Abstract:
A compact row unit positioning structure includes a gear and mating toothed surface to positively position agricultural row units on an implement. An electric or hydraulic motor may be used to drive the gear and move row units individually or in groups to change row spacings, follow rows or move row units to a maintenance position. In one embodiment, position sensing structure such a row finder or GPS device connected to a controller operates the positioning structure. Automatic on-the-go row alignment may be implemented, and various row spacings, skip-row patterns or repair access positions may be provided either manually or automatically.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to agricultural equipment with transversely adjustable working units supported from a frame and, more specifically, to structure for laterally adjusting the units on the frame. 
     BACKGROUND 
     Agricultural implements often include tools or row units that must be aligned relative to a row of crop or tillage or seeding area in a field. For example, currently available cotton harvesters include row units supported from a lift frame and transversely adjustable on the frame to change row spacings. If a skip row pattern of planting is employed, the units may have to be repositioned to line up with the rows. Examples of transversely adjustable a row units are shown in commonly assigned U.S. Pat. Nos. 4,803,830; 4,896,492 and 6,079,192. 
     In many of the adjustable arrangements, a friction interface propels the units in a specified direction. If the friction surfaces are wet or if the unit is under a heavy side load, friction between the roller and a support rail on the frame may be insufficient to transfer the rotary motion into a force significant enough to move the units in the desired direction. The driving sheave will simply spin and the unit will not move. 
     Other harvester row unit designs include use of a hydraulic cylinder or similar arrangement to move the row units laterally to follow the planted rows in the field. An example of hydraulic cylinder controlled transverse adjustment is shown in the aforementioned U.S. Pat. No. 6,079,192. Such designs typically are very large and present space constraint problems. In addition, alternate brackets and cylinder positions must be utilized for varying row spacings and for unit cleaning operations. 
     SUMMARY 
     A row unit positioning structure includes a drive sheave or gear and a mating surface with a geared interface on a lift frame to eliminate reliance on surface friction interaction to move row units. Additional gearing may be used to reduce the amount of torque necessary to provide transverse motion. The gearing may be located near the top or bottom of a support member such as a rail or rod or the like on which the row unit moves. If gearing is located below the support member, an independent roller supported from the lift frame bears a substantial portion of the weight of the row unit. A top mounted gearing may place a substantial portion of the row unit load on the drive sheave which includes the gear. The positioning structure may take the form of a rack and pinion arrangement. 
     An electric or hydraulic driving motor with a direct or indirect interface to the unit lift frame geared interface provides the necessary force for the transverse adjustments. The motor may be used to move the picking row units individually or in groups to follow the rows. An active, on-the-go adjusting structure may be easily implemented with the gearing. Reliance on friction between a roller and the support rail may be eliminated so that the units may be positively moved, even in wet conditions or when the harvester is on a slope. Gearing allows a reduction in the necessary torque input needed to relocate the units and may provide convenient position feedback with an electronic control. By using a motor and rotary motion to propel the units, the size of the mechanism may be reduced for better incorporation into areas with space restraints. For example, a drive motor may be placed over or under a support rail and may be directly attached to the unit hanger or mounting structure. Repositioning of the unit for different row spacings or for routine maintenance is easier because of the additional available space. 
     Automatic position control may be provided using a controller responsive to at least one of the following: 
     a) a harvester location signal dependent on harvester physical location, and row spacing information for the harvester physical location; 
     b) a row alignment signal from a row finder on the harvester; and 
     c) row spacing information entered into the position control structure. 
     These and other objects, features and advantages of the present invention will become apparent from the description below when taken with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is front perspective view of a cotton harvester header with transversely adjustable row units mounted on lift frame structure. 
         FIG. 2  is a rear perspective view of a portion of the header of  FIG. 1 . 
         FIG. 3  is an enlarged front perspective view of an adjustment mechanism for the header of  FIG. 1 . 
         FIG. 4  is a front view of an alternate embodiment of the adjustment mechanism. 
         FIG. 5  is a front view of a portion of an adjustment mechanism including a tapered upper support roller with positive gear tooth engagement. 
         FIG. 6  is an end view of the mechanism of  FIG. 5 . 
         FIG. 7  is a front view of an adjustable row unit with automatic positioning control. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1 and 2 , therein is shown a front portion of an implement such as a row harvester  10  which may be a cotton harvester header. The harvester  10  includes a transversely extending support or row unit lift frame  12  connected a conventional lift mechanism  14  supported from the front of a harvester frame (not shown). 
     A front rail  18  and a rear rail  20  mounted on or forming a portion of the lift frame  12  support a plurality of transversely adjustable row units  22  which may be aligned with rows of plants of various row patterns and row spacings. As shown, the row units  22  are cotton harvester row units. The row units  22  include transversely spaced front supports or hangers  28  and rear supports  30  which are carried by the front and rear rails  18  and  20 , respectively. As seen in  FIG. 3 , roller structure  38  connected near the top of the hangers  28  supports forward portion of each row unit  22  from the front rail  18 . The rear support  30  of each unit  22  includes a roller  40  carried on the rear rail  20 . The roller  30  and roller structure  38  support the row unit  22  from the lift frame and allow the unit to be moved transversely relative to the lift frame  12  to provide proper row alignment and facilitate movement of the units  22  for better access during inspection, maintenance and repair. 
     As shown in  FIG. 3 , front rail  18  includes a main transversely extending support member  46  and round bar, rod or tube  48  fixed to the top of the member  46 . The bar  48  projects from the member  46  and receives the roller structure  38  thereon. The roller structure  38  as shown in  FIG. 3  includes a pulley member or sheave  50  journalled for rotation about a fore-and-aft extending horizontal axis  50   a . Sides of the sheave  50  embrace the bar  48  to maintain the forward portion of the row unit  22  on the front rail  18  and prevent fore-and-aft movement of the row unit  22  relative to the lift frame  12 . Two roller structures  38  per unit maintain the row unit square with the lift frame  12  and, in combination with the rear support  30 , prevent the unit from tilting in the fore-and-aft direction relative to the lift frame  12 . 
     To provide positive positioning of the row unit  12  transversely on the rails  18  and  20 , a gear set or positive engagement meshing drive structure  60  such as a rack and pinion drive that converts rotary motion into linear motion is provided between the row unit  22  and the unit lift frame  12 . In one possible embodiment shown in  FIG. 3 , the meshing drive structure  60  includes an elongated gear-engaging member  62  or linear gear bar and a positive drive sheave or toothed gear  64  meshing with the gear-receiving member  62 . A drive  66  is operably connected to the drive sheave  64  for rotating the drive sheave  64  while the sheave engages the member  62  to thereby positively move the row unit  22  transversely relative to the lift frame  12  for alignment relative to a plant row or the like or for providing access to the unit  22  for inspection, maintenance and repair. 
     In the embodiment shown in  FIG. 3  the member  62  and the positive drive sheave  64  are located under the front rail  18  and therefore are not required to carry the weight of the row unit  22 . The drive  66  is shown as a shaft rotatably mounted by the hanger  28  and extending rearwardly therefrom to a connection with the drive sheave  64 . The drive  66  includes an end  68  which may receive a wrench, a crank or an electric or hydraulic motor or other suitable drive arrangement to rotate the sheave  64 . In addition in  FIG. 3 , indexing structure  70  is shown mounted for rotation with the drive  66  to secure the row unit  22  in a selected transverse position relative to the lift frame  12 . The indexing structure  70  may have an apertured disk  72  rotatable on a common axis with the sheave  64 . The disk  72  as shown has a disk circumference greater than the gear diameter of the sheave  64  and includes indexing apertures  74  spaced around the disk circumference. A spring-loaded locking pin  76  or other suitable locking device may inserted into an aligned aperture  74  when the row unit  22  is in the desired transverse position on the lift frame  12 . The pin prevents rotation of the indexing structure  70  and the drive sheave  64  to thereby lock the row unit in position on the frame  12 . The enlarged diameter disk  72  provides more closely spaced apertures  74  for more precise row unit location indexing and increases mechanical advantage of the locking mechanism for a more secure lock. 
     An alternate embodiment shown in  FIG. 4  is similar to that described above for  FIG. 3  but includes a drive motor  80  connected by bolts  82  to one of the hangers  28  at a location generally inward adjacent the hanger  28  above the top of the row unit  22 . The motor includes a powered drive output shaft  66 ′ which may be a direct motor output drive or gear reduction drive for increased torque. The motor  80  may be a hydraulic motor or an electric motor. The output shaft  66 ′ is connected to a gear  64 ′ which meshes with a mating toothed member  62 ′ located on the support member  46 . The motor  80  is powered by hydraulic or electric lines  84  connected via hydraulic or electric controller  86  to a source of hydraulic or electric power  88 . A controller input device  86 ′ may provide row unit position information by a variety of inputs including but not necessarily limited to manual operator input  90   a , row finder inputs  90   b  for on-the-go unit alignment, or real time GPS position or GPS field identification inputs  90   c . The input device  86 ′ may include a memory or reader for providing information to the controller  86  to automatically adjust row unit positions or spacings for a particular field or for an implement location within a field. For example, a custom harvester may store row spacing or skip-row pattern information for each customer, and this information can be used by the controller  86  to automatically move the row units  22  to the desired spacing or skip-row pattern just prior to beginning operation in a field. 
     Each row unit  22  may be controlled independently by a drive motor  80 , or two or more of the row units  22  may be tied together and controlled by a single drive motor  80 . The motor  80  may be of the type the prevents rotation of the drive shaft  66 ′ when unpowered so that the row unit  22  is locked in position automatically unless the controller  86  calls for transverse movement of the row unit  22 . An automatic braking mechanism may be employed. A row unit position feedback signal may be provided to the controller  86  from a detector via line  94  in any conventional manner including but not necessarily limited to gear tooth pulse detection and indices  96  located on the lift frame  12  or rails  18  or  20 . For manual input, the controller  86  may be tethered so that the operator may position the row units  22  remotely from the cab and may align locking structure  76 ′ with indexed aperture positions  76   a  on the main support  46 . 
     In the embodiment shown in  FIGS. 5 and 6 , roller structure  38   g  on the hanger  28  includes a sheave  50   g  with centrally located integral gear teeth  64   g  defining the gear and engaging mating teeth  48   t  on bar  48   g . In this embodiment, the gear teeth  64   g  may actually be part of the roller structure  38   g . As best seen in  FIG. 6 , the sides of the roller structure  38   g  are tapered and supported from angled surfaces on a rail  18   g . The teeth  48   t  project upwardly between the sides of the roller structure  38   g  into engagement with the teeth  64   g . A drive  66   g  is journalled in the upper end of the hanger  28  for rotation with the roller structure  38   g . A crank, wrench, or drive motor may be connected to the drive  66   g  to positively move the roller  38   g  and thus the row unit  22  transversely along the support member  46 . A single drive  66   g  per row unit  22  may be used, and the second roller structure  38   g  for the unit may simply provide support. 
     In the embodiment shown in  FIG. 7 , automatic row alignment structure  100  is shown wherein a row alignment signal from a row finder  102  at a row-receiving area  104  on the implement  10  provides a signal to a controller  86   r  via line  94 ′. The controller  86   r  is connected via line  84   r  to a motor  80   g  which, in turn, is connected to the drive  66   g . The motor  80   g  may be electric or hydraulic and may be a direct drive or a gear reduction motor. The controller  86   r  receives position signals from the row finder  102  and directs power from the source  88  to the motor  80   g  to turn the drive  66   g  to move the row unit  22  in the direction necessary to maintain the row-receiving area  104  aligned with the row. For example, if the row finder  102  moves to the right as shown in  FIG. 7  as a result of the row unit  22  being positioned too far to the left, an error signal sent to the controller  86   r  will cause the motor  80   g  to be powered to rotate the roller structure  66   g  in the clockwise direction to move the unit  22  to the right relative to the lift frame  12  until the error signal is at or near zero. 
     The mating gear set positive drive structure is described generally in the form of a rack and pinion, but it is to be understood that other types of positive drive actuators that convert rotational motion into linear motion could be used as well. Although described for a row unit of a cotton harvester, the present arrangement may be useful with other harvesting implements having adjustable row units, as well as other types of implements with working units that need to be adjusted transversely, including but not limited to planting and seeding implements, row crop tillage implements, strip tillage implements, and various sprayer and crop treatment implements. The gear set may also be located fore-and-aft relative to the rails, rather than above or below the rails. 
     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.