Abstract:
A planting unit for depositing fertilizer and seed in a single pass, double shoot manner includes a rotating disc that cuts a furrow in a planting surface and a trailing seed boot, having a cutting edge, that cuts a vertically and horizontally offset trench in the furrow to form a seed bed in the planting surface. The disc has a mounting frame for mounting the disc to a linkage assembly that is, in turn, coupled to a toolbar mount. The seed boot is also attached to the mounting frame. This common attachment provides a relatively short and compact device without sacrificing fertilizer and seed stratification.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a divisional of application Ser. No. 12/493,791 filed Jun. 29, 2009 now U.S. Pat. No. 8,215,247, which is a continuation-in-part of U.S. Ser. No. 12/266,310, filed Nov. 6, 2008, now U.S. Pat. No. 7,814,847. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to agricultural implements and, more particularly, to a seed boot for use with a disc opener that collectively provides a double-shoot, single pass deposition of fertilizer and seed onto a planting surface. 
     Fertilizer and seed are generally deposited onto a planting surface in either a single shoot or double shoot manner. With a single shoot planting technique, a mixture of seed and fertilizer is deposited into a single furrow and subsequently packed. With a double shoot planting technique, seed and fertilizer are deposited into separate furrows, which may or may not be closely spaced, and then packed. 
     A single shoot planting device typically has a single delivery hose through which the mixture of granular fertilizer and seed is delivered to the furrow. More particularly, a single shoot planting device will typically include a cutting tip that is dragged at a depth just below the planting surface. The delivery hose extends along a backside of the cutting tip, or knife, so that the fertilizer and seed mixture is deposited into the furrow immediately after the cutting tip cuts into the planting surface. Ideally, the mixture is deposited in to the furrow before the furrow collapses. The furrow is typically packed by a trailing packing or press wheel. 
     Another configuration of a single shoot planting device replaces the knife with a disc or coulter that rotates at an angle relative to a line of travel to form a furrow or trench in the planting surface. Because of the angling of the disc, the leading face of the disc pushes soil to one side and creates the furrow while the opposite, trailing face of the disc runs in the “shadow” of the leading face. The seed/fertilizer mixture is dropped to the bottom of the furrow while the furrow is held open by the disc and a cooperating plate (or scraper or seed boot) on the other side. The penetration depth of the disc controls the seed depth. A trailing packer wheel closes the furrow after the mixture is deposited and firms the planting surface (soil). 
     While single shoot planting units are less complex, it is generally preferred to use a double shoot planting unit which allows seed and fertilizer to be separately deposited into the furrow. When the fertilizer and seed are mixed, reduced concentrations of fertilizer must be used to prevent the seed from becoming damaged, i.e., “burnt”. In one exemplary double shoot planting unit, a knife has a side tip (side bander) that trails the leading knife as the planting unit is towed along the planting surface. The knife creates a furrow or fertilizer trench and the side bander forms a ledge in the sidewall of the furrow to effectively form a seed trench or seed bed. The fertilizer and seed trenches are separated from one another both horizontally and vertically. This separation provides a fertilizer/seed stratification that has been found to provide better growing conditions, i.e., higher concentrations of fertilizer may be used without seed “burning”. 
     In yet another type of double shoot planting unit a pair of rotating discs are used to form separate fertilizer and seed trenches having horizontal and vertical stratification. The leading disc cuts through the planting surface at an angle to cut a furrow or fertilizer trench. A trailing disc cuts through the side of the furrow formed by the leading disc to cut a seed trench that is generally horizontally and vertical offset from the fertilizer trench. U.S. Pat. No. 5,752,454 describes a dual disc, double shoot planting unit. 
     Dual disc units, such as that described in U.S. Pat. No. 5,752,454, are relatively complex structures with multiple rotating parts such as the discs themselves and associated bearings. This complexity also adds to the overall cost of the planting unit and the implement. Dual disc units, such as those described in the aforementioned patent, have also been found to perform unsatisfactorily in soft soil conditions. More particularly, the discs are generally angled to essentially “dig” into the soil surface to cut a furrow. Since the discs dig into the surface, less down pressure is needed. In harder soil conditions, the disc will effectively dig into the soil as the soil itself provides bias against which the disc can leverage. However, in soft soil conditions, the disc will essentially “plow” through the soil rather than cut an open furrow. Furthermore, to accommodate the space needed for two rotational elements, the distance between the leading and trailing discs is relatively substantial and can led to disturbance of the furrow before the seed is planted. That is, depending upon soil conditions, the furrow may collapse upon itself before the trailing disc cuts a seed bed into the furrow formed by the leading disc. The spacing between the discs also reduces seeding accuracy in rolling terrain, as well as adding to the overall size, weight, and cost of the carrying frame. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a planting unit for depositing fertilizer and seed in a single pass, double shoot manner in which a rotating disc cuts a furrow in a planting surface and a trailing seed boot, having a cutting edge, cuts a vertically and offset trench in the furrow to form a seed bed in the planting surface. The disc has a mounting frame for mounting the disc to a linkage assembly that is, in turn, coupled to a toolbar mount. The seed boot is also attached to the mounting frame. This common attachment provides a relatively short and compact device without sacrificing fertilizer and seed stratification. 
     In operation, the rotating disc, which sits at an angle relative to a line of travel, is pulled through the planting surface along the planting surface to cut a furrow into the planting surface. The furrow effectively defines a fertilizer trench into which fertilizer may be deposited from a fertilizer source through a fertilizer tube. The seed boot has a cutting edge that when pulled through the planting surface cuts a seeding trench in the furrow that is offset both vertically and horizontally from the fertilizer trench. Rearward of the cutting edge is a seed tube through which seed is passed and deposited into the seed trench. In one embodiment, a tab extends from a rearward edge of the seed tube that is designed to reduce the fall of seed into the fertilizer trench. In addition, the tab is also operative to reduce the ingress of soil or residue into the seed tube. 
     It is therefore an object of the invention to provide a planting unit that furrows a planting surface into separate fertilizer and seed trenches with minimal soil disturbance. 
     It is another object of the invention to provide fertilizer and seed stratification with a rotating disc and a seed boot having a cutting edge, wherein the seed boot and the rotating disc are coupled to a shared mount. 
     Therefore, in accordance with one aspect of the invention, a planting unit for use with a planting implement having a frame and configured to travel along a line of travel is disclosed. The planting unit has a disc mount configured to be coupled to the frame and a rotatable disc coupled to the disc mount and angled relative to the line of travel of the planting implement. The disc is configured to cut a furrow into a planting surface. A fertilizer tube is mounted to the disc mount and configured to deposit fertilizer into a fertilizer trench formed in the furrow. The planting unit further includes a seed boot coupled to the disc mount rearward of the fertilizer tube and the disc. The seed boot includes a hollow tubular member through which seed may be passed and deposited onto the planting surface, and a cutting edge configured to cut a ledge into the furrow onto which seed may be deposited. 
     In accordance with another aspect of the invention, a double-shoot, single pass implement for separately depositing fertilizer and seed with horizontal and vertical stratification onto a planting surface includes a toolbar configured to be coupled to a towing vehicle which is designed to pull the frame along the planting surface with a generally longitudinal line of travel. A plurality of disc openers are provided with each opener connected to the toolbar by a respective linkage assembly. Each disc opener includes a disc mount coupled to a corresponding linkage assembly and a rotatable disc mounted to the disc mount and configured to cut at an angle into the planting surface to form a fertilizer trench. A fertilizer tube is provided and is mounted to the disc mount generally adjacent the rotatable disc. Each opener also has a seed boot mounted to the disc mount and configured to cut a seed trench offset from the fertilizer trench. The seed boot includes a seed tube having a forward cutting edge and an outlet rearward of the fertilizer tube, and a tab connected to the seed tube generally opposite the forward cutting edge and extending rearward of the seed tube outlet. 
     According to yet another aspect of the invention, a furrowing and planting apparatus for use with an agricultural implement has a rotating disc configured to furrow a planting surface to define a fertilizer trench and a fertilizer source adapted to deposit fertilizer onto the fertilizer trench. The apparatus also has a seed boot disposed rearward of the rotating disc that includes a tubular member having a forward cutting edge that cuts a seed trench in the furrow. A deflector is mounted to a rearward edge of the seed boot and is operative to reduce the ingress of soil into the tubular member of the seed boot, particularly during roll back of the agricultural implement. 
     Other objects, features, aspects, and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout. 
       In the drawings: 
         FIG. 1  is a side elevation view of a planting unit according to one embodiment of the invention that includes a tool bar mount for coupling the planting unit to a toolbar of an agricultural implement; 
         FIG. 2  is a schematic view of the disc of the plating unit shown in  FIG. 1  shown relative to a furrow formed along a line of travel; 
         FIG. 3  is a bottom view of the planting unit shown in  FIG. 1 ; 
         FIG. 4  is a rear elevation view of the planting unit shown in  FIG. 1 ; 
         FIG. 5  is a rear elevation view of the planting unit shown in  FIG. 1  with a seed boot and packing system removed; 
         FIG. 6  is a partial exploded view of the planting unit shown in  FIG. 1 ; 
         FIG. 7  is an isometric view of the seed boot of the planting unit shown in  FIG. 1 ; 
         FIG. 8  is an end view of the seed boot shown in  FIG. 7 ; 
         FIG. 9  is an exploded view of the depth adjustment assembly of the planting unit shown in  FIG. 1 ; 
         FIG. 10  is an isometric view of a planting unit having a clamped on secondary seed boot according to another embodiment of the invention; 
         FIG. 11  is a side elevation view of a planting unit having a secondary seed boot clamped to a trailing arm according to a further embodiment of the invention; and 
         FIG. 12  is a side elevation view of a planting unit having a secondary seed boot fastened to a trailing arm according to yet another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is generally directed to a planting unit for us with an agricultural implement. While only one planting unit will be described, it is understood that the agricultural implement may include a plurality of such planting units 
       FIG. 1  shows a planting unit  10  according to one embodiment of the invention. The planting unit  10  generally includes a forward disc  12  that is angled relative to a line of travel. As known in the art, the forward disc  12  rotates about a center hub  14  to cut a furrow into the planting surface, S. A seed boot  16  is mounted rearward of the disc  12 , and as will be described, is designed to cut a seed trench into the furrow formed by the disc  12 . The disc  12  is coupled to a parallel linkage  18  by a disc mount  20  which has a mount arm  22  extending upwardly from the disc mount  20 . A trailing arm  24  is also coupled to the parallel linkage  18  and a press or packing wheel  26  is coupled to the trailing arm  24 . The press wheel  26  trails the disc  12  and the seed boot  16 , and as known in the art, applies a packing pressure to the furrow. The downward force is applied by spring  28 , but it is understood that other biasing devices may be used. In addition, the amount of downward force can be varied via lever  30  which has a selector member  32  that can be selectively positioned in one of a series of notches  34  of curved member  36 . 
     The parallel linkage  18  is also coupled to a toolbar mount  38  that is operative to couple the planting unit to a toolbar  40  of an agricultural implement. A hydraulic cylinder  42  is pivotably coupled to the toolbar mount  38  and the mount arm  22  by a bracket  44 , but it is understood other devices such as a spring or air bag could be used. The cylinder  42  is operative to apply a downward pressure on the disc  12  to force the disc  12  into contact with the planting surface. With additional reference to  FIG. 9 , the depth at which the disc  12  cuts into the planting surface is variably set by a gauge wheel  46  and a cooperating gauge wheel arm  48  and a control lever  50 . The control lever  50  controls the gauge wheel arm  48  by a crankshaft  52  that extends through the center of the disc  12 . The gauge wheel arm  48  is held in place by teeth  54  that interface with a mating fan shaped member  56 , which includes a series of notches  58  that individually define a different depth the disc  12  can be set via positioning of the control lever  50 . Various fasteners  57 , e.g., nuts, bearing  59 , washers  61  and seal  63  are used to secure the crankshaft  52  to the disc  12  via a hub  65  that is coupled to the disc  12  by fasteners  67 . 
     In addition to setting the depth at which the disc  12  cuts into the planting surface, the depth gauge wheel  46  keeps the outer surface of the disc  12  generally clear of mud and debris. A scraper blade  60  is mounted opposite the depth gauge wheel  46  is designed to remove dirt, mud, and other debris from the inner surface of the disc  12 . 
     The planting unit  10  is designed to separately drop fertilizer and seed into the furrow in a single pass. In this regard, a fertilizer tube  62  is mounted rearward of the center hub of the disc  12  but forward of the seed boot  16 . The seed boot  16  generally includes a seed tube  64  and a cutting member  66  that is forward of the seed tube  64 . In operation, as the disc  12  forms a furrow having a relatively deep fertilizer trench in the planting surface, fertilizer is dropped into the fertilizer trench from a fertilizer source (not shown) that communicates with the aforementioned fertilizer tube  62 . The cutting member  66  is offset from the disc  12  and cuts into a sidewall of the furrow to form a ledge or seed bed. Seed is then dropped via the seed tube  64  onto the ledge. The seed is fed to the seed tube  64  from a seed source in a known manner. 
     The cutting member  66  cuts into the sidewall of the furrow such that the ledge is offset horizontally and vertically from the fertilizer trench, i.e., bottom of the furrow. In this regard, the seed is deposited at a position that is spaced horizontally and vertically from the fertilizer that is dropped into the fertilizer trench. As noted above, it is generally preferred to plant seed and drop fertilizer into a furrow with stratification between the fertilizer and the seed. 
     In one preferred embodiment, the cutting member  66  is angled to lift the soil as the cutting member  66  is urged through the sidewall of the furrow. Thus, as the disc  12  and the cutting member  66  cut through the planting surface, the soil is temporarily displaced and lifted to form trenches for the deposition of fertilizer and seed. However, when disc  12  and the cutting member  66  pass, the soil will tend to fall back onto itself and effectively fill-in the furrow and thus the fertilizer and seed trenches. The press wheel  26 , which trails the seed boot  16 , then packs the fertilizer and the seed. Alternately, the cutting member  66  may be angled downward to force the soil down onto the fertilizer before the seed is deposited onto the seed bed. 
     In one preferred embodiment, a defector tab  68  extends from the backside of the seed tube  64 . The deflector tab  68  generally provides two separate functions. First, the deflector tab  68  is angled, as shown in  FIGS. 6 and 7 , as is the lower ends of the seed tube  64  and the cutting member  66 . With this angled orientation, the deflector tab  68  is operative to encourage seed toward the seed trench. Second, because of its proximity to the seed tube  64 , the deflector tab  68  reduces the ingress of soil and debris into the seed tube  64  during roll back of the planting unit  10 . 
     Referring now to  FIG. 2 , the disc  12  is angled relative to the furrow F that is formed by the disc  12  as it is rotated. The furrow F is formed generally in-line with the line of travel for the agricultural implement. The disc  12  is angled such that the angle formed between the leading edge  12   a  of the disc  12  and the line of travel, which generally bisects the furrow F, is approximately 7 degrees. While other angles are contemplated, it is generally preferred that the angle fall between 5 and 10 degrees, and more preferably between 6 and 8 degrees. It will be appreciated that while the disc is angled relative to the line of travel, the disc is normal to the plane of the planting surface. 
     Turning now to  FIGS. 3-5 , the fertilizer tube  62  is arranged such that the fertilizer falls generally centered in the furrow. The seed tube  64  has an outlet  70  that is angled generally rearward and laterally offset from the outlet (not numbered) of the fertilizer tube. As noted above, the seed trench is formed laterally offset from the fertilizer trench. This offset is formed because the seed boot  16  is generally angled away from disc  12 , as particularly shown in  FIG. 4 , such that the cutting member  66  forms a side bander. The angle defined between the leading edge  66   a  of the cutting member  66  and an axis transverse to the line of travel is preferably between approximately 5 to approximately 45 degrees. The depth of the seed tube outlet  70  is less than the lower most edge of the disc  12  and the seed tube outlet  70  is laterally offset from the disc  12  clearly illustrating the vertical and horizontal spacing of the fertilizer and seed trenches. 
     As shown in  FIGS. 6 and 7 , the seed boot  16  includes a header  72  that may be coupled to the disc mount  20  via fasteners  74 . Since the header  72  is mounted to the same mount  20  as the disc  12 , the combined assembly is relatively compact when compared to conventional double shoot, single pass planting units. 
     As shown in  FIG. 8 , the seed boot  16  is constructed such that seed tube outlet  70  sits behind the cutting member  66 . With this construction, the cutting member  66  cuts a ledge into the sidewall of the furrow and seed is placed onto the ledge as the seed drops through the seed tube outlet  70 . The cutting member  66  generally includes an angled cutting face  76  that in one embodiment includes a wear resistant insert  78 , such as a carbide insert. In one preferred embodiment, the seed tube  64  and the cutting member  66 , and its header  72  are formed as a single assembly. 
     As described above, in one embodiment, the seed boot  16  has a generally flat header  72  with mounting holes (not numbered) formed therein that align with mounting holes in the disc mount  20  and fasteners  74 , such as bolts, may be used to couple the seed boot  16  to the disc mount  20 . It is understood however that the seed boot  16  could be mounted to the disc mount  20  in other ways. For example, as shown in  FIG. 10 , a clamp  80  could be used. Similarly, as shown in  FIG. 11 , clamp  80  could be used to mount the seed boot  16  to the trailing arm  24  of the press wheel  26 . In yet another embodiment and referring to  FIG. 12 , holes (not shown) could be formed in the trailing arm  24  to allow the header  72  of the seed boot  16  to be fastened to the trailing arm  24  using fasteners  74  in a manner similar to the mounting to the disc mount  20  shown in  FIG. 6 . Whether by a clamp or by fasteners, mounting the seed boot  16  to the trailing arm  24  would allow the seed depth (the depth at which seed or other particulate matter is deposited from the seed boot  16 ) to be set by the press wheel  26 . It will be appreciated that clamps other than the types shown in the figures could be used to clamp the seed boot  16  to either the disc mount  20  or the trailing arm  24 . 
     The present invention provides a planting unit of relatively compact design in which a seed boot and a rotatable disc are mounted to the same disc mount. The seed boot has an angled cutting tip that cuts a ledge into the sidewall of a furrow formed by the rotatable disc. A seed tube rearward of the cutting tip deposits seed onto the ledge. A trailing press wheel then packs the fertilizer and seed. The ledge is cut vertically and horizontally spaced from the bottom of the furrow (fertilizer trench). In this regard, seed and fertilizer are deposited with vertical and horizontal stratification allowing higher concentrations of fertilizer to be used. In addition to providing a compact design, the present invention avoids the complexities associated with double shoot planting units that have multiple discs to cut fertilizer and seed trenches. In addition, the present invention provides less soil disturbance compared to conventional knife style double shoot, single pass planting units, especially when furrowing at faster speeds, e.g., greater than 5 m.p.h. 
     Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.