Folding carton and blank for making folding carton

Abstract

A folding carton has a series of panels defining an internal space. A top closure flap is foldable over the top of the internal space. A top locking tab is connected to the top closure flap. The top locking tab is folded at angle for insertion into the internal space. A knob lock extends from either side of the top locking tab. The knob locks extend sufficiently from the top locking tab so that they form a frictional fit with the two of the side panels defining the internal space. A blank to form such a folding carton is also shown.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A carton comprising: 
 a first panel, a second panel, a third panel, and a fourth panel arranged to form an internal space, with the first panel adjacent to the second panel and the fourth panel, the second panel adjacent to the first panel and the third panel, the third panel adjacent to the second panel and the fourth panel, and the fourth panel adjacent to the third panel and the first panel, the first panel and the third panel being substantially parallel, and the second panel and the fourth panel being substantially parallel, the internal space having a top enclosure end and a bottom enclosure end;    a top closure flap connected to the third panel and foldable over the top enclosure end;    a top locking tab connected to the top closure flap, the top locking tab folded at angle for insertion between the first panel and the third panel, the top locking tab having a first flap side and a second flap side; and    a first knob lock extending from the first flap side of the top locking tab a sufficient distance to form a frictional fit with the first panel.    
     
     
         2 . The carton of  claim 1  further comprising a second knob lock extending from the second flap side a sufficient distance to form a frictional fit with the third panel.  
     
     
         3 . The carton of  claim 2  where the first knob lock has a first knob lock outer edge and the second knob lock has a second knob lock outer edge, and the distance from the first knob lock outer edge to the second knob lock outer edge is greater than the distance from the first panel to the third panel.  
     
     
         4 . The carton of  claim 3  where the first knob lock and the second knob lock are configured such that upon initial placement of the locking tab between the first panel and the third panel, the first knob lock is deformed so as to rest at least partially on the first panel and the second knob lock is deformed so as to rest at least partially on the third panel.  
     
     
         5 . The carton of  claim 4  where the first knob lock is deformed so that at least a portion of the first knob lock is perpendicular to the locking tab.  
     
     
         6 . The carton of  claim 5  where the second knob lock is deformed so that at least a portion of the second knob lock is perpendicular to the locking tab.  
     
     
         7 . The carton of  claim 6  where the first knob lock and the second knob locks are substantially semicircular.  
     
     
         8 . The carton of  claim 7  where first knob lock and the second knob lock have a radius, and the radius is between about {fraction (1/32)} inch and about {fraction (1/64)} inch.  
     
     
         9 . The carton of  claim 8  where first knob lock and the second knob lock have a height, and the height is greater than the radius.  
     
     
         10 . A unitary blank of foldable paperboard for use in forming a carton, the unitary blank being cut and scored to provide: 
 a back panel foldably joined along a first fold line to a left panel, the left panel foldably joined along a second fold line to a front panel, the front panel foldably joined along a third fold line to a right panel;    a top closure flap foldably joined along a fourth fold line to the front panel;    a top locking tab foldably joined along a fifth fold line to the top closure flap, the top locking tab having a first top locking tab side and a second top locking tab side; and    a first knob lock attached to the first top locking tab side, the first knob lock extending beyond the first fold line.    
     
     
         11 . The unitary blank of  claim 10  further comprising an adhesive panel, the adhesive panel connected to the back panel along a sixth fold line.  
     
     
         12 . The unitary blank of  claim 11  further comprising a second knob lock attached to the second top locking tab side, the second knob lock extending beyond the sixth fold line.  
     
     
         13 . The unitary blank of  claim 12  where the first knob lock and the second knob lock are substantially semicircular.  
     
     
         14 . The unitary blank of  claim 13  where the first knob lock and the second knob lock have a radius, and the radius is between about {fraction (1/32)} inch and about {fraction (1/64)} inch.  
     
     
         15 . The unitary blank of  claim 10  where the back panel has a back panel width, the first knob lock has a first knob lock end, the second knob lock has a second knob lock end, and the distance from the first knob lock end to the second knob lock end is greater than the back panel width.  
     
     
         16 . The unitary blank of  claim 15  where the top locking tab has a top locking tab width and a top locking length, and the top locking width is substantially less than the back panel width over most of the top locking width.  
     
     
         17 . The unitary blank of  claim 16  further comprising an adhesive panel, the adhesive panel connected to the back panel along a sixth fold line.  
     
     
         18 . The unitary blank of  claim 17  further comprising a first dust flap connected to the left panel along a seventh fold line, a second dust flap connected to the left panel along an eighth fold line, a third dust flap connected to the right panel along a ninth fold line, and a fourth dust flap connected to the right panel along a tenth fold line.  
     
     
         19 . The unitary blank of  claim 18  further comprising a bottom closure flap connected to the front panel along an eleventh fold line.  
     
     
         20 . The unitary blank of  claim 19  further comprising a bottom locking tab connected to the bottom closure flap along a twelfth fold line.