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RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Application No. 60/857,863, filed on Nov. 10, 2006. The entire teachings of the above application are incorporated herein by reference. 

   BACKGROUND 
   Strong winds from hurricanes or tropical storms carry debris, which can cause heavy damage to windows and glass doors. Building owners typically cover windows and doors when a hurricane or tropical storm approaches with a barrier to prevent debris from hitting the glass surfaces. In the past, these barriers have either been disposable (e.g., plywood) or unsightly (e.g., a rollaway or slideaway screen permanently mounted to the door or window). 
   SUMMARY 
   Embodiments of the invention feature a portable, quick mounting, easily removable, and convenient-to-store security barrier that can protect an opening to a building, such as a window or sliding glass door, from breakage due to the hazard of flying debris caused by powerful winds generated by hurricanes and tornadoes. In conjunction with these catastrophes, an advantage of the invention is that is also offers a security benefit as a deterrent to home invasion by restricting breaking and entering through windows or sliding glass doors. 
   An embodiment of the invention comprises multiple panels that can be nested together when stacked for storage. The panels are easily and quickly installed and removed from a building window or other opening. In some embodiments, the panels are installed by inserting one end into slots attached to the building and installing the other end via anchoring bolts to a surface of the building. The panels may install in the slots via pins attached to the panels and the anchoring bolts may pass through the flanges on an opposite side of each panel. In some embodiments, the panels may be connected together via flanges and pins, such as clevis pins. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing will be apparent from the following more particular description of example embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the present invention. 
       FIG. 1  illustrates an embodiment in which three panels are installed in front of a sliding door of a building; 
       FIG. 2A  shows two panels of the embodiment of  FIG. 1  in a perspective view; 
       FIG. 2B  shows an enlarged view of a panel foot of the embodiment of  FIG. 2A ; 
       FIGS. 3A-3B  show the top portion of a panel and a side view of a pin of the embodiment of  FIG. 1 ; 
       FIGS. 4A-4C  illustrate a slotted rail according to the embodiment of  FIG. 1 ; 
       FIG. 5  illustrates the panels of the embodiment of  FIG. 1  in an uninstalled and nested configuration for storage; 
       FIG. 6A  illustrates an optional variation of the embodiment of  FIG. 1  wherein one of the panels incorporates an escape door; 
       FIG. 6B  shows an enlarged view of a panel foot of the embodiment of  FIG. 6A ; 
       FIG. 6C  shows an enlarged side view of a triangular wedge pin of the embodiment of  FIG. 6A ; 
       FIG. 7  illustrates a side view of the optional door shown in  FIG. 6 ; 
       FIG. 8  illustrates a second embodiment in which three panels of equal width are installed in front of an opening of a building; 
       FIG. 9  illustrates the panels of the embodiment of  FIG. 8  in an uninstalled and nested configuration for storage; 
       FIGS. 10A-10B  illustrate a bracket plate of a third embodiment configured to be mounted to the side of a building; and 
       FIGS. 11A-11B  illustrate a bracket of the embodiment of  FIGS. 10A-10B  that interfaces with the bracket plate. 
   

   DETAILED DESCRIPTION 
     FIG. 1  illustrates one embodiment of the present invention  100  in an installed configuration. In this embodiment, three panels  102 ,  104 ,  106  cover a sliding glass door  108  when installed. Each panel  102 ,  104 ,  106  includes a rectangular frame with a screen  122  covering the open area inside the frame. Each panel has a pair of pins  110  at the ends of a top side and a pair of anchoring flanges  112  at the ends of a bottom side. The pins  110  interface with a rail  118  installed in the wall  120  above the sliding door  108  and the anchoring feet interface with the ground  116  via bolts  114 . Note that the panels  102 ,  104 ,  106  may alternatively be installed with the pins  110  (and rail  118 ) at the bottom and the anchoring flanges  112  and bolts  114  at the top being installed in the wall  120  of the building. While the embodiment shown in  FIG. 1  has three panels, other embodiments may have a fewer or greater number of panels. 
   Each of the panels may be constructed from a number of materials, such as high-impact plastic, aluminum, steel or stainless steel, or a combination of materials. Materials that offer high strength and relatively low weight are preferable, but not required. 
     FIG. 2A  illustrates panels  104 ,  106  in accordance with an embodiment of the present invention in perspective view. As can be seen, the pins  110  extend directly above each panel  104 ,  106  on frame elements  202  and  210 . The anchoring feet  112 , enlarged in  FIG. 2B , extend from each panel  104 ,  106  on the opposite frame elements  206  and  214 . The anchoring feet  112 , however, extend out to the side of each panel  104 ,  106 . In this embodiment, the anchoring feet  112  extend from each panel  102 ,  104 ,  106 . Panels  104  and  106  in this embodiment also have optionally included locking flanges  218  on frame elements  204 ,  208 , and  216 . The locking flanges  218  are connected via pins, such as clevis pins, or bolts (not shown) after the panel pins  110  and anchoring flanges  112  have been installed. Two locking flanges  218  between each panel are shown in this embodiment, but more or fewer flanges may be used. 
     FIG. 3A  illustrates pins  110  of panel  102  in accordance with an embodiment of the present invention.  FIG. 3B  shows that each pin  110  of the embodiment has a triangular cross-section with angled faces  302  and  304 . The angled faces  302  and  304  converge at an apex  312 . 
     FIGS. 4A-4C  illustrate the rail  118  with slots  402  in accordance with an embodiment of the present invention. The rail  118  has slots  402 , which have angled faces  404  and  406 , which match the angled faces  304  and  306  of the pins  110 . The angled faces  302 ,  304 ,  404 , and  406  firmly hold the pins  110  in the slots  402  when the pins  110  are fully inserted in the slots  402 . However, the angled faces  302 ,  304 ,  404 , and  406  also allow the panels  102 ,  104 ,  106  to be pivoted about the apex  312  of each pin  110  when the pins  110  are partially inserted in the slots  402 . 
     FIGS. 4B and 4C  illustrate a rail  118  made of solid material, wherein the slots  402  are formed by cutting out portions of the solid material. Alternatively, the rail  118  could be formed of a tubular material, such as a stainless steel or aluminum tube wherein the tube wall has a square cross-section. The slots  402  would be formed by cutting out portions of tube wall. The pins  110 , in this alternative embodiment, would be inserted through the slots  402  and be contained within the hollow space of the tubular rail  118 . 
   Returning to  FIG. 2 , since the anchoring flanges  112  and the locking flanges  218  extend from each panel  104  and  106 , neatly stacking the panels would be difficult if the panels were all the same size because certain features that protrude from each panel  102 ,  104 ,  106 , such as anchoring flanges  112 , would interfere with each other, preventing the panels  102 ,  104 ,  106  from resting flat against each other. However, the three panels illustrated in the embodiment in  FIG. 1  are each a different width. The top frame element  306  and bottom frame element  312  of the first panel  102  (as shown in  FIG. 6 ) are longer than the top frame element  202  and bottom frame element  206  of the second panel  104  (as shown in  FIG. 2 ), which are longer than the top frame element  210  and bottom frame element  214  of the third panel  106  (as shown in  FIG. 2 ). 
     FIG. 5  illustrates the three panels  102 ,  104 ,  106  of the described embodiment stacked together in a nested configuration  500  for storage. Because panel  104  is narrower than panel  102 , the anchoring flanges  112  of panel  104  are completely within the span between the anchoring flanges  112  of panel  102 . Likewise, because panel  106  is narrower than panel  104 , the anchoring flanges  112  of panel  106  are completely within the span between the anchoring flanges  112  of panel  104 . Note that the panels&#39; screens  122  (not shown in  FIG. 5 ) must be set within each panel so that they do not interfere with the interlocking flanges  218  when the panels are nesting. 
     FIGS. 6A-C  and  7  illustrate an escape door  602  that may be optionally installed in the above-described embodiment. The escape door  602  is best located in the largest panel  102 , but may be located on any panel  102 ,  104 ,  106 . The escape door  602  comprises its own frame with hinges  606  on one side and a locking latch  604  on the other side. The panel is illustrated as being located completely on the screen  122 , but may also extend to the frame elements of the panel  102 ,  104 , or  106  on which it is mounted. For example, the hinges  606  can be mounted to frame element  308  of panel  102  and the latch may interface with frame element  310 . 
     FIG. 7  also illustrates the anchoring flanges  112  attached to the bottom frame element of panel  102  in this embodiment. Bolts  114  extend through the portion of the anchoring flanges  112  extending from the panel. Optionally, the bolts may incorporate a security interface that requires a unique tool, such as a keyed wrench or screwdriver, to remove the bolts, thereby increasing the security provided by the screen. 
   Typically, the anchoring flanges  112  would rest on a floor surface, such as a concrete slab, and the bolts would interface with corresponding holes in the floor surface.  FIGS. 10A-B  and  11 A-B illustrate an alternative embodiment in which the anchoring flanges mount to a bracket.  FIGS. 10A and 10B  illustrate a bracket plate  1000  that would be permanently mounted above or below a window or a door. The bracket plate  1000  is mounted to the wall with screws or bolts (not shown) through holes  1004 . The bracket plate has two flanges  1006 ,  1008 . In the illustrated embodiment, flange  1008  is longer than flange  1006 . However, flanges  1006 ,  1008  may be equal in size. 
     FIGS. 11A and 11B  illustrate a bracket  1100  that interfaces with the bracket  1000  via slider plate  1102  and tabs  1104 ,  1106 . Tab  1104  interfaces with flange  1006  and tab  1106  interfaces with flange  1008 . The brackets  1100  slide in bracket plate  1000  to be positioned beneath anchoring flanges  112  of a panel. The flat surface of an anchoring flange  112  is then adjacent to plate  1108  of bracket  1100 . Bolts  114  are passed through the anchoring flange  112  and into holes  1110  of bracket  1100 . Such a bracket system, or an equivalent, allows a panel to be mounted at some height above the ground. 
   The embodiment described above with respect to  FIGS. 10 and 11  illustrates a panel system in which the pins  110  are mounted above the opening to be protected and the anchoring flanges  112  are mounted below the opening. As mentioned earlier, the panels optionally can be mounted upside-down, wherein the pins  110  are mounted beneath the opening to be protected and the anchoring flanges  112  are mounted above the opening. In such an alternative embodiment, rail  118  is mounted below the opening. Pins  110  are located at the bottom of panels  102 ,  104 ,  106  and are lowered into slots  402 . The panels  102 ,  104 ,  106  are then pivoted about the pins  110  to bring the anchoring flanges  112  into position for fastening to the building. In conjunction with the embodiment shown in  FIGS. 10 and 11 , the bracket plate  1000  and brackets  1100  can be located above the building opening to be protected and anchoring flanges  112  would bolt to the brackets  1100 , which are located above. Alternatively, the anchoring flanges, in this embodiment, can be oriented such that they rest against the side of the building and bolt directly to an interface (not shown) mounted to the side of the building. 
     FIGS. 8 and 9  illustrate an alternative embodiment  800  of the present invention. Like the first embodiment described above, this embodiment utilizes three separate panels  802 ,  804 , and  806 . However, the three panels include identical dimensions of height and width. In this embodiment, the pins  110  are positioned in the ends of top frame elements  804  and the anchoring flanges  810 ,  812 , and  814  are located on the opposite bottom frame elements  816 ,  818 , and  820 . However, the anchoring flanges  810 ,  812 , and  814  are located at different positions on each panel  802 ,  804 , and  806 . On panel  802 , the anchoring feet  810  are located at the ends of frame element  816 . On panel  804 , the anchoring feet  812  are located a distance inboard from the ends of frame element  818 . On panel  806 , the anchoring feet  814  are located a further distance inboard from the ends of frame element  820 . 
     FIGS. 8 and 9  also show optionally-included locking flanges  806  and  808  which differ from the first embodiment in two ways. First, the flanges sit completely outside the perimeter of each panel  802 ,  804 , and  806 . Second, the locking flanges  806  and  808  vary in location between each panel.  FIG. 8  shows locking flanges  806  between panels  802  and  804  and locking flanges  808  between panels  804  and  806 . There are two locking flange pairs between each pair of panels. The locking flanges  806  between panels  802  and  804  are each higher than the respective locking flanges  808  between panels  804  and  806 . 
     FIG. 9  shows that when panels  802 ,  804 , and  806  are in a stacked configuration  900 , they nest with the anchoring flanges  812  within anchoring flanges  810  and anchoring flanges  814  within anchoring flanges  812 . The locking flanges  806  and  808  rest outside the perimeter of each panel  802 ,  804 ,  806 . Also, because the locking flanges  806  and  808  are located on panels  802 ,  804 ,  806  at different heights, they do not interfere with each other when the panels  802 ,  804 , and  806  are in the nested configuration  900 . 
   While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.

Summary:
An apparatus for covering an opening of a building comprising a plurality of rectangular panels. The panels are sized such that when they are stacked for storage, the panels nest together.