Patent Publication Number: US-6705338-B2

Title: Collapsible structures

Description:
RELATED CASES 
     This is a continuation of Ser. No. 09/313,147, filed May 17, 1999, entitled “Collapsible Play Structures”, now U.S. Pat. No. 6,360,761, which is in turn a continuation-in-part of co-pending Ser. No. 09/162,086, filed Sep. 29, 1998, now abandoned which is a division of Ser. No. 08/859,876, entitled “Collapsible Play Structures”, filed May 21, 1997, now U.S. Pat. No. 5,816,279, which is a division of Ser. No. 08/627,875, entitled “Collapsible Play Structures”, filed Apr. 3, 1996, now U.S. Pat. No. 5,664,596, which is a continuation of Ser. No. 08/281,369, entitled “Collapsible Play Structures”, filed Jul. 27, 1994, now U.S. Pat. No. 5,560,385, which is a continuation-in-part of Ser. No. 08/024,690, entitled “Collapsible Shade Structure”, filed Mar. 1, 1993, now U.S. Pat. No. 5,467,794, which is in turn a continuation-in-part of Ser. No. 07/764,784, entitled “Collapsible Shade Structure”, filed Sep. 24, 1991, now U.S. Pat. No. 5,301,705, the entire disclosures of which are incorporated by this reference as though set forth fully herein. This is also a continuation-in-pad of co-pending Ser. No. 09/802,227, filed Mar. 8, 2001, entitled “Collapsible Structures”, which is a continuation of Ser. No. 09/541,211. filed Apr. 3, 2000, entitled “Collapsible Structures”, now U.S. Pat. No. 6,209,557, which is a continuation of Ser. No. 09/059,811, filed Apr. 14,1998, entitled “Collapsible Structures”, now U.S. Pat. No. 6,155,281, which is a continuation-in-part of Ser. No. 08/773,066, filed Dec. 26, 1996, entitled “Collapsible Structures”, now U.S. Pat. No. 5,778,915, the entire disclosures of which are incorporated by this reference as though set forth fully herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to collapsible structures, and in particular, to collapsible structures which may be provided in a variety of shapes and sizes. The collapsible structures may be twisted and folded to reduce the overall size of the structures to facilitate convenient storage and use. 
     2. Description of the Prior Art 
     Collapsible objects have recently become popular with both adults and children. Many of these collapsible objects have a plurality of panels which may be twisted and folded to reduce the overall size of the object to facilitate convenient storage and use. Each panel is comprised of a fabric or material that is supported by a resilient frame member, with the fabric or material spanning a portion of, or entirely across, the area supported by the frame member. The frame member supports the periphery of each panel, and is capable of being twisted and folded to reduce the size of each panel. 
     Examples of such collapsible objects are shown and described in U.S. Pat. No. 5,467,794 (Zheng), U.S. Pat. No. 5,560,385 (Zheng) and U.S. Pat. No. 5,778,915 (Zheng) in the form of collapsible structures. These structures are currently being enjoyed by many people in many different applications. For example, these structures have been provided in many different shapes and sizes for children&#39;s play indoors and outdoors. Smaller versions of these structures have been used as infant nurseries. Even smaller versions of these structures have been used as dollhouses and action figure play houses by toddlers and children. As another example, these structures have been made into tents or outdoor structures that can be used by adults and children for camping or other outdoor purposes. These structures have also been used as beach cabanas. Even animals can enjoy these structures. Some of these structures have been made into shelters that can be used by pets, both indoors and outdoors. 
     The wide-ranging uses for these collapsible structures can be attributed to the performance, convenience and variety that these structures provide. When fully expanded, these structures are stable and can be used as a true shelter without the fear of collapse. These structures are easily twisted and folded into a compact configuration to allow the user to conveniently store the structures. The light-weight nature of the materials used to make these structures makes it convenient for them to be moved from one location to another. These structures also provide much variety in use and enjoyment. For example, a child can use a structure both indoors and outdoors for different play purposes, yet can use the same structure for camping. 
     Another example of collapsible objects include collapsible game and play structures, such as those illustrated in U.S. Pat. No. 5,722,446 (Zheng) and U.S. Pat. No. 5,816,954 (Zheng). These structures provide a multitude of game structures that can be enjoyed by children and adults indoors and outdoors. 
     SUMMARY OF THE DISCLOSURE 
     It is an object of the present invention to provide collapsible objects and structures that are different from those mentioned above, and which offer the user different variety of play and use. 
     In order to accomplish the objects of the present invention, the collapsible structure according to the present invention has at least four panels, including a bottom panel, a first panel, a second panel and a third panel. Each panel has a foldable frame member having a folded and an unfolded orientation, with a fabric material covering portions of the frame member to form the panel when the frame member is in the unfolded orientation. The fabric assumes the unfolded orientation of the frame member. Each panel further includes a first side and a second side, with the first side of one panel coupled to the second side of an adjacent panel, and with the bottom panel resting on the surface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a collapsible structure according to one embodiment of the present invention; 
     FIG. 1A is a partial cut-away view of the section A of the structure of FIG. 1 illustrating a frame member retained within a sleeve; 
     FIG. 2A is a cross-sectional view of a first preferred connection between two adjacent panels of the structure of FIG. 1 taken along line  2 — 2  thereof; 
     FIG. 2B is a cross-sectional view of a second preferred connection between two adjacent panels of the structure of FIG. 1 taken along line  2 — 2  thereof; 
     FIGS.  3 (A) through  3 (E) illustrate how the collapsible structure of FIG. 1 may be twisted and folded for compact storage; 
     FIGS. 4-6 illustrate modifications that can be made to the structure of FIG. 1; 
     FIG. 7 is a perspective view of a collapsible structure according to another embodiment of the present invention; 
     FIG. 8 is a perspective view of a collapsible structure according to yet another embodiment of the present invention; 
     FIG. 9 is a perspective view of a collapsible structure according to a further embodiment of the present invention; 
     FIG. 10 is an exploded perspective view of the structure of FIG. 9; 
     FIG. 11 is an exploded perspective view illustrating how two end panels can be deployed with the structure of FIG. 1; and 
     FIG. 12 is a perspective view illustrating the two end panels of FIG. 11 assembled with the structure of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following detailed description is of the best presently contemplated modes of carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating general principles of embodiments of the invention. The scope of the invention is best defined by the appended claims. 
     FIGS. 1 and 1A illustrate a possible basic component for a collapsible structure according to the present invention which takes the form of a module  20 . As explained in greater detail hereinbelow, the collapsible structures according to the present invention can each be comprised of one or more of these modules  20  assembled to create a resulting structure having the desired shape and size. 
     Referring to FIG. 1, according to a first preferred embodiment of the present invention, each module  20  comprises four panels  22 ,  24 ,  26  and  28  connected to each other to encircle an enclosed space. The four panels include a bottom panel  22 , two side panels  24 ,  26 , and a top panel  28 . Each panel  22 ,  24 ,  26  and  28  has four sides, including a first side  30 , a second side  32 , a third side  34  and a fourth side  36 . The first side  30  of each panel is hingedly coupled to the third side  34  of each adjacent panel to form the module  20 . 
     Referring to FIG. 1A, each panel  22 ,  24 ,  26  and  28  has a continuous frame retaining sleeve  38  provided along and traversing the four edges of its four sides  30 ,  32 ,  34 ,  36 . A continuous frame member  40  is retained or held within each frame retaining sleeve  38  to support each panel  22 ,  24 ,  26  and  28 . Each sleeve  38  may be formed by folding a piece of fabric and applying a stitching  46 . Only one frame member  40  is shown in FIG. 1A; the other frame members are not shown but are the same as frame member  40 . The frame members  40  may be merely retained within the respective frame retaining sleeves  38 , without being connected thereto. Alternatively, the frame retaining sleeves  38  may be mechanically fastened, stitched, fused, or glued to the frame members  40  to retain them in position. 
     The continuous frame members  40  may be provided in the form of one continuous loop, or may comprise a strip of material connected at both ends to form a continuous loop. The continuous frame members  40  are preferably formed of flexible coilable steel having a memory, although other materials such as plastics may also be used. The frame members should be made of a material which is relatively strong and yet is flexible to a sufficient degree to allow it to be coiled. Thus, each frame member  40  is capable of assuming two positions or orientations, an open or expanded position such as shown in FIG. 1, or a folded position in which the frame member is collapsed into a size which is much smaller than its open position (see FIG.  3 E). 
     Fabric or sheet material  42  extends across each panel  22 ,  24 ,  26  and  28  and is held taut by the respective frame members  40  when in its open position. The fabric  42  for the corresponding panel  22 ,  24 ,  26  or  28  is stitched to the sleeve  38 . The fabric  42  can extend completely across the panel to entirely cover the space enclosed by the frame member  40 , or can extend across selected portions of the space enclosed by the frame member  40 . The term fabric is to be given its broadest meaning and should be made from strong, lightweight materials and may include woven fabrics, sheet fabrics or even films and meshed materials. For example, the fabric  42  in FIG. 1 is illustrated as being a meshed material. The fabric should be water-resistant and durable to withstand the wear and tear associated with rough treatment by children. 
     FIG. 2A illustrates one possible connection for connecting adjacent edges of two panels  26  and  28 . The fabric pieces  42  are stitched at their edges to their respective sleeves  38  by a stitching  44 . The stitching  44  also acts as a hinge for the panels  26  and  28  to be folded upon each other, as explained below. The connections for the three other pairs of adjacent edges may be identical. Thus, the connections on the first side  30  and the third side  34  of each panel  22 ,  24 ,  26  and  28  act as hinge connections for connecting an adjacent panel. 
     The stitching  44  is essentially the same as stitching  46  illustrated in FIG. 1A, in that both stitchings  44  and  46  also operate to enclose the fabric material to form the sleeve  38 . The difference is that stitching  44  extends along the first and third sides  30  and  34  (where a hinge connection is present) and also operates to attach adjacent panels, while stitching  46  merely extends along the second and fourth sides  32  and  36  (where there is no hinge connection). 
     FIG. 2B illustrates a second possible connection for connecting adjacent edges of two panels  26  and  28 . The frame retaining sleeves  38  at the first side  30  of panel  26  and the third side  34  of panel  28  converge at, or are connected to, one sleeve portion which interconnects panels  26  and  28  to form a singular frame retaining sleeve  48  which retains the frame members  38  for panels  26 ,  28 . Sleeve  48  may be formed by providing a tubular fabric, or by folding a piece of fabric, and applying a stitching  50  to its edges to connect the sleeve  48  to the fabric  42  for panels  26 ,  28 . Stitching  50  also acts as a hinge for the panels  26 ,  28 . The connections for the three other pairs of adjacent edges may be identical. 
     The module  20  can be deployed with the bottom panel  22  resting on the floor or other surface, and with the side panels  24 ,  26  functioning as side walls. When deployed in this manner, two side openings are defined: a first side opening that is defined by the second side  32  of the panels  22 ,  24 ,  26 ,  28 , and a second side opening that is defined by the fourth side  36  of the panels  22 ,  24 ,  26 ,  28 . 
     As shown in FIG. 1, an optional side panel  60  can be provided to cover the first side opening. The side panel  60  can have the same construction as side panels  24 ,  26 , and can have a third side  62  hingedly coupled to the second side  32  of the side panel  24  using either of the techniques illustrated in FIGS. 2A or  2 B. Alternatively, as shown in FIG. 4, the side panel  60  can be removably coupled to the second side  32  of the panels  22 ,  24 ,  26 ,  28  (i.e., the first side opening) by utilizing one or more detachable connectors or removable attachment mechanisms  64  (referred to herein as “attachment mechanisms”), such as opposing Velcro pads, hooks, ties or similar mechanisms. These attachment mechanisms  64  can even be provided on the panels  22 ,  24 ,  26 ,  28  (as shown in FIG. 4) to engage the corresponding attachment mechanisms  64  on the side panel  60 . Any number of the sides of the panel  60  can be coupled to the second sides  32  of the panels  22 ,  24 ,  26 ,  28  in the module  20 . However, if only one side (e.g.,  62  as shown in FIG. 1) of the side panel  60  is coupled to the second side  32  of one of the panels  22 ,  24 ,  26 ,  28 , the side panel  60  can be used as a door or end panel that can be pivoted about the hinge connection between sides  32  and  62 . 
     The panel  60  can be provided as a support mechanism to support the module  20  in the upstanding configuration shown in FIG.  1 . Therefore, it is possible to couple as many sides of the panel  60  to the second side  32  of as many different panels  22 ,  24 ,  26 ,  28  as desired, some in either a permanent manner (i.e., using the techniques shown in FIGS. 2A or  2 B) or in a removable manner (i.e., using removable attachment mechanisms  64 ). For example, the panel  60  can have different sides coupled to the second side  32  of all four panels  22 ,  24 ,  26 ,  28  to provide an end wall for supporting the four panels  22 ,  24 ,  26 ,  28  in the upstanding configuration. 
     It is also possible to provide support mechanisms other than the panel  60  for supporting the module  20  in the upstanding configuration shown in FIG.  1 . For example, straps  58  can be tied between the second sides  32  of adjacent panels, or between the fourth sides  36  of adjacent panels. These straps  58  help to maintain the generally perpendicular orientation between adjacent panels, since the straps  58  can be provided at selected lengths and at selected positions along the second sides  32 , for example, so that two adjacent panels cannot be pivoted so that the angle between adjacent panels extends beyond 90 degrees. The straps  58  can have opposing ends that are stitched, or removably attached (e.g., by a removable attachment mechanism) to the sides  32  or  36  of the panels. 
     As a further alternative to the panel  60  and the straps  58 , a fabric corner piece  59  can be attached to either the second sides  32  or the fourth sides  36  of adjacent panels for supporting the module  20  in the upstanding configuration shown in FIG.  1 . Other alternative support mechanisms can be possible, with the common feature for such support mechanisms being that they function to couple two or more sides of adjacent panels to limit the extend to which adjacent panels can pivot. 
     FIGS. 3A through 3E describe the various steps for folding and collapsing the structure or module  20  of FIG. 1 for storage. If panel  60  is removable, it can be first removed. Then, as shown in FIG. 3A, the first step consists of pushing in panels  26  and  28  about the hinged connections such they collapse against panels  22  and  24 , respectively. Then, in the second step shown in FIG. 3B, two panels  24  and  28  are folded about the hinged connections so as to be collapsed upon the other two panels  22  and  26  to create a stack of four panels  24 ,  28 ,  26 ,  22  (in this order). The stack of panels is then twisted and folded to collapse the frame members and panels into a smaller shape. In the third step shown in FIG. 3C, the opposite border  52  of the combined stack of panels is folded in upon the previous fold to further collapse the frame members with the panels. As shown in FIG. 3D, the fourth step is to continue the collapsing so that the initial size of the stack of panels is reduced. FIG. 3E shows the fifth step with the frame members and panels collapsed on each other to provide for a small essentially compact configuration having a plurality of concentric frame members and layers of the panels so that the collapsed module  20  has a size which is smaller than the initial size of the panels. 
     The optional panel  60 , if removable, can be placed on top of the stack of four panels  24 ,  28 ,  26 ,  22  in FIG. 3B, and twisted and folded together as a stack of five panels  60 ,  24 ,  28 ,  26 ,  22 . If the optional panel  60  is stitched to the module  20 , then it can be folded about its hinged connection to its adjacent panel  22 ,  24 ,  26  or  28  (e.g., folded against panel  24  for the embodiment of FIG. 1 in the direction of arrow A 1 ), and then twisted and folded together as a stack of five panels  60 ,  24 ,  28 ,  26 ,  22 . 
     To re-open the module  20  to its expanded configuration, the combined stack of panels is unfolded. The memory (i.e., spring-load) of the frame members will cause the frame members to uncoil on their own and to quickly expand the panels to their expanded configuration shown in FIG.  3 B. The same principle can be applied to re-open all the other embodiments of the present invention. 
     FIG. 5 illustrates a possible modification to the modules  20  shown in FIGS. 1 and 4. Here, the side panel  60  is illustrated as having its bottom side  66  hingedly coupled to second side  32  of bottom panel  22 . Attachment mechanisms  64  can be provided on the top side  68  of side panel  60  for securing the top side  68  to second side  32  of top panel  28 . In addition, another side panel  70  can be provided to cover the second side opening of the module  20 . Side panel  70  has its top side  72  hingedly coupled to fourth side  36  of top panel  28 , and attachment mechanisms  64  can be provided on the bottom side  74  of the side panel  70  for securing its bottom side  68  to fourth side  36  of bottom panel  22 . The side panels  60  and  70  can be used to support the module  20  in the upstanding configuration. The configuration shown in FIG. 5 can be folded and collapsed according to the principles illustrated in FIGS. 3A-3E. 
     While the module  20  of FIG. 1 is shown and described as having four side panels, each having four sides, it will be appreciated that a module may be made of any number of panels, each having any number of sides, without departing from the spirit and scope of the present invention. For example, each module may have two or more panels, and each panel may have three or more sides. Thus, the module of the present invention may take a variety of external shapes. However, each panel of the module, regardless of its shape, is supported by at least one continuous frame member. 
     One example of modules having panels with different shapes is shown in FIG. 6, which illustrates a module  20   a  containing modifications to the module  20  of FIG.  1 . The elements of the module  20   a  that are the same as the elements of the module  20  are provided with the same numeral designations except that an “a” has been added to the numeral designations in FIG.  6 . In particular, the panels  22   a ,  24   a ,  26   a ,  28   a ,  60   a  are the same as panels  22 ,  24 ,  26 ,  28 ,  60  except that the bottom panel  22   a  is larger than the top panel  28   a . In addition, the sides  32   a  and  36   a  of the side panels  24   a ,  26   a  are angled upwardly so that (1) the bottom side  30   a  of side panel  24   a  and bottom side  34   a  of side panel  26   a  have the same length as the sides  34   a  and  30   a , respectively, of the bottom panel  22   a , and (2) the top side  34   a  of side panel  24   a  and top side  30   a  of side panel  26   a  have the same length as the sides  30   a  and  34   a , respectively, of the top panel  28   a . Side panel  60   a  has its top side  68   a  hingedly coupled to second side  32   a  of the top panel  28   a , and attachment mechanisms  64   a  can be provided on the bottom side  66   a  of the side panel  60   a  for securing its bottom side  66   a  to the second side  32   a  of the bottom panel  22   a . The configuration shown in FIG. 6 can be folded and collapsed according to the principles illustrated in FIGS. 3A-3E. Thus, the module  20   a  defines a dome-like structure having a wider base. 
     As another non-limiting example, FIG. 7 illustrates a module  20   b  containing modifications to the modules  20  and  20   a . The elements of the module  20   b  that are the same as the elements of the module  20  are provided with the same numeral designations except that a “b” has been added to the numeral designations in FIG.  7 . In particular, the panels  22   b ,  24   b ,  26   b ,  28   b ,  60   b  are the same as panels  22 ,  24 ,  26 ,  28 ,  60  except that the second side  32   b  of each panel  22   b ,  24   b ,  26   b ,  28   b  is longer than the fourth side  36   b  of each panel, and the first side  30   b  and third side  34   b  of each panel  22   b ,  24   b ,  26   b ,  28   b  are angled to facilitate the differences in length between the second and fourth sides  32   b ,  36   b , respectively. Side panel  60   b  has its side  62   b  hingedly coupled to second side  32   b  of panel  24   b , like in FIG.  1 . The configuration shown in FIG. 7 can be folded and collapsed according to the principles illustrated in FIGS. 3A-3E. Thus, the module  20   b  defines a structure having a wider opening or door (e.g., embodied in the form of panel  60   b ) that narrows inwardly. A panel  70   b  that is smaller than panel  60   b  can be coupled to the fourth side  36   b  of one or more panels  22   b ,  24   b ,  26   b ,  28   b  using any of the coupling techniques illustrated above. The panel  70   b  can be used as another door, or as an end wall for the module  20   b , or to provide further support to the module  20   b.    
     Module  20   b  in FIG. 7 illustrates other possible alternatives and modifications. For example, the fabric  42   b  of panel  60   b  only extends along a portion (e.g., the top half) of the panel  60   b . At the bottom corners of panel  60   b  are provided straps or corner pieces  78  that have opposing ends attached (e.g., by stitching) to adjacent sides of the panel  60   b . The straps or corner pieces  78  operate to define the configuration of the panel  60   b  at these corners (i.e., to define the generally right-angled corners in panel  60   b ). Such straps or corner pieces  78  can be utilized in lieu of fabric pieces  42  for any of the panels of the present invention. For example, corner pieces  78  of fabric are also provided for bottom panel  22   b , and for panel  60  in FIG.  4 . The corners defined by these corner pieces  78  can have any angle (including a right angle or 90 degrees) but the angle depends on the configuration of the rest of the panel and the number of corner pieces  78  for that panel. For example, the provision of three corner pieces  78  without any fabric  42  will define a triangular panel, the provision of four corner pieces  78  without any fabric  42  will define a generally square or rectangular panel, the provision of five corner pieces  78  without any fabric  42  will define a generally polygonal or five-sided panel, and so on. Each of these panel configurations (i.e., triangular, square, polygonal) will have corners that have different angles. 
     To further illustrate the flexibility and variety of the principles of the present invention, FIG. 8 illustrates a structure  100  having six panels  102 ,  104 ,  106 ,  108 ,  110  and  112 , each panel having the same construction as the panels  22 ,  24 ,  26 ,  28  in FIG.  1 . As with module  20 , the first side  114  of each panel is hingedly coupled to the third side  116  of each adjacent panel to form the module  100 . A side panel  120  having six sides (one for each panel of the structure  100 ) may be attached to a second side  122  of the top panel  108  by either a hinged connection such as those illustrated in FIGS. 2A or  2 B, or by a removable attachment mechanism. One or more of the other sides of the panel  120  can also be coupled (either through a hinged or removable connection) to the second side  122  of one or more of the other panels  102 ,  104 ,  106 ,  108 ,  110 ,  112 . Thus, the structure  100  essentially consists of an assembly of six panels that are arranged in a circular orientation. The panel  120  operates to hold the structure  100  in the upstanding configuration. 
     The structure  100  can be folded and collapsed by first folding panels  108 ,  110 ,  112  on top of panels  106 ,  104 ,  102 , respectively. The panels are then folded to create a stack of six panels that can be folded and collapsed according to the principles illustrated in FIGS. 3B-3E. 
     The structure  130  in FIGS. 9 and 10 illustrate how two modules  20  can be combined to create a larger or different structure  130 . The structure  130  essentially consists of two separate modules  20   c  and  20   d , each having the same construction as module  20 . The elements of the modules  20   c  and  20   d  that are the same as the elements of the module  20  are provided with the same numeral designations except that a “c” or “d” has been added to the numeral designations in FIGS. 9 and 10. The second side  32   c  of each panel  22   c ,  24   c ,  26   c ,  28   c  of module  20   c  is coupled to the fourth side  36   d  of each panel  22   d ,  24   d ,  26   d ,  28   d  in module  20   d . This coupling can be accomplished by using either of the connections illustrated in FIGS. 2A or  2 B, or by using removable attachment mechanisms  64   c  and  64   d  as illustrated in FIG.  10 . 
     In addition, an optional support panel  132  can be provided, with its sides  134 ,  136 ,  138 ,  140  coupled (by either of the connections illustrated in FIGS. 2A or  2 B, or by using removable attachment mechanisms) to the second side  32   c  of each panel  22   c ,  24   c ,  26   c ,  28   c  of module  20   c  and the fourth side  36   d  of each panel  22   d ,  24   d ,  26   d ,  28   d  in module  20   d . Support panel  132  provides internal stability and support for the connection or coupling of the two modules  20   c ,  20   d . In addition, by coupling a plurality of modules  20  together, one can create a tunnel or other passageway if the panel  132  is not provided, or if an opening  133  is provided in the panel  132  (see FIG.  10 ). 
     As an alternative to the support panel  132 , any of the support mechanisms described above can be provided along the second sides  32   c  or  32   d  and fourth sides  36   c  or  36   d . For example, as shown in FIGS. 9 and 10, these support mechanisms can take the form of the straps  58   c  or  58   d  described above. 
     Structure  130  can be disassembled and collapsed according to the principles set forth above in connection with FIGS. 3A-3E. If modules  20   c ,  20   d  can be detached, then each module  20   c ,  20   d  can be folded and collapsed separately, with support panel  132  placed on top of the stack of panels of either module  20   c  or  20   d  and then folded and collapsed together as a combined stack. Alternatively, the two stacks of panels  22   c ,  24   c ,  26   c ,  28   c  and  22   d ,  24   d ,  26   d ,  28   d  can be placed on top of each other (together with support panel  132 ), and the stack of nine panels folded and collapsed together. If the modules  20   c ,  20   d  are hingedly stitched together, then panels  24   c ,  24   d ,  28   c ,  28   d  can be folded on to panels  22   c ,  22   d ,  26   c ,  26   d , respectively, then combined panels  28   c ,  28   d ,  26   c ,  26   d  can be folded on to combined panels  24   c ,  24   d ,  22   c ,  22   d . Thereafter, the panels  22   d ,  24   d ,  26   d ,  28   d  of panel  20   d  are folded about the hinged connection along sides  32   c  and  36   d  to rest against the panels  22   c ,  24   c ,  26   c ,  28   c  of panel  20   c  to create a stack of eight panels that can be folded and collapsed according to FIGS. 3B-3E. 
     The first and second side openings created by the modules  20  according to the present invention can be used for many purposes. As illustrated in FIGS. 9 and 10, they can be used as openings to provide ingress to and egress from a tunnel-like structure. Another example is illustrated in FIGS. 11 and 12, where end panels  142  and  144  are provided to support the module  20  at the first and second side openings. Each end panel  142  and  144  has the same construction as any of the panels  22 ,  24 ,  26 ,  28 , except that each end panel  142 ,  144  can have a different shape and size. For example, end panel  142  has a larger square or rectangular shape, while end panel  144  has a larger size and shorter top side  146  and longer bottom side  148 . In addition, each end panel  142 ,  144  has an opening  150 ,  152 , respectively, provided in its fabric piece  154 ,  156 , respectively. Each opening  150 ,  152  is sized and configured to match the size and configuration of the first and second side openings of the module  20 . Attachment mechanisms  158  can be provided along the periphery of these openings  150 ,  152  and/or the first and second side openings of the module  20  to couple the end panels  142 ,  144  to the module  20 . The assembled structure is shown in FIG.  12 . 
     Thus, the embodiments of the present invention increase the applications and utility of the collapsible structures to provide the user with an unlimited source and variety of fun and entertainment. The shapes and sizes of the panels and the structures can be varied or combined, as well as the entertainment features. These embodiments further illustrate the versatility of the basic modules  20  of the present invention, in that these basic modules  20  can be used to form the basis for numerous structures that offer an unlimited variety of entertainment and other purposes. 
     While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.