BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention is directed toward a combine header unit and methods of harvesting using the same. More specifically, the combine header includes a feederhouse that is divided into a plurality of passages and a shuttle gate positioned in front of the feederhouse for selectively blocking access to a particular passage and directing the harvested grain to an unobstructed passage.  
         [0003]     2. Description of the Prior Art  
         [0004]     It is a common practice to plant numerous test and research grain plots within a single field. Generally, these test plots are planted in parallel rows with a dedicated alley to separate each of the individual grain plots. A variety of grains may be planted within these rows. It is imperative that the grain varieties be separately contained during harvesting to ensure accurate classification of the grain properties, like moisture content, grain temperature, protein content, oil content, density, and weight.  
         [0005]     To ensure this separation, existing techniques require a combine operator to pause forward movement through the field upon reaching an alley to allow the grain from the previous plot to “clean-out” of the system, to be weighed, bagged and identified. This stop and go movement upon reaching an alley places a significant amount of stress on the machine and its operator and also accounts for a significant amount of the overall time spent harvesting the grain.  
         [0006]     Therefore, there is a need in the art for apparatus and methods of harvesting test and research grain plots in a continuous manner thereby reducing the wear on the harvesting machine and reducing the time required to harvest a given number of plots thus and preventing operator fatigue.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention overcomes the above problems by providing apparatus and methods for harvesting multi-crop research plots efficiently without having to halt forward progress of the combine or stop, impede or slow the movement of any internal component of the combine.  
         [0008]     In one embodiment of the present invention there is provided a combine header comprising: a feederhouse assembly that is divided into at least first and second passages; a rotatable auger; and a shiftable gate slidably mounted on the header aft of the auger and forward of the feederhouse, the gate shiftable between a first position wherein the gate covers the first feederhouse passage so as to block access to the first passage and a second position wherein the gate covers the second passage leaving the first passage uncovered.  
         [0009]     In another embodiment of the present invention there is provided a method of harvesting grain from a plurality of plots separated by alleyways comprising the steps of: (a) passing a combine through a first plot, the combine including a header comprising a feederhouse assembly that is divided into at least first and second passages, a rotating auger, and a shiftable gate slidably mounted on the header aft of the auger and forward of the feederhouse, the gate being in a first position blocking access to the first passage; (b) shifting the gate from the first position to a second position upon reaching an alleyway separating the first plot from a second plot, the gate in the second position blocking access to the second passage and unblocking the first passage; (c) passing the combine through the second plot; and (d) repeating steps (a)-(c) a plurality of times.  
         [0010]     In yet another embodiment of the present invention there is provided in combination: a combine; and a combine header comprising a feederhouse assembly that is divided into at least first and second passages, a rotatable auger, and a shiftable gate slidably mounted on the header aft of the auger and forward of the feederhouse, the gate shiftable between a first position wherein the gate covers the first feederhouse passage so as to block access to the first passage and a second position wherein the gate covers the second passage leaving the first passage uncovered.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1  is a front perspective view of a two-row combine header in accordance with the present invention with the gate directing grain through the left side of the feederhouse assembly.  
         [0012]      FIG. 2  is a front perspective view of the combine header with the gate shifted for directing grain through the right side of the feederhouse assembly.  
         [0013]      FIG. 3  is a rear view of the header of  FIG. 1 .  
         [0014]      FIG. 4  is a front perspective view of the header of  FIG. 1  with the gate exploded forward.  
         [0015]      FIG. 5  is side cross-sectional view of the gate assembly.  
         [0016]      FIG. 6  is a front perspective view of a four-row combine header in accordance with the present invention with the gate in a first position.  
         [0017]      FIG. 7  is a rear perspective view of the combine header of  FIG. 6 .  
         [0018]      FIG. 8  is a rear perspective of the combine header with the gate shifted to a second position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]     The following description sets forth preferred combine headers and methods of harvesting grain plots using the headers in accordance with the present invention. It is to be understood, however, that these exemplary apparatus and methods are provided by way of illustration and nothing therein should be taken as a limitation upon the overall scope of the invention.  
         [0020]     Turning first to  FIG. 1 , there is provided a two-row combine header  10  comprising a feederhouse  12  and a horizontally shiftable shuttle gate  14 . Feederhouse  12 , used for transferring grain from the header  10  to threshing section of the combine, is divided into two functionally equivalent sections, or passages,  16  and  18  by partition  20 . By “functionally equivalent,” it is meant that both passages operate in approximately the same manner with approximately the same capacity. Various shafts  22 ,  24  related to the header or other combine operations may extend between sections  16  and  18  through orifices  26  (see,  FIG. 3  with the outer feederhouse housing removed for ease of illustration) formed in partition  20 . However, partition  20  effectively separates passages  16  and  18  so that harvested grain cannot cross over from one section to another.  
         [0021]     Gate  14  is slidably coupled to header  10  through bearing rod  28 . As shown in  FIG. 3 , gate  14  includes a pair of slide bearings  30  through which rod  28  passes. Bearings  30  are free to slide along rod  28  so that the position of gate  14  can be horizontally shifted relative to header  10 . Alternate methods of slidably attaching gate  14  to header  10  are contemplated and could be substituted for the system shown. For example, a roller and track system could be employed in place of the rod and bearing system shown. Gate  14  presents an opening  31  therein which is preferably sized and shaped so as to correspond with passages  16  and  18 .  
         [0022]     Gate  14  further includes a cylinder  32  for effecting horizontal movement of the gate relative to header  10 . Cylinder  32  is preferably hydraulicly actuated or can be operated by compressed air or any other means known to those skilled in the art. One end of cylinder  32  is fixedly attached to header  10  by bracket  34 , the opposite end is attached to gate  14  by bracket  36 . As shown in  FIG. 1 , gate  14  is positioned so that the gate opening  31  is aligned with feederhouse passage  18 . In this position, gate  14  allows the delivery of harvested grain to feederhouse passage  18  and effectively blocks all access to passage  16  so that substantially no harvested grain may enter. Cylinder  32  can be actuated to retract rod  37  thus causing gate  14  to shift to the position shown in  FIG. 2 . In this position, opening  31  is aligned with passage  16  thereby permitting harvested grain to be directed through passage  16  into the combine. Gate  14  then covers passage  18  prohibiting grain from entering. Gate opening  31  may be lined with a rubber or bristled seal that cooperates with partition  20  to ensure that no grain enters the blocked feederhouse passage.  
         [0023]     Header  10  also comprises a plurality of strips  38  that are placed in between the header and gate  14  to protect gate  14  and header  10  from wear caused by the shifting of the gate. As shown in  FIG. 5 , strips  38  engage the rear surface of gate  14  to facilitate horizontal sliding of the gate across header  10 . Strips  38  may be formed from any durable, resilient material such as plastic, rubber, or metal.  
         [0024]     A rotatable auger  40  is located forward of gate  14  and coupled therewith. Thus allowing the auger to be shifted with the gate to provide efficient feeding of grain to the appropriate feederhouse passage. Auger  40  is powered by drive section  42  which is mechanically coupled to the combine&#39;s main power source.  
         [0025]     Header  10 , as shown, is provided with two pairs of row units  44  particularly suited for harvesting row crops. However, it is within the scope of the present invention that header  10  be provided with a reel head or different kind of cutting table to harvest crops such as wheat.  
         [0026]     Header  10 , when attached to a combine, is particularly useful for harvesting multi-crop research plots. The combine for use with header  10  is also physically divided into separate compartments of equal functional capacity. This practice is often referred to as “splitting” a combine and comprises retrofitting a machine designed to harvest a single crop so that it is capable of harvesting two different varieties of grain at a single time without cross-contaminating either grain plot. This modification has typically been applied to either twin rotor systems, or single cylinder systems equipped with a four-row header. This modification involves physically separating the internal components of the combine. Once threshed in one of the separate combine compostrants, the grain can be packaged or immediately analyzed using on-board data collection equipment.  
         [0027]      FIG. 9  depicts a field containing several test plots  100 - 110 . The combine with header  10  attached begins harvesting plot  100  which comprises two substantially parallel rows of plants. The harvested grain is cut by row units  44  and delivered to the feederhouse  12  by auger  40 . Gate  14  is oriented so that gate opening  31  aligns with passage  16 . As the combine moves forward across plot  100 , all harvested grain is directed into passage  16 .  
         [0028]     After plot  100  is harvested, the combine enters alley  112 . Header  10  may be equipped with a sensor (not shown) that detects a condition, such as an interruption of incoming grain or the presence of a gap between plots, and causes cylinder  32  to be actuated thereby shifting gate  14  to a second position. Alternatively, the combine may employ a GPS system which causes gate  14  to shift at a predetermined location or the combine operator may manually actuates a control thereby causing gate  14  to shift to the second position. In this second position, gate opening  31  is aligned with feederhouse passage  18  and gate  14  blocks access to passage  16 , thus being in position to direct all harvested grain from plot  102  through passage  18  and into the corresponding compartment of the combine.  
         [0029]     The combine then enters plot  102  and begins harvesting grain and directing grain through passage  18 . Also, while harvesting grain from plot  102 , the combine finishes threshing the grain harvested from plot  100  and performs any packaging or on-board analysis thereof. Upon completion of harvesting plot  102 , the side of the combine corresponding to feederhouse passage  16  is ready to process additional grain. Therefore, when the combine enters another alleyway, gate  14  can be shifted back into the first position whereby opening  31  is once again aligned with passage  16  and access to passage  18  is blocked. While the next plot is harvested, the grain from plot  102  is threshed and analyzed or packaged. This process can continue indefinitely until the entire field is harvested.  
         [0030]     Header  10  allows for the combine to operate at a constant speed throughout the field without requiring stopping the forward progress thereof through the field, and without stopping the movement of any internal parts within the header or combine. This eliminates the need for clutches within the header to stop auger rotation and also avoids contamination risks by the build up of grain within the header.  
         [0031]      FIG. 6  depicts a four-row header  46  constructed in accordance with the present invention. Header  46  is similar in many respects to header  10  discusses previously, however, header  46  is configured to harvest two, two-row plots simultaneously instead of one, two-row plot. Header  46  generally comprises a feederhouse  48  that is divided into four passages  50   a - d  and a shuttle gate  52 . The housing to feederhouse  48  has been removed for ease of illustration. Header  46  is outfitted with four pairs of row units  54  and a partition  56  separating two pairs of row units  54  from the other two pairs of row units. Partition  56  is shown fixedly secured to the body of header  46 ; however, it may be possible to configure header  46  so as to secure partition  56  to gate  52  without interfering with the harvesting of grain by row units  54  as gate  52  is shifted. Auger  57  passes through partition  56  through an orifice in the partition.  
         [0032]     Gate  52  presents two rectangularly shaped openings  60  and  62  formed therein. As shown in  FIG. 6 , gate  52  is oriented so that opening  60  communicates with passage  50   b  and opening  62  communicates with passage  50   d.    FIG. 7  is a rear view of header  46  with gate  52  in the same orientation of  FIG. 6 .  FIG. 8  is a rear view of header  46  showing gate  52  shifted to a second position. In this second position, opening  60  now communicates with passage  50   a  and opening  62  now communicates with passage  50   c.  It is also within the scope of the invention to equip a combine with two independent gate and auger assemblies such as those illustrated in  FIGS. 1-4  thereby allowing for harvesting of four rows simultaneously.  
         [0033]     Harvesting with header  46  occurs much in the same fashion as with header  10 . However, header  46  can harvest plots  100  and  104  simulatneously, keeping grain harvested from each plot separate. Also, the combine used in connection with header  46  is split into four compartments for separately handling grain from up to four different plots. Upon reaching alleyway  112 , gate  52  is shifted, thus blocking access to the feederhouse passages and the corresponding combine compartments in which the grain from plots  100  and  104  is being processed. Plots  102  and  106  are then harvested and threshed in yet additional separate compartments within the combine.  
       EXAMPLE  
       [0034]     The following example provides a time savings comparison between a conventional method of harvesting a field of test plots and a method according to the present invention. Both the conventional harvester and a split combine including a two-row header according to the present invention are traveling at approximately 1.2 mph through the individual plots. Each plot presents a length of 17.5 ft., with the alley between plots measuring 2.5 ft. The distance between crop row centers is 30 in. Thus, the plot size (including the alley) is 100.0 sq. ft., giving approximately 435 plots per acre. Using a conventional harvesting method, the combine must pause for 15 seconds in the alley to ensure that grain from the previous plot has been completely processed. The combine equipped with the present header, does not need to pause in the alley and spends approximately 1.42 seconds therein.  
         [0035]     Table 1 shows the time savings using the header according to the present invention for a number of different acreage.  
                                                                       TABLE 1                                       Total Time (hours)                    Acres   Plots   Conventional   Shuttle header                            5   2175   16.4   6.8           10   4350   32.9   13.7           20   8700   65.9   27.4                      
 
 Harvesting with a split combine and the shuttle header of the present invention can be completed in approximately 60% less time than conventional harvesting methods.
A combine header is disclosed that comprises a shiftable gate which either permits or blocks passage of grain to a particular portion of the combine. The combine header allows for continuous harvesting of multicrop research and test plots without commingling different grain varieties.