Method and Apparatus for Manufacturing Open Core Elements from Web Material

Abstract

A continuous, fully automated and highly productive system for the production of open core elements utilizes various formations of fluted input webs which are cut into strips, glued, cross-transferred, and serially upended for placement against preceding strips to build up an open core element. The open core elements are useful in the manufacture of structural members such as doors, floor panels and to wall panels. Also disclosed is a fluting apparatus effective for providing large pitch flutes for the input webs used in forming the core elements. A glue machine that utilizes a glue roll as the only moving part operates in conjunction with a ganged positive displacement adhesive pump to supply liquid adhesive for application to the flute tips for any of the various glue application stations in the system.

1 . An apparatus for forming flutes in continuous web material comprising:
 a rigid fluted rotary fluting roll with flute teeth defined by adjacent tips and gullets spaced circumferentially at a given flute pitch;   a counterroll having parallel fluting bars circumferentially spaced at the flute pitch and having fluting tips adapted to extend to the gullets of the fluting roll teeth when the counterroll is mounted for counterrotational engagement with the fluting roll;   the counterroll having a rigid cylindrical core and an outer elastomer sleeve; and,   said fluting bars embedded in said elastomer sleeve to permit individual fluting tips to move in response to fluting tip to gullet contact.   
   
   
       2 . The apparatus as set forth in  claim 1  wherein the flute teeth are generally V-shaped in cross section and the gullets have a circular cross section. 
   
   
       3 . The apparatus as set forth in  claim 2  wherein the fluting tips have a circular cross section and a radius slightly less than the radius of the gullets. 
   
   
       4 . The apparatus as set forth in  claim 3  wherein the web material has a given thickness, and the radius of the fluting tips is less than the radius of the gullets by an amount approximately equal to the web thickness. 
   
   
       5 . The apparatus as set forth in  claim 2  wherein the fluting roll flute teeth have flat flanks between adjacent tips and gullets. 
   
   
       6 . The apparatus as set forth in  claim 5  wherein the counterroll fluting bars make contact with the formed web flutes only in the flute gullets of the fluting roll. 
   
   
       7 . The apparatus as set forth in  claim 6  wherein there is no contact between the fluting roll flute tips and flute flanks of the counterroll. 
   
   
       8 . The apparatus as set forth in  claim 1  wherein said fluting roll includes a vacuum system for supplying vacuum to the flute gullets. 
   
   
       9 . The apparatus as set forth in  claim 8  including a system for heating said fluting roll. 
   
   
       10 . The apparatus as set forth in  claim 9  wherein said fluting roll comprises a cylindrical tubular body and said vacuum system and said heating system comprise axial bores formed in said tubular body. 
   
   
       11 . The apparatus as set forth in  claim 1  wherein said fluting bars comprise hollow aluminum extrusions. 
   
   
       12 . The apparatus as set forth in  claim 3  wherein the fluting bars have a teardrop cross sectional shape including a wide base embedded in the elastomer and opposite converging sides terminating in said fluting tips. 
   
   
       13 . An apparatus for applying a liquid adhesive to a moving web comprising:
 a ganged positive displacement pump having an array of laterally spaced flexible adhesive supply tubes having inlet ends receiving the adhesive from an adhesive supply and outlet ends for adhesive delivery in parallel streams;   an adhesive applicator roll arranged to receive the streams of adhesive from the outlet ends on an outer roll surface;   a flexible adhesive spreading tongue mounted adjacent the applicator roll and having a downstream end portion shaped to conform to the roll surface to spread the adhesive to a uniform layer on the rotating roll; and,   a web delivery arrangement for bringing the web into tangent contact with the roll downstream of the end of the tongue to pick up adhesive from the roll surface.   
   
   
       14 . The apparatus as set froth in  claim 13  wherein the pump comprises a peristaltic pump and includes a pump housing having a semicylindrical backing surface and a driven rotating roller assembly having an axis of rotation coincident with the axis of the backing surface and operable to intermittently press the tubes against the backing surface to deliver laterally spaced uniform streams of adhesive. 
   
   
       15 . The apparatus as set forth in  claim 14  wherein the inlet ends of the pump supply tubes receive from the adhesive supply the proper volume of adhesive to be applied to the web, whereby no adhesive supplied by the pump to the applicator roll must be recycled. 
   
   
       16 . The apparatus as set forth in  claim 15  wherein the adhesive is an aqueous starch-based glue and including means for calculating the volume of adhesive based on pump rotational speed, web speed and web width to supply the proper volume of adhesive to the pump. 
   
   
       17 . The apparatus as set forth in  claim 14  including a device for mounting the outlet ends of the supply tubes adjacent the applicator roll at a selectively adjustable lateral spacing. 
   
   
       18 . The apparatus as set forth in  claim 17  wherein the tube end mounting device comprises an elastic band to which the tube ends are attached at a selected uniform lateral spacing in a partially stretched condition and with which tube spacing is increased by stretching the band in opposite directions by equal amounts. 
   
   
       19 . The apparatus as set forth in  claim 13  including laterally adjustable adhesive layer width controls operative to contact the roll surface and remove therefrom adhesive lying laterally beyond the width of the web. 
   
   
       20 . The apparatus as set forth in  claim 19  wherein the width controls comprise vacuum assisted doctor blades. 
   
   
       21 . The apparatus as set forth in  claim 13  including a roll cleaning doctor blade extending the full length of the roll and movable vertically into reverse angled contact with the roll surface downstream of the end of the tongue. 
   
   
       22 . The apparatus as set forth in  claim 21  including means for circulating cleaning solution through the pump tubes and over the roll, the tongue, the vacuum assisted doctor blades and roll cleaning doctor blade. 
   
   
       23 . The apparatus as set forth in  claim 13  including means for adjusting the axial positions of portions of the tubes pressed by the roller assembly to present fresh portions to contact by the roller assembly.