Abstract:
A vehicle tailgate extension apparatus and method of using the same. The tailgate extension apparatus generally includes a U-frame member, a plurality of hinge elements, and a plurality of side braces. The U-frame member may be locked into a plurality of operative positions optionally including a backstop position, an extension position, and a step position. The extension apparatus is stored within the interior of the tailgate until needed, and the extension may be pulled out of the tailgate via a plurality of storage channels. The side braces directly connect the U-frame member to the vehicle tailgate and may be stored within the arms of the U-frame when the extension apparatus is stowed in the tailgate.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This patent application is a continuation in part application claiming priority from Unites States Patent Application: Tailgate Extension Apparatus, Ser. No. 10/167,767 filed on Jun. 11, 2002 now abandoned. 

   FIELD OF THE INVENTION 
   The present invention relates to tailgates for vehicles, and, in particular, it relates to extensions for tailgates which facilitate the carrying of certain types of cargo, or entry into the cargo space. 
   BACKGROUND OF THE INVENTION 
   As seen in  FIG. 1 , vehicles  20  such as pick-up trucks, station wagons, sport utility vehicles (SUVs), or other vehicles have cargo spaces  40  that are used for hauling materials. Such a vehicle, typically, has a tailgate  100  that serves as a barrier, thereby retaining the cargo within the bed. Many of these tailgates  100  are hingedly attached to the bed or vehicle frame at the lower portion of the tailgate, and the tailgate  100  can function in a vertical, locked position or a horizontal, open position. 
   Oftentimes, however, it is necessary to transport items that do not fit within the standard cargo space available when the tailgate is locked in a vertical position. This problem has been exacerbated in recent years by the influx of smaller vehicles on the automotive market. As such, a user is required to transport the cargo with the tailgate in an open horizontal position or with the cargo extending beyond the upper edge of a vertical tailgate. In either case, the user is required to take additional steps to manually secure the cargo in the bed. These additional steps may be time-intensive and prone to failure, resulting in the cargo accidentally falling out of the vehicle or becoming damaged. 
   Another difficulty frequently encountered when using conventional tailgates concerns entry/exit into and out of the cargo space or truck bed. Although it is desirable to access the inside of a truck bed, conventional open tailgates are too high to be used as a step, especially for people of a lower stature or people carrying items in their arms. As a result, access to cargo beds is often limited since most users cannot step from the ground directly into the cargo bed. 
   Thus a common problem with conventional tailgates is that they have inherent size limitations, both because the length of the bed is too short and because the tailgate is situated too far above the ground. As a result, extension devices for tailgates have been proposed, albeit often to address only one of the aforementioned problems. Many of the prior extension devices include pieces that are removably attached to the tailgate or, though permanently attached, are located external to the tailgate itself. Although such devices may be useful, they are frequently cumbersome and are not practical for everyday use since they require time-consuming setup procedures. Also, existing tailgate extensions and step devices may be stored externally when not in use. Such external storage ultimately takes up a portion of the existing bed space and can also be unsightly. Furthermore, conventional tailgate extensions do not attempt to combine the tailgate extensions and stepping devices into one, easily manipulated and stored unit. 
   Thus, there presently exists a need for a combination extension/stepping device that is easy to use, can be compactly stored, is convenient for the user to access, and can be readily set up to extend the working area of a bed and/or to create a step to enhance access to the bed. 
   INTRODUCTION TO THE INVENTION 
   One presently preferred embodiment of the invention provides a tailgate extension apparatus capable of performing as a backstop, a tailgate extension, and/or a step for use with a conventional cargo area in a vehicle. The tailgate extension generally comprises: a U-frame member including side arms and a step; two side braces; and two hinges. The side braces selectively connect the U-frame member directly to the vehicle tailgate. The hinges allow for rotation of the U-frame member such that the aforementioned positions (backstop, extension, and step) may be realized. 
   In at least one preferred embodiment, the tailgate extension apparatus may be stored within the vehicle tailgate and may be extendable by way of a plurality of channels located within the tailgate. These channels are preferably facilitated through the use of a hybrid tailgate that includes a metal skin wrapped around a plastic reinforcing module. 
   The side arms of the U-frame member, preferably, contain recesses in which the braces may be stored when the extension member is in its stored position inside the vehicle tailgate. In this way, the U-frame member, the braces, and the hinges may all be stored within the tailgate and are not visible from the outside of the vehicle, and are not stored in the cargo space of the vehicle. 
   The invention also comprises methods for removing and locking the tailgate extension apparatus into various useful positions. To use the tailgate extension apparatus, the user may unlatch and lower the vehicle tailgate, release and extend the U-frame member, and rotate and lock the U-frame member into a final usable position. The side braces may be removed from the tailgate extension apparatus by extracting the braces laterally from the side recesses of the arms of the U-frame member. These side braces may then be used to lock the extension at an appropriate angle to the tailgate using conventional tailgate latches. Preferably, the tailgate extension apparatus may be locked in various positions to create a backstop, extension or step. 
   It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. 
   SUMMARY OF THE INVENTION 
   The present invention is an extension apparatus for a vehicle tailgate. It includes a U-frame member, which is slidingly extendable from an interior portion of the vehicle tailgate; and it also includes a plurality of side braces adapted to lock said U-frame member in a plurality of operative positions. 
   In another aspect, the present invention is a method for utilizing a tailgate extension apparatus. The method includes the steps of opening a vehicle tailgate into a substantially horizontal position, extending a U-frame member from a storage position within said tailgate to a position outside of the tailgate; and locking said U-frame member into one of three operative positions by means of two side braces which accommodate all positions. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For the present invention to be clearly understood and readily practiced, the present invention will be described in conjunction with the following figures, wherein like reference characters designate the same or similar elements, which figures are incorporated into and constitute a part of the specification, wherein: 
       FIG. 1  is a schematic view of a pickup truck from the rear with the tailgate in a locked vertical position; 
       FIG. 2  is a schematic view of the tailgate extension apparatus stored within a tailgate which is in the open position; 
       FIG. 3  is a schematic view of the tailgate extension apparatus pulled out from within the tailgate with hinges attached thereto and with side braces shown hanging from the sidearms of the tailgate extension apparatus; 
       FIG. 4  is a schematic top view of the tailgate extension showing side braces stored within the side arms of the tailgate extension. 
       FIG. 5  is a schematic showing the non-rotating portion of a hinge including a depression for engaging a detent; 
       FIG. 6  is a schematic view of the tailgate extension apparatus in the extension position; 
       FIG. 7  is a schematic view of the tailgate extension apparatus in the backstop position; 
       FIG. 8  is a schematic view of the tailgate extension apparatus in the step position; 
       FIG. 9  is a schematic cross section showing a channel in the reinforcing module, the channel being for a sidearm of the tailgate extension; 
       FIG. 10  is a schematic cross section showing a wire from the tailgate handle to one of the tailgate latches; 
       FIG. 11  is a schematic showing the tailgate extension in the backstop position and an optional cover plate; 
       FIG. 12  is a schematic cross section of the step portion of the tailgate extension, indicated as  12 — 12  in  FIG. 8 , the step portion having a knurled surface; and 
       FIG. 13  is a schematic cross section of the step portion of the tailgate extension, similar to  FIG. 12 , the step portion having a pad. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   It is to be understood that the figures and descriptions of the present invention have been simplified to illustrate elements that are relevant for a clear understanding of the invention, while eliminating, for purposes of clarity, other elements that may be well known. Those of ordinary skill in the art will recognize that other elements are desirable and/or required in order to implement the present invention. However, because such elements are well known in the art, and because they do not facilitate a better understanding of the present invention, a discussion of such elements is not provided herein. The detailed description will be provided hereinbelow with reference to the attached drawings. 
   In accordance with the present invention, a tailgate extension apparatus is provided that is capable of functioning in conjunction with a conventional tailgate ( FIG. 1 ) to add the functionality of three additional positions ( FIGS. 6 ,  7 , and  8 ). Initially referring to  FIG. 1  of the drawings, a tailgate extension apparatus is incorporated in a vehicle  20  with a drop down tailgate  100 . Handle  110  is for releasing latches (discussed later) which enable tailgate  100  to drop down to a horizontal position. Although the vehicle  20  shown in  FIG. 1  is a pick-up truck, the invention may be used with many different kinds of cargo-carrying vehicles. The tailgate  100  is preferably a hybrid tailgate (described below) comprised of a plastic inner structural module (reinforcing module) surrounded by a thin metal skin, but the present invention may also be used with a conventional hollow steel tailgate. When in its  FIG. 1  stored position, the tailgate extension apparatus can not be seen, except along the top edge of the tailgate  100 . 
     FIG. 2  schematically illustrates the tailgate  100  in its horizontal position, and  FIG. 3  shows the tailgate extension apparatus  200  pulled out from its storage position inside tailgate  100 . The tailgate extension apparatus  200  generally comprises: two side arms  282 , a step portion  280 , two side braces  310  that are removably attached to the side arms  282 , and a plurality of hinges having non-rotating portions  250  and rotating portions  286 . These are for enabling pivoting of the extended tailgate extension apparatus  200  between a plurality of operative positions. All of these components of the tailgate extension apparatus  200  are retractably mounted within the tailgate  100 , as indicated by dotted lines in  FIG. 2 . The operative positions preferably include a tailgate extension position ( FIG. 6 ), a tailgate backstop position ( FIG. 7 ) and a step position ( FIG. 8 ). 
   Preferably, the sidearms  282  and step  280  of tailgate extension apparatus  200  are integrally formed as a U-frame member  205 . Preferably, U-frame member  205  is formed of of extruded metal tubing, preferably aluminum or steel, but it could, alternatively, be made of a plastic, composite, or other material. Lighter materials are preferred to limit the overall weight of the tailgate and increase the ease with which the tailgate may be used. 
     FIG. 4  is a top view of the U-frame member  205  showing how side braces  310  are stored when the tailgate extension apparatus  200  is stored within tailgagte  100 . The two side arms  282  of the tailgate extension  200  preferably include storage recesses  350  into which the side braces  310  may be stored when the tailgate extension apparatus  200  in not in use. The recesses  350  are in the outwardly facing sides of the side arms  282 . Each recess  350  preferably also includes a hole  360  (best seen in  FIG. 3 ) through which the locking post  320  of side brace  310  may be inserted. Each recess preferably also includes a hole  365  for the offset portion  330  of the side brace  310 . A through hole  370  in the inwardly facing sides of the side arms  282  is also provided for the offset portion  330  of the side brace  310 . 
   Preferably, a threaded mechanical fastener  340 , such as a cap screw, selectively prevents the side brace  310  from disengaging completely from the side arm  282 . The side brace  310  may be retained in its storage position by a clip or other fastening device (not shown) that functions to hold the brace  310  in place yet also releases it from the sidearm  282  when adequate lateral pressure is applied to the brace. 
   The U-frame member  205 , preferably, has various cross-sections at different parts (such as rectangular, round, oval or otherwise shaped in profile), with the appropriate cross-section profile being chosen for the purpose that any particular area of the member is intended to serve. 
   In a presently preferred embodiment, the U-frame member  205  is a hollow extruded aluminum tube that has a circular or oval profile upon extrusion. The tube may then be hydroformed to impute the angles necessary to create the step  280 , the recesses  350  for the side braces  310 , and other features. The step  280  itself may have a more “flattened” profile such as an oval or “C” shape so that the upper portion of the step (when the U-frame  205  is in the step position) provides a broad, flat surface area upon which a user can step. In additional embodiments, the various segments (e.g.,  280 ,  282 ) of the U-frame member  205  may be manufactured separately, and then brought together before being installed into the tailgate. Many different variations on this theme are envisioned within the scope of the invention. 
   The tailgate  100  preferably includes two hollow slots or channels  170  that serve to house and guide the arms  282  of the tailgate extension  200 .  FIG. 3  defines two sections,  9 — 9  and  10 — 10 . The former section is shown in  FIG. 9  and the latter is shown in  FIG. 10 . Channels  170 , which are visible in  FIGS. 9 and 10  guide the tailgate extension  200  to move from its its stored position ( FIG. 2 ) to its extended (operative) positions ( FIGS. 6 ,  7 , and  8 ). 
   Referring to  FIGS. 9 and 10 , the inner portion  172  of channel  170  is provided to accommodate the offset portion  330  of side brace  310  as the tailgate extension  200  is moved between its stored position, as shown in  FIG. 2  to its extended position, as shown in  FIG. 3 .  FIGS. 9 and 10  show the structure of the hybrid tailgate. The upper metal skin  190  and the lower metal skin  195  are shown, above and below the reinforcing module  175 , respectively. 
     FIG. 10  shows a wire  186  which connects the tailgate handle  110  to one of the tailgate latches  180 . A similar wire (not shown) connects the tailgate handle  110  to the opposito latch. The latches  180  capture posts on the vehicle  20  when the tailgate is in the raised position shown in  FIG. 1 . Release of the latches  180  permits the tailgate to be lowered to the position shown in  FIGS. 2 and 3 . Following conventional practice, the latches  180 , preferably, are spring loaded to the closed position. When handle  110  is pulled, opening forces are applied to the latches  180  through wires  186 . Wires  186  pass through transverse slots  176  in reinforcing module  175 . 
   The present invention is preferably incorporated into a so-called “hybrid” tailgate but may also be used with an adapted conventional tailgate. A conventional tailgate is typically manufactured by forming a flat sheet of steel into the shape of a tailgate and thereafter welding the edges together. These tailgates are heavy to work with, and alternative solutions are continually sought. 
   A hybrid tailgate, on the other hand, includes an interior reinforcing module of plastic or other lightweight material that is formed as the framework of the tailgate. A thin sheet of metal, such as aluminum, is then assembled around the outside of this reinforcing member. The plastic/aluminum (or other) combination may be as strong as a conventional steel tailgate but is lighter and easier to work with. The general structure of a hybrid tailgate is disclosed, for example, in U.S. Pat. No. 5,944,373 which issued on Aug. 31, 1999, and which is incorporated herein by reference in its entirety. 
   With a conventional tailgate, the channels  170  that guide and store the arms  282  of the U-frame member  205  may have to be specifically formed within the tailgate. With the preferred hybrid tailgate, however, the channels  170  may be made by hollowing out part of the plastic reinforcing member that makes up the interior of the hybrid tailgate structure. Because the plastic reinforcing member already exists within the hybrid tailgate and further because plastic is an easier material to shape (mold) than steel, creating the channels  170  in the hybrid tailgate is preferred. 
   As best shown in  FIGS. 4 and 5 , hinge elements having non-rotating portions  250  and rotating portions  286  are preferably positioned on the ends of the U-frame arms  282  and serve to pivotably mount the tailgate extension  200  to the vehicle tailgate  100 . Each hinge non-rotating portion  250  includes a depression  253 . The depression  253  serves to lock the U-frame member  205  into a closed position for storage by way of a spring-loaded detent  156  within the tailgate. 
   Each hinge non-rotating portion  250  preferably includes a pair of pin engaging portions  252 . A pin (not shown) attaches the hinge rotating portion  286  to the hinge non-rotating portion  250 . Relative rotation occurs about axis  251  of the hinge non-rotating portion  250 . Such a design allows the U-frame member  205  to rotate almost 180 degrees about the non-rotating portion  250  when the U-frame member  205  is fully extended from the tailgate  100 . Thus, the U-frame member can be moved from the step position ( FIG. 8 ) to the extension position ( FIG. 6 ) or to the backstop position ( FIG. 7 ). 
   A spring-loaded detent  156  (shown schematically as a hidden block in the drawings) is located adjacent each channel  170 . The spring loaded detent  156  engages depression  253  on hinge non-rotating portion  250  to retain the tailgate extension  200  in the stored position inside the tailgate ( FIG. 2 ). 
   Additionally, there is a stop  158  (shown schematically as a hidden block in the drawings). Preferably, stop  158  engages the hinge non-rotating portion  250  to prevent the tailgate extension from being completely removed from the tailgate  100 . The stop  158  may, for example only, operate by engaging depression  253  on hinge non-rotating portion  250 . 
   The locking posts  320  on the side braces  310  are for engaging the tailgate latches  180  (schematically indicated in block form in the drawings). When the tailgate extension  200  is in the backstop position, shown in  FIG. 7 , or the step position, shown in  FIG. 8 , and the locking posts  320  on the side braces  310  are engaged with the tailgate latches  180 , the side braces  310  become diagonal braces which provide rigid positioning of the tailgate extension  200 . Rigid positioning of the tailgate extension  200  in the backstop position shown in  FIG. 7  and the step position shown in  FIG. 8  involves cooperation of the braces  310  and the stops  158 . 
   To realize the step position, the tailgate  100  is first opened by moving it from a vertical position ( FIG. 1 ) to a horizontal position ( FIG. 2 ). The U-frame member  205  is then disengaged from the stored position by disengaging the detent  156  (by pressing a release button and/or pulling the U-frame out of the tailgate  100 ) and extending the U-frame from the tailgate until the stop  158  engages the hinge non-rotating portion  250 . The braces  310  may then be released from the arms  282  of the U-frame member  205 . This may be accomplished by withdrawing each brace  310  laterally from a clip in the side of the U-frame member  205 . The U-frame member  205  may then be pivoted downward until it is possible to engage the locking posts  320  located on the side braces  310  with the tailgate latches  180  located on the sides of the tailgate  100 . 
   At this point the U-frame  205  is locked in position, and the U-frame can be used as a step ( FIG. 8 ). In one embodiment of the invention, the step portion  280  of the U-frame member  205  is grooved or knurled in a manner such that traction will be enhanced.  FIG. 8  shows the tailgate extension  200  in the step position, and defines a cross section,  12 — 12 .  FIG. 12  shows this cross section, and it shows the knurled surface  290  of the step  280 . In another embodiment, shown in  FIG. 13 , a pad  295  may be applied to the step  280  to aid in user traction. 
   To release the U-frame member  205  from this step position, the braces  310  are disengaged from the tailgate latches  180 , preferentially, by pulling the handle  110  on the tailgate  100  and pulling in an upward direction on the side braces  310 . The side braces  310  may then be placed in their storage positions in the recesses  350  in the arms  282  of the U-frame member  205 . The U-frame member  205  may then be returned to a horizontal position and reinserted into the tailgate by and sliding the U-frame member  205  into the tailgate until the detent  156  engages. 
   Another potential use of the invention is when the U-frame member  205  is in the tailgate extension position ( FIG. 6 ). This position allows for the hauling of oversized loads, much like a flatbed truck, but with more support for the cargo than with a conventional tailgate. In this position, the U-frame member  205  is extended horizontally from an open tailgate  100 , thereby increasing the effective length of the tailgate. 
   To realize this position, the tailgate  100  is first opened by moving it from a vertical position ( FIG. 1 ) to a horizontal position ( FIG. 2 ). The U-frame member  205  is then disengaged from the stored position by disengaging the detents  156  and extending the U-frame from the tailgate  100  until the locking posts  320  on the side braces  310  can be captured by the tailgate latches  180 , as shown. In this position, the side braces  310  are substantially parallel to the arms  282  of the U-frame  205 , and the side braces  310  prevent the tailgate extension  200  from being pulled fully out, so the channels  170  in the reinforcing module  175  prevent the U-frame member  205  from rotating downward. 
   At this point, the U-frame member  205  is locked in position and the U-frame can function as an extension of the existing tailgate  100  ( FIG. 6 ). To release the U-frame member  205  from this position, the braces  310  are removed from the latch mechanism  242  in the tailgate by pulling the handle  110  on the tailgate  100 . They are then replaced in their storage positions, within the recesses  350  of the U-frame arms  282 . The U-frame member  205  may then be reinserted into the tailgate  100  by sliding it into the tailgate until the detent  156  engages. 
   The present invention may also be used with the U-frame member  205  in the backstop position ( FIG. 7 ). This position allows for the hauling of oversized loads that may potentially fall out of the bed when the tailgater  100  is in a horizontal position. 
   To place the U-frame member  205  in the backstop position, the tailgate  100  is first opened by moving it from a vertical position ( FIG. 1 ) to a horizontal position ( FIG. 2 ). The tailgate extension  200  is then pulled fully out until the stops  158  prevent further movement. This is the configuration shown in  FIG. 3 . The U-frame member  205  is then rotated upwardly to the vertical position shown in  FIG. 7 . The side braces  310  are then attached by inserting the locking posts  320  into the tailgate latches  180 . In that configuration, the side braces  310  act as diagonal braces which prevent rotation of the U-frame member. The U-frame member  205  then acts as a backstop, preventing the accidental discharge of loads. Cargo may be lashed to the U-frame member  205 . 
   To release the U-frame member  205  from this position, the braces  310  are removed from the tailgate latch mechanism  180  in the tailgate  100  and replaced in their storage positions in the side arms  282  of the U-frame. The U-frame member  205  may then be returned to a horizontal position and reinserted into the tailgate  100  by sliding the U-frame into the tailgate until the detent  156  engages. 
   In order for the side braces  310  to place the U-frame member  205  in a vertical position for use as a backstop, or a slanting position for use as a step, the hole  365  for the offset portion  330  of side brace  310  may be placed below the axis of rotation  251  of the hinge non-rotating portion  250 . Also, the tailgagte latch  180  is preferably designed so that when locking post  320  is engaged with the latch, the locking post  320  is also below axis of rotation  251 . 
   Although the above description details the general structure and use of the present invention, there may also be additional features that can be used with the tailgate extension apparatus. For example, when the tailgate extension is used in the backstop or extension position, the extension is acting as a body panel but only comprises a U-frame. Therefore, there is a large amount of space within the U-frame through which certain types of cargo could fall out of the vehicle. 
   Therefore, as shown in  FIG. 11 , one preferred addition to the above tailgate extension apparatus includes a removable cover plate  400  that can be snapped or otherwise attached to the U-frame when necessary. The cover plate  400  may be a thin sheet of plastic, metal, leather, or any other suitable material. Preferably, the additional cover plate  400  is a thin solid sheet that can be attached to the surface of the tailgate that faces the interior of the truck bed or other cargo space. The plate  400  may be attached with a plurality of snaps, bolts, or any other fasteners. When needed, the plate  400  is simply removed from the tailgate and attached to the U-frame member. Once attached, the plate  400  will provide the support of a regular body panel. 
   It is preferred that the cover plate  400  be attached by hinges  410  to the conventional tailgate at the upper portion of the interior face of the tailgate. When the tailgate is opened and the tailgate extension apparatus is extended and locked into place as a backstop or extension, this additional plate  400  can be rotated on the hinges and swung against the U-frame which will be at a 90 degree (backstop) or 180 degree (extension) orientation from the open tailgate. Once swung into position, the cover plate  400  can be secured to the U-frame  205  with snaps or any other fastening mechanism. It is noted that cover plate  400  is not stored within the tailgate  100 , but lies against the top surface of the tailgate when the tailgate is down, which is the inner surface of the tailgate when the tailgate is up. 
   When the tailgate extension  200  is employed as a step, the cover plate  400  may be rotated to a position on the tailgate  100  so it does not interfere with step  280 . 
   Nothing in the above description is meant to limit the present invention to any specific materials, geometry, or orientation of elements. Many part/orientation substitutions are contemplated within the scope of the present invention and will be apparent to those skilled in the art. The embodiments described herein were presented by way of example only and should not be used to limit the scope of the invention. 
   Although the invention has been described in terms of particular embodiments in an application, one of ordinary skill in the art, in light of the teachings herein, can generate additional embodiments and modifications without departing from the spirit of, or exceeding the scope of, the claimed invention. Accordingly, it is understood that the drawings and the descriptions herein are proffered only to facilitate comprehension of the invention and should not be construed to limit the scope thereof.