Abstract:
The invention is a grain tank which pivots about an axis transverse to the direction of travel to facilitate grain flow to the unloading system. The grain tank is sloped and curved to allow the grain to be easily and completely discharged from the tank. Grain is delivered from the clean grain system to a first auger which transports the grain to either a second auger or bubble up auger. The grain can enter the grain tank by the bubble up auger or may be discharged to the unloading system via a second auger. While unloading, the tank pivots from its lowest position to its highest position, only as needed, to maximize output.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims domestic priority on U.S. Provisional Patent Application Ser. No. 60/155,582, filed on Sep. 24, 1999. 
    
    
     BACKGROUND OF INVENTION 
     1. Field of Art 
     This invention relates to the improvement of a grain tank on an agricultural combine. More specifically, the invention allows for the pivoting grain tank to discharge grain from a combine. 
     2. Description of Prior Art 
     Mechanical harvesting of grain has taken place for decades. However, efforts continue in the attempt to make harvesting operations more efficient and effective. A combine harvester generally includes a header, which cuts the crop. The header then moves the cut crop into a feeder house. The feeder house lifts the cut crop into the threshing, separation and cleaning areas of the combine. The grain is separated from the stalk by a rotor or threshing system. The grain is then separated and moved and stored in a grain tank. The chaff and trash are deposited from the rear of the combine. The grain stored in the grain tank is eventually discharged through a grain tank unload tube. An operator usually runs these various operations from a glass-enclosed cab. Typically, the cab is located above and behind the header and feederhouse. There are a variety of agricultural combine harvesters and their operations are well known in the art. For examples of such harvesters reference U.S. Pat. No. 4,846,198 which illustrates the conventional and twin rotor threshing and separating systems of a harvester as well as other major systems of the harvester. See also the New Holland Super Conventional Combines TX™ 66, TX™ 68, the New Holland TWIN ROTOR® combines TR® 89 and TR® 99 for examples of existing conventional and twin rotor harvesters. U.S. Pat. No. 4,332,262 also illustrates the primary systems of a conventional harvester. For further details regarding various agricultural harvester systems review U.S. Pat. Nos. 4,522,553, 4,800,711, 4,866,920, 4,907,402, 4,967,544 and 5,155,984. See also the New Holland corn head model 996 and the New Holland grain belt header model 994 for details regarding headers. 
     The previously mentioned grain is processed in the threshing and separating system. The clean grain then enters a clean grain elevator typically positioned on one side of the combine. The elevator is an endless chain with a series of lift arms attached to the chain. The arms lift the grain upwards. Near the top of the elevator, the grain is deposited into at the base of a bubble-up auger. The bubble-up auger moves the grain upwards and towards the center of the grain tank. At the end of the bubble-up auger the grain is discharged into the grain tank. Some bubble-up augers are hinged near the base so that the auger can rotate or float as the grain fills the grain tank. To discharge the grain from the grain tank, there is an auger positioned at the bottom of the grain tank. This grain tank auger moves grain to a grain tank unloading auger. The grain tank unloading auger is extended away from the grain tank and discharges the grain into a nearby transport vehicle. The base of the grain tank unloading auger may be positioned on the outside of the grain tank. Typically, the unloading auger is positioned at the top of the grain tank or at the base of grain tank. Each design offers unique advantages and disadvantages. When the unloading auger is positioned at the top of the grain tank it is more horizontal. This makes it is less vulnerable to damage by grain transport vehicles and allows better grain discharge control. Plus, the operator can more easily see and position the auger into the transport vehicle. However, the grain needs to be lifted from the base of the grain tank to the top of the grain tank. Each handling operation has the potential of damaging the grain and the added vertical auger causes the unload rate to slowly reduce as the grain tank nears empty. An unloading auger positioned at the base of the grain tank avoids excess handling of the grain, but is more susceptible to damage, reduces control of the discharged grain and limits the operator&#39;s ability to align the unload auger tube with the transport vehicle. It would be desirable to have a grain tank unloading system which would allow for the operator to have maximum grain visibility and control without excess handling of grain. Another dilemma occurs when an operator would prefer to discharge grain from the grain tank while still undertaking So harvesting operations. As previously mentioned, the grain presently exits the clean grain elevator, passes through the bubble-up auger and then is moved to the grain tank unloading auger by the grain tank auger. This repetitive handling results in damage to the grain. A final dilemma exists as a result of transporting combine between different crops, countries or regions. Typically, when a combine harvester is transported across a national border or certain state borders, it needs to be completely cleaned and all grain removed. With all of the contours of the grain tank and the various augers, this becomes a time consuming process. A grain tank that would allow complete removal of the harvested grain and facilitate cleaning the rest of the machine would be a great improvement. 
     An invention that could resolve these issues would represent an improvement to the art. 
     OBJECTS OF THE INVENTION 
     It is an object of the present invention to provide a pivoting grain tank. 
     It is an object of the present invention to provide a pivoting grain tank that rotates about a pivot axis transverse to the forward direction of travel for a combine harvester. 
     It is an object of the present invention to provide a pivoting grain tank with sloped walls that allows all grain to be easily removed from the grain tank. 
     It is an object of the present invention to provide a grain tank which allows the grain to be discharged from the tank with a minimum of grain handling and at a nearly constant rate. 
     It is an object of the present invention to provide a grain tank that moves the unload tube forward to improve the operator&#39;s view of the unload process and to reduce the unload tube&#39;s rear overhang when its in the transport position. 
     It is an object of the present invention to provide a series of augers nearly co-axial to the grain tank&#39;s pivot axis. 
     It is an object of the present invention to provide a top hatch on the pivoting grain tank by for easy access to the grain tank. 
     It is an object of the present invention to provide a grain tank where incoming clean grain may be transported directly to the grain tank unload tube without passing through the bubble up auger. 
     SUMMARY OF THE INVENTION 
     The invention is an improvement to the grain tank on an agricultural combine. The invention consists of a grain tank that pivots about an axis transverse to the direction of travel to assist in the removal of grain from the grain tank. Incoming clean grain enters a first auger which moves the grain to either a bubble up auger or second auger. At this point, the grain either enters the bubble up auger to be stored in the grain tank or passes to the second auger and an unloading tube. The first and second augers maybe surrounded by an auger tube with several ports. One or more of these ports can align with the tank, allowing the grain to enter the grain tank, when the grain tank is in the lowered or storage position. Conversely, there are additional ports which allow grain from the grain tank to enter the first and second augers when the grain tank unloading. Since the grain tank has sloped and concave surfaces, almost all tank grain can be discharged. Any grain that remains, can be easily swept through clean out ports in the tank&#39;s flat bottom. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is a side view of the combine having the present invention. 
     FIG. 2 is a side view of the combine having the present invention wherein the pivoting grain tank has been rotated upwards and the unload auger has been extended. 
     FIG. 3 is an overhead view of the grain tank. 
     FIG. 4 is cutaway view of the tank along line  4 — 4  in FIG. 3 while the grain tank is in the lowered position. 
     FIG. 5 is a close-up view of FIG. 4 showing the auger tube. 
     FIG. 6 is a cutaway view of the tank along line  6 — 6  in FIG. 3 after the grain tank has been partially rotated into the upward or unloading position. 
     FIG. 7 is a close up view of FIG. 6 showing the auger tube. 
     FIG. 8 is a cutaway view of the tank along line  8 — 8  in FIG. 3 while the grain tank is in a lowered position. 
     FIG. 9 is a close up view of FIG. 8 showing the auger tube. 
     FIG. 10 is a cutaway view of the tank along line  10 — 10  in FIG. 3 while the grain tank is in a partially raised position. 
     FIG. 11 is a close up view of the FIG. 10 showing the auger tube. 
     FIG. 12 is a close up view of the inner region having the light and sensor. 
     FIG. 13 is a close up view of the grain tank in the unload position with the lift cylinder extended. 
     FIG. 14 is a view of the interior of the grain tank showing the inner region, side wall and window. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, it is possible to observe the major elements and general operation of the present invention. Left and right references are used as a matter of convenience and are determined by standing at the rear of the combine and facing the forward end in the normal direction of travel. Likewise, forward and rearward are determined by normal direction of travel of the combine. Upward or downward orientations are relative to the ground or operating surface. Horizontal or vertical planes are also relative to ground. 
     As seen in FIG. 1, the invention is located on a typical twin rotor combine  1  having a pair of front wheels  8  (only one shown) and a pair of rear wheels  9  (only one shown) for providing movement over the ground. At the front of the combine is a header (not shown) for cutting a crop. As the combine  1  and header  12  are moved forward, the header cuts the grain and stalk. The header moves the grain into an auger trough. A transverse auger pushes the grain and stalk in the auger trough to the center of the header. The header  12  may be positioned and re-positioned relative to the ground. The header may also be tilted to the left or right or may be positioned relatively high or low to the ground. These features are constantly being adjusted depending on the terrain and crop conditions. Moveable headers are well known and established in the art. Located at the rear center of the header is the feederhouse  4  or elevator. The feederhouse  4  moves the grain and stalks rearward into the threshing  3 , separation, cleaning and clean grain systems of the combine  1 . As seen in FIG. 1, the threshing  3 , separation and cleaning system is a TWIN ROTOR® (system used on TR 98 combines. However, the invention is also applicable to the AXIAL FLOW ® (single rotor) combine. The design and operation of these systems are well known and described in the prior art. After processing, separation and cleaning the grain is stored in a grain tank system  20  located near the top of the combine  1 . The grain is transferred from the grain tank system  20  to a transport vehicle by an unloading auger through the grain tank unload tube  6 . Usually during the harvesting operations, the unloading auger remains undriven and the grain tank unload tube  6  remains retracted as shown in FIG.  1 . However, the combine can be unloaded ‘on the go’. A separate vehicle such as a truck or tractor-pulled grain cart drives beside the moving combine. The processed grain is discharged while the combine and receiving vehicle are moving. As shown in FIG. 2, after sufficient grain has been accumulated in the grain tank  30 , the operator extends the unload tube  6 . The operator then positions the end of the unload tube  6  over the receptacle. Unloading augers and unload auger grain tubes are well known and established in the art. The trash or chaff is ejected from the rear of the combine by a chaff spreader  10 . The operator controls the combine  1  from the cab  2  located behind the header and at the front of the combine. From the cab the operator can observe most the various combine functions. The cab  2  usually has a large glass window or several windows which afford the operator the maximum ability to monitor the header. The combine  1  and various systems are powered by an engine  7  generally positioned at the rear of the combine  1 . Most of the major systems in a combine are discussed and well known in the prior art. 
     The present invention focuses on the grain tank dump system  20  which can be generally observed in FIG. 1 and 2. FIG. 1 shows the grain tank  30  in the down or storage position and FIG. 2 shows the grain tank in the upward or unloading position. FIGS. 3 and 4 provide a general schematic view of the tank. Generally, the crop enters the grain tank  30  through the clean grain elevator  25 . The crop flow  60  exits the grain elevator  25  and is moved by the first auger  40 . The grain either enters a bubble-up auger  55  or continues over to the second auger  45 . The grain flow  63  in the second auger is discharged into the unload turret. The grain which enters the bubble up auger  55  is discharged into the grain tank  30 . When the grain tank  30  is full the unloading auger is extended over the transport vehicle, the unloading system drives are engaged (this disengages the drive to the bubble up auger  55 ). Then, tank  30  is rotated upwards about the first and second augers  40  and  45 , as needed to keep the unloading system full of grain. Grain from grain tank  30  is moved to the turret  6  via the first and second augers  40  and  45 . As seen in FIG. 2, while this unloading operation is occurring, the unload tube  6  is extended and is discharging the grain into a grain wagon or similar conveyance (not shown). 
     Now that the general elements have been reviewed it is possible to discuss the invention in greater detail. The pivoting grain tank  30  consists of a curved grain tank as viewed in FIGS. 2 and 3. The tank  30  has a pair of opposing side walls  31 E. Attached to the side walls  31 E is the concave region  31 D (as seen in FIG. 4,  6 , 8  and  10 ). Attached to the concave region  31 D is the inner region  31 C. Attached to the inner region  31 C and opposing the concave region  31 D is the concave auger region  41 . Attached to the concave auger region  41  is the top region  31 B. Affixed to the top region  31 B is the top hatch. The top hatch is hinged to the top region  31 B. The top hatch can be opened to allow access to the interior of the grain tank  30 . Also attached to the circumference of the concave auger region  41  is a cover  42  (FIGS.  8  and  9 ). As seen in FIGS. 6 and 10, the inner region  31 C and top region  31 B slope towards the concave auger region  41  when the tank is rotated upwards to an unloading position. Attached between the side walls  31 E and the combine frame  35  are a pair of conventional hydraulic lift cylinders  34  (FIG.  13 ). The side walls  31 E have a recessed portion that an end of the hydraulic lift cylinder  34  is attached to. Windows ( 32 ) allow an operator in the cab to view the interior of the lowered grain tank  30  (FIGS.  13  and  14 ). As seen in FIGS. 3 and 5, there is a sump  43  attached to the concave auger region  41 . Attached to the sump is a bubble up auger  55 , which discharges at an exit or discharge  55 A. The bubble up auger is powered by a conventional hydraulic motor  56  (FIG.  13 ). There is also a light  38  (FIG. 12) which can be attached to the side wall  31 E. A sensor  39  (FIG. 12) can also be affixed to the side wall  31 E to allow for the detection of grain. The sensor can inform the operator when the grain tank  30  is full and that grain covers the second auger  45 . The sensor can also directly control the tank&#39;s pivotal movement. 
     Inside and generally co-axial to the concave auger region  41  is the first auger  40  and second auger  45 . The first auger  40  is powered by a typical chain and sprocket drive with grain elevator  25 . The second auger has a separate mechanical drive. The unloading auger system is rotated by a hydraulic drive (not shown) which alternatively powers motor  56  and the bubble up auger  55 . Surrounding the first and second augers  40  and  45  is a fixed auger tube  50 . The auger tube  50  has a sump port  52  and several auger ports  51 . The fixed auger tube  50  and augers  40  and  45  are co-axially aligned. The auger ports  51  in the auger tube  50  are positioned proximate to the first auger  40  and second auger  45 . The sump port  52  is positioned below first auger  40  and above the sump  43 . The sump  43  passes grain to and from the bubble up auger  55 . The orientation of the cover  42 , auger ports  51  and sump port  52  on the auger,tube  50  will be discussed later. 
     As previously, briefly discussed and seen in FIG. 3, the crop flow  60  is lifted by the clean grain elevator  25  from the cleaning and separating shoes (not shown). The elevator  25  is a conventional clean grain elevator having a series of lift arms mounted on an endless chain. The chain is driven by an elevator drive which is conventionally a belt driven sheave  27 . At the top of the elevator  25 , the crop flow  60  exits the elevator and is deposited onto the first auger  40 . The first auger  40  is a conventional auger within a fixed auger tube  50 . The crop flows (arrow  61 ) along the first auger  40  until it reaches the sump port  52  and sump  43  for the bubble up auger  55  or second auger  45 . 
     Only with the tank lowered hydraulic motor  56  operates the bubble up auger  55 . Alternately a second hydraulic motor drives the unloading auger system  6 . If the bubble up auger  55  is operating, then the unloading auger system and second auger  45  are shut off. As seen in FIG. 4 and 5, the grain exits the sump port  52  into the sump  43  and bubble up auger  55 . The grain is then moved by the bubble up auger  55  (as seen by arrow  62 ), thus filling the grain tank  30 . As tank  30  becomes nearly full, the grain level rises above the auger tube  50  and auger ports  51 . Some grain is free to flow through the exposed auger ports  51  into the auger tube  50  and static second auger  45 . With the grain tank  30  in the filly down position, and the unloading drives engaged, grain can flow from the top of tank  30  to the second auger  45  and unloading auger system. At the same time, the bubble up auger  55  will stop, sump  52  will fill and the crop  61  will pass to the second auger  45 . As needed to maintain exit flow, the grain tank  30  can be rotated upwards when the lift cylinders  34  are extended. The grain tank  30  pivots about a pivot axis  33  which is transverse to the combine&#39;s normal, forward direction of travel  11 . The pivot axis  33  is co-axial with the first and second augers  40  and  45  and generally co-axial to the concave auger region  41 . As the lift cylinders rotate the grain tank  30 , grain continues to re-enter the auger tube  50  through the auger ports  51  positioned about the second auger  45 . The second auger  45  pushes the grain to the unloading auger system to be unloaded (as seen in arrow  63 ). Regardless of its contents, with the grain tank  30  in the fully down position and the unloading drives engaged it&#39;s possible to move grain directly from the clean grain system to the unloading auger system. In this scenario, the bubble up auger  55  drive is turned off and auger  45  and the unloading auger system drives are engaged. The grain passes directly from the first auger  40  to the second auger  45  and is then forwarded to the unloading auger system (as seen in arrow  63 ). 
     Auger ports  51  on the auger tube  50  allow for the grain to re-enter the second auger  45  anytime. Auger ports  51  allowing grain to re-enter the first auger  40  are restricted. Specifically, the auger ports  51  are covered by the cover  42  when the grain tank  30  is lowered (as seen in FIGS.  8  and  9 ). When the tank  30  is raised, the cover  42  rotates with the tank to allow grain from the tank  30  to pass through auger ports  51  to the first auger  40 . Only one auger port  51  in the auger tube  50 , or multiple ports in the tube  50  are possible. The sump port  52  in the auger tube  50  aligns with the sump  43  when the tank  30  is in the lowered position (as seen in FIGS. 3,  4  and  5 ). When the tank  30  is raised, sump  43  aligns with an auger port  51 . This allows grain to back feed from sump  43  and the bubble up auger  55  to the first auger  40 . 
     The advantages to the present invention allow for the grain to either be conveyed directly from the clean grain system to the unloading auger system without excess handling exhibited by present combines. Additionally, the slope of the inner tank surfaces allow the grain to easily empty from the grain tank  30 . This is especially advantageous when the combine is transported across national borders. All of the grain is removed easily from the tank  30 . Additionally by being able to rotate the tank to the raised or unload position  70 , it is possible to gain cleaning access to the engine, threshing and cleaning systems and for easier maintenance. Usually the bulk of the volume of grain positioned in the grain tank  30  is positioned beneath the pivot axis  33  and concave auger region  41 . This keeps the center of gravity of the grain tank  30  low and improves stability of the entire combine. It should be recognized that the sensor  39  can control the extension of the lift cylinders  34  and the lifting of grain tank  30 . 
     It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what illustrated in the drawings and described in the specification.