Truck mounted elevating rack and method of unloading oversized items

Abstract

An overhead frame mounted on a truck. A stationary frame is supported by vertical legs mounted to the corners of the truck bed. An elevating frame of smaller proportions rests and nests within the stationary frame, and pivots on a bolt assembly that attaches to the stationary frame. The trailing end of the stationary frame incorporates a row of rollers. A corresponding set of rollers is attached to the rising end of the elevating frame. When the elevating frame rises by means of an electric winch, the load gradually comes into contact with the rollers and is discharged by gravity onto the ground from the rear of the stationary frame. The elevating frame incorporates adjustable arms to permit mounting on existing overhead truck racks of varying sizes.

1 . An apparatus that automatically discharges a load from the top of a truck comprising: 
 a stationary frame of rectangular shape having lateral members, a forward end, a trailing end, and one or more cross-members; said stationary frame being mounted to and positioned above the top of a truck by a plurality of vertical supports extending perpendicularly from predetermined locations on said truck;    an elevating frame of rectangular shape having two side members, a rising end and an opposing end, said elevating frame having outside dimensions smaller than the inside dimensions of said stationary frame, and rotatably attached to and within said stationary frame on an axis parallel to the axels of said truck; and    means for raising and lowering said elevating frame.    
   
   
       2 . The apparatus of  claim 1  wherein said rising end and said opposing end of said elevating frame are connected, perpendicularly, by one or more cross-braces.  
   
   
       3 . The apparatus of  claim 2  where the means for raising and lowering said elevating frame comprises: 
 a flange attached at the mid-point of one end of said elevating frame incorporating an attachment eye; and    means for controlled pulling upon said flange in a relative downward direction.    
   
   
       4 . The apparatus of  claim 3  where said means for controlled pulling is an electric winch and cable system where said cable is extendable from the reel of said winch and attachable to said attachment eye of said flange.  
   
   
       5 . The apparatus of  claim 4  further comprising: 
 means for reducing friction at a first point of contact where a load contacts said trailing end of said stationary frame; and    means for reducing friction at a second point of contact where a load contacts the rising end of said elevating frame.    
   
   
       6 . The apparatus of  claim 5  where said means for reducing friction at said first point of contact is a plurality of rear rollers permanently and linearly attached to said trailing end of said stationary frame.  
   
   
       7 . The apparatus of  claim 6  where said means for reducing friction at said second point of contact is a plurality of forward rollers permanently and linearly attached to said rising end of said elevating frame;  
   
   
       8 . The apparatus of  claim 7  further comprising guide brackets attached to said side members proximally to said rising end of said elevating frame.  
   
   
       9 . A kit for converting a standard truck rack into an apparatus that automatically discharges a load from the top of a truck comprising: 
 an open frame having one side member, a rising end and an opposing end, and a frame pivot bracket;    a frame extension having an extension side member, two or more insertion arms capable of insertion into the rising end and the opposing end of said open frame, and an extension pivot bracket corresponding to said frame pivot bracket on said open frame.    means for locking said insertion arms of said frame extension into said rising end and said opposing end of said open frame at variable positions thereby forming an adjustable elevating frame; and    means for raising and lowering said adjustable elevating frame.    
   
   
       10 . The kit of  claim 9  wherein said rising end and said opposing end of said adjustable elevating frame are connected, perpendicularly, by one or more cross-braces.  
   
   
       11 . The kit of  claim 10  wherein said means for raising and lowering said adjustable elevating frame comprises: 
 a flange attached at a predetermined position on the opposing end of said adjustable elevating frame and incorporating an attachment eye; and    means for controlled pulling upon said flange in a relative downward direction.    
   
   
       12 . The kit of  claim 11  wherein said controlled pulling means is an electric winch and cable system whereby said cable is extendable from the reel of said winch and attachable to said attachment eye of said flange.  
   
   
       13 . The kit of  claim 12  further comprising means for reducing friction at a point of contact where the rising end of said adjustable elevating frame contacts a load to be discharged.  
   
   
       14 . The kit of  claim 13  wherein said means for reducing friction at said point of contact is a plurality of forward rollers permanently attachable to said rising end of said adjustable elevating frame.  
   
   
       15 . The kit of  claim 14  further comprising guide brackets attached to said side member and said extension side member proximally to said rising end of said adjustable elevating frame.  
   
   
       16 . A method comprising the steps of: 
 constructing an elevating frame of rectangular shape having two side members, a rising end and an opposing end, said elevating frame having outside dimensions smaller than the inside dimensions of an existing stationary rack attached to and positioned above a truck;    rotatably attaching said elevating frame to and within said stationary existing rack on an axis parallel to the axels of said truck;    attaching means for raising and lowering said elevating frame;    
   
   
       17 . The method of  claim 16  wherein said means for raising and lowering said elevating frame comprises: 
 a flange attached at a predetermined position on the opposing end of said elevating frame and incorporating an attachment eye; and    means for controlled pulling upon said flange in a relative downward direction.    
   
   
       18 . The method of  claim 17  wherein said means for controlled pulling is an electric winch and cable system where said cable is extendable from the reel of said winch and attachable to said attachment eye of said flange.  
   
   
       19 . The method of  claim 18  further comprising application of means for reducing friction to the points where the load to be discharged contacts said rising end of said elevating frame and the trailing end of said existing stationary rack.