Abstract:
A seed drill planting apparatus includes an opener configured to plant a row of seeds at locations corresponding to the wing tips of the openers and a row of fertilizer at the center of the opener. The press wheels for the opener are constructed of a pair of skewed wheels that are arranged to throw soil inwardly to provide a proper cover for the rows of seeds and fertilizer placed into the ground by the opener. The skewed press wheels are connected to an adjusting mechanism that is operable to selectively vary the angle at which the press wheels are skewed with respect to the direction of travel. A one-way castering wheel is also provided to function to caster for tight turns on the side of the implement at the inside of the turn, but automatically locks into a stable position when the implement is converted into a transport position.

Description:
FIELD OF INVENTION 
   The present invention relates generally to planting apparatus for planting seeds in the ground in an agricultural environment. In particular, the present invention relates to a configuration of a planting apparatus for planting small grains in conjunction with an air seeder. 
   BACKGROUND OF THE INVENTION 
   With the increasing trend to minimum or zero tillage seeding practices, much work has been done in the design of a ground engaging tool. This tool must open the soil and provide an optimum placement for the seed, preferably maximizing moisture, consistent and accurate soil coverage, and adequate displacement of fertilizer. Those openers that provide a separation of seed and fertilizer are called “double shoot” openers, as these openers require a dual delivery system to maintain proper separation between the seed and the fertilizer. The double shoot opener design typically creates a separate groove within the furrow formed in the soil to accept the two commodities. With increasing amounts of fertilizer being applied during planting operations, and with the unpredictable fracturing of soils due to variations in moisture content and malleability, the seed is often comprised with too much contact with raw fertilizer, causing the seed to be burned and preventing the seed from germinating. 
   This problem has been addressed by manufactures of planting implements by providing an extra set of openers between every second seed row, placing seed, for example, at 10 inch row spacings and having two adjacent seed rows feed off a single fertilizer row between the two seed rows, thus assuring adequate separation between the seed and the fertilizer. This configuration of a fertilizer row between every second seed row is called “mid-row banding”. The seed rows are formed with furrows or grooves that are three to four inches for proper soil utilization and, as a result, there is significant soil disturbance. Furthermore, the rearmost rank of openers does not typically get as much “fall-back” of soil to cover the seed properly because there is no subsequent rank of openers that throw soil over to that row. This problem has also bee addressed by the installation of harrow tines that are operable to shift soil into the last formed seed row. With all of these openers and harrow tines, there is a substantial draft requirement for such an implement, requiring a substantially sized tractor to pull the implement. Furthermore, there is a significant loss of ground cover which contradicts the general principles of zero or low till planting operations. 
   Most shank-type seed drills are configured with three or four ranks of openers supported by wheels ahead of the front rank of openers and a row of press wheels behind the rear rank of openers. The distance between the wheels ahead of the front rank and the press wheels behind the rear rank is sufficiently large as to be subject to ground elevation irregularities that lead to inaccuracies in the depth at which the seeds are placed into the ground. Furthermore, the distance between the ranks of openers can cause misalignment when the drill slides to one side during side hill operations, often causing two seed rows to coincide and the press wheels to miss the row they were positioned to be packing. 
   Large implements of typical wing-up transport design are very bulky to transport over the public highways, interfering with other vehicular traffic and being jeopardized by overhead wires and highway overpasses. Accordingly, it would be desirable to provide an improved transport configuration for large implements to provide a more compact transport configuration without sacrificing operational requirements. 
   Accordingly, it is also desirable to provide a press wheel structure that are adjustable to vary the effect thereof for directing soil inwardly to cover seed rows. 
   SUMMARY OF THE INVENTION 
   Accordingly, an important object of the present invention is to provide an improved opener that provides proper separation between the rows of seeds being planted and the rows of fertilizer being placed into the ground. 
   It is another object of this invention to provide an improved press wheel apparatus to assure proper soil coverage of the seed rows during the planting operation. 
   It is a feature of this invention that the press wheels are formed by a pair of skewed wheels that direct soil inwardly as the wheels pass over the surface of the ground. 
   It is another feature of this invention that the skewed wheels are connected to an adjustment mechanism that is operable to vary the angle at which the press wheels are skewed with respect to the direction of travel. 
   It is an advantage of this invention that the adjustment in the skewing of the press wheels can very the amount of soil being thrown inwardly to cover the planted seed row. 
   It is still another object of this invention to provide an improved transport configuration for large tillage and planting implements. 
   It is still another feature of this invention that ground working tools are arranged on a common rockshaft that rotate from a working position to headland position wherein the press wheels are simply trailing and the implement boom carries the openers in an elevated position. 
   It is yet another feature of this invention that the trailing boom transport system retains a center group of openers without rotating into several vertical position. 
   It is still another advantage of this invention that the overall height of the implement in the transport position is not sufficiently high as to be jeopardized overpasses and overhead wires. 
   It is yet another object of this invention to provide a one-way castering wheel that will caster to allow tight turns, but lock in a stable position when the implement is converted into a transport position. 
   It is yet another advantage of this invention that the one-way castering wheels will automatically lock into a stable position when implement in converted into the transport position. 
   These and other objects, features, and advantages are accomplished according to the present invention by providing a seed drill planting apparatus including an opener configured to plant a row of seeds at locations corresponding to the wings tips of the openers and a row of fertilizer at the center of the opener. The press wheels for the opener are constructed of a pair of skewed wheels that are arranged to throw soil inwardly to provide a proper cover for the rows of seeds and fertilizer placed into the ground by the opener. The skewed press wheels are connected to an adjusting mechanism that is operable to selectively vary the angle at which the press wheels are skewed with respect to the direction of travel. A one-way castering wheel is also provided to function to caster for tight turns on the side if the implement at the inside of the turn, but automatically locks into a stable position when the implement is converted into a transport position. 
   The foregoing and other objects, features, and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description that follows, in conjunction with the accompanying sheets of drawings. It is be expressly understood, however, that the drawings are for illustrative purposes and are not to be construed as defining the limits of the invention. 

   
     BRIEF DESCRIPTION OF TH DRAWINGS 
     The advantage 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 top plain view of a drill incorporating the principles of the instant invention; 
       FIG. 2A  is an enlarged to plan view of a group of openers from the drill depicted  FIG. 1 ; 
       FIG. 2B  is a side elevational view of the group of openers depicted in  FIG. 2A ; 
       FIG. 3  is an enlarged top plan view of the drill depicted in  FIG. 1  but oriented into a adjustment mechanism for varying the skew angle of the individual press wheels; 
       FIG. 4  is a rear elevational view of the drill depicted in  FIG. 1  but oriented into a transport position with the openers placed into an elevated configuration; 
       FIG. 5A  is an enlarged side elevational view of the one-way caster wheel in the field operating position; 
       FIG. 5B  is a side elevational view of the one-way caster wheel similar to that of  FIG. 5A  but with the implement boom having been partially rotated toward the transport position; 
       FIG. 5C  is a side elevational view if the one-way caster wheel similar to that of  FIG. 5B  but with the implement boom having been fully rotated into the transport position; and 
       FIG. 6  is a top plan view if a large drill implement showing the castering movement of the one-way caster wheels at the ends of the implement wings. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIGS. 1-3 , a planting implement in the form of a small drill incorporation the principles of the present invention can best be seen. Any left and right references are used as a matter of convenience and are determined by standing at the rear of the implement and facing into the direction of travel. The implement  10  includes a frame  11  incorporating a hitch member  12  is adapted for connection to a prime mover, such as a conventional tractor (not shown). The hitch  12  is attached to the center boom  15  to define a transversely extending pivot axis  16  about which the center  15  is rotatable to move between transport and operation configurations. The center boom  15  is connected to left and right wing booms  17  by knuckle joints  18  that permit wing booms  17  to rotated relative to the center boom  15 . 
   Hydraulic cylinders  14  connect the center boom  15  to the A-frame-shaped hitch member  12  so that a retraction of the hydraulic cylinders  14  causes the center boom  15  and the wing booms  17  attached thereto to rotate about the transverse pivot axis  16 . Support wheels  13  are mounted on the hitch frame  12 , while wing support wheels  13   a  are mounted on the wing booms  17 , for support of the implement  10  for movement thereof over the surface of the ground. For stability of the booms  17 , draft links  19  connect the wing booms  17  to the hitch member  12 . 
   The openers  21  are arranged in groups or modules  20  of four openers  21  per module  20 . Each module  20  is connected to the boom  17  by a ball joint  23 , defining a universal pivot connection having a transversely extending axis, and a companion link  24   a  joining an anchor  24  in alignment with the transversely extending axis of the ball joint pivot  23  so that each of the modules  20  are free to oscillate about the corresponding ball joint  23  while remaining aligned with respect to a vertical pivot axis extending through the ball joint  23  as the modules  20  are operated through the field. 
   Each module  20  includes four openers  21  preferably in the form of conventional shanks  22  equipped with conventional spring rock protection (not shown). The press wheel assembly  25  is mounted on the end of a trailing arm  28  pivotally mounted to the module  20  by a horizontally extending pivot axis  29 . Each press wheel assembly  25  includes a pair of press wheels  26  that are supported for pivotal movement to define an adjustable skew angle for the individual wheels. In  FIG. 2A , the press wheel assemblies  25  are depicted in different skew angles as a matter of illustration. The skew angle of the rightmost press wheel assembly  25   a  is set at zero skew. Other possible skew angles are at 5 and 10 degrees of skew, as will be described in greater detail below. The greater the skew angle, the more aggressive the press wheel assembly  25  will operate to move soil to cover the planted seed in the furrows formed by the shanks  22 . 
   Each opener  20  also includes an evener  27  that is positioned transversely between each fore and aft corresponding pairs of shanks  22 . The eveners  27  are preferably in the form of a short bar pivotally attached to the cross tube  33  of the module  20  and provided with a roller  27   a  at each end thereof to engage the trailing arms  28  for each of the fore-and-aft pairs of press wheel assemblies  25 . The rollers  27   a  bear on the trailing arms  28  so that corresponding fore-and-aft pairs of trailing arms  28  can oscillate with changing ground elevations, but maintain an average depth for the shanks  22  served by the press wheel assemblies  25 . Thus, the module  20  is supported by the trailing press wheel assemblies  25  and the ball connection  23  with the boom  17 , as is best seen in  FIG. 2B . A link  31  joins the bell crank  32  to the cross tube  33  so that rotation of the adjustment crank  35  causes simultaneous rotation of the bell crank  32  and the cross tube  33  to which the eveners  27  are attached, causing an even depth adjustment of the module relative to the boom  17  and the press wheel assembly  25 . Two compression springs  36  link the boom  15 ,  17  to each end of the cross tube  33 . As the boom  15 ,  17  rotates the unit into the ground, the springs  36  are compressed to apply force in the form of the weight of the boom  17  to the module  20  for adequate ground penetration of the shanks  22  and the proper packing of the soil by the press wheel assemblies  25 . The module  20  is free to float about the ball joint  23  to permit the module  20  to follow ground contours. 
   The press wheel assemblies  25  are formed with an adjustment mechanism  40  that is coupled to the individual press wheels  26  to define the angle of skew of the press wheels  26 . Each press wheel  26  is mounted on a spindle unit  41  for rotation about a generally vertical axis to orient the press wheel  26  relative to the direction of travel. Each spindle unit  41  includes a stop member  42  formed in a curved shape and moveable with the press wheel  26 . Each stop member  42  is oriented above a position plate  46  having three holes  47  therein. A pin  45  is selectively positionable within one of the holes  47   a  which, when the curved stop member  42  moves into engagement with the pin  45 , sets the press wheel  26  at a ten degree skew angle. 
   The positioning of the pin  45  in the middle hole  44   b  sets the press wheels at a five degree angle, while the forwardmost hole  44   c  set a zero degree skew, or a straight ahead position. Each stop member  42  has a forward position  43  that also rotates with the press wheel  26  such that the forward portions  43  engage a central stop  44  when the press wheels  26  are set in the zero skew position, thus preventing the press wheels  26  from moving into a negative skew angle. Furthermore, the movement of implement  10  into a transport position, as will be described in greater detail below, places the press wheels  26  into the zero skew position irrespective if the location of the pin  45  because of the weight of the press wheels  26  and the offset position of the spindle axis  41  relative to the press wheels  26 . The central stop member  44  prevents the press wheels  26  from moving beyond the zero skew position. 
   The five degree skew position enhances the packing process as a result of a “smearing” action accomplished by the slightly skewed individual press wheels  26 , which also keeps the press wheels  26  free of mud. By adjusting the skew angle, the coverage of the soil over top of the seed rows can be tailored to suit the seed type and moisture conditions. Furthermore, the soil moved to the center of the opened soil path corresponding to the openers  21  to cover the fertilizer placed at the center of the path, as will be described in greater detail below, can be enhanced by more aggressive ten degree skew angle position, which is particularly important id anhydrous ammonia is used as the fertilizer. 
   Referring no to  FIG. 4 , the transport position of the implement  10  can best be seen. The booms  15 ,  17  are rotated by hydraulic cylinders (not shown) through a rotation of approximately 90 degrees forwardly to rotate the modules  20  from a normal generally horizontal working position, as depicted in  FIG. 1 , to a generally vertical transport position depicted in  FIG. 4 . The wing booms are then pivoted rearwardly about the knuckle joints  18  so that the modules  20  are then oriented to face each other as shown in  FIG. 4 . The rearward press wheel assembly  25  is permitted to rotate about the pivot connection  29  of the corresponding trailing arm  28  so as to fold downwardly, thus providing a compact transport position that is only approximately 8½ feet above the surface of the ground. Returning the implement  10  to the operating position will return the trailing press wheel assembly  25  to the normal position because gravity will rotate the corresponding trailing arm  28  about the pivot  29  to position the rear press wheel assembly  25  into an orientation to engage the ground and move rearwardly as the module  20  is lowered into a working position. 
   Referring now to  FIGS. 5A through 5C , the details of the one way caster wheel assembly  50  can best be seen. The wing boom  17  mounts a caster wheel assembly  50  at the remote outer end thereof to support the wing boom  17  above the surface of the ground. The wing boom  17  mounts the upper leg member  52  of the caster wheel assembly  50  in a fixed position. A lower leg member  54  of the caster wheel assembly  50  is attached to the upper leg member  52  by a pivot  53  defining a generally horizontal, longitudinally extending pivot axis when the implement  10  is in the normal working configuration, as depicted in  FIG. 5A . A hydraulic cylinder  57  maintains the orientation of the lower leg member  54  relative to the upper leg member  52  with respect to the pivot  53 . The caster wheel  51  is mounted on a mounting bracket  56  which, in turn, is pivotally attached to the lower leg member  54  by a pivot  55  defining an offset pivot axis that is generally vertical when the implement  10  is in the operating position of  FIG. 5A , but offset from the axis of rotation of the wheel  51 . In this normal operating configuration, the caster wheel  51  is free to rotate about the pivot mechanism  55  when the caster wheel  51  is on the inside of a turn, which is depicted in  FIG. 6 , to help the implement  10  corner around a turn. The position of the lower leg member  54  blocks the pivotal movement of the mounting bracket  56  when the caster wheel assembly  50  becomes the outside wheel on a turn of the implement  10 . 
   As the implement  10  has been converted into the transport configuration, the boom  17  is rotated through 90 degrees to position the pivot  53  so that the axis thereof is now generally vertical, as depicted in  FIGS. 5B and 5C , and the pivot  55  is re-oriented into a generally horizontal position. The caster wheel  51  can no longer move about the pivot  55  to effect a castering movement, thus causing the wheel  51  to become a fixed support wheel. The hydraulic cylinder  57  can be activated when the boom  15 ,  17  has been rotated into the transport configuration to pivot the lower leg member  54  relative to the upper leg member  52  through the pivot  53  to re-orient the wheel  51  into a position that will facilitate the re-positioning of the wing booms  17  into a rearwardly extending transport position. 
   In  FIG. 6 , a large implement  10  is depicted in which the center boom  15  is larger than in the configuration of the implement  10  depicted in  FIG. 1 . In the large implement  10  of  FIG. 6 , the center boom  15  is provided with a module  60  to span the gap between the modules  20  on the inner ends of the opposing wing booms  17 . The re-configuration of this large implement  10  into a transport position is substantially identical to that described above with respect to  FIG. 4 , except that the module  60  on the center boom  15  is connected to the center boom  15  by a pivot  62  so that the center module  60  remains horizontal when the boom cylinders  14  rotate the booms  15 ,  17  into the transport configuration. The horizontal orientation of the center module  60  when in the transport position enables the modules  20  on the wing booms  17  to be positioned over top of the center module  60  without interference therebetween. 
   In general, the above-described implement  10  utilizes a typical cultivator sweep as an opener  21  on the shanks  22  to open the soil wide enough to create two seed rows at the desired transverse spacing. In the way of an example, an 11 inch sweep will create an opening sufficiently wide to accommodate 10 inch row spacings with seed delivery tubes to direct seed into two properly spaced rows underneath the sweep  21 , one under each wing of the sweep. A separate delivery tube can then be positioned at the center of the sweep  21  to provide a fertilizer row at 20 inch centers to feed the two seed rows to either side thereof. Therefore, a module  20  having sweeps  21  mounted on 20 inch centers will be operable to provide 10 inch seed row spacing with alternate fertilizer rows on 20 inch spacings located no more than 5 inches from any seed row. If complete mechanical weed kill is required by the operator, a 22 inch sweep  21  can be utilized to provide complete ground coverage of the modules  20 . 
   Depth control for each sweep  21  is accomplished by the rear trailing packer wheel assemblies  25 . Mid-row banding of fertilizer can be accomplished with the above-described implement  10  with one-third of the number of openers  21  that are conventionally required to accomplish such an operation. With fewer openers  21 , the draft load of the implement  10  is lower and wider implement configurations are made possible. In fact, wider implements  10  are facilitated due to the simplicity of the implement design. Instead of the typical wing fold transport configuration, other folding configurations can be utilized because of the frame depth of the modules  20  is minimal and a substantial amount of torque to effect a rolling of the booms and rock shafts is not required. 
   The invention of this application has been described above both generically and with regard to specific embodiments. Although the invention has been set forth in what is believed to be the preferred embodiments, a wide variety of alternatives known to those of skill in the art can be selected within the generic disclosure. The invention is not otherwise limited, except for the recitation of the claims set forth below.