Patent Publication Number: US-2007107328-A1

Title: Panel attachment system

Description:
REFERENCE TO RELATED PATENT APPLICATION  
      This application is a continuation in part of U.S. patent application Ser. No. 11/254,734 filed on Oct. 21, 2005, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates generally to panel structures for covering exterior building openings (windows, doors, etc.) for protection from inclement weather, and particularly to a panel attachment system for the removable attachment of protective panels over building openings, e.g., in the manner of storm windows and the like.  
      2. Description of the Related Art  
      High winds and severe weather can occur in many parts of the country during certain seasons of the year. Such conditions can be sufficiently prevalent to cause governing bodies to create standards for wind and storm protection in such areas. Examples of the above are found in the Florida State Building Code, which refers back to ASTM E 1996 test standards for large missile impact (i.e., windblown objects). In such areas, it is generally required that openings (doors, windows, etc.) of building structures be covered or secured when a hurricane or similar extreme wind condition is imminent in order to reduce damage to the structure, as well as to reduce the danger from flying shards of glass.  
      Accordingly, a number of different systems have been developed to meet these standards and to minimize damage to buildings and other structures when such extreme conditions occur. The most basic weather protection system essentially comprises the use of plywood or other wood sheets nailed in place over the door and window openings of a structure. Plywood or similar material of sufficient thickness ( 7/16 inch or thicker) is considered sufficiently strong that it is deemed to meet the ASTM E 1996 test standards for windborne debris. While the installation of plywood or similar panels is effective if carried out properly, such wood panels are relatively heavy and cumbersome, and their removal after the storm has passed leaves nail holes in the structure, which can lead to further damage in tropical and subtropical climates having high humidity and wood boring insects.  
      As a result of the above, various other protective systems were developed, which do not require the use of nails or similar fasteners that must be removed after penetrating the wood structure. An example of such is permanently installed hinged shutters, which are closed over the window or door openings as needed and reopened when the hazard has passed. While shutter systems can be effective, they can also be unsightly and costly to install, and there is often insufficient room to allow the shutters to fold back along the side of the structure. Moreover, they are not suited for relatively wide spans.  
      In response to the problems of temporarily attached wood panels and shutter systems, various permanently mounted brackets and the like have been provided, with panels temporarily securing to or within the brackets. This obviates the problem of removal of the fasteners (nails, etc.) from their penetration into the structure, while also avoiding the problems associated with shutter systems. However, such systems known to the present inventor tend to use relatively complex and costly panel configurations (extruded or otherwise specially formed metal, etc.), and/or require special, costly edge components for the panels, which in turn attach to specialized and costly attachment fittings permanently secured to the structure. Moreover, such systems can be relatively complex and time consuming to install and remove, even though their attachment fittings do not require removal from the building structure.  
      Thus, a panel attachment system solving the aforementioned problems is desired.  
     SUMMARY OF THE INVENTION  
      The panel attachment system has opposed upper and lower extruded tracks or channels, which attach along the upper and lower edges of a window or similar opening in a structure, and one or more panels removably secured to the tracks to protect the opening from extreme weather conditions. The upper track has a generally “h” shaped cross section, with the taller flange being secured permanently to the structure (window frame, etc.), and the channel of the track defined by the two depending legs of the “h” serving to hold the upper edge of the panel in place. The lower track has an “F” shaped cross section, with the wider flange again serving to secure the track permanently to the structure and the two parallel arms of the “F” defining a track channel having retaining lips extending therefrom and holding the heads of a series of threaded fasteners therein. The lower edge of the panel includes a corresponding series of holes therethrough, which fit over the protruding shanks of the fasteners and are secured to the fasteners by cooperating nuts. The opposite lateral or vertical edges of the panel may be secured to the corresponding edges of the opening by a series of flush or protruding fasteners, depending upon the installation.  
      The panels are preferably formed of corrugated sheets of high-impact plastic material, e.g., high density polypropylene or the like. Such corrugated plastic sheet provides good strength due to the thickness and spacing of the corrugations, while still being relatively lightweight. Other types of plastic or composite material may be used as desired, but it has been found that the use of corrugated polypropylene plastic material of about ⅝ inch thickness provides good economy while meeting the ASTM E 1996 and Florida State Building Code requirements. Two or more such panels may be joined edge-to-edge to cover a wider opening by means of an appropriately configured extrusion that grips one panel edge and receives the adjacent panel edge.  
      These and other features of the present invention will become readily apparent upon further review of the following specification and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an environmental, perspective view of a panel attachment system according to the present invention as installed, on a building structure, showing its general features.  
       FIG. 2  is an environmental perspective view of a panel attachment system according to  FIG. 1 , showing a first method of attaching the panels to the structure.  
       FIG. 3  is an environmental perspective view of a panel attachment system according to  FIG. 1 , showing an alternative method of attaching the panels to the structure.  
       FIG. 4  is a detailed side elevation view in section of the lower edge of the panel attachment system installation of  FIG. 1 , showing further details thereof.  
       FIG. 5  is a detailed side elevation view in section of the upper edge of the panel attachment system installation of  FIG. 1 , showing further details thereof.  
       FIG. 6  is a detailed top plan view in section of the opposite lateral edges of the panel attachment system installation of  FIG. 1 , showing further details thereof.  
       FIG. 7  is a detailed top plan view in section of the center of the panel attachment system installation of  FIG. 1 , showing further details thereof. 
    
    
      Similar reference characters denote corresponding features consistently throughout the attached drawings.  
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The present invention comprises various embodiments of a panel attachment system adapted particularly for use as storm window panels over door and window openings in building structures, but suitable for use in other environments as well. Upper and lower tracks or channels are permanently installed immediately above and below the structural opening, with one or more protective panels removably secured to the tracks to protect the door or window opening.  
       FIG. 1  of the drawings illustrates an exemplary installation of the panel attachment system, designated generally as system or panel installation assembly  10 . A continuous, generally horizontal lower track  12  is permanently secured to the sill S or lower trim board of the structural opening O by a series of fasteners  14 , e.g., lag bolts, threaded studs and nuts, wood screws, etc. A continuous, generally horizontal upper track  16  is permanently secured to the upper lintel L or trim board of the opening substantially parallel to the lower track  12 , generally using the same type(s) of fasteners  14 . The lower and upper tracks  12  and  16  are preferably formed of aluminum extrusions, but other manufacturing principles may be used to form the tracks  12  and  16 , as desired.  
      One or more panels  18   a ,  18   b , etc., are removably secured over the opening by the two tracks or channels  12  and  16 . The opposite lateral or vertical edges of the panels  18   a ,  18   b  may be secured to the lateral edges E or trim boards of the opening by a series of fasteners (described in detail further below), which are, in turn, permanently installed to the edges E of the structural opening. The panels  18   a ,  18   b , etc. may be formed of any suitable material, e.g., plywood or other composite board, solid or hollow core plastic sheets, composite fibers (e.g., fiberglass), etc., as desired. However, the panels  18   a  and  18   b  are preferably formed of a corrugated polypropylene plastic material, which has been found to provide optimum characteristics of light weight, flexibility, weather and sun resistance, insect resistance, and good resistance to impact by wind blown objects. (The term “corrugated” is used here to describe the configuration of the panels  18   a  and  18   b  as generally having a series of spaced apart internal webs connecting opposed smooth outer surface sheets and defining a series of parallel flutes of rectangular or other cross section therebetween, and is not limited to an internal configuration comprising a continuous web sheet having a series of alternating folds therein.)  
      The material is relatively thick, e.g., on the order of sixteen millimeters, or ⅝ inch, with other thicknesses usable as desired. The relatively thin front and back surfaces allow reasonably good light passage therethrough, with the panels thus being translucent. This provides the advantage of reasonably good natural daylight for the interior illumination of a structure when such panels are secured in place over the structural openings, which can be an important consideration in the event of power failure during a storm.  
       FIG. 4  of the drawings provides a detailed elevation view in section of the lower track or channel component  12 . The lower track or channel  12  has a generally “F” shaped cross section (shown in mirror image in the right hand view of  FIG. 4 ), with an attachment flange  20  forming the vertical component of the shape. The attachment flange  20  has a lower edge  22 , a medial portion  24 , and an upper edge  26 , with a lower rail  28  extending from the medial portion of the flange  20  substantially normal thereto, and an upper rail  30  extending from the upper edge of the flange  20  substantially parallel to the lower rail  28 . Each rail  28  and  30  has a distal lip  32  extending therefrom. The two lips  32  face toward one another to provide a narrower slot  34  therebetween opposite the attachment flange  20 , with a fastener head retaining channel  36  defined between the two rails  28  and  30 , the two lips  32  and the attachment flange  20 .  
      The channel  36  captures the head  38  of a conventional threaded fastener  40  therein, with the two lips  32  precluding departure of the fastener head  38  through the narrower slot  34 . The only means of installing or removing the fastener  40  to and from the lower track  12  is by inserting or removing the fastener head  38  into or from the open end of the track  12 . This allows the position of the fasteners  40  to be adjusted as desired for proper spacing and alignment with preformed holes adjacent the lower edge(s) of the panel(s)  18 . However, the positions of the fasteners  40  in the track  12  may be temporarily or permanently fixed in place, e.g., by adhesive, by staking either or both of the rails  28  and/or  30 , by spacers within the channel  36  between the bolt heads, etc.  
      The threaded shank  42  of the fastener  40  extends outwardly from the channel  36  of the lower track  12 , generally normal to the track attachment flange  20  and to the surface of the structure to which the lower track  12  is secured. The panel(s), e.g., single panel  18  of  FIG. 4 , is provided with a series of preformed lower track attachment holes or passages  44  therethrough adjacent the lower edge  46  thereof corresponding in number to the fasteners  40  installed in the channel  36  of the lower track  12 . The threaded shanks  42  of the fasteners  40  pass through the lower holes or passages  44  of the panel(s)  18 ,  18   a ,  18   b , etc., with the panel(s)  18 ,  18   a ,  18   b , etc. being secured to the fasteners  40  (and thus to the underlying lower track  12 ) by cooperating nuts, e.g., hexagonal nuts  48   a  as shown in  FIG. 4  and the right side of  FIG. 1 , or alternatively by wing nuts  48   b , as shown along the left side of  FIG. 1 .  
       FIG. 5  provides a detailed elevation view in section of the upper track  16  and the installation of the upper edge  50  of the panel  18  therein. The upper track or channel  16  has a generally “h” shaped cross section, as shown in mirror image in the right end elevation view of  FIG. 5 . The track  16  includes an attachment flange  52 , which serves to attach the track  16  to the upper lintel L or trim board of the opening O. The upper track attachment flange  52  has a lower edge  54 , a medial portion  56 , and an upper edge  58 , with a downwardly oriented angle  60  extending from the medial portion of the flange  52 . The angle  60  and lower portion of the attachment flange  52  define a downwardly facing panel edge retaining channel  62  therebetween, which accepts the upper edge  50  of the panel  18  therein. No additional fasteners are required to secure the upper edge  50  of the panel  18  within the channel  62  of the upper track  16 , as the panel  18  cannot drop downwardly from the channel  62  due to attachment of the substantially parallel lower edge  46  of the panel to the lower track  12 .  
      The panel  18 , or plural panel assembly  18   a ,  18   b , etc., may be secured removably to the two tracks  12  and  16  in different ways.  FIG. 2  illustrates a first panel attachment method, in which the panel lower edge fasteners  40  are first installed in the lower track  12  with their threaded shanks  42  extending therefrom. The panel(s)  18   a ,  18   b , etc. are secured in place by first inserting their upper edges  50  into the downward facing channel of the upper track  16 . The opposite lower edges  46  of the panels are then swung inwardly, i.e., toward the wall of the structure and the lower track  12  attached thereto, with the lower edge holes or passages  44  passing over the shanks  42  of the fasteners extending from the lower track  12 . Suitable attachment nuts may then be installed over the ends of the fastener shanks  42  to secure the lower edge(s)  46  of the panel(s) in place. Either the hexagonal nuts  48   a  or wing nuts  48   b  may be used, but preferably wing nuts  48   b  are used in this installation method, as the nuts must be installed and removed individually at each installation and removal of the panels  18 ,  18   a ,  18   b  from the structure. The use of wing nuts facilitates this task and obviates the need for additional tools or equipment.  
       FIG. 3  illustrates an alternative panel installation method in which the lower edge fasteners  40  are left permanently installed through the lower edge of the panel  18 , as evidenced by the visible hexagonal nuts  48   a  along the panel lower edge as shown in  FIG. 3 . In this instance, the upper and lower edges  46  and  50  of the panel  18  are simultaneously secured to or within the lower and upper tracks  12  and  16  by sliding the panel  18  to engage the channels of the tracks  12  and  16  from the ends thereof. The heads of the lower track fasteners  40  protrude from the back side of the panel  18 , generally as shown in  FIG. 4 , and are slid laterally into the open end of the channel of the lower track  12  simultaneously with the lateral insertion of the upper edge  50  of the panel into the channel of the upper track  16 . This method has the advantage of obviating any requirement for the installation of additional fasteners along the lower edge of the panel at the time of panel installation, and may be used where there is no protruding structure (e.g., cornices, walls, etc.) immediately adjacent the opening over which the panel  18  is to be secured and extending outwardly from the wall.  
      The panel attachment system  10  also provides for securing the opposite lateral outboard edges of the panel(s) to the structure.  FIG. 6  provides a detailed plan view in section of two exemplary lateral edge-fastening devices, which are also illustrated more generally in  FIGS. 1 through 3 . It will be understood that these two types of lateral edge fasteners may be installed with one another, as shown in  FIG. 6 . However, preferably only a single type will be used in any given installation in order to simplify the installation procedure. It will also be noted that the vertical or plan view of  FIG. 6  shows an end view of the corrugations or flutes of the panel(s)  18 , i.e., ninety degrees to the panel orientation shown in  FIGS. 1 through 5 . This is intentional in order to show the different orientations that may be used with the present panel system  10 . The flute or corrugation orientation is not part of the present invention.  
      The lateral edge fastener  64  shown in the lower portion of  FIG. 6  is a double-ended externally threaded fastener, with the permanently installed portion  66  having a tapered thread formed thereon (i.e., wood screw configuration) and the opposite portion  68  extending outwardly from the edge trim or structure E having a constant diameter threaded shank, i.e., machine screw configuration. This type of fastener is conventional, and is known by the trade name “Tapcon”. The fastener  64  is permanently installed in the structure, and preformed holes or passages  70  (shown more clearly in  FIGS. 2 and 3 ) formed through the panel  18   a ,  18   b  adjacent the parallel lateral outboard edges  72   a  and  72   b  thereof (or edges  72 , for the single panel  18  as shown in  FIG. 3 ) are passed over the outwardly extending machine screw portions  68  of the fasteners  64  and secured using a suitable internally threaded fastener, e.g., wing nuts  48   b , etc.  
      It will be seen that the lateral edges  72  (or  72   a ,  72   b ) of the panel must be lifted outwardly to provide clearance over the protruding outer portions  68  of the fasteners  64  during installation, as shown in the installation method of  FIG. 2 . However, such permanently installed protruding lateral edge fasteners  64  are quite suitable for securing the lateral edges  72 ,  72   a , or  72   b  of the panels when the panel lower edge fasteners  40  have been first placed within the lower track  12 , rather than first being permanently installed through the panel lower edge attachment holes  44  of the panel(s).  
      The upper portion of  FIG. 6  illustrates an alternative lateral or outboard edge fastening system comprising flush-mounted internally threaded anchors  74  and machine threaded bolts or screws  76 , as shown more generally along the right edge of the panel  18   b  of  FIG. 1 . The internally threaded anchors  74 , e.g., expansion lugs or anchors, etc., may be used in masonry or other materials as desired. This type of installation is well-suited when the panel(s)  18 ,  18   a ,  18   b , etc. is/are to be installed according to  FIG. 3 , i.e., slid onto or into the two tracks  12  and  16  simultaneously, where the panel(s) cannot be pulled outwardly from the wall structure to any great degree to clear the protruding threaded studs  68 . In this instance, the panels are positioned with their lateral edge holes  70  aligned with the underlying flush anchors  74 , and machine bolts or screws  76  are installed through the panel edge holes  70  and into the anchors  74 . While the bolt or screw  76  illustrated in  FIG. 6  is shown with a slotted head requiring a screwdriver or the like, it will be seen that a conventional winged head may be provided for the edge bolt in order to obviate any requirement for tools to secure the lateral edges of the panel(s).  
      The panel attachment system  10  provides for more than a single panel to be installed over or across a given opening in a structure. Where the opening is wider or larger than the span of a single panel, plural panels may be temporarily joined together by means of an elongate panel connector strip.  FIG. 7  provides a detailed plan view of such a panel connector installation. In  FIG. 7 , first and second panels  18   a  and  18   b  are joined together at their adjacent panel connector edges, respectively  78   a  and  78   b , opposite their lateral or outboard edges  72   a  and  72   b  (shown in  FIGS. 1 and 2 ) by a panel connector  80 . As in the case of other panels  18 ,  18   a , and  18   b  shown in other drawing Figs., the first and second panels  18   a  and  18   b  are preferably formed of corrugated polypropylene plastic material, but other suitable sheet materials may be used. While only two joined panels  18   a  and  18   b  are illustrated in  FIGS. 1, 2 , and  7 , it will be seen that any practicable number of panels  18  may be joined by a series of panel connectors  80 .  
      The elongate panel connector  80  has a generally “H” shaped cross section, with an outer or first flange  82 , an opposite inner or second flange  84  substantially parallel to the first flange  82 , and an intermediate web  86  joining the two flanges  82  and  84  to one another and spacing them apart from one another. The two flanges  82 ,  84  and their intermediate web  86  define opposite first and second panel connector edge retaining channels therein, respectively first channel  88  and second channel  90 . The two channels  88  and  90  are coplanar with one another due to the flat configuration of the two flanges  82  and  84 . The panel connector edge  78   a  of the first panel  18   a  is placed within the first channel  88  of the panel connector  80 , with the panel connector edge  78   b  of the second or last panel  18   b  being placed within the corresponding second channel  90  of the panel connector.  
      While not a requirement, it is preferred that means be provided for permanently securing the panel connector  80  to one of the panel connector edges  78   a  or  78   b  of the corresponding panels  18   a  and  18   b , while providing for the removable installation of the opposite panel connector edge to the panel connector  80 . This simplifies the assembly of multiple panels to one another, as the panel connector strip  80  remains permanently attached to one of the panels. This may be accomplished as shown in  FIG. 7 , by forming an inwardly directed bead or lip  92  along one edge of one of the flanges, e.g., the second channel edge of the second flange  84 , as shown in  FIG. 7 . This inwardly directed bead  92  defines a gap or space between it and the inner surface of the opposite flange  82 , which is narrower than the thickness of the panel  18   b  inserted within the channel  90 . Accordingly, the panel  18   b  is deformed somewhat adjacent to its panel connector edge  78   b  as the bead or lip  92  grips the panel, thereby permanently attaching the connector strip  80  to the panel  18   b.    
      In conclusion, the panel attachment system in its various embodiments greatly facilitates the installation and removal of protective panels over structural openings and the like. The opposite tracks to which the panels are secured need only be installed once to the edges of the opening, with the panel itself or panels themselves being quickly and easily installed and removed from the tracks. The preferred corrugated polypropylene panels are quite light in comparison to conventional panels of plywood and similar heavy materials, and are thus much easier to manipulate, install, and remove. The translucence of the panels provides additional advantages in extreme weather conditions, when loss of electrical power and lighting is likely. Accordingly, the panel attachment system will enable users to install such protective panels much more quickly than is the case with conventional panels and systems.  
      It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.