Abstract:
A furrow opener is operable as part of a nonsingulating air seeder and includes a rotatable disc to open a furrow. The opener also includes a vented seed catch pan positioned adjacent one side of the disc. The catch pan is operably coupled to a seed conduit of the air seeder to receive seed in a pressurized air stream from the seed conduit. The catch pan presents a seed inlet configured to receive seed from the seed conduit, a seed outlet positioned to deposit the seed within the furrow, and an elongated chamber extending between the inlet and outlet. The catch pan presents multiple vents spaced between the inlet and outlet, with the vents allowing pressurized air flow to escape from the chamber to ambient without passing through the outlet.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    The present invention relates generally to air seeders. More specifically, embodiments of the present invention concern a non-singulating air seeder with a seed catch pan, soil firming element, and a floating scraper. 
         [0003]    2. Discussion of Prior Art 
         [0004]    Conventional no-till planting equipment includes a rotatable disc opener that opens a furrow while minimally disturbing stubble or other organic matter along the field. One type of drill used for no-till operations includes the air seeder. Air seeders include multiple opener units that are supplied with seed via a pneumatic seed-conveying system. Prior art no-till equipment are also often designed to provide various types of fertilizer placement. For instance, fertilizer can be applied by either top-dressing or banding techniques. Fertilizer banding is performed by placing fertilizer in the ground prior to planting (i.e., pre-plant banding), during planting, or after planting. Fertilizer can be applied using various application methods such as mid-row banding, paired row banding, or cross row feeding. 
         [0005]    Prior art air seeding equipment suffers from various limitations. For example, air seeders use high-velocity air to distribute seed through tubes to various openers. The high-velocity air, while providing efficient seed delivery, violently delivers seed to the opened furrow. Thus, seed is delivered at a velocity that causes imprecise seed placement within the furrow. Moreover, the air velocity can cause delivered seed to bounce out of the furrow entirely. Such imprecise seed placement causes plants to emerge at different times. Prior art air seeders are also deficient because air velocity cannot be controlled at different locations along the field. Furthermore, conventional air seeders are ineffective at simultaneously depositing seed and inoculant in powder form. 
       SUMMARY 
       [0006]    The following brief summary is provided to indicate the nature of the subject matter disclosed herein. While certain aspects of the present invention are described below, the summary is not intended to limit the scope of the present invention. 
         [0007]    Embodiments of the present invention provide an air seeder that does not suffer from the problems and limitations of the prior art air seeders set forth above. 
         [0008]    A first aspect of the present invention concerns a furrow opener operable as part of a nonsingulating air seeder. The furrow opener broadly includes a rotatable disc and a vented seed catch pan. The rotatable disc is operable to be pulled over ground in a forward direction to thereby open a furrow. The vented seed catch pan is positioned adjacent one side of the disc and is operable to insert seed in the furrow. The vented seed catch pan is configured to be operably coupled to a seed conduit of the air seeder to receive seed in a pressurized air flow from the seed conduit. The vented seed catch pan presents a seed inlet configured to receive seed from the seed conduit, a seed outlet positioned to deposit the seed within the furrow, and an elongated chamber extending between the inlet and outlet. The vented seed catch pan presents multiple vents spaced between the inlet and outlet. The vents are positioned between the inlet and outlet and thereby allow pressurized air flow to escape from the chamber to ambient without passing through the outlet. 
         [0009]    A second aspect of the present invention concerns a furrow opener operable as part of a nonsingulating air seeder to deposit seed distributed from a seed conduit of the air seeder by pressurized air flow. The furrow opener broadly includes a drawbar assembly, a rotatable disc, and a seed placement assembly. The rotatable disc is operable to be pulled over ground in a forward direction to thereby open a furrow. The seed placement assembly is supported by the drawbar assembly to one side of the disc and is operable to insert seed in the furrow. The seed placement assembly includes a vented seed catch pan and a soil firming element located adjacent the furrow. The vented seed catch pan is configured to be operably coupled to a lowermost end of the seed conduit. The firming element is located in front of the catch pan along the forward direction to form a seed bed that receives seed in the furrow. The furrow opener includes a fertilizer injector for discharging fertilizer into the furrow. The vented seed catch pan and said soil firming element are removable from the drawbar assembly so that the furrow opener is operable to provide fertilizer banding without simultaneous air seeding. 
         [0010]    Other aspects and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments and the accompanying drawing figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         [0011]    Preferred embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein: 
           [0012]      FIG. 1  is a right side elevation of a tractor pulling a two-gang air seeder and a fertilizer cart, with the air seeder including a plurality of single disc openers constructed in accordance with a first embodiment of the present invention; 
           [0013]      FIG. 2  is a right side elevation of one of the single disc openers shown in  FIG. 1 , with the single disc opener being attached to a tool bar of the air seeder; 
           [0014]      FIG. 3  is a fragmentary plan view of the air seeder shown in  FIG. 1 , showing the location of dedicated bands of fertilizer along each seed row; 
           [0015]      FIG. 4  is a front left perspective of the single disc opener shown in  FIG. 2 , with the opener including a drawbar assembly, disc assembly, fertilizer injector assembly, firming wheel assembly, closing wheel assembly, gauge wheel assembly, and floating placement assembly; 
           [0016]      FIG. 5  is a fragmentary front left perspective of the single disc opener shown in  FIGS. 2 and 4 , showing the disc assembly, fertilizer injector assembly, and floating placement assembly; 
           [0017]      FIG. 6  is a fragmentary front right perspective of the single disc opener shown in  FIGS. 2 ,  4 , and  5 , showing the drawbar assembly, fertilizer injector assembly, and floating placement assembly; 
           [0018]      FIG. 7  is a left side elevation of the single disc opener shown in FIGS.  2  and  4 - 6 ; 
           [0019]      FIG. 8  is a rear left perspective of the floating placement assembly and fertilizer injector assembly shown in FIGS.  2  and  4 - 7 , with a firming wedge, vented seed catch pan, frame mounting bracket, and spring being exploded from a support frame of the placement assembly; 
           [0020]      FIG. 9  is a fragmentary perspective of the disc assembly and floating placement assembly shown in FIGS.  2  and  4 - 7 , with the disc and floating placement assemblies being cross sectioned to show the installation of the spring between the frame mounting bracket and the support frame, with the support frame being in scraping engagement with the rotatable disc of disc assembly; 
           [0021]      FIG. 10  is a rear elevation of the frame mounting bracket and spring shown in  FIGS. 8 and 9 ; 
           [0022]      FIG. 11  is a side elevation of the frame mounting bracket shown in  FIGS. 8-10 ; 
           [0023]      FIG. 12  is a fragmentary bottom view of the disc assembly, support frame, firming wedge, and fertilizer injector assembly shown in FIGS.  2  and  4 - 7 ; 
           [0024]      FIG. 13  is a fragmentary rear elevation of the single disc opener shown in FIGS.  2  and  4 - 7 , showing the relative position of the vented seed catch pan, firming wedge, fertilizer injectors, and support frame relative to the rotatable disc as the single disc opener is moved through the ground so that the disc assembly can open a furrow, the fertilizer assembly can inject the fertilizer band at the bottom of the furrow, and the placement assembly can form the seed bed and deposit seed in the seed bed; 
           [0025]      FIG. 14  is a rear elevation of the furrow similar to  FIG. 13 , but showing the furrow after the opener has injected fertilizer and deposited seed, the firming wheel has pressed the seed into the seed bed, and the closing wheel has closed the furrow; 
           [0026]      FIG. 15  is a left rear perspective of the vented seed catch pan shown in FIGS.  2  and  4 - 7 , showing front and rear walls and side walls that cooperatively define a funnel section of the catch pan and a rearwardly declining section that depends from the funnel section, with the walls cooperatively presenting an inlet and outlet of the catch pan, and with the rear wall presenting a plurality of elongated rear vents that extend vertically between the inlet and outlet, and further showing the firming wedge in phantom lines; 
           [0027]      FIG. 16  is a right front perspective of the vented seed catch pan shown in  FIG. 15 , showing the front wall presenting a plurality of elongated front vents that extend vertically between the inlet and outlet; and further showing the firming wedge in phantom lines; 
           [0028]      FIG. 17  is a left rear perspective of an alternative vented seed catch pan constructed in accordance with a second embodiment of the present invention, showing front and rear walls and side walls that cooperatively define an alternative funnel section and an alternative rearwardly declining section that depends from the funnel section, with the walls cooperatively presenting an inlet and outlet of the alternative catch pan, and with the rear wall presenting a plurality of alternative rear vents that extend vertically between the inlet and outlet; and 
           [0029]      FIG. 18  is a right front perspective of the alternative vented seed catch pan shown in  FIG. 17 , showing the front wall presenting a plurality of alternative front vents that extend vertically between the inlet and outlet. 
       
    
    
       [0030]    The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the preferred embodiment. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    Turning initially to  FIGS. 1-3 , an air seeder  20  and fertilizer cart  22  are pulled by a tractor T through a field G. The illustrated air seeder  20  and cart  22  are used to distribute seed and fertilizer along the field G, preferably as part of a no-till program that causes only minimal soil disturbance. As will be shown, the illustrated embodiment is particularly configured to adapt an air seeder for precise seed placement. The illustrated system is also preferably configured to inject nitrogen, phosphorus, sulfur, and zinc in a dual-shot application. However, the principles of the present invention are applicable to other seeding and/or fertilizer applications where a furrow is opened for placement of seed and/or fertilizer. The air seeder  20  and cart  22  are preferably pulled by tractor T, but could be pulled by another suitable powered vehicle. While the illustrated system is preferred for drilling of small grains, such as mustard, canola, or alfalfa, other grains such as wheat or garbanzo beans can be planted with the air seeder  20 . 
         [0032]    The illustrated seeder  20  is a two-gang, double-winged seeder configured to draw sixty-four openers  24  spaced on seven and one-half inch centers. However, as will be further described below, the layout of the plurality of openers  24  could be variously configured in any manner known in the art, including any alternative suitable numbers, spacing, and ranking of the openers. In one manner well known in the art, the seeder  20  includes a two gang, winged frame assembly  26  adjustably supported by a plurality of road wheels  28  and coupled to the tractor T by a floating hitch  30 . As will become apparent, virtually any conventional seeder could be modified with the inventive openers  24  described in detail below. One such seeder that could be modified according to the illustrated embodiment is the Case SDX air seeder, although the openers  24  could be incorporated into other seeding equipment. 
         [0033]    The seeder  20  further includes a seed tank  32  that holds seed S for planting and a hose  34  that delivers seed S from the tank  32  to openers  24 . As will be discussed, the seed S is directed from the tank  32 , via the hose  34 , to a seed tube of each opener  24 , and then to a vented catch pan. 
         [0034]    Turning to  FIGS. 2-4 , each opener  24  preferably includes a drawbar assembly  36 , a disc assembly  38 , a fertilizer injector assembly  40 , a firming wheel assembly  42 , a closing wheel assembly  44 , gauge wheel assembly  46 , and a floating placement assembly  48 . As will be discussed, a disc of disc assembly  38  is pulled by and urged into the field G by the drawbar assembly  36  in an operating position. The disc cuts through the field G to fracture the ground and create an elongated furrow F that is configured to receive seed and fertilizer. The floating placement assembly  48  is also configured to form a slot St within the furrow F. The slot St includes a generally flat shelf that receives seed S and extends alongside the furrow F. The opener  24  is preferably adjustable so that the bottom dead center location BDC of the disc can be moved to adjust the furrow depth. The illustrated opener  24  is preferably a right opener, with the rotatable disc generally angled to the right of the furrow F. However, the openers  24  could include left openers or a combination of left and right openers. 
         [0035]    Turning to  FIGS. 2-7 , the drawbar assembly  36  has a conventional construction that supports and positions the remaining opener components. The drawbar assembly  36  preferably includes a bracket  50 , arm  52 , and spring assembly  54 . The arm  50  is elongated and presents fore and aft ends  56 , 58 . As will be discussed, components of the disc assembly  38 , firming wheel assembly  42 , closing wheel assembly  44 , gauge wheel assembly  46 , and floating placement assembly  48  are attached along and supported by the arm  52 . The bracket  50  and arm  52  are preferably pivotally connected by a pin at a joint  60  adjacent the fore end  56  so that the arm  52  can pivot generally up and down about a lateral axis of the pin. The aft end  58  of arm  52  can pivot downwardly until a stop provided by the fore end  56  engages a stop provided by the bracket  50 . 
         [0036]    The spring assembly  54  includes a housing  62  and a spring  64  received on the housing  62 . The housing  62  includes opposite fore and aft ends  66 , 68 , with the fore end  66  being removably pivotally attached to the bracket  50  with a pin  70 . The aft end  68  includes a pin  72  that is removably received by brackets  74   a,b . The brackets  74  each include an open slot  76  that receives the pin  72 . The brackets  74  are each attached to the arm  52  between ends  56 , 58  with bolts. 
         [0037]    The openers  24  are supported by attaching the bracket  50  to a toolbar of the frame assembly  26 . With the fore end  56  of the arm  52  engaging the bracket  50 , the spring  64  is preferably compressed so that the spring force holds the arm  52  in an engagement position and causes the opener  24  to exert a yieldable downforce on the ground. As the arm  52  rotates generally upwardly out of the engagement position, the spring force increases progressively. In the usual manner, this construction permits the opener  24  to shift upwardly when the disc, or another part of the opener  24 , contacts a hard obstacle along the ground G (e.g., to minimize any damage to the opener  24  or another part of seeder  20 ). 
         [0038]    The disc assembly  38  is configured to open the furrow F and includes a rotatable disc  78  mounted on a shaft  80 . The shaft  80  is rotatably received by the arm  52  so that the disc  78  is rotatable, in the usual manner, about a shaft axis. The shaft  80  is positioned so that the disc  78  is preferably oriented with an oblique fixed disc angle between the disc  78  and a fore-and-aft travel axis of the opener  24  that ranges from about five (5) degrees to about seven (7) degrees. Furthermore, the shaft  80  may be positioned so that the disc  78  extends at an angle relative to vertical. Generally, the shaft  80  is also preferably mounted so that the disc  78  is restricted from sliding along the shaft axis. 
         [0039]    The gauge wheel assembly  46  is adjustable so that the bottom dead center BDC location of the disc  78  can be moved to adjust the depth D of furrow F (see  FIGS. 13 and 14 ). Again, the depth D preferably ranges between about one and one-half inches (1½) and about four and one-half (4½) inches and, more preferably, ranges between about three and three-quarters (3¾) inches and about four and one-half (4½) inches. Preferably, the disc  78  has an outermost diameter dimension of about 22.75 inches. Additionally, the disc  78  is preferably made of high-carbon steel with a Rockwell C-Scale Hardness of 50. As the disc  78  opens the furrow F, a zone of disturbed soil Z is created and trails the leading edge of the disc  78  (see  FIG. 14 ). The orientation of the disc  78  creates a shadow area SA behind the disc  78  as the disc  78  is pulled in the forward direction (see  FIG. 3 ). 
         [0040]    Turning to  FIGS. 4 and 7 , the firming wheel assembly  42  is pulled along seed bed SB to firmly press the seed S into the top soil along the seed bed SB (see  FIG. 2 ). The firming wheel assembly  42  includes an elongated arm  82 , firming wheel  84 , and a torsion spring  86 . The arm  82  is pivotally mounted adjacent a fore end thereof to the arm  52  with a firming wheel shaft. The wheel  84  is rotatably mounted to the arm  82  adjacent an aft end thereof. The spring  86  is mounted on the firming wheel shaft, with one of end of the spring  86  engaging a top edge of the arm  52  and the other end of the spring  86  engaging a top edge of the arm  82 . Thus, the spring  86  urges the firming wheel  84  downwardly into the field G. 
         [0041]    In the usual manner, the closing wheel assembly  44  is operable to return soil to the furrow F and thereby close the furrow F. The closing wheel assembly  44  includes an elongated arm  88 , closing wheel  90 , and a torsion spring  92 . The arm  88  is pivotally mounted adjacent a fore end thereof to the aft end  58  of the arm  52  with a closing wheel shaft. The wheel  90  is rotatably mounted to the arm  88  adjacent an aft end thereof. The spring  92  is mounted on the firming wheel shaft, with one of end of the spring  92  engaging an upright edge of the arm  52  (see  FIG. 4 ) and the other end of the spring  86  engaging a top edge of the arm  88  (see  FIG. 2 ). The spring  92  urges the closing wheel  90  downwardly into engagement with the field G. 
         [0042]    The gauge wheel assembly  46  is operable to maintain the height of the disc  78  (to control the furrow depth D) and the floating placement assembly  48  relative to field G. The gauge wheel assembly  46  includes a pivotal frame  94  pivotally mounted to the arm  52  with a pin  96 , a gauge wheel  98  rotatably mounted to the frame  94 , and a bracket  100 . The gauge wheel  98  is supported by the frame  94  so that the wheel  98  can be selectively vertically positioned relative to the remainder of the opener  24 . The bracket  100  is attached to the arm  52  adjacent the aft end  58  and presents a slot  102  and teeth  104  (see  FIGS. 4 and 7 ). The frame  94  includes a pin that slidably engages the slot  102 . A locking device  106  is attached to the frame  94  and selectively engages the teeth  104  to lock the frame  94  into one of multiple positions relative to the bracket  100  and thereby lock the gauge wheel  98  in a corresponding vertical position relative to the arm  52 . 
         [0043]    The drawbar assembly  36  brackets to one of the toolbars of the frame assembly  26  and thereby pulls the other components of the opener  14   b  behind the toolbar while yieldably biasing the components downwardly into firm engagement with the field G. The disc  78  of the disc assembly  38  is rotatably supported and engages the field G when in an operating position, i.e., when the gauge wheel  98  engages the ground G. When in the operating position, as the disc  78  is pulled in a forward direction (e.g., left-to-right as viewed in  FIG. 1  and in the direction of the arrow as shown in  FIG. 3 ), the disc  78  cuts through the field G thereby fracturing the ground and creating the elongated furrow F therein (see  FIGS. 11 and 12 ). The disc  78  is adjustable relative to the gauge wheel  98  to adjust the depth of the bottom dead center of the disc  78  relative to the surface of the ground G. In this manner, the depth of the furrow F, as controlled by the bottom dead center position of the disc  20 , can be adjusted to one of several different depth settings. Preferably, the depth ranges between about one and one-half (1½) inches and about four and one-half (4½) inches. As shown in  FIG. 13 , the leading edge of the disc  20  is angled relative to the forward direction of travel. 
         [0044]    Turning to  FIGS. 3-8 , the fertilizer injector assembly  40  is operable to place fertilizers N and P in a single, dedicated fertilizer band DB (see  FIG. 3 ). In particular, the fertilizer injector assembly  40  includes a generally wingless injector that provides precise placement of nutrients along a fertilizer bed FB along furrow F (see  FIG. 14 ). That is, the fertilizer injector assembly  40  preferably does not include an injector wing that creates the fertilizer bed. However, for some aspects of the present invention, the assembly  40  could include an injector wing. Features of a preferred injector wing are disclosed in U.S. Pat. No. 7,152,539, issued Dec. 26, 2006, entitled FERTILIZER INJECTOR WING FOR DISC OPENERS, which is hereby incorporated in its entirety by reference herein. The fertilizer injector assembly  40  preferably includes a toxic injector  108  and a non-toxic injector  110 . The injectors  108 , 110  include respective supply lines  112 , 114 , sheaths  116 , 118 , and nozzles  120 , 122  (see  FIGS. 5 and 6 ). 
         [0045]    The toxic fertilizer injector  108  injects the toxic fertilizer N, preferably in the form of anhydrous ammonia, into the bottom of furrow F. The supply line  112  fluidly communicates the nozzle  120  with a fertilizer tank  124  stored on the cart  22  (see  FIG. 1 ). In one manner known in the art, the illustrated tank  124  stores a quantity of anhydrous ammonia N (either gas or liquid) and delivers it through a manifold  126  disposed along the supply line  112  under a controlled pressure to the nozzle  120  where it is injected as liquid anhydrous ammonia N into the furrow F. The incorporated &#39;681 patent and &#39;049 patent (see below) disclose a suitable anhydrous ammonia delivery system including a manifold. The supply line  112  preferably includes a nylon-type line. Adjacent to nozzle  120 , the supply line  112  is preferably covered and protected by sheath  116 . 
         [0046]    The nozzle  120  of injector  108  includes a terminal orifice  120   a  that is configured to inject liquid anhydrous ammonia. In particular, the orifice  120   a  alters or maintains the pressure of the fertilizer N below and/or above the vapor pressure of the fertilizer N. Additional details of such a nozzle and orifice are disclosed in U.S. Pat. Nos. 6,360,681 and 6,283,049, both of which are hereby incorporated in their entire by reference herein. 
         [0047]    The non-toxic fertilizer injector  110  injects the non-toxic fertilizer P into the furrow F. The supply line  114  fluidly communicates the nozzle  122  with a fertilizer tank  128  stored on the tractor T (see  FIG. 1 ). In one manner known in the art, the illustrated tank  128  stores a quantity of fertilizer P and delivers it through a manifold  130  disposed along the supply line  114  under a controlled pressure to the nozzle  122  where it is injected into the furrow F. The supply line  114  preferably includes a nylon-type line. Adjacent to nozzle  122 , the supply line  114  is covered and protected by sheath  118 . 
         [0048]    The illustrated injector  110  is preferably configured to inject fertilizer P in the form of a blended mixture of liquid ammonium phosphate (APP) and liquid ammonium thiosulfate (ATS). In one manner known in the art, the nozzle  122  includes a terminal orifice  122   a  configured to inject the liquid APP/ATS mixture under pressure. The terminal orifice  122   a  preferably presents a larger cross-sectional area than the orifice  120   a  of the injector  108  to accommodate the different pressure requirements of the fertilizers N and P. 
         [0049]    In the illustrated arrangement, the nozzle  120  is positioned to trail the nozzle  122  and be inline therewith so as to place the fertilizers N and P in the single, dedicated fertilizer band DB (see  FIG. 3 ). The illustrated nozzles  120 , 122  are preferably attached to an aft end of and is thereby shiftable with the placement assembly  48 , although the nozzles could be alternatively supported behind the disc assembly. The nozzles  120 , 122  and the rear margin of the placement assembly  48  preferably present a banding width dimension BW that ranges from about one-half (0.5) inch to about one (1) inch and, more preferably, is about three-quarters (0.75) of an inch (see  FIG. 13 ). Consequently, the liquid APP/ATS mixture is injected in front of the liquid anhydrous ammonia application. The liquid anhydrous ammonia is injected at a high pressure and driven into the APP/ATS mixture to crystallize and form triammonium polyphosphate sulfate (TAPPS). It has been found that TAPPS is the most plant-available form of placed nitrogen, phosphorus, sulfur and zinc and is preferably formulated in the field. 
         [0050]    Turning to  FIGS. 4-14 , the floating placement assembly  48  precisely deposits fertilizer and seed along the furrow F. As will be discussed, the floating placement assembly  48  is preferably shiftably mounted on the arm  52  so as to operate as a scraper for the rotatable disc  78 . However, for some aspects of the present invention, the assembly  48  could be used to direct fertilizer and/or seed along the furrow F without engaging the disc  78 . The floating placement assembly  48  preferably includes a support assembly  132 , a firming wedge  134 , and a vented seed catch pan  136 . 
         [0051]    Turning to  FIGS. 5-8 , the support assembly  132  supports the injectors  108 , 110 , firming wedge  134 , and seed catch pan  136  adjacent the rotatable disc  78 . The support assembly  132  includes a support frame  138  with fore and aft plates  140 , 142  welded to one another along weld line  144 , a front lug  146  welded to the front end of plate  140 , inserts  148   a,b,c , and a wear rod  150 . As will be shown, the fore plate  140  is attached to the wear rod  150  and supports the wear rod  150  in engagement with disc  78  so that the wear rod  150  provides a leading edge of the support frame  138 . The aft plate  142  extends at an angle relative to the plane of fore plate  140 . The aft plate  142  supports the insert  148   c  and injectors  108 , 110 , and the aft plate  142  also serves to hold the furrow F open, as will be discussed below. Furthermore, the insert  148   c  provides a trailing edge of the support frame  138 . 
         [0052]    Preferably, the plates  140 , 142  have a thickness of one-quarter (¼) inch and are preferably made of A-36 carbon steel, although the plates  140 , 142  could include other materials and be alternatively sized. Inserts  148  comprise narrow, generally rectangular strips of material fixed to the plates  140 , 142 . The inserts  148  are preferably made of a very hard material so that the inserts  148  resist wear. Preferably, the inserts  148  include chrome or chrome carbide, but could include other materials. The inserts  148  are secured within corresponding slots presented by plates  140 , 142 . 
         [0053]    The wear rod  150  is preferably made of a material that is relatively soft compared to the material of disc  78 . More preferably, the wear rod  150  is made of “304” stainless steel with a Rockwell B-Scale hardness of 30. Preferably, the support frame  138  is substantially rigid so that the frame  138  can be used as a scraper for the rotatable disc  78 . However, for some aspects of the present invention, the frame  138  could be spaced from the disc  78 . The frame  138  is used as a scraper by slidably engaging the wear rod  150  with the surface of rotatable disc  78 , as will be described below. 
         [0054]    Turning to  FIGS. 5-11 , the support assembly  132  further includes a frame mounting bracket  152  and spring  154 . The bracket  152  includes a body with offset flanges  156 , 158  and a pin  160  welded to flange  158 . The illustrated bracket  152  is preferably secured to the arm  52  with threaded fasteners  162  that extend through the arm  52 , brackets  74 , and flange  156 . 
         [0055]    Turning to  FIGS. 8 and 9 , the bracket  152  and support frame  138  are preferably shiftably connected to one another to permit limited lateral shifting therebetween and thereby allow the support frame  138  to operate as a disc scraper to remove ground debris from the disc surface. The support frame  138  and bracket  152  are secured to one another with threaded fasteners  164 . The spring  154  is received on the pin  160  and is thereby positioned between the flange  158  and an upstanding tab  166  of the fore plate  140  (see  FIG. 9 ). The fasteners  164  extend through corresponding sets of holes  168   a,b  in the fore plate  140 . The set of holes  168   a  serve to position the support frame  138  in a rearward location relative to the arm  52 , while the set of holes  168   b  serve to position the support frame  138  in a forward location relative to the arm  52  (see  FIG. 8 ). 
         [0056]    The holes  168  are generally oversized relative to the size of fasteners  164  so that the holes  168  and fasteners  164  provide a joint  170  that allows some off-axis pivoting of the fasteners  164  within the holes  168  (see  FIG. 9 ). Furthermore, the fasteners  164  are secured so that the joint  170  permits some lateral movement of the fore plate  140  along the axis of fasteners  164 . With the fasteners  164  secured, the spring  154  urges the support frame  138  away from the flange  158 . Furthermore, the spring  154  generally urges a lower portion of fore plate  140  (i.e., below the fasteners  164 ) away from the arm  52 . 
         [0057]    The support assembly  132  also preferably includes an elastic rope  172 . The rope  172  preferably interconnects a lug  174  attached to the arm  52  and the front lug  146 . The illustrated lug  174  includes opposite perpendicular flanges, with one flange attached to the arm by fastener  162  and the other flange receiving a lug fastener  175  around which the rope  172  is secured under tension. In this manner, the rope  172  provides a spring element that urges the lug  146  toward the arm  52  and the lower portion of fore plate  140  away from the arm  52 . The rope  172  is adjustably tensioned by rotating the lug  174  about the lug fastener or by looping the rope  172  an additional turn about the lug  174 . Thus, the spring  154  and rope  172  cooperatively provide a spring force that urges the lower portion of plate  140  away from the arm  52  so that the wear rod  150  is generally forced into engagement with the rotatable disc  78 . However, for some aspects of the present invention, the support assembly  132  could be used without the elastic rope  172 , i.e., when the spring  154  provides adequate spring force to urge the wear rod  150  toward the rotatable disc  78 . Furthermore, the support assembly  132  could have an alternative spring mechanism to hold the wear rod  150  in engagement with the rotatable disc  78 . 
         [0058]    Generally, the support frame  138  is positioned so that an aft portion of wear rod  150  engages the rotatable disc  78 . In particular, a front end of wear rod  150  is spaced slightly from the rotatable disc  78 , and the wear rod  150  extends rearwardly toward a convergence location C of the frame  138  and the rotatable disc  78 . Thus, the wear rod  150  is positioned so that the wear rod  150  extends into engagement with the rotatable disc  78  along the aft portion, which extends forwardly of the convergence location C. Preferably, the convergence location C is preferably about two (2) inches behind the bottom dead center location BDC. Such positioning of the support frame  138  serves to locate the support frame  138  more centrally relative to the shadow area SA. In this manner, the illustrated configuration has been found to allow a trailing edge of the support frame  138  to remain in the furrow F while the opener  24  is turned through a relatively small-radius turn. In turn, it has been discovered that such a configuration minimizes wear of the support frame  138  within the furrow F. The location of the leading edge above the convergence location C allows the rod  150  to wear quickly so that the leading edge can quickly become sealed along the rotatable disc  178  (see  FIG. 4 ). 
         [0059]    Again, the fasteners  164  and holes  168  are configured to permit some off-axis pivoting of the fasteners  164  within the holes  168  and to allow some lateral movement of the fore plate  140 . The rod  150  is designed to wear from prolonged sliding engagement with the rotatable disc  78 . Thus, the rod  150  wears so that the leading edge serves as a sharp scraper edge. As the rod  150  wears, the joint  170  allows the support frame  138  to flex so that the rod  150  can remain in sliding contact with the rotatable disc  78 . 
         [0060]    The aft plate  142  is positioned so that a lower margin thereof extends into the furrow F and the trailing edge of the support frame  138  is positioned in the furrow F. The aft plate  142  runs along the furrow F adjacent the slot St to hold the seed shelf in place as the slot St is formed by the wedge  134  and to restrict soil from falling into the bottom part of furrow F. The aft plate  142  also runs adjacent the slot St so that the support frame  138  restricts seed S from dropping into the furrow F. Preferably, the trailing edge is positioned below a lowermost edge of wedge  134  a distance that ranges from about three-quarters (0.75) of an inch to about one and a quarter (1.25) inches. Furthermore, the trailing edge is preferably laterally spaced from the rotatable disc  78 . 
         [0061]    As mentioned above, the support frame  138  preferably supports the injectors  108 , 110 . The injectors  108 , 110  are preferably attached to the aft end of aft plate  142  with holder  176  (see  FIGS. 6 and 8 ). The toxic injector  108  is preferably positioned in front of non-toxic injector  110 . As discussed, the nozzles  120 , 122  inject the liquid APP/ATS mixture and the liquid anhydrous ammonia application to form the TAPPS band. Preferably, the TAPPS band is located at a fertilizer depth dimension FD that ranges from about three and three-quarters (3.75) inches to about five (5) inches (see  FIG. 14 ). Furthermore, depending on the location of the firming wedge  134  on the support frame  138 , the TAPPS band is preferably spaced alongside the seed S at a lateral spacing dimension that ranges from about three-quarters (0.75) of an inch to about one (1) inch and a vertical spacing dimension that ranges from about one and three-quarters (1.75) inches to about two and one-half (2.5) inches. 
         [0062]    Turning to  FIGS. 4-7  and  12 - 16 , the firming wedge  134  and seed catch pan  136  are removably secured to support frame  138  and serve to position seed along the shelf of slot St. Preferably, the wedge  134  comprises a solid unitary body that presents a lowermost edge  178  and an angled groove  180  that extends from an uppermost extent of the wedge  134  to the lowermost edge  178  (see  FIG. 16 ). The wedge  134  preferably has a wedge width dimension WW that ranges from about one-half (0.5) inch to about one (1) inch and, more preferably, is either about three-quarters (0.75) of an inch or about one (1) inch (see  FIG. 12 ). The wedge  134  preferably includes chrome or chrome carbide so that the wedge  134  resists wear, but the wedge  134  could include other materials. 
         [0063]    The wedge  134  is preferably removably secured to aft plate  142  by extending fasteners  182  through holes  184  in the wedge  134  and threading the fasteners  182  into corresponding threaded holes  186  in the aft plate  142  (see  FIG. 8 ). The holes  186  are located to provide three distinct wedge-mounting locations  187 . The wedge  134  is generally positioned within the shadow area SA, although a laterally outermost edge of firming wedge  134  is located outside of the shadow area SA a dimension that ranges from about zero (0) inches to about one-half (0.5) inch. 
         [0064]    As the wedge  134  is pulled through the field G by the support frame  138 , the wedge  134  forms the slot St within furrow F and thereby prepares the seed bed SB. In particular, the wedge  134  preferably bulges soil B along the side of furrow F in a lateral direction away from furrow F to form the slot St, including the shelf that receives seed S (see  FIG. 13 ). It has been found that the formation of slot St by bulging the soil laterally, rather than cutting into the soil, produces a mound of bulged soil B that tends to fall back into the slot St after the seed S has been pressed into the seed bed SB by the firming wheel. Preferably, the wedge  134  is positioned so that the lowermost edge  178  forms the bottom of slot St with a slot depth dimension of about two (2) inches, although the slot could have an alternative depth. 
         [0065]    The firming wedge  134  is preferably removably attached to the support frame  138  although, for some aspects of the present invention, the wedge  134  could be fixed to the support frame  138 . Also, the wedge  134  could be attached to another component of the opener  24 , e.g., where the wedge  134  is attached directly to catch pan  136 . 
         [0066]    Turning to  FIGS. 5 and 6 , the catch pan  136  distributes seed S received from the seed tank  32  via a seed tube  188 . The seed tube  188  is secured to the arm  52  by a bracket  190 . The illustrated seed tube  188  presents an outlet  188   a  that is positioned within the catch pan  136 . In the illustrated embodiment, the seed tube  188  is provided by cutting an original equipment seed tube to remove a lowermost section below the location of outlet  188   a . For instance, the lowermost four and one half (4½) inches of the seed tube from a Case SDX seeder are preferably removed to provide the illustrated opener. However, for some aspects of the present invention, the seed tube  188  could be provided with the illustrated length and configuration as part of an original equipment opener. 
         [0067]    Turning to  FIGS. 15 and 16 , the catch pan  136  preferably includes side walls  192 , 194 , and fore and aft walls  196 , 198 . The side walls  192 , 194  are preferably unitary and have a width dimension (measured along a fore-and-aft direction) that generally tapers from an upper funnel section  200  of the catch pan  136  to a rearwardly declining section  202  of the catch pan  136 . The fore wall  196  includes an upper continuous portion  204  and a lower vented portion  206 . The aft wall  198  also includes an upper continuous portion  208  and a lower vented portion  210 . The walls  192 , 194 , 196 , 198  preferably are made from 14-gauge A36 carbon steel, but could include other materials. 
         [0068]    The vented portions  206 , 210  preferably include a respective plurality of elongated slots  212   a,b  that present a slot width dimension Ws. The illustrated slots  212  include three rows of slots, with two slots arranged end-to-end in each row. However, the slots  212  could be alternatively positioned, e.g., to provide improved venting of the catch pan  136 . The slot width dimension Ws for slots  212  preferably ranges from about 0.030 inches to about 0.100 inches. The slot width dimension Ws for forward-facing slots  212   a  is preferably less than the slot width dimension Ws for rearward-facing slots  212   b  so that the fore wall  196  provides greater restriction than aft wall  198  to seed S becoming clogged in the corresponding slots  212   a  or foreign matter becoming clogged in slots  212   a  (e.g., due to soil impingement on pan  136  as the opener is moved forwardly). More preferably, the slot width dimension Ws for slots  212   a  ranges from about 0.09 inches to about 0.10 inches, and the slot width dimension Ws for slots  212   b  ranges from about 0.08 inches to about 0.09 inches in the illustrated embodiment. It has been found that clogging of slots  212 , particularly of forward-facing slots  212   a , with seed or foreign matter can harmfully restrict venting of the catch pan  136  so that the catch pan  136  becomes less effective at minimizing seed bounce. The above-noted dimensions have been found to be critical for minimizing clogging of slots  212 , particularly for larger seeds such as wheat. The material between adjacent slots  212  preferably has a width of about 0.077 inches. 
         [0069]    The walls  192 , 194 , 196 , 198  are interconnected to form an inlet  214  and outlet  216  connected by an elongated chamber  218 . The upper ends of side walls  192 , 194  include flaps  220  that are bent outwardly from the bottom of funnel section  200 . Thus, the width dimension of the funnel section  200 , as measured between the flaps  220 , tapers in the downward direction. In this manner, the inlet  214  is sized to receive the lower end of the seed tube  188 , and the funnel section  200  serves to collect seed S as the seed is deposited into the catch pan  136  from the seed tube  188 . 
         [0070]    The walls  192 , 194 , 196 , 198  along the rearwardly declining section  202  cooperatively define an axis A along the section that extends from the funnel section  200  downwardly and rearwardly (i.e., the axis A is at an oblique angle relative to the field G). The declining section  202  also is preferably configured to have a length dimension (i.e., as measured along the axis A) and a width dimension (as measured transversely to axis A) that tapers progressively from the funnel section  200  to the outlet  216 . These features of the declining section  202  have been found to minimize seed bounce when depositing seed S into the furrow F while permitting venting of pressurized air. 
         [0071]    The side walls  192 , 194  and the fore and aft walls  196 , 198  are preferably constructed so that the catch pan  136  presents a length dimension that ranges from about five (5) inches to about ten (10) inches and, more preferably, is about seven (7) inches. 
         [0072]    The outlet  216  is preferably defined by an open bottom  216   a  presented by the declining section  202  and a rearwardly-facing opening  216   b . The opening  216   b  is defined between the side walls  192 , 194  and extends upwardly from the open bottom  216   a  to the aft wall  198 , with the opening  216   b  extending along a lower margin of the declining section  202  (see  FIGS. 15 and 16 ). The opening  216   b  preferably presents a height dimension that is less than a width dimension thereof. In this manner, the aft wall  198  is positioned to restrict soil from entering the catch pan  136 . However, the outlet  216  could be alternatively configured to provide seed distribution without departing from the scope of the present invention. For example, in one alternative catch pan embodiment not depicted herein, the vented portion of aft wall could extend from the funnel section to a location about half way between the funnel section and the open bottom, with the opening extending along the backside of the pan downwardly between the sidewalls from the lower end of the vented portion to the open bottom. In the alternative embodiment, the catch pan could also include a shiftable vented wall portion pivotally attached to the lower end of the vented portion and extending from the vented portion to a location adjacent the open bottom. The shiftable wall portion could be pivotal relative to the vented portion into and out of a covering position where the shiftable wall portion substantially covers the opening. 
         [0073]    The outlet  216  preferably presents an outlet width dimension Wo that ranges from about one-quarter (0.25) inch to about three-quarters (0.75) of an inch and, more preferably, is about 0.58 inches in the illustrated embodiment (see  FIG. 16 ). The outlet  216  also preferably presents an outlet length dimension Lo that ranges from about one inch to about two inches and, more preferably, is about one and one-half inches in the illustrated embodiment (see  FIG. 15 ). The above-noted dimensions for the outlet  216  have been found to be particularly effective for distribution of larger seeds, such as wheat. 
         [0074]    Preferably, the number and arrangement of slots  212  along with the size of slots  212  permit adequate venting of the pressurized air that transmits seed S to the catch pan  136 . However, for some aspects of the present invention, the vents could be alternatively configured, e.g., where the side walls  192 , 194  include openings to vent air. The vent openings could also take different shapes for some aspects of the present invention. Furthermore, the catch pan  136  could have other alternative configurations, e.g., to minimize seed bounce as the seed is deposited into furrow F, or to otherwise provide precise distribution of seed. 
         [0075]    The side wall  192  includes a tab with holes  222 , 224  that allow the catch pan  136  to be attached to the aft plate  142  with fasteners. The hole  224  is elongated to permit rotation of the catch pan  136  about the axis of hole  222 . In this manner, the tab allows fine adjustment of the catch pan position. 
         [0076]    The lower end of catch pan  136  is preferably received in the groove  180  of the wedge  134  so that the fore wall  196  is positioned behind the wedge  134 . Furthermore, the outlet  216  of catch pan  136  is preferably spaced above the lowermost edge  178 . In this manner, the wedge  134  serves to protect the lower margin of catch pan  136  from contact with soil or other objects in field G as the opener is moved forwardly. The fore wall  196  is also positioned behind the wedge  134  so that the wedge serves to restrict clogging of slots  212   a  by foreign matter, e.g., matter that approaches the wedge  134  during forward movement of the opener. Furthermore, the fore wall  196  is preferably spaced rearwardly from a shoulder  226  of the wedge  134  so that the fore wall  196  and wedge  134  cooperatively define an air relief passage  228  (see  FIGS. 13 and 16 ). Thus, the passage  228  allows air to vent forwardly from the chamber  218  through the fore wall  196 . 
         [0077]    Preferably, the catch pan  136  is removably attached to the support frame  138 . In the illustrated embodiment, the firming wedge  134  and catch pan  136  are both preferably removable from the opener  24  so that the opener  24  can be used as a banding opener, e.g., for pre-plant banding. However, for some aspects of the present invention, the firming wedge  134  and catch pan  136  could be fixed to the opener  24 . Furthermore, it is within the ambit of the present invention where the entire support frame  138  is generally fixed relative to the arm  52  to support the firming wedge  134  and catch pan  136  in a fixed position relative to the arm  52  (e.g., where support frame  138  is not used as a disc-scraping mechanism). 
         [0078]    The illustrated catch pan  136  is preferably positioned with the nozzles  120 , 122  located laterally between the catch pan  136  and the disc  78 . Furthermore, the catch pan  136  and nozzles  120 , 122  are preferably located at least partly between laterally outermost edges of the disc  78  when the opener is viewed along a fore-and-aft direction. Thus, the catch pan  136  and nozzles  120 , 122  are at least partly positioned within a lateral disc profile. The catch pan  136  is also positioned so that the catch pan outlet is located behind the scraper edge formed by wear rod  150 . 
         [0079]    In operation, the tractor T pulls the air seeder  20  along the field G to distribute seed and fertilizer with minimal soil disturbance. With the openers  24  in the operating position, the gauge wheel  98  rolls along the field G, and the disc  78  cuts the furrow F. At the same time, the aft plate  142  and injectors  108 , 110  ride within the furrow F. Thus, the injectors  108 , 110  provide a dual-shot application of nitrogen, phosphorus, sulfur, and/or zinc in the furrow F as the opener  24  is pulled behind the toolbar. Furthermore, the firming wedge  134  forms the slot St with the outlet  216  of catch pan  136  behind the wedge  134 . Seed S is deposited into the slot St and comes to rest on the seed shelf so that the firming wheel can press the seed S into the seed bed SB. The soil displaced along slot St is generally moved by the firming wedge  134  so that the displaced soil falls back into the slot St after the seed S is deposited in the seed bed SB. Thus, the floating placement assembly  48  is operable to distribute seed S within the slot St and control the placement of the dedicated fertilizer band as the opener  24  is pulled behind the toolbar. 
         [0080]    Turning to  FIGS. 17 and 18 , an alternative vented seed catch pan  300  is constructed in accordance with a second embodiment of the present invention. For the sake of brevity, the remaining description will focus primarily on the differences of this alternative embodiment from the embodiment described above. 
         [0081]    The alternative catch pan  300  includes side walls  302 , 304 , and fore and aft walls  306 , 308 . The side walls  302 , 304  are preferably unitary and have a width dimension (measured along a fore-and-aft direction) that generally tapers from an upper funnel section  310  to a rearwardly declining section  312 . The fore wall  306  includes an upper continuous portion  314  and a lower vented portion  316 . The aft wall  308  also includes an upper continuous portion  318  and a lower vented portion  320 . 
         [0082]    The vented portions  316 , 320  preferably include a plurality of elongated slots  322   a,b  that present a slot width dimension Ws. The illustrated slots  322  on each section  316 , 320  include three slots that extend alongside one another, with the middle slot being longer than the slots on opposite ends. Preferably, the slot width dimension Ws for slots  322   a  is less than the slot width dimension Ws for slots  322   b . More preferably, the slot width dimension Ws for slots  322   a  ranges from about 0.030 inches to about 0.040 inches, and the slot width dimension Ws for slots  322   b  ranges from about 0.040 inches to about 0.050 inches in the illustrated embodiment. The above-noted dimensions have been found to be critical for minimizing clogging of slots  322 , particularly for smaller seeds such as mustard. 
         [0083]    The walls  302 , 304 , 306 , 308  are interconnected to form an inlet  324  and outlet  326  connected by an elongated chamber  328 . The upper ends of side walls  302 , 304  include flaps  330  that are bent outwardly from the bottom of funnel section  310 . Thus, the width dimension of the funnel section  310 , as measured between the flaps  330 , tapers in the downward direction. In this manner, the inlet  324  is sized to receive the lower end of the seed tube, and the funnel section  310  serves to collect seed S as the seed is deposited into the catch pan  300  from the seed tube. 
         [0084]    The outlet  326  preferably presents an outlet width dimension that is about 0.265 inches in the illustrated embodiment. The outlet  326  also preferably presents an outlet length dimension that ranges from about one (1) inch to about two (2) inches and, more preferably, is about one and one-half (1½) inches in the illustrated embodiment. The alternative catch pan  300  generally operates in the same manner as the previously described catch pan embodiments. 
         [0085]    The preferred forms of the invention described above are to be used as illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention. 
         [0086]    The inventor hereby states his intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of the present invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set forth in the following claims.