Abstract:
A raised lap top work surface utilizes a concave area for comfortable use and positioning on a user&#39;s legs. V-shaped arching leg support surfaces provide reliable positioning of the raised lap top work surface on the user&#39;s lap. The raised lap top work surface has a raised working surface level located at the proper sight distance for reading or writing. A large cover gives the user a surface area large enough to display any reference material needed and still have ample room for writing.

Description:
RELATED APPLICATIONS 
   The present application is related to U.S. Provisional Application filed Jun. 17, 2002. 
   FIELD OF THE INVENTION 
   The present invention is in the field of portable lap desks adapted for doing close up work without having to bend over or to strain the eyes. 
   BACKGROUND OF THE INVENTION 
   Portable desks are well known and are used to supply a user with a writing or supporting surface in a place where no support is provided. A common area for using a portable desk is in a vehicle. During long trips a portable desk can be used to read a book or support a laptop computer. Children use portable desks in vehicles to color or prepare homework assignments. 
   There have been various patents which solve problems presented by portable desks which are currently on the market. Most portable desks are made of plastic but when not in use take up too much space. The plastic portable desks are also heavy making it difficult for a child or an elderly person to position and handle. Jennings U.S. Pat. No. 4,052,944 and Mills U.S. Pat. No. 4,700,634 disclose portable desks with cushion support for the user&#39;s legs. 
   A patent which has addressed some of these issues is that to Drieling U.S. Pat. No. 5,081,936. The Drieling patent discloses a compressible desk arrangement including a desk made of flexible foam with a rubber coating. The concept presented by Drieling is to provide a desk which may be collapsed by compressing the desk into a storage position. Unfortunately, the desk presented by Drieling is not practical because the desk is expensive to manufacture, and the supporting structure is not rigid enough to provide a solid support surface for writing or working. 
   There is a need for a portable desk which is lightweight, rigid and squares the user&#39;s legs for securing the desk. There is still another need to provide a portable desk having a hard surface but rests comfortably on the user&#39;s legs. Finally, there is a need for a portable desk having a raised working surface level at, or near, the proper sight distance for reading or writing; and at the same time, to provide a surface area large enough to display any reference material needed and still have ample room for writing. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a raised lap fitted work top which provides a user with a work-top suitable for doing close-up work without having to bend over, or to strain the eyes. 
   Another object of the present invention is to provide a portable desk made rigid with light weight cellular polystyrene. 
   Another object of the present invention is to provide a portable desk having a raised working surface level at, or near, the proper sight distance for reading or writing; and at the same time, to provide a surface area large enough to display any reference material needed and still have ample room for writing. 
   The present invention makes use of the leg tops for support as does similar patented items, but unlike other patented lap oriented tops, the unit is designed to fit the top of the legs when the legs are slightly spread. This spreading of the legs provides a larger supporting area for the unit, and allows the unit to be made larger without fear of the top from becoming unbalanced, causing the unit to tip to one side. The V-shape of the spread legs, also, resists any forward movement of the unit resting on the legs. 

   
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a raised lap-fitted work-top device according to one embodiment of the present invention. 
       FIG. 2  is a front perspective view of the raised lap-fitted work-top device of the present invention. 
       FIG. 3  is a rear view of the raised lap-fitted work-top device of the present invention. 
       FIG. 4  is a side cross sectional view taken along lines  1 — 1  of  FIG. 2  illustrating the raised lap-fitted work-top device of the present invention. 
       FIG. 5  is a top view with broken lines illustrating the positioning angle of the legs of the user. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is directed to a raised lap fitted work top. The raised lap fitted work top or portable desk is described in  FIGS. 1–4 . Although the Figures illustrate the desk having sharp edges and corners the edges and corners may be round or chamfered to prevent pinching. The portable desk of the present invention will now be described in detail. 
     FIG. 1  discloses a portable lap desk  10  having a main body portion  11  and a cover  12 . The cover  12  is made of laminated cardboard or plastic to provide a hard outer surface  13 . As illustrated in  FIG. 1 , the cover is provided with a container holder  14  and a plurality of pencil holders  15 . There may be more than one container holder  14  or more than two pencil holders  15  formed in the cover  12  and in the lower body portion  11 . The container holder is a circular depression about 3 inches wide in diameter and 4 inches deep. 
   The lower body portion  11  is made from lightweight polystyrene or Styrafoam and is cut into shape or may be molded to the shape illustrated in  FIGS. 1–4 . The lower body portion  11  has a front wall  20 , side walls  21 ,  22 , a rear wall  23  and a bottom portion  24 . The rear wall  23  is concave in shape to conform to the user&#39;s waist area. Illustrated in  FIG. 3  is a shelf  26  which is integrally formed in the lower body portion. The shelf may be used to hold newspapers, books, small craft items and papers for future use. The shelf provides the use of the lap top as a side bin when turned so that the shelf is facing upward. 
   As illustrated in  FIGS. 2–4 , the main body portion  11  has means  30  for positioning a user&#39;s legs to support the portable lap desk  10 . The means  30  is formed in the bottom portion  24  and includes arching supporting surfaces  31 ,  32  which rise in height relative to the plane of the bottom wall to compensate for the natural slope of the legs in a sitting position. Arching supporting surfaces  31 ,  32  extend from the rear wall  23  to the front wall  20 . Each arching supporting surface  31 ,  32  also narrows in width from the rear wall  23  to the front wall  20 . Arching supporting surface  31  extends to the front wall  20  at an angle of approximately 135 degrees relative to the plane of the rear wall and at an angle of 135–160 degrees relative to the plane of the bottom wall. Arching supporting surface  32  extends to the front wall  20  at an angle of 45 degrees relative to the plane of the rear wall  23 . The arching supporting surfaces rest on the user&#39;s legs and provide means for spreading the user&#39;s legs at an angle of approximately 40 degrees relative to each other. Anywhere from 35–55 degrees to form a V-shaped angle provides enough support for the user. The angles may range from 125–145 degrees for arch support surface  31  and 35–55 for arch support surface  32 . The V-shape of the spread legs resists any forward movement of the portable lap desk  10  resting on the legs. 
   Arching supporting surface  31  extends into an opening  35  in the front wall  20  and extends into an opening  36  in the rear wall  23 . Arching supporting surface  32  extends into an opening  37  in the front wall and into an opening  38  in the rear wall  23 . The openings in the rear wall  36 ,  38  are larger than the openings  35 ,  37  in the front wall  20 . The concept of utilizing the lap desk to spread the user&#39;s legs provides a larger supporting area for the lap desk  10 , and allows the lap desk  10  to be made larger without fear of the top from becoming unbalanced, causing the lap desk  10  to tip to one side. 
   Formed between the supporting surfaces  31 ,  32  is a dividing member  40 . The dividing member has a rear portion  41  which extends at an angle toward the user but not as far down as the bottom portion  24 . The rear portion  41  of the dividing member assists the user in positioning the lap desk  10  on the thighs of the user by limiting the extension of the rear portion  41 . The rear wall  23  is further provided with feet  41 ,  42  which also assist the user in positioning the desk on the user&#39;s thighs. The broken lines in  FIG. 2  illustrate the shape of the arches  31 ,  32  as they pass through the raised lap fitted work top  10 . 
     FIG. 4  illustrates a side cross sectional view taken along lines  1 — 1  of  FIG. 2 . Concave area  44  provides a comfortable positioning and support surface for handicapped or elderly individuals. The concave area  44  rests against the user&#39;s waistline and because of the concave shape the user is not gouged by the lower body portion  11 .  FIG. 4  also illustrates the lightweight cellular polystyrene material used to make the main body portion  11  and the laminated cardboard or plastic material used to make the cover  12 . 
   The dimensions of the raised lap fitted work top are an important part of the concept. The front end of the cover  12  is made to rest about 7 inches above the knees of the user. The back end of the cover is made to rest about 4 inches above the thighs. The 3 inch differential compensates for the natural slope along the legs from the thighs to the knees, and provides some extra rise so as to cause the cover to tilt slightly toward the user. 
   The lap desk structure provides an easy to lift supporting surface especially designed for elderly or handicapped individuals. The lap desk may also be used as a side table or a side bin or in any situation where a small supporting surface is needed. For use while sitting down, the raised lap fitted work top provides a user with a work-top suitable for doing close-up work without having to bend over, or strain the eyes.