You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to window shades and awnings. 
         [0003]    2. Description of Prior Art 
         [0004]    Awnings for interior and exterior use are well known to the art. They usually consist of a fabric main panel which is draped from a top member, usually a rod or bar, which is connected to the wall or window frame. The bottom of the draped main panel is held away from the supporting structure with a “U” shaped frame, which is attached to the supporting structure at its two frame ends, and the frame is approximately parallel with the ground, at all points. The points of attachment at the frame ends may be hinged to allow the awning to be swung upward for storage. The awnings may have side panels, which are usually integral to the main front panel. The “U” shaped frame may consist of several connected parts or be integral to the front and/or side panels, where those panels are ridged. While the attachment of the frame ends to the supporting structure, usually a wall or window frame, makes the awning suitable for windy conditions it prevents the easy removal and erection of the awning. It also introduces unnecessary hardware and on removal results in unsightly hardware or damage to the supporting structure. 
         [0005]    Prior art awnings are attached to the supporting structure at the ends of the “U” shaped frame, and/or along the interface between the side panels and the supporting structure, which makes them difficult and time consuming to remove. 
         [0006]    Prior art awnings do not have means of removing the awning without leaving unsightly hardware attached to the supporting structure, or holes where the hardware has been removed. 
         [0007]    What is needed is an awning design which renders unnecessary the said attachment between the ends of the “U” shaped frame and the supporting structure. 
         [0008]    What is needed is a method of easy and quick erection and removal of the awing or window shade. 
       SUMMARY OF THE INVENTION 
       [0009]    The preferred embodiment of the invention is an awning or sun shade which has no attachment between the frame ends  4   b  of the “U” shaped frame  4  or along the interface between the side panels  2   a  and the supporting structure  3   a . The shape and fixed position of the awning or shade is maintained solely by the detachable attachments at the top of the main panel  2  and the moment of force  7 , exerted by gravity, having its centre of motion along a line at the top of the main panel  2  coincident with the line of attachment of the awning  1  to the supporting structure  3   a . Such moment of force  7 , acting in the direction of the said supporting structure plane  3   a , and thus holding the said awning  1  snuggly against the said supporting structure  3   a.    
         [0010]    Another embodiment of the invention is the frameless or rod-less means of attaching the top of the main panel  2  to the supporting structure  3   a , such that the awning can be quickly erected and removed. Some preferred embodiments of the invention have a simple adhesive strip  6  attached to the top of the main panel  2 . This adhesive can be designed, by means well known to the art, for example, similar to that used in 3M Corp.&#39;s “Post-its™, so that the bond will hold the awning  1  in place, but which can be detached without damage to the exterior surface of the supporting structure  3   a.    
         [0011]    Other embodiments of the invention, having no top frame or rod, use complementary strips of loop and hook material, such as Velcro™ to detachably attach the top of the main panel  2  to the supporting structure  3   a .  FIG. 2  illustrates strip  6   a , which can be adhesive tape backed and which maintains adhesion to the supporting structure  3   a . The front surface is populated with either hooks or loops and which detachably attaches to the complementary loops or hooks of strip  6   b , which is in turn attached to the main panel  2  of the awning  1 . This permits the awning to be quickly removed for cleaning or be replaced with another awning of another color or opacity, as desired. The adhesive on the strip  6   a  can also be peelable at low energies, but higher than that between the said hook and loop bond, such that the strip itself can be removed without damaging the surface of the supporting structure  3   a . These strips  6 ,  6   a  and  6   b  are of varying stiffness as in some embodiments stiffer strips are used to establish a straight top panel edge and in those embodiments which include side panels, a straight side panel edge. In other embodiments more flexible strips  6 ,  6   a ,  6   b , are used to facilitate cleaning and storage. 
         [0012]    The preferred embodiment of the invention includes a ‘U” shaped frame  4 , which is threaded through a folded over and then stitched end of the main panel  2 , which forms an open ended sleeve  5 . Some embodiments of the invention have rigid main panels  4  and in these cases the “U” shaped frame will be integral to the main panel  4  and hence the awning  1 . 
         [0013]    Some embodiments of the invention have side panels  2   a , such as illustrated in  FIG. 1 , while others do not as illustrated in  FIG. 3 . Other embodiments of the invention have side strips  2   b  which grasp and prevent the frame ends  4   b  from slipping down the supporting structure  3   a.    
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a perspective view of a hanging awning  1 , shading window  3 , which is detachably attached to the supporting structure by only an adhesive strip  6 . 
           [0015]      FIG. 2  is a perspective, view of a hanging awning  1  which is detachably attached to the supporting structure  3   a  by means of complementary strips of loop and hook material, one  6   a  adhering to the supporting structure  3   a  and the other  6   b  being attached to the top of the main panel  2 . The two strips  6   a ,  6   b  interlocking, when pressed together. 
           [0016]      FIG. 3  is a perspective view of the awning  1  without side panels  2   a.    
           [0017]      FIG. 4  is a perspective view of a preferred embodiment which has no side panels  2   a , but supports the “U” shaped frame  4   a  ends by means of a hanging strip  2   b.    
           [0018]      FIG. 4   a  is a detail of  FIG. 4  illustrating the fold or cup  2   c  formed in the hanging strip  2   b  and which supports the frame end  4   a  of the “U” shaped frame  4 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]      FIG. 1  illustrates a hanging awning  1  which is detachably attached to the supporting structure  3   a  by means of an adhesive strip  6 . Said awning  1  is shading window  3 . In this embodiment of the invention the said adhesive strip is bonded to a top fold or end of the main panel  2 . A “U” shaped frame  4  is treaded through a fold  5  in the main panel  2  and the side panels  2   a . While the preferred embodiment has a “U” shaped frame  4 , it is to be understood that any suitable shape may be used and all such shapes are within the ambit of the invention. Similarly, the frame  4  may be connected to the awning  1  by all suitable means known to the art, such as loops, hook and loops connectors, snap connectors etc. In some embodiments of the invention the frame  4  may be flexible or springy, allowing the operator to bend the said frame  4 , for example, temporarily straightening it and allowing for easier threading and unthreading of the frame  4  into and out of the sleeve  5 . Similarly, the frame  4  may be an integral part of the main panel  2  and/or side panel  2   a , such as when one or more of those panels are rigid. It is to be understood that for the purposes of this disclosure that the frame  4  can be any shape retaining element or member or a part of any other element, which holds the main panel  4  off the surface of the supporting structure  3   a  and gives the awning  1  its form, and all such embodiments are within the ambit of the invention. 
         [0020]      FIG. 2  illustrates approximately the moment of force  7 , which acts by force of gravity, to pin the ends  4   a  of the frame  4  to the surface of supporting structure  3   a  and renders unnecessary any attachment between the two interfacing surfaces. The pivot points of the notional arm  7   c  that translates to the moment of force is the line of points between  7   a  and Tai, which is approximately the line along which the main panel  2  is detachably attached to the supporting structure  3   a . This reliance on the pinning action of gravity, acting on the ends  4   a  of the frame  4 , allows for easier erection and removal of the said awning. Also when removed, there is no remaining hardware or unsightly holes. 
         [0021]      FIG. 2  also illustrates another embodiment of the invention which detachably attaches the awning  1  to the supporting structure by means of complementary strips of loop and hook material, one  6   a  adhering to the supporting structure  3   a  and the other  6   b  being attached to the top of the main panel  2 . The two strips, when their complementary hooks and loops interlock, are all that is required to hold the awning in place. The strength of the adhesive on the back of strip  6   a  can of course vary depending upon the weight of the awning  1 . For very light awnings, the adhesive bond can be sufficiently week, such as is used in 3M Corp.&#39;s Post-its™, that it can be peeled off the supporting structure  3   a , without doing any damage to the surface of the said supporting structure  3   a . While  FIG. 2  illustrates two continuous hook and loop strips, it is to be understood that several smaller strips might be used, and be within the ambit of the invention. Also it should be noted that other preferred embodiments of the invention may utilize other means of detachably attaching the top of the main panel  4  to the supporting structure  3   a , which are all well known to the art and all of which are within the ambit of the invention. 
         [0022]      FIG. 2  also illustrates the frame  4   a , for diagrammatical clarity, outside the sleeve  5 . Frame  4   a  and  4  being one and the same. 
         [0023]      FIG. 3  illustrated an embodiment of the invention which has no side panels  2   a , but relies on the friction between the frame ends  4   a , and the supporting structure  3   a  to pin and hold the frame  4  in place. The force  7 , described above, provides the pinning force. 
         [0024]      FIG. 4  illustrates an embodiment of the invention which has no side panels  2   a , but supports the “U” shaped frame ends  4   a  by means of a hanging strip  2   b . The frame ends  4   a  may nestle in a fold  2   c  formed in the hanging strip  2   b , or any other supporting means well known to the art, and all of which are within the ambit of the invention. The hanging strip  2   b  is attached to the top of the main panel  2 . 
         [0025]    Many examples of the invention have been disclosed herein, however it is to be understood that the examples and illustrations have included many features which can be applied to each example given, in various combinations, and all are within the ambit of the invention. 
         [0026]    While the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the inventions and appended claims.

Summary:
The invention is a readily erectable and removable awning or window shade, for interior or low wind outdoor use. The structure relies for support only on detachable attachments on the top of the main panel and friction at the interface between the supporting structure and the bottom frame ends of the awning or shade.