Abstract:
A tractor having a cargo box and an axle mounted hitch ball in which the hitch ball projects upward through an opening in the cargo box floor. This arrangement enables the ball to be used when the cargo box is mounted to the tractor. Furthermore, since the ball is mounted to the axle and not the cargo box, greater load carrying capacity is achieved and the hitch can be used when the box removed from the tractor.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application is a division of applicant&#39;s co-pending application U.S. Ser. No.  10 / 162 , 854 , filed Jun. 5, 2002 and titled REMOVABLE HITCH BALL, which application is pending. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a tractor and in particular to a tractor having a cargo box and a removable hitch ball mounted above the rear axle thereof.  
         BACKGROUND OF THE INVENTION  
         [0003]    An agricultural tractor is a traction machine intended primarily for off-road usage and designed primarily to supply power to implements. An agricultural tractor propels itself and provides a force in the direction of travel and may provide mechanical, hydraulic and/or electrical power to implements to enable them to perform their intended functions. A typical agricultural tractor however does not have provision for carrying materials or other cargo. A utility transport tractor is a specialty type of agricultural tractor that combines the primary function of an agricultural tractor described above with the capability to transport materials. Configurations may include cargo boxes or tanks for transport of materials.  
           [0004]    As used herein the term “tractor” refers to a traction machine intended primarily for off-road use and designed to supply power to an implement. However, it is not limited to tractors solely for agricultural use but tractors that are also used in other contexts, such as in grounds care, golf course maintenance, park maintenance, forestry service, etc.  
         SUMMARY OF THE INVENTION  
         [0005]    The tractor of the present invention is similar in configuration to an agricultural tractor, having larger rear drive wheels. However, the operator&#39;s station is moved forward of the rear axle and a cargo box, preferably a dump box, is mounted to the tractor behind the operator&#39;s station and above the rear axle. A standard three-point hitch extends rearward from the rear axle, as does a draw bar for towing implements. To provide further utility, a hitch ball is removably mounted above the rear axle of the tractor to enable a portion of the towed load to be transmitted onto the tractor chassis. By mounting the hitch ball above the rear axle as opposed to mounting the hitch ball at the end of the draw bar, a closer coupling of the tractor and trailer is achieved, providing improved maneuverability.  
           [0006]    Since both the hitch ball and the cargo box are mounted above the axle, the cargo box is provided with an opening in the floor through which the hitch ball extends. Furthermore, the hitch ball is removably mounted to the tractor so that it can be removed when not in use. A cover closes the opening in the cargo box floor when the hitch ball is not in use. The cargo box is removably mounted to the tractor. When removed, the hitch ball remains available for use as it is separately mounted to the tractor and not mounted through the cargo box. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    [0007]FIG. 1 is a perspective view of the tractor of the present invention.  
         [0008]    [0008]FIG. 2 is a side view of the tractor of the present invention.  
         [0009]    [0009]FIG. 3 is a perspective view of the power train portion of the tractor chassis.  
         [0010]    [0010]FIG. 4 is a fragmentary perspective view of the rear axle and hitch ball mounting structure.  
         [0011]    [0011]FIG. 5 is a rear perspective view of the tractor with the cargo box removed.  
         [0012]    [0012]FIG. 6 is a rear perspective view similar to FIG. 5 with the cargo box attached to the tractor.  
         [0013]    [0013]FIG. 7 is a perspective view of the hitch ball mounting bracket.  
         [0014]    [0014]FIG. 8 is a sectional view as seen from substantially the line  8 - 8  through the hitch ball mounting bracket with the ball removed.  
         [0015]    [0015]FIG. 9 is a perspective view of the steel structure of the cargo box.  
         [0016]    [0016]FIG. 10 is a perspective view of the left side molded plastic side panel for the cargo box. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0017]    With reference to FIG. 1, the tractor of the present invention is shown and designated generally at  10 . The tractor  10  has a front hood  12  covering an engine  13 , FIG. 3 The tractor further includes rear drive wheels  14  on a rear axle  15  and front wheels  16  on a front axle  17 , all part of the tractor chassis  19 . The front wheels  16  can be driven or non-driven. An operator&#39;s station  18  is located forward of the rear wheels and includes a center operator&#39;s seat  20  and left and right passenger seats  22 ,  24 . A cargo box  26  is located rearward of the operator&#39;s station  18  and generally above the rear axle  15 . A three point hitch  28 , FIG. 2, is mounted behind the rear axle and beneath the cargo box  26 . The three point hitch includes a pair of draft links  30  and an upper link  32 .  
         [0018]    The cargo box  26  has a generally horizontal floor  34 , an upright front wall  36 , left and right side walls  38  and a tailgate  40 . The cargo box side walls form wheel wells for the rear wheels with a portion of the cargo box being disposed above each rear wheel. Fenders  43  are attached to the tractor chassis and are shaped to partially fit within the cargo box wheel wells. The cargo box also has a pair of side frame rails  108 .  
         [0019]    The powertrain portion of the chassis  19  is shown in greater detail in FIG. 3. There the engine  13  is shown together with a transmission  46  leading to the rear drive axle  15 . The rear drive axle includes left and right axle housings  48  as shown in FIG. 4 and a central differential housing  50  shown in FIG. 3. The chassis further includes frame rails  52  that are used primarily to mount and support the cargo box  26 . The cargo box is pivotally mounted at the mounting bosses  54  at the rear of the frame rails  52 . Lift cylinders  56  extend from the axle housings  48  to the cargo box and are extendable to tilt the cargo box to a raised dump position.  
         [0020]    A hitch ball  60  is mounted to and above the axle  15  through a mounting bracket  62  coupled to each of the left and right axle housings  48 . A pair of laterally extending braces  64  further couples the bracket  62  to one frame rail  52 . The hitch ball  60  is removably mounted to the bracket  62  as described below. When the hitch ball is mounted to the bracket and the cargo box  26  is also mounted, the hitch ball  60  extends through an opening in the cargo box floor as shown in FIGS. 2 and 6. By extending through the cargo box floor, the hitch ball  60  can be mounted directly to the chassis and still be available for use with the cargo box  26  attached to the vehicle. This provides greater load carrying capacity with the ball mounted to the chassis then if the ball is mounted to the cargo box. Furthermore, the hitch ball is available during time periods when the cargo box is removed from the tractor.  
         [0021]    With reference to FIGS. 7 and 8, the removable mounting of the hitch ball  60  is shown in greater detail. The top plate  70  of the bracket  62  has left and right weldments  72  welded thereto. The weldments  72  each consist of two metal strips welded together to the top plate  70 . The weldments form channels  74  that receive opposite edges of a base plate  76  to which the hitch ball  60  is fixed. The weldments  72  taper toward one another in one direction forming a wedge fitting for the base plate  76 . A catch strap  78  is inserted across the two channels  74  to trap the base plate  76  therein. In FIG. 4, the weldments taper toward the rear of the tractor while in FIG. 5 the weldments taper toward the front of the tractor. Either direction can be used.  
         [0022]    With reference to FIG. 9, the steel components of the cargo box are shown. The floor  34  and lower portions  80  of the two side walls are made of steel. The steel components also include the cargo box frame rails  108 , side brackets  82  and an upper frame  84  the top of the side and front walls. A cover  86  is placed in the opening in the cargo box floor that provides access for the hitch ball  60 . An upper portion  88  of the box left side wall is shown in FIG. 10. The upper portion  88  is a plastic molded body that is bolted to the lower portion  88  of the side wall as well as the upper frame  84 . The right side upper panel  88  is similarly constructed. The front wall  36  is also a plastic molded panel that is bolted to the in-turned flanges  90  of the side wall lower portions, to the up-turned front flange  92  on the bottom of the floor  34  and to the upper frame  84 . By constructing the cargo box of both plastic and metal components, the overall weight of the cargo box can be reduced while still providing high strength load carrying structure of the cargo box.  
         [0023]    Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.