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BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to de-mountable sunshade canopy structures and in particular sunshade canopies for ultraviolet (UV) sun ray protection of childrens&#39; play areas.  
           [0002]    It is increasingly acknowledged that physically challenging outdoor play structures are of benefit to the physical and emotional development of young children. A code of safety specifications for the construction and maintenance of childrens&#39; play structures has been developed by National Play and Playground Authorities, published (1996) by the National Recreation and Park Association Arlington, Va. These construction specifications describe construction features for support of childrens&#39; slides, swings, climbing apparatus, etc. which minimize risk of injury to children engaged in all manner of predictable use and misuse of the play structures.  
           [0003]    The specifications require that the play structures be mounted on a platform or on towers elevated up to six feet above a resilient (non-hardened) surface such as cork or rubber panels, and the towers or platform be supported by a very limited number of support columns. The columns are to be capped at the top and without exterior fittings on which a child could be caught or injured while climbing upon or falling from the platform or tower. The support columns are capped at the top to discourage a child from climbing or holding on suspended from the column top. The vertical support columns have been in the past a source of injures to children engaged in unintended use of these structures. Accordingly, the minimum number of vertical support columns, all free of hand or foot holds, has become a specification for acceptable safe design.  
           [0004]    Separate from the safe construction design specifications referred to above which have and are significantly reducing playground injuries there is a growing theat to childrens&#39; health when they are engaged in outdoor play and exercise in the sun shine.  
           [0005]    The earth&#39;s protective atmosphere ozone layer has been significantly depleted due to release of chemical pollutants into the atmosphere during the last five decades. The result of the ozone depletion is that the solar ultraviolet (UV) rays are significantly more intense and comprise a serious health risk to children without protection when playing in the now unfiltered UV sun radiation.  
           [0006]    In 1930 the risk of developing melanoma from sun exposure was 1 in 1500 people. Today a person&#39;s risk of developing skin cancer at some time during their life as a result of UV exposure is 1 in 75 people. Skin cancer is the most common cancer in the United States, with more than one million new cases diagnosed each year. Currently this year 47,700 Americans will be diagnosed with life threatening melanoma and 7,700 will die of the disease. The current prognosis for this disease is that approximately 1 out of 5 children in the United States will experience some form of skin cancer during their lifetime. Furthermore, exposure to the current intensity of solar UV radiation reduces the effectiveness of the immune system. This effect is of special importance in children&#39;s health.  
           [0007]    Sources of the above statistics are to be found in publications of the American Academy of Dermatology, American Cancer Society, National Institutes of Health, U.S. Center for Disease Control and Protection and the Australian Cancer Society.  
         OBJECTS OF THE INVENTION  
         [0008]    It is a first object of our invention to provide a sturdy, wind resistant, demountable canopy structure suitable for shading a childrens&#39; play area from direct rays of the sun.  
           [0009]    Another object of our invention is to provide a sturdy, wind resistant, demountable sun shade canopy for mounting on vertical support columns as used in childrens&#39; standard safe outdoor play structures. The sun shade canopy structure as described herein, is in full compliance with recommended safety specifications for childrens&#39; play areas.  
           [0010]    Still another object of our invention is to provide a sturdy, wind resistant, demountable sun shade canopy design adaptable to retrofit existing small area and extended childrens&#39; play area installations with effective sun shade protection.  
           [0011]    These and other objects and advantages and diverse uses of our invention will be apparent from consideration of the following illustrations, specifications and claims.  
         BRIEF SUMMARY OF THE INVENTION  
         [0012]    A demountable, wind resistant sun shade canopy suitable for mounting on a limited number of vertical columns, erected for the purpose of, or suitable for mounting on, extensions of a limited number of standard safe play area support columns. The canopy support structure, comprised of a plurality of uniquely shaped brackets which, when each is fixedly mounted, respectively, to the top of a vertical column, provides at each column a mount for a cantilever extending outward toward the perimeter of the area to be shaded, and simultaneously provides for mount of a hip beam extending toward the inner portion of the area to be shaded. Thus an extended-area rigid support structure is provided over a designated area which may be dependably shaded from the sun rays when a high density knitted polyethylene porous canopy cover is placed over the unique bracket supported plurality of cantilever and hip beam support members and secured about the perimeter of the canopy cover with an adjustable tension means. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of a portion of an existing safe play structure without sun protection; the play structure is shown mounted above a resilient ground cover.  
         [0014]    [0014]FIG. 2 is a cross section of the upper portion of a support column taken along the plane  2 - 2 .  
         [0015]    [0015]FIG. 3 is a plane view of a specified safe design single tower childrens&#39; play area on which our innovative sun shade canopy has been erected; the play and exercise devices are shown in phantom lines.  
         [0016]    [0016]FIG. 4 is a sectional elevation view of the embodiment of our invention shown in FIG. 3 with portions of the play structures and canopy support members shown in phantom.  
         [0017]    [0017]FIG. 5 is a perspective view of a construction bracket for mounting cantilever beam and hip beam members to form a support structure for mounting the canopy cover.  
         [0018]    [0018]FIG. 6 is a cross section of the construction bracket shown in FIG. 5 taken on the plane  6 - 6 .  
         [0019]    [0019]FIG. 7 is a plane view of the connector for the four hip beam canopy support members shown in the embodiment of our sun shade canopy illustrated in FIGS. 3 and 4.  
         [0020]    [0020]FIG. 8 is a perspective view of the hip beam connector illustrated in FIG. 7.  
         [0021]    [0021]FIG. 9 shows detail of means for fastening the canopy cover to the support structure with adjustable tension means.  
         [0022]    [0022]FIG. 10 shows a section of an extended end of the cantilever member showing means for securing the canopy cover.  
         [0023]    [0023]FIG. 11 is an elevation view of a second embodiment of our sun shade canopy structure mounted to cover a two tower specified safe children&#39;s play area.  
         [0024]    [0024]FIG. 12 is a plane view of the embodiment of our sun shade canopy shown in the embodiment illustrated in FIG. 11. The children&#39;s play area devices are shown in phantom. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0025]    A safe design childrens&#39; play structure is illustrated in FIG. 1 wherein a plurality of fixedly mounted vertical columns  12   a ,  12   b ,  12   c  and  12   d  are shown. The columns  12   a ,  12   b  etc. are mounted in foundations (not shown) beneath a resilient ground cover  14 . The ground cover may be made of rubber or cork matted materials to soften impact and reduce injuries to a child falling thereon.  
         [0026]    The columns support a platform  16  from which a slide  18 , a closed chute  20  and other childrens&#39; climbing and exercise devices may be positioned.  
         [0027]    The upper end of conventionally designed vertical columns  12   a ,  12   b ,  12   c ,  12   d  is shown in FIG. 2 in cross section on plane  2 - 2 . A column cap  22  fits over the top of the column  12   d . The cap  22  is shaped with a reduced diameter lower section  24  which, when inserted into the hollow opening  26  of the vertical column, comprises a secure mount for the column cap. Although such conventionally designed columns are fully compatible with the invention, in order to avoid the possibility of rainwater leaking into the seam between lower portion  24  and column  12   d , it is preferable to have the columns designed as depicted in FIG. 6, where the upper end of column  12   a ,  12   b , etc. has a smaller diameter than bracket  52  so that rainwater will flow over the juncture between the two without entering the seam.  
         [0028]    [0028]FIGS. 1 and 2 are illustrative of safe childrens&#39; play structures in compliance with the safety specifications developed by the National Play and Playground Authorities, At this date there are tens of thousands of such play structures erected and being erected in the United States without provision for effective sun shade for children using such structures.  
         [0029]    A plan view of a first embodiment of our invention is shown in FIG. 3 wherein a canopy cover  30  is shown supported over structural members described below which in turn are mounted above a children&#39;s play structure area. Children&#39;s exercise and play devices are shown at  32  in phantom lines below the canopy  30 .  
         [0030]    A cross section elevation of the FIG. 3 embodiment is shown in FIG. 4 taken on plane  44 . Vertical columns  34  and  36  are fixedly mounted respectively in concrete foundation footings  40  and  42 . The vertical columns support a platform or deck  44 . The columns  34 , 36  terminate at approximately four feet above the platform or deck  44 . Caps  22  such as shown in FIG. 2 have been removed from the upper column portions  60 , 62  of the columns  34 ,  36  exposing the tops  48 ,  50  respectively, of columns  34  and  36 . Structural bracket fittings  55  and  57  have lower ends  56 ,  58 , which, fit over the tops  48 , 50  of columns  34  and  36 .  
         [0031]    [0031]FIGS. 5 and 6 are illustrative of the structural brackets fittings  55  and  57 ; more specifically, FIG. 5 depicts bracket  55  in a perspective cut-away fragmentary view while FIG. 6 is a view of the structural bracket  55  shown as a cross section on plane  6 - 6 . In preferred embodiments, the lower portion  56  of structural bracket  55  fits over the reduced diameter upper end  52  of the upper column portion  60 . In rainy weather, water will flow over the juncture of lower portion  56  and upper end  52  and will not enter the seam where it might cause damage.  
         [0032]    The upper end of the bracket is terminated with a transverse angularly mounted cylindrical rod  64 . The rod  64  is mounted at an acute angle with the vertical cylinder extension. The angle with the horizontal is normally 22 degrees, but is subject to adjustment as required for specific application.  
         [0033]    Mounted as shown in FIG. 5 and FIG. 6, the cylindrical rod  64  has an upper, or first end  68 , and a lower, or second  70 , end. Hip beam  72  comprises a straight section of a hollow metal steel pipe or rod. The hip beam  72  is positioned over the upper, or first end  68 , of the angle mounted cylindrical rod  64  and secured with threaded bolt means  76  passed through the hip beam  72  and the cylindrical rod  64 .  
         [0034]    The lower or second end  70  of the solid metal rod  64  is mounted over a cantilever beam  80  comprised of a straight section of hollow steel pipe at its upper end and secured with threaded means  81 . The lower end of the cantilever beam is terminated with an oblong eyelet connector  84 .  
         [0035]    As shown in fragment view in FIGS. 7 and 8 the four hip beams  72 , 74  and counter parts  72   a ,  74   a  terminate in juxtaposition and are secured together with a right angle joint  86 .  
         [0036]    Referring now to FIG. 3, a porous woven polyethylene canopy cover  30  is placed over the structure comprised of hip beam members  72 ,  72   a ,  74 ,  74   a , and cantilever beam members  80 ,  80   a ,  82 ,  82   a . The canopy details are more clearly shown in FIG. 9. The canopy cover  30  is secured about its perimeter with a tension cable  90  which is secured within a cable channel  92  sewn about the canopy perimeter  94 . The tension on the cable  90  is adjusted and maintained with a turnbuckle  96 . The canopy cover  30  is provided at its four corners with a reinforced opening  98  through which the oblong eyelet connector  84  located on the extreme end of the cantilever beam  80  and its counterpart cantilever beams  82 , etc. protrudes.  
         [0037]    A second embodiment of our invention is illustrated in FIGS. 11 and 12 wherein a two tower safe design children&#39;s play area is shown. The play and exercise devices are shown in phantom lines. A porous shade canopy  104  fabricated with woven polyethylene strips is constructed similarly to the single tower canopy cover  30 . The two tower canopy cover  104  is sewn so that it provides a cable channel  106 . A tension cable  108  is threaded through the channel  106  and when positioned over the metal support structure of hip beams  110   a ,  110   b ,  110   c , etc. ridge beam  112  and cantilever beams  114   a ,  114   b ,  114   c , etc. forms a sunshade canopy. A turnbuckle tension means  116  is attached to the ends of the cable  108  to provide adjustment and to maintain cable tension.  
         [0038]    The canopy cover  104  is provided at each corner with a reinforced opening  98  as shown in FIG. 9, through which the oblong eyelet connector  84  on the cantilever beam extends.  
         [0039]    The purposes and other advantages to our invention and possible application to sun sheltering purposes beyond those described in connection with children&#39;s play areas will be apparent from the following claims.

Summary:
A demountable, wind-resistant sun shade canopy for shading childrens&#39; play areas or other actively used areas. The canopy cover, being removably secured over a metal support structure, is comprised of vertical columns upon which are mounted at the upper end thereof respectively, uniquely configured bracket fittings, each bracket fitting providing secure mounting for a cantilever beam extending outwardly toward the perimeter of the area to be shaded, and providing secure mounting for a hip beam extending upward and toward the inner portion of the area to be shaded.