Patent Publication Number: US-2007107176-A1

Title: Apparatus for fabricating venetian blinds with tubular fabric slats

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      The present application claims the benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 60/728,606 (“the &#39;606 application”), which was filed on Oct. 20, 2005 and entitled “Apparatus For Fabricating Venetian Blinds With Tubular Fabric Slats.” The &#39;606 application is incorporated by reference into the present application in its entirety. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates generally to Venetian blind type coverings for architectural openings such as windows, doors, archways, and the like, and more particularly to an apparatus for fabricating a panel for use in a Venetian blind utilizing tubular fabric slats.  
      2. Description of the Relevant Art  
      Coverings for architectural openings such as windows, doors, archways, and the like, have taken numerous forms for many years. Illustrative of such coverings are draperies, curtains, retractable shades including continuous roll-up shades or cellular shades, and retractable blinds such as Venetian blinds and vertical blinds. Of these coverings, Venetian blinds are a very popular product and are typically made with a plurality of horizontally extending slats that may be aluminum or wood which are supported on tape or cord ladders for movement between extended and retracted positions relative to the architectural opening. In the retracted position, the slats are accumulated in a stack adjacent the top edge of the opening and in an extended position are evenly distributed vertically across the opening. Lift cords extend through the slats and are connected to a bottom rail at their lower end and a retracting mechanism in a headrail at their upper end so that by shortening the effective length of the lift cords, the slats are progressively accumulated until fully retracted in a neat stack at the top of the opening. The tape or cord ladders have front and rear vertical runners that are interconnected at spaced locations along their length by horizontal rungs which support the slats at horizontally spaced locations along the length of the horizontally extending slats. By shifting the front and rear vertical rungs in opposite vertical directions, the rungs are caused to tilt from their neutral horizontal orientation thereby tilting the slats supported thereon so as to move the slats between open and closed positions. In the open position, the slats are horizontally deployed with spaces therebetween through which light and vision can pass while in the closed position, the slats are substantially vertically oriented and overlap slightly to block vision and light through the covering.  
      Such Venetian blinds are made in numerous ways but typically with separate machines with one machine forming the slats either of a flat wood product or from aluminum, in which case the slats are provided with an arcuate transverse cross section, and the other machine inserting the slats into a plurality of tape or cord ladders by positioning each slat between the front and rear vertical runners and on top of a rung. The tape or cord ladders with the slats incorporated therein are subsequently incorporated into the operating mechanism in the headrail for the blind for opening and closing the blind in a conventional manner. Integrated apparatus for making an aluminum slatted Venetian blind are also known in the art such as for example shown in U.S. Pat. No. 5,349,730.  
      As will be appreciated from the above, prior art Venetian blind products have limited aesthetic appeal in that the primary component consists of wooden or metal slats and, accordingly, slats of a more attractive nature would likely enhance the aesthetics of the product. Further, it would be desirable to have an automated system for making Venetian blind type products of varying widths and with enhanced aesthetics in an in-line uninterrupted apparatus.  
     SUMMARY OF THE INVENTION  
      The present invention is an apparatus and method for fabricating panels for Venetian blind products or subassemblies and more specifically the retractable panel component of a Venetian blind. The apparatus provides for a continuous in-line process with the final panel including a plurality of tubular fabric vanes operatively positioned within and secured to cord ladders. The apparatus includes a vane-forming system, a vane-sizing system, and a panel fabrication system. In the apparatus, a strip of fabric material is progressively folded into a tubular product so that one longitudinal edge of the strip can be secured to the opposite longitudinal edge to enclose the tubular product, the product is cut to a length determined by the desired width of the covering through the use of templates of various lengths and finally the cut tubular vanes are inserted longitudinally and horizontally into vertically suspended cord ladders immediately beneath associated rungs of the cord ladders. The slats are subsequently secured to the rungs. The covering is assembled in a rising fashion by lifting the cord ladders in stepped unison as additional slats are incorporated into the cord ladders.  
      Other aspects, features, and details of the present invention can be more completely understood by reference to the following detailed description of a preferred embodiment, taken in conjunction with the drawings and from the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an isometric of the apparatus of the present invention.  
       FIG. 2A  is a fragmentary isometric showing the panel assembly system of the apparatus of  FIG. 1 .  
       FIG. 2B  is a fragmentary isometric showing the vane-sizing system and part of the vane-forming system of the apparatus of  FIG. 1 .  
       FIG. 2C  is a fragmentary isometric showing a portion of the vane-forming system of the apparatus of  FIG. 1 .  
       FIG. 3A  is a fragmentary isometric similar to  FIG. 2A  showing completed vanes incorporated into cord ladders in the apparatus.  
       FIG. 3B  is a fragmentary isometric similar to  FIG. 2B  showing transfer belts transferring the vane through the apparatus.  
       FIG. 3C  is a fragmentary isometric similar to  FIG. 2C  with vane-strip material incorporated into the apparatus.  
       FIG. 4A  is a diagrammatic plan view of the apparatus of  FIG. 1 .  
       FIG. 4B  is a diagrammatic plan view similar to  FIG. 4A  with belts incorporated into the apparatus.  
       FIG. 4C  is a diagrammatic plan view similar to  FIG. 4B  with the vane material incorporated into the apparatus.  
       FIG. 4D  is a diagrammatic plan view similar to  FIG. 4C  with the apparatus utilizing five cord ladder systems instead of three.  
       FIG. 4E  is a diagrammatic plan view similar to  FIG. 4D  with the apparatus utilizing four cord ladder systems instead of five.  
       FIG. 4F  is a diagrammatic plan view similar to  FIG. 4E  with the apparatus utilizing two cord assemblies instead of four.  
       FIG. 4G  is a diagrammatic plan view similar to  FIG. 4F  with the two utilized cord systems being positioned more closely together.  
       FIG. 4H  is a diagrammatic top plan view of the apparatus.  
       FIG. 4J  is a diagrammatic side elevation of the apparatus as shown in  FIG. 4H .  
       FIG. 5  is a fragmentary isometric illustrating a portion of the vane-forming system.  
       FIG. 6  is an enlarged section taken along line  6 - 6  of  FIG. 5 .  
       FIG. 7  is an enlarged fragmentary section taken along line  7 - 7  of  FIG. 3C .  
       FIG. 8  is a section similar to  FIG. 7  with the vane material having been removed.  
       FIG. 9  is an enlarged vertical section taken along line  9 - 9  of  FIG. 7 .  
       FIG. 10  is an enlarged vertical section taken along line  10 - 10  of  FIG. 7 .  
       FIG. 11  is an enlarged vertical section taken along line  11 - 11  of  FIG. 7 .  
       FIG. 12  is an enlarged vertical section taken along line  12 - 12  of  FIG. 7 .  
       FIG. 13  is an enlarged fragmentary section taken along line  13 - 13  of  FIG. 3C .  
       FIG. 14  is an enlarged fragmentary section taken along line  14 - 14  of  FIG. 3C .  
       FIG. 15  is an enlarged fragmentary section taken along line  15 - 15  of  FIG. 3C .  
       FIG. 16  is an enlarged fragmentary section taken along line  16 - 16  of  FIG. 7 .  
       FIG. 17  is an enlarged section taken along line  17 - 17  of  FIG. 3C .  
       FIG. 18  is an enlarged fragmentary section taken along line  18 - 18  of  FIG. 3B .  
       FIG. 19  is an enlarged fragmentary section taken along line  19 - 19  of  FIG. 18 .  
       FIG. 20  is an enlarged fragmentary section taken along line  20 - 20  of  FIG. 3B .  
       FIG. 21  is a fragmentary isometric looking from the rear of the apparatus at the heating system of the vane-forming system.  
       FIG. 22  is a fragmentary isometric similar to  FIG. 21  with the belts and vane material removed.  
       FIG. 23  is a fragmentary isometric taken generally along line  23 - 23  of  FIG. 3B .  
       FIG. 24  is an isometric looking upwardly at the bottom of the upper component of the first vane compression block.  
       FIG. 25  is an isometric looking downwardly on the bottom portion of the first vane compression block.  
       FIG. 26  is an isometric of the vane material being completed in the compression block of  FIGS. 24 and 25  with the lower component being shown in full line and the upper component in dashed lines.  
       FIG. 27  is an enlarged fragmentary section taken along line  27 - 27  of  FIG. 26 .  
       FIG. 28  is an enlarged fragmentary section taken along line  28 - 28  of  FIG. 26 .  
       FIG. 29  is an enlarged fragmentary section taken along line  29 - 29  of  FIG. 26 .  
       FIG. 30  is a fragmentary isometric of the end of the vane-forming system and the beginning of the panel assembly system showing driven and idler rollers associated with various belts used in the apparatus.  
       FIG. 31  is a fragmentary isometric of the same general area illustrated in  FIG. 30  with components removed for clarity and viewed from the back side of the apparatus.  
       FIG. 32  is a fragmentary section similar to  FIG. 31  with the strip of vane material included and showing portions of the vane-sizing system.  
       FIG. 33  is a fragmentary isometric similar to  FIG. 32  with the drive belts included in the view.  
       FIG. 34  is an enlarged fragmentary section taken along line  34 - 34  of  FIG. 33 .  
       FIG. 35  is an isometric looking downwardly on a cord ladder assembly.  
       FIG. 36  is a fragmentary front elevation of the cord ladder assembly shown in  FIG. 35 .  
       FIG. 37  is a fragmentary rear elevation of the cord ladder assembly of  FIG. 36 .  
       FIG. 38  is an isometric of the various vane templates used in the apparatus of the invention for setting vane lengths.  
       FIG. 39  is a fragmentary elevation of the length-setting device used in the vane-sizing system of the invention with the device in a retracted position.  
       FIG. 40  is a fragmentary elevation similar to  FIG. 39  with the device in a locking or extended position.  
       FIG. 41  is a fragmentary isometric of the downstream end of the apparatus showing the length-setting device in cooperation with a vane template and portions of the cable system used in the vane-sizing system.  
       FIG. 42  is a fragmentary isometric similar to  FIG. 41  with the cables removed.  
       FIG. 43  is a vertical section through the cord ladder assembly of  FIG. 35 .  
       FIG. 43A  is a vertical section similar to  FIG. 43  with the vane material and cord ladder material removed.  
       FIG. 44  is an enlarged fragmentary section taken along line  44 - 44  of  FIG. 43 .  
       FIG. 45  is a fragmentary section similar to  FIG. 44  with the locking bumper in a locking position.  
       FIG. 46  is a fragmentary section taken along line  46 - 46  of  FIG. 44 .  
       FIG. 47  is a fragmentary section taken along line  47 - 47  of  FIG. 45 .  
       FIG. 48  is an enlarged horizontal section similar to  FIG. 47  showing a vane in end engagement with the bumper.  
       FIG. 49  is a horizontal section similar to  FIG. 48  with a vane having been rebounded by the bumper.  
       FIG. 50  is a fragmentary isometric showing the bumper in the position of  FIG. 49 .  
       FIG. 51  is a fragmentary isometric similar to  FIG. 50  with a vane shown in dashed lines initially engaging the bumper.  
       FIG. 52  is a fragmentary vertical section similar to  FIG. 43  with the bumper in a retracted position so that the cord ladder assembly illustrated is an intermediate assembly and not the terminal assembly shown in  FIG. 43 .  
       FIG. 53  is a fragmentary section taken along line  53 - 53  of  FIG. 52 .  
       FIG. 54  is a fragmentary section taken along line  54 - 54  of  FIG. 52 .  
       FIG. 55  is a horizontal section taken along line  55 - 55  of  FIG. 57  showing the cord ladder spreader.  
       FIG. 56  is a section taken along line  56 - 56  of  FIG. 57 .  
       FIG. 57  is a fragmentary isometric showing a portion of the lift tower of the cord ladder assembly of  FIG. 35 .  
       FIG. 58  is an isometric of a lift belt used in the lift tower of  FIG. 57 .  
       FIG. 59  is an enlarged fragmentary isometric of a portion of the lift belt shown in  FIG. 58 .  
       FIG. 60  is an isometric of a cord ladder vertical riser guide.  
       FIG. 61  is an isometric of a vane detector for detecting the receipt of a vane in the panel assembly system.  
       FIG. 62  is an isometric of a belt spreader used in the panel assembly system.  
       FIG. 63  is a fragmentary isometric showing a cord ladder extending through the lift tower.  
       FIG. 64  is an enlarged fragmentary isometric at a location immediately above that shown in  FIG. 63 .  
       FIG. 65  is a fragmentary isometric at a location immediately above that shown in  FIG. 64 .  
       FIGS. 65A-65F  are diagrammatic views illustrating the insertion of tubular slats into cord ladders and the repositioning of the cord ladders to engage the slat with a corresponding rung.  
       FIG. 66  is an isometric of the adhesive application device used to secure the slats to rungs of cord ladders.  
       FIG. 67  is an enlarged top plan view of the device shown in  FIG. 66 .  
       FIG. 68  is an enlarged bottom plan view of the device shown in  FIG. 66 .  
       FIG. 69A  is a fragmentary vertical section taken along line  69 A- 69 A of  FIG. 67 .  
       FIG. 69B  is a fragmentary isometric of the device as shown in  FIG. 69A .  
       FIG. 70A  is a fragmentary section similar to  FIG. 69A  with the adhesive application device in an advanced position in alignment with vanes in the vane assembly system.  
       FIG. 70B  is an isometric of the adhesive application device as shown in  FIG. 70A .  
       FIG. 71A  is a fragmentary vertical section similar to  FIG. 70A  with the application device components in an active position.  
       FIG. 71B  is a fragmentary isometric of the adhesive application device in the position of  FIG. 71A .  
       FIG. 72  is an enlarged fragmentary vertical section taken along line  72 - 72  of  FIG. 71A .  
       FIG. 73  is an enlarged fragmentary vertical section taken along line  73 - 73  of  FIG. 71A .  
       FIG. 73A  is a section similar to  FIG. 73  with the gas-controlling plunger in an extended closing position.  
       FIG. 74  is an enlarged fragmentary vertical section taken along line  74 - 74  of  FIG. 71A .  
       FIG. 75  is a fragmentary isometric similar to  FIG. 70B  from the opposite side of the apparatus. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      The apparatus  80  of the present invention for fabricating panels of material used as subassemblies in Venetian blinds is an automatic in-line system. The apparatus is designed to fabricate a panel comprised of a plurality of conventional cord ladders interconnected with tubular fabric vanes. The panel can then be incorporated into a Venetian blind by securing the panel along its lower edge to a conventional bottom rail (not shown) and along its top edge to a conventional headrail (not shown) that incorporates an operating system for extending and retracting the panel across an architectural opening and for pivoting the tubular slats or vanes about their longitudinal axes which extend horizontally across the architectural opening. For purposes of the present disclosure, the bottom rail, the headrail, and the operating system will not be described as the present invention is directed solely to the fabrication of the panel or subassembly described above that forms part of a completed Venetian blind.  
      It is also to be understood that the description of the apparatus that follows will reference various motors and a control system but the specifics will not be described. The control system for operating the apparatus is felt to be within the skill of one in the art and is preferably a pneumatic system controlled by a computer which controls the various motors and other pneumatic components utilized in the apparatus in accordance with the operation described in detail hereafter.  
      With reference to  FIG. 1 , the apparatus  80  of the invention includes a vane-forming system  82  at the upstream end of the apparatus shown to the right in  FIG. 1 , a vane-sizing system  84 , and a panel-assembly system  86  at the downstream end of the apparatus shown on the left in  FIG. 1 . The vane-sizing system extends between and overlaps the panel-assembly system and the vane-forming system as will be explained in more detail later.  
      The illustration of the apparatus  80  in  FIG. 1  does not include the cord ladder materials used in the panel fabricated with the apparatus nor does it include the fabric strip material from which the vanes for the panel are formed. These materials will be shown and described hereafter.  
      In the vane-forming system  82  ( FIG. 3C ), a supply roll  88  of fabric strip material  90  is provided that might be resin impregnated fiberglass having a crease  92  approximately along its longitudinal centerline and an elongated bead of inert (non-sticky) adhesive  94  along one edge and on one face of the strip material. The strip material is fed through a forming station  96  where it is folded along the longitudinal crease  92 , the inert adhesive  94  along the edge of the strip is heated for activation (making it tacky) and that edge of the strip material is folded over and secured to the adjacent opposite edge to form a relatively flat tubular vane. During the forming process, a cutter cuts the strip material into predetermined lengths corresponding to the predetermined width of the panel to be formed in the apparatus. Each cut strip, which is ultimately completed into a tubular vane, is advanced into a predetermined number of cord ladders  98  ( FIG. 3A ) positioned for receipt of the vanes in the panel-forming system and sequentially secured to the cord ladders until a predetermined number of vanes have been secured thereto dependent upon the height of the panel  100  ( FIG. 3A ) to be formed. The apparatus includes a plurality of cord ladder assemblies  102  ( FIG. 1 ) associated with individual rolls ( FIG. 3A ) of cord ladder material and two or more of the cord ladder assemblies are utilized in the fabrication of a panel depending upon the width of the panel being formed. In other words, the longer the panel  100  being formed, the more cord ladders  98  desired for the panel and the more cord ladder assemblies  102  put into operation. It will also be appreciated from the description that follows that the entire apparatus is mounted on a suitable frame that will not be described in detail other than the pertinent parts thereof necessary for an understanding of the mechanics and operation of the apparatus.  
       FIGS. 4A-4J  are diagrammatic top plan views of the apparatus  80  which are felt to be helpful in an understanding of the description of the apparatus that follows.  FIG. 4A  is such a diagrammatic plan view with the belts, cables and materials used in fabricating the panel having been removed.  FIG. 4B  is a view similar to  FIG. 4A  wherein belts, cables, and the like have been added but wherein none of the supply material used in fabricating the panel are included.  FIG. 4C  is a view similar to  FIG. 4B  with the vane strip material  90  having been added and wherein the apparatus is arranged for utilizing three cord ladder assemblies  102  in the assembly of a panel  100 .  FIG. 4D  is a plan view similar to  FIG. 4C  wherein the apparatus is set up for fabricating a panel  100  with five cord ladders  98 .  FIG. 4E  is a similar view to  FIG. 4D  but wherein the apparatus is set up for forming a panel with four cord ladders, and  FIG. 4F  is a similar view wherein the apparatus is set up for assembling a panel with only two cord ladders.  FIG. 4G  is a view similar to  FIG. 4F  but wherein the three cord ladder assemblies  102  not being utilized in the fabrication of a panel have been stacked in a non-operative position at the downstream end of the apparatus.  FIG. 4H  is a top plan view of the apparatus with the vane strip material  90  positioned for initially operating the apparatus, i.e. with the vane strip material having been fed through the upstream portion of the vane-forming system  82  up to the cutter.  FIG. 4J  is a side elevation of the apparatus as shown in  FIG. 4H .  
       FIG. 2A  is an isometric of the panel assembly system  86  with  FIGS. 2B and 2C  showing the vane-forming system  82  and portions of the vane-sizing system  84 .  FIGS. 3A, 3B , and  3 C complement  FIGS. 2A, 2B , and  2 C by incorporating the component supply materials needed to fabricate a panel for a Venetian blind, namely the cord ladder material  98  and the vane strip material  90 . Looking first at  FIGS. 2C and 3C , the vane-forming system  82  at the extreme upstream end of the apparatus can be seen to include a fixed circular supply tray  104  having a freely rotatable spindle  106  at its center rotatable about a vertical axis and aligned with a brake  108  therebeneath, an accumulator box  110 , a plurality of staged and stepped folding blocks  112 , a first folding and aligning housing  114  and a cutter  116  for cutting a folded strip of vane material  90  into predetermined lengths.  
      By reference to  FIG. 3C , the supply roll  88  of vane strip material  90  is shown mounted on the spindle  106  with the strip material being a flexible flat material with the flat dimension extending vertically and having been fed through the accumulator  110  and subsequently the folding blocks  112  and the first folding and aligning housing  114  into the cutter  116 . Between the first folding and aligning housing and the cutter are pairs of driven rollers  118  having a friction surface for gripping the strip material. The rollers  118  are intermittently activated to pull vane strip material from the accumulator, through the folding blocks, and the first folding and aligning housing and feed it downstream past the cutter to a first set of upper and lower drive belts  130  and  132  and to a pair of photoelectric sensors  120  possibly seen best in  FIGS. 4B and 18 . There are two photoelectric sensors mounted on a common block  122  so that one sensor is upstream from the other. The sensors are adapted to sense the leading or downstream cut edge of a strip of the vane material  90  and position that edge at a predetermined distance from the cutter with that distance correlating to the length of the vane  124  ( FIG. 3A ) desired for a panel  100  being fabricated with the apparatus. The photoelectric sensors are part of the vane-sizing system  84  to be described in more detail hereafter. The block  122  on which the sensors are mounted is movable between fixed predetermined positions spaced from the cutter a distance depending upon the width of the panel being fabricated.  
      As will be explained in more detail hereafter, when the sensors  120  are desirably positioned for dictating a predetermined length of strip of material  90  to be cut into a vane, the pairs of driven rollers  118  are activated to advance the folded strip of vane material to the first set of drive belts  130  and  132  that in turn advance the vane material downstream at a high speed until the first edge of the vane is detected by the upstream sensor at which time the speed of the drive belts is decreased radically until the leading edge of the vane strip material is sensed by the downstream sensor at which time the rotation of the drive belts is stopped. The cutter  116  can then be activated to cut the vane strip material to the predetermined length corresponding to the spacing between the downstream most sensor and the cutter blade  126  ( FIG. 16 ).  
      The cutter  116  is a conventional guillotine type cutter probably best seen in  FIG. 16  having a pneumatic cylinder  128  for advancing the cutter blade  126  through the vane strip material  90  and retracting the knife blade in a very short period of time. After a folded strip of vane strip material has been cut to the predetermined length, it is advanced further downstream by the upper and lower conveyor drive belts  130  and  132  respectively ( FIG. 16 ) between which it is confined through a heating and adhesive activation station  134  ( FIG. 20 ), a second folding housing  136  ( FIG. 30 ) and finally into the panel-assembly system  86  as will be described in more detail hereafter.  
      With reference to  FIGS. 5 and 6 , the upstream end of the apparatus is illustrated with a roll  88  of vane strip material  90  mounted on the spindle  106  and the leading edge of the material fed through the vane-forming system  82  up to the friction rollers  118 . As will be appreciated, the roll of vane strip material is positioned on the spindle so that the strip material is vertically oriented and fed off the roll in a counterclockwise direction. The material passes around a first cylindrical guide block  138  which confines the material between a rear wall  139  of the accumulator  110  and the first cylindrical guide block  138 . Material then passes through a large loop  140  within the accumulator and is subsequently brought back toward the supply roll where it passes around a second cylindrical guide block  142  where its direction is reversed so that it passes across a third cylindrical guide block  144  before being fed through the folding blocks  112 . Within the accumulator, at the downstream end thereof is a vacuum port  145  in an end wall of the accumulator and a pair of vent ports  146  opening through the bottom wall  148  of the accumulator. The vacuum port is connected to a vacuum source (not shown. When vane material is pulled out of the accumulator by the friction rollers  118  and fed downstream, the accumulated strip material within the accumulator is drawn down so that the loop is smaller than illustrated in  FIG. 6 . Once the friction rollers are stopped, however, the vacuum source draws additional material off the supply roll. To prevent the strip material from being drawn over the vacuum port and held in that position by the vacuum, the vents are opened to reduce the vacuum in the downstream end of the accumulator. Depending on the porosity and permeability of the strip material, it is sometimes desirable to further reduce the vacuum so a third vent port is provided at the downstream end of the accumulator with a selectively operable gate to open or close the third vent port. The pull on the strip material by the friction rollers  118  overcomes the vacuum draw on the material until the rollers stop rotating.  
      As seen in  FIGS. 5 and 6 , as the strip material leaves the accumulator  110 , it is fed in its vertical orientation to the folding blocks  112  where it passes sequentially through the folding blocks which have generally C-shaped notches  150  formed in a front edge thereof. The notches become decreasingly shallow from top to bottom from the upstream-most block to the downstream-most block so that the strip material leaving the downstream block is folded substantially in half along the longitudinal crease  92  but with a slight extension along the lower layer on its free edge that defines a flap  152  having the inert bead of adhesive  94  thereon which is subsequently folded over onto the top layer to secure the strip material into a tubular form as will be described later. The folded strip of material is also horizontally oriented upon leaving the folding blocks.  
      In  FIG. 13 , the vane strip material  90  is seen immediately before it enters the most downstream folding block  112  where it can be seen to be of generally flat tubular configuration folded along its longitudinal crease  92  and defining the flap  152  on the lower layer with the elongated inert adhesive bead  94  ( FIGS. 13 and 14 ) thereon.  FIG. 14  is a cross section immediately before the strip material enters the first folding and aligning housing  114  where it will be seen the top and bottom layers of the vane are compressed into a confronting face-to-face flat relationship again with the flap  152  protruding from one side edge in co-planar relationship with the lower layer of the folded material. With reference to  FIG. 8 , a horizontal section shows the apparatus through the first folding and aligning housing, the adjacent friction rollers  118 , the cutter  116 , and subsequently the conveyor belts  130  and  132  used to transfer the cut vane material downstream in the apparatus.  FIG. 7  is a view similar to  FIG. 8  with the vane strip material positioned in the apparatus.  
      The first folding and aligning housing  114  seen in horizontal section in  FIGS. 7 and 8  is shown in sequential vertical sections in  FIGS. 9-12 . The first folding and aligning housing can be seen to include a top component  154  and a complementary bottom component  156  that when mounted on each other define a space therebetween through which the folded vane strip material  90  can slidably pass. The top component as viewed in  FIGS. 9 and 10  can be seen to be of generally T-shaped cross section with a centered downward abutment  158  and a handle  160  for gripping the upper component. The abutment projects downwardly into a generally U-shaped centered channel  162  having a back wall  162   a  in the lower component so as to define a relatively wide space  164  on the front side of the machine or the left side as viewed in  FIGS. 9 and 10 . At the upstream end of the lower component, an inclined ramp or cam surface  166  ( FIG. 9 ) is formed in the lower component so that the flap  152  on the lower layer of the strip material can be urged or folded upwardly, forcing the vane material rearwardly into engaging alignment with the back wall  162   a , until it assumes a somewhat vertical orientation against a vertical side wall  168  in the lower component as viewed in  FIG. 10 . The first folding housing in addition to forcing the strip material into a compressed configuration and aligning the material with the back wall  162   a , also initially folds the flap upwardly so that it can be readily folded over the top layer in a downstream operation to be described later to complete the tubular formation of a vane. In  FIG. 11 , it will be seen that the upper component has a downwardly facing inclined ramp  170  which progressively engages the flap  152  to force it downwardly from its generally vertical orientation of  FIG. 10  toward a flattened configuration assumed at the location in the first folding housing where the section of  FIG. 12  is taken. At that location, the block or abutment  158  in the upper component of the first folding housing has a horizontal bottom wall  172  which has forced the flap downwardly again into a coplanar relationship with the remainder of the lower layer of the folded vane strip material. The vane strip material emanates from the downstream end of the first folding housing in the configuration illustrated in  FIG. 12  and in that configuration it is desirably configured for cutting with the guillotine cutter  116  which operates in a vertical plane. With reference to  FIG. 8 , the cutter can be seen to be positioned between the friction rollers  118  and the downstream conveyor belts  130  and  132  in a gap where the vane is not supported by the friction rollers or the downstream conveyor belt but only by the cutter itself.  
      The cutter  116  is probably best seen in  FIG. 16  where the vertically reciprocal guillotine cutting blade  126  is positioned vertically above a back-up plate  174  and the pneumatic cylinder  128  is provided for activating and deactivating the blade so that it can be advanced downwardly to cut the vane strip material and subsequently retracted in a very quick manner. The friction rollers  118  are seen immediately upstream from the cutter so that vane strip material can be pulled from the accumulator  110 , through the folding blocks  112 , and the first folding housing  114  to be fed into the cutter.  
      As also seen in  FIG. 16 , from the cutter  116 , the cut lengths of vane strip material  90  are advanced downstream by the upper  130  and lower  132  endless belts with the upstream ends of each belt passing over three vertically aligned idler rollers  176  with the middle one of the three idler rollers being immediately adjacent to a driven roller  178 . Immediately downstream from the driven roller is a low friction block  180  across which the upstream directed run of the associated belt  130  or  132  passes to provide more positive traction on the driven roller. Further, the middle one of the three idler rollers is biased toward the drive roller with pneumatic cylinders  182  shown best in  FIG. 15  which are connected with lever arms  184  so that the middle idler is biased into engagement with the associated belt as it passes between the middle idler roller and the drive roller. In this manner, both the upper and lower endless belts are positively driven in a synchronous manner with a suitable pneumatic motor. As will be appreciated in  FIG. 16 , the downstream runs of the upper  130  and lower  132  endless belts are in facing relationship with the folded cut length of vane strip material  90  confined therebetween. When the belts are driven, the vane is therefore carried or advanced downstream toward the panel assembly system  86 . In  FIG. 17 , the back side ends of the driven rollers  178  are seen joined to the drive shaft  186  of the pneumatic drive motor with a timing belt  188  and an idler gear  190  so that both the upper and lower endless belts are driven at the same speed.  
      As seen best in  FIGS. 2B, 3B  and  20 , as the folded cut length of vane strip material  90  is advanced downstream from the cutter  116 , it passes through the adhesive activation station  134 . The vane is not slowed down as it passes through the adhesive activation station inasmuch as infrared heat in the station is adequate to activate the otherwise inert adhesive  94  on the flap  152  of each length of vane strip material during the time period the length of vane strip material is exposed to the heat in the adhesive activation chamber. With reference to  FIG. 20 , the vane strip material protrudes laterally from the endless drive belts  130  and  132  and the adhesive activating chamber is disposed laterally on the forward side of the drive belts so that it can be aligned with the bead of adhesive on the flap of the strip of vane material. A support block  192  is provided for the laterally extending vane strip material and a heat radiating chamber  194  is mounted above the lateral extension of the vane strip material. The heat radiating chamber is an elongated chamber having a reflective panel  196  of generally parabolic transverse cross section which is focused at the location where the bead of adhesive passes through the chamber. An elongated infrared bulb  198  is positioned within the parabolic reflector so that the radiated heat waves therefrom are reflected off the parabolic reflector and downwardly onto the bead of adhesive to concentrate the heat and activate the otherwise inert adhesive. In this manner, when the length of vane strip material emanates from the adhesive activating station, the adhesive is tacky and in a condition where it will bond to another surface. The heat activating station can also be seen in  FIGS. 21 and 22  with  FIG. 21  being an isometric showing the chamber  194  in a laterally positioned offset location from the drive belts and in  FIG. 21  the drive belts and vane strip material are shown within the chamber as illustrated in  FIG. 22 .  
      As probably best seen in  FIGS. 23-30 , upon leaving the adhesive activation station  134 , the strip of material  90  is passed through the second folding housing  136  wherein the flap  152  with the adhesive  94  thereon is folded vertically upwardly and then horizontally over the adjacent edge of the top layer of the folded vane strip material and compressed against the top surface of the folded vane strip material to form a completed tubular vane. The second folding housing comprises a two-piece housing having an upper component  202  and a lower component  204 . With reference to  FIG. 25 , the lower component is a block-like body having an upstream ramp  206  of longitudinally curved configuration which is aligned with the flap  152  of the vane strip material  90  so as to engage the flap and progressively vertically orient the flap as possibly best seen in  FIGS. 26, 27 , and  28 . Immediately downstream from the curved ramp is a second curved downwardly directed ramp  208  which takes the vertically oriented flap and folds it further into a horizontal position overlying the adjacent edge of the upper surface of the vane strip material as probably best seen in  FIGS. 26 and 29 .  
      The upper component  202  of the second folding housing is somewhat complementary with the lower component  204  and allows space between the first curved ramp  206  to allow the flap to be folded and then assists the second curved ramp  208  in folding the flap on over the top surface of the vane strip material. After the flap has been folded over the top surface of the vane strip material so that the adhesive is bonding the flap to the top surface of the vane strip material, the vane strip material passes through spaced confronting faces  210  and  212  respectively of the upper and lower blocks which retain the compressed relationship of the flap with the top surface of the vane strip material.  
      After emanating from the downstream end of the second folding housing  136 , the upper endless belt  130  passes around an idler roller  214  ( FIG. 33 ) and returns upstream so as to lose its engagement with the tubular vanes. The lower endless belt  132  extends further downstream and passes around an idler pulley  215  immediately adjacent and upstream from the panel assembly system  86 . At the location where the idler roller  244  is located, a laterally adjacent pair of upper  216  and lower  218  belts engage the tubular vane at a laterally offset location from where the lower drive belt engages the vane strip material. As will be explained hereafter, the lower belt  218  is driven by a roller  219  on a drive shaft  221  carrying idler roller  215  but the upper belt  216  is simply an idler belt rotated by the lower belt  218  and the vane  124  carried between the belts  216  and  218 . Accordingly, the tubular vane continues to move in a linear path in a downstream direction even though its driving force has at least partially been transferred from one set of endless belts  130  and  132  to a second set  216  and  218 .  
      The second set of endless belts are possibly best seen in  FIGS. 30, 31  and  34 . The lower belt  218  at its downstream extent passes around the drive roller  219  and at its upstream extent tensioning rollers  222  ( FIGS. 30-34 ) to provide a positive grip on the tubular vane  124  for moving it downstream. The upper belt  216  passes around the idler rollers  223  and as mentioned above is driven through its operative engagement with the lower belt  218  and vanes  124  carried therebetween. Immediately after being transferred to the second set of endless belts, the tubular vane  124  is passed through a compression block  225  which maintains compression of the flap  152  on the top surface of a vane  124  and a cooling station  224  where cooling blocks  226  are positioned above and below the endless vanes if necessary. Typically, the cooling occurs naturally but depending upon environmental elements, a cooling system in the blocks  226  may be utilized to make sure the adhesive cures before the vane is passed into the panel-assembly system  86 .  
      The panel-assembly system  86  is best seen in  FIGS. 1, 2A ,  3 A, and  35 - 75 . It will be appreciated the panel-assembly system is mounted on a framework  228  with various tracks to be described hereafter, a series of the cord ladder assemblies  102 , the upstream most of which is fixed and the downstream four of which are slidably movable on tracks in upstream and downstream directions between fixed positions. A lift tower  230  is also provided with lift cords  232  associated with each cord ladder assembly  102  and a motor driven pulley system  234  for raising or lowering the lift cords  232  as will be described hereafter. The panel assembly system further houses a portion of the vane-sizing system  84  mentioned previously in connection with the cutting of the vane strip material to desired predetermined lengths.  
      As possibly best seen in  FIGS. 2A and 37 , the front of the panel assembly system  86  has a generally V-shaped upwardly opening longitudinally extending horizontal channel or trough  236  supported on the framework  228  of the apparatus in a fixed position with a limit bracket  238  extending forwardly off a side panel  240  of the fixed cord ladder assembly  102  in alignment with the V-shaped channel to define an upstream end of the channel. The channel  236  is adapted to releasably receive a tubular template  242  of a configuration similar to that of the tubular vanes  124  and of a length corresponding to the predetermined length desired for the vanes being assembled in a particular panel  100 . The tubular templates are illustrated in  FIG. 38  as being of various lengths with the shortest template having a pair of notches  244  formed in its upper edge and as the length of the templates gets longer, the number of notches may increase. Each notch corresponds with the location on a vane  124  being used in a panel where a cord ladder  98  will be positioned as will be made more clear hereafter.  
      In order to cut the vane strip material  90  at the desired lengths for a panel  100  of a predetermined width, a template  242  as shown in  FIG. 38  of the desired length or a length not less than the width of a panel being fabricated is placed in the V-shaped channel  236 . A template positioning plate  246  possibly seen best in  FIGS. 2A and 41  automatically engages the downstream end of the template and slides it forwardly in the V-shaped groove until it abuts the limit bracket  238  at the upstream end of the V-shaped groove. The positioning plate is horizontally disposed and mounted on a vertical base  245  with the base being mounted on a guide track  247  ( FIG. 41 ) for sliding movement in an upstream or downstream direction. It should also be noted the positioning plate can be moved independently of the cord ladder assemblies  102  and along and past the assemblies if necessary without interference. The positioning plate  246  is connected to a pair of non-extensible but flexible cables  248  and  250  which in turn are connected to the block  122  on which the photosensors or detectors  120  are mounted so that sliding movement of the positioning plate causes a corresponding sliding movement of the block  122  on which the photosensors are mounted. The cable  248  passes through a cable tensioner  251  ( FIGS. 4B and 32 ) to place a desired tension in cable  248  and consequently cable  250  as will be appreciated with the description that follows.  
      The routing of the cables  248  and  250  is probably best seen in  FIG. 4B . The first cable  248  is anchored to a pin  252  on the positioning plate  246  and extends downstream around a first vertically oriented pulley  254 , a second vertically oriented pulley  256  disposed at 90 degrees relative to the first pulley, a third horizontal pulley  258 , and then upstream where it passes around a pair of vertically oriented pulleys  260  immediately downstream from the cutter  116  and from these vertically oriented pulleys it returns to and is secured to the block  122  on which the photosensors  120  are mounted so the cable is capable of pulling the block  122  in an upstream direction. The second cable  250  is also anchored to a pin  252  on the bottom of the positioning plate  246  and extends upstream therefrom, passes around a horizontally oriented pulley  262 , and subsequently a pair of vertically oriented pulleys  264  that are 90 degrees relative to each other from which the cable  250  extends upstream and is anchored to the block  122  on which the photosensors  120  are mounted in a position to pull the block in a downstream direction. The block  122  of course is slidably mounted on a guide rail  266  ( FIG. 18 ) on the frame for the machine and its positioning is therefore controlled by the cables. It will be appreciated that movement of the positioning plate in an upstream direction when pushing the template  242  in an upstream direction pulls on the cable  248  that extends downstream from the positioning plate thereby pulling the block  122  having the photodetectors  120  upstream. Of course, the cable  250  extending upstream from the positioning plate allows upstream movement of the block correspondingly. Movement of the positioning plate downstream, however, has a reverse effect on the block so that the block can be moved downstream. It will therefore be appreciated that as the positioning plate is moved upstream corresponding with shorter lengths of templates, the block  122  is also moved upstream and closer to the cutter  116  so that the length of vane strip material  90  being cut will be commensurate with the shorter length of template. Of course the opposite is true with longer templates used with panels of greater widths.  
      With reference to  FIG. 41 , a pneumatic cylinder  268  is provided with a cable  270  emanating from its upstream and downstream ends with the cable in combination with the cylinder forming an endless loop around horizontally oriented pulleys  272  spaced from opposite ends of the pneumatic cylinder. The cable  270  is anchored to the lower edge of the base  245  of the positioning plate  246  at  249  so that movement of the cable causes the plate to move correspondingly. The control system (not shown) for the apparatus is such that when a template is dropped into the V-shaped channel  236 , the pneumatic cylinder  268  is energized to move the cable in a clockwise direction as viewed in  FIG. 41  thereby moving the positioning plate upstream until the template has been advanced against the limit bracket  238  at which time the pneumatic cylinder is deactivated. In this manner, the positioning plate is automatically controlled to sense the length of a template which information is then transferred via the cables  248  and  250  to the block  122  carrying the photosensors  120  so that the vane strip material  90  is cut to the desired length.  
      With reference to  FIG. 2A , the cord ladder assemblies  102  can be seen to be identical except that the fixed cord ladder assembly, which is the upstream-most assembly  102 , does not have a template detector  274  on its front face  240  as do the movable assemblies  102 . In other words, the fixed assembly always remains in the same position and is utilized regardless of the size of the panel to be fabricated in the apparatus and functions to properly position the most upstream cord ladder  98  used in the panel.  
      The movable cord ladder assemblies  102  are slidable along a track  276  as seen in  FIGS. 37 and 41  which cooperates with slide blocks  278  on the frames of the assemblies  102  to facilitate their movement in upstream and downstream directions. Each movable assembly has a front  240  and rear  280  vertical plate with a template detector being mounted near the bottom of the front plate on each assembly. The template detectors are each identical and probably best seen in  FIGS. 35, 39 , and  40  to include a vertical mounting plate  282  on which a base plate  284  is slidably mounted on a track  286  for movement in upstream or downstream directions. With reference to  FIGS. 39 and 40 , each detector has a horizontal pneumatic cylinder  288  and a vertical pneumatic cylinder  290  with the horizontal cylinder being mounted on the mounting plate  282  and the vertical cylinder on the base plate  284  carried by the plunger of the horizontal cylinder  288 . The vertical cylinder has its plunger connected to the free end of a pivot plate  294  having a catch finger  296  mounted thereon with the catch finger being adapted to be removably engaged in a notch  244  along the top edge of a template  242  as described previously.  
      The detector  274  is utilized to correlate and position a cord ladder assembly  102  relative to a template  242  by moving the assembly along its track  276  until the assembly is approximately aligned with a notch  244  in the template and the horizontal cylinder  288  can then move the block  292  carrying the vertical cylinder until the catch finger  296  is somewhat aligned with the associated notch  244  in the template. The vertical cylinder  290  can then be activated to extend its plunger causing the pivot plate  294  to pivot downwardly forcing the catch finger into the notch. If the alignment is not precise, the horizontal cylinder  288  is activated to move the vertical cylinder upstream or downstream until the lock finger aligns with and is driven into the associated notch by the vertical cylinder. In this manner, the associated lift cord assembly  102  is properly positioned relative to the template  242  and the template position correlates with the position of tubular vanes  124  being assembled in the panel formed by the apparatus. Each movable cord ladder assembly is positioned relative to the template in the same manner so they are distributed and separated from each other corresponding to the notches in the template. If the panel being formed is of a narrow width so that all five of the cord ladder assemblies are not necessary, the unused assemblies can be shifted downstream and out of the way such as seen in  FIGS. 4C, 4E ,  4 F, and  4 G.  
      Looking at  FIGS. 35 and 43 , each fixed and movable cord ladder assembly  102  can be seen to include a step motor-driven wheel  298  on which a supply of cord ladder material  98  is wrapped, a pair of lift towers  300  each carrying an endless lift belt  302  having lift fingers  304  uniformly spaced along its outer circumference, a system for guiding cord ladder material  98  vertically between the endless lift belts, and a device  306  for applying adhesive and drying the adhesive securing each vane  124  to a cord ladder  98 .  
      The cord ladder material  98 , which might be best seen in  FIG. 57 , is conventional and made from flexible cord. The ladder material has a pair of vertical riser cords  308  with horizontal rungs  310  interconnecting the vertical cords at uniformly spaced locations. The rungs are utilized to support slats  124  associated therewith so that in the finished panel fabricated with the apparatus of the present invention, a plurality of cord ladders  98  are incorporated with tubular slats  124  associated with each rung  310  of each ladder.  
      The cord ladder material  98  is supplied by being wrapped around the wheel  298  and is fed upwardly between the lift belts  302  in a manner to be described in detail hereafter. The upper end of the cord ladder material associated with any panel  100  being assembled in the apparatus is connected to a lift hook  312  at the end of one of the lift cables or cords  232  shown best in  FIG. 1 . A lift cable is secured to the top end of each cord ladder  98  with five lift cords being provided even though they may not all be needed depending upon the width of the panel being assembled and the number of cord ladder assemblies being utilized. The opposite end of each lift cable is connected to a spool  314  which can be rotated in either direction by a reversible pneumatic motor  316 . Rotation of the motor in one direction causes the lift cables to be wrapped around the spool at spaced locations along the length of the spool as the panel being assembled increases in size. When the panel is completed, the lift cables are removed from the cord ladders and the assembled panel is thereafter removed from the apparatus.  
      Before assembling a panel  100  in the panel-assembly system, the cord ladders  98  are threaded through the cord-ladder assembly  102  from bottom to top and subsequently connected to a lift hook  312  on an associated lift cable  232 . The cord ladder material is wrapped around the wheel  298  so that the wheel rotates in a counterclockwise direction as viewed in  FIG. 35  as the material is being removed therefrom. In other words, the material is fed off the bottom of the wheel toward a space between the lift belts  302 . Immediately adjacent the wheel  298  and spaced from opposite sides thereof are a pair of vertical channels  318  ( FIG. 57 ) slidably carrying a tensioning spreader spool  320  of generally cylindrical configuration having cylindrical ends  322  adapted to roll within the vertical channels. The tensioning spreader spool is therefore adapted to move vertically but is of a predetermined weight so as to stretch the cord ladder material to place a desired tension thereon as it is being processed through the assembly. The ends of the spool  320  are beveled so as to encourage the vertical runs of the cord ladder passing thereacross to be spread and spaced from each other as possibly best seen in  FIGS. 53 and 55 .  
      Each vertical riser cord  308  of a cord ladder  98  after passing around the spreader spool  320  is threaded through a circular passage  324  ( FIGS. 57 and 60 ) in a riser guide  326  with the circular passage having a very narrow vertical access slot  328  which is slightly smaller than the diameter of the cord but such that the cord can be forced through the slot but will not easily come back out or escape through the slot. In other words, once the vertical cord is positioned within the circular passage, it will remain therein and slidably pass therethrough. The slot also allows the rungs  310 , which are typically of a thinner diameter than the vertical riser cords, to slide therethrough as the lift cord is moved vertically upwardly through the assembly. The riser guides  326  serve to hold the vertical cords in a separated position at this location in the assembly as possibly best seen in  FIG. 57 . After passing through the riser guides, each vertical riser cord is fed into and behind a vertical guide plate  330  which confines the vertical cord behind an associated lift belt  302 .  
      As can be appreciated by reference to  FIGS. 58 and 59 , each lift belt  302  has a notch  332  formed in its forward edge adapted to receive a rung  310  of the cord ladder  98  so that the vertical riser cords  308  can remain behind the belt with the rungs extending between the belts and passing through the notches in the lift belts. As will be described in more detail later, adjacent each notch in the lift belt is a lift finger  304  having a shelf  305  aligned with the notch  332  for supporting an edge of a tubular vane  124  during the assembly process. The inside surface of each belt has sets of engagement pins  334  adapted to cooperate with a driven pulley  336  ( FIG. 57 ) at the bottom of each lift tower and an idler pulley  338  at the top of each lift tower. The driven pulley  336  is engaged with a reversible drive motor (not seen in  FIG. 57 ) so the lift belts can be reversibly rotatably driven.  
      The relationship of the cord ladder  98  to the lift belts  302  is probably best appreciated by reference to  FIGS. 55 and 56  wherein it will be seen the vertical riser cords  308  are positioned behind the lift belts and the rungs  310  extend through the notches  332  in the edges thereof so the cord ladder is retained in a spread condition with each rung in a taut horizontal orientation and spaced from adjacent rungs.  
      With reference to  FIG. 57 , near the top of a lift tower  300 , the cord ladders  98  engage ramp blocks  340  having inclined surfaces  342  for forcing the vertical risers cords  308  of a cord ladder in a downstream direction so it is clear of the lift belts  302  as it moves upwardly toward its connection with the lift cables  232 . As possibly best seen in  FIGS. 35 and 62 , a belt spreader  344  made of a rigid but somewhat resilient material is mounted on the framework of each lift cord assembly  102  with the spreader, as best seen in  FIG. 62 , being of generally U-shaped configuration and having a pair of upwardly directed arms  346  with channels  348  formed in their outer surfaces through which a lift belt  302  and its associated lift fingers  304  can pass. The belt spreader serves, amongst other purposes, as a means for keeping the lift belts in desirably spaced relationship with each other so the cord ladder is also retained in a fully spread position for receipt of tubular vanes  124  as will be described hereafter.  
      The vertical riser cords  308  in each cord ladder  98  are obviously spaced from each other in a lateral direction from the front of the machine to the rear of the machine so that openings  350  ( FIGS. 53 and 54 ) defined between the vertical cords and adjacent rungs are alignable with a passage  352  ( FIG. 34 ) in the framework of the apparatus in an upstream/downstream direction for receipt of previously formed tubular vanes  124 .  
      As will be appreciated, a space is defined between the lift towers  300  and this space is aligned with incoming previously formed tubular vanes  124  at a location immediately above the belt spreader  344 . This might be possibly best appreciated by reference to  FIG. 43  and it will also be appreciated on the upstream side of a cord ladder assembly  102  immediately above the belt spreader, a vane detector  354  is mounted which is seen in detail in  FIG. 61 . The vane detector is of generally U-shaped configuration defining a U-shaped slot  356  therethrough through which a vane can be advanced into the associated cord ladder assembly  102 . The vane detector has a photoelectric cell (not seen) that extends a beam through a passage  358  in the base of the slot so that the presence of a vane can be detected to tell the control computer that a vane has passed at this location.  
      Vanes  124  being advanced by the second set of drive belts  216  and  218  can be fed through a cord ladder assembly  102  but can be stopped adjacent to the last cord ladder assembly being used in the formation of a panel. Of course, the last cord ladder assembly being utilized is determined by the length of the panel being fabricated and the template  242  associated therewith. Each cord ladder assembly has a stop bumper  360  possibly seen best in  FIGS. 44-51  which is alignable with the slot  356  through the vane detector but on the downstream side of the cord ladder assembly. The bumper is mounted on a horizontally slidable plate  362  supported by a horizontal track  364  and movable with a pneumatic cylinder (not shown). With reference to  FIG. 46 , the bumper stop can be fully retracted out of the path of movement of a vane shown in dashed lines or extended into the path of movement of a vane to prevent any further movement in a downstream direction of a vane. Obviously, in the most downstream cord ladder assembly utilized in the assembly of a panel, the stop bumper is extended as shown in  FIG. 47  to terminate any further downstream movement of the vane whereas in any cord ladder assembly upstream from this cord ladder assembly, the bumper stop is retracted so that the vane can pass uninhibited through that assembly.  
      The bumper stop  360  has a bowed spring steel plate  366  vertically oriented in a position to engage the lead end of a tubular vane  124  so that the vane engages the spring steel and is thrown back in an upstream direction after being resiliently absorbed by the spring steel and a pneumatic cylinder  368 . The trailing end of the tubular vane is thereafter moved by the cylinder back into engagement with a spring steel gate  370  ( FIG. 34 ) mounted on a wall of the framework in overlying relationship with the passage  352  through the framework through which the tubular vanes are advanced into the panel assembly system  86 . The spring steel gate  370  is adapted to flex upwardly to allow a vane to pass in a downstream direction but as soon as it is passes the gate, the gate drops back down into a vertical position overlying the passage  352  so that when the vane is resiliently forced back upstream after hitting the spring steel on the bumper stop it will be blocked from any further upstream movement and positively positioned between the two sheets of spring steel. In this manner, the vane is properly positioned in an upstream/downstream location and with each cord ladder assembly  102  positioned along its length at a location where a cord ladder  98  is to be connected to the tubular vane  124 .  
      The passage allowing the tubular slats to be passed into the panel-assembly system is positioned relative to a cord ladder so that as the slat enters the panel-assembly system, it is beneath corresponding rungs  310  of the various cord ladders being used in the panel  100 .  
      As can be appreciated by reference to  FIGS. 65A-65F , which are diagrammatic fragmentary views looking in a downstream direction between the lift towers  300 , the upper ends of the resilient legs  346  of the belt spreader are disposed immediately beneath a pair of aligned lift fingers  304  on the spaced lift belts  302 . The lift fingers have beveled surfaces  371  beneath their shelves  305  with the beveled surfaces inclining upwardly and inwardly toward the opposite lift belt. The upper ends of the resilient arms  346  are seen in  FIG. 65A  to be positioned immediately beneath a pair of lift fingers and in a position so as to be engageable with the beveled surfaces of the lift fingers.  
      Looking at  FIG. 65B , a vane has been shown inserted into the space between the lift belts  302  and in a space within the cord ladders so that a rung  310  of the cord ladder is spaced above and below the vane.  
      As will be clear with the description of the invention hereafter, it is important that the rung  310  above a vane  124  ultimately be positioned in contiguous relationship with the top surface of the vane. In order to desirably position the vane adjacent to its overlying rung, the motor driving the lift belts  302  is reversed so that the lift fingers  304  move downwardly toward the arms  346  of the belt spreader. As seen in  FIG. 65C , as the lift fingers move downwardly with the associated lift belts, the rung above the vane is moved downwardly toward the top surface of the vane and the lift fingers are positioned to engage the upper ends of the arms  346  of the belt spreader. As viewed in  FIG. 65D , further downward movement of the lift belts causes the beveled surface  371  of the associated lift fingers to engage and compress the arms  346  of the belt spreader causing them to pivot inwardly even though they continue to support the vane as the overlying rung is moved downwardly into closely spaced relationship with the top edges of the vane. As seen in  FIG. 65E , when the lift belts have been lowered enough so that the top edges of the arms  346  are substantially coincident with the shelves  305  of the associated lift fingers, the vane supported by the belt spreader is forced into engagement with the overlying rung. It should also be appreciated the vane is positioned above the shelves of the associated lift fingers and will thereafter be supported by the shelves. The drive motor for the lift belts can then be reversed so as to move the belts in an upward direction so that the vane is lifted while engaged with its associated overlying rung and the belt spreader is allowed to resiliently rebound to its rest position with the arms  346  fully spread. The arms will remain fully spread until the next lower pair of lift fingers engage outer beveled surfaces  373  of the arms compressing them inwardly so as to allow the lift fingers to pass over the top of the belt spreader until the apparatus again reaches the position of  FIG. 65A  where it is desirably positioned for receiving the next lower vane. By following the above sequence, vanes  124  are inserted into the cord ladder and desirably positioned in underlying contiguous relationship with a rung of the cord ladder for later processing.  
      The rungs are secured to the top surface of a vane  124  in any suitable manner such as with adhesive, ultrasonic bonding, or the like, but in the disclosed embodiment, the connection is with adhesive. Two dots  371  of adhesive are utilized to secure each rung to the top surface of a vane with each dot being positioned closely adjacent to one edge of the tubular vane. A pair of adhesive application devices  372  as shown in  FIG. 66  are secured to each cord ladder assembly  102  on each lift tower  300  adjacent to a vane positioned in the assembly. The devices  372  are mounted at an angle as seen in  FIG. 35  so as not to interfere with other operative components of the cord ladder assembly.  
      Each adhesive application device  372  is reciprocally mounted on a plate  374  ( FIGS. 35 and 69 B) and movable reciprocally in a horizontal plane by pneumatic cylinders so that the device can be moved into alignment with the vanes for application of adhesive and retracted to allow the vanes to move upwardly within the lift towers  300 .  
      The adhesive application device  372  as seen in  FIGS. 66 and 69 A has a tubular adhesive applicator  378  at a low location thereon supported on framework for the device with the applicator being pivotally mounted and pivoted by a pneumatic cylinder  380  between the inclined position shown in  FIG. 66  and a horizontal position to be described hereafter. Immediately above the adhesive applicator are a pair of superimposed gas and ultraviolet (UV) dryers  382  and  384  with each dryer being positioned so as to be associated with an adjacent vane in the panel formed with the apparatus of the invention.  
      As will be described in more detail hereafter, the adhesive applicator  378  during operation is adapted to be operative on the lowermost one of the lowest three vanes in an assembly  102  while the lower dryer  382  is operative on the next adjacent upper vane and the uppermost dryer  384  is operative on the uppermost one of the three lowest vanes.  
      The operation of the adhesive application device  372  is possibly best illustrated by reference to  FIGS. 69A, 70A , and  71 A with their corresponding isometric views  FIGS. 69B, 70B , and  71 B, respectively. Before describing the operation, however, it is felt beneficial to refer to  FIGS. 72-74  which illustrate the operation of each component of the adhesive application device on an associated vane.  FIG. 72  shows a dot of adhesive  371  being applied through the adhesive applicator to the top surface of the vane  124  at a predetermined location so as to encompass the rung  310  of the cord ladder  98  and adhere it to the underlying tubular vane.  
       FIGS. 73, 73A  and  74  show the operation of a gas and UV dryer  382  or  384  wherein it will be appreciated that within the dryer, a vertical passage  388  is positionable above and in alignment with the dot of adhesive  371  applied to a vane  124  with the applicator as mentioned above. A UV fiberoptic light guide or radiator  389  is positioned in an upper portion of the passage  388  directed at the dot of adhesive. The dryer also has a horizontal channel  390  communicating with the vertical passage immediately beneath the radiator  389  and a reciprocal plunger  392  in the horizontal channel. The plunger is reciprocated with a pneumatic cylinder  393  ( FIGS. 71A  and  71 B). When the plunger is extended as shown in  FIG. 73A , it blocks the UV radiation through the passage but when the plunger is retracted, as shown in  FIG. 73 , it allows the UV radiation on the dot of adhesive. The plunger  392  has a slightly smaller diameter than the channel  390  so as to provide a circumferential space  395  therearound. A rear portion  397  of the channel is of even slightly greater diameter and communicates with a transverse gas delivery conduit  399  ( FIGS. 71A and 74 ) so that a drying gas can be delivered from the delivery conduit into the rear portion  397  of the channel. From the rear portion, the gas travels forwardly through the circumferential space  395  to the vertical passage  388  and from there to the dot of adhesive. A preferred gas utilized is nitrogen which under pressure forces the removal of oxygen from the vicinity of the dot of adhesive and encourages the dot of adhesive to dry in a very clear form so that it is not very visible on the surface of the tubular vane.  
      Again referencing  FIGS. 69A, 70A  and  71 A, in  FIG. 69A , the adhesive application device  372  is shown retracted so that the tubular vanes  124  can be lifted within the lift tower  300  in a step-by-step manner. In  FIG. 69A , the lowermost vane illustrated is the vane most recently inserted into the panel-assembly system  86  and the next adjacent upper vane was the previously inserted vane. Once the lift tower has been indexed or stepped to lift the vanes to the position illustrated in  FIG. 69A , the adhesive application device is advanced forwardly into the position of  FIG. 70A  so that the tip of the adhesive applicator  378  having the nozzle thereon overlies the associated edge of the desired vane and in alignment with a rung  310  of the cord ladder. Immediately after the extension of the adhesive application device, the applicator  378  is pivoted with the pneumatic cylinder into the horizontal orientation of  FIG. 71A  wherein the nozzle of the applicator is immediately adjacent to the surface of the vane adjacent the edge thereof and with the rung of the cord ladder therebeneath so that a dot of adhesive  386  can be applied to the top surface of the vane encapsulating the rung. Immediately after the dot of adhesive has been applied, the applicator is pivoted back to the position of  FIG. 70A  and the application device is retracted to the position of  FIG. 69A  so that the cord ladders can be indexed or stepped upwardly one more notch. As will be appreciated by reference to  FIG. 70A , when the application device is extended, the dryers  382  and  384  are positioned in an overlying relationship with the location where a spot of adhesive was previously applied and is utilized to dry the adhesive. It is found that by drying the adhesive twice during two-stepped intervals of the lifting of the panel  100  in the panel-assembly system, the adhesive can be totally dried while maintaining a desired speed of fabrication. In other words, the lower dryer  382  is the first to dry a dot of adhesive and after the next indexing of the system, the upper dryer  384  completes the drying of the same spot of adhesive so the stepped process can be continued without a long delay at one step for complete drying. As mentioned previously, there are two adhesive application devices  372  in each cord ladder assembly  102  so that two dots of adhesive secure each rung to the top surface of the vane as the panel is being fabricated.  
      After the predetermined number of vanes have been incorporated into the predetermined number of cord ladders as illustrated in  FIG. 3A , the machine is automatically stopped indicating that a panel  100  of a predetermined height and predetermined width has been completed. The cord ladders  98  are then removed from the cable  232  and the entire assembled panel removed from the apparatus and inverted before being connected to a headrail and bottom rail as mentioned previously. If the panel is slightly wider than desired due to the use of templates of predetermined lengths, the ends of the slats can be trimmed to any desirable length in a conventional manner.  
      According to the above description, it will be appreciated a panel  100  of interconnected tubular slats or vane  124  and cord ladders  98  can be assembled in a totally automated in-line system with the apparatus of the present invention and with the panel then being appropriate, after inversion, for incorporation into a Venetian blind by connecting the top of the cord ladders to a control system in a headrail and the bottom to a bottom rail. As previously noted, the various motors utilized in operating the apparatus as described are driven with a pneumatic computer-controlled system, the design and operation of which is believed to be within the skill of those in the art and accordingly a detailed description of the operating system is not deemed necessary.  
      Although the present invention has been described with a certain degree of particularity, it is understood the present disclosure has been made by way of example, and changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.