Abstract:
The present truck bed cap consists of an internal frame having a first shelf, a second shelf and a top, wherein the internal frame is connected to corner supports attached to the bed of the truck. In a first motion the top shifts vertically with respect to the internal frame. In a second motion the internal frame shifts vertically with respect to the corner supports and the bed of the truck.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a non-provisional application claiming the benefit, pursuant to 37 C.F.R. §1.53(c), of an earlier-filed provisional application. The provisional application was filed on Oct. 27, 2009 and was assigned application Ser. No. 61/255,432. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     MICROFICHE APPENDIX 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of truck covers. More specifically, the invention comprises a truck bed cap having a storage system that shifts vertically with respect to the bed of a pickup truck. 
     2. Description of the Related Art 
     Pick-up trucks are often used for transporting tools, luggage, hardware and other materials in the bed of the truck. Typically, in order to protect and semi-permanently store the items being transported a camper shell, also known as a truck bed cap, is utilized. The truck bed cap generally covers the entirety of the pickup truck bed and is as tall as the top of the truck cabin. 
     A prior art truck bed cap  12  is shown in  FIG. 1 . Prior art truck bed cap  12  forms a seal around truck bed  10 . In order to access the stored items prior art truck bed caps  12  have been equipped with shelves  16  and side and back doors  14 ,  22 , as shown in  FIG. 2 . When side door  14  is opened the user can access stored items  18 . However, only those items stored on shelves  16  can be accessed via side door  14 . Any item stored underneath shelves  16  must be accessed by way of hinged rear tailgate  24 . While longer items may reach the forward facing portion of the truck bed, it is unlikely that the space near the front of the bed will be fully utilized due to the inaccessible nature of this area under the present design. 
     Therefore what is needed is a truck bed cap which can efficiently utilize the space in the forward facing portion of the truck bed and simplify access to all stored items. The present invention achieves this objective, as well as others that are explained in the following description. 
     BRIEF SUMMARY OF THE PRESENT INVENTION 
     The present invention is a truck bed cap for easily accessing items in the bed of a truck. The present truck bed cap generally consists of a first shelf and a second shelf attached to an internal frame, wherein the internal frame is engaged with four corner supports. A top is connected to the internal frame. The top shifts vertically with respect to the internal frame and the shelves shift vertically with respect to the four corner supports and the bed of the truck. When in a closed position, the top of the truck bed cap meets the top of truck bed such that it forms a seal around truck bed. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a perspective view, showing a prior art truck bed cap. 
         FIG. 2  is a perspective view, showing a prior art truck bed cap opened at a side door. 
         FIG. 3  is a perspective view, showing the preferred embodiment of the present invention in a closed position. 
         FIG. 4  is a perspective view, showing the preferred embodiment of the present invention in a partially open position. 
         FIG. 5  is a perspective view, showing the preferred embodiment in a partially open position with storage unit uninstalled. 
         FIG. 6  is a perspective view, showing the preferred embodiment in a partially open position with storage unit installed. 
         FIG. 7  is a perspective view, showing the preferred embodiment of the present invention in a fully open and raised position. 
         FIG. 8  is a section view, showing the present invention in a fully open and raised position. 
         FIG. 8A  is a section view, showing a view from the back of the present invention, wherein the shelves are in a raised position. 
         FIG. 9  is a section view, showing the present invention in a partially open position. 
         FIG. 9A  is a section view, showing a view from the back of the present invention, wherein the shelves are in a lowered position. 
         FIG. 10  is a section view, showing the present invention in a fully closed position. 
         FIG. 10A  is a plan view, showing the gear system from the top of the present invention. 
         FIG. 11  is a perspective view, showing the top of internal frame and the present invention with the scissor lifts raised. 
         FIG. 12  is a section view, showing an alternate embodiment of the present invention. 
         FIG. 13  is a perspective view, showing an alternate embodiment of the present invention with only one shelf. 
         FIG. 14  is a perspective view, showing an alternate embodiment of the present invention with a shortened first shelf. 
         FIG. 15  is a perspective view, showing the manner of operation of the gear system of the present operation. 
     
    
    
     REFERENCE NUMERALS IN THE DRAWINGS 
     
       
         
               
               
               
               
             
           
               
                   
               
             
             
               
                 10 
                 truck bed 
                 12 
                 prior art truck bed cap 
               
               
                 14 
                 door 
                 16 
                 shelves 
               
               
                 18 
                 stored items 
                 20 
                 truck 
               
               
                 22 
                 bed cover back door 
                 24 
                 hinged rear tailgate 
               
               
                 26 
                 truck bed cap 
                 28 
                 top 
               
               
                 30 
                 internal frame 
                 32 
                 first shelf 
               
               
                 34 
                 second shelf 
                 36 
                 arm assembly 
               
               
                 38 
                 bearings 
                 40 
                 pivot pin 
               
               
                 42 
                 drive shaft 
                 44 
                 gear motor 
               
               
                 46 
                 gear box 
                 48 
                 lifting post 
               
               
                 50 
                 screw 
                 52 
                 truck bed 
               
               
                 54 
                 lock 
                 56 
                 tail gate 
               
               
                 58 
                 corner support 
                 60 
                 electric screw jack 
               
               
                 62 
                 winch 
                 64 
                 large item 
               
               
                 66 
                 cable 
                 68 
                 bar 
               
               
                 70 
                 groove 
                 72 
                 storage unit 
               
               
                 74 
                 winch cable 
                 76 
                 safety line 
               
               
                 78 
                 top gear motor 
                 80 
                 nut 
               
               
                 82 
                 input 
                 84 
                 extension 
               
               
                 86 
                 input drive shaft 
                 88 
                 lip 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 3  illustrates truck bed cap  26  installed in a closed position on truck  20 . In the closed position, the user can easily transport or store any items in truck bed cap  26 . Top  28  of truck bed cap  26  fully encloses and forms a seal around truck bed  10 . Top  28  does not contain any doors or windows in the preferred embodiment, however, the reader will appreciate that the addition of doors or windows would not materially change the nature of truck bed cap  26 . Top  28  of truck bed cap  26  is preferably made from a lightweight material, such as aluminum or molded plastic, however one skilled in the art will recognize that top  28  could be made of many different materials to create a weather resistant seal around truck bed  10 . 
     Additionally, top  28  of truck bed cap  26  preferably contains a lock  54  which extends over tail gate  56 , to prevent unwanted access to contents stored inside of truck bed cap  26 . Any conventional locking system could be utilized. 
     When the user desires to access stored items  18 , a remote switch is utilized to begin to shift top  28  vertically with respect to internal frame  30  of truck bed cap  26  as illustrated in  FIG. 4  (arrows show the direction of movement of top  28 ). Once top  28  is lifted exposing first shelf  32 , stored items  18  located on first shelf  32  can be easily accessed. The user can reach to the center of first shelf  32  while standing along the side of truck bed  10  or from the back of truck bed  10 . Three of the four sides of first shelf  32  are fully unobstructed. As illustrated first shelf  32  extends the full length of truck bed  10  in the preferred embodiment. While this embodiment is preferable, first shelf  32 , in the alternative, can extend less than the full length of truck bed  52 . This alternative embodiment creates a larger vertical space near the rear of truck bed  10  where large items  64 , such as lawnmowers can be stored (as illustrated in  FIG. 14 ). This embodiment does not alter the function of the present truck bed cap  26 . 
     Additionally, first shelf  32  can contain a storage unit  72 .  FIG. 5  shows a storage unit  72  which is removable. Storage unit  72  can be temporarily attached by any known means.  FIG. 6  shows storage unit  72  after being installed on first shelf  32 . In the alternative, storage unit  72  could be permanently integrated with first shelf  32 . 
     If the user desires to access stored items  18  underneath first shelf  32 , the user again uses a remote switch to begin to shift internal frame  30  vertically with respect to truck bed  10 , as shown in  FIG. 7 . When internal frame  30  is raised such that second shelf  34  is close to or level with the top of truck bed  10 , the user can easily access all stored items  18  located on second shelf  34 . Second shelf  34  preferably extends the length of truck bed  52 . It is in this manner that the full space of truck bed  10  can be utilized. 
     A section view is shown in  FIG. 8  to better illustrate the preferred method of operating the present truck bed cap  26 .  FIG. 8  shows the truck bed cap  26  in a fully expanded or open position, wherein second shelf  34  is approximately level with top of truck bed  52 . In the preferred embodiment a series of commonly driven lifting posts  48  will be associated with each corner support  58 . Each lifting post  48  is preferably a threaded lifting screw which when activated lowers and raises internal frame  30  thereby lowering and raising first shelf  32  and second shelf  34 . 
       FIG. 8A , showing a section view from the back of the truck, better illustrates the mechanics of lifting post  48 . First shelf  32  and second shelf  34  move up and down as one unit on corner post  58  as extension  84  moves up or down driving by the action of lifting post  48 . Lifting post  48  is operated by a gear within gear box  46  and drive shaft  42 . The specific mechanics of gears are not shown, as one knowledgeable in the art will understand the operation of gear boxes  46 . In  FIG. 15  the reader will observe that as drive shaft  42  rotates, lifting post  48  moves up or down through gear box  46 , dependent on the direction of rotation of drive shaft  42 . 
     As illustrated in  FIG. 9 , second shelf  34  lowers to meet truck bed  52  when lifting posts  48  are lowered by gear system. In this view, first shelf  32  sits approximately at the same level as the top of truck bed  52 . Thus, the user can easily access first shelf  32  in this position. Drive shaft  42  extends between gears  46  in corner supports  58 . 
       FIG. 9A  shows a section view from the back of the truck, where second shelf  34  is lowered to truck bed  52 . Lifting post  48  has been threaded through gear box  46  bringing extension  84  and internal frame  30  to a lowered position. 
     The full gear system is illustrated in a plan view in  FIG. 10A . Gear motor  44 , located at the front or back of truck, activates input drive shafts  86  and drive shafts  42 . Input  82  operates in conjunction with gear boxes  46  and as drive shafts  42  rotate, lifting posts (shown in  FIGS. 8A ,  9 A and  15 ) are driven up or down. The user can activate gear motor  44  via a remote control. 
     While a gear motor  44  and lifting posts  48  are used in the present embodiment, one skilled in the art will recognize that any device that is able to shift internal frame  30  vertically with regard to truck bed  52  could be used. For example, an electric screw jack  60  could be placed in the center of internal frame  30  to move internal frame  30  with respect to truck bed  52  as shown in  FIG. 12 . Additionally, lifting posts  48  could be located within corner posts  58  such that the system is partially hidden. 
     As illustrated in  FIG. 11 , top  28  is preferably raised and lower by a scissor lift comprised generally of two arm assemblies  36 . Pivot pins  40  are securely attached to the top of internal frame  30  and top  28 . Bearings  38  roll along internal frame  30  and top  28  as top gear motor  78  operates to pull arm assemblies  36  up and down. Top gear motor  78  is preferably a gear motor screw set up. A perspective view of scissor lift is shown in  FIG. 11 . In the preferred embodiment there are two arm assemblies  36  attached together by a solid bar  68 . Bearings  38  roll along internal frame  30  at a groove. While top  28  is not shown in  FIG. 11 , the reader will note that a similar groove would allow bearings  38  on top of arm assemblies  36  to move along underside of top  28 , preferably along an attached rail rather than into the top directly. As top gear motor  78  pulls and releases screw  50 ; bar  68  acts to move arm assemblies  36  up and down at the same time. As illustrated in  FIG. 9 , when scissor lift is fully raised top  28  sits well above first shelf  32  allowing access to first shelf  32  by user. When scissor lift is fully lowered top  28  rests nearly even with top of internal frame  30  and contacts the top of truck bed  52 , as shown in  FIG. 10 . Top  28  could optionally contain lip  88  which creates added protection from water seeping into truck bed  52 . Additionally, top gear motor  78  can contain a current sensing circuit which shuts down top gear motor  78  if an increased load is detected upon lowering the cap, for added safety (this feature is not described further as implementation of the feature is known in the prior art). 
     An alternate embodiment of the scissor lift system is shown in  FIG. 12 . In  FIG. 12  winch  62  pulls winch cable  74  back and forth, raising and lowering the arm assemblies  36 . If the arm assemblies  36  are pulled too high a safety line  76  will act to unplug winch  42 , as shown. 
     Another alternate embodiment of the present truck cap  26  is shown in  FIG. 13 , wherein shelf  34  extends the full length of the truck bed  52 . In this embodiment shelf  34  is to only shelf attached to internal frame  30  and is the only shelf within the present truck cap  26  structure. 
     The preceding description contains significant detail regarding the novel aspects of the present invention. It should not be construed, however, as limiting the scope of the invention but rather as providing illustrations of the preferred embodiments of the invention. As an example, scissor lift system could be replaced by an automatic hydraulic system for raising and lowering top  28 . Additionally, an electric screw jack  48  could be used to raise and lower internal frame  30 . Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given.