Method for fabricating honeycomb material

Abstract

A process and apparatus for making expandable honeycomb structures suitable for use as window coverings. In one embodiment, folded tubular strips with adhesive lines are fed continuously through a cutter which cuts them into predetermined lengths. The cut strips are then accelerated to a stacker for further processing before the next cut strip arrives. In another embodiment, webs of material are fed continuously in a downstream direction, adhesive lines are applied, a middle web is slitted into strips, and the strips bonded along opposite edges to the outer webs. By choosing for the outer webs transparent or porous material, and for the middle web opaque material, a light or air controlling honeycomb structure results.

What is claimed is:  
     
         1 . A method of fabricating an expandable honeycomb structure comprising the steps: 
 (a) providing a continuous strip of material containing at least one line of adhesive,    (b) feeding said strip through a cutter for cutting said continuous strip into predetermined lengths,    (c) thereafter accelerating each cut strip into a downstream processor for forming the honeycomb structure,    (d) processing said cut strip in the downstream processor before the next cut strip arrives,    (e) feeding the next cut strip into the downstream processor after the previous cut strip has been processed.    
     
     
         2 . The method of    claim 1   , wherein the continuous strip of material defined in step (a) comprises a pre-creased, prefolded strip of material.  
     
     
         3 . The method of    claim 2   , further comprising the step of applying lines of adhesive to the folded strip.  
     
     
         4 . The method of    claim 3   , wherein the downstream processor pushes the cut strips into a strip stacker such that each next strip is superimposed over the previous strip.  
     
     
         5 . The method of    claim 3   , wherein the downstream processor discharges the cut strips onto a conveyor.  
     
     
         6 . The method of    claim 1   , wherein the strip feeding rate is continuous, and the cutter is synchronized to the feed rate of the continuous strip of material.  
     
     
         7 . The method of    claim 6   , wherein the accelerator for the cut strips is spaced from the cutter such that the accelerator engages and tends to accelerate the strip substantially at the time or after the time that it is severed from the continuous strip.  
     
     
         8 . Apparatus for fabricating an expandable honeycomb structure, comprising: 
 (a) means for providing a pre-creased and pre-folded continuous strip of material having lines of adhesive thereon,    (b) means for feeding said continuous strip through a cutter to sever same into predetermined lengths,    (c) means downstream of the cutter for accelerating the cut strips,    (d) means downstream of the accelerating means for processing the cut strips.    
     
     
         9 . Apparatus as claimed in    claim 8   , wherein the processing means of element (d) comprises means for receiving and stacking the cut strips.  
     
     
         10 . Apparatus as claimed in    claim 8   , wherein the processing means of element (d) comprises means for discharging the strips.  
     
     
         11 . Apparatus as claimed in    claim 8   , wherein the accelerating means of element (c) comprises a nip rotating at a speed substantially greater than the feeding means of element (b).  
     
     
         12 . Apparatus as claimed in    claim 8   , further comprising cutter means upstream of the accelerating means for cutting said continuous strip in synchronism with the feeding means of element (b) to provide predetermined lengths of cut strips.  
     
     
         13 . Apparatus as claimed in    claim 12   , wherein the means of element (d) comprises an end stop for the cut strips.  
     
     
         14 . Apparatus as claimed in    claim 13   , wherein the means of element (d) comprises means for pushing the cut strip, and means for receiving the next cut strip in superimposed relation to the previous cut strip.  
     
     
         15 . Apparatus as claimed in    claim 13   , wherein the means of element (d) comprises grooved cylinders with longitudinal parallel grooves, and means for indexing the cylinders.  
     
     
         16 . Apparatus as claimed in    claim 12   , wherein the accelerating means is spaced from the cutter a distance such that the leading edge of the next cut strip is grabbed substantially at the time that the cutter means is activated to cut the trailing edge of said strip.  
     
     
         17 . A process for fabricating an expandable honeycomb structure comprising the steps: 
 (a) feeding at least first and second webs of material in a downstream direction,    (b) feeding between the first and second webs a plurality of side-by-side strips of material,    (c) applying lines of adhesive to the webs or the strips,    (d) bringing the first and second webs and strips into juxtaposition,    (e) applying pressure or heat to cause the adhesive lines to adhere the individual strips to both the first and second webs,    (f) collecting the structure resulting from step (e).    
     
     
         18 . The process of    claim 17   , wherein the lines of adhesive applied in step (b) are applied to the first and second webs.  
     
     
         19 . The process of    claim 17   , wherein the first and second webs are optically or air transparent, and the strips are optically or air opaque.  
     
     
         20 . The process of    claim 17   , wherein the strips of step (b) are formed by slitting a third web of material.  
     
     
         21 . The process of    claim 20   , wherein the lines of adhesive applied in step (c) are applied to the third web before carrying out step (c).  
     
     
         22 . The process of    claim 20   , wherein the lines of adhesive applied in step (c) are applied to the strips after carrying out the slitting step.  
     
     
         23 . The process of    claim 17   , wherein step (f) is carried out by winding the resulting structure onto a roll.  
     
     
         21 . Apparatus for fabricating an expandable honeycomb structure, comprising: 
 (a) means for feeding at least first, second and third webs in a downstream direction,    (b) means for applying lines of adhesive to the first, second or third webs,    (c) means for forming the third web into individual strips before or after the adhesive-applying means,    (d) means downstream of the adhesive applying means for bringing the first and second webs into juxtaposition with the strips sandwiched between and for applying heat or pressure to cause the adhesive lines to adhere the individual strips to both the first and second webs to form a unitary structure.    
     
     
         24 . Apparatus as claimed in    claim 23   , wherein the means of element (c) comprises means for slitting the third web into individual strips.  
     
     
         25 . Apparatus as claimed in    claim 24   , wherein the adhesive applying means of element (b) is located upstream of the slitting means.  
     
     
         26 . Apparatus as claimed in    claim 25   , wherein the adhesive applying means of element (b) is located downstream of the slitting means.  
     
     
         27 . Apparatus as claimed in    claim 24   , wherein the adhesive applying means of element (b) is located to apply the adhesive lines to the first and second webs.  
     
     
         28 . Apparatus as claimed in    claim 24    wherein the feeding means cause the webs to feed in the same direction.  
     
     
         29 . A process for fabricating a honeycomb structure comprising the steps: 
 (a) feeding at least first and second webs of material in a downstream direction,    (b) feeding between the first and second webs a plurality of spaced apart strips of material,    (c) applying lines of adhesive to the webs or the strips,    (d) bringing the first and second webs and strips into juxtaposition,    (e) applying pressure or heat to cause the adhesive lines to adhere the individual strips to both the first and second webs,    (f) collecting the structure resulting from step (e).    
     
     
         30 . The process of    claim 29   , wherein the combined width of the strips is substantially equal to one-half of the width of a web.  
     
     
         31 . The process of    claim 29   , wherein the first and second webs are air opaque, and the strips are air opaque.  
     
     
         32 . The process of    claim 29   , wherein the resultant structure is opened up to form a honeycomb of open-ended cells, and to opposite ends of the honeycomb cells is laminated a sheet.  
     
     
         33 . The process of    claim 32   , wherein the said resultant structure is divided up into thin sections before laminating the sheets.  
     
     
         34 . Apparatus for fabricating a honeycomb structure, comprising: 
 (a) means for feeding at least first, second and third webs in a downstream direction,    (b) means for applying lines of adhesive to the first, second or third webs,    (c) means for forming the third web into individual laterally-spaced strips before or after the adhesive-applying means,    (d) means downstream of the adhesive applying means for bringing the first and second webs into juxtaposition with the laterally-spaced strips sandwiched between and for applying heat or pressure to cause the adhesive lines to adhere the individual strips to both the first and second webs to form a unitary structure,    (e) means downstream of the means of (d) for slitting the unitary structure into thin sections to form a honeycomb core.    
     
     
         35 . Apparatus as claimed in    claim 34   , wherein means are provided downstream of the means of (e) for laminating opposite sides of the resultant thin sections.