Carton having stacking strength-enhancing feature

Abstract

A carton has a triangular shaped internal buttress arrangement for enhancing the stacking strength of the carton. The arrangment is formed from the distal portion of at least one of the side end flaps.

1 . A carton comprising: 
 top and bottom opposed walls hingedly interconnected by a pair of side walls to form a tubular body having an interior;    at least one article received in said tubular body;    an end closure structure for at least partially closing each of opposite ends of said tubular body;    a buttress arrangement provided at least in part by each said end closure structures to enhance the stacking strength of the carton, each of said buttress arrangements including at least one tubular column of a generally triangular cross section, said at least one tubular column being disposed next to said at least one article such that a portion of said at least one tubular column is pressed against one of said side walls and thereby said at least one tubular column is held in an erected tubular form.    
   
   
       2 . The carton of  claim 1  wherein said each end closure structure comprises a pair of side end flaps joined to said side walls respectively, each of said side end flaps comprising a proximal portion hingedly connected to a respective one of said side walls and extending toward the other side wall, one of said side end flaps further comprising a distal portion of hingedly connected to said proximal portion of said one side end flap, said distal portion of said one side end flap extending into said interior to form a respective one of said buttress arrangements.  
   
   
       3 . The carton of  claim 2  wherein said distal portion of said one side end flap extends all the way between said top and bottom walls to be in abutment at upper and lower ends thereof on said top and bottom walls.  
   
   
       4 . The carton of  claim 1  wherein said buttress arrangement at said one end of side tubular body is removable from said carton along with a removable portion to permit said articles to be dispensed from said carton.  
   
   
       5 . The carton of  claim 3  wherein said each side end flap includes a vertical fold line dividing said each end flap into said distal and proximal portions, said distal portion having a horizontal transverse size greater than a horizontal transverse size of said proximal portion.  
   
   
       6 . A carton comprising: 
 top and bottom opposed walls hingedly interconnected by a pair of side walls to form a tubular body having an interior;    an end closure structure for at least partially closing each of opposite ends of said tubular body; and    a buttress arrangement provided by each of said end closure structures, each of said buttress arrangements being disposed within said interior and extending vertically between said top and bottom walls to enhance the stacking strength of said carton,    wherein said each end closure structure comprises a pair of side end flaps joined to said side walls respectively, each of said side end flaps of said each end closure structure comprising a proximal portion hingedly connected to a respective one of said side walls, and a distal portion hingedly connected to said proximal portion, said proximal portions extending from said side walls toward each other, said distal portions extending from said proximal portions into said interior and contacting a side wall to form a triangular buttress arrangements, wherein the triangular buttress arrangement is maintained by pressure from the contents of the carton, and    wherein said each side end flap includes a vertical fold line dividing said each side end flap into said distal and proximal portions, said distal portion having a horizontal transverse size greater than a horizontal transverse size of said proximal portion.    
   
   
       7 . The carton of  claim 6  wherein said respective buttress arrangement is achieved without the use of a glued joint between the end of said distal portion and said contacted side wall.  
   
   
       8 . The carton of  claim 7  wherein each of said distal portions of said respective buttress arrangement extends all the way between said top and bottom walls to be in abutment at upper and lower ends thereof on said top and bottom walls.  
   
   
       9 . A method for forming a carton for retaining a plurality of articles, said method comprising the steps of: 
 folding opposed end flaps of each said side wall with respect to the remainder of said blank to respective positions forming triangular buttress arrangements along the inside of the carton at the end and extending from top to bottom of the carton and; and    arranging a first row of articles on a first side wall of a blank for forming said carton;    arranging a second row of articles on a second side wall of said blank;    such that one or more articles lay upon the each said triangular buttress arrangement to help retain its shape; and    moving said first and second side walls toward each other such that said articles in said first row are brought into contact with said articles in said second row, whereby Upon closure of the carton the volume of the contents is sufficient to nearly fill the carton and to exert pressure on the inner walls of said triangular buttress to maintain their shape.    
   
   
       10 . The method of  claim 9  wherein said end flaps folding step comprises folding each said end flap upward along a first fold line between said each end flap and a respective one of said side walls, and folding said each end flap along a second fold line in said each end flap, said second fold line defining dividing said each end flap into a pair of proximal and distal portions such that said proximal portions of said each side wall extend upwardly from said each side wall and said distal portions of said each side wall extend inwardly from said proximal portions toward a side wall.