Container with locking flanges

Abstract

A carton, and a blank for forming the carton, are provided having interlocking flanges that may be folded down into a locked configuration in a variety of sequences and that may retain the locked configuration when folds are misaligned. The carton includes a plurality of walls having locking flanges foldably attached thereto. Each one of the locking flanges is adapted to engage adjacent locking flanges in a folded configuration. Each one of the locking flanges includes a first side portion and an opposing second side portion. Each of the side portions includes a first tab, a second tab spaced apart from the first tab, and an engagement edge disposed between the first tab and the second tab. In a folded configuration, each one of the tabs and the engagement edge of a side portion engages corresponding tabs and the engagement edge of an adjacent flange side portion.

I claim:  
     
         1 . A carton having locking flanges, the carton comprising: 
 a first wall, and first flange pivotally attached thereto, the first flange having a first side portion including: 
 a first tab;  
 a second tab spaced apart from the first tab; and  
 a first engagement edge disposed between the first tab and the second tab; and  
   a second wall, pivotally coupled to the first wall, and a second flange pivotally attached to the second wall, the second flange having a first side portion proximate to the first flange first side portion; the second flange first side portion including: 
 a third tab;  
 a fourth tab spaced apart from the third tab; and  
 a second engagement edge disposed between the third tab and the fourth tab;  
   wherein the first side portions of the first and second flange are adapted to mate in a locked configuration.    
     
     
         2 . The carton of  claim 1 , wherein the carton is made from folded fiberboard.  
     
     
         3 . The carton of  claim 1 , wherein the first flange and the second flange each have a second side portion opposing the respective first side portion, each of the second side portions including: 
 a fifth tab;    a sixth tab spaced apart from the fifth tab; and    a third engagement edge disposed between the fifth tab and the sixth tab.    
     
     
         4 . The carton of  claim 3 , further comprising: 
 a third wall opposing the first wall and pivotally coupled to the second wall, and a third flange pivotally attached to the third wall, the third flange having opposing side portions, one of the third flange side portions adapted to mate with the second flange second side portion in a locked configuration; and    a fourth wall opposing the second wall and pivotally coupled to the first wall and the third wall, and a fourth flange pivotally attached to the fourth wall, the fourth flange having opposing side portions, one of the fourth flange side portions adapted to mate with one of the third flange side portions in a locked configuration, and another one of the fourth flange side portions adapted to mate with the first flange second side portion in a locked configuration;    wherein each of the third wall and fourth wall side portions includes: 
 a seventh tab;  
 a eighth tab spaced apart from the seventh tab; and  
 a fourth engagement edge disposed between the seventh tab and the eighth tab.  
   
     
     
         5 . The carton of  claim 4 , further comprising a bottom attached to each one of the walls.  
     
     
         6 . The carton of  claim 1 , wherein the first tab and the third tab extend further from their respective engagement edge than the corresponding one of the second tab and the fourth tab.  
     
     
         7 . The carton of  claim 6 , wherein the first tab and the third tab are each closer to the slot than the corresponding one of the second and the fourth tab.  
     
     
         8 . The carton of  claim 1 , wherein each of the tabs are substantially convex.  
     
     
         9 . The carton of  claim 1 , wherein the first tab and the third tab each include a rounded edge disposed proximate to their corresponding engagement surface.  
     
     
         10 . The carton of  claim 1 , wherein the second tab and the fourth tab are substantially rounded.  
     
     
         11 . A blank for forming a carton in a folded condition, the blank comprising: 
 a carton body having adjacent first and second sections for forming walls in a folded condition;    a first flange pivotally attached to the first section and having a first side portion including: 
 a first tab;  
 a second tab spaced apart from the first tab; and  
 a first engagement edge disposed between the first tab and the second tab; and  
   a second flange pivotally attached to the second section and having a second side portion, the second flange disposed adjacent to the first flange and the second side portion disposed adjacent to the first side portion of the first flange, the second side portion comprising: 
 a third tab;  
 a fourth tab spaced apart from the third tab; and  
 a second engagement edge disposed between the third tab and the fourth tab; and  
   a slot formed between the first flange and the second flange.    
     
     
         12 . The blank of  claim 11 , further comprising a pre-determined fold line formed on the carton body between the first and second section, the fold line being substantially aligned with a center of the slot.  
     
     
         13 . The blank of  claim 12 , wherein the slot is substantially wider than the fold line.  
     
     
         14 . The blank of  claim 11 , wherein the slot comprises a U-shaped slot.  
     
     
         15 . The blank of  claim 11 , wherein the first tab and the third tab extend substantially further from their respective engagement edge than the corresponding one of the second tab and the fourth tab.  
     
     
         16 . The blank of  claim 15 , wherein the first tab and the third tab are each closer to the slot than the corresponding one of the second and the fourth tab.  
     
     
         17 . The blank of  claim 11 , wherein each of the tabs are substantially convex.  
     
     
         18 . The blank of  claim 11 , wherein the first tab and the third tab each include a rounded edge disposed proximate to the corresponding engagement surface.  
     
     
         19 . The blank of  claim 11 , wherein the second tab and the fourth tab are substantially rounded.  
     
     
         20 . The blank of  claim 11 , wherein the blank is made from a fiberboard sheet.  
     
     
         21 . A carton formed from a blank, the blank including a carton body having a plurality of sections for forming walls in a folded condition and a plurality of flanges, each flange pivotally attached to a corresponding one of the sections, each flange substantially being a mirror image of an adjacent flange, each flange having a pair of opposing side portions, each side portion having a notch formed therein, each notch having an engagement edge, each side portion defining a border of a slot formed between adjacent ones of the side portions, a first projection being formed on each side portion between the corresponding slot border and the respective notch, a second projection being formed on each side portion between the respective notch and the opposing side portion of the same flange, the carton comprising: 
 a plurality of walls formed from corresponding sections of the blank;    a bottom attached to the walls;    a plurality of flanges formed from corresponding flanges of the blank, each flange pivotally attached to a corresponding one of the walls, each flange alt-superimposed with adjacent ones of the flanges in a locked configuration wherein, the notches of each flange receive one of the engagement edges of the corresponding adjacent flange, the first projections of each flange superimpose the corresponding first projections of the corresponding adjacent flanges, and the second projections of each flange superimpose corresponding second projections of an adjacent one of the flanges in an alt-superimposed configuration with their respective first projection.    
     
     
         22 . The carton of  claim 21 , wherein the slot is substantially U-shaped.  
     
     
         23 . The carton of  claim 21 , wherein the each one of the projections is rounded.  
     
     
         24 . The carton of  claim 21 , wherein the blank is made from a fiberboard sheet.  
     
     
         25 . A method of locking end flanges of a carton, the carton comprising a plurality of walls forming an inner space and having corresponding locking flanges foldably attached thereto, each one of the locking flanges having opposing side portions, each one of the side portions comprising a first tab, a second tab spaced apart from the first tab, and an engagement edge disposed between the first tab and the second tab, the method comprising: 
 selecting any one of the locking flanges as a first locking flange;    folding the first locking flange inward toward the inner space from a first position into an engagement position;    folding a second locking flange adjacent to the first locking flange inward toward the inner space from a first position into an engagement position; and    superimposing a first one of the first tab and the second tab of the second locking flange with the corresponding one of the first tab and second tab of the first locking flange; and    alt-superimposing a second one of the first tab and the second tab of the second locking flange under the corresponding second one of the first tab and second tab of the second locking flange    wherein the first tab, engagement edge, and second tab of the first locking flange engage the corresponding first tab, engagement edge, and second tab of the second locking flange in an alt-superimposed locked configuration.    
     
     
         26 . The method of  claim 25 , further comprising the step of forming the carton from a blank, the step of forming comprising the step of folding the blank along a fold line formed between the wall attached to the first locking flange and the wall attached to the second locking flange, the fold line being translated off-center from a fold line indicator, wherein the first flange and the second flange are adapted to translate along corresponding engagement surfaces in accordance with the translated fold line in the locked configuration.  
     
     
         27 . The method of  claim 25 , wherein the steps of folding the first locking flange, folding the second locking flange, superimposing, and alt-superimposing occur at substantially the same time.  
     
     
         28 . The method of  claim 25 , wherein the step of folding the first locking flange occurs first, and the steps of folding the second locking flange, superimposing, and alt-superimposing occurs at substantially the same time.  
     
     
         29 . The method of  claim 25 , wherein the step of folding the first locking flange occurs first, the step of folding the second locking flange occurs second, the step of superimposing occurs third, and the step of alt-superimposing occurs in response to the second locking flange being folded into the first locking flange.