Abstract:
An automotive ladder and mounting assembly for use to access automotive compartments such as a truck bed or a horizontal deck is disclosed. The ladder can have a variety of features including extendable legs or wheels and a dolly platform for transporting items and may be detachable from the automobiles for use as a ladder or hand truck.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention relates to automotive ladders, including multi-function ladders useful for accessing an automotive bay such as a cargo bay or truck bed. 
       BACKGROUND 
       [0002]    Users of trucks and similar automobiles often carry cargo such as equipment, tools, and supplies. Easy access to and from the cargo area is desirable both for a person&#39;s convenience and safety. Some automobiles, including trucks, typically have a tailgate that can be opened to help access the cargo bed, however, even when open to the horizontal position, the tailgate is frequently too high off the ground to afford the convenience and safety desired by a user. In addition, equipment such as a dolly or hand cart to ferry equipment from the vehicle to a desired location would be useful if it can be easily stored or mounted on the vehicle and easy to use. 
         [0003]    While attempts to improve egress from cargo areas of vehicles have been made, there remains a need for improved access, particularly with equipment that can also be used for transporting cargo from the vehicle. For example, some ladders are formed as part of the tailgate, and thus cannot be removed from the tailgate or retrofit onto existing tailgates. Other conventional tailgate ladders are fixed to the inside of the tailgate. Some tailgate ladders are foldable with multiple pivot points which increase manufacturing cost. There is, therefore, a need for truck tailgate ladders that can be securely attached to any horizontal deck surface but still provide versatile and convenient use and be economical to manufacture. 
       SUMMARY 
       [0004]    In one aspect, a multi-function automotive ladder is disclosed having a frame having two stringers, each stringer having upper and lower ends; a plurality of steps extending between the stringers; a pair of handles, each handle having first and second ends, the first end of each handle being attached to the upper end of a corresponding stringer. 
         [0005]    In some embodiments, the each stringer of the ladder further comprises an upper stringer and a lower stringer, and the ladder also has two hinges, each hinge connecting an upper stringer to a lower stringer. In some embodiments, the hinges are located near a middle of the distance between the upper and lower ends of the stringers. 
         [0006]    In some embodiments, the stringers comprise rectangular tubing. In some embodiments, the ladder also has leg extensions. In some embodiments, the ladder also has a pair of wheels connected to the leg extensions and an axle. In some embodiments, the ladder also has adjustment holes for adjusting the position of the leg extensions. In some embodiments, the position of the leg extensions are adjusted and locked using an internal spring plunger that engages the adjustment holes. In some embodiments, the position of the leg extensions are adjusted and locked using an external spring plunger that engages the adjustment holes. 
         [0007]    In some embodiments, the ladder also has a platform removably connected to the lower ends of the stringers. In some embodiments, the platform is pivotally connected to the leg extensions so that the platform can swing between substantially parallel and substantially perpendicular orientations with the stringers. 
         [0008]    In some embodiments, the ladder assembly has a mounting bracket releasably attached to the second ends of the handles. In some embodiments, the ladder assembly has a connecting pin that secures a disc to the second end of the handles and a cleat receiver on the mounting bracket releasably engages the connecting pin. In some embodiments, the ladder assembly has a disc attached to the second end of the handles, and a disc receiver having a cleat bar attached to the mounting bracket, the disc releasably engaging the cleat bar. In some embodiments, the mounting bracket attaches to an automotive body or horizontal deck. 
         [0009]    In another aspect, a method of transporting cargo from an automobile includes providing an automotive ladder previously described and loading cargo onto the ladder. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a side view of a ladder assembly with extension legs and wheels. 
           [0011]      FIG. 2  is a side view of a ladder assembly with a platform and wheels in a folded configuration. 
           [0012]      FIG. 3  is a top view of a mounting assembly with a cleat plate and cleat receivers. 
           [0013]      FIG. 4  is a side view of a ladder assembly and mounting assembly connected to an automobile surface. 
           [0014]      FIG. 5  is side view of the ladder assembly of  FIG. 1 . 
           [0015]      FIG. 6  is a front view of the ladder assembly of  FIG. 2 . 
           [0016]      FIG. 7  is a side view of a cleat plate with two disc receivers mounted thereon. 
           [0017]      FIG. 8A  is a side view of a ladder assembly showing a handle with a disc and disc opening. 
           [0018]      FIG. 8B  is a side view of a ladder assembly showing a handle with a disc and disc opening. 
           [0019]      FIG. 9  is a side view of a ladder assembly showing a handle engaged with a mounting assembly. 
           [0020]      FIG. 10  is a side view of an extension leg with an attached wheel. 
           [0021]      FIG. 11  is a side view of an extension leg inserted into a ladder assembly and secured with a spring plunger. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. 
         [0023]    In one aspect, an automotive ladder assembly is disclosed. The assembly includes various components including a ladder with stringers, steps, a pair of handles, and a mounting assembly for connecting the ladder&#39;s handles to a horizontal deck such as a tailgate of a vehicle. 
         [0024]    Referring to  FIG. 1 , there is shown an embodiment of a ladder assembly  10 . The ladder assembly  10  includes a pair of parallel stringers  11 . In general, the stringers  11  are substantially parallel to one another. In some embodiments, each stringer may also include an upper segment  15  and a lower segment  17 . In some embodiments, the upper and lower segments can be connected through a hinging means, such as hinge assembly  16  shown in  FIG. 1 . The hinge assembly enables a user to fold the ladder assembly between an extended state (such as that shown in  FIG. 1 ) and a collapsed or folded state (such as that shown in  FIGS. 2 and 6 ). In the folded state, the stringer segments  11  form an angle of between 120 and 180 degrees. 
         [0025]    In some embodiments, the stringers need not be substantially parallel for their entire length relative to one another. For example, the lower segment of the stringers may be wider at their base and narrow as the lower stringers connect with the upper stringers. 
         [0026]    The hinge assembly  16  includes a hinge block  25  mounted on a rear side of a stringer  11 , such as a bottom portion of an upper stringer  15 . The hinge block  25  is configured to have an opening  61  to receive a hinge pin, and the hinge pin also passes through a stringer  11  providing for a pivot point in the ladder assembly. The hinge assembly  16  also includes a plate  27  which can be mounted on an upper portion of the lower stringer  17 . In some embodiments, the hinge plate  27  may integral with the lower portion  17 . In other embodiments, the hinge plate  27  can be welded to a lower portion of upper stringer. In some embodiments, the hinge plate  27  may be removably connected to the upper portion of the lower stringer  17 . The hinge plate  27  may also include a locking opening  65  through which a hinge pin  63  or a cotter pin  67  or other fastening device may pass. When in a locked configuration, the fastening device (e.g. cotter pin  67 ) passes through locking opening  65  and a corresponding locking opening  69  located near the lower portion  47  of the upper stringer  15 . 
         [0027]    Optionally, one of the upper and lower portions may have a storage opening in which the fastening device may be stored. For example in  FIGS. 1 and 2 , storage opening  55  may receive a cotter pin  67  when the ladder is in a folded configuration. 
         [0028]    In some embodiments, the parallel stringers  11  are continuous and incapable of folding. 
         [0029]    The ladder assembly  10  also includes a plurality of steps (or rungs)  13  spanning between the stringers  11 . The steps  13  can be perpendicular to the stringers  11  and connected, for example with a metal weld. The height of the stringers  11  and width of the steps  13  may be of varying dimensions with consideration of automobile height and width. In some embodiments such as those shown in  FIGS. 1 and 2 , the steps  13  are welded at their ends  30  to the stringers. In other embodiments, the parallel steps can fit into a plurality of pre-formed openings in the stringers  11 . 
         [0030]    In some embodiments, the steps  13  can be textured such as with a plurality of raised bumps or stippling  31 . In some embodiments, the texture can take the form of parallel grooves, intersecting grooves, and the like. The texture serves the purpose of improving the friction between a user&#39;s shoes or gloves with the steps, thereby giving improved traction when climbing up and down the steps. 
         [0031]    A pair of handles  12  having first ends  101  are mounted to the stringers at the upper portions  49  of the upper portions  15 . The handles  12  may be manipulated by a user when removing the ladder assembly  10  from an automobile or horizontal deck (not shown). The handles may include gaps  137  that facilitate a user&#39;s gripping of the handles. The handles  12  also can connect the ladder assembly  10  to a mounting assembly  71  through discs  99  mounted on the second ends  103  of the handles  12 . The discs  99  are attached to the handles with connecting pins  95  and leave a gap between the discs  99  and handles  12 . 
         [0032]    Referring now to  FIGS. 3 and 4 , a mounting assembly  71  for connecting the ladder to a vehicle surface is shown. The mounting assembly includes a cleat plate  73 . The cleat plate includes at least one or a plurality of openings  75  through which fasteners can attach the cleat plate  73  to an automobile surface  79  such as a tailgate. Fasteners include rivets, bolts, clamps, among others. In another embodiment, the cleat plate may attach to a horizontal surface with hook and pile fasteners. 
         [0033]    In some embodiments, the cleat plate  73  includes a pair of cleat receivers  81  which are connected to cleat plate  73 . The cleat receivers  81  may be pivotally connected with hinges  83 . The cleat receivers  81  include a channel  89  that extends from a first end  91  to nearly the center of the receiver  81 . The channel  89  has a width  96  corresponding to the diameter of connecting pins  95  located on handles  12 . 
         [0034]    In some embodiments, handles  12  connect to the cleat plate  73  by sliding the connecting pins  95  through the channel  89  to the center of the receiver  81  and alongside discs  99 . A locking strap  93  may be rotated forward about an axis of the connecting pins  95  to secure the handle connection to the plate  73 . 
         [0035]    In some embodiments such as shown in  FIGS. 5 and 10 , the lower portions  17  may include a plurality of holes  107  for aligning with extension legs  35  that fit within the lower portions  17 . The extension leg inserts may have wheels  37  (phenolic caster wheels for example) connected to a bottom end  41  of the extension leg through a wheel axle  39 . An upper end  43  of the extension leg fits within the lower portion  17 . The extension legs may be locked into the lower portion using, for example, an internal spring plunger  33 . The spring plunger  33  may be inserted into the holes  107  and a corresponding pair of holes  207  passing through the width (or a tube) of an extension leg. The spring plunger  33  may be pushed in to facilitate height adjustment. The spring plunger  33  becomes extended each time it aligns with an appropriate hole  107 . 
         [0036]    The height of extension legs  35  may be independently adjusted such as with spring plungers  105  to hold the extension legs  35  (with or without optional wheels) at a desired height. Such options may be desirable when the ladder might abut an uneven surface. The spring plungers  105  are inserted into holes  107  in the lower portions. Other appropriate fasteners can be used. 
         [0037]    In some embodiments such as shown in  FIG. 11 , an external spring plunger  34  may be inserted into holes  107  in the lower portions of stringers  11  to hold the extension leg  35  in the stringer  11 . 
         [0038]    Referring to  FIGS. 2 and 6 , there is shown the embodiment of  FIG. 1 , but with the ladder assembly  10  in a folded configuration and without connection to the mounting assembly  71 . Because the lower segments of the stringers can have insertable extension legs, a wide variety of features can be added to the bottom of the ladder. As also shown in  FIGS. 2 and 6 , the platform and wheels make the ladder usable as a dolly or moving truck. Other suitable equipment may also be added to the ladder so long as that equipment is fitted with extension legs that fit within the stringers. As shown in  FIG. 1 , the extension legs can be fitted with wheels. Alternatively, extension legs can simply extend the height of the ladder for use to climb other surfaces such as a wall. In such embodiments, the extension legs may also be bridged to one another with one or more steps. Also, because the extension legs are adjustable, the ladder may be used on uneven ground surfaces. 
         [0039]    Extendable arms may also be inserted in to the top of the stringers to provide additional grasping handles. The grasping handles can enable a user to steady themselves when the assembly is used as a ladder, or to extend the assembly when used as a dolly or hand truck. 
         [0040]    The stringers, steps, and other components of the ladder assembly may be made from a variety of materials, including metals such as steel or aluminum, or suitable, strong polymers. 
         [0041]    In some embodiments, the stringers can be made of rectangular tubing. In some embodiments, the stringers can be made of circular tubing. 
         [0042]    Referring to  FIGS. 2 and 6 , there is shown an alternate embodiment of the ladder assembly shown in  FIG. 1  where the lower ends  13  of the stringers  11  are connected to a platform assembly  131   
         [0043]    The platform assembly includes a platform  114  situated between extension legs  113 . The extension legs are receivable into the lower portions  17  of the ladder assembly. The extension legs also adjoin struts  115  which are connected to a wheel axle  117 . The wheel axle is connected to a pair of wheels  119 , (inflatable rubber wheels, for example). 
         [0044]    In some embodiments such as shown in  FIG. 7 , a cleat plate  173  has one or more openings  175  that can be connected to a vehicle surface by fasteners  177 . Fastener  177  can be anything that secures the cleat plate  173  to a vehicle surface, for example a rivet, screw, nail, or pin. The cleat plate  173  has one or more disc receivers  190 . Disc receiver  190  has a cleat bar  180  that is configured to receive a disc opening  170 , described below. As shown in  FIG. 8A and 8B , at least one disc  199  is secured to the second end  203  of handle  112  with at least one connector  150 . Connector  150  can be a bolt, nail, screw, or any suitable connector capable of securing the disc  199  to the end of the handle  112 . The disc  199  is shaped to have a disc opening  170  that is configured to engage mounting assembly  171 . The disc opening  170  may be any suitable shape that can engage the mounting assembly  171 , for example an oblong shape. The disc  199  has a locking bar  160  that is generally T-shaped, although it can be any shape that can secure the disc opening  170  to the mounting assembly  171  as described below. The locking bar  160  is configured to be in an engaging position—where the disc opening  170  is secured to the mounting assembly  171  as seen in  FIG. 9 , and a releasing position—where the locking bar  160  does not secure the disc opening  170  to the mounting assembly  171 . A user moves locking bar  160  through a locking bar channel  165  to move the locking bar  160  from an engaging position to a releasing position. 
         [0045]    Other systems, methods, features and advantages will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the following claims. The embodiments described below may be more fully understood by reading the following description in conjunction with the drawings.