Foldable Composite Panel with Compression Relief Hinge

Abstract

According to an exemplary embodiment, a composite panel includes a primary layer ( 102, 120 a ) that includes a primary hinge ( 122 a ). The primary hinge ( 122 a ) is defined by at least one fold line. The composite panel further includes a reinforcing layer ( 110, 136 a ) that includes a compression relief hinge ( 140 a ). The compression relief hinge ( 140 a ) is defined by a pair of distal fold lines ( 142 a , 146 a ) and a medial fold line ( 144 a ) that Is disposed between and spaced apart from the distal fold lines ( 142 a , 146 a ). The primary hinge ( 122 a ) overlies the compression relief hinge ( 140 a ) so that when the composite panel is folded about the primary hinge ( 122 a ), the composite relief hinge ( 140 a ) buckles away from the primary hinge ( 122 a ).

1 . A foldable panel of composite sheet material for forming at least a portion of a carton, the panel comprising:
 a primary layer comprising a primary hinge, the primary hinge comprising at least one fold line;   a reinforcing layer comprising a compression relief hinge, the compression relief hinge comprising:
 a pair of distal fold lines; and 
 at least one medial fold line disposed between and spaced apart from the pair of distal fold lines; 
   wherein:
 at least a portion of the reinforcing layer is secured to the primary layer; and 
 the primary hinge and the compression relief hinge are aligned. 
   
   
   
       2 . The foldable panel of  claim 1 , wherein the primary hinge is aligned with the compression relief hinge such that the primary hinge is disposed between the pair of distal fold lines. 
   
   
       3 . The foldable panel of  claim 1 , wherein the width of the medial fold line is greater than the width of the distal fold lines. 
   
   
       4 . The foldable panel of  claim 1 , wherein the medial fold line comprises a plurality of adjacent weakened lines. 
   
   
       5 . The foldable panel of  claim 1 , wherein the distance between the medial fold line and a distal fold line is a function of the thicknesses of the layers. 
   
   
       6 . The foldable panel of  claim 1 , wherein the distal fold lines are formed in a first surface of the reinforcing layer and the medial fold line is formed in a second surface of the reinforcing layer. 
   
   
       7 . The foldable panel of  claim 1 , wherein bulge panels are defined by the distal fold lines and the medial fold line. 
   
   
       8 . The foldable panel of  claim 1 , wherein the compression relief hinge can fold along the distal fold lines and the medial fold line to form a furrow as the foldable panel is folded along the primary hinge. 
   
   
       9 . The foldable panel of  claim 4 , wherein at least one of said plurality of adjacent weakened lines is comparatively weaker than the other of said plurality adjacent weakened lines. 
   
   
       10 . The foldable panel of  claim 9 , wherein said plurality of adjacent weakened lines comprises a pair of endmost weakened lines and at least one centermost weakened line, wherein said at least one centermost line comprises said comparatively weaker line. 
   
   
       11 . The foldable panel of  claim 9 , wherein said comparatively weaker line comprises any of the following: slit; cut; half cut; score; crimp; and perforation. 
   
   
       12 . The foldable panel of  claim 1 , wherein said primary layer is secured to said reinforcing layer on opposite sides of said compression relief hinge. 
   
   
       13 . The foldable panel of  claim 1 , wherein at least one of said distal fold lines is formed from a plurality of substantially parallel adjacent weakened lines. 
   
   
       14 . The foldable panel of  claim 1 , wherein said primary hinge comprises a plurality of substantially parallel fold lines formed in said primary layer. 
   
   
       15 . A method for forming a corner of a carton by folding a composite panel formed from at least a primary layer and a reinforcing layer, the method comprising:
 defining a primary hinge in said primary layer;   securing at least a portion of said reinforcing layer to said primary layer on both sides of said primary hinge; and   defining a compression relief hinge in said reinforcing layer, comprising:
 defining a medial fold line; 
 aligning said medial fold line with said primary hinge; and 
 defining at least a first and a second distal fold line each being substantially parallel to said medial fold line, said medial fold line being disposed between said distal fold lines and being spaced apart from each of said distal fold lines. 
   
   
   
       16 . The method of  claim 15 , wherein said primary hinge extends at least partially across said primary layer. 
   
   
       17 . The method of  claim 15 , wherein said medial fold line comprises at least three weakened lines. 
   
   
       18 . The method of  claim 17 , wherein at least a centermost one of said weakened lines is weaker than the outermost ones of said weakened lines. 
   
   
       19 . The method of  claim 15 , wherein defining said medial fold line comprises creating a score line in said reinforcing layer and extensively weakening a centermost portion of said score line. 
   
   
       20 . The method of  claim 15 , further comprising folding said composite panel along said primary hinge such that said compression relief hinge buckles away from said primary hinge.