Abstract:
A trackless roll-up door covering to contain materials within, and prevent animals from entering, a building or enclosure having a large door opening. In one embodiment of the invention an open weave vinyl coated polyester moisture resistant quick drying fabric material is fixedly weighted at a first end and fixedly attached to a tubular assembly at a second end. The tubular assembly is rotated by rotatable drive member, such as a motor, hand crank, spring loaded mechanism, which extends the fabric when operated in a first direction and retracts the fabric when operated in a second direction. Strapping members are used to secure the fabric material when it is extended to loosely close cover the door opening. Additional strapping members are optionally used to further secure the fabric material and prevent bowing in the center of the extended material.

Description:
FIELD OF INVENTION 
     The present invention relates to door opening closures. More particularly, this invention relates to a flexible covering apparatus for large door openings. 
     BACKGROUND OF INVENTION 
     Large door openings pose special problems in allowing entry of industrial equipment, such as, trucks, front loader, etc. while preventing the unwanted entry of animals such as birds, deer, etc. For example, road-side buildings housing materials, such as road salt used to de-ice roads, have large openings that lack doors to allow the entry of loaders and trucks to store or extract salt. Such door openings span over twenty feet in width and up to thirty feet in height and provide an adequate area for birds to enter and accumulate in the rafters therein. As is known, the collection of birds in these buildings, and pigeon lofts, and barns, etc, creates conditions that cause serious diseases, such as histoplamosis, in workers in the buildings. This is particular true when the buildings are not used for long periods of time and a large number of birds or other animals have taking up residence therein. 
     One method of closing these large door openings is by using a standard double hinged door. In this case, typically two doors can be swung open or closed on hinges attached to the sides of the door opening. This method has disadvantages as the door size makes the doors heavy and require a large amount of space to allow the doors to swing freely. In one case, when the doors are swung into the enclosure or building, the area to allow the door to swing open must remain clear. Hence, the door swing occupies valuable space that cannot be used to store materials. In the alternative, if the doors swing outwardly, then in cases of large snowfalls, a significant effort is necessary to clear an area to allow the doors to swing open. 
     A second method of closing these door openings is by using an overhead door that moves upwardly and is stored near the building ceiling. This type of door is advantageous as no space is lost for accommodating a door swing. However, an overhead door also has disadvantages, as it is extremely large, heavy and requires a track system to guide it into an open or close position. The heavy weight of the overhead door further creates additional problems in physically moving the door upward and downward. In one aspect, the weight of the door requires a significantly large motor to move the door up and down. In another aspect, the size and weight of the door represents a potential safety hazard as the moving door can cause significant injury to personnel caught in the path of a closing door. Hence, a sophisticated control system is needed to prevent a closing door from causing damage or injury. Further still, the tracks used to guide the overhead door into place are susceptible to damage by trucks or equipment operating within the building. For example, damage may occur to the track by a truck contacting a track guide. The track guide can then become mis-aligned or crimped, which can cause the overhead door to not close properly or even become disengaged from the track guide system. 
     An alternative type of door covering is a roll-up door, which rolls up onto a large roller suspended above the door opening. Roll-up doors typically are fabricated from a plurality of thin metal sheets, such as aluminum, steel, etc., which are hinged together to hang from a large overhead roller. The hinged metal provides flexibility for the metal sheets to collect around the suspended roller. However, while these roll-up type doors may be lighter than an overhead door, as discussed previously, the problem associated with damage to the track guides can also render these doors unfit for proper operation. 
     Accordingly, there is a need to provide a lightweight covering for a large door opening that allows the entry and exit of large vehicles and prevents the unwanted entry of birds, deer etc., without using a tracking guide system. 
     SUMMARY OF INVENTION 
     A trackless, lightweight, flexible door opening covering is disclosed. The flexible door opening covering rolls up and down on a roller mechanism which is rotatably driven by a motor mechanism, a spring loaded mechanism, a hand crank, etc. The flexible door covering is composed of a lightweight material is weighted at one end to allow the fabric to remain substantially taut as it is rolled up onto, or drawn from, the roller mechanism. Gravitation force on the weighted fabric end substantially guides the extending fabric vertically as it is drawn from the roller mechanism. In a preferred embodiment, the lightweight fabric is composed of a high-tensile strength open-weave vinyl material having finished edges. The material prevents animals from entering a building, when it is extended in front of a building opening, while allowing air circulation through the building. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     The advantages and aspects of the present invention will be more fully understood in conjunction with the following detailed description and accompanying drawings, wherein: 
     FIG. 1 a  illustrates a frontal view of a large door opening in an industrial enclosure or building depicting an exemplary embodiment of the invention; 
     FIG. 1 b  illustrates a side view of a large door opening in an industrial enclosure or building depicting an exemplary embodiment of the invention; 
     FIG. 2 illustrates a prospective view of an exemplary embodiment of the invention; 
     FIG. 3 illustrates a frontal view of the exemplary embodiment of the invention depicted in FIG. 2; and 
     FIG. 4 illustrates a cross-sectional view of the exemplary embodiment of the invention depicted in FIG.  3  through section A—A. 
    
    
     It is to be understood that these drawings are solely for purposes of illustrating the concepts of the invention and are not intended as a definition of the limits of the invention. It will be appreciated that the same reference numerals, possibly supplemented with reference characters where appropriate, have been used throughout to identify corresponding parts. 
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1 a  and  1   b  collective illustrate an exemplary enclosure  100  having flooring  110 , which is visible through opening  120 . Enclosure  100  may be used to store materials or vehicles, in preparation for their use at a later time. Further, illustrated is an exemplary roll-up covering  130 , constructed in accordance with the principles of the invention, suspended beneath roller cover  135 , which laterally spans opening  120 . In an alternate embodiment, roll-up covering  130  is larger in size than opening  120 , for example, by eight inches, and consequently extends beyond opening  120 . 
     In the illustrated example, covering  130  is shown as partially closing opening  120 . As would be appreciated, roll-up covering  130  can be drawn upward to fully expose opening  120  or extended downward to fully cover opening  120 . In the fully extended position, roll-up covering  130  prevents animals, such as deer, skunks, raccoons, birds, pigeons, etc., from entering building  100 , and taking up residence therein. 
     FIG. 2 illustrates a detailed prospective view of the roll-up opening cover  130  illustrated in FIGS. 1 a  and  1   b , without roller cover  135 . Fabric  140 , which is representative of the material covering opening  120 , is suspended from tubular bar  150 , which would be covered by roller cover  135  (see FIG. 1 a  and  1   b  ). Tubular bar  150  is supported by and held between a left support bracket  152 , and a right support bracket  154 , which are attached to respective ends of torsion bar  155 . Torsion bar  155  is fixedly to a wall or overhang using left mounting brackets  160  and right mounting bracket  162 , and, optionally, by at least one center bracket  164  spaced at a known interval. As shown, left mounting bracket  160  is representative of a wall mounting bracket that is typically attached to a vertical surface. On the other hand, right mounting bracket  162 , is representative of a soffit mounting bracket, which is typically attached to a horizontal surface. As would be appreciated by those skilled in the art, the use of wall bracket, i.e., left bracket  160 , or soffit mount bracket, i.e., right bracket  162 , and optional center bracket  164 , depends upon the desired mounting configuration. The number and placement of center brackets, as would be appreciated, depends upon the span of opening  120  and the width of torsion bar  155 . In a preferred embodiment, brackets are spaced at two foot intervals. 
     In one embodiment of the invention, attached at each end of tubular bar  150  are support brackets  152 ,  154 , which retain tubular bar  150  therebetween. Tubular bar  150  is rotatably coupled to support brackets  152 ,  154  to allow it to freely rotate. In an alternative embodiment support brackets  152 ,  154  can be attached directed to a mounting surface, for example, a vertical surface on enclosure  100 . 
     Within tubular bar  150  is optionally included motor  170 , as illustrated in the enlarged insert drawing of a left end of tubular bar  150 . Motor  170  is used to rotate tubular bar  150  such that when motor  170  is rotated in a first direction fabric  140  is drawn around tubular bar  150 , i.e., fabric  140  is raised. On the other hand, when motor  170  is rotated in a second direction, fabric  140  is extended from tubular bar  150 , consequentially lowering fabric  140  in front of opening  120 . Fabric  140  is thus raised and lowered into position without requiring a tracking guide system. Alternatively, hand-crank  171  can be used to raise and lower fabric  140 , when motor  170  is unavailable or inoperable. Furthers still, a spring-loaded mechanism (not shown) may be used to raise and lower fabric  140 . 
     Illustrated further is weight bar  190  extending laterally through one end of fabric  140 . Weight bat  190  provides a load within fabric  140  which holds fabric  140  substantially taut as fabric  140  is raised and lowered. Optionally, second weight bar  195 , extending laterally through fabric  140  is vertically spaced from weight bar  190 . Second weight bar  195  further includes at each end, at least one attachment means, illustrated as loop  200   a ,  200   b , respectively. Attachment means  200   a ,  200   b  can include hooks, eye-hooks, loops, latches, etc. In a second embodiment (not shown), attachments means  200   a ,  200   b , can be attached directly to fabric  140 , independent of the presence of second weight bar  195 . Attachment means.  200   a ,  200   b  can be attached to fabric  140 , for example, by crimping fabric  140  between extensions on attachment means  200   a ,  200   b  by pressure, fittings, screws, etc. 
     Fastening straps  210   a ,  210   b  may then be used to secure fabric  140  by attachment means  200   a ,  200   b , respectively, and attachment means (not shown), which are secured to the surrounding area. Fastening straps  210   a ,  210   b , can be selected, for example, as string, cord, rope, wire, springs, springs and strap combination, etc. In one embodiment of the invention, fastening straps  210   a ,  210   b  are bungee cords. This combination provides a flexible means to accommodate different distances between attachment means  210   a  and  220   a , and attachment means (not shown), which are secured to the surrounding area. In one aspect of the invention, fastenings straps  210   a ,  210   b  are composed of a combination of straps and springs. This combination also provides flexibility to accommodate different distances between attachment means. 
     Further, illustrated are leashing means  240   a ,  240   b . Leashing means  240   a ,  240   b  are attached to attachment points  241   a ,  241   b  at a first end, respectively, and removably attached to attachment points  242   b ,  242   a , respectively, at a second end. Attachment points  241   a ,  241   b ,  242   a .  242   b  are fixedly attached to building  100 . In this illustrative example, leashing means  240   a ,  240   b  are diagonally positioned across fabric  140  such that a second end of leashing means  240   a  is attached to attachment point  242   a  and a second end of leashing means  240   b  is attached to attachment  242   b . In this position, leashing means  240   a ,  240   b  provide additional support in securing fabric  140  by limiting perpendicular movement of fabric  140 . In an alternate embodiment, strapping means  240   a  is attached to attachment point  241   a  at a first end and operable to be laterally position across fabric  140  to engage attachment point  241   b  at a second end. Similarly, strapping means  240   b  is attached to attachment point  242   a  at a first end and operable to be laterally positioned across fabric  140  to engage attachment point  242   b  at a second end. 
     FIG. 3 depicts a frontal view of fabric  140  illustrating a preferred open-weave meshed pattern of fabric  140 . In this illustrative example, fabric  140  is formed from a high tensile strength, high tear strength vinyl coated polyester, which is moisture resistant and quick drying. Vinyl coated polyester suitable for use as fabric  140  has a weight in the range of 8-30 ounces per square yard. In a preferred embodiment, fabric  140  has a weight of 12 ounces per square yard. Open weave fabric  140  similarly may be specified by the number of vertical and horizontal threads per square inch. In such a specification, fabric  140  may have a range of 4×4 threads per square inch to 40×40 threads per square inch. 
     Also illustrated is attachment means  220   a , which is fixedly attached to a surrounding area. Attachment means  220   a  may be a hook, eye-hook, latch, etc., which is embedded in the Earth, a concrete block, etc., within a known distance from fabric  140 . Illustrated further, is fastening strap  210   a  securing fabric  140  by joining attachment means  200   a  with attachment means  220   a . As would be appreciated, fastening strap  210   b , similarly joins attachment means  200   b  to attachment means  220   b  (not shown). 
     FIG. 4 represents a cross-sectional view of an exemplary attachment of the present invention to a vertical mounting surface. In this exemplary assembly, support bracket  162  is representative of a wall mounted bracket, which is fixedly attached to vertical surface  102  of building  100 . Torsion bar  155  is removably attached to support bracket  162 . As shown in FIG. 2, a plurality of brackets, i.e., left mounting bracket  160 , right mounting bracket  162  and at least one center mounting bracket  164 , provide rigid support along the length of torsion bar  155 . Support bracket  154  is illustrated as extending outwardly from, and attaching to, one end of torsion bar  155 . Support bracket  154  provides support for tubular bar  150  as tubular bar  150  spans opening  120 . Further, tubular bar  150  is rotatably coupled to support bracket  154 . Tubular  150  is thus able to rotate between support brackets  154  and  152  (not shown) to raise or lower fabric  140 . 
     Fabric  140 , in one embodiment of the invention, is attached to tubular bar  150  by first creating a sleeve  405  in a first end fabric  140  and capturing sleeve  405  in slot  153 , which traverses tubular bar  150 . Sleeve  405  can be created by wrapping a first end of fabric  140  onto itself and applying an adhesive, such as an epoxy to fixedly attach fabric  140  first end. To further secure fabric  140  to tube  150 , bar  151  can be slide laterally through captured sleeve  405  to secure fabric  140  within tubular bar  150 . In an second embodiment of the invention, fabric  140  may be fixedly attached directly to tubular bar  150  using an adhesive, such as an epoxy. 
     Weight bar  190 , attached to a second end of fabric  140 , is used to render fabric  140  substantially taut, as fabric  140  is raised onto, or lowered from, tubular bar  150 . Optionally, second weight bar  195 , vertically disposed from weight bar  190 , may be used to contribute to, or distribute the, weight necessary to retain fabric  140  substantially taut. In this illustrative embodiment, first weight bar  190  and second weight bar  195  are contained within sleeves created by folding fabric  140  onto itself to create sleeves into which the illustrated weigh bars are contained. Weight bar  190 ,  195  may be of a metal construction, such as stainless steel, zinc, tin, etc. Although illustrated as two separate weights, it would understood that first weight bar  190  and second weight bar  195  may be fixedly joined a known distance apart. In such an embodiment, the combined weight bars provide a semi-solid lower edge to retain the contents of the enclosure therein. Alternatively, first weight bar  190  and second weight bar  195  can be a single solid material. In such an embodiment, the solid material provides a solid lower edge to retain the contents within the enclosure. Optional roller guide  440  shown attached to vertical surface  102  of building  100  retains fabric  140  a known distance from vertical surface  102 . 
     Although the invention has been described and pictured in a preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form, has been made only by way of example, and that numerous changes in the details of construction and combination and arrangement of parts may be made without departing from the spirit and scope of the invention as hereinafter claimed. It is intended that the patent shall cover by suitable expression in the appended claims, those features of patentable novelty exist in the invention disclosed.