Patent Publication Number: US-10309138-B2

Title: Adjustable path guide for movable partition assemblies

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/626,053, filed Jun. 16, 2017. The entire contents of U.S. patent application Ser. No. 15/626,053 are incorporated by reference. 
    
    
     BACKGROUND 
     The present disclosure relates to fenestration systems. Specifically, to movable partition assemblies using multi-path overhead guide rails. 
     Movable partition assemblies can be found in a wide-range of applications. For example, movable room partitions, sliding closet doors, sliding glass door panels, glazed terrace doors, and store front openings. Movable partition assemblies can include one or more overhead rails that guide the movement of movable panels. The movable panels can be suspended by wheeled trolleys, vertical or horizontal rollers, helical bearings, or other operable carriers. 
     With some movable partition assemblies, the movable panels slide along an overhead linear track, or overhead guide rails, that extend the width of the fenestration opening. For example, for a sliding glass door, glass door panels can be suspended by operable carriers on an overhead guide rail that extends the width of the door opening. The glass door panels can be arranged along parallel paths on the overhead guide rail so that one glass door panel slides behind the other. With this arrangement, the door opening can remain partially impeded because the glass door panels slide behind one another and remain within the door opening. 
     In some commercial and residential applications, it may be desirable to move the movable panels completely outside the door opening. For example, a commercial entrance to a department store within a shopping mall, or a wide terrace door opening in a residential home or apartment. One way that this has been done is by splitting or branching the overhead rails into multiple paths and then diverting the movable panels or a portion of the movable panels along one of the branched overhead rails. This allows the movable panels to be moved and arranged in more sophisticated ways than a single linear overhead rail. For example, in some arrangements, the movable panels can be stacked one behind another outside the door opening. Some movable partition assemblies with two or more movable panels are designed so one side of the movable panel can be diverted to one overhead rail while the other side of the movable panel is diverted to a different overhead rail. For example, a glass door panel system with multi-path overhead rails can be configured to divert each glass door panels from a single overhead rail to a pair of parallel overhead rails with each side of each glass door panel moving along different rails. 
     Various schemes have been devised to selectively divert movable panels from one overhead guide rail to another. Some of these include using path diverters or path guides that divert some operable carriers but not others. 
     SUMMARY 
     The inventor observed that sliding movable panels, especially heavy glass door panels, can be difficult to move around the juncture between one overhead guide rail and another. This can cause challenges at any transition angle, and can be particularly difficult at steeper angles, for example right-angle junctures. The inventor discovered that he could create a much smoother transition at junctures between one overhead rail and another by creating path guides, or diverters, that include leading and trailing running surfaces (i.e. leading and trailing roller guide engaging surfaces) that are parallel to the length-wise axis of their respective overhead rails and that engage self-centering guide rollers along paths tangent to the edge of the guide rollers. This minimizes the resistance to movement typically encountered in other overhead rail systems. In addition, to further minimize resistance, the leading edge of the leading running surface can be radiused or tapered to gently guide the self-centering roller guide back to center. 
     The path guide could include a main body positioned at least in part within the leading overhead rail (i.e. the first rail). The leading running surface (i.e. first running surface), can be formed at the edge of a first projection that projects away from the main body and into the junction between the first rail and the trailing rail (i.e. second rail). The trailing running surface (i.e. second running surface) can be formed directly at an edge of the main body that projects into the junction with a radiused junction forming a smooth radius between the first running surface and the second running surface. 
     The inventor discovered that he could further enhance the smooth movement of the movable panels at the juncture between overhead rails by having the trailing running surface project into the second overhead rail (i.e. the trailing overhead rail). This would be particularly helpful at steep transitions, for example, at or near right-angles. Here, a second projection projects from the main body into the second overhead rail. The second running surface is formed along an inward facing edge of the second projection. This arrangement, gives the roller guide and operable carrier a longer transition length and helps provide for a smoother transition. 
     To account for tolerances between the junction of one overhead rail and another, the main body is captive and slides within the first rail. This adjusts the distance of the second running surface from the length-wise axis of the second overhead rail. This allows the second running surface to be positioned tangent to the outer circumference to the roller guide. This is particularly helpful where the overhead rails are assembled by cutting and welding, which can create tolerance issues and variations at the rail junctures. 
     The inventor envisions that the movable panels of his movable partition system can be any movable partitions such as solid wood panels, infill panels, or glazed infill panels. In addition, the inventor envisions that his movable partitions can be sliding, slidable folding partitions, or a combination of sliding and slidable folding partitions. For example, sliding folding panels can fold, and latch together by a door catch, door latch, or other latching device and then slide together as a single folded unit. In addition, the inventor envisions his movable partition system to include a path guide at each rail-to-rail juncture or alternative path guides only at select rail-to-rail junctures. For example, for a given pair of junctures there could be a path guide only at a first juncture (for example the first juncture encountered by the movable partition), only at the second juncture, or at both junctures. The inventor envisions that his movable partition system could include a multi-path overhead guide rails in combination with bottom guide rails or multi-path overhead guide rails. One of the advantages of the inventor&#39;s movable partition system is that the bottom guide rail is optional. The overhead guide rails in combination with the inventor&#39;s novel path guides can allow the movable partition to move smoothly without the need of a bottom rail guide system. 
     This Summary introduces a selection of concepts in simplified form that are described in the Description. The Summary is not intended to identify essential features or limit the scope of the claimed subject matter. 
    
    
     
       DRAWINGS 
         FIG. 1  illustrates a top plan view of a movable partition system of the present disclosure with the movable panels in the closed position. 
         FIG. 2  illustrates the top plan view of  FIG. 1  with the movable panels positioned between closed and open. 
         FIG. 3  illustrates the top plan view of  FIG. 1  with the movable panels in the open position outside of the fenestration opening. 
         FIG. 4  illustrates a front elevation view of  FIG. 1  taken along lines  4 - 4 . 
         FIG. 5  illustrates an enlarged view of the top of a movable panel of  FIG. 4  showing the movable carriers attached to the top rail of the sash. 
         FIG. 6  illustrates an enlarged view of a portion of  FIG. 1  showing a first path guide. 
         FIG. 7  illustrates an enlarged view of a portion of  FIG. 1  showing a second path guide. 
         FIG. 8  illustrates a section view of  FIG. 4  taken along section lines  8 - 8 . 
         FIG. 9  illustrates a portion of the movable partition system of  FIG. 1  in top and front perspective view and in partial front-cutaway. 
         FIG. 10  illustrates the portion of the movable partition system of  FIG. 9  in top and front perspective view and in top-cutaway. 
         FIG. 11  illustrates a portion of the movable partition system of  FIG. 1  in top and front perspective view and in partial front-cutaway. 
         FIG. 12  illustrates the portion of the movable partition system shown in  FIG. 9  in top and front perspective view and in top-cutaway. 
         FIG. 13  illustrates, in top plan view, a movable partition system of the present disclosure with a combination of overhead rails and with a slidable folding panel assembly in the closed position. 
         FIG. 14  illustrates, in top plan view, the movable partition system of  FIG. 13  with one movable panel opening inwardly, and another movable panel opening outwardly. 
         FIG. 15  illustrates, in top plan view, the slidable folding panel assembly of  FIG. 14  in greater detail. 
         FIG. 16  illustrates an enlarged view of a top portion of the slidable folding panel assembly of  FIG. 13  showing the movable carriers attached to the top rail of center movable panel. 
         FIG. 17  illustrates, in top plan view, the movable panels of  FIG. 13  folded and optionally latched. 
         FIG. 18  illustrates an enlarged view of a portion of  FIG. 16  showing the first path guide at the juncture of two overhead rails. 
         FIG. 19  illustrates, in top plan view, the movable partition system of  FIG. 13  with the movable panels slid so that an operable carrier attached to the center panel engages the path guide. 
         FIG. 20  illustrates, in top plan view, the movable partition system of  FIG. 13  with the movable panels sliding along both two of the overhead rails. 
         FIG. 21  illustrates, in top plan view, movable panels moved to their fully open position. 
         FIG. 22  illustrates, in side view along view lines  22 - 22 , an upper portion the slidable folding panel assembly of  FIG. 17  showing the option showing optional door catches. 
         FIG. 23  illustrates, in top plan view, an optional bottom rail system using a path guide of the present disclosure with the movable panel removed for clarity. 
         FIG. 24  illustrates, in perspective view, an optional bottom rail system using the path guide of the  FIG. 23 . 
     
    
    
     DESCRIPTION 
     The terms “left,” “right,” “top, “bottom,” “upper,” “lower,” “front,” “back,” and “side,” are relative terms used throughout the to help the reader understand the figures. Unless otherwise indicated, these do not denote absolute direction or orientation and do not imply a particular preference. When describing the figures, the terms “top,” “bottom,” “front,” “rear,” and “side,” are from the perspective of outside of the opening looking in. Specific dimensions are intended to help the reader understand the scale and advantage of the disclosed material. Dimensions given are typical and the claimed invention is not limited to the recited dimensions. 
     The following description is made with reference to figures, where like numerals refer to like elements throughout the several views,  FIG. 1  illustrates a top plan view of a movable partition system  10  of the present disclosure with the movable panels  11  in the closed position within the fenestration opening  13 .  FIG. 2  illustrates the top plan view of the movable partition system  10  of  FIG. 1  with the movable panels  11  positioned mid-way between opened and closed.  FIG. 3  illustrates the top plan view of the movable partition system  10  of  FIG. 1  with the movable panels  11  in the open position positioned behind the wall  15  and outside of the fenestration opening  13 .  FIG. 4  illustrates a front elevation view of the movable partition system  10  taken along section lines  4 - 4  from  FIG. 1  and showing the movable panels  11  and operable carriers  17 ,  19  extending upward from the movable panels  11 . The movable panels  11  can be any movable partitions such as solid wood panels, infill panels, or glazed infill panels. For example, sliding glass doors, sliding non-glazed doors, sliding windows, curtain walls, exterior partitions, interior partitions, folding glass doors, folding non-glazed doors, or folding windows. Alternatively, a combination sliding and folding glass door assembly, window assembly, or curtain wall assembly, sliding and folding non-glazed partitions such as wood, metal partitions and the like. For simplicity, the infill panels illustrated throughout this disclosure are illustrated as glazed infill panels. 
     Referring to  FIGS. 1-3 , the movable panels  11  guided by path guides  12 ,  14 ,  16 ,  18  as they slide along overhead rails  21 ,  23 ,  25 ,  27 ,  29 ,  31  by the operable carriers  17 ,  19 . Overhead rail  21  is illustrated positioned between vertical jambs  33  on opposing ends of the fenestration opening  13 . Overhead rail  23  is illustrated positioned parallel to overhead rail  21  on one side of the fenestration opening  13  and extending behind one side of the wall  15 . Overhead rails  25 ,  27  join the overhead rail  21 ,  23  to each other with overhead rails  25 ,  27  positioned parallel to each other and spaced to allow the movable panels  11  to travel between overhead rails  25 ,  27  via the operable carriers  17 ,  19 . Overhead rail  23  is joined to overhead rails  29 ,  31  with overhead rails  29 ,  31  spaced and parallel to each other so that the movable panels  11  can travel along overhead rails  29 ,  31  as shown in  FIGS. 2 and 3 . 
     Referring to  FIG. 4 , the movable panels  11  are illustrated with an infill panel  35 , such as a glass panel, surrounded by sash  37 . The sash  37  can include a top rail  37   a , vertical stiles  37   b ,  37   c , and a bottom rail  37   d  surrounding the infill panel  35 . Alternatively, the movable panels  11  can be solid wood, or any other material suitable for the particular application. For example, in some applications where the fenestration opening  13  of  FIGS. 1-3  go from an exterior environment to an interior environment, the construction of the movable panels  11  and the vertical jambs  33  surrounding the fenestration opening  13  should be suitable for this purpose. In  FIG. 4 , the overhead rail  21  together with the vertical jambs  33  form the fenestration frame. As further illustrated in  FIG. 8 , the overhead rail  21  can be surrounded by a cover  38  to create a unified appearance with the vertical jambs  33 . Referring back to  FIG. 4 , the operable carriers  17 ,  19  are shown projecting out of the top rail  37   a . The operable carriers  17 ,  19  are shown spaced apart and positioned near vertical stiles  37   b ,  37   c  on opposite sides of the infill panel  35 . The operable carriers  17 ,  19  are illustrated in broken line to represent that they are hidden within the overhead rail  21 . 
       FIG. 5  illustrates an enlarged view of the top of the movable panel  11  of  FIG. 4  showing the operable carriers  17 ,  19  attached to the top rail  37   a . The position of the operable carriers  17 ,  19  are shown in relation to the vertical stiles  37   b ,  37   c . The operable carrier  17  is shown proximate to vertical stile  37   b  and the operable carrier  19  is shown positioned proximate to the vertical stile  37   c . Mounting the operable carriers  17 ,  19  wide apart, as illustrated helps distribute the weight of the movable panel  11 , which can be quite significant, especially when the infill panel  35  is a double pane or triple pane glass or other insulated glazing unit (IGU). The operable carriers  17 ,  19  can be identically constructed, as illustrated, with the difference being the position of guide roller  39 . 
     Referring to  FIGS. 2 and 5 , the guide roller  39  ( FIG. 5 ) is positioned on the operable carrier  19  so it passes under path guides  12 ,  14  ( FIG. 2 ) unimpeded, while being guided by path guides  16 ,  18  ( FIG. 2 ). The guide roller  39  ( FIG. 5 ) extends upward from operable carrier  17  and is positioned so it is guided by path guides  12  ( FIG. 2 ) on overhead rail  21  ( FIG. 2 ) and is guided by path guide  14  ( FIG. 2 ) on overhead rail  23  ( FIG. 2 ). Note that in order for the path guides  12 ,  14 ,  16 ,  18  ( FIG. 2 ) to work in combination with operable carriers  17 ,  19  as described, path guide  12  ( FIG. 2 ) and path guide  14  ( FIG. 2 ) can be identical except for thickness, i.e. path guide  16  ( FIG. 2 ) would be thicker than path guide  12  ( FIG. 2 ). Similarly, path guide  18  ( FIG. 2 ) would be thicker than path guide  14  ( FIG. 2 ). Path guides  16 ,  18  ( FIG. 2 ) would have sufficient thickness compared with path guides  12 ,  14  ( FIG. 2 ) to catch and direct their guide rollers  39  ( FIG. 5 ).  FIGS. 9 and 10  illustrate path guide  12  and path guide  16  have different thickness in order to accommodate the height of the guide roller  39  of operable carrier  19 . Similarly,  FIGS. 11 and 12  illustrate path guide  14  and path guide  18  have different thickness in order to accommodate the height of guide roller  39  of operable carrier  19 . 
     The inventor observed that sliding the movable panels  11 , especially heavy glass door panels, can be difficult at the junctures between one overhead rail and another. This can cause particular challenges at right-angle or approximately right-angle junctures, for, example, at the juncture between overhead rail  21  and overhead rail  25  or between overhead rail  21  and overhead rail  27  as illustrated in  FIGS. 1-3 . The inventor discovered that he could create a much smoother transition at junctures between one overhead rail and another by creating path guides, such as path guides  12 ,  14 ,  16 ,  18  that include leading and trailing running surfaces (i.e. leading and trailing guide roller engaging surfaces) that engage self-centering guide rollers, such the guide rollers  39 , along paths tangent to the edge of the guide rollers  39 . This minimizes the resistance to movement encountered in other path guides. In addition, to further minimize resistance, the leading edge of the leading running surface can be radiused or tapered to gently guide the self-centering roller guide back to center. This principle will be described in more detail in the discussion of  FIGS. 6-8 . 
       FIG. 6  illustrates an enlarged view of a portion of  FIG. 1 , taken at detail  6  and showing path guide  12  in detail within the junction of overhead rails  21  and overhead rails  25 . The path guide  12  includes a main body  12   a , a first projection  12   b , a second projection  12   c , a leading edge  12   d  of the first projection  12   b , a first running surface  12   e , a second running surface  12   f , a radiused junction  12   g  between the first running surface  12   e  and the second running surface  12   f , and a slot  12   h  in the main body  12   a . The path guide  12  can be secured to the overhead rail  21  by a combination of a threaded fastener  40  through the overhead rail top  21   e  of  FIG. 8  and through the slot  12   h . The threaded fastener  40  can be a screw, bolt, combination of a screw or bolt and nut, or any threaded fastener suitable for adjustably and removably securing the path guide  12  to the overhead rail  21 . The main body  12   a  can be substantially rectangular, or alternatively have a pair of parallel length-wise edges, so its position can be constrained to be slidably move length-wise along the overhead rail  21 . As illustrated in  FIG. 8 , the rectangular shape of the main body  12   a  in combination with the slotted surface  21   f  on the inside upper portion of the overhead rail  21  can be constructed to constrain movement of the main body  12   a  to only slide longitudinally along the slotted surface  21   f . A perspective view of the path guide  12  along with the leading edge  12   d , the first running surface  12   e , the second running surface  12   f , the radiused junction  12   g , and the slot  12   h  is illustrated in  FIG. 10 . In addition, the path guide  16 , which is substantially identical to the path guide  12  except for thickness, along with the leading edge  16   d , the first running surface  16   e , the second running surface  16   f , the radiused junction  16   g , and the slot  16   h  is also illustrated in  FIG. 10 . 
     Referring to  FIG. 6 , the first projection  12   b  projects from the main body  12   a  length-wise along the overhead rail  21  and into the juncture between the overhead rails  21 ,  25 . The first running surface  12   e  is formed along the inside edge of the first projection  12   b  and can run longitudinally along the overhead rail  21  parallel to the length-wise center line of the overhead rail  21 . The second projection  12   c  can project from the main body  12   a  longitudinally (i.e. length-wise) into the overhead rail  25  from the juncture between the overhead rails  21 ,  25 . The second running surface  12   f  is formed along the inside edge of the second projection  12   c  and can run length-wise along the overhead rail  25  parallel to the length-wise centerline C of the overhead rail  25 . The first running surface  12   e  and the second running surface  12   f  are joined by the radiused junction  12   g . The curve of the radiused junction  12   g  can be a circular section with a radius approximately equal to the outside circumference of the guide roller  39 . This will help create a naturally smooth transition between the first running surface  12   e  and the second running surface  12   f  for the guide roller  39 . The angle between the overhead rails  21 ,  25  is depicted by angle A. The angle between the first running surface  12   e  and the second running surface  12   f  is equal to angle A. In  FIG. 6 , angle A is shown as 90-degrees. However, it is possible that angle A can be greater than 90-degrees (i.e. obtuse) and the inventor envisions that the path guide  12 , can be used where the angle A is 90-degrees or greater. 
     Continuing to refer to  FIG. 6 , the center of the guide roller  39  can be configured to move along the length-wise center line of the overhead rails  21 ,  25 . The outside circumference of the guide roller  39 , therefore moves along a path  42   a  within overhead rail  21  and a path  42   b  within overhead rail  25  that is parallel to the length-wise centerlines C of overhead rail  21  and overhead rail  25  respectively. In this configuration, the path guide  12  is sized and positioned so that the first running surface  12   e  is aligned along path  42   a  and the second running surface  12   f  is aligned along path  42   b . This alignment assures that the first running surface  12   e  and the second running surface  12   f  tangent to the outside circumference of the guide roller  39 . The inventor discovered that by positioning the path guide  12  so that the first running surface  12   e  is aligned along path  42   a  and the second running surface  12   f  is aligned along path  42   b , the resistance of the movable panels  11  of  FIGS. 1-4 , can be significant reduced resulting in the possibility of the user expending less effort to move the movable panels  11  through the transition between overhead rails  21 ,  25 . In addition, the inventor discovered on particularly steep transitions, such as the 90-degree transition between overhead rails  21 ,  25  in  FIG. 6 , extending the second running surface  12   f , and therefore the second projection  12   c  into the overhead rail  25  further helped to reduce resistance and create a smooth transition. 
     The operable carriers  17 ,  19  of  FIG. 5  are typically self-aligning, meaning that operable carriers  17 ,  19  will self-correct their position to stay substantially centered in their respective overhead rails  23 ,  25 ,  27 ,  29 ,  31  of  FIGS. 1-3 . As a result, the guide roller  39  will self-center. Referring again to  FIG. 6 , this means that while the guide roller  39  may wobble slightly as the movable panels  11  are slid, they will self-correct so that the tangent of the outer circumference of the guide roller  39  to move substantially along paths  42   a ,  42   b . The inventor was able to take advantage of the self-centering tendency of the guide roller  39  by convexly radiusing the leading edge  12   d  of the first projection  12   b . If the center of the guide roller  39  is moving on centerline C of overhead rail  21 , the guide roller  39  will directly engage the first running surface  12   e  tangent to the outer circumference of the guide roller  39 . In this scenario, the guide roller  39  has intersected the first running surface  12   e  will a minimal resistance. If the guide roller  39  has wobbled from center the outer circumference of the guide roller  39  will engage the leading edge  12   d  of the first projection  12   b . Because the leading edge  12   d  is convexly radiused, it will push the guide roller  39  back to center causing the outer circumference to guide roller  39  the first running surface  12   e.    
     In order to account for variances in the alignment of the overhead rails  21 ,  25  during assembly, the position of the second running surface  12   f  can be adjusted to align along path  42   b  by loosening the threaded fastener  40  and moving the path guide  12  along slot  12   h . Optionally, after alignment, in order to further affix the path guide  12  to the overhead rail  21 , a hole can be drilled into both the top of the overhead rail  21  and into the main body  12   a , for example, at position  12   i , with the two holes secured by a threaded fastener. 
     While the path guide  12  of  FIG. 6  can typically be used where angle A is 90-degrees or greater, for obtuse angles with less resistance to movement, such as the junction between overhead rails  23  and overhead rail  29  or between overhead rail  23  and overhead rail  31  of  FIGS. 1-3 , the second projection  12   c  of  FIG. 6  may not be necessary.  FIG. 7  illustrates an enlarged view of a portion of  FIG. 1 , at detail  7 , showing the path guide  14  in detail within the junction of overhead rails  23  and overhead rails  29 . The path guide  14  of  FIG. 7  is similarly constructed as the path guide  12  of  FIG. 6  except for the elimination of second projection  12   c  of  FIG. 6 . The path guide  14  includes a main body  14   a , a first projection  14   b , a leading edge  14   d  of the first projection  14   b , a first running surface  14   e , a second running surface  14   f , a radiused junction  14   g  between the first running surface  14   e  and the second running surface  14   f , and a slot  14   h  in the main body  14   a . The path guide  14  can be secured to the overhead rail  23  by a threaded fastener  40  through the overhead rail top  21   e  (as in  FIG. 8 ), as similarly described for  FIG. 6 , and through the slot  14   h . The threaded fastener  40  can be a screw, bolt, combination of a screw or bolt and nut, or any threaded fastener suitable for adjustably and removably securing the path guide  14  to the overhead rail  23 . The main body  14   a  can be substantially rectangular in shade so its position can be constrained to be slidably adjustable only longitudinally, or length-wise, along the overhead rail  23 . As described for  FIG. 6  when referring to  FIG. 8 , the rectangular shape of the main body  14   a  in combination with the slotted surface  21   f  on the inside upper portion of the overhead rail  23  can be constructed to constrain movement of the main body  14   a  to only slide longitudinally along the slotted surface  21   f . A perspective view of the path guide  14  along with the leading edge  14   d , the first running surface  14   e , the second running surface  14   f , the radiused junction  14   g , and the slot  14   h  is illustrated in  FIG. 12 . In addition, the path guide  18 , which is substantially identical to the path guide  14  except for thickness, as illustrated, along with the leading edge  18   d , the first running surface  18   e , the second running surface  18   f , the radiused junction  18   g , and the slot  18   h  is also illustrated in  FIG. 12 . 
     Referring back to  FIG. 7 , the first projection  14   b  projects from the main body  14   a  length-wise along the overhead rail  23  and into the juncture between the overhead rails  23 ,  29 . The first running surface  14   e  is formed along the inside edge of the first projection  14   b  and can run length-wise along the overhead rail  23  parallel to the length-wise center line of the overhead rail  23 . The second running surface  14   f  is formed along a portion of one end of the path guide  14 . The second running surface  14   f  can run parallel to the length-wise centerline C of the overhead rail  29 . The first running surface  14   e  and the second running surface  14   f  are joined by the radiused junction  14   g . The curve of the radiused junction  14   g  can be a circular section with a radius equal to the outside circumference of the guide roller  39 . This will help create a naturally smooth transition between the first running surface  14   e  and the second running surface  14   f  for the guide roller  39 . The angle between the overhead rails  23 ,  29  is depicted by angle B. The angle between the first running surface  14   e  and the second running surface  14   f  is equal to angle B. In  FIG. 7 , angle B is shown as 120-degrees, however, angle B can in general be any obtuse angle. 
     The center of the guide roller  39  can be configured to move along the length-wise center line of the overhead rails  23 ,  29 . The outside circumference of the guide roller  39 , therefore moves along a path  44   a  within overhead rail  23  and a path  44   b  within overhead rail  29  that is parallel to the length-wise centerlines C of overhead rail  23  and overhead rail  29  respectively. In this configuration, the path guide  14  is sized and positioned so that the first running surface  14   e  is aligned along path  44   a  and the second running surface  14   f  is aligned along path  44   b . This alignment assures that the first running surface  14   e  and the second running surface  14   f  tangent to the outside circumference of the guide roller  39 . The inventor discovered that by positioning the path guide  14  so that the first running surface  14   e  is aligned along path  44   a  and the second running surface  14   f  is aligned along path  44   b , the resistance of the movable panels  11  of  FIGS. 1-4 , can be significant reduced resulting in the possibility of the user expending less effort to move the movable panels  11  through the transition between overhead rails  23 ,  29  and likewise, through overhead rails  23 ,  31 . 
     The operable carriers  17 ,  19  of  FIGS. 1-5  are typically self-aligning, as previously described and the guide roller  39  will self-center. Referring again to  FIG. 7 , this means that while the guide roller  39  may wobble slightly as the movable panels  11  are slid, they will self-correct so that the tangent of the outer circumference of the guide roller  39  to move substantially along paths  44   a ,  44   b . As described for  FIG. 6 , for the path guide  14  of  FIG. 7 , the inventor was able to take advantage of the self-centering tendency of the guide roller  39  by convexly radiusing the leading edge  14   d  of the first projection  14   b . If the center of the guide roller  39  is moving on centerline C of overhead rail  23 , the guide roller  39  will directly engage the first running surface  14   e  tangent to the outer circumference of the guide roller  39 . In this scenario, the guide roller  39  has intersected the first running surface  14   e  will a minimal resistance. If the guide roller  39  has wobbled from center the outer circumference of the guide roller  39  will engage the leading edge  14   d  of the first projection  14   b . Because the leading edge  14   d  is convexly radiused, it will push the guide roller  39  back to center causing the outer circumference to guide roller  39  the first running surface  14   e.    
     In order to account for variances in the alignment of the overhead rails  23 ,  29  during assembly, the position of the second running surface  14   f  can be adjusted to align along path  44   b  by loosening the threaded fastener  40  and moving the path guide  14  along slot  14   h . Optionally, after alignment, in order to further affix the path guide  14  to the overhead rail  23 , a hole can be drilled into both the top of the overhead rail  23  and into the main body  14   a , for example, at position  14   i , with the two holes secured by a threaded fastener. 
     The operable carriers  17 ,  19  will now be described in more detail.  FIG. 5  shows both the operable carries  17 ,  19  while  FIG. 8  shows operable carrier  17  in context of the overhead rail  21 . Referring to  FIGS. 5 and 8 , The operable carriers  17 ,  19  include the guide roller  39 , lower helical bearing  41  with a lower bearing lower surface  41   a , upper helical bearing  43 , with an upper bearing lower surface  43   a , a spacer  45  between the upper helical bearing  43  and the lower helical bearing  41 , a threaded fastener  47  that secures the operable carriers  17 ,  19  to the top rail  37   a  of the movable panel  11  via insert  50 . The guide roller  39  can rotate about a spindle  49  on bearings. Alternatively, the guide roller  39  can be fixed to the spindle  49 , and the spindle  49  and guide roller  39  together may rotate around a bearing either on top of or within the upper helical bearing  43 . A bearing  51  below the lower helical bearing  41  can be configured to rotate independently from the lower helical bearing  41 . The upper helical bearing  43 , the lower helical bearing  41 , the bearing  51 , and the guide roller  39  can be horizontally positioned and rotate about a vertical axis. 
     Referring to  FIG. 8 , both the upper bearing lower surface  43   a  and the lower bearing lower surface  41   a  are tapered downward. First projection  21   a , second projection  21   b , third projection  21   c , and fourth projection  21   d  project inward and are tapered downward toward the center of the overhead rail  21 . The first projection  21   a , second projection  21   b , third projection  21   c , fourth projection  21   d , lower bearing lower surface  41   a , and upper bearing lower surface  43   a  are tapered so that the upper helical bearing  43  and the lower helical bearing  41  rest on opposing inside surfaces of the overhead rail  21 . The lower bearing lower surface  41   a  rest on the third projection  21   c  while the upper bearing lower surface  43   a  rests on the first projection  21   a . The upper helical bearing  43  and the lower helical bearing  41  are disposed to rotate in opposite directions. This arrangement causes the operable carriers  17  to self-center. As the operable carrier  17  shifts to one side or the other, the downward taper of the first projection  21   a , the second projection  21   b , the third projection  21   c , and the fourth projection  21   d  in combination with the inward taper of the upper bearing lower surface  43   a  and the lower bearing lower surface  41   a  will cause the operable carrier  17  to re-center itself. In addition, bearing  51  is tightly coupled to the inside surface of the throat  21   g  of the overhead rail  21 , and this limits the extent of the movement of the upper helical bearing  43  and the lower helical bearing  41  from side to side. 
     While the operable carriers  17 ,  19  are illustrated using a pair of helical bearings as shown in  FIGS. 5 and 8 , the movable partition system  10  is not limited to such an arrangement. Other self-centering overhead carriers that utilize a horizontal guide roller rotatable about a vertical axis can be utilized. For example, the carriers illustrated in U.S. Pat. No. 3,879,799 “Multidirectional Suspension System for Operable Partitions,” (Williams) and U.S. Pat. No. 5,230,123, “Operable Wall Deployment and Storage System” (Williams). In addition, systems with self-aligning horizontal roller that engage inside projected surfaces of the overhead rails can be used. 
       FIGS. 9 and 10  illustrate the movable partition system  10  with path guides  12 ,  16  in relationship with overhead rails  21 ,  23 ,  25 ,  27  in two different perspective cutaway views.  FIG. 9  illustrates a portion of  FIG. 1  in top and front perspective and in partial-cutaway view.  FIG. 10  illustrates a portion of  FIG. 1  in top and front perspective and in top-cutaway view. Referring to  FIGS. 9 and 10 , path guides  12 ,  16  can both positioned against the slotted surface  21   f  ( FIG. 9 ). However, path guide  16  is thicker than path guide  12  allowing the guide roller  39  of the operable carrier  19  to pass under path guide  12  but to engage path guide  16 .  FIG. 9  shows the relationship between the upper helical bearing  43  and the second projection  21   b  of overhead rail  21  as well as the relationship between the lower helical bearing  41  and the third projection  21   c .  FIG. 10  illustrates the relationship between the operable carriers  17 ,  19  and the first projections  21   a ,  23   a ,  25   a ,  27   a  of overhead rails  21 ,  23 ,  25 ,  27  respectively.  FIG. 10  also illustrates the relationship between the operable carriers  17 ,  19  and the second projections  21   b ,  23   b ,  25   b ,  27   b  of overhead rails  21 ,  23 ,  25 ,  27  respectively. Both  FIGS. 9 and 10  illustrate a top portion of the movable panel  11  in relationship to the overhead rails  21 ,  23 ,  25 ,  27 . The top portion of the movable panel  11  is shown with the infill panel  35  surrounded by the top rail  37   a , and vertical stiles  37   b ,  37   c . In  FIG. 9  the threaded fasteners  47  of the operable carriers  17 ,  19  are shown secured in a groove  37   e  in the top rail  37   a  via the insert  50 . 
       FIGS. 11 and 12  illustrate the movable partition system  10  with path guides  14 ,  18  in relationship with overhead rails  21 ,  23 ,  25 ,  27  in two different perspective cutaway views.  FIG. 11  illustrates a portion of  FIG. 1  in top and front perspective and in partial-cutaway view.  FIG. 12  illustrates a portion of  FIG. 1  in top and front perspective and in top-cutaway view. Referring to  FIGS. 11 and 12 , path guides  14 ,  18  can both positioned against the slotted surface  23   f  ( FIG. 11 ). However, path guide  18  is thicker than path guide  14  allowing the guide roller  39  of the operable carrier  19  to pass under path guide  14  but to engage path guide  18 .  FIG. 11  shows the relationship between the upper helical bearing  43  and the second projection  23   b  of overhead rail  21  as well as the relationship between the lower helical bearing  41  and the third projection  23   c .  FIG. 12  illustrates the relationship between the operable carriers  17 ,  19  and the first projections  23   a ,  29   a ,  31   a  of overhead rails  23 ,  29 ,  31  respectively.  FIG. 12  also illustrates the relationship between the operable carriers  17 ,  19  and the second projections  23   b ,  29   b ,  31   b  of overhead rails  23 ,  29 ,  31  respectively. Both  FIGS. 11 and 12  illustrate a top portion of the movable panel  11  in relationship to the overhead rails  23 ,  29 ,  31 . The top portion of the movable panel  11  is shown with the infill panel  35  surrounded by the top rail  37   a , and vertical stiles  37   b ,  37   c . In  FIG. 11  the threaded fasteners  47  of the operable carriers  17 ,  19  are shown secured in a groove  37   e  in the top rail  37   a  via the insert  50 . 
       FIGS. 1-4 and 9-12  illustrate an arrangement of overhead rails  21 ,  23 ,  25 ,  27 ,  29 ,  31 , and path guides  12 ,  14 ,  16 ,  18 , in combination with movable panels  11  can each sliding along the overhead rails  21 ,  23 ,  25 ,  27 ,  29 ,  31 . FIGS.  13 - 20  illustrate portions of a movable partition system  10 . As illustrated in  FIGS. 13, 14, 17, 19-21 , the movable panels  57 ,  58 ,  59  slide are configured as a slidable folding panel assembly  56  with only one of the movable panels  58  engaging the overhead rails  52 ,  53 ,  54 ,  55  and path guide  12  via operable carriers  17 ,  19  and guide rollers  39 . A complete system may include one or more slidable folding panel assembly  56 , or one or more slidable folding panel assemblies  56  in combination with one or more fixed or sliding panels. For simplicity, one of a slidable folding panel assembly  56  is illustrated. The movable panels  57 ,  58 ,  59  slide as a unit by virtue of hinges and hinges  61  hinging the movable panel  57  and movable panel  59  in opposite directions about movable panel  58 . Hinge  60  hinges the movable panel  59  about the movable panel  58 . Hinge  61  hinges the movable panel  57  about movable panel  58 . The combination of overhead rails  52 ,  53 ,  54 ,  55  illustrated is but one example of an alternative to the rail combination of  FIG. 1 . Many other arrangements and combinations of overhead rails can easily be used for the movable partition system  10  of this disclosure. 
       FIGS. 13, 14, 17, and 19-21  show a typical sequence for opening the slidable folding panel assembly  56  from an extended or closed position to an open position or end position. Referring to  FIG. 13 , the slidable folding panel assembly  56  is in a closed or extended position with movable panels  57 , 58 ,  59  extended horizontally along overhead rail  52 . The movable panels  57 ,  58 ,  59  are illustrated in dashed (i.e. broken) lines to indicate that they are hidden below the rail. The doors can be optionally locked by a lock  62  as shown in  FIG. 15 . The lock can any lock suitable for the particular application or desired level of security. For example, a mortise deadbolt lockset or a three-point lockset, among others, could be used for secure a storefront. 
     Referring to  FIGS. 14 and 15 , movable panel  57  and movable panel  59 , fold on opposite sides of the movable panel  58  because they are hinged on opposite sides of movable panel  58 , i.e. hinge  60  and hinge  61  are on opposite sides of the movable panel  58 .  FIG. 15  illustrates additional detail such as an infill panel  35  and vertical stiles  37   b ,  37   c . The top rail  37   a , which is shown in  FIG. 16 , is removed in  FIG. 15  for clarity. The infill panel  35  is illustrated as a glass or glazed infill such as an IGU. As previously discussed for  FIGS. 1-12 , the movable panels  11  can be any movable panel  11  that meet the architectural or building requirements, such as wood, metal, or glazed panels. Referring to  FIGS. 14 and 17 , folding the movable panels  57 ,  59  about opposite faces of movable panel  58 , allows the panels to slide together as with only movable panel  58  engaged with overhead rails  52 ,  53 ,  54 ,  55  via operable carriers  17 ,  19 . The operable carriers  17 ,  19  are shown in dashed or broken lines to indicate that they are hidden or partially hidden within the overhead rail  52 . 
     Referring to  FIG. 19 , the right side, or leading side, of the slidable folding panel assembly  56  is slid to the juncture of overhead rail  53  and overhead rail  54  where the guide roller  39  of operable carrier  17  encounters the path guide  12  and is diverted along the path guide  12 . Referring to  FIG. 18 , the path guide  12  shown with the first projection  12   b  projecting from the main body  12   a  length-wise along the overhead rail  53  and into the juncture between the overhead rail  53  and overhead rail  54 . The first running surface  12   e  is formed along the inside edge of the first projection  12   b  and can run longitudinally along the overhead rail  53  parallel to the length-wise center line C of the overhead rail  53 . The second projection  12   c  can projects from the main body  12   a  longitudinally (i.e. length-wise) into the overhead rail  54  from the juncture between the overhead rails  53  and overhead rail  54 . The second running surface  12   f  is formed along the inside edge of the second projection  12   c  and can run length-wise along the overhead rail  54  parallel to the length-wise centerline C of the overhead rail  54 . The first running surface  12   e  and the second running surface  12   f  are joined by the radiused junction  12   g . The curve of the radiused junction  12   g  can be a circular section with a radius approximately equal to the outside circumference of the guide roller  39 . This will help create a naturally smooth transition between the first running surface  12   e  and the second running surface  12   f  for the guide roller  39 . The angle between the overhead rails  53 ,  54  is depicted by angle A. The angle between the first running surface  12   e  and the second running surface  12   f  is equal to angle A. In  FIG. 6 , angle A is shown as 90-degrees. However, it is possible that angle A can be greater than 90-degrees (i.e. obtuse) and the inventor envisions that the path guide  12 , can be used where the angle A is 90-degrees or greater. 
     Continuing to refer to  FIG. 18 , the center of the guide roller  39  can be configured to move along the length-wise center lines C of the overhead rails  53 ,  54  respectively. The outside circumference of the guide roller  39 , therefore moves along a path  42   a  within overhead rail  53  and a path  42   b  within overhead rail  54  that is parallel to the length-wise centerlines C of overhead rail  53  and overhead rail  54  respectively. In this configuration, the path guide  12  is sized and positioned so that the first running surface  12   e  is aligned along path  42   a  and the second running surface  12   f  is aligned along path  42   b . This alignment assures that the first running surface  12   e  and the second running surface  12   f  tangent to the outside circumference of the guide roller  39 . 
     As previously discussed for the movable partition system  10  of  FIG. 1 , the operable carriers  17 ,  19  of  FIG. 16  are typically self-aligning, meaning that operable carriers  17 ,  19  will self-correct their position to stay substantially centered in their respective overhead rails  52 ,  53 ,  54 ,  55  of  FIGS. 13, 14, 17, and 19-21 . As a result, the guide roller  39  will self-center. Referring again to  FIG. 18 , this means that while the guide roller  39  may wobble slightly as the movable panels  11  are slid, they will self-correct so that the tangent of the outer circumference of the guide roller  39  to move substantially along paths  42   a ,  42   b . As previously discussed, the inventor was able to take advantage of the self-centering tendency of the guide roller  39  by convexly radiusing the leading edge  12   d  of the first projection  12   b . If the center of the guide roller  39  is moving on centerline C of overhead rail  53 , the guide roller  39  will directly engage the first running surface  12   e  tangent to the outer circumference of the guide roller  39 . In this scenario, the guide roller  39  has intersected the first running surface  12   e  will a minimal resistance. If the guide roller  39  has wobbled from center the outer circumference of the guide roller  39  will engage the leading edge  12   d  of the first projection  12   b . Because the leading edge  12   d  is convexly radiused, it will push the guide roller  39  back to center causing the outer circumference to guide roller  39  the first running surface  12   e.    
     In order to account for variances in the alignment of the overhead rails  53 ,  54  during assembly, the position of the second running surface  12   f  can be adjusted to align along path  42   b  by loosening the threaded fastener  40  and moving the path guide  12  along slot  12   h . Optionally, after alignment, in order to further affix the path guide  12  to the overhead rail  21 , a hole can be drilled into both the top of the overhead rail  21  and into the main body  12   a , for example, at position  12   i , with the two holes secured by a threaded fastener. 
     Referring to  FIG. 20  the operable carrier  17  guides the right side of the slidable folding panel assembly  56  along overhead rail  54  toward overhead rail  55 . Operable carrier  19  guides the left side of the slidable folding panel assembly  56  along overhead rail  53  toward path guide  12 . In  FIG. 21 , operable carrier  17  has guided the right-hand side of the slidable folding panel assembly  56  to an open position along overhead rail  55 . Operable carrier  19  guided the left-hand side of the slidable folding panel assembly  56  past path guide  12  to an open position along overhead rail  53 . Referring to  FIG. 16 , the guide roller  39  of the operable carrier  17  extends upward a distance to engage the path guide  12  while the guide roller  39  of the operable carrier  19  extends upward a lesser distance so as not to engage (i.e. bypass) path guide  12 . 
     In order to better understand how this works,  FIG. 16  illustrates an enlarged view of a top portion of the slidable folding panel assembly  56  of  FIG. 13  showing the operable carriers  17 ,  19  attached to the top rail  37   a  of the sash  37  of the movable panel  58 . The movable panels  57 ,  59  do not need the operable carriers  17 ,  19  since only movable panel  58  slides along overhead rails  52 ,  53 ,  54 ,  55  of  FIG. 13 . As previously described, the movable panels  57 ,  59  are hinged to movable panel  58 .  FIG. 16  shows a portion of the hinge  60  mounted to an upper portion of the vertical stile  37   c  of movable panel  58  and an upper portion of the vertical stile  37   b  of movable panel  59 . While only a portion of one of the hinge  60  is shown, the movable panels  58 ,  59  can be hinged together by two, three or more hinges  60 . Similarly, a portion of the hinge  61  is mounted to an upper portion of the vertical stile  37   c  of movable panel  57  and an upper portion of the vertical stile  37   b  of movable panel  58 . The hinge  61  is shown in dashed, or broken lines, to indicate it is hidden from view and mounted on the opposite face of the slidable folding panel assembly  56 . Again, while only a portion of one of the hinge  61  is shown, the movable panels  57 ,  58  can be hinged together by two, three or more hinges  61 . 
     As previously discussed for  FIG. 5 , operable carriers  17 ,  19  are virtually identical except for the height of the guide roller  39  relative to top rail  37   a  thanks to the height of spindle  49 . The height of the guide roller  39  of operable carrier  17  is set to engage path guide  12 , while the height of guide roller  39  of operable carrier  19  is set as to not engage path guide  12 . The other components of the operable carriers  17 ,  19  including the upper helical bearing  43 , upper bearing lower surface  43   a , lower helical bearing  41 , lower bearing lower surface  41   a , spacer  45 , bearing  51 , and other components are in the same functional and structural relationship as described for  FIG. 5 . Similarly the operable carriers  17 ,  19  can be secured to the to the top rail  37   a  by a threaded fastener  47  extending from each operable carrier  17 ,  19  and into a corresponding insert  50  in the top rail  37   a  as previously described for  FIG. 5 . Alternatively, the operable carriers  17 ,  19  can be secured to the movable panel  58  by other threaded or non-threaded fasteners, inserts in combination with threaded fasteners, or other fastening combinations capable of support the weight of all three of the movable panels  57 ,  58 ,  59  in the overhead rails  52 ,  53 ,  54 ,  55  of  FIG. 13 . As previously discussed, the operable carriers  17 ,  19  are not limited to the operable carriers  17 ,  19  illustrated. Other self-centering overhead carriers that utilize a horizontal guide roller rotatable about a vertical axis can be utilized. For example, the carriers illustrated in U.S. Pat. No. 3,879,799 “Multidirectional Suspension System for Operable Partitions,” (Williams) and U.S. Pat. No. 5,230,123, “Operable Wall Deployment and Storage System” (Williams). In addition, systems with self-aligning horizontal roller that engage inside projected surfaces of the overhead rails can be used. 
     In order to help facilitate movement of the slidable folding panel assembly  56 , the door panels can optionally be latched together using a door catch  70  as shown in  FIG. 17  and in more detail in  FIG. 22 . The door catch  70  illustrated in  FIG. 22  is from the inventor&#39;s U.S. Pat. No. 9,228,387 “Door Catch,” issued Jan. 5, 2016. This door catch  70  is shown as an example. Any suitable door catches or door-to-door latching mechanisms could be used that have sufficient strength to hold the doors together while they are being slid or slid and pivoted along overhead rails, such as the overhead rails  52 ,  53 ,  54 ,  55  of  FIG. 13 .  FIG. 22  shows a side view of movable panels  57 ,  58 ,  59  shown in side view along view lines  22 - 22  of  FIG. 17 . For clarity, the door catch  70  between movable panel  57  and movable panel  58  is illustrated in section view. Referring to  FIG. 22 , the door catch  70  includes a catch bar bracket  71  and a catch bar base  72 . The catch bar bracket  71  is also shown in  FIGS. 15 and 17 . The catch bar base  72  is also shown in  FIG. 15 . Referring back to  FIG. 22 , the catch bar bracket  71  and the catch bar base  72  are held in tension by ball catch  73  and a detent at the bottom of the catch bar bracket  71 . The tension of the ball catch  73  is adjustable by threadably moving the ball catch  73  up or down within the catch bar base  72 . A tool-receiving end  76  receives a wrench, screw driver, hex-key or other tool to facilitate turning of the ball catch  73 . The door catches  70  are fastened to the movable panels  57 ,  58 ,  59  by threaded fasteners  74  through apertures  75 . 
     As previously discussed, one of the advantages of the movable partition system  10  of the present disclosure is that a bottom rail system is optional. In some conditions, for example, when the movable partitions are heavy glazed door panels or heavy sliding folding panel assemblies, it may be desirable to add a bottom rail.  FIG. 23  illustrates, in top plan view, an optional bottom rail system  80  using a path guide of the present disclosure, such as the path guide  14 . The movable panel  11 , shown in  FIG. 24 , is removed for clarity.  FIG. 24  illustrates, in perspective view, the optional bottom rail system  80  using a path guide  14  of the  FIG. 23 . Referring to  FIGS. 23 and 24 , the path guide  14  is shown as described for  FIG. 7  including the main body  14   a , the first projection  14   b , the leading edge  14   d , the first running surface  14   e , and the second running surface  14   f , and radiused junction  14   g . The guide roller  39  interacts and aligns with the path guide  14  in the same way as previously described. As described for  FIG. 7 , the guide roller  39  moves optionally along the leading edge  14   d  and then along the first running surface  14   e  and the second running surface  14   f . The first running surface  14   e  and the second running surface  14   f  are positioned along the tangent of the outer circumference of the guide roller  39 . The guide roller  39  is centered along the length-wise axis of the bottom rails  77 ,  78 . The path guide  14  is aligned at the junction between a bottom rail  77  and a bottom rail  78 . The position of the path guide  14  is adjustable via a threaded fastener  40  and the slot  14   h  as described for  FIG. 7 . The door panel ( FIG. 24 ) is moves along the bottom rails  77 ,  78  via a horizontal roller  79 . While a horizontal roller  79  is illustrated, the optional bottom rail system  80  is not limited to a horizontal roller  79 , a helical bearing, such as those previously described could easily be substituted. In addition, while path guide  14  is shown, path guide  12  could readily be substituted and still within the scope of the optional bottom rail system  80 . 
     A movable partition system  10  that includes path guides  12 ,  14 ,  16 ,  18  has been described. It is not the intent of this disclosure to limit the claimed invention to the examples, variations, and exemplary embodiments described in the specification. Those skilled in the art will recognize that variations will occur when embodying the claimed invention in specific implementations and environments. For example, while a specific combination of overhead rails  21 ,  23 ,  25 ,  27 ,  29 ,  31  has been illustrated, such as the combination of  FIGS. 1-4  and  FIGS. 9-12 , and an alternative combination illustrated in  FIGS. 13-20 , other rail combinations are possible. In another example, additional overhead rails could be added in parallel or series in various combinations of right-angle and obtuse junction between rails, or all right-angle junctions between rails, or all obtuse junctions between rails, that would still be within the spirit of the movable partition system  10  disclosed. In a further example, as previously discussed, the path guide  12  of  FIGS. 6, 9, and 10 , and its thicker counterpart the path guide  16  of  FIGS. 9 and 10 , while illustrated with a 90-degree angle between the first running surface  12   e ,  16   e  and the second running surface  12   f ,  16   f , could be adapted for use with obtuse angles and still be within the spirit of the movable partition system  10 . Path guides are shown in various combinations throughout this disclosure. The claimed invention is not limited to these particular combination of path guides. The inventor envisions that the path guides can be implemented in a variety of combinations. For example, while path guide  12  of  FIGS. 6, 9, and 10  is shown with its thicker counterpart, the path guide  16  of  FIGS. 9 and 10 , path guide  12  or path guide  16  can be implemented individually without the other. Similarly, in  FIG. 1 , path guide  14  and  18  are illustrated in combination, these also can be implemented individually without the other. 
     While the slidable folding panel assembly  56  of  FIGS. 13-17 and 19-21  is illustrated with the path guide  12 , and overhead rails  52 ,  53 ,  54 ,  55 , the inventor envisions that the slidable folding panel assembly  56  can be implemented in a variety of environments, with a variety of overhead rail combinations, with or without path guides or with path guides other than the path guides  12 ,  14 ,  16 ,  18  illustrated in this disclosure. 
     It is possible to implement certain features described in separate embodiments in combination within a single embodiment. Similarly, it is possible to implement certain features described in single embodiments either separately or in combination in multiple embodiments. The inventor envisions that these variations fall within the scope of the claimed invention. For example, the slidable folding panel assembly  56  of  FIGS. 13-17 and 19-21  can be implemented in a track assembly similar to  FIGS. 1-3  with by reversing the operable carriers  17 ,  19  shown in  FIG. 18  so they are configured similarly to  FIG. 5 . Similarly, the movable panels  11  can be implemented in the overhead rail combination of  FIGS. 13, 14, 17, and 19-21  by reversing the order of the operable carriers  17 ,  19  in  FIG. 5  as illustrated in  FIG. 18 . As another example, the optional bottom rail system  80  of  FIGS. 23 and 24  could be implemented in any of the other examples given throughout this disclosure. 
     While the examples, exemplary embodiments, and variations are helpful to those skilled in the art in understanding the claimed invention, it should be understood that, the scope of the claimed invention is defined solely by the following claims and their equivalents.