The present invention relates to the building construction industry, and more particularly to the construction of unitized curtain walls for cladding a building skeleton framework.
The development of skeleton framework structural support for buildings in the late nineteenth century created the field of non-load-bearing curtain wall systems, and particularly unitized curtain wall systems. Unitized curtain walls entail factory fabrication and assembly of panels and may include factory glazing. These completed units are hung on the building structure to form the building enclosure. Many early examples of curtain walls involved glass or stone panels framed by mullions. Of late, unitized curtain wall, comprised of composite factory-made panels, has the advantages of: speed; lower field installation costs; and quality control within an interior climate controlled environment. The economic benefits are typically realized on large projects or in areas of high field labor rates. The prior art includes a variety of complex fastening and support systems used to connect such panels together. A common system for connecting panels involves the use of pegs or clips that extend outward from inside an edge of an upper panel, for mating with notches in the panel immediately beneath. This type of system requires great precision in the placement of pins and notches so that they will mate, which may be thwarted in the field where adjustments may be required. This system also concentrates the load of a panel into the notches below, which could break under the stress. One such system is disclosed in U.S. Pat. No. 5,067,300 to Takeda.
U.S. Pat. No. 7,810,288 to Lechasseur attempts to address these issues with a cladding system comprised of flanged panels attachable to the supporting structure, leaving gaps between the panels which are then filled with deformable mouldings. A panel of this system includes a pre-finished exterior sheet of material such as aluminum and a core of trusses, ribs or honey comb structure. Mounting the panels on the supporting structure involves specially designed mounting clips, furring strips, furring attachment flanges, furring spacing segments, special corner mouldings, moulding legs, forks insertable into the panel cores, and overall is rather complicated.
U.S. Pat. No. 6,098,364 to Liu teaches adjustable connections of cladding panels to the supporting building structure. All of the load of the panels is transmitted to the building framework through the adjustable connections The prefabricated panels comprise two layers of “any material” (sic), joined with silicone adhesive. It can be inferred that only materials with some tensile strength could be used in this system, such as fiberglass, which is relatively expensive.
Accordingly it is an object of this invention to utilize prefabricated panels made of reinforced concrete, which is very strong, relatively inexpensive compared to glass, stone, metal or fiberglass, and does not involve mullions. Another object is to provide for simple, adjustable connection means between adjacent panels and to the concrete foundation of the building structure. A further object of the invention is to provide a panel system the load of which is borne by the foundation. Still another object is to tie together the reinforcing rods of each panel to adjacent panels and to anchor the entire cage of reinforcing rods to the foundation. Yet another object is to means of adjusting the fit of panels together to compensate for minor deviations in the dimensions and elevations of construction elements.
The present invention is a prefabricated curtain-wall system made of reinforced concrete panels. The reinforced concrete is comprised of a grid of horizontal and vertical rods, tied together where they meet. Connection between two adjacent panels utilizes an external bracket with two bolts, each bolt mating with a nut protruding from a slotted bracket embedded in each of two adjacent panels. The embedded brackets have eyelets for passage of a rod of the reinforcing grid. The lowermost panels of the system are anchored to the building foundation, thus the load of the entire curtain wall and the embedded reinforcing can be transmitted to the foundation. Further, this system allows for field adjustment of panels, both vertically and horizontally, to compensate for inconsistencies in foundation heights and plumbness of building skeletons.
With reference to the drawings, a detailed description of the best mode and preferred embodiment of the present invention ensues, with the understanding that the disclosed embodiment is merely one example of the invention which could be embodied in additional forms. Therefore, specific structure and functional details disclosed herein should not be interpreted as limiting, but solely as a basis for the claims and as a representative basis for teaching someone skilled in the art to variously employ the present invention in an appropriate structure.
In general the invention comprises a pre-fabricated planar concrete panel 1, having internal embedded grids of reinforcing steel rods 6 and embedded anchoring hardware, and an assembly of such panels 1 to form a curtain wall system as the exterior of a steel-framed building, including a multi-story building. As seen in
The embedded vertical and horizontal reinforcing steel rods 6 are secured into a fixed grid, as shown in
Near the top of panel 1, embedded vertical reinforcing rods 6 pass through another embedded bracket 3.
Connecting stacked lower and upper and lower panels 1 involves 2 should be panels 1 involves fastening embedded angle bracket 16 to angle brackets 17 with ordinary bolts 4 and hex nuts 20, again mating a horizontal slot with a vertical slot to allow tolerance for adjusting the fit. Running the embedded grid of steel reinforcing rods through all embedded anchoring hardware ensures the integrity of the assembly of panels 1.
To fasten panels 1 to the steel skeleton of a building, a threaded steel rod 18 is screwed into special wing fastener 11.
This application claims the benefit of a provisional application, Ser. No. 61/283,585, filed Dec. 7, 2009.
| Number | Date | Country | |
|---|---|---|---|
| 61283585 | Dec 2009 | US |