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This application claims priority from U.S. patent application Ser. No. 10/086,514 filed Feb. 28, 2002 now U.S. Pat. No. 6,763,841 and U.S. Provisional Application Ser. No. 60/272,385 filed Feb. 28 2001, which have the same inventor as the present application. 
   FIELD 
   The present invention relates generally to portable living structures and specifically to tents. 
   BACKGROUND  
   Tents have been used for centuries as temporary structures for camping trips. During these trips, there may be competing desires for comfort on one hand, while a camper may still desire to get away from the complications of city life. The use of lightweight materials has made the satisfaction of these competing desires more easily accomplished. Tent fabrics, as well as tent poles and frame structures, can now be made to be very strong, while also very lightweight. This use of materials allows more imaginative and varied structures to be designed, which are still light enough to be easily portable, and thus practical for camping trips. 
   Another pair of competing needs facing campers and users of tents is that of the need for a reasonably small floor space, while providing enough internal volume for comfort. When camping in the woods, the extent of usable flat ground area may be limited, by trees or uneven terrain, thus a tent which has a large “footprint” or floor area will find fewer useable sites than one that has a smaller footprint. At the same time, a user will generally feel a need for “elbow room” and may feel cramped without a reasonable amount of space. 
   Thus there is a need for a tent which has a compact footprint, but which has an interior volume which is greater than that of a tent having the traditional inwardly tapering, or even strictly vertical walls. 
   SUMMARY 
   Accordingly, it is an object of the present invention to provide a tent which has a compact footprint. 
   Another object of the invention is to provide a tent which has an enlarged internal enclosed volume. 
   And another object of the invention is to provide windows which are protected from rain entry. 
   A further object of the present invention is to provide windows which are extended from the main body of the tent, and thus enlarge the interior volume. 
   Briefly, one preferred embodiment of the present invention is a tent with extendable windows having a main structure including a plurality of walls which are oriented at a first angle with respect to a vertical reference. The tent also includes at least one window which is extendable to a second angle with respect to a vertical reference, where the second angle is a more negative angle than the first angle thus producing windows which are extendable horizontally further than the tent walls. 
   An advantage of the present invention is that it provides extendable windows which extend from the main volume of the tent, and thus enlarge it. 
   Another advantage of the present invention is that the extendable windows can be retracted against the tent sides if necessary. 
   And another advantage of the present invention is that the extendable windows have a water-proof awning portion, and the screen area of each window slopes negatively back towards the main tent structure, thus preventing rain from entering. 
   A further advantage of the present invention is that the extendable windows provide an enlarged volume area at or around a typical adults&#39; head, shoulder and torso area, thus providing enlarged volume in the area where more adults are largest, rather than down by their feet. 
   A yet further advantage is that the enlarged volume provides a psychological feeling of being less cramped to some people, which may be out of proportion to the actual increase in volume achieved. 
   These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of the best presently known mode of carrying out the invention and the industrial applicability of the preferred embodiment as described herein and as illustrated in the several figures of the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The purposes and advantages of the present invention will be apparent from the following detailed description in conjunction with the appended drawings in which: 
       FIG. 1  shows an isometric front view of a tent with extendable windows having an open screen roof. 
       FIG. 2  illustrates a front plan view of a tent with extendable windows; 
       FIG. 3  shows a side plan view of a tent with extendable windows; and 
       FIG. 4  illustrates an isometric view of a tent with extendable windows having a soffited roof. 
   

   DETAILED DESCRIPTION 
   A preferred embodiment of the present invention is a tent with extendable windows. As illustrated in the various drawings herein, and particularly in the view of  FIG. 1 , a form of this preferred embodiment of the inventive device is depicted by the general reference character  10 . 
     FIG. 1  illustrates an isometric view of a tent with extendable windows  10 . The configuration of the actual tent main structure  12  may have many different forms and variations for which the extendable windows  14  of the present invention are suitable. The tent will generally include a front wall  16 , a rear wall  18 , side walls  20 , a floor  22  and a roof or ceiling  24 . In this figure, the roof  24  is open except for a screen  26 , whereas in  FIG. 4 , below, the roof is a soffited roof  28  with an overhanging portion  30 . 
   In  FIGS. 1 and 3 , there are shown to be two extendable windows  14 , which are on either side wall  20  of the tent  10 . This is of course one variation among many, as the rear wall  18  may, in other designs, include a extendable window, for a total of three, or there may be only one extendable window  14 , or there may multiple smaller extendable windows along one side wall  20 , in tents which have longer side walls  20  compared to the width of the front wall  16  shown here. 
   Referring now also to  FIGS. 2-4 , the extendable window  14  includes an upper panel or awning  32 , which is preferably water-proof or water resistant, and joined at a rear seam  34  to the main body of the tent  12 . The extendable window  14  also preferably includes a frame  36 , which in turn is preferably made up of several segments  38  which link together to form a bow-shaped member, roughly parabolic in shape, although this shape is not a requirement. The segments  38  may be completely detachable from each other, or they may be joined by an internal elastic cord  40  (not visible), which keeps the segments  38  together in proper order, but still allows the frame  36  to be folded for easy storage. 
   As seen especially in  FIGS. 1 and 2 , the extendable window  14  includes a cloth or fabric sleeve  42  into which the frame  36  fits. There are preferably openings  44  in the sleeve  42  through which the end of the frame  36  may be inserted. These opening  44  may be at various locations in the sleeve  42  and are not limited to the location shown. 
   The extendable window  14  also includes a screen portion  46 , which is used to keep out insects, etc., and may include window flaps  48  or curtains, which can be zipped together to keep out wind, light and to ensure privacy. These window flaps  48  may be internal or external to the tent main body  12 , but are preferred to be internal. 
   The extendable window  14  also includes a bat wing panel  50  located at or near the leading edge  52  of the extendable window  14 . This bat wing panel  50  acts as an attachment site for a guy rope or wire  54 . The guy wire  54  is attached to a stake (not shown) or branch or other anchoring object, and serves to keep the extendable window  14  expanded to its full extent. The extendable window  14  has a hinge portion  59 , in a manner of speaking, at its lower attachment seam  58 , as the fabric to which the sleeve  42  ends are fastened, allow the frame  36  to pivot forward when the extendable window  14  is extended, as when tensioned by the guy wire  54 . The extendable window  14  is however retractable to some extent, as for instance, when the camp site space is limited, and the extendable windows  14  would otherwise project into bushes or tree branches. In these cases, the frames  36  may be pivoted back towards the side walls  20  and perhaps fastened in place by VELCRO® loops, etc. 
   The side walls  20  shown in the figures slope inward in a conventional manner so that the floor area  22  is larger than the ceiling area  24 . Thus a window which is co-planar with the walls  20  (which are generally at some positive angle α  60  with respect to a vertical line), would be expected to receive some run-off during rain storms, or some amount of the rain falling vertically in that area. However, the tent with extendable windows  10  has the advantage that the extendable windows  14  extend out past vertical to present a negatively sloped angle β  62  to the screen  46 , as can be seen in  FIG. 2 . The water-proof or water resistant awning  32  protects the window  14  from rain intrusion which falls vertically, and even prevents some component of wind-blown rain traveling at less than the negative angle β  62 . The window may also be at a positive angle β  62 , which is less positive (and thus more negative) than angle α  60  of the walls  20 . Thus, when the angle of the windows is spoken of as more negative than the slope of the walls, it includes cases where the angle β is negative, where angle β is positive but less positive than the angle α, or when the angle β is vertical and angle α is positive. For purposes of this discussion, a positive angle is considered to extend in a counter-clockwise direction from a vertical reference, and a negative angle is assumed to extend in a clockwise direction. 
   The frame  36  gives a defined shape to the extendable window  14 , but it is also possible to have a variation without a rigid frame, or perhaps no frame at all if additional guy wires or ropes are attached to the leading edge  52 . 
   An advantage of the present invention  10  is that it provides additional space near the region of the average adult&#39;s head and shoulders, a space which is typically constricted by the inward sloping of the walls. Most humans are wider near the shoulder area or torso area, rather than at foot or knee-height. Additionally, most humans form their perception of being “cramped” or “crowded” from visual cues received from head height. By adding volume near the shoulder and head area, without effecting the floor area, the tent may be perceived as being much more comfortable and roomy, while still maintaining a compact “footprint” or floor area. The compact footprint will generally enable the user a larger selection of usable camp sites than one with a larger footprint. 
   While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of a preferred embodiment should not be limited by any of the above described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. 
   The present tent with extendable windows  10  is well suited for application in the home, backyard, or on camping trips and picnics. 
   The tent will generally include a front wall  16 , a rear wall  18 , side walls  20 , a floor  22  and a roof or ceiling  24 . One or more extendable windows  14  are included on either side wall  20  of the tent  10 . The extendable windows  14  each include an upper panel or awning  32 , which is preferably water-proof or water resistant, and joined at a rear seam  34  to the main body of the tent  12 . The extendable window  14  also preferably includes a frame  36 , which in turn is preferably made up of several segments  38  which link together to form a bow-shaped member, preferably roughly parabolic in shape. The segments  38  may be completely detachable from each other, or they may be joined by an internal elastic cord  40 , which keeps the segments  38  together in proper order, but still allows the frame  36  to be folded for easy storage. 
   The side walls  20  generally slope inward in a conventional manner so that the floor area  22  is larger than the ceiling area  24 . The extendable windows  14  preferably extend out past vertical to present a negatively sloped angle β  62  to the screen  46 . The water-proof or water resistant awning  32  protects the window  14  from rain intrusion which falls vertically, and even prevents some component of wind-blown rain traveling at less than the negative angle β  62 . The window may also be at a positive angle β  62 , which is less positive (and thus more negative) than angle α  60  of the walls  20 . The frame  36  gives a defined shape to the extendable window  14 , but it is also possible to have a variation without a rigid frame, or perhaps no frame at all if additional guy wires or ropes are attached to the leading edge  52 . 
   The present invention  10  provides additional space near the region of the average adult&#39;s head and shoulders, a space which is typically constricted by the inward sloping of the walls. Most humans are wider near the shoulder area or torso area, rather than at foot or knee-height. Additionally, most humans form their perception of being “cramped” or “crowded” from visual cues received from head height. By adding volume near the shoulder and head area, without effecting the floor area, the tent may be perceived as being much more comfortable and roomy, while still maintaining a compact “footprint” or floor area. The compact footprint will generally enable the user a larger selection of usable camp sites than one with a larger footprint. Thus, the tent  10  is useful in many camping situations and is expected to be popular with users. 
   For the above and other reasons, it is expected that the tent with extendable windows  10  of the present invention will have widespread industrial applicability. Therefore, it is expected that the commercial utility of the present invention will be extensive and long lasting.

Summary:
A tent ( 10 ) with extendable windows ( 14 ) having a main structure ( 12 ) including a plurality of walls ( 16, 18, 20 ) which are oriented at a first angle ( 60 ) with respect to a vertical reference. The tent ( 10 ) also includes at least one window ( 14 ) which is extendable to a second angle ( 62 ) with respect to a vertical reference, where the second angle ( 62 ) is a more negative angle than the first angle ( 60 ) thus producing windows ( 14 ) which are horizontally extendable further than the tent walls ( 16, 18, 20 ).