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FIELD OF THE INVENTION  
       [0001]     This invention relates generally to track hoes and like machinery, and, in particular, to systems and methods for transporting bulk amounts of material using such machinery.  
       BACKGROUND OF THE INVENTION  
       [0002]     Track hoes and like machinery are often used for digging through hard soil, pavement, and the like. As a result, shovels are sized such that the hydraulics powering the shovel can apply sufficient force to drive a relatively small shovel through the soil or pavement. The articulated arm and hydraulics of the arm are therefore capable of carrying much more material than can be lifted with the shovel. In use, great inefficiencies arise as a shovel sized for penetrating soil is used to transport soil, broken pavement, and other materials into a container such as a dump truck or dumpster. The steps of scooping, lifting, and dumping the undersized shovel must be repeated an excessive number of times in order to load materials broken up by the shovel.  
         [0003]     It would therefore be an advancement in the art to provide a system and method for loading, lifting, and dumping large amounts of loose material using a track hoe that took greater advantage of the power and capability of the articulated arm and associated hydraulics of the track hoe.  
       SUMMARY OF THE INVENTION  
       [0004]     A hopper enabling a track hoe to scoop, transport, and unload large volumes of materials is disclosed. The hopper includes a tray defining a full-tray center of gravity. A lift handle and a dump handle are secured to the tray. The lift handle is connected to the tray closer to the full-tray center of gravity than the dump handle, with the full-tray center of gravity between the point of securement of the lift handle and the dump handle. The lift handle pivotally mounts to the tray and includes a cross bar extending transversely across the tray for gripping by the shovel and thumb of a track hoe. Stops engaged the lift handle and the tray to maintain the cross bar a minimum distance above the tray to facilitate gripping by the track hoe.  
         [0005]     In one embodiment, the tray includes a floor, first and second lateral walls and a rear wall. The lift handle pivotally secured to the first and second lateral walls by means of U-shaped members pinned to the lateral walls. Portions of the U-shaped members interfering with the first and second lateral walls serve as the stops.  
         [0006]     The hopper is filled by various methods, including pushing the hopper into a mound of material or scraping material onto the tray. The hopper is dumped by various methods including lifting upwardly on the dump handle, resting the tray on a wall or a portion of the track hoe such that it tips, or driving a front edge of the tray into a mound of material or other structure to cause tipping.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.  
         [0008]      FIG. 1  is a perspective view of a hopper, in accordance with an embodiment of the present invention;  
         [0009]      FIG. 2  is a side view of a hopper, in accordance with an embodiment of the present invention;  
         [0010]      FIG. 3A  is a rear view of a hopper, in accordance with an embodiment of the present invention;  
         [0011]      FIG. 3B  is a front view of a hopper, in accordance with an embodiment of the present invention;  
         [0012]      FIG. 4A  is a top view of a hopper, in accordance with an embodiment of the present invention;  
         [0013]      FIG. 4B  is a bottom view of a hopper, in accordance with an embodiment of the present invention;  
         [0014]      FIG. 5  is a side view of a track hoe and hopper illustrating a method of loading the hopper, in accordance with an embodiment of the present invention;  
         [0015]      FIG. 6  is a side view of a track hoe and hopper illustrating an alternate method of loading the hopper, in accordance with an embodiment of the present invention;  
         [0016]      FIG. 7  is a side view of a track hoe and hopper illustrating a method of carrying a loaded hopper, in accordance with an embodiment of the present invention;  
         [0017]      FIG. 8  is a side view of a track hoe and hopper illustrating a method of dumping the hopper, in accordance with an embodiment of the present invention;  
         [0018]      FIG. 9  is a side view of a track hoe and hopper illustrating an alternate method of dumping the hopper, in accordance with an embodiment of the present invention; and  
         [0019]      FIG. 10  is a side view of a track hoe and hopper illustrating another alternate method of dumping the hopper, in accordance with an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0020]     Referring to  FIGS. 1 through 4 B, a hopper  10  includes a tray  12 , a lift handle  14 , and a dump handle  16 . The lift handle  14  is gripped by the shovel and thumb of a track hoe in order to lift a filled hopper  10 . The dump handle  16  is also gripped by the shove and thumb of a track hoe in order to dump the hopper  10 .  
         [0021]     The lift handle  14  is typically pivotally mounted to the tray  12 . In the illustrated embodiment, the lift handle  14  includes a cross bar  18  and two side bars  20   a ,  20   b . The side bars  20   a ,  20   b  mount to the tray  12  by means of U-shaped members  22   a ,  22   b . The legs of the U-shaped members  22   a ,  22   b  are pinned to side walls  24   a ,  24   b  forming part of the tray  12 . In use, the U-shaped members  22   a ,  22   b  function as stops, interfering with the pivoting of the lift handle  14  such that the cross bar  18  is distanced from the tray  12  such that a portion of the shovel or thumb of a track hoe can be inserted between the cross bar and tray  12  in order to grip the cross bar  18 . One or more tethers  26   a ,  26   b  attach to either the cross bar  18  or side bars  20   a ,  20   b  to limit the rotation of the lift handle  14  away from the tray  12 . The tethers  26   a ,  26   b  may secure to a portion of the tray such as the lateral walls  24   a ,  24   b  or a rear wall  28 . The tethers  26   a ,  26   b  may be embodied as chains extending from the rear wall  28 .  
         [0022]     The dump handle  16  typically secures to the rear wall  28  of the tray  12 . In the illustrated embodiment the dump handle  16  is embodied as a flexible cable  30  secured at its ends to the rear wall  28 . Laterally extending knobs  32  may be formed on the tray  12  to facilitate manipulation of the tray  12  as it lays on the ground or other support surface. The knobs  32  may be part of a single bar extending along the entire rear wall  28 . The shovel of a track hoe is used to push or pull on the knobs  32  to rotate the tray  12 . Cap plates  34  may be formed on the knobs  32 . The cap plates  34  may be caught by the shovel of a track hoe to drag the tray  12  laterally.  
         [0023]     The tray  12  may have reinforcing members  36  positioned along the upper edges of the lateral walls  24   a ,  24   b  to stiffen the tray and prevent damage from impact with the track hoe or the contents of the hopper  10 . A plate  38  may also secure along the exposed edge of a floor  40  extending between the side walls  24   a ,  24   b  and the rear wall  28  to facilitated scraping up material and to resist deformation of the leading edge of the floor  40 .  
         [0024]     The lateral walls  24   a ,  24   b  taper from a maximum height near the rear wall  28  to a minimum height near the front edge of the floor  40 . The floor  40  is typically narrowest near the rear wall  28  and grows wider toward the front edge.  
         [0025]     A filled tray  12  has a filled center of gravity  42 . In one embodiment the lift handle  14  is pivotable such that the cross bar  18  is substantially directly above the filled center of gravity  42 . The lift handle  14  typically secures to the tray  12  at a point of securement  44  such that the filled center of gravity  42  is positioned between the point of securement  44  and the point of securement of the tethers  26   a ,  26   b  to the tray  12 , such as the rear wall  28 .  
         [0026]     Referring to  FIG. 5 , in one method of loading the hopper  10 , the hopper  10  is placed in front of a mound  46  of material. A track hoe  48  then pushes the hopper  10  into the mound  46 . Many track hoes are provided with a long blade  50  extending along the front of the track hoe near the ground. The blade  50  may therefore be used to drive the hopper  10  into the mound  46 . Referring to  FIG. 6 , in an alternative method of use, the hopper  10  is placed near the mound  46  and the articulated shovel  52  is used to scrape material into the hopper  10 . The hopper  10  may be held in place by the blade  50  when using such a method.  
         [0027]     The methods of  FIG. 5  and  6  made possible by the hopper  10  decreases the amount of movement required by the articulated shovel  52  to scoop up material. Both hopper  10  and material may be located at ground level near one another. Only a single step of lifting and dumping is required to dump the filled hopper, rather than the repeated scooping, lifting, and dumping steps required to load an equivalent volume using the articulated shovel  52  alone.  
         [0028]     Referring to  FIG. 7 , to lift the hopper  10 , the lift handle  14  is gripped by capturing the cross bar  18  between the shovel  52  and thumb  54  of the track hoe  48 . The hopper  10  is then transported to a different location and dumped. In the method of  FIG. 8 , the shovel  52  and thumb  54  grip the dump handle  16  and lift upwardly to dump the hopper  10 . In the method of  FIG. 8 , the underside of the tray  12  proximate the rear wall  28  is lowered onto a structure, such as a side wall  56  of a truck. As the hopper  10  is lowered further it tips and dumps its contents. In a specific embodiment of this method shown in  FIG. 9 , the tray  12  is rested on the top of the blade  50  to cause the hopper  10  to tip. The track hoe  48  may be driven forward or back during dumping according to this method in order to distribute the contents of the hopper  10 . Gravel or other paving material may be distributed as it is driven over by the track hoe  48  in order to pave a road. The blade  50  may be used in this method to simultaneously distribute the contents of the hopper  10  evenly over the road. Other methods may also be used to tip the hopper  10 , including driving the front edge of the tray against a mound of already dumped material or other structure to cause tipping.  
         [0029]     While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.

Summary:
A hopper includes a tray having a floor, first and second lateral walls, and a rear wall. A lift handle pivotally secures to the lateral walls. A dump handle secures to the rear wall. The lift handle includes a cross bar extending transversely across the tray for gripping by the shovel and thumb of a track hoe. Stops engage the lift handle and the tray to maintain the cross bar a minimum distance above the tray to facilitate gripping by the track hoe.