Patent Publication Number: US-8991413-B2

Title: Canopy tensioning apparatus

Description:
FIELD OF THE INVENTION 
     This application relates to building structures and more particularly to canopies having a fabric stretched over a framework, and still more particularly to a tensioning apparatus for maintaining the fabric in a stretched condition. 
     BACKGROUND OF THE INVENTION 
     Building structures such as fabric canopies are generally used as sunshades in playgrounds, parks and the like. To install and maintain fabric canopies, it is desirable that a tensioning apparatus be a part of the structure, and further, that the tensioning apparatus be easy to install and adjust, requiring no special tools or dismantling of the structure during adjustment. In the past, a come-along, i.e. a hand operated lever winch, has been used to tension the fabric. However, a come-along, in addition to being somewhat hard to use, is also obtrusive and unsightly. 
     It is therefore a benefit of the subject invention to have an adjustable and easily installed fabric canopy. 
     It is further benefit of the subject invention to have a tensioning apparatus for use with a fabric canopy. 
     A still further benefit of the subject invention is a tensioning apparatus that can be adjusted without special tools. 
     SUMMARY OF THE INVENTION 
     The subject invention, in one aspect, includes a tensioning apparatus for a fabric canopy that is supported on a vertical upright. The vertical upright is one of the supports for the fabric canopy. The tensioning apparatus includes a longitudinally movable hook that catches an eyelet, loop, or other opening in the fabric and can, by movement of the hook along the longitudinal axis of the tensioning apparatus, either tighten or loosen the tension of the fabric canopy as needed. The hook is located in an open longitudinal slot in the tensioning apparatus and extends to within the tensioning apparatus, being secured to a threaded nut on a threaded shaft. The threaded shaft is secured for rotation at either end so that upon rotation of the shaft, the hook moves longitudinally, for an adjustment of the tension of the fabric. 
     These, and other aspects of the subject invention can be better understood and appreciated in conjunction with the accompanying drawings. 
    
    
     
       CONCISE DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of the subject invention showing its use with a fabric canopy. 
         FIG. 2  is a perspective view of an embodiment of the subject invention with the interior shown in broken lines. 
         FIG. 3  is a side view of the embodiment of the subject invention of  FIG. 2  with the interior shown in broken lines. 
         FIG. 4  is a front view of the embodiment of the subject invention of  FIG. 2  with the interior shown in broken lines. 
         FIG. 5  is a perspective view of the embodiment of the subject invention of  FIG. 2  with the interior shown in broken lines. 
         FIG. 6  is a side view of the embodiment of the subject invention of  FIG. 2  with the interior shown in broken lines. 
         FIG. 7  is a cross sectional view of the embodiment of  FIG. 2  taken along the lines  7 - 7  of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF ONE EMBODIMENT OF THE INVENTION 
     With respect to  FIG. 1  there is shown a fabric canopy  10  utilizing the subject inventive cylindrical tensioning apparatus  15 . The fabric canopy is formed of a plurality of roof support beams  17  supported at one end by vertical support posts  12  and in the center by a center post (not shown). The tensioning apparatus is mounted on each vertical support post  12  ( FIG. 3 ), or possibly only selected vertical support posts, as necessary. Vertical support post may have a metal upper portion which can be welded or otherwise fixedly secured to tensioning apparatus  15  at opening  13  ( FIGS. 3 ,  5  and  6 ). The roof support beams  17  are mounted to the tensioning apparatus at an outward or distal end and to the canopy center post at the other end, to thereby support the canopy. The tensioning apparatus maintains the tautness of the fabric and helps keep it in a stretched condition. Any size and shape of canopy as well as any suitable fabric is intended for use with the subject invention. 
       FIG. 2  shows the subject invention, with the interior in phantom. An interior shaft  30  is mounted by internal mounting plates  36  and  38  at each end respectively, the mounting plates generally conforming to and fixed to the interior of the cylindrical housing  19  with the exception of an open area  37 ,  39  at one end ( FIG. 3 ). The mounting plates  36 ,  38  may thus take the shape of a round washer with a flat side  37 ,  39 . The flat side of both mounting plates is positioned to be on a side of the cylinder  19  opposite that of the hook  20 , to be described. Housing  19  is open at opposing ends  40  and  41 ; end  41  allows the connection and holding of a roof support beam  17 , while end  40  allows engagement by a tool (to be discussed) with shaft  30 . The roof support beam  17  is hollowed out at the outside or distal and to permit entry into opening  41  and permit engagement of the nut with a tool. 
     The interior shaft  30  is threaded at each end and at least through a portion of the center of the shaft. The shaft  30  may be threaded throughout its length, if desired. 
     The interior shaft has a hexagonal head  34  at an outside end and is secured in position by a nut, preferably, hexagonal, at a distal end outside mount  38 . Washers  35  may be used. The outside end of the shaft is secured by a nut or other fastener  32 . This nut  32  is held on the shaft so the nut rotates with the shaft does not loosen, and holds the shaft in place relative to housing  19 . 
     An elongated opening or slot  24 , best shown in  FIGS. 4 and 5  is shown formed in an outer portion of the apparatus housing  19 , through it may be located on any portion of the housing. Through slot  24  a hook  20  with a bent outer portion  28  emerges. Hook  20  has an inner portion  26  that tightly and fixedly engages a nut, such as a hexagonal nut  22 . Nut  22  is threadedly engaged with shaft  30  for travel along the shaft upon rotation of the shaft. The nut  22  need not be hexagonal, it can be any shape as long as it is fixed to the inner portion  26  of hook  20 , so that the nut  22  travels along shaft  20  when the shaft is rotated. 
     The bent outer portion  28  of hook  20  has its distal end pointing to the outer end of the housing  19 . Upon rotation of shaft  30 , nut  22  and thus hook  20  are caused to move longitudinally along the axis of shaft  30  when the shaft is rotated. 
     In another embodiment hook  20  may be simply a straight post which is long enough to make it difficult for the eyelet or loop with which it is engaged to disengage. 
     The head of the shaft may have a shape, such as a hexagon or square which permits engagement with a tool, such as a socket or wrench, to manually rotate the shaft. A slotted head, a Phillip&#39;s head or other screw drive may also be used with a complimentary shaft head. Thus, by rotating the shaft, the hook  20  will move in a direction dictated by the direction of rotation of the shaft as shown by the arrows in  FIG. 7 . 
     As stated, mounts  36  and  38  have one flat side, and are oriented so that the flat side is on the bottom of the cylinder, opposite the hook, leaving an opening or passageway within the cylinder  19  for water to drain out. 
     In the use of the subject invention, the canopy is set up in the normal fashion, with a center vertical support post, which is connected to and supports roof support beams  17 . Roof support beams are supported at an outer end with vertical support posts  12 , which have the tensioning apparatus  15  secured at an upper end and supporting the distal end of the roof support beams  17 . The fabric for the canopy is spread over the roof support beams, there are spaced, equidistant loops or eyelets at the periphery of the fabric, and the loops engage the hooks, which may then be moved in or out along the longitudinal axis of the tensioning apparatus  15  by rotating the shaft head  34 . This action rotates the shaft  30  which moves the hook accordingly. When all loops are engaged with the respective hooks, it is a matter of tightening and loosening each canopy section as necessary through appropriate rotation of the shaft head  34  to achieve the right tensioning and placement of the canopy fabric. 
     It will be understood that the foregoing description is of preferred exemplary embodiments of the invention and that the invention is not limited to the specific forms shown or described herein. Various modifications may be made in the design, arrangement, and type of elements disclosed herein, as well as the steps of making and using the invention without departing from the scope of the invention as expressed in the appended claims.