Abstract:
A tandem spindle drum row unit arrangement includes a rotary knife offset ahead of the forward drum to sever plants. A feeder rotor with fingers projecting through grid bar structure gently directs plants laterally into a standing row prior to substantial engagement by the spindles on the forward drum. Feeder column rotational speed is synchronized with ground speed. The knife, having a common axis with the rotor, operates at a higher speed for an efficient cut. The feeder column includes curved fingers which project through vertically spaced bars on a guard assembly to positively separate the plant from the fingers. The feeder column and rotary knife are driven through separate slip clutches. A kicker wheel between the drums moves plant material rearwardly.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to agricultural harvesters and, more specifically, to a harvester for removing crop from adjacent, closely spaced rows of plants. 
     BACKGROUND OF THE INVENTION 
     Harvesters such as cotton pickers include row units having upright picker drums with spindles projecting into a row receiving area to remove cotton from a row of plants. Harvesting very narrowly spaced rows of cotton has been a continuing source of difficulty. Cotton picker units such as shown in commonly assigned U.S. Pat. No. 4,821,497 with picker drums supported in tandem on one side only of the row or nested row harvesting units as shown in U.S. Pat. No. 4,538,403 have provided row harvesting capability for some narrow row spacings, but the reduction has not been sufficient to accommodate very narrowly spaced rows of fifteen inches or less. In some areas the rows may be spaced as closely as twelve inches (30 cm), and harvesting with conventional row units can result in substantial adjacent row plant damage and cotton loss. Cotton strippers with comb style heads often are used for removing cotton from narrowly spaced plants, but such heads are relatively inefficient and fail to effectively separate cotton and trash. 
     In commonly assigned U.S. Pat. No. 6,212,864 filed May 28, 1999 and entitled NARROW ROW COTTON HARVESTER, a crop severing and conveying attachment is described for cutting a row of plants and moving the plants into an adjacent standing row prior to contact by a forward spindle drum. The cut plants intertwine with the standing row so the picking drums can remove cotton from both rows of plants. Although the attachment is capable of harvesting rows spaced apart fifteen inches or less, the cutter as shown therein is offset forwardly from the drums a considerable distance. The plants must be supported well to keep them upright as they move diagonally rearwardly into the adjacent standing row, and the system requires a relatively long belt conveyer and cutter drive system. The front of the attachment extends forwardly beyond the row unit thereby substantially increasing the operating length of the harvester. 
     In commonly assigned and copending U.S. application Ser. No. 09/436,330 filed Nov. 8, 1999 and entitled NARROW ROW HARVESTER, now U.S. Pat. No. 6,293,078, another narrow row system is described wherein the spindles of a forward drum provide both a lateral transporting function for a severed row of cotton and a cotton removal function for the severed row and an adjacent standing row of cotton. The lateral speed of the spindles is relatively high at point of contact with the severed plant. Therefore, the spindle transport function is aggressive and increases drum loading and wear. The high lateral speed of the spindles in the transport area also results in cotton plant disorientation and cotton loss. A rotating column, which is located ahead of the drum to assist in lateral movement of the severed plants, frequently wraps with plant material which is carried around with the column. A plant cutter which rotates at the same speed as the column to sever the cotton plants rotates too slowly for optimum cutting when the column is rotating at the desired plant transporting speed. 
     BRIEF SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide an improved harvester row unit for harvesting crops planted in narrowly spaced rows. It is a further object to provide such a unit which overcomes most or all of the aforementioned problems. 
     It is a further object to provide such an improved harvester row unit for harvesting narrowly spaced rows of plants which severs plants offset from the row receiving area and moves the severed plants laterally into the row receiving area for contact with the spindles of a picker drum. It is another object to provide such a unit having reduced drum loading and wear compared to units wherein the spindles of the drum provide a substantial portion of the severed plant transverse conveying function. 
     It is another object of the present invention to provide an improved cotton picker row unit for simultaneously harvesting two narrowly spaced rows of cotton. It is a further object to provide such a row unit having a picking spindle drum for harvesting cotton from the two rows wherein the drum has at most only a minimal lateral transport function. It is yet another object to provide such row unit having improved cutting and lateral conveying characteristic and reduced drum loading and spindle wear. 
     It is still a further object to provide a cotton harvester row unit for harvesting narrowly spaced plants, and wherein the unit has an improved plant severing and transport system. It is another object to provide such a system having an improved drive arrangement which optimizes cutting efficiency and transport of severed plants into alignment with the spindle engagement area or crop removal zone of the unit. 
     It is another object to provide an improved harvester row unit capable of efficiently harvesting narrowly spaced cotton plants. It is a further object to provide such a unit particularly useful for harvesting rows of cotton plants spaced twelve to eighteen inches (30-45 cm.) apart. It is another object to provide such a unit for accommodating two adjacent rows of cotton wherein one of the rows is severed and moved laterally by feeder structure driven from the row unit drive structure. It is a further object to provide such a unit wherein the feed structure is synchronized with ground speed while the severing device is rotated at a higher speed. 
     A narrow row harvesting unit is described which is particularly useful for harvesting cotton plants in narrowly spaced rows. The crop removing portion of the unit includes a tandem spindle drum arrangement defining a main crop removing zone aligned with a standing row of cotton plants. A rotary knife offset ahead of the forward drum severs plants adjacent the row, and a feeder rotor or column with plant engaging projections rotates on a common axis with the rotary knife to gently direct the severed plants laterally between grid structure toward the crop removing zone and into the standing row prior to substantial engagement by the spindles on the forward drum. The rotary knife and feeder column are driven on the common axis from the row unit drive so the feeder column speed is synchronized with ground speed. The knife operates at a higher speed than the feeder to efficiently sever the plants and provide a clean cut. The feeder column includes fingers having a curved profile and projecting through vertically spaced bars of the grid structure to provide positive separation of the plant from the fingers. Plant carry-around by the feeder column is eliminated. Horizontal ribs located opposite the feeder column help keep the plants in contact with the fingers. The feeder column and rotary knife each are driven through a separate slip clutch for better protection. Kicker wheel structure located between the tandem drums moves plant material rearwardly in the zone. In one embodiment, the kicker wheel structure is located between the drums on the same side of the row as the drums to provide a compact package and facilitate kicker wheel drive. 
    
    
     These and other objects, features and advantages of the present invention will become apparent to one skilled in the art upon reading the following detailed description in view of the drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a cotton harvester having row units for harvesting closely spaced rows of cotton plants. 
     FIG. 2 is an enlarged top front perspective view of one of the row units on the harvester of FIG. 1 with portions removed to better show the severing, feeding and cotton removing structure and the drive structure of the unit. 
     FIG. 3 is an enlarged top view of the row unit of FIG. 2 with parts removed to better show the feed paths of adjacent narrowly spaced cotton plants. 
     FIG. 4 is an enlarged side view of a portion of the rotary knife and feeder column drives with portions removed to better show the individual slip clutches for the drives. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, therein is shown a cotton harvester  10  including a main frame  12  supported for forward movement over a field of plants to be harvested by forward drive wheels  14  and rear steerable wheels  16 . Transversely spaced multiple row harvesting units  20  are supported from the forward end of the frame  12  by one or more conventional hydraulically controlled lift structures  22 . The row units remove cotton from rows of the plants, and an air duct system  26  directs the removed cotton rearwardly and upwardly into a basket  28 . Although the row units  20  are shown mounted on a self-propelled harvester, it is to be understood that they can also be attached to a tractor in a conventional tractor mounted configuration. 
     The row unit  20  includes a forward frame assembly  30  supporting stalk lifter structure  32  which helps to guide closely spaced, adjacent rows of plants (R 1  and R 2 ) into the unit. A height sensing shoe assembly  40  is supported from the frame assembly  30  and controls the lift control structure  22  to maintain the unit  20  at a generally constant height above the ground during field operations as ground and surface conditions vary. 
     The row unit  20  includes a framed row unit housing  50  supporting a tandem drum arrangement  52  (FIG. 3) generally of the type shown and described in the aforementioned U.S. Pat. No. 4,821,497. The arrangement  52  includes forward and rearward spindle drums  54  and  56  supported for rotation (in the counter clockwise direction as shown in FIGS. 2 &amp; 3) about upright axes  54   a  and  56   a  which are generally aligned in the fore and aft direction. Drive structure  78  rotates the spindle drums  54  and  56  at a speed synchronized with the forward speed of the harvester  10 . Spindles  60  and  62  which are rotated about their axes project into a cotton removal or harvest zone  66  through grid bars  70  and  72  to remove cotton from the cotton plants passing rearwardly through the zone  66  between the bars and a pressure plate  74 . The synchronized drive assures the spindles have approximately a zero velocity relative to the plants moving rearwardly through the zone  66 . The cotton is then doffed from the spindles by conventional upright doffer columns (not shown) and moved rearwardly through a door structure  79  for delivery to the basket  28  by the air system  26 . 
     As best seen in FIG. 3, the harvest zone  66  is aligned with a row-receiving area for receiving a row R 1  of cotton plants. As shown, second and third rows of plants R 2  and R 3  are each spaced from the first row R 1  on the order of twelve inches (30 cm). As can be appreciated from FIG. 3, the row spacing is insufficient to accommodate additional harvesting drums for one of the additional rows without interfering with an adjacent row. To facilitate harvesting of an additional row (R 2  as shown in FIG.  3 ), cutting and feeding structure  80  and spaced guide or grid structure  82  are provided forwardly of the leading drum  54  to sever the row of plants R 2  and gently guide the severed plants into the standing row R 1 . The grid structure  82  prevents substantial contact of the severed plants by the spindles  60  until the plants closely approach a position aligned with the harvest zone  66 . The grid structure  82  also prevents plant wrapping in the structure  80 . As the standing row R 1  intermingled with the cut plants from the row R 2  pass rearwardly through the zone  66 , the rotating spindles  60  and  62  project into the plants and remove the cotton from the plants. Kicker wheel structure  90  partially projecting through the pressure plate  74  helps move plant material rearwardly through the zone  66 . 
     The stalk lifter structure  32  of the row unit  20  includes a central lifter assembly  92  which is adapted to run between the rows R 1  and R 2  and which is generally centered with respect to the drum axes  54   a  and  56   a . A similar lifter assembly  94  is located outwardly of the row R 1  and inwardly adjacent the next outermost row R 4 . The assemblies  92  and  94  are offset forwardly of the drum  54  to accommodate the cutting and feeding structure  80  and the grid structure  82 . Upright plant guide structure  96  angles outwardly in the forward direction F from a location on the opposite side of the row unit  20  adjacent the forward drum  54  to facilitate guidance of the row R 1  into the harvest zone  66 . 
     The cutting and feeding structure  80  includes an upright feeder  100  supported for rotation about an upright axis  100   a  between a floor panel  102  and a top panel  104 . The feeder  100  includes a hollow support shaft  106  connected to the drive structure  78  for rotation about the axis  100   a  at a speed synchronized with the forward speed of the harvester  10 . A cutter drive shaft  110  is supported for rotation about the axis  100   a  within the hollow support shaft  106  and extends through the floor panel  102  to a connection with a star-shaped cutter  114  (FIG.  3 ). The drive shaft  110  is also connected to the drive structure  78  for rotating the cutter  114  about the axis  100   a  at a speed substantially greater than the speed of the feeding structure  80 . The cutter  114  includes reversible cutting blades  118  with beveled leading edges which rotate (clockwise as shown in FIGS. 2 and 3) adjacent an angled shear plate  120  to sever the plants above the ground at a location centered between and adjacent the rear of the stalk lifter assemblies  92  and  94 . 
     The guide or grid structure  82  includes first and second spaced upright guides or grids  132  and  134  defining a plant path  136  which extends rearwardly and laterally inwardly toward the harvest zone  66 . The first grid  132  extends outwardly from the lifter assembly  92  and curves rearwardly and inwardly around the axis  100   a  to a termination with upright plant guide structure  138  adjacent the zone  66 . The second grid  134  extends rearwardly and inwardly from the lifter assembly  94  to a central location  140  where the spindles  60  begin to project through the grid. The location  140  is offset beyond the location wherein the spindles  60  have high acceleration rates to reduce spindle loading and prevent overly aggressive lateral plant transport by the drum  54 . The second grid curves inwardly and rearwardly from the location  140  to the forward extremity of the forward drum grid bars  70  where the spindles  60  fully project into the standing row R 1  and into the plants from the cut row R 2  conveyed into the standing row. 
     The upright feeder  100  includes a plurality of vertically spaced feeder wheels  150  having rearwardly curved tines  152  projecting through the first grid  132  into the plant path  136  from a location forwardly of the shear plate  120  to a location  156  offset forwardly and slightly outwardly of the harvest zone  66 . As shown, four wheels  150 , each having six uniformly spaced tines  152 , are mounted for rotation with the support shaft  106  about the axis  100   a . The first grid  132  includes panels (FIG. 2) vertically spaced to define slots for receiving the tines therethrough. Opposite each of the wheels  150  is a horizontal rib  160  located slightly below the wheel and on the opposite side of the path. The outermost ends of the tines slightly overlap the innermost edges of the ribs  160  to assure positive engagement of the tines  152  with the plants in the row R 2  as the plants are severed and moved rearwardly and inwardly. The ribs  160  narrow in the downstream direction and terminate at a location generally aligned with the outside of the drums  54  and  56  (FIG.  3 ). 
     The drive structure  78  for the drums  54  and  56  is of conventional construction and provides drum speed generally matched to the forward speed of the harvester  10 . However, additional drive to the cutting and feeding structure  80  is provided through assembly drive  178  (FIGS. 2 and 4) which includes an idler gear  180  driven from the front drum portion of the drive structure  78 . The idler gear  180  drives a first gear  182  (FIG. 4) which in turn meshes with and drives a second gear  184 . A first slip clutch assembly  190  is driven by the gear  182  and includes a drive gear  192  meshing with a driven gear  196  connected to the feeder wheel support shaft  106  for rotation of the feeder  100  at a speed synchronized with the forward speed of the harvester  10 . The second gear  184  is connected through a second slip clutch assembly  200  to the cutter drive shaft  110  for rotation of the cutter  114  at a speed substantially greater than the speed of the feeder  100 . Preferably, the RPM of the cutter  114  is approximately twice that of the feeder  100 . As shown, with the harvester  10  operating at a typical forward speed, the feeder  100  will operate at approximately 200 RPM while the cutter  114  rotates at approximately 420 RPM. The central portions of the tines  152  are aligned with the centerline of the row R 2  and have a speed which is slightly greater than forward speed to keep the throat area of the feeder  100  slightly ahead of the incoming plants. The tip speed of the tines  152  is approximately 1.7 times the forward speed in the embodiment shown. 
     The kicker wheel structure  90  (FIGS. 2 and 3) includes a drive shaft  210  supported from the row unit housing  50  for rotation about an upright axis  210   a . A pair of vertically spaced kicker wheels  212  are connected to the shaft  210  for rotation about the axis  210   a , and each includes four rearwardly bent tines  214  which project through slots in the pressure plate  74  between the drums  54  and  56 . A gear  218  fixed to the upper end of the shaft  210  is driven from the drive structure  78  at a speed synchronized with the forward speed of the harvester  10 . The gear ratios are selected such that the radially outermost portion of the tines  214  travel at a speed substantially greater than the harvester speed. The centers of the tines  214  generally align with the centerline of the row R 1  when fully projecting through the plate  74 , and the speed at the central portion of the tine more closely approximates the forward speed of the harvester. However, the speed at the tine center is still slightly greater than ground speed to help move plant material rearwardly through the zone  66 . By way of example, it has been found that driving the wheels  212  at approximately 240 RPM so that the central portion of the tine moves rearwardly at a speed of approximately 1.1 times forward speed of the harvester  10  provides good helper action to keep the zone  66  clear. 
     As shown in the solid lines of FIG. 4, the kicker wheel axis  210  is located on the side of the row R 1  opposite the drums  54  and  56 . In an alternate embodiment (broken lines of FIG.  3 ), a more compact arrangement is provided by placing the kicker wheel  90 ′ on the drum side of the row R 1  and extending the grid bars  70  rearwardly towards the grid bars  72 . The rearwardly bent tines  214 ′ project through extensions  70   a  of the forward grid bars  70  into the zone  66 . 
     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.