Abstract:
An agricultural harvester includes a chassis, an axle assembly carrying the chassis, a plurality of hub assemblies including a first hub assembly and a second hub assembly, the hub assemblies coupled to a corresponding end of the axle assembly, and a plurality of ground engaging devices each being coupled to a corresponding hub assemblies. The ground engaging devices support the axle assembly and the chassis. The axle assembly includes an extendable/retractable axle for altering a distance between the ground engaging devices that are coupled to the hub assemblies, and a connecting rod extending/retracting from a central portion of the axle assembly, the connecting rod also coupled to a portion of the first hub assembly. The connecting rod is generally vertically displaced from the extendable/retractable axle.

Description:
[0001]    This application claims priority to Belgium Application BE2014/0850 filed Dec. 18, 2014, which is incorporated herein by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to agricultural harvesters, and, more specifically to axle systems for use with agricultural harvesters. 
         [0003]    An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions with a single harvesting unit, such as picking, threshing, separating and cleaning. A combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves and performs a threshing operation on the crop to remove the grain. Once the grain is threshed it falls through perforations in the concaves onto a grain pan. From the grain pan the grain is cleaned using a cleaning system, and is then transported to a grain tank onboard the combine. A cleaning fan blows air through the sieves to discharge chaff and other debris toward the rear of the combine. Non-grain crop material such as straw from the threshing section proceeds through a residue system, which may utilize a straw chopper to process the non-grain material and direct it out the rear of the combine. When the grain tank becomes full, the combine is positioned adjacent a vehicle into which the grain is to be unloaded, such as a semi-trailer, gravity box, straight truck, or the like; and an unloading system on the combine is actuated to transfer the grain into the vehicle. 
         [0004]    More particularly, a rotary threshing or separating system includes one or more rotors which can extend axially (front to rear) or transversely within the body of the combine, and which are partially or fully surrounded by a perforated concave. The crop material is threshed and separated by the rotation of the rotor within the concave. Coarser non-grain crop material such as stalks and leaves are transported to the rear of the combine and discharged back to the field. The separated grain, together with some finer non-grain crop material such as chaff, dust, straw, and other crop residue are discharged through the concaves and fall onto a grain pan where they are transported to a cleaning system. Alternatively, the grain and finer non-grain crop material may also fall directly onto the cleaning system itself. 
         [0005]    A cleaning system further separates the grain from non-grain crop material, and typically includes a fan directing an airflow stream upwardly and rearwardly through vertically arranged sieves which oscillate in a fore and aft manner. The airflow stream lifts and carries the lighter non-grain crop material towards the rear end of the combine for discharge to the field. Clean grain, being heavier, and larger pieces of non-grain crop material, which are not carried away by the airflow stream, fall onto a surface of an upper sieve (also known as a chaffer sieve) where some or all of the clean grain passes through to a lower sieve (also known as a cleaning sieve). Grain and non-grain crop material remaining on the upper and lower sieves are physically separated by the reciprocating action of the sieves as the material moves rearwardly. Any grain and/or non-grain crop material remaining on the top surface of the upper sieve are discharged at the rear of the combine. Grain falling through the lower sieve lands on a bottom pan of the cleaning system, where it is conveyed forwardly toward a clean grain auger. 
         [0006]    The clean grain auger conveys the grain to a grain tank for temporary storage. The grain accumulates to the point where the grain tank is full and is discharged to an adjacent vehicle such as a semi trailer, gravity box, straight truck or the like by an unloading system on the combine that is actuated to transfer grain into the vehicle. 
         [0007]    As harvesters increase in size and have longer headers, when on uneven ground the axle system of the harvester can cause the harvester to tilt with the ground and result in less than ideal stability of the harvester on the ground. 
         [0008]    What is needed in the art is a cost effective and efficient way to extend axles on an agricultural harvester. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides for a tilting extendable/retractable axle assemblies for an agricultural harvester. 
         [0010]    The invention in one form is directed to an agricultural harvester including a chassis, an axle assembly carrying the chassis, a plurality of hub assemblies including a first hub assembly and a second hub assembly, the hub assemblies each being coupled to a corresponding end of the axle assembly, and a plurality of ground engaging devices each being coupled to a corresponding one of the hub assemblies. The ground engaging devices support the axle assembly and the chassis. The axle assembly includes an extendable/retractable axle for altering a distance between the ground engaging devices that are coupled to the hub assemblies, and a connecting rod extending/retracting from a central portion of the axle assembly, the connecting rod being also coupled to a portion of the first hub assembly. The connecting rod being generally vertically displaced from the extendable/retractable axle. 
         [0011]    An advantage of the present invention is that it provides for an extended ground profile to enhance stability of the harvester on uneven ground. 
         [0012]    Another advantage is that the ground profile of the harvester can be diminished for road transport. 
         [0013]    Yet another advantage is that it allows for larger operation angles for the harvester. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0015]      FIG. 1  is a side view of an embodiment of an agricultural harvester in the form of a combine; 
           [0016]      FIG. 2  is a front view of an embodiment of an axle assembly for use on the agricultural harvester of the present invention; 
           [0017]      FIG. 3  is another view of the axle assembly of  FIG. 2  with the hub assemblies extended; 
           [0018]      FIG. 4  is another view of the axle assembly of  FIGS. 2 and 3  with the hub assemblies retracted and the axle assembly tilted; and 
           [0019]      FIG. 5  is yet another view of the axle assembly of  FIGS. 2-4  with the axles extended and tilted. 
       
    
    
       [0020]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    The terms “grain”, “straw” and “tailings” are used principally throughout this specification for convenience but it is to be understood that these terms are not intended to be limiting. Thus “grain” refers to that part of the crop material which is threshed and separated from the discardable part of the crop material, which is referred to as non-grain crop material, MOG or straw. Incompletely threshed crop material is referred to as “tailings”. Also the terms “forward”, “rearward”, “left” and “right”, when used in connection with the agricultural harvester and/or components thereof are usually determined with reference to the direction of forward operative travel of the harvester, but again, they should not be construed as limiting. The terms “longitudinal” and “transverse” are determined with reference to the fore-and-aft direction of the agricultural harvester and are equally not to be construed as limiting. 
         [0022]    Referring now to the drawings, and more particularly to  FIG. 1 , there is shown an agricultural harvester in the form of a combine  10 , which generally includes a chassis  12 , ground engaging wheels  14  and  16 , a header  18 , a feeder housing  20 , an operator cab  22 , a threshing and separating system  24 , a cleaning system  26 , a grain tank  28 , and an unloading conveyance  30 . Unloading conveyor  30  is illustrated as an unloading auger, but can also be configured as a belt conveyor, chain elevator, etc. 
         [0023]    The front wheels  14  are larger flotation type wheels, and the rear wheels  16  are smaller steerable wheels. Motive force is selectively applied to the front wheels  14  through a power plant in the form of a diesel engine  32  and a transmission (not shown). Although the combine  10  is shown as including wheels, is also to be understood that the combine  10  may include tracks, such as full tracks or half tracks. 
         [0024]    The header  18  is mounted to the front of the combine  10  and includes a cutter bar  34  for severing crops from a field during forward motion of the combine  10 . A rotatable reel  36  feeds the crop into the header  18 , and a double auger  38  feeds the severed crop laterally inwardly from each side toward the feeder housing  20 . The feeder housing  20  conveys the cut crop to the threshing and separating system  24 , and is selectively vertically movable using appropriate actuators, such as hydraulic cylinders (not shown). 
         [0025]    The threshing and separating system  24  is of the axial-flow type, and generally includes a rotor  40  at least partially enclosed by and rotatable within a corresponding perforated concave  42 . The cut crops are threshed and separated by the rotation of the rotor  40  within the concave  42 , and larger elements, such as stalks, leaves and the like are discharged from the rear of the combine  10 . Smaller elements of crop material including grain and non-grain crop material, including particles lighter than grain, such as chaff, dust and straw, are discharged through perforations of the concave  42 . Although the threshing and separating system  24  is illustrated as being of an axial-flow type having a rotor, it is also contemplated to use the present invention with other conventional threshing systems. 
         [0026]    Grain which has been separated by the threshing and separating assembly  24  falls onto a grain pan  44  and is conveyed toward the cleaning system  26 . The cleaning system  26  may include an optional pre-cleaning sieve  46 , an upper sieve  48  (also known as a chaffer sieve), a lower sieve  50  (also known as a cleaning sieve), and a cleaning fan  52 . Grain on the sieves  46 ,  48  and  50  is subjected to a cleaning action by the fan  52  which provides an airflow through the sieves to remove chaff and other impurities such as dust from the grain by making this material airborne for discharge from the straw hood  54  of the combine  10 . The grain pan  44  and the pre-cleaning sieve  46  oscillate in a fore-to-aft manner to transport the grain and finer non-grain crop material to the upper surface of the upper sieve  48 . The upper sieve  48  and the lower sieve  50  are vertically arranged relative to each other, and likewise oscillate in a fore-to-aft manner to spread the grain across the sieves  48 ,  50 , while permitting the passage of cleaned grain by gravity through the openings of the sieves  48 ,  50 . 
         [0027]    Clean grain falls to a clean grain auger  56  positioned crosswise below and in front of the lower sieve  50 . The clean grain auger  56  receives clean grain from each sieve  48 ,  50  and from the bottom pan  58  of the cleaning system  26 . The clean grain auger  56  conveys the clean grain laterally to a generally vertically arranged grain elevator  60  for transport to the grain tank  28 . Tailings from the cleaning system  26  fall to a tailings auger trough  62 . The tailings are transported via the tailings auger  64  and the return auger  66  to the upstream end of the cleaning system  26  for repeated cleaning action. The cross augers  68  at the bottom of the grain tank  28  convey the clean grain within the grain tank  28  to the unloading auger  30  for discharge from the combine  10 . 
         [0028]    The non-grain crop material proceeds through a residue handling system  70 . The residue handling system  70  may include a chopper, counter knives, a windrow door and a residue spreader. 
         [0029]    Axle assemblies  72  and  74  carry the chassis  12  and are respectively coupled to the wheels  14  and  16 . The axle assemblies  72  and  74  are pivotal with regard to the chassis  12  and, allow for the wheels  14  and  16  to remain in a generally vertical orientation regardless of the tilt of the axle assemblies  72  and  74 . 
         [0030]    Now, additionally referring to  FIGS. 2 and 3  there is shown and illustrated additional details of the axle assemblies  72  and  74 , hereafter whatever is discussed about one axle assembly  72  or  74  is generally applicable to the other. The axle assembly  72  includes hub assemblies  76  and  78 , extendable/retractable axles  80  and  82 , extendable/retractable upper connecting rods  84  and  86 , a central area  88 , and solenoids  90 ,  92 ,  94  and  96 . The axle assembly  72  is pivotal about pivot  98  allowing the axle assembly  72  to pivot on uneven ground while keeping the chassis  12  generally level from side-to-side. The upper connecting rods  84  and  86  are pivotally coupled to the chassis  12  at pivot  100 , which is generally above pivot  98 . It is also contemplated that the connecting rods  84  and  86  can be below the axles  80  and  82 , and the connecting rods  84  and  86  can be described as being generally vertically displaced from axles  80  and  82 . 
         [0031]    For the sake of clarity in the discussion and illustration of the invention the wheels  14  as well as drive components, and details of the hub assemblies  76  and  78  are not included in  FIGS. 2-5 . 
         [0032]    Actuators  102  are situated to cause the synchronized extension or retraction of axles  80  and  82  along with connecting rods  84  and  86 . When the agricultural harvester  10  is in a travel mode it is desirable to have wheels  14 , more generally ground engaging devices  14 , close together as illustrated in  FIG. 2 . Conversely, when in a field operational mode it may be advantageous to have the hub assemblies  76  and  78 , and thus the wheels  14 , in an extended position to enhance the stability of the agricultural harvester  10 , as shown in  FIG. 3 . 
         [0033]    In transitioning to/from the travel mode or the field operational mode, a sequence of operations take place. First, the solenoids  90 ,  92 ,  94  and  96  are activated so that they unlock or disengage from holding the axles  80 ,  82  and the connecting rods  84 ,  86  in the particular mode that they are changing from. Next, as the agricultural harvester  10  is moving on the ground, the actuators  102  are activated to cause the movement (either extending or retracting) of the axles  80 ,  82  and the connecting rods  84 ,  86 . The actuators  102  are sized to be able to effect the transition only as the agricultural harvester  10  is moving. Once axles  80 ,  82  and connecting rods  84 ,  86  are in their new position, then solenoids  90 ,  92 ,  94  and  96  are altered so that they now lock or engage the axles  80 ,  82  and connecting rods  84 ,  86  so that they are locked into position. 
         [0034]    Now, additionally referring to  FIGS. 4 and 5  there is shown the axle assembly  72  in an angled orientation in both the retracted and the extended mode. The tilt of the axle assembly  72  corresponds to a ground contour variance that is compensated by keeping the chassis  12  generally level while the axle assembly  72  tilts. The extended mode illustrated in  FIG. 5  provides enhanced stability on sloping ground, while the axle assembly  72  keeps the hub assemblies  76  and  78  in a preferred orientation to keep the wheels  14  in a generally vertical orientation. 
         [0035]    The present invention builds a telescopic traction axle with an extended or wider wheelbase during field operations to have a positive impact on the machine performance When the harvester  10  is in the field the operator releases the solenoids  90 ,  92 ,  94 ,  96  that unlocks the axle extensions. Then the extension hydraulics are engaged and the axle extends along with stabilizers, which are pushed outwards until the solenoids lock the axle in position when fully extended. As discussed above, due to the weight of the harvester  10 , the harvester  10  will typically need to be rolling forward at a slow, steady pace as the actuators  102  extend the axles  80 ,  82  and connecting rods  84 ,  86 . It is contemplated that intermediate positions between fully retracted and fully extended can also be arranged with the solenoids  90 ,  92 ,  94 ,  96  locking at the intermediate positions. 
         [0036]    While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.