 . The zipper of  claim 16  wherein the at least one secondary extruder can provide resin flows to a plurality of sets of reclosable zipper profiles.