Method for producing a side-gusseted bag and flat, unfilled side-gusseted bag

Abstract

A longitudinal method for producing a side-gusseted bag includes providing an incision extending in a transverse direction in a bag film for each side-gusseted bag in such a way that, in the case of a subsequently formed side-gusseted tube, the incision extends over both side gussets and a first front wall that is situated between the side gussets. Proceeding from the incision, the first front wall, together with the corresponding parts of the side gussets, is folded back, on which a separate film section is placed and fastened in the folded-open region. The folded-over section is folded back in such a way that all connecting seams of the separate film section extend in parallel to each other in the transverse direction.

What is claimed is: 
     
         1 . A method for producing a side-gusseted bag, comprising the steps of:
 supplying a material web of a bag film supplied in a production direction (p);   folding the bag film to yield a side-gusseted tube comprising a first front wall, a second front wall and side gussets, which are disposed between and connect the first and the second front walls; and   individual side-gusseted bags separated from the side-gusseted tube ( 14 );   wherein an incision extending in a transverse direction is produced in the bag film for each side-gusseted bag such that, in the side-gusseted tube, the incision extends over both side gussets and the first front wall, which is situated between the side gussets;   wherein in the side-gusseted tube, the first front wall, which is parted by the incision, is lifted on one side of the incision and is at least partially folded over, whereby sections of the underlying second front wall and the side gussets are exposed;   wherein to form a flat base, a separate film section is connected via first connecting seams to the folded-over section of the first front wall and the second front wall and via second connecting seams to the exposed side gussets, and   wherein the folded-over section is folded back in such a way that the second connecting seams extend in parallel to the first connecting seams in the transverse direction.   
     
     
         2 . The method according to  claim 1 , further comprising trimming edges of the separate film section, and the lower edges of the front walls and side gussets, during the separation of individual side-gusseted bags from the side-gusseted tube. 
     
     
         3 . The method according to  claim 2 , further comprising implementing a double cut along two cutting lines extending in the transverse direction to trim and separate the individual side-gusseted bags. 
     
     
         4 . The method according to  claim 1 , further comprising arranging reclosure strips extending transversely to the production direction (p) on the material web with uniform spacing, such that after the formation of the side-gusseted tube, the reclosure strips extend on one of the side gussets and over a portion of each of the two front walls. 
     
     
         5 . The method according to  claim 4 , further comprising providing the side gusset positioned opposite the reclosure strip, in a case of the side-gusseted tube, with handles. 
     
     
         6 . The method according to  claim 1 , further comprising closing the side-gusseted tube closed around a circumference by use of a heat-sealed seam. 
     
     
         7 . The method according to  claim 1 , further comprising fastening the separate film section to the front walls and the side gussets using heat-sealed seams. 
     
     
         8 . A flat, unfilled side-gusseted bag, comprising
 two front walls positioned opposite each other,   a first side gusset and a second side gusset, wherein the first and the second side gussets are positioned opposite each other, extend along a bag longitudinal direction (l), and connect the two front walls to each other   a film section provided in a form of a flat base, wherein the film section is connected via first heat-sealed seams to lower ends of the front walls and via second heat-sealed seams to lower ends of the side gussets;   wherein the film section is situated between the front walls in such a way that the first heat-sealed seams and the second heat-sealed seams are arranged in parallel to each other along a bag transverse direction (q).   
     
     
         9 . The flat, unfilled side-gusseted bag according to  claim 8 , wherein the front walls and the side gussets are formed from a bag film. 
     
     
         10 . The flat, unfilled side-gusseted bag according to  claim 8 , wherein at least one reclosure device comprising a reclosure strip is provided in a region of the first side gusset that extends along the bag transverse direction (q) across only a portion of a width of the front walls and allows the first side gusset to be folded outward to form a reclosable spout. 
     
     
         11 . The flat, unfilled side-gusseted bag according to  claim 10 , characterized in that an upper bag edge is closed above the reclosure device by a top sealing seam. 
     
     
         12 . The flat, unfilled side-gusseted bag according to  claim 11 , wherein the side gussets extend from the flat base up to the top sealing seam on the upper bag edge.