Apparatus and method for forming a bending crease in corrugated paperboard

Abstract

An apparatus for forming a bending crease in corrugated paperboard includes a circumferential portion of a wheel. The circumferential portion has a width and a peripheral surface positioned to compressively rollably receive a corrugated paperboard between the surface of the wheel and a support surface. The circumferential portion includes a protrusion extending radially outward from the circumferential portion greater than 0.070 inch. The protrusion extends radially outward from a base to a tip opposite the peripheral surface, the tip having a width less than the width of the base. The protrusion is configured to form a crease in the corrugated paperboard, the crease having sufficient depth and a width less than or equal to the width of the base, thereby resulting in a bend line formed in the corrugated paperboard that is substantially coincident with the formed crease.

What is claimed is: 
     
         1 . An apparatus for forming a bending crease in corrugated paperboard comprising:
 a circumferential portion of a wheel, the circumferential portion having a width and a peripheral surface positioned to compressively rollably receive a corrugated paperboard between the surface of the wheel and a support surface, the circumferential portion including a protrusion extending radially outward from the circumferential portion greater than 0.070 inch, the protrusion extending radially outward from a base to a tip opposite the peripheral surface, the tip having a width less than the width of the base;   wherein the protrusion is configured to form a crease in the corrugated paperboard, the crease having sufficient depth and a width less than or equal to the width of the base, thereby resulting in a bend line formed in the corrugated paperboard that is substantially coincident with the formed crease.   
     
     
         2 . The apparatus of  claim 1 , wherein at least a portion of a profile of the tip includes a curve. 
     
     
         3 . The apparatus of  claim 2 , wherein the curve includes a radius. 
     
     
         4 . The apparatus of  claim 1 , wherein the circumferential portion is composed of a metal. 
     
     
         5 . The apparatus of  claim 4 , wherein at least the tip is heat treated. 
     
     
         6 . The apparatus of  claim 3 , wherein the radius is about 0.05 inch. 
     
     
         7 . The apparatus of  claim 2 , wherein the protrusion includes a taper between the base and the tip. 
     
     
         8 . The apparatus of  claim 1 , wherein the width of the base of the protrusion is substantially equal to or less than the width of the circumferential portion. 
     
     
         9 . The apparatus of  claim 1 , wherein the circumferential portion comprises two circumferential segments. 
     
     
         10 . The apparatus of  claim 9 , wherein the two circumferential segments include mating features formed therein. 
     
     
         11 . The apparatus of  claim 10 , wherein the mating features form a dovetail joint. 
     
     
         12 . The apparatus of  claim 11 , wherein the two circumferential segments are substantially identical to each other. 
     
     
         13 . The apparatus of  claim 1 , wherein the circumferential portion and the wheel are of unitary construction. 
     
     
         14 . The apparatus of  claim 1 , wherein the tip is configured to form a perforated crease. 
     
     
         15 . A system for forming a bending crease in corrugated paperboard comprising:
 a wheel having a circumferential portion, the circumferential portion having a width and a peripheral surface positioned to compressively rollably receive a corrugated paperboard between the surface of the wheel and a support surface, the circumferential portion including a protrusion extending radially outward from the circumferential portion greater than 0.070 inch, at least a portion of the tip the protrusion having a width less than the width of the circumferential portion;   wherein the protrusion is configured to form a crease in the segment of corrugated paperboard, the crease having sufficient depth and a width less than the width of the circumferential portion, thereby resulting in a bend line formed in the segment of corrugated paperboard that is substantially coincident with the formed crease.   
     
     
         16 . The apparatus of  claim 15 , wherein at least a portion of a profile of the tip includes a curve. 
     
     
         17 . The apparatus of  claim 16 , wherein the protrusion includes a taper between the base and the tip. 
     
     
         18 . The apparatus of  claim 15 , wherein the tip is configured to form a perforated crease. 
     
     
         19 . A method for forming a bending crease in corrugated paperboard comprising:
 providing a wheel having a circumferential portion, the circumferential portion having a width and a peripheral surface positioned to compressively rollably receive a corrugated paperboard between the surface of the wheel and a support surface, the circumferential portion including a protrusion extending radially outward from the circumferential portion greater than 0.070 inch, at least a portion of the tip the protrusion having a width less than the width of the circumferential portion, the protrusion is configured to form a crease in the segment of corrugated paperboard, the crease having sufficient depth and a width less than the width of the circumferential portion, thereby resulting in a bend line formed in the segment of corrugated paperboard that is substantially coincident with the formed crease; and   directing the corrugated paperboard between the protrusion and the support surface to form the crease.   
     
     
         20 . The method of  claim 19 , wherein directing the corrugated paperboard includes directing the corrugated paperboard between the protrusion and the support surface to form a perforated crease.