Abstract:
The present invention is directed to an apparatus for erecting a retractable wall system. More particularly, this invention relates to a retractable wall system and its components which may be used to divide a room or space, create an acoustic barrier, create a freestanding structure, or provide an awning.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to apparatus for erecting a retractable wall system. More particularly, this invention relates to a retractable wall system and its components which may be used to divide a room or space, create an acoustic barrier, create a freestanding structure, or provide an awning. 
     BACKGROUND 
     Roller shades may be useful for blocking out light and enhancing privacy for windows. Retractable walls may provide the ability to divide a room or provide shade for exterior porches. Still, a need exits for improved retractable wall systems that may span longer distances and utilize heavier fabrics. 
     SUMMARY 
     Hence, the present invention is directed to a track for a retractable wall system which includes an elongated member having a first cross-sectional profile. The first cross-sectional profile may include a front wall, a rear wall spaced from the front wall, and a bottom wall connecting the front wall and the back wall. The first cross-sectional profile may include a first top wall adjacent the front wall, a second top wall adjacent the rear wall, and an open channel disposed between the first top wall and the second top wall. The open channel may include a first side wall connected to the first top wall, a second side wall connected to the second top wall, a first ledge extending from the first side wall into the open channel, and a second ledge extending from the second side wall into the open channel. The first and second ledges may define a slot between the first side wall and the second side wall. The first cross-sectional profile further may include a conduit disposed between the front wall and the rear wall which is connected to the open channel via the slot. 
     In another aspect of the invention, the first cross-sectional profile further may include a lateral wall that extends from the front wall to the back wall. The conduit may be formed by the first ledge, the second ledge, the first side wall, the second side wall, and the lateral wall. The lateral wall may be connected to the first side wall and the second side wall. 
     In another aspect of the invention, the first cross-sectional profile may include an interior wall that extends from the front wall to the back wall. The front wall, lateral wall, rear wall and interior wall may define a first interior channel. The front wall, interior wall, rear wall and bottom wall may define a second interior channel. The front wall, the first top wall, the first side wall and the lateral wall may define a third interior channel. And, the rear wall, the second top wall, the second side wall and the lateral wall may define a fourth interior channel. 
     In another aspect of the invention relates to a retractable wall system which may include a tube having with a longitudinal axis, a first track disposed perpendicular to the longitudinal axis, a second track spaced from the first track, and a third track. The third track may include a first traveling guide disposed in the open channel of the first track and a second traveling guide disposed in the open channel of the second track. The retractable wall system further may include a flexible membrane barrier sheet connected to the tube. The sheet may include first, second and third zippered sides. The first zippered side may be disposed in the conduit of the first track and secured to the first traveling guide. The second zippered side may be disposed in the conduit of the second track and secured to the second traveling guide. The third zippered side may be disposed in the conduit of the third track. 
     In another aspect of the invention, the tube may be a thin wall hollow member. The tube may have a cross-sectional profile that comprises a substantially circular outer wall. The cross-sectional profile further may include a plurality of interior structural members. The plurality of interior structural members may each define a chord within the tube. 
     In another aspect of the invention, each interior structural member may connect to an adjacent structural member to form an external node which is located about the circumference of the tube. Each interior structural member further may connect to a second adjacent structural member to form another external node that is located about the circumference of the tube. The intersection of two structural members at an external node may form a right angle. 
     In another aspect of the invention, each interior structural member may intersect another interior structural member to form an internal node. The intersection of two interior structural members at an internal node may form an obtuse angle, which may measure approximately 135 degrees. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate an embodiment of the invention, and together with the general description given above and the detailed description given below, serve to explain the features of the invention. 
         FIG. 1  is a perspective view of a covered patio enclosed on two sides by an embodiment of the retractable wall system of the present invention; 
         FIG. 2  is an exploded view of an exemplary embodiment of the retractable wall system of the present invention; 
         FIG. 3  is a partial sectional view of the first retractable wall system along line  3 - 3  of  FIG. 1 ; 
         FIG. 4  is a sectional view of the tube of  FIG. 3 ; 
         FIG. 5  is a sectional view of another embodiment of the tube of  FIG. 3 ; 
         FIG. 6  is a perspective view of an exploded view of an idler and tube of  FIG. 3 ; 
         FIG. 7  is a perspective view of the idler and tube of  FIG. 6  being assembled; 
         FIG. 8  is a partial sectional view of the tube, horizontal track, and flexible barrier of  FIG. 1 ; 
         FIG. 8 a    is a partial sectional view of  FIG. 8 ; 
         FIG. 9  is a partial cross-sectional view of the left side track and horizontal track of  FIG. 1 , taken perpendicular to the longitudinal axis of the left side track; 
         FIG. 10  is a cross-sectional view of the horizontal track of  FIG. 1 , taken perpendicular to its longitudinal axis; 
         FIG. 11  is a cross-sectional view of another embodiment of the horizontal track of  FIG. 1 , taken perpendicular to its longitudinal axis; 
         FIG. 12  is a partial sectional view of the head rail of  FIG. 1 , taken perpendicular to the vertical tracks and from below the tube and motor assembly; 
         FIG. 13  is a partial sectional view of the head rail, tube and motor assembly of  FIG. 1 , taken parallel to the vertical tracks; 
         FIG. 14  is an exploded view of the right side end-cap assembly of the retractable wall system of  FIG. 1 ; 
         FIG. 15  is a cross-sectional view of the right side track along with a partial cross-sectional view of the horizontal track of  FIG. 1 . 
         FIG. 16  is a perspective view of a pair of adjacent tracks and end caps from abutting retractable wall systems of  FIG. 1 . 
         FIG. 17  is a detailed view of a pair of tracks aligned to form a corner assembly; 
         FIG. 17 a    is a view of the tracks of  FIG. 17  fastened together to form a corner assembly; 
         FIG. 18  is a perspective view of a free standing retracting wall system structure; 
         FIG. 19  is a plan view of the free standing structure of  FIG. 18 ; 
         FIG. 20  is a perspective view of an exemplary retractable awning system; 
         FIG. 21  is a sectional view of the left track of the retractable awning system of  FIG. 20 ; 
         FIG. 22  is a side view of the retractable awning system of  FIG. 20 ; 
         FIG. 23  is a sectional view of the front partition of the retractable awning system of  FIG. 20 ; 
     
    
    
     DESCRIPTION 
       FIG. 1  is a perspective view of a patio enclosure  10  formed by three retractable wall systems  12 ,  14 ,  16 . The first retractable wall system  12  may be disposed perpendicular to the house and may extend from the side of the house to a first corner of the patio. The second retractable wall system  14  may be disposed perpendicular to the first retractable wall system  12  and may be parallel to the sliding door of the house. The third retractable wall system  16  may be next to the second retractable wall system  14 . The first retractable wall system  12  may be disposed in an opening under the roof structure of the house. The first retractable wall system  12  may include a head rail  18 , a left side track  20 , right side track  22 , and a horizontal track  24  disposed between the left side track  20  and the right side track  22 . In a preferred embodiment, the left side track  20 , the right side track  22  and the horizontal track  24  have the same cross-sectional profile. 
     In  FIG. 1 , the first retractable wall system  12  is in a raised configuration. In the raised configuration the horizontal track  24  abuts the head rail  18 . Referring to  FIG. 3 , the head rail  18  may contain a roll of flexible barrier material  26   a , as well as a mechanism (not shown)  28  for raising and lowering the flexible barrier membrane  26 . As shown in  FIG. 2 , the mechanism  28  may include an electrical motor  42 , which may be controlled by a wireless remote or switch. Alternatively, the mechanism may include a hand crank or a chain drive with a looped strap for manually raising and lowering the flexible barrier membrane. 
     Referring to  FIG. 1 , the left side track  20  of the first retractable wall system  12  may be secured to the building. By contrast, the right side track  22  of the first retractable wall system  12  may be connected to the left side track  32  of the second retractable wall system  14  at a 90 degree angle to form a corner assembly. The second retractable wall system  12  is shown in a partially lowered configuration. A flexible barrier material  34  may be disposed between the left side track  32 , right side track  36  and horizontal track  38  of the second retractable wall system  14 . The flexible barrier material  34  may extend from inside each of these three tracks  32 ,  36 ,  38  to create a wall. 
     As shown in  FIG. 3 , the flexible barrier material  26  may be disposed on a tube  40  in the head rail. The flexible barrier material  26  may be rolled onto the tube  40  and unwound from the tube as the horizontal track  24  is lowered. Referring to  FIG. 1 , the third retractable wall system  16  may be disposed parallel to the second retractable wall system  14 . The right side track of the second retractable wall system  14  and the left side track of the third retractable wall system  16  may be secured together or connected to a secondary structural member (e.g., a post or stud). The third retractable wall system  16  is shown in the lowered configuration. 
       FIG. 2  shows an exploded view of the first retractable wall system  12 . The retractable wall system  12  may include a left side track  20 , a right side track  22 , and a horizontal track (or weight bar)  24  extending between the left side track and the right side track. Additionally, the retractable wall system  12  may include a left side end-cap  46  which is secured into the left side track  20  and a left side feeder-clip  48  that is positioned in the left side end-cap  46 . Similarly, the retractable wall system  12  includes a right side end-cap which may be secured into the right side track  22 , as well as a right side feeder-clip  52  that may be disposed in the right side end-cap  50 . When the left side end-cap  46  is fully seated in the left side track  20  the left side feeder-clip  48  interlocks with features of the left side track  20  cross sectional profile to further secure the left end-cap to the left side track. Similarly, when the right side end-cap  50  is fully seated in the right side track  22 , the right side feeder-clip  52  interlocks with features of the right side track  22  cross-sectional profile to further secure the right end-cap to the right side track. Each end-cap  46 ,  50  further may include a cylindrical stub  54  in the end-cap wall. The cylindrical stub  54  may receive the tube assembly and serve as axis of rotation for the tube  40 . 
     The roller tube assembly may include an idler  56 , a tube  40  having a central axis, and a mechanism  28  for rotating the tube  40  about the central axis of the tube. In a preferred embodiment, the mechanism  28  may include a motor  42  that is partially installed with the tube  40 . The motor  42  may include a built in radio control receiver that provides a user the capability to operate the motor with a remote control. For example, the motor may be a Somfy RTS motor. 
     In  FIG. 2 , the mechanism  28  for rotating the tube includes a motor  42  with a remote control. The motor, which may be slidably received within the tube  40 , may include a drive  58  and a crown  60 . The drive  58  and crown  60  may be external features of the motor which interlock with an interior surface  62  of the tube so as to provide a mechanism for transferring rotational movement from the motor or the tube. The motor  42  further may include a drive wheel  64  at one end. The drive wheel  64  may be configured and dimensioned to be fixedly received within a motor bracket  66 . The motor bracket  66  may be secured to one end-cap  50 . The tube assembly  28  further may include a sheet of flexible material  26 . The sheet of flexible material  26  may include a zipper border  68  on at least three sides. The sheet of flexible material  26  may be cut to be received in a pair of traveling guide pieces  70 ,  72  that are adapted to be received in the horizontal track  24 . 
       FIG. 3  shows a cross-section of the retractable wall system  12  taken perpendicular to the central axis  74  of the tube  40 . The tube  40  may be mounted on the cylindrical stub  54  of the left end-cap  46 . The tube  40  may be secured to the idler  54  with a fastener. Inside the tube  40  are interior wall segments  78 , which form a mating structure for the motor drive and crown. The interior wall segments  78  may be arranged to provide structural rigidity to the tube. In particular, the interior wall segments may span the internal space of the tube  40  so as to provide a three dimensional truss or space frame. Additionally, the tube may include a fabric pocket receiving channel  80  and a fabric zipper receiving channel  82 , which may be used to connect the flexible barrier material  26  to the tube  40 . Wrapped around the tube  40  is a sheet of flexible barrier material  26   a , which may include a heat bonded zipper edge  68  on the left side and the bottom side of the sheet. 
     The end-cap  46  may be situated within the left side track  20 . The left side of the flexible barrier material sheet  26  may be fed through the left side feeder-clip  48  into a rigid receiving channel  84   a  in the left side track  20 . The bottom side of the flexible barrier material  26  sheet may be received within the horizontal track  24 . The cross-sectional profile of the left side track  20  and horizontal track  24  may be the same. Accordingly, the flexible barrier material  26  may be secured to the horizontal track  24  through a rigid receiving channel  86  in the horizontal track  24 . A slot  88  may connect the rigid receiving channel  88  to an internal anchoring cavity  90  that is configured and dimensioned to receive the bonded zipper edge  68  of the sheet. The rigid receiving channel  86  may be disposed between a pair of arcuate walls  92 . The internal anchoring cavity  90  may be disposed adjacent to the rigid receiving channel  86 . 
     The horizontal track  24  further may include a primary accessory receiving channel  94 , a secondary accessory receiving channel  96 , and a tertiary accessory receiving channel  98 . Weights, for example, steel bars  100  may be placed with the primary accessory receiving channel  94  or the secondary accessory receiving channel  96  of the horizontal track  24  to facilitate lowering of the flexible material barrier  26 . In another example, sound dampening material may be inserted in these spaces to increase the sound insulating properties of the retractable wall system. An elastomeric end cap, flexible seal, or brush may be inserted in the tertiary accessory receiving channel  98  to provide an improved connection with the ground surface for purposes such as, without limitation, increasing wall stability, slip resistance, draft prevention, or sound dampening. 
       FIG. 4  shows a cross section of a preferred embodiment of the tube  40 . Generally, the tube  40  may be a thin-wall hollow member. The outer surface  102  of the tube may be substantially circular, and the interior space of the tube may include a series of interior wall segments (or structural members)  78 , which may reinforce the tube against bending moments that may be generated from the weight of flexible barrier material on the tube when the tube is positioned between the end caps. Each structural member  78  may form a cord within the tube  40 . Each structural member  78  may connect to an adjacent structural member  78  to form an external node  104 , which is located about the circumference of the tube. Additionally, each structural member  78  may intersect two other structural members  78  to form a pair of internal nodes  106 . The intersection of a pair of structural members  78  at an external node  104  forms a right angle. The intersection of a pair of structural members  78  at an internal node forms an obtuse angle of approximately 135 degrees. The space between an internal node  106  and outer wall  108  of the tube may be used to house the pocket receiving channel  80  and the zipper receiving channel  82 . Additionally, a fastener alignment groove  110  may be disposed above one or more internal nodes on the outer surface  102  of the tube. The interior surface  62  of the tube may form an eight sided shape for receiving a motor (with a mating drive and crown) or an octangonal tube for non-motorized applications (e.g., 40 mm, 60 mm, or 80 mm tubes). 
       FIG. 5  shows the cross-section of another embodiment of the tube  40 ′. In this embodiment, the outer surface  112  of the tube  40 ′ is substantially circular and the interior space includes a series of structural members  114  that reinforce the tube  40 ′ from bending moments as in the previous embodiment. In contrast to the tube of  FIG. 4 , however, each structural member  114  connects to the outer wall  116  of the tube at one location (or external node)  118 . Additionally, the opposite end of each structural member  114  may connect to an adjacent structural member  114  to form an internal node  120 . The interior surface  122  of the tube  40 ′ may form an eight sided shape for receiving a motor (with a mating drive and crown) or an octangonal tube for non-motorized applications (e.g., 40 mm, 60 mm, or 80 mm tubes). In this embodiment, the tube  40 ′ also may include a pocket receiving channel  124 , a zipper receiving channel  126 , and two fastener alignment grooves  128 . 
     Referring to  FIGS. 4 and 5 , the tube  40 ,  40 ′ may have an outer diameter of approximately 1.0 inches to approximately 6.0 inches, but other dimensions may be used where appropriate for the application. In an exemplary embodiment, the tube  40 ,  40 ′ may have an outer diameter of approximately 3.5 inches and an interior surface  62 ,  122  which is configured and dimensioned to receive a 60 mm octagonal tube. Additionally, the tubes  40 ,  40 ′ may range from approximately one foot long to approximately 30 feet in length. The tube  40 ,  40 ′ may be formed from aluminum or an aluminum alloy (e.g., 6061 aluminum alloy (International Alloy Designation System)), however, other suitable metals, alloys or materials may be used to form the tube provided the material has sufficient strength. For example, the tube  40 ,  40 ′ may be formed from a carbon graphite reinforced polymer material. Preferably, the tube  40 ,  40 ′ may be formed by materials having a high strength to weight ratio and the ability to be manufactured using extrusion technologies. 
     Referring to  FIG. 4 , the flexible barrier material  26  may be secured to the tube  40  by a pocket of flexible barrier material  130  and rod  132  inserted within the pocket receiving channel  80 . In another alternative, the flexible barrier material  26  may be attached to a zipper  68  that is inserted into the zipper receiving channel  82 . Generally, the flexible barrier material  26  may range from approximately 1/32 of an inch in thickness to approximately ½ inch in thickness. The flexible barrier material  26  may be formed, without limitation, from natural fibers, leather, PVC, polyester, or acrylic materials. Preferably, the flexible barrier material  26  may range from approximately 7 ounces to 60 ounces in weight. In one example, the flexible barrier material  26  may be constructed from a 20 ounce vinyl fabric. In another example, the flexible barrier material  26  may be constructed from a vinyl fabric that is capable of receiving a print design. In another example, the flexible barrier material  26  may be constructed from a screen, a transparent material or a natural fabric. 
     The flexible barrier material  26  may be a single layer of material or a multilayer material formed from two or more layers of material. For example, the flexible barrier material  26  may be formed from three layers: a middle layer having enhanced sound dampening properties (e.g., mass loaded vinyl, Acoustiblok®) and two outer fabric layers (e.g., cotton, polyester, rayon, vinyl, wall paper, or wall covering material) to create an acoustic barrier. In another example, the flexible barrier material  26  may be formed from clear plastic sound blocking material. Preferably, a flexible barrier material with enhanced sound dampening properties may have a STC (Sound Transmission Class) Rating of 26 or greater. 
       FIG. 6  shows an exploded view of the idler  56  and the tube  40  of  FIG. 4 . One end  134  of the idler  56  may be inserted into the tube  40 . The opposite end  136  of the idler  56  may be mounted on the end-cap cylindrical stub  54  (not shown) to form an axis of rotation. The tube  40  may include one or more fastener alignment grooves  110 . As shown in  FIG. 7 , a drill (or fastener)  138  may be placed in a fastener alignment groove  110  to create a fastener alignment path  140  for securing the idler  56  to the tube  40 . The fastener alignment groove  110  may be located above an internal node  106  of the tube. Placement of a fastener alignment groove  110  above an internal node  106  provides a mechanism for promoting a repeatable, quick, and straightforward method of securing the idler  56  and the tube  40  with a fastener  138 . More particularly, the fastener path  140  connects the fastener alignment groove  110  and the internal node  106  of the tube. A fastener that is aligned in this manner may be expected to penetrate the tube  40  beneath the fastener alignment groove  110  and be guided by adjacent internal structural members  78  to a position above the internal node  106 . This fastener path may provide a secure connection because the fastener may be driven perpendicular to the outer surface of tube wall and through the internal node  106  before advancing into and securing the idler  56 . 
       FIG. 8  shows the left side of the flexible barrier member  26  disposed in the left side feeder-clip  48  and left side track  20  of the retractable wall system  12 . Also, the bottom of the flexible membrane barrier  26  is shown locked into the horizontal track  24 . As shown in  FIG. 8A , the left side of the flexible material barrier is fully seated within the traveling guide pin  72 . The full length square cut double pin construction  142  provides rigid reinforcement of the flexible barrier material  26  at a leading edge  144  of the sheet. As the leading edge of the sheet  144  may be subject to compressive and sheering forces as the barrier is lowered, the traveling guide pin  72  may prevent the flexible barrier material  26  from wearing, tearing, bunching or binding in the vertical track  20  when the horizontal track  24  is lowered or raised. 
     Moreover, as shown in  FIG. 9 , the traveling guide pin  72  may be configured and dimensioned to be slidably received within the rigid receiving channel  84  of the vertical track  20 . As the fasteners, which secure the flexible membrane barrier  26  to the traveling guide pin  72  are located with the rigid receiving channel  84 , they may be recessed or flush with the exterior surfaces of the traveling guide pin  72 . The zipper portion  68  of the flexible membrane barrier  26 , when disposed in the internal anchoring cavity  90 , pulls the traveling guide pin  72  into the rigid receiving channel  84  of the vertical track  20 . In this manner, the horizontal track  24  and the sides of the flexible membrane barrier  26  may be securely positioned within the left side track  20  and the right side track  22 . 
     The reinforcement of the flexible barrier material  26  and tension across the vertical tracks  20 ,  22  may increase the structural integrity of retractable wall system  12 , provide for more reliable operation of the system, and reduce mechanical fatigue of the zipper-material interface. Also, the generally uniform tension across the flexible membrane barrier  26  may increase the aesthetic appeal of the retractable wall system  12  by enhancing a uniform appearance of the flexible barrier material across the structure. Moreover, in outdoor applications, this construction may prevent drafts. In sound barrier applications, this construction may promote the deployment of a continuous sound dampening barrier and prevent fugitive sound emissions from passing individual barrier elements to reduce the effective sound dampening properties of the retractable wall system. Sound dampening material may be placed in the primary accessory receiving channel  232 , the secondary receiving channel  234 , and the arcuate receiving channels  236  as well. 
     The vertical track  20  of the retractable wall system may be secured to a structural member such as a stud or post. A pilot hole may be drilled and then a larger access hole placed in the track  20  to allow a fastener  150  to be advanced though the opposite side the track and into external structural framing  148  to securely attach the vertical track  20  to structural framing of an adjacent wall or post. 
     Referring to  FIGS. 10 and 15 , the horizontal track  24 , the left side track  20 , and the right side track  22  may share a single cross-sectional profile  152 . In  FIG. 10 , the track profile  152  is shown in use as a horizontal track  24 . In this configuration, the primary accessory receiving channel  94  may accommodate a weight bar  100 , which may be a ½ inch by ¾ inch steel bar. The weight bar  100  may be positioned within the primary receiving channel  94  by the end-cap stem blocking member  154 , the upper rail guide  156 , and the lower rail guide  158 . 
     In  FIG. 11 , the cross-sectional profile of the track  152 ′ is substantially the same as in  FIG. 10 , but a front portion  160  of the track  24 ′ is removable and forms a cover. The removable portion  160  may be secured to the track  24 ′ with snap fittings  162 . This feature allows weight bars  100  to be installed in the horizontal track  24 ′ after the retractable wall structure  12  has been erected. This may improve constructability of the system and enhance the safety of workers because handling the horizontal track with preloaded weight bars  100  is significantly heavier than handling an empty horizontal track. 
       FIGS. 10 and 11  show an elastomeric cap  164  disposed in the tertiary accessory channel  96 . Arcuate receiving channels  166 , as well as the primary and secondary accessory receiving channels  94 ,  96  may receive sound damping materials to enhance the sound dampening effect of the retractable wall system. 
       FIG. 12  shows the left feeder-clip  48  and its tapered guide hole  168 . The tapered guide hole  168  receives the zippered edge  68  of the flexible barrier material  26  as it spools off the tube (not shown). Similarly,  FIGS. 12 and 13  show the right feeder-clip  52  and its tapered guide hole  170 , which receives the zippered edge  68  of the other side of the flexible barrier material  26 . The right feeder clip  52  may further include a circular passage  172  for receiving a power cord  174  from the motor  42 . 
     Referring to  FIG. 14 , the right end-cap  50  may include a stem  176  having a rectangular channel  178 . The right side feeder-clip  52  may include a beveled top surface  180 , a central base portion  182 , and four plugs  184 ,  186 ,  187 ,  188 . One end of the feeder-clip  52  may include an elongated and corrugated plug  184 . Next to the elongated and corrugated plug  184  and disposed in the middle of the feeder-clip  52  may be a second plug  186 . The second plug  186  may be wider and shorter than the elongated corrugated plug  182 . Also, a pair of contralateral plugs  188 ,  190  may be disposed on the other side of the second plug  186 . 
     The right feeder-clip  52  may include a circular passage  172  that extends from the beveled top surface  180  through the second plug  186 . The passage  172  may be configured and dimensioned to receive an electrical cable for the motor. Additionally, the beveled top surface  180  may include a first tapered rectangular passage  170  which extends through the feeder-clip  52 . A second rectangular passage  192  may extend from the beveled top surface  180  through the feeder-clip  52  between the contralateral plugs  188 ,  190 . The first rectangular passage  170  and the second rectangular passage  192  may be separated by a thin wall  194 . The thin wall  194  may include a tapered slit  176  which extends from the top of the thin wall to the bottom of the thin wall. 
     As shown in  FIG. 15  the right feeder-clip  52  may be inserted into the rectangular channel  178  of the end-cap  50 . The stem  176  of the end-cap may be seated within the primary accessory channel  198  and may be positioned in the primary accessory channel  198  by the upper guide rail  200 , the lower guide rail  202 , and the end-cap stem blocking member  204 . The second plug  186  of the feeder-clip  52  may be received in the secondary accessory receiving channel  206 . The secondary accessory receiving channel  206  may be used to accommodate an electrical cable  174  that extends from the motor  42  to an electrical outlet outside the track. The pair of contralateral plugs  188 ,  190  may be disposed in the opposing arcuate cavities  208  at the front of the track. The traveling guide member  72  may be disposed in the rectangular receiving channel  210  of the track and the zippered end  68  of the flexible membrane barrier  26  may be disposed in the internal anchoring cavity  212 . The material connecting the zipper  68  and the flexible membrane barrier  26  may be disposed in the slot  214  between the rectangular receiving channel  210  and the internal anchoring cavity  212 . 
       FIG. 16  shows an exemplary corner assembly  216  formed from a first end-cap and track  218  and a second end-cap and track  220 . The first end-cap and track  218  and the second end-cap and track  220  may be disposed at an approximately 90 degree angle. The corner assembly  216  may be used to construct adjacent retractable wall systems, as shown in  FIG. 1 . 
       FIG. 17  shows an exemplary alignment of two tracks  22 ,  20  which may be used to construct a corner assembly  216 . In the track alignment, the alignment groove  222  in the primary accessory receiving channel  198  may be disposed opposite the tertiary accessory groove  226  of the adjacent track.  FIG. 17 a    shows how the two tracks  20 ,  32  may be securely fastened to each other. In a preferred method, a guide hole may be drilled between the upper and lower guide rails  200 ,  202  in the primary accessory receiving channel  198 . The guide hole may be enlarged to an entry hole in order to provide access to the interior of the primary accessory receiving channel. A fastener  228  may be positioned in the alignment groove  222  ( FIG. 17 ) and advanced into the tertiary accessory groove  226  ( FIG. 17 ) of the adjacent track. The enlarged hole may be covered with a plastic cap  230 . 
     Referring to  FIG. 18 , four corner assemblies  216  may be used to construct a free standing structure. The free standing structure may be formed from four (or more) retractable wall systems  240   a ,  240   b ,  240   c ,  240   d ,  240   e . Two retractable wall systems  240   c ,  240   d  may be joined together to form one side of the structure. One of the retractable wall systems  240   c  may be used as a door for the structure. 
     Referring to  FIG. 19 , a short ledge  242  may extend from the lower portion of the head rail into the enclosed space. The short ledges  242  of opposing retractable wall systems  240   b ,  240   e  may be used to support beams  244 , which may form a cover for the structure  238 . The beams may be used to form a continuous cover or a lattice cover. For example, wood boards (e.g., 1″×2″ or 2″×4″ boards) may be supported by the head rail ledges to form a lattice cover, which may allow the structure to be used as a temporary booth (or Sukkah) that is constructed for use during the Jewish festival of Sukkot. 
     Referring to  FIG. 20 , the retractable wall system may be adapted for use as an awning  246 . A webbing material may  248  be molded to the flexible membrane barrier  250  that forms the awning cover in order to make the canopy stronger while maintaining light weight. The awning  246  may include a side pennant  252 . As shown, in  FIG. 21 , the side track of the retractable wall system may be modified such that the side frame  254  incorporates a reinforced flexible membrane barrier connection  256  to provide a taunt but retractable ceiling canopy. The side frame  254  may include a roller track  258  for a wheel  260  which is connected to the front crossbar  262 . Also, the side frame  254  may include a gutter  264  for collecting and transporting rain water  266 . An exterior groove  268  on the side frame may be used to house a sealant for sealing the frame to a structure or an abutting awning frame. 
     As depicted in  FIGS. 21-23 , a reinforced flexible membrane barrier connection  256  may be used to deploy a side pennant  252  with the ceiling canopy. Referring to  FIG. 23 , the front cross bar  262  may support a bracket  270  that holds a loop of canopy material  272  to form a pocket to collect and direct rain water  266  to the gutter  264 . The front partition  274  of the awning structure  246  may include a channel  276  for receiving water from the gutter. In another embodiment, the gutter and wheel track may the same structure. The front partition  274  further may include a solenoid  278  that may be used to lock the awning in the deployed configuration. Additionally, a brake (not shown) may be available on the motor end and the non-motor end of the awning spool. The retractable wall system may be constructed from materials selected to better withstand changes in temperature, corrosion, or degradation from ultraviolet light. 
     While it has been illustrated and described what at present are considered to be preferred embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Additionally, features and/or elements from any embodiment may be used singly or in combination with other embodiments. Therefore, it is intended that this invention not be limited to the particular embodiments disclosed herein, but that the invention include all embodiments falling within the scope and the spirit of the present invention.