Abstract:
A covering for an architectural opening includes a panel of material consisting of a first flexible sheet of material on which a second flexible sheet of material is secured along vertically spaced horizontal lines of attachment so that the second sheet of material billows or flexes away from the first sheet of material to define a plurality of vertically superimposed cells. The creases placed in the cells are designed so that as the panel of material is wrapped around a roller, the creases are reinforced to extend the life of the creases and thus the desired billowing effect of the cellular panel of material. Various systems are disclosed for extending and retracting a panel of material as well as for anchoring the top and bottom edges of the panel to a roller in a manner so that they can be easily attached/detached without disassembling the hardware for the covering.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a non-provisional application claiming priority to U.S. provisional application Ser. No. 60/640,015, filed Dec. 30, 2004, the disclosure of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates generally to cellular coverings for architectural openings and particularly those utilizing a panel of material formed from two sheets of fabric that are interconnected along horizontal lines of attachment with one sheet defining expanded but drooped cells off a confronting face of the other sheet. The cells are uniquely creased and interconnected to encourage the cells to retain an expanded form. A system for rolling the shade on a roller is also disclosed which encourages a retention of the expanded cellular form, once the panel is unrolled. A system is further disclosed for attaching the top edge and the bottom edge of a panel of material to rollers so the panel can be easily inverted if desired.  
         [0004]     2. Description of the Relevant Art  
         [0005]     Retractable coverings for architectural openings are in common use and include by way of example venetian blinds, vertical blinds, roll-up shades, cellular shades, and the like. Some cellular shades are transversely collapsible and are raised and lowered similarly to a venetian blind while other collapsible shades are retractable about rollers. An example of the later type disclosed in U.S. Pat. No. 5,603,368 which is of common ownership with the present application.  
         [0006]     Improvements in roll-up cellular shades are continually being made and it is to provide an alternative to conventional roll-up cellular shades that the present invention has been developed.  
       SUMMARY OF THE INVENTION  
       [0007]     The cellular panel of the present invention includes a back-up or support structure such as a sheet of flexible material to which a second sheet is attached along vertically spaced horizontal lines of attachment to define a plurality of vertically spaced horizontally extending expanded cells. The second sheet is creased at two locations to form each cell into a generally D-shaped cross-sectional configuration having a rounded soft-hanging curvature. The creases in the cells encourage the cells to be expanded when the panel of material is extended across all or a portion of an architectural opening. The panel can be retracted by rolling it around a roller at the top or bottom of the architectural opening and the creases in the second sheet of fabric are formed so as to be reinforced by being repeatedly folded consistent with the direction of the creases each time the panel is wrapped around a roller.  
         [0008]     A method of creasing the second sheet of material during the formation of the panel of material is disclosed with the creased sheet of material being formed in a shoe that is divided between heating and cooling components. In the heating component, the fabric is drawn into the desired folded configuration and compressed between the heated confronting shoe component and a cylindrical mandrel to form the creases and then the material is cooled as it is drawn between the mandrel and the cooling component to set the creases.  
         [0009]     Several embodiments for retracting the panel of material about rollers are disclosed with each system folding the panel on a roller in a manner to reinforce the creases formed in the second sheet of material so as to encourage the cellular panel to remain expanded each time the covering is extended.  
         [0010]     A unique system for quickly inverting the panel of material by flip flopping the top and bottom edges of the panel is also shown which could be used with most roll-up coverings.  
         [0011]     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  
       [0012]      FIG. 1  is a fragmentary vertical section taken through a panel of material used in a covering in accordance with the present invention with the panel of material shown in an extended position.  
         [0013]      FIG. 1A  is an isometric of a covering in accordance with the present invention utilizing the panel of material shown in  FIG. 1 .  
         [0014]      FIG. 2  is a vertical diagrammatic section taken through a shoe in which the panel of material shown in  FIG. 1  can be formed.  
         [0015]      FIG. 3  is an enlarged fragmentary vertical section taken through a lower portion of the covering of  FIG. 1A .  
         [0016]      FIG. 4  is an isometric similar to  FIG. 1A  showing a second embodiment of the covering of the present invention.  
         [0017]      FIG. 5  is an isometric looking at the rear of the covering of  FIG. 4 .  
         [0018]      FIG. 5A  is an enlarged section taken along line  5 A- 5 A of  FIG. 5 .  
         [0019]      FIG. 5B  is an enlarged section taken along line  5 B- 5 B of  FIG. 5 .  
         [0020]      FIG. 6  is a fragmentary elevation of a roller in which the top or bottom edge of a panel of flexible material is secured with a semi-rigid strip of material illustrating a method of attachment/detachment.  
         [0021]      FIG. 7  is a section taken along line  7 - 7  of  FIG. 6 .  
         [0022]      FIG. 8  is a bottom plan view illustrating the roller of  FIG. 6 .  
         [0023]      FIG. 9  is a fragmentary vertical diagrammatic section through an alternative system for extending and retracting a flexible panel of material in a top down/bottom up environment with the covering partially extended.  
         [0024]      FIG. 10  is a fragmentary section similar to  FIG. 9  with the covering fully retracted.  
         [0025]      FIG. 11  is a fragmentary section similar to  FIG. 9  with the covering fully extended. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0026]     Referring first to  FIGS. 1 and 1 A, a covering  12  incorporating a panel  14  of cellular material in accordance with the present invention is shown to include a head rail  16 , the panel  14  of cellular material with cells  15  anchored at its top edge to the head rail and at its bottom edge to a bottom roller  20 , a pair of looped lift cords  22 , and an endless drive or control cord  24 .  
         [0027]     As is probably best seen in  FIG. 1 , the panel  14  of cellular material is comprised of a support structure which could be a first sheet  26  of backing or support material and a second sheet  28  of looped and creased material that is secured to the first sheet along vertically spaced horizontal lines of attachment  30  in any suitable manner such as with adhesive, ultrasonic bonding or the like. The sheets of material  26  and  28  can be the same or different and can, by way of example, be a sheer fabric, a translucent material, or even an opaque material. Both sheets of material are flexible with at least the second sheet of material being semi-rigid and creasable. The second sheet has enough rigidity to retain the full expanded shape shown in  FIG. 1 . A suitable fibrous material made with a thermo-forming resin is well suited for at least the second sheet of material with thermoset or thermoplastic resins being acceptable binders for the fibers. The support structure would not necessarily have to be a sheet of material  26  but could be for example, a plurality of vertical cords or micro fibers (not shown) to which the second sheet is attached.  
         [0028]     Each cell  15  constitutes an elongated tube of generally D shaped cross section and with each elongated cell overlying a next adjacent lower cell and being identical therewith. Each cell includes a first inwardly directed or pointed crease  32  along the lower edge of its upper line of attachment  30  and a relatively straight upper segment  34  extending from the first crease to a second outwardly directed or pointed crease  36 . The first segment  34  of the cell which might be referred to as a top wall, slopes downwardly at a small acute angle (e.g. between 5° and 45°) to the second crease. A second segment  38  of the cell which might be referred to as a front wall hangs downwardly in a soft drooping or looped fashion from the second crease in a soft hanging curve and is substantially vertically directed. A third segment  40  or bottom wall of the cell extends from a curved and drooped lower edge  42  of the front wall substantially horizontally and rearwardly to the next lower line of attachment  30 . The bottom wall is of generally S shaped configuration. The outwardly pointed or directed second crease  36  as well as the first crease  32  serve to assist in supporting the cell in the fully expanded configuration illustrated in  FIG. 1 , which of course is facilitated further by the semi-rigid character of the material from which the second sheet  28  is made. By making the second sheet from a thermo-forming resin material in which fibers are imbedded, the sheet is resilient in that even after having been deformed as when the material is wrapped around a roller, it will return dependably to the form or configuration shown in  FIG. 1 . This is particularly true, due to the nature in which the material is wrapped around the bottom roller  20 , as will be described in more detail hereafter.  
         [0029]     The panel  14  can be formed in numerous ways, but it has been found desirable to make the panel by first securing the second sheet of material  28  to the first sheet of material  26  along the lines of attachment  30  so the second sheet of material is looped off a front face of the first sheet of material i.e., there is more of the second sheet of material between lines of attachment than of the first sheet of material. The double-layered panel can then be pulled around a mandrel  44  ( FIG. 2 ) beneath a pair of generally semi-cylindrical compressive shoes  46  and  48  which are yieldingly forced against the opposed faces of the mandrel with coil springs  50 . One shoe  46  is heated in a conventional manner such as with a hot fluid passed through internal passages  52  in the shoe while the other shoe  48  is cooled as with a cooling fluid passed through passages  52  in the shoe.  
         [0030]     When the panel of material  14  is pulled into the space between the mandrel  44  and the compressive shoes  46  and  48  as shown in  FIG. 2 , the first sheet of material  26  passes smoothly around the mandrel in a counterclockwise direction while the second sheet of material  28  is laid smoothly against the first sheet of material from a first line of attachment  30  downwardly but as the panel is advanced around the mandrel, the second sheet of material is continuously forced into a smaller and smaller loop until it defines the two creases  32  and  36  and an overlapped fold  54  of generally S-shaped configuration. The overlapped fold is confined between the mandrel and the compressive shoes with the heated shoe forming the creases in the material along the overlapped fold and the cooling shoe setting the creases before the panel of material exits the mandrel. The fold  54  defines overlapping layers of the second sheet of material which includes a line of attachment  30  in the top wall  34  and a top portion of the front wall  38  of a cell  15 . The creases surge the second sheet of material to expand or billow away from the first sheet of material to establish the desired D-shape of the cell as shown in  FIG. 1 . The first crease  32  is secured to the first sheet of material  26  while the second crease  36  is allowed to billow or flex away from the first crease along the first segment or top wall  34  of the cell again as fully appreciated by reference to  FIG. 1 .  
         [0031]     Referring to  FIGS. 1A and 3 , it will be appreciated the panel of material  14  is secured along an upper edge  56  in a fixed relationship and in any suitable manner to the head rail  16 . Preferably the upper edge is concealed within the head rail for aesthetic purposes. The bottom edge  58  of the panel  14  is anchored to the bottom roller  20  of the covering, which is generally cylindrical in configuration, having a longitudinal channel  60  formed in an outer surface thereof defining a relatively small slot  62  in the outer surface between a pair of opposed lips  64 . The lower edge of the panel is hemmed and a rigid or semi-rigid anchor strip  66  is positioned within the hem. The anchor strip with the hem may be slid axially along the length of the roller  20  from one end to the other to secure the lower hemmed edge of the panel to the bottom roller in a conventional manner. The bottom edge could also be secured to the roller in an alternative manner as will be described hereafter.  
         [0032]     The bottom roller  20  is rolled in a counterclockwise direction as viewed in  FIG. 3  when retracting the covering from the extended position of  FIG. 1A  to a fully retracted position wherein the bottom roller is disposed adjacent to the head rail  16 . The bottom roller is rolled with the looped lift cords  22  which are anchored at a front end  68  ( FIG. 1A ) to a concealed location at the front of the head rail and at a back end  70  to a take-up roller  72  in the head rail. The take-up roller is rotated with the endless control cord  24  by moving the control cord in a rotating direction to thereby correspondingly rotate the take-up roller allowing the lift cords  22  to be wrapped therearound. In this manner, the size of the loop of the lift cords is adjustable from a maximum size when the shade is fully extended as shown in  FIG. 1A , to a minimum size when the covering is fully retracted. The rotation of the bottom roller occurs through friction between the lift cords and the panel of material  14  with the lift cords engaging the panel of material around the underside of the bottom roller  20 . As the lift cords are raised along the back of the panel, the shortening of the loop of lift cords causes the bottom roller to be raised while it is being rotated in a counterclockwise direction thereby wrapping the panel of material thereabout. This type of lift system is common in bamboo shades wherein horizontal slats of bamboo are interconnected with elongated vertical cords and the bottom rail is raised with endless lift cords as described above.  
         [0033]     As is best illustrated in  FIG. 3 , as the bottom roller  20  is rotated in a counterclockwise direction, the panel of material  14  is wrapped therearound with the second crease  36  in the panel being encouraged from the configuration of the panel to overlap and form a fold  74  configured identically to the fold  54  in the material as it exits the compressive shoes  46  and  48  as shown in  FIG. 2 . The second sheet of material  28  in the panel is compressed by the lift cords  22  as the panel is initially wrapped onto the bottom roller. The free-hanging soft loop in the front wall  38  of each cell  15  in the second sheet of material adjacent to the bottom of each cell is also forced to fold at  76  in an opposite direction to the second crease  36  and toward an overlying relationship with the preceding or underlying line of attachment  30 . Accordingly, as seen in  FIG. 3 , there are two folds  74  and  76  established as the panel of material wraps around the bottom roller with the folds being directed toward each other and in overlying relationship with a line of attachment  30 .  
         [0034]     As will be appreciated, inasmuch as the first and second creases  32  and  36  are compressed into their original configuration shown in  FIG. 2  as they are wrapped around the bottom roller in the fold  74 , the creases are reinforced each time the panel of material is wrapped around the roller. In this manner, the creases in the second sheet of material are reinforced continually upon operation of the covering encouraging the second sheet to fully deploy to the expanded position shown in  FIG. 1  with repeated use and over long periods of time.  
         [0035]     As will be appreciated, the upper edge  56  of the panel of material  14 , which is secured to the head rail  16 , could be secured to an upper roller (not shown) which is not rotatable but rather statically positioned within the head rail but wherein the upper edge is secured to that roller identically to the manner in which it is secured to the bottom roller  20 , i.e. with a hem and a rigid or semi-rigid anchor strip inserted within the outwardly opening channel  60  of the roller. This system for anchoring the upper edge of the fabric is useful in accordance with features of the present invention which will be described in more detail hereafter.  
         [0036]      FIGS. 4-5B  show an alternative embodiment of the present invention wherein the panel of material  14  is identical to that previously described and wherein the upper edge  56  of the panel of material is secured as with adhesive or the like to the head rail  16  and the bottom edge  58  is secured to the bottom roller  20  in a manner identically to that previously described. In this embodiment of the invention, however, the lift cords have been replaced with lift straps  78  at opposite ends of the panel  14  with the front end  80  of each lift strap being secured preferably in a confined location to the head rail and a rear end  82  of the lift strap being anchored to a spool  84  fixed for unitary rotation with a take-up rod  86 . The take-up rod is supported by a pair of brackets  88  fixed to the head rail and is rotated with an endless control cord  24  with the upper end of the endless control cord  24  being confined within a housing  90  and frictionally engaged with the take-up rod for unitary rotation therewith. In other words, as the control cord is rotated, the take-up rod is simultaneously rotated along with the spools anchoring the rear ends of the lift straps  78 .  
         [0037]     A pair of guide straps  92  have their upper ends  94  secured to the take-up rod  86  and their lower ends  96  secured to a guide rod  98 . The guide rod as shown in  FIG. 5A  has a slot  100  at each end thereof which slidably receives an associated lift strap  78  and a second slot  102  spaced inwardly thereof for anchoring the lower end of an associated guide strap  92 . As seen in  FIG. 5B , the lower ends  104  of the guide straps are hemmed and a rigid rod  106  is inserted therethrough and seated in a recess  108  communicating with the associated slot  102 .  
         [0038]     As the take-up rod is rotated with the control cord  24 , the guide straps  92  are wrapped around the take-up rod  86  on a smaller diameter than the lift straps  78  so that the guide straps will lift the guide rod  98  at about the same speed as the bottom roller  20  is being raised by the lift straps inasmuch as the lift straps pass around a greater and increasing diameter of the bottom roller as the panel of material accumulates thereon. The guide rod therefore retains the position of the lift straps as the covering is moved between retracted and extended positions.  
         [0039]     With reference to  FIGS. 6-8 , a system is shown for easily connecting and/or disconnecting a hemmed edge  110  of a panel of material  112  to/or from an elongated element such as a roller  114  of the type described previously. The panel could be any flexible panel including a panel  14  of the type previously described herein. The roller as seen in  FIG. 7  is of cylindrical configuration having a channel  116  formed therein that opens through a slot  118  in the outer surface of the roller between a pair of confronting lips  120 . The confronting lips are uniformly spaced from each other commencing at each end of the cylinder. However, at a centered location along the length of the cylinder, the lips are retracted as shown in  FIG. 8  to define a relatively wide gap  122 . The wide gap at the longitudinal center of the cylinder or roller  114  is wide enough to allow an anchor strip  124  of semi-rigid material to be removed therefrom while the anchor strip is inserted into the hem  110  along the edge of the panel. When attaching the panel of material  112  to the roller  114 , rather than inserting the hem along with the anchor strip into an open end of the channel and sliding the strip along with the hemmed material therealong as is conventional, the ends of the anchor strip  124  with the hem of the panel therearound can be inserted into the gap  122  and forced in opposite directions until the entire anchor strip has been received with the hemmed edge of the material within the channel  116 . The hemmed edge of the material can be removed in a reverse manner by grasping the anchor strip with the hemmed material at the location of the wide gap and pulling the semi-rigid strip of anchor material out of the channel as illustrated in  FIG. 6 .  
         [0040]     This system for connecting and disconnecting a panel of material  112  to/or from a roller  114  is useful with any flexible panel of material as the material can be removed from the roller without removing the roller from the hardware of the covering in which it is mounted since the anchor strip does not have to be slid longitudinally out of an open end of the roller but can be removed laterally. This also enables one to easily invert a panel of material should the panel lose its resilience and desired cellular configuration in the case with a cellular panel. The resilience of the panel, of course, permits the cells in the panel to fully expand as desired and as illustrated for example in  FIG. 1 . In other words, should the material start drooping more than desired, it can be inverted by easily removing the opposite top and bottom edges of the panel from their anchor rollers and after inverting the panel of material reattaching the edges to the opposite anchor rollers as described above without disassembling the hardware for the covering.  
         [0041]     As can be appreciated by reference to  FIG. 4 , the location where the lift straps  78  or in the case of the embodiment of  FIG. 1A  the lift cords  22 , engage the panel of material  14 , the panel can become deformed at  126 . To avoid such a deformation in the panel, a system of the type shown in  FIGS. 9-11  can be utilized. In this embodiment of the invention, the bottom edge  58  of the panel of material is again secured to the bottom roller  20  as described previously so that the panel of material can be wrapped around the bottom roller as the roller is raised and rotated with the lift cords  22  or straps  78 . For purposes of the present disclosure, lift cords are utilized but lift straps could be used in lieu of the lift cords. In the embodiment of  FIGS. 9-11  and as best appreciated by reference to  FIG. 9 , there is an upper lift cord  22 U and a lower lift cord  22 L with the bottom edge  128  of the upper lift cord being secured to the upper edge of an elongated sling or flexible strip of material  130  with a batten  132  that runs along the full length of the strip of material. Similarly, the upper end  134  of the lower lift cord  22 L is secured to a batten  136  along the bottom edge of the sling of flexible material  130 . The upper lift cord  22 U extends around a pulley  138  in the head rail  140  with the lower lift cord  22 L extending around a pulley  142  disposed beneath and at a rearwardly displaced position in the head rail relative to the pulley  138 . Both the upper and lower lift cords can be manually pulled or released and conventional cleats (not shown) are provided for anchoring the lift cords at any desired location along their length. The panel of covering material  14  has an upper edge  144  adhesively or otherwise secured to the lower cord  22 L immediately beneath the batten  136  as seen in  FIG. 9  with an anchor bar  146  and the lower or opposite edge of the panel is anchored to the bottom roller  20 , for example, in a manner as previously described herein.  
         [0042]     When operating the covering so that the panel of material  14  lowers from the head rail  140  as it is being extended across an architectural opening, the upper lift cord  22 U is raised to its fullest extent and cleated or anchored in a fixed position as shown in  FIG. 1 D  and the lower lift cord  22 L is allowed to extend so that the panel of material is unrolled from the bottom roller  20  which rotates in a clockwise direction allowing the panel of material to be unwrapped therefrom. Of course, the panel can be fully extended in this manner so as to extend from the lower edge of the sling of flexible material  130  down to its bottom edge which is anchored to the bottom roller. Further, leaving the upper lift cord anchored and shortening the lower lift cord will cause the panel to roll up about the bottom roller to raise the shade to the retracted position of  FIG. 1D  adjacent to the head rail. As will be appreciated, by raising the panel of material in this manner, the roller will ultimately become horizontally aligned with the sling  130  and as fully appreciated by reference to  FIG. 10 , the sling will pass beneath the roller and thereby support the roller in the fully retracted position along its full length thereby not deforming the panel  14  as might incur in the embodiments of  FIGS. 1A and 4 .  
         [0043]     The covering of  FIG. 9-11  could also be operated by extending both the upper  22 U and lower  22 L cords with the panel  14  wrapped around the bottom roller  20  and supported by the sling  130  until the bottom roller is positioned adjacent to the lower edge of the architectural opening in which the covering is mounted as shown in  FIG. 11 . By then lowering the lower cord at a rate simultaneous to that of raising the upper lift cord, the panel will unroll from the bottom roller while the bottom roller remains adjacent to the bottom edge of the architectural opening. Accordingly, the panel of material will extend from the bottom of the opening toward the top of the opening. Of course, the reverse would be applicable to lower the top edge of the panel back to a rolled position about the bottom roller at its lowered location. This would be accomplished by raising the bottom lift cord at the same rate that the upper lift cord is extended.  
         [0044]     It will be appreciated that the sling of flexible material  130  can support the bottom roller  20  at any position of the bottom roller by appropriately manipulating the upper  22 U and lower  22 L lift cords and the sling of material, of course, uniformly supports the roller and panel  14  along its entire length to avoid deformation of the roll of panel material. It should also be appreciated that while the embodiment of the invention shown in  FIGS. 9-11  could be used with a panel of material  14  of the type shown in  FIGS. 1 and 1 A, it can also be used with any flexible panel of material capable of being rolled around a roller.  
         [0045]     Although the present invention has been described with a certain degree of particularity, it is understood the 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.