Method and apparatus for making a pre-padded food bag

Abstract

There is provided a method for manufacturing pre-padded food-containing bag by perforating across a continuous web of flattened tubular thermoplastic material, forming an opening in a layer of the perforated web, separating the layers of the web, inserting an absorbent the pad through the opening into the inside of the tubular web and making a seal across the tubular web at predetermined lengths to form a bag. The result is that a continuous web of bags containing absorbent pads at discrete intervals. There is also provided an apparatus for carrying out the method.

That which is claimed:  
     
         1 . A method of making a bag from a tube of thermoplastic material comprising the steps of: 
 providing a continuous length of lay-flat seamless tubular thermoplastic web having an upper layer and a bottom layer;    perforating at least one layer of said tubular web;    forming an opening in said tubular web;    separating said tubular web sufficiently wide for an absorbent pad to be placed through said opening;    placing an absorbent pad into said opening in said tubular web;    removing excess air from the tubular material, and    converting said tubular web into a plurality of end-seal bags whereby a continuous series of bags containing said absorbent pads at discrete intervals is formed.    
     
     
         2 . The method according to  claim 1  wherein said converting comprises heat sealing across said tubular web to form a bag.  
     
     
         3 . The method according to  claim 2  wherein said continuous series of bags containing absorbent pads is wound onto a roll.  
     
     
         4 . The method according to  claim 1  further comprising adhering said absorbent pad to an inside surface of said tubular web.  
     
     
         5 . The method according to  claim 1  further comprising perforating both layers.  
     
     
         6 . The method according to  claim 1  further comprising cutting through said upper layer and perforating said bottom layer.  
     
     
         7 . The method according to  claim 1  wherein said opening in said tubular web is formed by an eccentric wheel acting against said tubular web.  
     
     
         8 . The method according to  claim 1  wherein the layers of said lay-flat tubular web are separated by blowing air into said opening.  
     
     
         9 . The method according to  claim 1  wherein said excess air is removed from said tubular web by passing the web through a pair of nip rolls to squeeze the air out of the tubular web.  
     
     
         10 . The method according to  claim 1  further comprising slitting said flat tubular web along one side thereof, inserting said absorbent pad at an angle to the direction of travel of said web, and sealing said split side of said web.  
     
     
         11 . A method of making a bag from a tube of thermoplastic material comprising the steps of: 
 providing a continuous length of lay-flat seamless tubular thermoplastic web having an upper layer and a bottom layer;    perforating at least one layer of said tubular web;    forming an opening in said tubular web;    squeezing said upper layer and said bottom layer together to close off a section of the tubular web ahead of an absorbent pad;    blowing air into said opening to separate said upper layer from said bottom layer sufficiently wide for an absorbent pad to be placed through said opening;    placing an absorbent pad into said opening in said tubular web;    removing excess air from the tubular material,    sealing said tubular web into a plurality of end-seal bags whereby a continuous series of bags containing said absorbent pads at discrete intervals is formed; and    winding said continuous series of bags containing an absorbent pad onto a roll.    
     
     
         12 . A bag machine for forming a bag having an absorbent pad therein from a roll of flattened tubular web material comprising: 
 a tubular supply section comprising 
 a holder for said roll of flattened tubular web material; and  
   a bag forming section comprising; 
 means for moving said tubular web along a predetermined path;  
 a perforator for perforating at least on layer of said tubular web;  
 a means for opening one side of said tubular web;  
 means for inserting air into said tubular web in an amount sufficient to open said tubular web enough to insert an absorbent pad;  
 means for delivering and inserting said absorbent pad into said tubular web;  
 means for removing air from said tubular web; and  
 a sealer displaced transversely across said tubular web for delimiting the length serving to form a bag, said means for delimiting the length forming a bottom seal of said bag.  
   
     
     
         13 . The bag machine for forming a bag according to  claim 12  further comprising means for winding said bags onto a roll.  
     
     
         14 . The bag machine for forming a bag according to  claim 12  wherein said sealer for delimiting said length serving to form said bag is a heat sealing wire.  
     
     
         15 . The padded bag machine for forming a bag according to  claim 13  wherein said air removal means is a pair of nip rolls through which tubular web passes.  
     
     
         16 . The bag machine for forming a bag according to  claim 12  wherein said perforator is a perforation knife set to perforate both the upper layer and the lower layer.  
     
     
         17 . The bag machine for forming a bag according to  claim 12  wherein said perforator is set to perforate one of the layers and a knife is provided to cut a slit in the other layer.  
     
     
         18 . The bag machine for forming a bag according to  claim 12  wherein said means for opening said tubular web is an eccentric wheel acting against said tubular web.  
     
     
         19 . The bag machine for forming a bag according to  claim 12  wherein said means for removing excess air from said tubular web is a pair of nip rolls to squeeze the air out of the tubular web.