This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/917,454, filed May 11, 2007, the entire disclosure of which is incorporated by reference herein.
This application is also related to U.S. Pat. Nos. 6,701,683, 6,729,090 and 6,898,908 and 7,100,336, the entire disclosures of which are incorporated by reference herein.
This application is also related to pending U.S. patent application Ser. Nos. 11/121,267, 11/096,705, 11/122,792 and 11/456,057, the entire disclosures of which are incorporated by reference herein.
FIELD OF THE INVENTION The present invention is generally related to low density concrete wall panels that employ insulation members that are internally reinforced.
BACKGROUND OF THE INVENTION Due to the high cost of traditional concrete components and the expensive transportation and labor costs associated therewith, there is a significant need in the construction industry to provide lightweight, precast, composite building panels that have superior strength and insulative properties. Previous attempts to provide these types of building panels have failed due to the expensive transportation costs and less than ideal insulative and thermal conductivity properties associated with prefabricated concrete wire-reinforced products. Further, due to the brittle nature of concrete, many of the previously used building panels are prone to cracks and other damage during transportation.
Concrete wall panels are often expansive. The large weight per square foot ratio of prior art building panels has resulted in significant expenses arising not only from the amount of materials needed for fabrication, but also the cost of transporting and erecting the wall panels. Panel weight also places effective limits on the height of structures, such as stacked modules e.g., due to load limitations of the building foundations, footings and/or lowermost modules. Furthermore, substantial fabrication expenses often arise from design, material, and labor costs associated with providing and placing reinforcement materials within a building panel. Accordingly, it would be useful to provide a wall panel system for modular construction that is relatively light, can be readily stacked to increased heights and, preferably, inexpensive to design, manufacture, transport and erect.
Furthermore, in many situations prefabricated concrete panels or modules are situated in locations where it is desirable to have openings therethrough to accommodate doorways, windows, cables, pipes and the like. In some previous approaches, panels were required to be specially designed and cast so as to include any necessary openings. This step requires careful planning and design, thus increasing the inherent costs due to the special, non-standard configuration of such panels. In other approaches, panels were cast without such openings and the openings were formed after casting, e.g. by sawing or similar procedures. Such post-casting procedures are relatively labor-intensive and expensive. In many processes for creating openings, there is a relatively high potential for cracking or splitting of the panel or module. Accordingly, it would be useful to provide panels and modules wherein openings such as doors and windows may be integrated in desired locations with a reduced potential for cracking or splitting, and which is cost effective during the manufacturing process.
One prior art example of a composite building panel that attempts to resolve the aforementioned problems inherent in modular panel construction of the prior art is described in U.S. Pat. No. 6,202,375 to Kleinschmidt (“Kleinschmidt”), which is incorporated by reference in its entirety herein. Kleinschmidt provides a building system that utilizes an insulative core bounded by interior and exterior layers of concrete that are held together with a metallic wire mesh positioned on both sides of the insulative core. The wire mesh is embedded in concrete, and held together by a plurality of metallic wires extending through the insulative core at a right angle to the longitudinal plane of the insulative core and concrete panels. Although providing an advantage over homogenous concrete panels, the composite panel disclosed by Kleinschmidt does not provide the necessary strength and stiffness required during transportation and in high wind environments. Further, the metallic wire mesh materials are susceptible to corrosion when exposed to water during fabrication, and have poor insulative qualities due to the high heat transfer properties of metallic wire. Thus the Kleinschmidt panels are more susceptible to failure when exposed to stresses during transportation, assembly or subsequent use.
Further, previously known prefabricated building panels that employ only concrete, insulative foam materials and wire mesh have also not been found to have sufficient tensile and compressive strength. In addition, the insulating members used in the prior art are often fragile and are thus prone to damage during transportation and integration into the concrete wall. More specifically, insulating members are often fabricated of molten polystyrene that is either introduced into a mold to form expanded polystyrene (EPS) foam or extruded to form extruded polystyrene (XPS) foam that is then cut to the required size. EPS is the insulative foam most often found in low-density concrete wall panels, is very brittle and apt to break and is not designed to resist bending, torsional, tension, or compressive loading. EPS is often damaged during handling, which may not be evident until concrete is introduced to a wall form containing the insulation members. For example, the introduction of heavy, wet concrete will load the already placed insulation members, thereby possibly causing a blow-out wherein concrete will infiltrate into a void provided by the insulating members, which will be more apparent upon review of the following. Weakened insulation members may also compromise the structural integrity of the finished concrete wall panel. It is thus desirable to provide a concrete wall panel within insulation members that are stronger and more durable and are more apt to support the weight of concrete during formation.
Thus, it is a long felt need in the field of concrete wall panel construction to provide an insulated concrete wall floor or structural (hereinafter “wall panel”) panel that includes insulation members that are strong and resistant to damage. The following disclosure describes an improved insulation member for use in low-density concrete wall panels that is reinforced such that it resists damage due to handling, is capable of supporting the weight of concrete during fabrication, and enhances the strength of the finished wall panel.
SUMMARY OF THE INVENTION It is one aspect of the present invention to provide an insulating member for incorporation into a preformed low-density concrete panel that forms a void in the finished wall. More specifically, one embodiment of the present invention employs a plurality of cavity forming insulation panels that provide a cavity within the finished wall panel. Thus a lighter wall panel is formed that is easier to transport due to its decreased weight. The cavities in the wall panel also provide locations for the incorporation of conduit for utilities such as electrical, fluid, air, etc. The dead air within the cavities and the insulative properties of the insulation members increase the insulation value of the wall to a level greater than that of a wall made entirely of concrete. For example, one embodiment of the present invention possesses an R value of about 5, which is upgradable to 19 by the addition of insulation into the cavity. The dead air with the cavities also attenuates noise.
It is a related aspect of the present invention to provide a reinforced insulation member. More specifically, embodiments of the present invention employ a reinforced insulated cavity former. That is, instead of using large EPS blocks that are often formed in 8′×8′×30′ sections and cutting them into sheets of 4′×8′×2″ for use in the wall panel, EPS in one embodiment, is molded with a reinforcing textile mesh made preferably of fiberglass that is preferably coated with polyvinyl chloride (PVC). The use of PVC coating is advantageous since it reacts with the molten EPS during formation to create an enhanced bond between the reinforcing mesh and the EPS insulation. The reinforcing mesh may be in the form of strips or sheet, which will be apparent upon review of the detailed description below. In operation, reinforcing mesh is placed in the mold at a predetermined location to yield an insulation member that improves the strength and rigidity and provides exerted by the concrete during formation. Another significant benefit is the reduced size of insulative foam required to achieve the same strength as larger foam panels, thus significantly decreasing cost.
As briefly mentioned above, one embodiment of the present invention possesses enhanced bonding characteristics between the PVC coated reinforcing mesh or “scrim” and the EPS foam. That is, the PVC coating and raw polystyrene have approximately the same melting point. Thus, during molding, the molten EPS will tend to melt the PVC coating, thereby facilitating a chemical bond between the polystyrene and the PVC. It is important to note, that the heat from the EPS does not destroy the PVC bonds (often known as “beads”) that interconnect the individual fiber strands that make up the reinforcing mesh. More specifically, often the mesh reinforcement is created not by weaving, but by placing glass fibers in one direction onto glass fiber oriented in another direction and by dipping this fiber grid into a hot liquid PVC bath. The beads that are present at firm crossings hold the individual fibers together.
As briefly mentioned above, one advantage of employing reinforced insulated members is a decrease in cost. More specifically, costs related to handling, shipping, cutting and waste disposal of large foam blocks is often an obstacle of the construction of insulated concrete wall panels. Embodiments of the present invention reduce the amount of insulated foam by ten times the amount normally used. That is, due to their increased strength, an insulating member with a decreased cross-sectional area may be employed, which reduces the amount of insulation needed. Due to the shape of the insulated cavity formers, a number of cavity forms that can be place in shipping containers is also increased which reduces shipping costs. In addition, since the cavity formers are reinforced, less damage occurs during handling. Finally, the enhanced strength of the insulation panels increase the aggregate strength of the wall panel, which should be apparent to one skilled in the art. Other advantages of the invention will also be apparent to one skilled in the art upon review of the following disclosure.
Thus it is one aspect of the present invention to provide a low density manufactured concrete wall panel, comprising: a low density foam core comprising an upper end, a lower end and lateral edges positioned therebetween and having an exterior surface and an interior surface to define a predetermined depth; a first and a second lateral wall extending downwardly from said lateral edges and extending substantially between said lower end and said upper end to define a substantially hollow portion positioned within the confines of the first wall and the second wall core; and a mesh material positioned within the lower density foam material to provide enhanced strength to the low density core.
It is also an aspect of the present invention to provide a method of manufacturing a low density wall panel with a reinforced foam material having a predetermined shape, comprising: providing a mold with a predetermined shape; positioning a reinforcing material at a predetermined location within said mold; injecting a foam material into the mold; and heating the foam material, wherein said mesh material and said foam bond.
The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these embodiments.
FIG. 1 is a top perspective view of an insulating cavity former shown in FIG. 1;
FIG. 2 is a bottom perspective view of the insulating cavity former shown in FIG. 1;
FIG. 3 is a top perspective of an insulating cavity former that employs a plurality of homogeneous spacers;
FIG. 4 is a bottom perspective of the insulating cavity former shown in FIG. 3;
FIG. 5 is a front elevation view of a mold used to form insulating cavity formers of one embodiment of the present invention;
FIG. 6 is a front elevation view of the FIG. 5;
FIG. 7 is a front elevation view of a form used to fabricate a low density wall panel of one embodiment of the present invention;
FIG. 8 is a front elevation view of the mold shown in FIG. 7 with a plurality of cavity formers positioned therein;
FIG. 9 is a front elevation view of a complete concrete wall panel positioned within the mold;
FIG. 10 is a front elevation view of a plurality of insulating cavity formers stacked in a nesting configuration for transport;
FIG. 11 is a perspective view of a cart with a plurality of insulating cavity formers positioned over a concrete form;
FIG. 12 is a perspective view of a single insulating cavity former of another embodiment of the present invention;
FIG. 13 is a bottom perspective view of the insulating cavity former shown in FIG. 12;
FIG. 14 is a front elevation view of the insulating cavity former as shown in FIG. 12;
FIG. 15 is a front elevation view of the insulating cavity former shown in FIG. 12;
FIG. 16 is a right elevation view of a mold used to fabricate the insulating cavity former shown in FIG. 12;
FIG. 17 is a right elevation view of a mold shown in FIG. 16;
FIG. 18 is a front elevation view of a form used to fabricate a low density wall panel;
FIG. 19 is a front elevation view of a concrete mold having a plurality of insulative cavity formers positioned therein;
FIG. 20 is a front elevation view of a complete concrete wall panel;
FIG. 21 is a front elevation view of a plurality of nested cavity formers;
FIG. 22 is a perspective view of a cart positioned over a form for dispensing a plurality of cavity formers;
FIG. 23 is a right elevation view of an insulated cavity former of another embodiment of the present invention;
FIG. 24 is a detailed view of FIG. 23;
FIG. 25 is a top plan view of the insulating cavity former shown in FIG. 23;
FIG. 26 is a bottom plan view of the insulating cavity former shown in FIG. 23;
FIG. 27 is a perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 28 is a bottom perspective view of the insulating cavity former shown in FIG. 27;
FIG. 29 is a detailed view of the insulating cavity former shown in FIG. 27;
FIG. 30 is a left elevation view of the insulating cavity former shown in FIG. 27;
FIG. 31 is a left elevation view of a plurality of engaged insulating cavity formers;
FIG. 32 is a top perspective view of a plurality of engaged insulating cavity formers; and
FIG. 33 is a bottom perspective view of a plurality of engaged insulating cavity formers;
FIG. 34 is a top perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 35 is a top plan view of the insulating cavity former shown in FIG. 34;
FIG. 36 is a cross-sectional left elevation view of the embodiment shown in FIG. 34;
FIG. 37 is a front elevation view of the embodiment shown in FIG. 34;
FIG. 38 is a detailed view of FIG. 37;
FIG. 39 is a detailed view of FIG. 37;
FIG. 40 is a top perspective view of a plurality of engaged insulating cavity formers; and
FIG. 41 is a left elevation view of the plurality of engaged cavity formers shown in FIG. 40;
FIG. 42 is a top perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 43 is a top plan view of the insulating cavity former shown in FIG. 42;
FIG. 44 is a front elevation view of the insulating cavity former shown in FIG. 42;
FIG. 45 is a detail view of FIG. 44;
FIG. 46 is a front elevation view of the insulating cavity former shown in FIG. 42;
FIG. 47 is a detail view of FIG. 46;
FIG. 47A is a detail view of an alternate embodiment of FIG. 46;
FIG. 47B is a partial top plan view of FIG. 47A;
FIG. 48 is a detail view of FIG. 46;
FIG. 49 is a cross sectional view of FIG. 46;
FIG. 50 is a top perspective view of a plurality of engaged insulating cavity formers;
FIG. 51 is a left elevation view of the plurality of engaged insulating cavity formers shown in FIG. 50;
FIG. 52 is a top perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 53 is a top plan view of the insulating cavity former shown in FIG. 52;
FIG. 54 is a front elevation view of the insulating cavity former shown in FIG. 52;
FIG. 55 is a detailed view of FIG. 54;
FIG. 56 is a front elevation view of the insulating cavity former shown in FIG. 52;
FIG. 57 is a detailed view of FIG. 56;
FIG. 58 is a detailed view of FIG. 56;
FIG. 59 is a cross sectional view of FIG. 54;
FIG. 60 is a top perspective view of a plurality of engaged insulating cavity formers;
FIG. 61 is a left elevation view of the plurality of insulating cavity formers shown in FIG. 60;
FIG. 62 is a perspective view of a shear nail employed by embodiments of the present invention;
FIG. 63 is a top perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 64 is a top plan view of the insulating cavity former shown in FIG. 63;
FIG. 65 is a front elevation view of the insulating cavity former shown in FIG. 63;
FIG. 66 is a detail view of FIG. 65;
FIG. 67 is a front elevation view of the insulating cavity former shown in FIG. 63;
FIG. 68 is a detail view of FIG. 67;
FIG. 69 is a detail view of FIG. 67;
FIG. 70 is a cross-sectional view of FIG. 65;
FIG. 71 is a top perspective view of a plurality of engaged insulating cavity formers;
FIG. 72 is a left elevation view of the plurality of engaged insulating cavity formers shown in FIG. 71;
FIG. 73 is a top perspective view of an insulating cavity former of another embodiment of the present invention;
FIG. 74 is a top plan view of the insulating cavity former shown in FIG. 73;
FIG. 75 is a front elevation view of the insulating cavity former shown in FIG. 73;
FIG. 76 is a detailed view of FIG. 75;
FIG. 77 is a front elevation view of the insulating cavity former shown in FIG. 73;
FIG. 78 is a detailed view of FIG. 77;
FIG. 79 is a detailed view of FIG. 77;
FIG. 80 is a cross sectional view of FIG. 75;
FIG. 81 is a top perspective view of a plurality of engaged insulating cavity formers;
FIG. 82 is a left elevation view of the plurality of insulating cavity formers shown in FIG. 81; and
FIG. 83 is a perspective view of a tapered pin employed by embodiments of the present invention;
To assist in the understanding of the present invention the following list of components and associated numbering found in the drawings is provided herein:
# Component
2 Wall panel
6 Cavity former
10 Cavity
14 Insulation
18 Reinforcing mesh
22 Mold
26 Planar surface
30 Leg
34 Spacer
38 Rib
42 Aperture
50 Roll
54 Upper mold
58 Lower mold
62 Stud
66 Form
70 Side form
74 Inner wall
78 Protrusion
82 Concrete
86 Reinforcement
90 Cart
94 Ramp
98 Void
102 Upper surface
106 Lower surface
110 End wall
114 Lip
118 Seat
122 Port
126 Recess
130 Groove
134 Gusset
138 Clip
142 Rebar bridge
146 Upper surface
148 Groove
150 Channel
152 Fibrous concrete
156 Slot
160 Shear nail
164 Arm
168 Locator
172 Pin
179 Film
It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION Referring now to FIGS. 1-83, a low density wall panel 2 that generally employs a plurality of insulating cavity formers 6 (hereinafter “cavity former”) is shown. Although the term “wall panel” is used throughout this specification, one skilled in the art will appreciate that cavity formers 6 as described herein may be incorporated into foundation wall panels, floors, ceilings, and any other building component of a structure. Embodiments of the present invention employ reinforced cavity formers 6 to create cavities 10 within the preformed concrete wall 2. The cavities 10 in combination with the insulation 14 that is used to form the cavity formers, decreases heat transfer through the wall panel 2 and greatly reduces the weight of the wall panel 2 such that the wall panel 2 is cost effective to transport and erect. Preferably, cavity formers 6 include a reinforcing mesh 18 such as fiberglass. During fabrication, fiberglass mesh 18 is coated with polyvinyl chloride (PVC), and is positioned within a mold 22. Thereafter, molten expanded polystyrene (EPS) is added to the mold 22 to form a cavity former 2 of a predetermined shape. In one embodiment, the heat of the molten EPS is approximately the same as the melting point of the PVC coating of the mesh 18. Thus, during fabrication, a tight mechanical and/or chemical bond is formed between the EPS foam and the PVC coated mesh 18, thereby providing a strengthened cavity former.
Referring now to FIGS. 1 and 2, a cavity former 6 of one embodiment of the present invention is provided that is designed to form a plurality of cavities 10 with a finished wall. The cavity former 6 is generally comprised of a planar surface 26 with two legs 30 extending therefrom that define the cavity 10. During fabrication, reinforcement 18 is added to the EPS foam to increase the strength and stiffness of the finished cavity former 6. Although a three piece cavity former 6 is shown herein, one skilled in the art will appreciate that cavity formers 6 may provide a single cavity 10 or a plurality thereof depending on the specific design. The reinforcement 18 may be added to the cavity former 6 via a plurality of strips or a sheet, which will be explained in further detail below. The legs 30 of the cavity former are separated by spacers 34 that allow concrete to be placed between adjacent cavities 10 to form a rib.
Referring now to FIGS. 3 and 4, another embodiment of a cavity former 6 is shown that includes spacers 34 with a plurality of apertures 42 therethrough that provide handles to aid in transportation of the cavity formers 6. The apertures 42 also have an added benefit of decreasing the weight of the cavity former 6 which also facilitates transportation. In addition, the apertures 42 allow concrete to traverse from a point adjacent to the planar surface 26 of the cavity formers 6 to a point under the spacer 34, thereby allowing for the formation of a continuous concrete rib through the thickness of the concrete wall, which will be apparent upon review of the remaining figures.
Referring now to FIGS. 5 and 6, the mold 22 used to create cavity formers in one embodiment of the present invention is provided. In operation, a roll 50 of reinforcing mesh 18, which is preferably coated with PVC, is positioned between an upper mold 54 and a lower mold 58. The roll 50 may be comprised of a sheet of reinforcing mesh 18 that extends the entire width of the mold 22 or a plurality of discreet mesh strips that are positioned at varying locations within the mold 22. One skilled in the art will appreciate that the reinforcing mesh 18 possesses any orientation of fibers, such as random, 0 degrees and 90 degrees, 45 and 45 degrees etc. to provide the desired composite material properties. Further, it is contemplated that more than one sheet of reinforcement may be employed. More specifically, it is envisioned that multiple spaced layers of reinforcement be employed, which may be oriented relative to each other. The lower mold 58 also includes locations for the positioning of studs 62 that are to be integrated into the legs of the cavity formers. The studs 62 are used to help position and secure the cavity formers when they are introduced to concrete.
FIG. 6, which is a right perspective of FIG. 5, illustrates how the reinforcing mesh 18 can be a continuous sheet that is positioned between the upper mold 54 and the lower mold 58. Preferably, the reinforcing mesh is placed under tension during the fabrication process. This figure also distinctly shows how the mold 22 is adapted to form the planar surface at the top of the cavity former and the legs that emanate therefrom. The studs 62 are also succinctly shown positioned in the area that will define the ends of the legs of the cavity former 6.
Referring now to FIGS. 7-9, the fabrication of a wall panel 2 is shown and described herein. In operation, a form 66 is employed that includes side forms 70 extending therefrom. The side form 70 also includes an inner wall 74 that may include a protrusion 78. Initially, a layer of concrete 82 is added to the form. One skilled in the art will appreciate that this initial layer may be designed to comprise an inner surface of a finished wall wherein the material placed is adapted to receive fasteners, such as Sheet-Crete as described in U.S. Patent Application Ser. No. 60/741,487, which is incorporated by reference herein. That is, a layer comprised of a mixture that includes fly ash, PVA fibers, pearlite and blended sands, which is fire resistant, substantially impermeable and that possesses high flexural strength, may be used. Reinforcement 86 such as prestressed strands may also be located within the first layer of concrete. Some embodiments of the present invention may employ rebar within this first layer of concrete 82 or prestressed composite bands to increase the stiffness and strength of the finished wall panel.
With specific reference to FIG. 8, while the initial layer of concrete 82 is still wet, i.e., not cured, the cavity formers 6 are integrated thereto. More specifically, the cavity formers 6, which may or may not include studs 62, are placed atop the layer of concrete 82 that was initially placed in the form 66. If the cavity formers 6 are included with a plurality of studs 62, the studs 62 would interface with the wet concrete 82, thereby securely fastening the cavity formers 6 thereto. This figure also illustrates how the spacers 34 are used to separate individual cavity formers 6. The spacers 34 may include an interlocking mechanism that helps maintain their orientation in the form when concrete is added thereto. In addition, FIG. 8 illustrates that the protrusion 78 of the side form inner wall 78 is adapted to engage spacers 34 that extend from a cavity former 6 to position the cavity formers 6 within the form 66.
Referring now specifically to FIG. 9, once the cavity formers 6 are placed within the form 66, a second layer of concrete 82 is added to the form 66. Here, it is easily seen how the apertures in the spacers 34 allow for concrete 82 to pass beneath the spacer 34, thereby forming a continuous rib 38 through the thickness of the finished wall panel 2. It is also shown that during formation, substantially no concrete 82 enters the cavity 10 provided by a cavity former 6, thus reducing the density of the wall panel 2. In addition, since the cavity formers 6 are reinforced, they resist deflection when the second layer of concrete 82 is added to the form 66. The cavity formers 6 of various embodiments of the present invention include a roughened outer surface to enhance the bond between the concrete 82 and the EPS foam insulation 14. As one skilled in the art will appreciate, an enhanced bond increases the sheer transfer performance of the wall panel 2.
Referring now to FIG. 10, a method of transporting a plurality of cavity formers 6 is shown. In order to facilitate transportation of a plurality of cavity formers 6 from the location where they are fabricated to the location where they will be integrated into a wall form, the cavity formers 6 of one embodiment of the present invention are designed to be nested together to decrease their shipping envelope, thereby potentially decreasing shipping costs.
Referring now to FIG. 11, integration of a plurality of cavity formers 6 onto a manufacturing form 66 is provided. In operation, once the first layer of concrete 82 is laid in the form, a cart 90 holding a plurality of stacked cavity formers 6 is transitioned over the form 66. A ramp 94 may be provided that aids in positioning the cavity formers 6 on the concrete 82. The ramp 94 may be positioned such that it does not touch the first layer of concrete 82. This system allows for the plurality of cavity formers 6 to be quickly laid on the wet concrete 82 prior to the addition of the second layer of concrete to form the wall panel. After the concrete is poured and sufficiently cured, the forms may be removed to yield a wall panel, which may then be cut to the preferred size.
Referring now to FIGS. 12-15, another embodiment of the cavity former 6 is provided herein. Here, the cavity former 6 that defines a single cavity 10 is provided that includes discreet spacers 34 positioned on the legs 30 thereof. The spacers 34 are adapted to engage spacers of an adjacent cavity former to provide the requisite spacing between adjacent cavity formers 6 so that concrete can flow between adjacent cavity formers to form ribs 38 through the thickness of the concrete wall. With specific reference to FIG. 14, the cavity formers 6 comprise planar surfaces 26 with legs 30 that extend therefrom. The legs 30 may also include plastic studs 62 for interconnection with the wet concrete in the form, as described above. The cavity former 6 also includes reinforcing mesh 18 within the thickness of the planar surface.
Referring now to FIGS. 16 and 17, the mold 22 for forming the embodiments shown in FIGS. 12-15 is shown. This mold 22 is very similar to that described above, wherein a roll 50 is used to dispense a sheet of reinforcing mesh 18 between an upper mold 54 and a lower mold 58. The lower mold 58 in this embodiment of the present invention includes voids 98 that define the spacers after molding completed. Once the mold halves are closed, the reinforcing mesh 18 is positioned approximately between the upper surface 102 of the lower mold 58 and the lower surface 106 of the upper mold 54. Thereafter, molten EPS is added to the mold 22, which heats the PVC coating of the reinforcing mesh 18, thereby enhancing bonding therebetween. As alluded to above, the surfaces of the mold 22 may be roughened such that the finished cavity former is adapted to bond securely with the concrete to increase the sheer performance of the finished wall panel
Referring now to FIGS. 18-20, as descried above, a plurality of cavity formers 6 are added to a form 66 that included a layer of reinforced concrete 82. Thereafter, a second layer of concrete 82 is added to the form 66, which, in light of the spacers 34, is able to occupy the space between adjacent legs 30 of adjacent cavity formers 6 to form ribs 38 that extend through the thickness of the wall panel 2. The cavity formers 6 are stiffened in this embodiment of the present invention to resist the weight of the second layer of concrete 82, thereby providing uniform cavities 10 within the wall panel 2.
Referring now to FIG. 21, this embodiment of the present invention is also adapted to be stacked in a nested fashion, thereby decreasing the shipping envelope of a plurality of cavity formers 6.
Referring now to FIG. 22, a cart 90 with a ramp 94 is shown that supports a plurality of cavity formers 6. The cavity formers 6 are placed on a form 66 that contains a first layer of concrete 82. After a wall panel is formed, it may be cut to size depending on the building requirements.
Referring now to FIGS. 23-33, yet another embodiment of a cavity former 6 is provided. More specifically, this embodiment of a cavity former 6 is very similar to those described above that include a planar surface 26 with legs 30 extending therefrom. However, this embodiment of a cavity former 6 includes end walls 110 that help prevent concrete from infiltrating the cavity 10 provided by the cavity former 6. This embodiment of the present invention also includes a lip 114 that extends from the legs 30 end walls 110 that provides a location for a seat 118 for the receipt of reinforcing members, such as rebar that will be situated within the ribs, for example, of the finished wall panel. The lip 114 also provides a spacing function such that the lip of adjacent cavity formers 6 touch, thereby setting the width of the rib that will be formed in the wall. The lip 114 that spans at least a portion of the leg 30 of the cavity former 6 may also be included with a plurality of rebar seats 118 for securing the reinforcing bar. A plurality of ports 122 may be provided within the legs 30 that are generally plugged. Further, the cavity former 6 may include a groove 148, which may have a plurality of seats 118, for receipt of a reinforcing members 86 to reduce shrinkage stress. In operation, prior to the introduction of concrete to the form, the plugs may be removed from the ports 122 to allow for the incorporation of a conduit or utility line. After the concrete is placed to the form and the finished wall panel is fabricated, the conduit would then be firmly positioned within the thickness of the wall and would be able to receive power, water, or other type of utility cables or lines.
Referring now specifically to FIGS. 31-33, the interconnection of two cavity formers 6 of the type shown in FIGS. 27-30 is shown. More specifically, the lips 114 adjacent the cavity formers 6 are joined, thereby aligning their respective seats 118. Since these embodiments of the present invention employ seats with 90 degree grooves 130 to receive rebar or reinforcing materials, the placement of an adjacent seat define a 180° groove 130 that can adequately support a reinforcing member. These figures also show that the ports 122 of adjacent cavity formers 6 are generally aligned such that removal of their plugs will provide space for a continuous conduit through the concrete, cavity former legs 30 and ribs 80 of the finished wall panel. As succinctly shown in FIG. 32, the seats 118 positioned near the end wall 110 of each cavity former 6 are uniquely positioned to receive and locate a reinforcing bar that will be positioned horizontally along the wall panel after fabrication. It is envisioned that such reinforcing members may be added to the top and bottom of the wall panel and may be tensioned during concrete placement to provide a prestressed, strengthened low density wall panel. It is also contemplated that the cavity formers 6 be reinforced, as described above, to resist the weight of the concrete when it is introduced into the form. One skilled in the art will also appreciate that during forming, a layer of malleable material, such as Sheet-Crete may be added prior to the placement of a series of cavity formers 6, thereby providing an insulated interior wall panel.
Referring now to FIGS. 34-41, yet another embodiment of the insulating cavity former 6 is shown. More specifically, the cavity former 6 shown includes legs 30 and a planar surface 26 wherein the planar surface 26 extends beyond the legs 30 to form a lip 114 about the peripheral edge of the cavity former 6. A plurality of seats 118 are provided on the lip 114 that may include an arcuate profile for the receipt of reinforcing members 86, as described above. The legs 30 also include a plurality of ports 122, which may be plugged, to allow for the integration of conduit. The legs may be supported by the addition of a plurality of gussets 134 that are situated along the length of the cavity former 6. In addition, embodiments of the present invention employ a plurality of clips 136, preferably made of carbon fiber, positioned within the lip 14 for interconnection to concrete 82. The clips 136 are generally comprised of carbon fiber, but may also be comprised of fiberglass, metal, plastic materials and other materials known in the construction trade.
Referring now specifically to FIGS. 36-41, the formation of a wall panel using this embodiment of the present invention is provided. As described above, the cavity former 6 may include reinforcing mesh 18 to increase structural integrity. In addition, a plurality of clips 138 may be included along the lip 114 of the cavity former 6. The clips 136 are integrated into the concrete wall mold during production and preferably extend below the cavity former 6 and above the cavity former 6. In operation, a first level of concrete 82 is placed in the form. Thereafter, a plurality of cavity formers 6 are placed in the form wherein the lips 114 of adjacent cavity formers 6 contact each other to define a rib space 38 (see FIG. 41). When the cavity formers 6 are placed on top of the wet concrete 82, the clips 138, positioned below the cavity formers are inserted into the concrete 82, thereby securing the cavity former 6 to the first layer of concrete 82. Next, a plurality of reinforcing members 86 are added to the form. With specific reference to FIG. 40, reinforcing members 86 are placed on the seats 118 provided above and below the cavity formers 6. In addition, a rebar bridge 142 may be added to the reinforcing material 86 to facilitate placement of the reinforcing member 86 between adjacent cavity formers 6. That is, cavity formers 6 of one embodiment of the present invention provide a gap of a specific width to define a rib 38 in the finished concrete wall. The rebar bridge 142 having slightly greater width than the gap is interconnected to the reinforcing member 86 and the assembly is placed within the gap. Since the rebar bridge 142 has a greater dimension than the gap, the reinforcing member will be situated in a predetermined location to provide ideal strength characteristics. After the reinforcing members 86 are situated within the form, another layer of concrete is placed within the form.
Placement of concrete 82 between adjacent cavity formers 6 the concrete will create ribs in the wall panel. As mentioned above, the clips 138 include a portion that extends above the lip 114, which will be covered bythe concrete as it is introduced between adjacent cavity formers 6. Thus structural integrity is provided between the formed rib 38 and the portion of the wall panel initially placed.
In one embodiment of the present invention, during fabrication the concrete 86 is placed adjacent to an upper surface 146 of the cavity former 6. Thereafter, the wall panel is allowed to cure and transported to the work site. After the wall panel is erected, an interior hollow wall is provided that consists of the inner surface of the cavity former 6, which allows integration of various utilities within the length and width of the wall panel. After all of the required utilities are included into the wall panel, additional insulation, either expanded foam, fiberglass, etc. maybe added to the cavity provided by the cavity former 6. Finally, a sheet of drywall or other internal building material, may be interconnected to the upper surface 146 of the wall panel to complete the wall panel assembly.
Referring now to FIGS. 42-51, yet another embodiment of an insulating cavity former 6 is provided that is very similar to that provided in FIGS. 36-41. However, in this embodiment, the lip 114 extends only from the end walls 110 and one leg 30 of the cavity former 6. As succinctly shown in FIG. 49 a channel 150 is provided along the length of the cavity former 6 such that when a plurality of cavity formers 6 are engaged, the end of a lip 114 would fit into the channel 150 provided. This configuration has the advantage of interlocking adjacent cavity formers 6 together when they are placed upon an initial layer of concrete, for example. This embodiment of the present invention also includes at least one groove 148 located along the width of the cavity former 6. The groove(s) 148 is similar to the seats 118 provided along the lip 114 of the cavity former 6 such that the groove 148 provides a location for the integration of a reinforcing member 86 during fabrication (See FIG. 45).
With specific reference to FIGS. 44-47, fabrication of a concrete wall initially proceeds with placing a layer of concrete 82, or in some instances, nailable fibrous concrete 152 into a form. Thereafter, the cavity formers 6 are placed a top the fibrous concrete 150 such that the clips 138 provided within the lip 114 embed themselves within the fibrous concrete layer 152. The clip 138 may be associated with a slot 156 that reduces the distance between the concrete 82 or fibrous concrete initially placed in the form, thereby enhancing load transmission through the thickness of the wall panel. In addition, a reinforcing member 86 may be integrated into the fibrous concrete layer 152 and situated within the groove 148 provided by the cavity former 6. One skilled in the art will appreciate that when a plurality of cavity formers 6 are situated side-to-side within a form, the reinforcing member 86 would tie them together. After the cavity formers 6 are placed within the form, a plurality of reinforcing members 86 are situated on the seats 118 provided which are succinctly shown in FIG. 50. Thereafter, concrete 82 introduced to the form above, below and in between the cavity formers 6. The concrete 82 between adjacent cavity formers provides ribs within the finished wall panel. As above, the clips 138 then structurally interconnect the concrete 86 and the fibrous concrete 152 through the thickness of the wall panel.
Referring now to FIGS. 52-62, yet another embodiment of a cavity former 6 similar to that described above having a non-continuous lip 114 is provided. The major difference between this embodiment and that of FIGS. 42-48 is that a plurality of shear nails 160 are employed as opposed to clips. In addition, the shear nails 160 rest in a plurality of slots 156 integrated into the lip 114. The slots 156 allow concrete 82 that is placed above, below and between adjacent cavity formers 6 to contact the concrete 82 originally placed with the form to form a continuous load path through the thickness of the wall panel. The shear nails 160, which are preferably constructed of polypropylene, carbon fiber, metal or fiberglass, include a plurality of arms 164 that pierce the initial layer of concrete or fibrous concrete 152, placed in the form and the concrete 82 placed above the lips 114 of the cavity former 6 that define the top, bottom and the ribs of the finished wall panel. Preferably, a locator 168 is provided that stabilizes and maintains the shear nail 160 within the slot 156.
Referring now to FIGS. 63-83, still yet another embodiment of the present invention is shown that is very similar to those previously described that employs a mechanism for tying the cavity former 6 into the initial layer of concrete 82 or fibrous concrete 152 placed within the form. Here, the cavity former 6 includes a lip 114 that at least is positioned about three sides of the cavity former 6. Instead of employing a clip or a shear nail, this embodiment of the present invention employs a pin 172. Although the pin 172 is preferably constructed of a polypropylene material, one skilled in the art will appreciate that many other materials may be employed without departing from the scope of the invention. The pin 172 is adapted to situate the cavity former 6 on the initially placed material in the form and provides the mechanism that binds the cavity former 6 onto the initially placed material. A channel 150 may also be included that provides interlocking relationship between a cavity former 6 and the lip 114 of an adjacently placed cavity former 6. Creation of a wall panel is similar to that described above wherein the pins 172 of the cavity formers 6 are then placed within the still wet first layer of concrete 82 or fibrous concrete 152. Thereafter, concrete 82 is introduced to the form and is allowed to fill the voids between adjacent cavity formers 6 and above and below the cavity formers 6. Concrete is also allowed to fill the voids defined by the slots 156 to create a continuous structural load path between the initially placed fibrous concrete 152 and the subsequently placed concrete 82. In order to prevent concrete 82 from entering the void provided by the cavity former 6, a film 176, preferably of biaxially-oriented polyethylene terephthalate (boPET) polyester film, i.e. Mylar®, may be interconnected to the upper surface of the cavity former 6.
Referring now again to FIGS. 1-83, the cavity formers 6 of embodiments of the present invention are made of an insulative material, preferably expanded polystyrene foam (EPS). One skilled in the art will appreciate that other insulated materials, such as extruded polystyrene foam (XPS) may be employed as well. In operation, EPS pellets are taken from a hopper, heated and introduced into the form 66 that contains the reinforcing mesh 18. In one embodiment of the present invention, the EPS is shaped by pumping warm prepped polystyrene beads into a closed cavity heated mold then chilled to cure the polystyrene beads into a predetermined shape. The mold may impart a surface texture onto the cavity former 6. For example, small irregular shaped holes may be added to the surfaces of the cavity former that will enhance the bond between the concrete and the cavity former 6.
Embodiments of the present invention employ any number of reinforcing members 18 into the mesh. Preferably, fiberglass is utilized that is coated with polyvinyl chloride (PVC). The heat of the molten EPS is, in some embodiments, approximately equal to the melting point of PVC, thereby melting the PVC and mechanically and/or chemically bonding it to the EPS. This marriage of PVC and EPS results in a composite insulated material with enhanced strength that allows for the individual thicknesses of planar surfaces 26 and legs 30 to be decreased, thereby decreasing the costs and weight of the cavity former 6 while maintaining the strength. Alternatively, carbon fiber mesh may be added to the EPS foam to provide rigidity. Other materials that would provide rigidity are also contemplated by embodiments of the present invention and which one skilled in the art will appreciate could be used. In addition, many materials may be used with or without the coating of PVC. Further, one skilled in the art will appreciate the fiber orientation of the reinforcing mesh may be altered depending on the final use of the reinforced insulation. Preferably, a fiberglass fiber is used as oriented at 0 and 90 degrees thereby providing approximately a square mesh. Alternatively, mesh may be woven or positioned at 45 degree angles thereby providing a diamond sheet to be used within the thickness of the insulation. Embodiments of the present invention include reinforcing members 18 that are tensioned during molding to yield a pre-stressed cavity former 6.
While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims.
