DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Turning to the drawings, FIGS. 1A, 1B, and 2 show a preferred embodiment of a composite panel 10, in accordance with the present invention. Generally, the panel 10 includes a first or outer skin 12 defining an upper edge 14, a lower edge 16, and side edges 18. In addition, the panel 10 includes a second or inner skin 22 also defining an upper edge 24, a lower edge 26, and side edges 28. The first and second skins 12, 22 are spaced apart a predetermined distance, for example, by one or more connectors 32 and/or one or more internal I-beam supports 40, thereby defining a cavity 30 therebetween. The cavity 30 may be filled with an insulating material, e.g., a foam, such as polyisocyanurate, as described further below.

[0032] A connector 32 may be provided along one set of side edges 18, 28, and preferably on both opposing side edges 18, 28. Each connector 32 generally includes a tongue 34 and a complementary shaped groove 36 extending along a length of the connector 32. Preferably, the tongue 34 and groove 36 are disposed adjacent one another to generally define an “L” shape. The tongue 34 and groove 36 define an inside face 37 between them having a slot 38 therein. Preferably, the inside face 37 extends substantially parallel to a plane defined by the first and second skins 12, 22 of the connector 18 to facilitate interlocking connectors on adjacent panels, e.g., in a generally planar orientation, as explained further below. The slot 38 preferably has a generally hemispherical cross-section, although other alternative cross-sections may also be provided, such as square, rectangular or other radially symmetrical shapes. Further, the slot 38 may be provided at a midpoint of the inside face 37, or in some other symmetrical manner.

[0033] As shown in FIGS. 5A-5D, the connector 32 may be configured to slidably interlock with a similar connector 32′ provided on another panel 10′ or a connector element 132, 232, 332 for special connectors 110, 210, 310, as described further below. For example, as best seen in FIG. 5A, when connectors 32, 32′ are interlocked, the tongues 34, 34′ may be received in the mating grooves 36′, 36. As this occurs, the slots 38, 38′ become aligned with one another to together define a passage 39. The passage 39 may extend generally parallel to side edges of the panels 10, 10′, e.g., between their upper and lower edges. Alternatively, other connectors, such as “H” strips or other tongue and groove connectors (not shown), may be used instead of the generally “L” shaped connectors 32.

[0034] Returning to FIGS. 1A, 1B, and 2, the panel 10 may include one or more internal support members, such as I-beams 40, between the first and second skins 12, 22. Each I-beam 40 may have a cross-section including opposing webs 42, 44 spaced apart by a leg 46, preferably such that the I-beam 40 has a height similar to the spacing between the first and second skins 12, 22. In addition, the I-beam(s) 40 may include a tubular segment 48 formed in the leg 46, e.g., defining a utility chase. Alternatively or in addition, the panel 10 may include one or more tubular elements 52 (shown in FIG. 1B) within the cavity 30 separate from the I-beam(s) 40 for providing utility chases.

[0035] Each I-beam 40 may have a length similar to or slightly less than a height of the first and second skins 12, 22. Preferably, each I-beam 40 extends substantially parallel to the side edges 18, 28, e.g., from the lower edges 16, 26 towards the upper edges 14, 24 of the first and second skins 12, 22. Thus, the I-beam(s) 40 may divide the cavity 30 into subcavities 30a-30c (shown in FIG. 1B), each of which may be filled with an insulating material.

[0036] Optionally, the upper edges 18, 28 and/or lower edges 16, 26 may be sealed or otherwise faced off, e.g., to substantially seal the cavity 30. For example, as shown in FIGS. 2 and 3, a top plate 60 may be provided between the upper edges 18, 28 of the first and second skins 12, 22 to face off . Preferably, the top plate 60 includes opposing legs 64 connected by a base 66, thereby defining a “U” shaped channel 62. Preferably, the top plate 60 is disposed such that the channel 62 is disposed away from the lower edges 16, 26 and more preferably such that the legs 64 of the top plate 60 are substantially flush with the upper edges 18, 28 of the skins 12, 22, as best seen in FIG. 3.

[0037] Returning to FIG. 2, the first skin 12 may be formed from plastic or composite material. “Composite” material as used herein generally refers to material that is formed from fiber materials impregnated in a resin. The term “fiber-reinforced plastic” or “FRP” may be used interchangeably herein with the term “composite” to refer to the same class of materials. Generally, the fiber material may be formed from long fiber strands, e.g., woven cloth mat or other configurations of filaments, made from generally inert materials, such as glass, carbon, graphite, boron, quartz and the like.

[0038] The resin may be selected from a number of thermoset plastics, such as polyvinyl chloride (PVC) or PVC derivatives, and/or thermoplastic materials, such as phenolics, polyesters, vinylesters, polypropylenes, epoxies, and polycarbonates. Ultraviolet inhibitors may be added, if desired, to all or selected components, such as exterior skins, to protect the components from damage due to exposure to sunlight. Phenolic resins may be preferred as they have a higher resistance to fire as compared to other resins, i.e., they have relatively low coefficients of flame spread and smoke generation during combustion, and may be formulated such that they will not support substantial combustion at all. Phenolic resins also do not include styrenes, which may provide an improved environment during manufacturing and/or pre-assembly of the panels over other resins. Phenolic resins, however, may be corrosive and consequently may require special protection of manufacturing equipment and/or panel components during manufacturing. In a preferred form of the present invention, fiberglass is impregnated within a phenolic resin in proportions of about 15-60% fiberglass by volume, and more preferably about 25-35% fiberglass, to provide a preferred composite material.

[0039] The second skin 22 may be formed from a variety of materials, such as plastic or composite material, similar to the first skin 12. Preferably, however, the second skin 22 includes a panel of drywall material, e.g., paper-covered gypsum board, such that the second skin 22 may provide a rough finish for an interior surface of a structure (not shown), as explained further below.

[0040] The connector(s) 32 may be formed from plastic or composite material, similar to the first and second skins 12, 22. Because the connector(s) 32 may not be exposed upon assembly of a building structure using the panel 10, the connector(s) 32 may be formed from plastic, such as polyvinyl chloride (PVC), which may be extruded or otherwise formed relatively easily and inexpensively, as compared to composite materials. Similarly, the I-beam(s) 40 and/or top plate 60 may be formed from plastic or composite material, and preferably from plastic, such as PVC. Alternatively, if additional fire resistance is desired, the connector(s) 32, I-beam(s) 40, and/or top plate 60 may be formed from phenolic resin FRP.

[0041] To manufacture a panel in accordance with the present invention, the first skin 12 may initially be manufactured from composite material, e.g., including filaments made from generally inert materials impregnated in a thermoset plastic resin or a thermoplastic resin, as described above. The first skin 12 (and the second skin 22, if formed from composite material) may be formed by a pultrusion process during which fiber material is directed through a resin bath. The resulting composite is pulled through a die where it is formed into a desired shape, and cured. Similarly, composite accessories, e.g., connectors and/or I-beams, may also be formed using a pultrusion process. Such a process may allow the components to be manufactured on a continuous basis using a panel machine or impregnator, known to those skilled in the art. The composite material may be fed continuously through the die, and then cut into predetermined lengths once cured. Because of the partial automation provided by pultrusion processes, high volume, high efficiency manufacturing may be obtained.

[0042] Alternatively, “open mold” wet lay-up methods may be used during which one or more of the components may be manufactured individually. This may reduce output volume, but may allow special textures, such as an architectural finish, e.g., a stone or brick pattern, a stucco pattern, a tile pattern, a wooden panel pattern, and the like, to be incorporated into finished components, such as an outer skin. For example, sheet molding compound or “pre-preg” may be used, in which resin is pre-applied to the fiber reinforcement and provided in an uncured sheet form. The sheet may be placed in a mold having a surface finish thereon, and heat and/or pressure may be applied to cure the material and mold the surface finish directly into the sheet.

[0043] No matter what method is used, the first skin(s) 12 (and optionally second skin 22) may be formed into any desired size, i.e., height and width, and or cut into desired sizes from production-size skins. Preferably, the skin(s) 12 may be formed into standard widths, e.g., seventy two inches (72 in.), that provide desired structural characteristics and/or handling weights for the resulting panels.

[0044] The first skin 12 may be positioned in a jig (not shown) with an inside surface facing upwardly, and then any desired accessories may be bonded to the inside surface of the first skin 12, e.g., using an adhesive, such as a two part polyurethane or epoxy adhesive. For example, connectors 32 may be aligned such that they overlap the side edges 18, i.e., providing a lapped joint, and bonded to the first skin 12. Similarly, any internal I-beams 40 may be positioned substantially parallel to the side edges 18, e.g., distributed evenly between the side edges 18 and bonded to the inside surface of the first skin 12. In a preferred embodiment, the connectors 32 and I-beams 40 are each bonded such that one end is substantially flush with the lower edge 16 and the other end is below the upper edge 14, as may be seen in FIG. 1A. Top plate 60 may also be positioned along the upper edge 18 and bonded to the inside of the first skin 12. Preferably, the top plate 60 is positioned adjacent the ends of the connectors 32 and/or I-beams 40 such that the top plate 60 is substantially flush with the upper edge 18.

[0045] The second skin 22 may then be overlaid and bonded to the connectors 32, I-beams 40, and/or top plate 60. The second skin 22 preferably has dimensions similar to the first skin 12, such that the skins 12, 22 may be aligned with one other to provide a substantially squared panel 10. In a preferred embodiment, the second skin 22 is a provided from a drywall material, although the second skin 22 may also be composite. For drywall material, an adhesive, such as a two part polyurethane adhesive or epoxy adhesive, may be used to bond the drywall material directly to the connectors 32 and/or I-beams 40. Alternatively, an intermediate layer of plastic or composite (not shown) may be overlaid and bonded to the connectors 32 and/or I-beams 40, and the skin of drywall material may be bonded to the intermediate layer. It will be appreciated that the order of the steps described above is not important, and that the panel 10 may be assembled using any sequence of steps that result in the assembled configuration of the panel 10 shown in FIGS. 1A and 1B.

[0046] With the skins 12, 22 bonded to the connectors 32, a cavity 30 is defined that may be filled with an insulating material, for example, to provide increased insulation values, security, sound absorption, fire resistance and/or structural strength. Preferably, insulation material may be a foam that is injected or otherwise introduced into the interior panel spaces after assembly, for example, foam polyurethane, such as polyisocyanurate. Foam material may be preferred, because it may expand after introduction into the cavity 30, thereby minimizing the risk of creating voids within the panel 10. Alternatively, other flowable materials may be used to fill the cavity 30, such as light-weight concrete. If the cavity 30 is divided into subcavities, e.g., by internal supports, each subcavity may be independently filled with foam or other insulation, or the internal supports may include holes to accommodate the insulation flowing between the subcavities. In a further alternative, the cavity 30 may remain empty, and recycled filler materials and/or naturally-occurring filler materials available at or near the erection site may be used to fill the cavity immediately before erection. In yet a further alternative, insulation, such as conventional fiberglass blanket insulation, may be placed between the connectors 32 and/or I-beams 40 before overlying the second skin 22.

[0047] Other accessories for the panel system, such as the special connectors, channels, and/or trim, may also be manufactured, for example, using a pultrusion method or using an extrusion process, as described above. Although an extrusion process may be performed on phenolic resin composites, PVC or PVC derivative materials may be extruded more easily, and may be preferred for accessory components that are not likely to be exposed upon erection of the structure. For exposed accessories, such as the comer connector 132, spacer connector 232, and “T” connector 332 described below, a phenolic resin composite is preferred, and the accessories may be manufactured using a pultrusion or extrusion process.

[0048] For example, as shown in FIG. 5B, a comer connector 132 may be provided for connecting panels 10, 10′ in a transverse orientation, e.g., ninety degrees from one another. The comer connector 132 may include an elongate generally square shaped column portion 134 from which a pair of panel connectors 136, 136′ extend. Preferably, the panel connectors 136, 136′ are integrally molded to the column portion 134, e.g., from a phenolic resin. Preferably, the panel connectors 136, 136′ are oriented substantially perpendicularly to one another to generally define an “L” shape. The panel connectors 136, 136′ generally include tongues 138 and grooves 140 adjacent to one another, thereby defining an inside surface 142 having a generally hemispherical slot 144 therein, similar to the connectors 32 described above.

[0049] Turning to FIG. 5C, a spacer connector 232 is shown that may be used to connect two panels 10, 10′ in a substantially planar configuration. Similar to the corner connector 132, the space connector 232 includes a pair of panel connectors 236, 236.′ The panel connectors 236, 236′ include tongues 238 and grooves 240 adjacent to one another, thereby defining an inside surface 242 having a generally hemispherical slot 244 therein, similar to the comer connector 132. Preferably, the panel connectors 236, 236′ are oriented away from one another and spaced apart a predetermined distance. Thus, the spacer connector 232 may be used to connect adjacent panels 10, 10′ when the distance between the panels 10, 10′ is smaller than practicable to manufacture a relatively narrow panel.

[0050] Turning to FIG. 5D, a generally “T” shaped connector 332 is shown that includes three panel connectors 336, 336′, 336. “Preferably, each of the panel connectors 336, 336′, 336” include tongues 338 and grooves 340 adjacent to one another, thereby defining an inside surface 242 having a generally hemispherical slot 244 therein, similar to the connectors 32, 132 described above. A “T” shaped connector may facilitate connection between outer wall panels 10, 10′ of a building structure and an interior wall panel 10″ abutting against the outer wall panels 10, 10.′ Alternatively, a “U” channel (not shown) may be used to secure intersecting walls, for example, where an interior wall may be connected to an exterior wall of a structure.

[0051] Turning to FIG. 6, a set of panels and accessories may be manufactured, e.g., using the methods described above, to provide a system for erecting a building structure. The set of panels may include a plurality of standard panels and/or one or more custom panels such that, when they are properly assembled, the building structure may be erected. For example, a set of standard width wall panels 410, 412, 414 may be provided, as shown, if the configuration of the structure allows. Alternatively, custom width panels (not shown) and/or spacer connectors 232 (not shown in FIG. 6) may be used to complete dimensions that do not accommodate use of standard width panels. Architectural features, such as window or door openings (not shown), may be cut into individual panels during manufacturing, or may be field cut during erection.

[0052] Optionally, composite panels may be manufactured for use as internal walls, such as the representative panel 416 shown. Alternatively, internal walls may be provided from conventional materials. Similarly, composite panels may be provided for a roof of the structure, such as the representative panels 418. Alternatively, a roof may be fabricated from conventional materials that may be connected to composite wall panels, as explained further below.

[0053] The composite panels are preferably manufactured and assembled at a manufacturing site where efficiencies may be realized and/or labor costs controlled more effectively. Thus, upon delivery to an erection site, no assembling individual panels may be required. Alternatively, if shipping volume is an important consideration, the panel components may be shipped unassembled, and assembled and bonded into panels at or near the erection site.

[0054] With reference to FIGS. 3, 4, and 6, a method for erecting a building structure, such as the structure 400 shown in FIG. 6, using a plurality of panels in accordance with the present invention, is now described. Initially, a foundation may be created in a conventional manner, e.g., a raised foundation and/or a concrete slab, such as the foundation 90 shown in FIG. 4. Base channel 70 may be secured to the foundation 90, for example, anchored using fasteners 72, such as bolts or screws, and/or using adhesives. Preferably, the base channel 70 is a “U” shaped channel including a pair of opposing legs 74 connected by a base 76, thereby defining a channel 78 having a size to fit panels therein. The base channel 70 may be pultruded or extruded from plastic or composite material, as described above. Preferably, the base channel 70 is extruded from PVC, as it may not be exposed once the building structure is complete. The base channel 70 may be cut to length and laid out to define a footprint (shown partially in FIG. 6) of the structure before installing the panels or as wall segments are assembled.

[0055] As shown in FIG. 4, a lower edge of a first panel 10 may be placed into the base channel 70 in a substantially vertical orientation. Optionally, the first panel 10 may be secured to the base channel 70, for example, by drilling or screwing fasteners, e.g., screws or rivets, through the legs 74 into the first and/or second skins 12, 22. The fasteners may be spaced apart along the base channel 70 a predetermined distance to ensure structural engagement between the panel 10 and the base channel 70.

[0056] A lower edge of a second panel (not shown) may be placed into the base channel 70 adjacent the first panel member 10 and then slid towards the first panel 10. As shown in FIG. 5A, connectors 32, 32′(also not shown) on the first panel 10 and the second panel 10′ may interlock such that the first and second panels 10, 10′ are disposed in a substantially planar configuration. Preferably, once the connectors 32, 32′ are fully interlocked, the slots 38, 38′ together define an passage 39. A pin, such as an elongate rod or tube (not shown), e.g., formed from metal, wood, or composite material, may be inserted into the passage 39. The pin may substantially lock the connectors 32, 32′ together, and consequently secure the panels 10, 10′ together. The second panel may be secured to the base channel 70, for example, using fasteners, similar to the first panel 10. It will be appreciated that the fasteners may be used to secure the panels to the base channel before or after inserting any pins to secure the panels to one another.

[0057] Generally, with particular reference to FIG. 6, erection may begin in a comer of the structure, for example, at the comer labeled “A.” Initially, a comer connector 132 may be placed into one end of a base channel 70, and adjacent panels 412, 414, etc. may be successively interlocked with the comer connector 132 and with one another. Any spacer connectors or “T” connectors (not shown) may be interlocked as appropriate until the next comer connector 132 is installed. Each of the walls may be erected in a similar manner, as will be appreciated by those skilled in the art. Pins (not shown) may be used to secured the panels and/or connectors to one another, and fasteners (not shown) may be used to secure the panels and/or connectors to the base channel 70. If desired, trim (not shown) may be applied along the panels to cover the base channel 70 and/or any fasteners, which may be formed from conventional materials, plastic, or composite materials.

[0058] Turning to FIG. 3, any or all of the wall panels described above, represented by panel 10, may include a top channel 60 bonded between the first and second skins 12, 22. A top plate 82 may be inserted and/or mounted into the channel 62 defined by the top channel 60, e.g., along a between a plurality of adjacent panels (not shown). The top plate 82 may be an interface for connecting a roof structure to the wall panels, and may be formed from conventional materials, e.g., lumber or steel, or from plastic or composite materials. Preferably, the top plate 82 is a conventional structural element, such as a piece of lumber (e.g., a 2″×4″), that is secured into the channel 62 using fasteners 80, such as nails, screws, bolts, and the like. The top plate 82 may include a metal sheet 84 secured along the top plate 82 to which trusses or other roof structure components (not shown) may be secured.

[0059] A roof structure (not shown) may be secured to the trusses that may be provided from conventional materials. Alternatively, as shown in FIG. 6, a roof including composite panels 418 may be secured to the top of the wall panels 412, 414. Exemplary connectors for securing composite roof panels to composite wall panels are disclosed in the parent applications incorporated above.

[0060] Turning to FIG. 7, any of the wall panels, such as the representative panel 10, may include internal support members, such as I-beams 40 including tubular segments 48 providing utility chases. Alternatively, separate tubular chases (not shown) may be provided within the panels. Preferably, the chases 48 are disposed vertically within the panel 10, thereby providing a simplified method for installing utility accessories, such as electrical boxes 86. When a location of an electrical box 86 is identified, an electrical cable or wire 88 may be directed into the nearest I-beam tubular segment 48 of panel 10. This may require cutting an opening in the top channel 60 of the panel 10. An opening may be created, e.g., in an inner skin 12 of the panel 10 to access the tubular segment 48, and pull the wire 88 from within the chase.

[0061] The electrical box 86 may be secured to the to the inner skin 12 of the panel 10, and an outlet, switch, and the like (not shown) may be coupled to the wire 88 and mounted to the electrical box 86. If the inner skin 12 is provided from composite material, the electrical box may also be provided from plastic or composite material and bonded to the inner skin 12. Alternatively, the electrical box 86 may be secured to the inner skin 12 using fasteners, such as screws, nails, and the like. Although attic access is shown for introducing wires 86 into the chases 48, a crawl space, if the structure includes a raised foundation (not shown), may be used to access the chases 48 from below. Similarly, other utilities, such as plumbing and heating accessories, may be introduced into walls using such chases, in addition to or instead of electrical utilities, although the size of the chase required may vary depending upon the accessory being introduced.

[0062] A significant advantage of composite panels, as compared to wood or other traditional materials, is that the composition of composite materials may be modified in a predetermined manner to optimize the structural characteristics of components or systems formed using them. For example, the fiber reinforcement content of the material may be increased to generally increase the strength of the resulting structure, particular arrangements of fibers may be selected to provide selected structural properties, and the like. In addition, the spacing and construction of internal support members may be selected to provide desired structural properties.

[0063] In addition, an exterior skin of composite material may be manufactured with a desired architectural finish, thereby reducing exterior finish work on the exterior of the structure. Similarly, composite panels including drywall inner skins may provide a rough finish for the interior of the structure, only requiring painting or other finishes.

[0064] Another advantage of connection systems in accordance with the present invention is that special tools and fasteners may be eliminated. Although fasteners may be required to secure the wall panels to base channel or to connect a roof structure to wall panels, the connectors of the present system may only require a single pin to assemble and secure adjacent wall panels. Thus, a substantial volume of hardware generally required for erecting building structures may be eliminated.

[0065] While the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the appended claims.