Abstract:
A removable and attachable debris guard for a back wall of a loader bucket or a bulldozer blade is provided with a frame that is a generally inverted U-shape with outwardly tapering side legs, and has a strong mesh screen supported on the frame. The frame includes a cross plate that extends rearwardly of the mesh screen and has attachment hooks for fitting over a top rail of a back wall of a loader bucket. The frame includes brackets for securing the legs to a forward side of the back wall.

Description:
BACKGROUND OF THE DISCLOSURE 
       [0001]    The present invention relates to a debris guard that extends the height of the back wall of a bucket for a loader and which can be quickly installed to prevent rocks or other materials that might damage hydraulic components, lines and the like, from falling rearwardly. The debris guard is positioned in the center portions of the rear wall of the bucket during lifting, and can be easily removed when not needed. 
         [0002]    Loader buckets and bulldozer blades with fixed upright extensions on the back wall have been used. These generally are inconvenient in most applications. In addition, many of the extensions that are presently known restrict visibility forwardly to see what is being scooped into the bucket or pushed with a bulldozer blade, so that the operator&#39;s view is restricted. 
       SUMMARY OF THE DISCLOSURE 
       [0003]    The present disclosure provides a debris guard that can be quickly and easily attached to an upright wall of a bucket or to a dozer blade, and project upwardly from the normal height of the wall of the bucket, or from the blade. The debris guard of the present disclosure has a frame around a large size screen that will not substantially obstruct forward vision, but yet will have sufficient strength to resist impact from rocks that are in the bucket. The debris guard is effective when a bucket is tilted backwardly toward the operator and raised for dumping. 
         [0004]    The debris guard is inclined forwardly from the upright wall of a bucket to which it is attached, so the bucket capacity remains about the same as when the debris guard is not used. Thus even though the debris guard extends above the top of the back wall, the bucket can not be overloaded. Additionally the attachment brackets for the debris guard do not obstruct the operators steps that are on the bucket back wall for use in stepping to the front entry operator&#39;s seat or cab. 
         [0005]    The backstop or guard of the present disclosure catches rocks or large pieces of debris that may otherwise fall over the rear wall of the bucket onto hydraulic components, lines and controls that are used for controlling the bucket and also stops large rocks and debris from falling onto an operator or onto and operator&#39;s cab of the loader. Any debris that does fall though, has to pass through the openings of the debris guard. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic view of a typical loader having a bucket attached thereto with a debris guard of the present disclosure installed; 
           [0007]      FIG. 2  is a rear perspective view of a bucket removed from the loader with the debris guard of the present disclosure installed; 
           [0008]      FIG. 3  is front view of the bucket and debris guard of  FIG. 2 ; 
           [0009]      FIG. 4  is a top view of the bucket of  FIG. 3 ; 
           [0010]      FIG. 5  is a sectional view taken as on line  5 - 5  in  FIG. 3 ; 
           [0011]      FIG. 6  is an enlarged view taken substantially on the same line as  FIG. 5  to show the detail of a mounting attachment hook on the top rail of the bucket; and 
           [0012]      FIG. 7  is a rear perspective view of the present debris guard when removed from a bucket. 
       
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0013]    Referring to  FIG. 1 , compact tool carrier comprising a compact loader  10  is illustrated. This is an exemplary showing of a typical loader with which the present debris guard finds usefulness. The tool carrier or loader  10  has a transmission case or frame  12  having drive components for wheels  14  for movement across the ground. The loader includes a lift arm assembly  16 , which has lift arms on opposite sides of the loader frame, and the lift arms are raisable and lowerable using a hydraulic actuator  18  for pivoting the lift arm assembly about pivots  20 , between raised and lowered positions in a normal manner. As shown, the forward ends of the lift arms indicated at  22  have a tilting attachment plate  24  pivotally mounted at  26  to the forward ends of the lift arms. Tilting of the attachment plate  24  is controlled by a tilt cylinder  28  operated through suitable valves. The tilt cylinder  28  is a hydraulic cylinder, and in many instances hydraulic components including hydraulic tubing, and fittings will be adjacent to the cylinder  28 , and immediately behind the attachment plate  24 . Rocks can also fall into openings between the pivoting parts and interfere with movement of the parts. Hydraulic tubing  30  is illustrated in  FIGS. 1 and 4 , for illustrative purposes only. 
         [0014]    The loader  10  has an operator&#39;s cab  32  installed thereon, and the cab has a forward entry door  34  that is shown in cross section, with a glass pane  36  on the forward side. The cab surrounds the operator&#39;s seat or platform, which is entered from the front 
         [0015]    The tilting plate  24  carries a loader bucket  38 , held onto the tilting plate  24  in a normal manner, such as that used on skid steer loaders sold under the trademark BOBCAT. The bucket  38  has a forward edge blade  40 , for digging and loading the bucket with dirt and the like, and a typical load is indicated by line  42 . The bucket  38  is an earth working implement, as is a bulldozer blade. 
         [0016]    The bucket  38  is equipped with a debris guard  44  made according to the present disclosure. The debris guard  44  extends upwardly from the back wall  46  of the bucket, and as can be seen the load  42  can be built up higher than the back wall. The load can include large rocks  48 . 
         [0017]    When the bucket  38  is tilted rearwardly by the cylinder  28 , with the loader arms lowered as shown in dotted lines in  FIG. 1 , the back wall  46  of the bucket will be substantially perpendicular to the ground, and this will tilt the bottom wall of the bucket upwardly as indicated in dotted lines in  FIG. 1 . When the bucket  38  without a debris guard is tilted rearwardly, rocks such as that shown at  48  can spill over the back wall, and then hit the tubing illustrated at  30  or other hydraulic or control components immediately behind the tilting plate  34 . When the lift arm assembly  16  is raised, the bucket  38  will tend to tilt rearwardly more so that any rocks or debris could fall and even strike an operator in the operator&#39;s seat, if there is no cab, and debris can damage the operator&#39;s front window  36 , as well as falling onto the tilt cylinder  28  and conduits leading to controls for that cylinder. 
         [0018]    When the debris guard  44  is installed, the back wall  46  retaining the load  42  is extended to a height that will retain the load, including rocks  48 , in the bucket without spilling over the back wall. 
         [0019]    The debris guard  44  is shown in  FIGS. 3-7  in more detail. The bucket  38 , has an attachment plate  50  that latches onto the tilting plate  24  of the loader to mount the bucket on the loader arms, which are broken away in  FIG. 4 . 
         [0020]    The bucket  38  includes a bottom wall  52 , side walls  54 , and the back or rear wall  46 . The back wall  46  has a formed top rail  58  ( FIG. 6 ), that is secured to a formed top wall section  60  of the rear wall  46 . The top rail  58  also supports operator access steps  62 , that are for the operator to use for entering the operator&#39;s platform, which is entered from the front, through front door  34  of the cab  32  of the loader, when a cab is provided. These steps  62  are provided on standard loader buckets for compact tool carriers such as compact loaders. 
         [0021]    The debris guard  44  is constructed so that it can be easily installed and removed from the bucket back wall  46 . This can be done in the field, so if the conditions are such that a debris guard is desired, it can be quickly and easily attached. The debris guard includes a formed tubular outer frame  66 , that is made of heavy pipe formed into a gentle U-shape where a straight top section  68 , and side legs  70  that have attachment brackets  72  at lower ends thereof. The brackets  72  are bent so a lower portion fits against the back wall with the debris guard inclined forwardly, and are provided with openings through which fasteners, such as bolts  73  can be placed. The bracket  72  can be securely bolted to the back wall  46  of the bucket. 
         [0022]    The frame  66  has a cross plate  74  extending between the legs  70  and the plate has a flange  75  at the front edge. The plate  74  is welded in place to the legs  70 , and braced with gussets  77 . The cross plate  74  is positioned so that it lies along a plane generally from the upper edge of the formed rail  58  to the forward edge of the cutting blade  40 , as shown in  FIG. 5 , and forms a space or opening between the arms  70 , and below the cross member  68  but above the cross plate  74 . This opening is covered with a sturdy open mesh screen  78 , that is welded to the debris guard frame  66 , and the flange  75  of the cross plate  74 . The mesh screen  78  is made of relatively heavy metal wire or rod material, with fairly large openings. For example, a screen made with openings that are in the range of 1 inch to 1.5 inches inside dimension, is suitable, with rods 3/16 to 5/16 inches in diameter, with the preferred opening size being 1.25 inches square with ¼ inch diameter rods. Smaller wire or rods can be used with smaller openings, but visibility should not be overly restricted, and openings that are extra large let debris and rocks fall through. 
         [0023]    The rods or wire for the screen  78  are sturdy, but has large openings that do not substantially affect the visibility through the screen so that an operator of a compact loader can see the bucket blade  40  during operation are desired. 
         [0024]    The cross plate  74  extends rearwardly from the plane of frame  66 , as shown in  FIGS. 5-7 , for example. This plate  74  has cut out sections to form three hooks  82 A,  82 B and  82 C. These hooks include a center hook  82 A between the operator&#39;s steps  62 . Hooks  82 A and  82 B fit on the outside of the operator steps. The cross plate also spaces the screen away from the back wall so the plane of the screen  78  inclines forwardly in the range of 15 to 20 degrees but other inclinations are usable. When material is piled against the forwardly inclined screen, the bucket capacity is about the same as without the debris guard, so the bucket will not be over loaded. 
         [0025]    The hooks  82 A,  82 B. and  82 C have flanges  84 A,  84 B and  84 C that hook over the top rail  58  of the back wall  46 . Hooks  84 A,  84 B and  84 C prevent forward tilting of the debris guard relative to the back wall  46 , and the edges  86  of the cutout sections that form the hooks  82 A,  82 B, and  82 C form stops against the steps  62  to prevent rearward movement of the frame  66  of the debris guard  44 . Once the brackets  72  are both secured in place with bolts  73 , after the hooks have been placed over the top rail  58 , the debris guard is securely held in position and as stated it is angled forwardly. The debris guard is quickly and easily installed. When it is installed, the operator steps  62  are exposed and can be used to enter the operators seat area or, as shown, cab  32  in a normal manner. The steps are easily accessed from the side, and the forward tilting of the debris guard helps the accessibility of the steps. 
         [0026]    Again, the open mesh screen  78 , which is sturdy enough to withstand blows from rocks rolling backwardly on the load  44 , does not obstruct the observation of the bucket by the operator to any substantial degree. 
         [0027]    If the compact loader and bucket are used for loading materials that contain no large rocks or chunks, the debris guard  44  can be removed merely by removing the bolts shown at  73  that hold the brackets  72  in place and then the hooks  82 A,  82 B and  82 C can be lifted off the top rail  58 . 
         [0028]    The debris guard  44  is thus an easily installed accessory that reduces the chances of rocks or other debris from tumbling over the back wall of a loader bucket or over the wall of a bulldozer blade. In the case of use on a loader without a debris guard, when filling the bucket above the operator&#39;s eye level and moving into a bank, the material in the bucket can overflow the bucket back wall and spill back onto the operator. Also spilling back of debris when the bucket is raised for dumping can occur without the present debris guard. With the debris guard installed the spillage over the back is limited and if any material does spill it must pass through the openings in the debris guard screen, so the pieces are small. 
         [0029]    The debris guard is easily manufactured, and easily installed and removed in the field, as desired. The installation features using the hooks and a few fasteners makes field installation when needed and removed when not needed fast and convenient. 
         [0030]    The width of the debris guard, as shown, is generally within the center portions of the width of the back wall of the loader bucket, so that the bucket edges, where loads generally do not pile up as high as in the center are not obstructed. 
         [0031]    The side legs  70  of frame  66  also taper outwardly from the straight top section  68 , to keep the top section of the framework narrower, while providing great stability by having the brackets  72  adequately spaced apart. 
         [0032]    Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.