Abstract:
Pneumatic hurricane shutters are designed to temporarily cover a window or door in a building or other structure. The shutters have a lightweight rigid frame for surrounding the openings and mounting on fasteners attached to the building. Elongated pneumatic tubes are connected to frame rails and span the space between the rails to protect the opening. The frames can be locked in place to prevent inadvertent removal once in place. The frames and deflated tubes can be stored until the approach of a storm at which time the frames may be attached to the building and the tubes inflated to protect the openings.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to temporary protective barriers used to protect buildings and their contents from the effects of high velocity winds and the associated debris. 
   2. Description of the Prior Art 
   As is known by one skilled in the art of protecting buildings and the like from damage caused by missile-like objects that are occasioned by heavy winds such as tornadoes and hurricanes, there are commercially available variations of hurricane protective devices, often called shutters, that fasten immediately over the frangible area to be protected. 
   Conventional hurricane shutters are typically expensive to purchase, cumbersome, made from stiff, heavy material such as steel and aircraft quality aluminum alloy or occasionally reinforced plastic. Many shutters need to be manually connected and then removed and stored at each threat of inclement weather. Many others require unsightly and difficult-to-mount reinforcing bars at multiple locations. Further, these known shutters are usually opaque, preventing light from entering a shuttered area and preventing an inhabitant from seeing out. Likewise, it is desirable that police be able to see into buildings to check for inhabitants and to prevent looting which can be a problem in such circumstances. Missiles, even small not potentially damaging missiles, striking these heretofore known shutters create a loud, often frightening noise that is disturbing to inhabitants being protected. 
   There are also a number of patents directed to the use of knitted or woven fabric such as netting, tarpaulins, drop cloths, blankets, sheets, wrapping and the like for anchoring down recreational vehicles. 
   Other protective coverings using an inflated barrier are known, as shown by Figge et al, U.S. Pat. No. 6,266,926 B1; Lightell, U.S. Pat. No. 4,255,907; Miller, U.S. Pat. No. 5,937,595; Nally, U.S. Pat. No. 3,911,630; and Bessler, U.S. Pat. No. 4,098,035. However, these devices lack a defined frame for maintaining the inflatable barrier in the proper orientation and for secure attachment to a building. 
   What is needed in the art is a lightweight, wind, rain and debris protective system, for individual openings, that can be stored in minimal space and quickly installed to protect openings in structures. 
   SUMMARY OF THE PRESENT INVENTION 
   The present pneumatic hurricane shutters are formed from a lightweight rigid frame for surrounding the openings in a building such as a doorway and window. Elongated pneumatic tubes are connected to the frame rails and span the space between the rails to protect the opening. The frames and deflated tubes can be stored until the approach of a storm at which time the frames may be attached to the building and the tubes inflated to protect the openings. 
   The frames are adapted to be securely and removably attached to a surface of a structure about an opening, usually bolts embedded in the structure. The frame includes at least two rails, one of the rails adapted to be disposed on one side of an opening and the other rail adapted to be disposed on an opposite side of the same opening. The frame includes a fastening means for attaching the frame to the structure to support a plurality of elongated pneumatic tubes extending across the frame and inflated to fill the space within the frame. 
   Therefore, an objective of this invention is to provide a hurricane shutter with an inflatable barrier supported by a frame attachable to a building. 
   It is another objective of this invention to provide a frame with fastening devices for cooperation with mounting devices located on the structure to removably fix the shutter on a structure covering an opening in the structure. A lock is included in the frame to prevent inadvertent removal of the shutter. 
   It is a further objective of this invention to provide an inflatable barrier connected to the frame to increase the resilience of the barrier. 
   It is a still further objective of this invention to provide a second set of fastening means on the inflatable barriers to cooperate with the frame and the mounting devices to fix the barrier in place. 
   It is yet another objective of the invention to provide a valve in the inflatable barrier for semi-rigid inflation and deflation for storage. 
   Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective of the pneumatic barrier of this invention in place on a building; 
       FIG. 2  is a cross section of an alternative assembly of the invention shown in  FIG. 1 ; 
       FIG. 3  is a cross section of another embodiment of the pneumatic barrier of this invention; 
       FIG. 4  is a cross section of another embodiment of the invention shown in  FIG. 1 ; and 
       FIG. 5  is a perspective of a one-way valve of this invention; 
       FIG. 6  is a cross section of an alternative assembly of the invention shown in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The pneumatic hurricane shutter  10  has a frame  11  fabricated to fit conventional windows and doors in commercial or residential buildings and pre-fabricated mobile structures. The frame rails  11   a,    11   b,    11   c,  and  11   d  surround and fix in place a pneumatic barrier  12  composed of a plurality of pneumatic pillows  28 . The hurricane shutter may be deployed with frame rails on all sides of the opening or the frame members may only be used on opposite sides of the opening. 
   Of course, the pneumatic shutters  10  of this invention may be used with flush mounted windows and doors or exterior recessed windows and doors in which case the pneumatic barriers would be placed within the window or door sill and the frame would be flush with the exterior of the building. The top flange  11   b  extends transversely across the opening between the top of the window and the roof of the building. All of the frame members have key hole slots  14  extending through the members. Each of the key hole slots has a narrow retainer section  16  and a larger mounting section  17 . The mounting section  17  is of a size to accommodate the head of a bolt or pin attached to the building. 
   The pneumatic shutter member  12  has a reinforced tunnel hem  13   a,    13   b,    13   c  and  13   d  on each edge. Each of the hem sections have a series of key holed shaped apertures  15  spaced along the length of the hem. The spacing of the apertures  15  and the key hole slots  14  are such that the apertures and the slots will register with each other. 
   The registered apertures and slots are then placed over a spaced series of bolts (not shown) anchored in the building about the openings. Once all the bolt heads are placed in the registered apertures and slots, the frame  11  can be lowered to engage the retainer section  16  about the bolt shaft to fasten the frame  10  to the building. The bolts may then be tightened to secure the shutters in place. In the event the bolts are not tightened for any reason, there is a locking means to secure the shaft of the bolts in the retainer section of the key hole slots and apertures. After the bolts and slots are registered, a hole through the barrier and the frame registers with a pin or hole in the building. Insertion of the pin through the hole  20  will prevent the key hole slots and apertures from dislodging from the bolts. Alternatively, a bolt may be screwed through the hole  20  to secure the shutter in place. 
   The reinforcing bar  41  may be added to the shutters  10  for additional strength and security. The rigid bar has the same shaped slots as the frame members and are to be placed over the shaft of a bolt or pin extending through the shutter. 
   The vertical frame members  11   b  and  11   d  are shown, in  FIG. 2 , as deployed on the outside of the tunnel hem  13   a  and  13   c,  as a matter of choice. The frame members may be positioned between the building and the pneumatic shutter or as the outer component of the system. Also shown, in  FIG. 2 , is an embodiment of the pneumatic shutter  10  in which the pneumatic pillows  28  are semi-circular with a planar backing. 
   In  FIG. 3 , the pneumatic barrier  12  has a compound series of pillows  28 ,  28   a  with one set being semi-circular and oriented perpendicular to the other semi-circular set with the planar backing of each in contact with each other. This orientation provides more resilience and increases the space in which debris may be decelerated before contacting the frangible portion of the opening. The sets may be integrally made in one piece or they may be separate and added to each other, as needed. Other angular orientations may also be used between the sets. Slots  14  and registered apertures  15 , between a frame member telescoped within a hem, are also shown. In  FIG. 4 , another modification of the pillows  28  is depicted. In this embodiment, the pillows  28  are formed as circular tubes. 
   The pneumatic barrier  12  is attached to the frame  11  which provides the structural support for the pneumatic barriers, both in the storage condition and when inflated and mounted on a building. This allows each shutter to be easily handled as a discrete unit with mounting requiring only matching the key hole slots with the bolts in the building. The frames and the deflated pneumatic pillows may be stored in minimal space. Once the frames are in place, the pneumatic barriers can be inflated for protection. 
   The pneumatic barrier pillows  28 , as shown, are composed of a series of inflatable tubes. The shape of the inflated portion of the pillows may have different designs, such as, octagonal, circular, zig-zag, etc. The tubes  28  are preferably connected with each other by a web  29  that combines the tubes into a unitary whole. The tubes and the web may be made from a multi-layered laminate with the web formed by sealing the multi-layered material together and the tubes being the non-sealed areas. A conduit can also be formed in the web connecting all the inflatable tubes, with the open end of the conduit having a one-way valve for inflation and deflation. The conduit may also include a pressure relief valve, well known in the art of pneumatic devices, for preventing over-pressurization of the barriers. The web  29  has margins extending beyond the tubes and forming the hems  13   a ,  13   b ,  13   c and  13   d . The margins can be connected to the frame  10  by bonding or other adhesive application. The material of the pneumatic barriers is preferably flexible but non-extensible to create a semi-rigid structure when inflated. Stiff polymers, such as KEVLAR, polypropylene, NYLON, or other laminates having a non-extensible layer, such as polyurethane films with intermediate lamina of woven mat, may be used along with any other material having the requisite properties. It is also desirable for the pneumatic barriers to be transparent or opaque. 
   The tubes  28  may have individual inflation valves  31 ,  32 ,  33  with the interior of each tube segregated from the other tubes. This provides an extra measure of safety since a puncture in one tube will not allow complete deflation of the pneumatic barrier  12 . As mentioned above, the tubes may be connected by a conduit for inflating all the tubes through a common inflation valve. 
   The valves  31 ,  32 , and  33  are one way valves which may be made of polymers. The valves, as shown in  FIG. 5 , have a flat valve body  34  bonded about an aperture in the pneumatic tube. The valve body has an inlet  35  connecting the interior of the tube with the atmosphere. A flap valve  36  closes the inlet  35  and is attached to the valve body forming a hinge  37 . The hinge  37  is biased flat or closed and the flap pivots into the interior of the tube so that inflation pressure will hold the valve closed. The valve may be opened by a probe to allow deflation, when desired. Other valve may be used, such as provided for inflatable footballs, soccer balls, basketballs, or tire valves. 
   It is of importance that the material affords sufficient impact protection to meet the regulatory agencies&#39; requirements in order for this to be a viable alternative to other hurricane protective mechanisms. While stiff structures, such as panels of metal, are easily tested for impact requirement and have certain defined standards, pneumatic barriers on the other hand, are flexible and react differently from stiff structures. Hence the testing thereof is not as easily quantified as the stiffer materials. However, certain empirical relationships exist so that correlation can be made to compare the two mediums. Typically, the current impact test of certain locales requires a wood 2×4 stud be shot at the barrier exerting a total force of approximately 230 pounds, or 61.3 pounds per square inch (psi), over its frontal (impacting) surface of 3.75 square inches. 
   The preferred embodiment of this invention would use a polymer tube having at least a burst pressure above the force exerted by the nominal 2×4 test missile. Without being held to the theory expressed here, the tubes respond somewhat akin to a hydraulic piston in that the 61.3 psi applied over a 3.75 square inch surface of the 2×4 (first piston) on the outside of the inflated tube is transferred to the total interior surface area of the tube (second piston) which is in contact with the window. For example, a standard window is approximately 2 feet wide and 3 feet high. The pneumatic tubes would be approximately 3 feet long. The diameter of the tubes is approximately 7 inches. The area in contact with the window, at impact, would be approximately 252 square inches which reduces the impact on the window to approximately 1 psi. The area at impact accounts for the compression of the air in the tubes and deformation of the tube against the window. Not only is the impact force reduced but the application of that force is spread evenly over the length and width of the tube. Obviously, the diameter of the pneumatic tubes would affect the transferred force and the diameter can be adjusted for different expected impacts. 
   The discretionary use of additional sets of barriers, as illustrated in  FIG. 6 , adds flexibility to the system in that the reduced force transferred by the tubes is further reduced and spread by the entire surface of the mattress. 
   A number of embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrated embodiment but only by the scope of the appended claims.