Abstract:
A reversible sunshade for keeping the interior of a vehicle cool in the summer or heating the interior in the winter has at least one panel with a light-reflective surface and a light-absorbing surface. The sunshade may be attached to the windshield of a vehicle with suction cups that extend through holes in the panel.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    It is well known that the interiors of vehicles can become excessively hot on bright, sunny days. The intense heat not only makes it uncomfortable for the person entering the vehicle, but it can age and crack the molded polymer components on the dashboard and bleach the interior of the vehicle. This leads to costly repairs, lowers the resale values, and makes the vehicle less desirable to own over time. Any ultraviolet radiation not filtered out by the coatings on or compositions of the vehicle glass will also cause plastics and rubber to age, crack, and peel. This cause of aging proceeds as a function of incident sunlight rather than temperature. 
         [0002]    One common way to lower the temperature in the vehicle interior is to place a sunshade or visor in one or more of the windows to reflect the sunlight out of the vehicle. Conversely, a light absorbing panel may be useful in cold weather conditions for defrosting the windows or as a way of simply warming the interior prior to entering the vehicle, while at the same time shading the dashboard, etc. from ultraviolet light. 
         [0003]    While sunshades can be effective, they have thus far been limited by their methods of attachment inside the vehicle. Sunshades are often unwieldy and awkward to put in place and improper placement results in decreased reflection and higher temperatures. Therefore, a need persists for a sunshade that is easy to attach and detach while providing utility in both warm or cold conditions. 
       SUMMARY OF THE INVENTION 
       [0004]    According to one aspect of the invention, a reversible sunshade for affixation to a transparent window of an enclosure of a vehicle comprises one or more panels having a light-reflecting surface, a light-absorbing surface that is opposite the light-reflecting surface, and an outside margin forming a perimeter of the sunshade. A plurality of fasteners is adaptable to being affixed to the one or more panels at locations interior to the outside margin of the panel. 
         [0005]    The sunshade is configurable to be used in either a light reflective mode or a light-absorbing mode. In the light-reflective mode, the fasteners have a first orientation to fasten the light-reflecting surface adjacent the window such that the light reflecting surface reflects light away from the enclosure. In the light-absorbing mode, the fasteners have a second orientation to fasten the light-absorbing surface adjacent the window to absorb incident sunlight. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Further aspects of the invention and their advantages can be discerned in the following detailed description, in which like characters denote like parts and in which: 
           [0007]      FIGS. 1A and 1B  are top and bottom views according to one embodiment of the invention showing a panel with a light-reflective surface and a light-absorbing surface; 
           [0008]      FIG. 2  is an isometric view showing an enclosure of a vehicle having a sunshade according to one embodiment of the invention affixed to the windshield in a light-absorbing configuration; 
           [0009]      FIG. 3  is an isometric view of a sunshade fastener according to one embodiment of the invention; 
           [0010]      FIG. 4A  is a side view according to one embodiment of the invention showing a suction cup with an elastic, flexible, enlarged end being inserted through a hole in the sunshade, the sunshade having a light-reflecting surface oriented to be in a light-absorbing mode; 
           [0011]      FIG. 4B  is a side view according to one embodiment of the invention showing a suction cup with an elastic, flexible, enlarged end being inserted through a hole in the sunshade having a light-absorbing surface oriented to be in a light-reflecting mode; and 
           [0012]      FIG. 5  is a side view according to another embodiment of the invention showing a hook and loop fastener for attaching the suction cup to the sunshade. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Referring to  FIGS. 1A ,  1 B, and  2 , a reversible sunshade, indicated generally at  100 , for affixation to a transparent window  202  such as the front windshield of an enclosure  200  of a vehicle, comprises one or more panels  102  having a light-reflecting surface  104  and a light-absorbing surface  106  that is on the reverse side or opposite the light-reflecting surface  104 . The sunshade  100  further comprises an outside margin  108  forming a perimeter. The sunshade may be flexible or foldable to facilitate storage or installation. 
         [0014]    The sunshade  100  includes a plurality of fasteners  204 , such as four such fasteners, that are adaptable to being affixed to the panel  102  at positions that are interior to the outside margin  108  of the panel  102 . The sunshade  100  is configurable to either a light reflective mode or a light-absorbing mode. In the light-absorbing mode ( FIG. 1A and 4B ), the fasteners  204  have a first orientation to fasten the light-absorbing surface  106  adjacent the window  202  to absorb incident sunlight. In the light-reflective mode ( FIGS. 1B and 4A ), the fasteners  204  having a second orientation to fasten the light-reflecting surface  104  adjacent to the window  202  such that the light reflecting surface  104  reflects light away from the enclosure  200 . 
         [0015]    In a preferred embodiment, the one or more panels  102  have a plurality of openings  110  (such as four such openings  110 ) interior to but near the outside margin  108  of the panel  102 . Openings  110  are preferably widely spaced apart from each other and each fastener  204  cooperates with a respective opening  110  in affixing the sunshade to the window  202 . As shown in  FIG. 3 , each fastener  204  has a constriction  318  adjacent to an enlarged, flexible, elastic end  302 .  FIGS. 4A and 4B  show that the elastic end  302  is adaptable to be manually pinched or collapsed and then inserted through either side of a respective opening  110  in the panel  102 . The openings may be reinforced by grommets  400 . 
         [0016]    More preferably, the fasteners  204  include suction cups  300 . Each suction cup  300  has a disk body  304  with a rim portion  306  on a lower portion of the disk body  304 . The fasteners  204  also have a supporting base  308  formed on an upper portion of said disk body  304 , with the enlarged elastic end  302  fixedly mounted on an upper portion of the supporting base  308 . 
         [0017]    The fastener  204  may also have a drawing strip  310  affixed to the elastic end  302  for detaching the rim portion  306  from the window  202 . The drawing strip  310  has a first end portion  312  fixedly attached to the rim portion  306  of the disk body  304  and a second end portion  314  connected to the elastic end  302 . Preferably, the elastic end  302  and the supporting base  308  are integrally joined. Additionally, the elastic end  302  may further include an opening  316  to facilitate its deformation. To detach the suction cup  300  from the window  202 , the user pulls drawing strip  310  from the other side of grommet  400 , lifting an edge  312  of the suction cup  300  and thereby breaking the vacuum that the disk body  304  makes with the window. 
         [0018]    Referring to  FIG. 5 , the fasteners can, instead, incorporate hook and loop fasteners  500 . The term “hook and loop fasteners” as used herein includes fasteners that use dissimilar interlocking elements as well as interlocking elements that are the same. For example, the traditional Velcro® fasteners are an example of dissimilar interlocking elements, while Dual Lock™ fasteners sold by 3M are an example of interlocking elements that are the same. Each fastener  500  comprises a panel attachment surface  502  comprising a selected one of a hook material and a loop material. The light reflecting surface  104  has patches  504  and the light absorbing surface  106  has patches  506  of the other of the hook material and the loop material, with each patch  504 ,  506  adapted to mate with the panel attachment surface  502  of a respective fastener  500 , and with each patch  504  being in registration with a patch  506  but being on the reverse side of the panel  102 . Preferably the patches  504 ,  506  are joined to panel  102  as by means of stitching or gluing. 
         [0019]    Again, the hook and loop fasteners  500  may be used in conjunction with a plurality of suction cups  508 , with each suction cup  508  having a disk body  510  comprising a rim portion  514  on the lower portion of the disk body  510  and a supporting base  512  formed on an upper portion of the disk body  510 . The supporting base  512  of the suction cup  508  may act as the panel attachment surface  502 , receiving either the hook material or the loop material. The light-absorbing surface  106  and light-reflecting surface  104  are affixed to the other of the hook material and the loop material. 
         [0020]    As above, the panel  102  may be reversed by detaching the panel attachment surface  502  of each suction cup  508  from the either of the respective patches  504 ,  506  affixed to a given surface of the panel  102 , reversing the orientation of the panel  102 , and reattaching the other of the respective patches  504 ,  506  on the opposite surface of the panel  102  to the respective panel attachment surface  502  of each suction cup  508 . 
         [0021]    In summary, the described embodiments of the invention show an easy-to-use, reversible sunshade that may be used in a light-reflecting mode or a light-absorbing mode to reduce or increase the temperature inside a vehicle as needed. 
         [0022]    While illustrated embodiments of the present invention have been described and illustrated in the appended drawings, the present invention is not limited thereto but only by the scope and spirit of the appended claims.