Polygonal box

Abstract

A polygonal box comprises faces ( 1, 2, 3 ), a lid ( 7 ) provided with a tab ( 8 ) suitable for arranging in a folded position against a first face ( 1 ) of the box, and a flap ( 9 ) that can be folded down around an edge ( 29 ) shared with a second face ( 2 ) of the box, the flap ( 9 ) having a zone ( 10 ) of mechanical weakening that is inclined relative to said edge ( 29 ). The inclined zone ( 10 ) of weakening does not tear when the box is packed industrially and shows up first opening of the box by tearing-away of a surface ( 12 ) of the flap at the time of said first opening (FIG. 2 ).

1 . A polygonal box comprising: 
 at least three faces ( 1 ,  2 ,  3 );    a lid ( 7 ) provided with a tab ( 8 ) suitable for arranging in a folded position against a first face ( 1 ) of the box; and    a flap ( 9 ) that can be folded down around an edge ( 29 ) shared with a second face ( 2 ) of the box, the flap ( 9 ) having a zone ( 10 ) of mechanical weakening that is inclined relative to said edge ( 29 ).    
   
   
       2 . The polygonal box as set forth in  claim 1 , wherein the flap ( 9 ) has a first surface ( 11 ) delimited by the edge ( 29 ) shared with the second face ( 2 ) and by the zone ( 10 ) of weakening, and a second surface ( 12 ) delimited by the zone ( 10 ) of weakening and by the end of the flap ( 9 ) opposite the edge ( 29 ), said first surface ( 11 ) being larger than said second surface ( 12 ), and the second surface ( 12 ) being designed to be pinched between the tab ( 8 ) and the lid ( 7 ) and torn away by tearing of the zone ( 10 ) of weakening when the tab ( 8 ) is unfolded from its position against the first face of the box.  
   
   
       3 . The polygonal box as set forth in  claim 1 , wherein the flap ( 9 ) has lateral borders extending from the edge ( 29 ) shared with the second face ( 2 ), the zone ( 10 ) of weakening extending in a curved line from a lateral border of the flap.  
   
   
       4 . The polygonal box as set forth in  claim 2 , wherein the flap ( 9 ) has lateral borders extending from the edge ( 29 ) shared with the second face ( 2 ), the zone ( 10 ) of weakening extending in a curved line from a lateral border of the flap.  
   
   
       5 . The polygonal box as set forth in  claim 3 , wherein the curve of the zone ( 10 ) of weakening is concave along the first surface ( 11 ).  
   
   
       6 . The polygonal box as set forth in  claim 4 , wherein the curve of the zone ( 10 ) of weakening is concave along the first surface ( 11 ).  
   
   
       7 . The polygonal box as set forth in  claim 5 , wherein the curve of the zone ( 10 ) of weakening defines an arc of a circle with a diameter greater than or equal to the edge ( 29 ) shared by the flap and a face.  
   
   
       8 . The polygonal box as set forth in  claim 6 , wherein the curve of the zone ( 10 ) of weakening defines an arc of a circle with a diameter greater than or equal to the edge ( 29 ) shared by the flap and a face.  
   
   
       9 . The polygonal box as set forth in  claim 7 , wherein the diameter of the arc of the circle of the curve of the zone ( 10 ) of weakening is between from about 100% and about 150% of the length of the edge ( 29 ) shared by the flap and a face.  
   
   
       10 . The polygonal box as set forth in  claim 8 , wherein the diameter of the arc of the circle of the curve of the zone ( 10 ) of weakening is between from about 100% and about 150% of the length of the edge ( 29 ) shared by the flap and a face.  
   
   
       11 . The polygonal box as set forth in  claim 1 , wherein the flap ( 9 ) has lateral borders extending from the edge ( 29 ) shared with a face ( 2 ), the inclined zone ( 10 ) of weakening extending in a straight line from a lateral border of the flap.  
   
   
       12 . The polygonal box as set forth in  claim 2 , wherein the flap ( 9 ) has lateral borders extending from the edge ( 29 ) shared with a face ( 2 ), the inclined zone ( 10 ) of weakening extending in a straight line from a lateral border of the flap.  
   
   
       13 . The polygonal box as set forth in  claim 11 , wherein the angle (α) of inclination of the zone ( 10 ) of weakening relative to the edge ( 29 ) shared by the flap and a face is between from about 10° and about 80°.  
   
   
       14 . The polygonal box as set forth in  claim 12 , wherein the angle (α) of inclination of the zone ( 10 ) of weakening relative to the edge ( 29 ) shared by the flap and a face is between from about 10° and about 80°.  
   
   
       15 . The polygonal box as set forth in  claim 1 , which further comprises a zone ( 15 ) of weakening arranged on the first face ( 1 ) opposite the tab ( 8 ) in the folded position.  
   
   
       16 . The polygonal box as set forth in  claim 15 , wherein the zone ( 15 ) of weakening of the first face is an arc of a circle of which the ends are arranged on an edge of the first face ( 1 ).  
   
   
       17 . The polygonal box as set forth in  claim 15 , which further comprises zones ( 16 ,  17 ) of weakening arranged on the lid ( 7 ).  
   
   
       18 . The polygonal box as set forth in  claim 17 , wherein the zone ( 16 ) of weakening of the lid is an arc of a circle of which the ends are arranged on an edge ( 18 ) shared by the lid ( 7 ) and the tab ( 8 ).  
   
   
       19 . The polygonal box as set forth in  claim 17 , wherein the zone ( 17 ) of weakening of the lid is a line extending from an edge ( 18 ) shared by the lid ( 7 ) and the tab ( 8 ) toward a lateral border of the lid extending from said edge.  
   
   
       20 . The polygonal box as set forth in  claim 18 , wherein the zone ( 17 ) of weakening of the lid is a line extending from an edge ( 18 ) shared by the lid ( 7 ) and the tab ( 8 ) toward a lateral border of the lid extending from said edge.  
   
   
       21 . The polygonal box as set forth in  claim 1 , wherein the zone ( 10 ) of weakening comprises perforations.  
   
   
       22 . The polygonal box as set forth in  claim 15 , wherein the zones ( 10 ,  15 ) of weakening comprise perforations.  
   
   
       23 . The polygonal box as set forth in  claim 16 , wherein the zones ( 10 ,  15 ) of weakening comprise perforations.  
   
   
       24 . The polygonal box as set forth in  claim 17 , wherein the zones ( 10 ,  15 ,  16 ,  17 ) of weakening comprise perforations.  
   
   
       25 . The polygonal box as set forth in  claim 1 , which comprises four faces ( 1 ,  2 ,  3 ,  4 ).  
   
   
       26 . The polygonal box as set forth in  claim 1 , which is composed mostly of cardboard.  
   
   
       27 . A pre-cut-out blank comprising: 
 fold zones for forming the edges of the box according to  claim 1;  and    a zone ( 10 ) of weakening extending over a portion of the blank designed to form a flap ( 9 ), this zone ( 10 ) extending in a line that is inclined relative to an edge ( 29 ) shared by the flap ( 9 ) and a face of the box as set forth in  claim 1.