Patent Publication Number: US-6658800-B2

Title: Polygon-shaped structural panel and construction method for geodesic domes

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This non-provisional application claims benefit of U.S. Patent Provisional Application Serial No. 60/243,075, entitled “Structural Design System and Construction Methods for Geodesic Domes and Conventional Structures,” filed on Oct. 25, 2000. 
    
    
     FIELD OF INVENTION 
     The present invention is directed to a method and structural component for use in constructing geodesic domes, and more particularly, the invention is directed to a method and structural component for constructing a geodesic dome using standardized polygon-shaped panels. 
     BACKGROUND ART 
     A geodesic dome structure is typically formed from numerous lightweight interlocking polygon-shaped bodies. Although the overall shape of the dome is spherical, the individual bodies are often flat panels. Since the geodesic dome was developed and disclosed in U.S. Pat. No. 2,682,235 to Fuller, geodesic dome construction has become well-known in the art. Due to certain inherent advantages of domes, various commercial applications have been developed. Domes are often a desirable construction method for temporary housing, vacation homes, emergency shelters, or remote work sites. Despite the adoption of the geodesic dome as a construction method, concerns with their design have limited their wide-spread use. 
     Existing dome construction methods and structures share common design goals. Structural strength, cost, ease in assembly, and the ability to weatherproof are desired features. Since domes are often constructed at remote sites, maintaining a simple bill of materials is also advantageous for shipping, inventory, and maintenance concerns. 
     Many dome designs use multiple polygon-shaped panels connected by various means. Several prior art patents teach the use of triangle-shaped panels. The panels may be joined by wire mesh to form a geodesic dome, or assembled within elongated rods which form the geodesic structure. Other connecting methods include adhesive tape and conventional hardware. These proposals teach using planar panels and forming the dome curvature by the panel connection means. The triangular panels are typically flat and often nearly equilateral. 
     The prior art fails to disclose a geodesic dome construction apparatus and method in which a dome may be substantially constructed from an inventory of a limited number of structural convex panel sizes utilizing a single connection means. A panel design suitable for use in building a geodesic dome that provides a simple and reliable connection technique is needed in order to simplify the process of dome construction. 
     SUMMARY OF THE INVENTION 
     The present invention provides a method and structural component for constructing a geodesic dome using standardized polygon-shaped panels. The invention allows for the use of a minimum set of components to substantially construct a large geodesic dome. Practice of the invention reduces transportation, inventory, and handling expense. Procurement, assembly, and maintenance complexity for the end user is also reduced. 
     A structural component panel, constructed in accordance with an exemplary embodiment of the invention, has a polygon-shaped body having an outer surface and an inner surface. The panel further includes a plurality of panel edges such that at least one edge includes a lip seam edge suitable for mating with an adjacent panel edge of a corresponding panel, and a plurality of panel corners defined by the intersection of the panel edges. A plurality of axes are formed such that each said axis leads from a first panel corner to a second panel corner, wherein the second panel corner does not share a common panel edge with said first panel corner. 
     In one embodiment of the invention, the outer surface of the panel comprises a compound convex curvature. The curvature is such that an integrated assembly of a plurality of the panels substantially forms a geodesic dome structure, wherein a majority of the panels are uniform in shape and size. The panel edges include two or more primary edges and two or more secondary edges, such that the primary edges are longer than the secondary edges, wherein at least one primary edge and at least one secondary edge forms a lip seam edge. The lip seam edge includes an inwardly disposed lip forming a mating surface suitable for mating with an adjacent straight seam edge of a corresponding panel so that the engagement between the two forms a seal. The seal may be made to impede moisture by various fastening methods, including screwing, riveting, gluing, taping or welding. 
     In another embodiment of the invention, the panel is a kite-shaped quadrilateral. The axes of the kite-shaped panel include a primary axis and a secondary axis, such that the primary axis intersects a corner defined by the intersection of two primary edges. The panel may be symmetric with respect to the primary axis. 
     A method of constructing a geodesic dome structure is another aspect of the invention. The method includes the steps of selecting a plurality of uniformly shaped construction panels, mating a panel edge of a first panel to a panel edge of a second panel such that a seal is formed, fastening the seal to impede moisture by a fastening method, mating a panel edge of a third panel to a panel edge of the second panel such that a seal is formed and fastened, and repeating the mating and fastening steps, such that a geodesic dome structure is substantially formed. 
    
    
     These and other objects, advantages and features of the invention will become better understood by review of the accompanying detailed description of the best mode of carrying out the invention which is described in conjunction with the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of a kite panel constructed in accordance with one embodiment of the present invention; 
     FIG. 2A is a vertical cross-sectional view of the kite panel shown in FIG. 1; 
     FIG. 2B is a vertical cross-sectional view of a kite panel constructed in accordance with an alternative embodiment; 
     FIG. 2C is a vertical cross-sectional view of the kite panel constructed in accordance with a second alternative embodiment; 
     FIG. 2D is a vertical cross-sectional view of the kite panel constructed in accordance with a third alternative embodiment; 
     FIG. 3A is a schematic view of one base combination of prior art panels; 
     FIG. 3B is a schematic view of one base combination of panels constructed in accordance with one embodiment of the present invention; 
     FIG. 4A is a schematic view of another base combination of prior art panels; 
     FIG. 4B is a schematic view of one combination of panels constructed in accordance with an alternative embodiment of the present invention; 
     FIG. 5 is a plan view of a geodesic dome substantially constructed from a group of standardized kite panels as shown in FIGS. 1,  2 A and  3 B; and 
     FIG. 6 is a perspective view of the geodesic dome shown in FIG.  5 . 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     The disclosed exemplary embodiment of the present invention addresses the need for an improved structural component panel and method for use in constructing a geodesic dome structure. The improved structural component panel allows for a reduced number of common panel types, less total panels, and reduced material and construction costs. 
     Referring now to the drawings, a plan view of a component panel  10  constructed in accordance with one embodiment of the present invention is illustrated in FIG.  1 . As illustrated, the panel  10  comprises a polygon-shaped body  12 , a plurality of panel edges  14   a ,  14   b ,  14   c ,  14   d , and a plurality of panel corners  16   a ,  16   b ,  16   c ,  16   d.    
     The polygon-shaped body  12  as illustrated is generally kite-shaped. It will be apparent to others skilled in the art that many other suitable polygon shapes can be utilized in light of this disclosure. The polygon-shaped body  12  includes an outer surface  20  and an inner surface  22 , best shown in FIG.  2 A. 
     Referring again to FIG. 1, the plurality of panel edges  14   a,    14   b,    14   c,    14   d  include at least one edge having a lip seam edge suitable for mating with an adjacent straight panel edge of a corresponding panel. As illustrated, two panel edges  14   a,    14   b  include a lip seam edge and two panel edges  14   c,    14   d  include a straight edge. As illustrated in FIG. 2A, a lip seam edge includes a shoulder portion  24  generally perpendicular to the outer surface  20  and a lower inwardly disposed lip surface  26  generally perpendicular to the shoulder portion  24 . As illustrated in FIG. 2A, the length of the shoulder portion  24  is about the same as the thickness of the panel. The inwardly disposed lip surface  26  is adapted to sealingly mate with an adjacent straight edge of a corresponding panel to form a seal. 
     As stated, a plurality of panel corners  16   a,    16   b,    16   c,    16   d  are defined by the intersections formed by the four panel edges  14   a,    14   b,    14   c,    14   d.  As illustrated in FIG. 1, a plurality of axes P 1 , P 2  are formed. Each axis leads from a first panel corner to a second panel corner, wherein the second panel corner does not share a common panel edge with the first panel corners illustrated, P 1  is a primary axis and P 2  is a secondary axis. The panel  10  as illustrated is a kite-shaped quadrilateral  12 . The quadrilateral  12  is symmetric with respect to the primary axis P 1 . 
     The primary axis P 1  intersects a corner defined by the intersection of two primary edges  14   a,    14   c  and a corner defined by the intersection of two secondary edges  14   b,    14   d.  In the embodiment illustrated in FIG. 1, the panel  10  includes two primary edges  14   a,    14   c  and two secondary edges  14   b,    14   d.  The primary edges are longer than the secondary edges in the illustrated embodiment. At least one primary edge  14   a  and at least one secondary edge  14   b  form a lip seam edge. 
     FIG. 2A is a cross-sectional view of the panel  10  shown in FIG.  1 . The outer surface  20  of the panel is convex shaped and the inner surface  22  is concave shaped. It will be apparent to others skilled in the art that many other suitable panel outer surface shapes can be utilized in light of this disclosure. For purposes of example only, the outer surface may include a compound convex curvature. In other words, the radius bend of the panel along the longer primary axis P 1  may be unequal to the radius bend of the panel along the shorter secondary axis P 2 . 
     FIG. 2B is a cross-sectional view of a panel  30  constructed in accordance with an alternative embodiment. The panel  30  includes a plurality of structural ribs  32 . As illustrated, three structural ribs are shown, however, any suitable number may be utilized. Each structural rib  32  protrudes from the inner surface  34  of the panel  30 . The ribs  32  lead substantially from a first pane edge to a second panel edge, (for example, in FIG. 1, panel edges  14   a,    14   b ) wherein the second panel edge does not share a common panel corner with the first panel edge. The ribs  32  generally act to give the panel increased structural strength, as compared to the panel  20  illustrated in FIG.  2 A. As illustrated, the outer surface  36  is without ribs but ribs may be disposed on the outer surface  36  as well. 
     FIG. 2C is a cross-sectional view of a panel  40  constructed in accordance with a second alternative embodiment. The panel includes a polygon-shaped main panel body  42  similar to the embodiment illustrated in FIG.  2 . As illustrated, the panel  40  of this embodiment further includes a secondary layer  44  having a polygon-shaped body having a top surface  44   a  and an bottom surface  44   b . The thickness of the secondary layer  44  may be equal to the thickness of the main panel body  42 . The secondary layer  44  is adapted to form a seal  48  with the main panel body  42  to form a cavity  46  between the inner surface  42   b  of the main panel body  42  and the top surface  44   a  of the secondary layer  44 . The cavity may be used for insulation, mounting hardware, utility installation or other ancillary devices. 
     FIG. 2D is a cross-sectional view of a panel  50  constructed in accordance with a third alternative embodiment. The panel has an outer surface  52  which is generally planar. As illustrated, the outer surface  52  and an inner surface  54  are parallel to each other. 
     The present invention can be practiced with panels of various shapes and designs in light of this disclosure. Generally, flat panels are more economical and can be constructed at a lower cost than convex-shaped panels. Flat panels may be produced by converting conventional formed aluminum triangular dome panels to form aluminum kite shape panels. Retooling of existing production methods is required. Convex Kite shaped panels may be formed by thermoforming high-density polyethylene. It will be apparent to others skilled in the art that many other suitable panel creation techniques can be utilized in light of this disclosure. 
     General dome design will now be briefly discussed. A geodesic dome is typically formed from a series of subdivisions or repetitive “basic building blocks.” One measure of the subdivisions of a geodesic dome is the dome&#39;s frequency. A discussion of frequency and methods to subdivide a geodesic dome design can be found in “Synergetics—Explorations in the Geometry of Thinking” by R. Buckminster Fuller, MacMillan Publishing Co., Inc., 866 Third Avenue, New York, N.Y. 1975, which is hereby incorporated in its entirety. 
     Referring now to FIG. 3A, a schematic view of one combination  60  of prior art panels is illustrated. The combination  60  represents a subdivision or “basic building block” of a conventional geodesic dome. As illustrated, the combination  60  includes two different panels types  62 ,  64  and a total of four panels. 
     Referring now to FIG. 3B, a schematic view of one combination  70  of panels constructed in accordance with one embodiment of the present invention is illustrated. The combination  70  covers approximately the same area as the conventional combination  60  illustrated in FIG.  3 A. However, the combination  70  includes only one panel design  72  and only three total panels, one less panel type than the prior art combination  60 . The panels  72  are sealingly joined and may be made to impede moisture by any conventional fastening method including screwing, riveting, gluing, taping and welding. 
     It is well known in the art, larger domes require more different common panel types and generally, more total number of panels. Referring now to FIG. 4A, a schematic view of one combination  80  of prior art panels is illustrated. Six different panel types  82 ,  84 ,  86 ,  87 ,  88 ,  89  and a total of 16 panels are required to form this combination  80 . 
     Referring now to FIG. 4B, a schematic view of one combination  90  of panels constructed in accordance with an alternative embodiment of the present invention is illustrated. The combination  90  covers approximately the same area as the conventional combination  80  illustrated in FIG.  4 A. However, the combination  90  includes only four panel designs  92 ,  94 ,  96 ,  98  and only twelve total panels, two less panel types than the prior art combination  80  and four less total panels. 
     Table 1 that follows illustrates the part count and piece count efficiencies offered by the present invention as compared to prior art triangle-shaped panels. For purposes of example only, the subdivisions required for three dome sizes (A, B and C) are represented. It will be apparent to others skilled in the art that many other suitable subdivisions and dome sizes can be utilized in light of this disclosure. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                  Part Count and Piece Count Efficiency of Present Invention 
               
            
           
           
               
               
               
               
            
               
                   
                 Common 
                 Panels Per 
                 Total Panels 
               
               
                   
                 Panel Types 
                 Subdivision 
                 Per Dome 
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Dome 
                 Triangle 
                 Kite 
                 Triangle 
                 Kite 
                 Triangle 
                 Kite 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
            
               
                 A 
                 2 
                 1 
                 4 
                 3 
                 40 
                 30 
               
               
                 B 
                 6 
                 4 
                 16 
                 12 
                 160 
                 120 
               
               
                 C 
                 9 
                 8 
                 36 
                 27 
                 360 
                 270 
               
               
                   
               
            
           
         
       
     
     The frequency of each dome represented in Table 1 is as follows. Dome A is 2, Dome B is 4, and the frequency for Dome C is 6. As would be expected by others with ordinary skill in the art, the domes increases in size as the number of panels increases. 
     As is shown in Table 1, the present invention offers fewer number of common panel types and fewer total panels for the same size dome. As a result, the present invention yields a simplified bill-of-materials. The production is subsequently more efficient and less costly than conventional dome designs. 
     Referring now to FIG. 5, a plan view of a geodesic dome substantially constructed from a group of standardized kite panels as shown in FIGS. 1,  2 A and  3 B is illustrated. The panels  102  as illustrated have a convex compound curvature such that an integrated assembly of a plurality of the panels substantially forms a geodesic dome structure. As illustrated, a majority of the panels  102  are uniform in shape and size. A repetitive subdivision is formed by three standardized panels  104   a,    104   b,    104   c.  A perspective view of a geodesic dome shown in FIG. 5 is illustrated in FIG.  6 . 
     A method of constructing a geodesic dome structure in accordance with one embodiment of the present invention will now be discussed. The method includes the first step of selecting a plurality of construction panels which include a kite-shaped body having a convex outer surface, an inner surface, four panel edges such that two edges include a lip seam edge suitable for mating with an adjacent panel edge of a corresponding panel and four panel corners defined by the intersection of the four panel edges. Two axes are formed such that each axis leads from a first panel corner to a second panel corner, wherein the second panel corner does not share a common panel edge with the first panel corner. 
     The second method step includes mating a panel edge of a first panel to a panel edge of a second panel, such that a seal is formed, wherein the first panel and the second panel may be uniformly shaped and dimensioned. 
     The next method step includes fastening the seal to impede moisture by a fastening method selected from the group consisting of screwing, riveting, gluing, taping and welding. 
     The next method step includes mating a panel edge of a third panel to a panel edge of the second panel, such that a seal is formed and fastened, wherein the second panel and the third panel may be uniformly shaped and dimensioned. The steps of mating and fastening are repeated such that a geodesic dome structure is substantially formed. 
     In one embodiment, the panel may include a pair of primary edges and a pair of secondary edges, wherein each pair includes a straight seam edge and a lip seam edge, such that a first panel primary straight seam edge suitably mates with a second panel primary lip seam edge, and the first panel secondary straight seam edge suitably mates with a third panel secondary lip seam edge. 
     In one embodiment, the panel may include a kite-shaped quadrilateral, wherein the quadrilateral is symmetric with respect to a primary axis, such that said primary axis intersects a corner defined by the intersection of said pair of primary edges. 
     Although the present invention has been described with a degree of particularity, it is the intent of the Applicant that the invention include all modifications and alterations apparent to those skilled in the art from the above detailed description and within the spirit or scope of the appended claims.