Abstract:
A cover is disclosed for a pickup truck bed with the cover being comprised of upper and lower metal sheet members secured at their edges to define a compartment therebetween which is preferably filled with a foam strengthening material. Preferably, the sheet members are constructed of an aluminum material.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a cover for a pickup truck bed and more particularly to a cover for a pickup truck bed which comprises upper and lower metal sheet members joined together at the edges thereof and which a define compartment therebetween. In the preferred embodiment, the compartment is filled with a strengthening foam. 
     2. Description of the Related Art 
     Covers or lids for pickup truck beds are commonly used which are extended over the upper end of a truck bed to provide a safe and dry cargo area. Traditionally, the covers or lids are constructed of a plastic material or a fiberglass material. The plastic and fiberglass covers are affected by the elements and tend to fade over time and sometimes are chipped through use. Additionally, the conventional plastic or fiberglass covers are quite heavy. In those cases where metal is used for the covers, it is necessary to weld the same. 
     SUMMARY OF THE INVENTION 
     A cover is disclosed for a pickup truck bed having an upstanding front wall, upstanding opposite side walls, and a tailgate which is movable between open and closed positions. The cover of this invention comprises an upper metal sheet member having a front edge, opposite side edges, and a rear edge with the upper sheet member having an upper surface and a lower surface. The cover also includes a lower metal sheet member having a front edge, opposite side edges, and a rear edge, with the lower sheet member having an upper surface and a lower surface. The upper surface of the front edge of the lower sheet member is glued to the lower surface of the front edge member of the upper sheet member. The upper surfaces of the side edges of the lower sheet member are glued to the lower surfaces of the side edges of the upper sheet member. The upper surface of the rear edge of the lower sheet member is glued to the lower surface of the rear edge of the upper sheet member. The upper sheet member has an upwardly domed central portion with the upper and lower sheet members defining a compartment therebetween with the compartment being preferably filled with a strengthening foam. Preferably, the metal sheet members are comprised of an aluminum material. Although the preferred embodiment utilizes glue to secure the sheet members together, the sheet members could be secured together by welding or other mechanical means. In a modified form of the invention, an expansion bead is formed in the lower sheet member adjacent each of its side edges. 
     It is therefore a principal object of the invention to provide an improved cover for a pickup truck bed. 
     A further object of the invention is to provide a cover for a pickup truck bed which is comprised of a metal material. 
     Still another object of the invention is to provide a cover for a pickup truck bed having a dome formed thereon to ensure that the water will run off the cover and will not accumulate in the middle thereof. 
     Still another object of the invention is to provide a cover for a pickup truck bed which is made of a material which will not be affected by the elements. 
     Still another object of the invention is to provide a lightweight cover for a pickup truck bed. 
     Still another object of the invention is to provide a metal cover for a pickup truck bed wherein upper and lower sheet members are preferably glued together rather than being welded. 
     Still another object of the invention is to provide a cover for a pickup truck bed including upper and lower sheet members which define a compartment therebetween with the compartment being filled with foam to create rigidity in the cover. 
     Still another object of the invention is to provide a cover for a pickup truck bed which is extremely strong. 
     These and other objects will be apparent to those skilled in the art. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a pickup truck having the lid of this invention mounted thereon; 
     FIG. 2 is a sectional view as seen on lines  2 — 2  of FIG. 1; 
     FIG. 3 is an enlarged partial sectional view of FIG. 2; 
     FIG. 4 is a sectional view as seen on lines  4 — 4  of FIG. 2; 
     FIG. 5 is a view similar to FIG. 3 except that a modified embodiment is shown; and 
     FIG. 6 is a view similar to FIG. 3 except that a further modified embodiment is shown. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1, the numeral  10  refers to a pickup truck including a bed  12  which includes a conventional upstanding front wall, upstanding side walls, and a tailgate. The numeral  14  refers to the lid of this invention. 
     Lid  10  includes an upper sheet member  16  and a lower sheet member  18  which are constructed of a metal material which is preferably aluminum. Upper sheet member  16  includes a front edge  20 , rear edge  30 , and opposite side edges  32  and  34 . For purposes of description, upper sheet member  16  will be described as having an upper surface  36  and a lower surface  38 . Preferably, upper sheet member  16  has a central domed portion  40  which causes water to drain therefrom and to prevent the accumulation of water thereon. As seen in the drawings, the opposite side edges  32  and  34  extend downwardly and outwardly. Front edge  20  and rear edge  30  also extend downwardly somewhat, but to a lesser degree than the opposite side edges  32  and  34 . In many cases, the downwardly extending portion at the front edge of upper sheet member  16  will be omitted. 
     Lower sheet member  18  includes a front edge  42 , rear edge  44 , and opposite side edges  46  and  48 . For purposes of description, lower sheet member  18  will be described as having an upper surface  50  and lower surface  52 . 
     Lower sheet member  18  is positioned below upper sheet member  16 , as illustrated in the drawings, with the upper surfaces of edges  42 ,  44 ,  46  and  48  thereof being glued to the lower surfaces of edges  20 ,  30 ,  32  and  34 , respectively, by a suitable adhesive. Although gluing is preferred, the sheet members could be welded together or secured together by other mechanical fastening means. Preferably, a suitable strengthening foam  54  is injected between the upper sheet member  16  and lower sheet member  18  to fill the compartment between sheet members  16  and  18 . The foam material creates a truss-style strengthening system when the foam is used between the sheet members  16  and  18 . The foam also creates rigidity for the cover. In some situations, it may be necessary to utilize some sort of truss structure between the sheet members to prevent warping of the cover in extremely hot temperatures. In those situations, the foam may not be required. 
     The lid  14  of this invention is quite lightweight and which will have a weight of approximately 35-75 pounds. The use of the aluminum sheet members  16  and  18  provides a cover or lid which will keep the contents in the truck bed dry and secure. The construction of the lid  14  is such that it will not be affected by the elements. Further, the sheet members  16  and  18  may be formed to fit specific models of pickup trucks. The use of glue to secure the sheet members  16  and  18  together eliminates the need for welding the sheet members together, although welding may be employed if necessary or desirable. The lid or cover of this invention is extremely strong and will be many times stronger than fiberglass or plastic. 
     FIG. 5 illustrates an embodiment wherein the side edges of the upper sheet member  16 A and the lower sheet member  18 A are straight, rather than being arcuate. 
     FIG. 6 illustrates a further embodiment wherein an expansion bead  70  is formed in lower sheet member  18 A adjacent each of the sides thereof. 
     Thus it can be seen that the invention accomplishes at least all of its stated objectives.