Abstract:
An expandable rack for a truck bed used to transport lumber and the like is provided by a plurality of folding legs rigidly connected to an upper frame that supports the lumber. The folding legs allow the upper frame to retract completely within the truck bed compartment so as not to protrude over the edge of the truck bed side walls when not in use. Further, the configuration of the present invention provides an unobstructed truck bed in that no portion of the expandable rack except the folding legs occupy space on the truck bed floor, allowing the truck bed to be loaded without having to position the loaded materials over or around the rack. The present invention deploys easily to allow a single person to easily convert the rack from a retracted position to a deployed position.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to racks mountable on a vehicle&#39;s exterior, and more particularly to a rack adapted to secure to a pick-up truck bed for carrying lumber and other oversized materials. 
     2. Description of the Related Art 
     It is well known to provide a lumber rack for a pick-up truck to carry lumber, piping, wall boards, and a multitude of construction materials and other elongate objects. Many of the prior art racks are arranged in a fixed configuration so as to be permanently mounted above the truck bed. However, when the rack is not in use, it is usually desirable to retract the rack so that it is hidden inside the truck bed where it can be used in combination with a soft or hard truck bed cover. Accordingly, a number of prior art lumber racks retract when not in use by collapsing in one form or another. However, when retracted the lumber racks of the prior art typically rests on or across the truck bed, such as in a specially provided storage compartment on the truck bed floor, resting in its collapsed state on the floor of the truck bed, or seated on the top of the truck bed rails viewable from the side. Where the retracted lumber rack occupies a position across the floor of the truck bed then it may be very difficult to load a heavy object into the truck bed since the rack will be in the way. Moreover, if a special storage compartment is used then the amount of cargo space in the truck bed is diminished appreciably. Thus, when the rack is retracted into a hidden configuration it is desirable to maintain the truck bed clear of the rack or special storage compartments so that the bed may be used more efficiently for carrying other objects. 
     Also, it has been discovered by the present inventor that the use of telescoping members to extend and retract the rack can present reliability problems and cause premature wear. That is, the environment of the truck bed is such that dirt, sand, and other granular particles can be lodged between the telescoping members making it difficult to raise and lower the rack. If only one person is attempting to deploy the rack, the resistance in the telescoping poles due to the embedded particles can cause the rack to twist, bend, warp, and bind leading to possible eventual failure of the rack. Accordingly, a reliable deployment of the rack that is less susceptible to the introduction of sand or dirt is needed in the art. Finally, the ability of a lone person to easily and quickly deploy the rack without the rack bending or twisting is a feature not found among the prior art truck racks. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a truck rack that maintains an unobstructed path into and out of the truck bed when the rack is retracted in a hidden configuration. The hidden configuration preferably completely conceals the rack from view when the truck is viewed from the level of the truck bed side walls, and can be deployed from a hidden configuration to a deployed configuration easily and reliably by a single person. The truck rack of the present invention includes a reliable deployment mechanism comprising legs having rigid members connected by hinges that allow the rigid members to fold upon themselves rather than telescope. The folding leg members are preferably rigidly mounted to an upper frame that is concealed within the sides of the truck bed when the rack is retracted, and extends above the truck cabin when deployed. With the upper frame hidden within the sides of the truck bed in the retracted position, the floor of the truck bed is clear of the rack with the exception of the four legs located at each corner of the truck bed. The absence of any obstruction across the truck bed floor permits easy loading and unloading without the need to lift objects over the retracted rack. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The exact nature of this invention, as well as its objects and advantages, will become readily apparent upon reference to the following detailed description when considered in conjunction with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof, and wherein: 
     FIG. 1 is an elevated perspective view of a preferred embodiment of the present invention showing a truck bed with the extendable rack of the present invention in retracted mode; 
     FIG. 2 is an elevated perspective view of the preferred embodiment of the present invention of FIG. 1 showing the extendable rack in a partially deployed mode; 
     FIG. 3 is an elevated perspective view of the preferred embodiment of the present invention of FIG. 1 showing the extendable rack in a fully deployed mode; 
     FIGS. 4 and 5 are side views of the preferred embodiment of FIG. 1 showing the retracted mode (FIG. 4) and a partially deployed mode (FIG.  5 ); and 
     FIG. 6 is a close-up elevated perspective view of a preferred hinge mechanism for joining the rigid members of the legs. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the general principles of the present invention have been defined herein specifically to provide an extendable rack and frame for a pick-up truck bed. 
     FIGS. 1-3 illustrate a first preferred embodiment of the present invention providing an extendable rack adapted to be mounted to the back of a pick-up truck. The rack is preferably made of aluminum, but steel or other materials can be substituted without departing from the scope of the invention. For reference, the truck  100  comprises a truck cab  110 , a truck bed  120 , truck bed side walls  130 , a truck bed forward wall  140 , and a tail gate  150 . The elements of the truck  100  are well known in the art and form no part of the present invention. Mounted in the four corners of the truck bed  120  are folding legs  200  comprising three rigid elements  205  coupled together by hinges  210  that permit connected pairs of rigid elements  205  to fold with respect one another as shown in FIGS. 1 and 4. The bottom  215  of each folding leg  200  is mounted to the bed  120  of the truck  100  using a bracket  220  for support, where the bracket  220  is preferably fixed to the truck bed  120  floor using a welding operation, although other means for mounting the legs such as bolts or rivets can be substituted. Mounted on the top of each folding leg  200  is an upper frame  225  having longitudinal side beams  230  and traverse front and rear beams  240 ,  245  interconnected to form a rigid, orthogonal platform that constitutes the frame  225 . The frame  225  can support a variety of objects loaded thereon, especially lumber. 
     The longitudinal side beams  230  preferably include a plurality of spaced apart vertical ribs  260  connected at their respective upper ends by a horizontal bar  265  to form left and right guides  270  to the frame  225  as shown in FIGS. 1-3. The guides  270  are sized to keep the rack hidden within the truck bed compartment (i.e., below the truck bed side walls) when the rack is in the retracted position, but of sufficient height to provide a barrier for cargo loaded on the frame  225  in the deployed position. The guides preferably depend downward from the longitudinal rails in the retracted position so that the rigid segments  205  of the legs  200  can be made longer without the frame  225  extending over the truck bed compartment in the retracted position. The guides can be switched from the downward projecting position to the upward projecting position as shown in FIGS. 2 and 3 by fasteners that pass through holes in the longitudinal side beams  230 . Placing holes on the upper and lower surfaces allow the guide member positions to be interchangeable, such that a user can move the guide members to the upright position upon deploying the rack from its retracted position. 
     Nested within the longitudinal side beams  230  at each end is a front extension  280  and rear extension  290  to the frame  225 . The front extension  280  is constructed of left and right extending rods  305 ,  310  that nest into the longitudinal side beams  230  of the frame  225  when not in use, and project forward of the traverse front beam  240  to extend the frame  225  over the truck cab  110  (FIG.  3 ). The extending rods  305 ,  310  of the front extension  280  are connected at a distal end by a front cross bar  320 , extending the frame  225  to the front cross bar  320  in a common plane. Similarly, the rear extension  290  is constructed of left and right extending rods  330 ,  340  that also withdraw into the longitudinal side beams  230  at the aft end when not in use, and project rearward of the traverse rear beam  245  to extend the frame  225  beyond the back end of the truck bed  120  in a common plane. 
     In a preferred embodiment as shown in FIGS. 4 and 5, the juncture between the foldable legs  200  and the longitudinal side beams  230  is fortified by diagonal supports  350 . The supports  350  can be welded to the outside edges of the uppermost rigid segment  205  of the folding legs  200  and the frame  225  in a permanent arrangement so as not to cause interference with the folding operation. At the base of the folding legs  200  preferably are brackets  220  that mount the bottom of the folding legs  200  to the to the truck bed  120 . The brackets  220  comprise a flat horizontal base  222  that receives the bottom of the lowermost rigid element  205  of the folding legs  200  and a vertically projecting triangular wall  224  that is attached to the lowermost rigid member  205  of the folding leg  200  to provide added support and rigidity to the rack. 
     To allow the folding legs to function as described, a hinge assembly is provided as shown in FIG.  6 . The folding legs  200  are comprised of individual segments  205   a,b  of square tubing having a hollow interior and defining rigid members. For a pair of connected hollow rigid members shown, the lower connected hollow rigid member  205   a  includes a first open end  360  into which a solid square base  370  of a first hinge component  380  is fixed using a fastener (not shown) inserted into the aperture. Similarly, the upper connected hollow rigid member  205   b  includes a first open end into which a solid square base  375  of the second hinge component is fixed using a fastener (not shown) inserted into the aperture. The first hinge component includes a pair of spaced apart parallel plates  395  defining a channel  400  therebetween. Each plate  395  is substantially rectangular in profile with a circular projection  410  depending therefrom for sufficient strength about the shaft bearings. The shaft bearing through holes  420  includes a shaft (not shown) that facilitates rotation of the plates about the shaft. The second hinge component includes a middle plate  430  positioned to occupy the channel  400  when the first and second hinge components are brought into engagement with each other in a sandwiched configuration. The tolerances and spacing between the plates are preferably such that no relative rotation between the two hinge members can occur when the middle plate  430  is disposed between the two outer plates  410 . A pair of holes are provided in each plate, where a first hole is vertically and horizontally offset from the second hole. The holes  450  are aligned on each plate  410 ,  430  to provide a passage for a removable pin (not shown) in the first set of holes and a fixed shaft disposed in the second set of holes  420 . 
     With the removable pin disposed in the first set of holes  450  through the three plates and the shaft fixed in the second set of holes  420 , the juncture between the upper rigid member  205   b  and the lower rigid member  205   a  is fixed and locked in an end-to-end relationship. This configuration would be used when the rack is deployed and the folding legs  200  are completely extended as shown in FIG.  3 . However, if the removable pin is taken out of the first set of holes  450  then the upper rigid member  205   a  and lower rigid member  205   b  can pivot with respect to each other about the shaft. If the upper rigid member  205   b  is rotated one hundred eighty degrees with respect to the lower rigid member  205   a  the individual segments are disposed in a side-by-side arrangement and the required folding relationship is established for the present invention. 
     As can be seen in FIG. 5, the front two folding legs and the rear two folding legs rotate initially in a direction away from the truck cab  140  in unison as the rack is deployed or retracted. The rigid connection of the four folding legs  200  with the upper frame  225  precludes the separate legs  200  from opening in all but the same direction and at the same time. The positioning of the forward pair of folding legs  200  with the truck cab  140  and the truck bed side walls  130  precludes the folding legs  200  from opening sideways or forward, leaving only the unison folding of the folding legs in the rearward direction. Only with the tail gate  150  down can the rack be folded up or down as the rear folding leg members rotate rearward initially. Since all of the folding legs are connected to the frame  225  and raise and lower in unison, a single person can raise or lower the rack easily by grasping the frame  225  and rotating it upward or downward into position. 
     To deploy the frame from its retracted configuration, the removable pins are withdrawn from the folding legs  200  and the rigid members  205  are unfolded to an end-to-end configuration as shown in FIG.  3 . The removable pins are inserted into each hinge assembly to lock the folding legs  200  in the end-to-end arrangement. The tailgate  150  can be closed, and the front and rear extensions  280 ,  290  can be extracted from their nested position within the longitudinal side beams  230  to increase the usable area of the frame  225 . The right and left guides  270  provide barriers for lumber or other materials and prevent the lumber from slipping or twisting, as well as providing a suitable anchor for a tie-down strap or cable. The lumber or other cargo can be loaded onto the frame  225  and extensions  280 ,  290  if necessary. To retract the rack, the extensions  280 ,  290  are reinserted into the longitudinal side beams  230  and the removable pins are removed. With the tailgate  150  down, the frame  225  is lowered and rotated until the rigid members  205  are folded into a side-by-side relationship as shown in FIGS. 1 and 4. As can be seen in FIGS. 1 and 4, the rack is completely contained within the pick-up bed compartment between the pick-up bed side walls  140  and beneath the upper edge  142  of the pick-up bed side walls  140  to conceal the rack from view. Moreover, as can readily be appreciated the floor  120  of the pick-up bed is completely free of any obstruction from the rack in the retracted position, as only the four corners where the folding leg/bracket/truck bed interface are occupied by the rack. When loading the pick-up it is of significant importance that the rack not take up much space on the truck bed so that other materials may occupy the space, and the present invention achieves this object using the embodiment described above. 
     Those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.