Abstract:
A seed firmer for firming seeds deposited in the seed trench to ensure good seed-to-soil contact. A bracket mounts the seed firmer to the row unit frame such that the seed firmer is aligned with the seed trench. The seed firmer includes a resilient insert positioned in the firmer body to stiffen the seed firmer to more resiliently firm the seed into the soil.

Description:
BACKGROUND 
       [0001]    In recent years, farmers have recognized the need to enhance seed-to-soil contact in order to create the proper environment for seed germination and emergence after planting. Seed firmers have thus been developed for pressing the seed into the soil subsequent to placement in the seed trench. However, existing firmers have varying effectiveness in certain soil conditions and soil types. Additionally, the increased pressure to perform planting operations at high speeds have in some cases limited the effectiveness of existing firmer designs. Thus, there is a need for a seed firmer for an agricultural planter row unit providing for more effective firming of the seed resulting in improved seed-to-soil contact. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0002]      FIG. 1  is a right side elevation view of a row unit of an agricultural planter with an embodiment of a seed firmer mounted to a shank of the row unit. 
           [0003]      FIG. 2  is an enlarged view of  FIG. 1  with the right opening disc and gauge wheel removed for clarity to show the seed firmer mounted to the shank of the row unit. 
           [0004]      FIG. 3  is a rear perspective view of an embodiment of the seed firmer. 
           [0005]      FIG. 4  is a right side elevation view of the seed firmer of  FIG. 3 . 
           [0006]      FIG. 5  is a front elevation view of the seed firmer of  FIG. 3 . 
           [0007]      FIG. 6  is a cross-sectional view of the seed firmer as viewed along line  6 - 6  of  FIG. 4 . 
           [0008]      FIG. 7  is an enlarged view of  FIG. 2  showing an embodiment of the seed firmer and mounting bracket for mounting the seed firmer to the shank of the row unit frame. 
           [0009]      FIG. 8  shows the firmer flexing about the central portion of the firmer body. 
           [0010]      FIG. 9  is a cross-sectional view of another embodiment of a seed firmer. 
           [0011]      FIG. 10  is a cross-sectional view of yet another embodiment of a seed firmer. 
           [0012]      FIG. 11  is an enlarged cross-sectional view of the firmer within the seed trench as viewed along lines  11 - 11  of  FIG. 2 . 
           [0013]      FIG. 12  is the same view as  FIG. 11  illustrating an alternative embodiment of the lower surface of the seed firmer. 
       
    
    
     DESCRIPTION 
       [0014]    Referring to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views,  FIG. 1  is a side elevation view of a row unit  10  of a conventional agricultural planter with a seed firmer  100  mounted to the row unit  10 . It should be understood that the planter comprises a plurality of row units  10  mounted along the toolbar  8  in spaced relation. The row units  10  are mounted to the toolbar  8  by a parallel arm linkage  16  permitting the individual row units  10  to independently translate vertically with respect to the toolbar  8 . The row unit  10  is shown as incorporating an actuator  18  mounted to the toolbar  8  and the parallel arm linkage  16  to apply supplemental downpressure to the row unit  10 . 
         [0015]    The row unit  10  includes a frame  14  having a downwardly extending shank  15 . The frame  14  supports an opening disc assembly  60 , a gauge wheel assembly  50  and a closing assembly  40 . The opening assembly  60  includes two opening discs  62  rotatable about a shaft  63  supported by the shank  15 . The opening discs  62  are disposed to cut a v-shaped trench  3  in the soil surface  7  as the row unit is drawn through the field in the direction of arrow  11 . The gauge wheel assembly  50  includes two gauge wheels  52  pivotally mounted to the frame  14  by gauge wheel arms  54 . A depth adjustment assembly  90  adjustably positions the gauge wheels  52  with respect to the opening discs  62  by contacting the gauge wheel arms  54  to limit the upward travel of the gauge wheel arms  54 , thus limiting the depth of the trench  3  opened by the opening discs  62 . The closing assembly  40  may include closing wheels  42  disposed to move soil back into the trench  3  to cover the seeds previously deposited as discussed below. 
         [0016]    Continuing to refer to  FIG. 1 , seeds  5  are communicated from a hopper  12  to a seed meter  30  which dispenses seeds into the seed tube  32  extending downwardly and rearwardly toward the seed trench  3  between the opening discs  62  and the gauge wheels  52 . The seed meter  30  may be any type of well known and commercially available seed meter, including for example, a vacuum-type meter such as disclosed in Applicant&#39;s co-pending international patent application no. PCT/US2012/030192 (Pub. No. WO/2012/129442), the disclosure of which is hereby incorporated by reference herein in its entirety. 
         [0017]    In operation, as the planter is drawn through the field in the direction of arrow  11 , the seeds  5  dispensed by the meter  30  are directed downwardly and rearwardly by the seed tube  32  where they are deposited in the seed trench  3  formed by the opening discs  62 . A seed firmer  100  (discussed in detail below) presses the deposited seeds  5  into the soil at the bottom of the seed trench  3  before the seeds are covered with soil by the closing assembly  40 . 
         [0018]      FIG. 2  is an enlarged view of  FIG. 1  with the right side gauge wheel  52  and right side opening disc  62  showing an embodiment of the seed firmer  100  and the bracket  200  mounted to the shank  15  of the row unit  10 . 
       Seed Firmer 
       [0019]      FIG. 3  is a rear perspective view of one embodiment of the seed firmer  100 .  FIG. 4  is a right side elevation view of the seed firmer  100  of  FIG. 3  and  FIG. 5  is a front elevation view of the seed firmer  100  of  FIG. 3 . The seed firmer  100  comprises a body  102  having a longitudinal centerline  101 . The firmer body  102  is preferably comprised of plastic or other suitably resilient material which is durable to minimize rapid wear. 
         [0020]    The firmer body  102  includes an upper portion  110 , a central portion  120 , and a lower portion  130 . The upper portion  110  preferably includes a lower bracket arm  162  and an upper bracket arm  164  for mounting the firmer body  102  to the mounting bracket  200  (discussed later). When mounted within the mounting bracket  200  the upper portion  110  is substantially restrained from bending or flexing. The lower portion  130  of the firmer body  102  has a larger section modulus than the upper and central portions  110 ,  120  of the firmer body  102  such that the lower portion  130  is relatively inflexible in relation to the central portion  120  of the firmer body  102 . Thus, when the row unit  10  is lowered toward the soil such that the lower surface  132  of the lower portion  130  of the firmer body  102  engages the soil, the firmer  100  will tend to flex or deform elastically at the central portion  120  as best illustrated in  FIG. 8 . As the central portion  120  flexes or elastically deforms, the central portion  120  imposes a moment on the lower portion  130  causing the lower surface  132  of the resilient firmer body  102  to be biased downwardly toward the soil such that as the lower surface  132  passes over the deposited seeds  5  in the bottom of the trench  3 , the deposited seeds are firmly pressed into the soil ensuring good seed-to-soil contact. 
         [0021]    In a preferred embodiment, the upper portion  110  has a thickness T u  ( FIG. 4 ) of preferably approximately 0.25 inches. A thickness T b  ( FIG. 3 ) of a transition area between the central portion  120  and the lower portion  130  is preferably approximately 0.9 inches. 
         [0022]    To add stiffness to the seed firmer  100 , the seed firmer body  102  preferably includes an insert  150  made of a resilient material having a greater stiffness than the material used for the seed firmer body  102 . In a preferred embodiment, the insert  150  is made of spring steel. The insert  150  has a thickness T ( FIG. 4 ) and may comprise a single member or multiple layers (discussed later). The insert  150  is preferably oriented within the firmer body  102  as illustrated in  FIGS. 4 and 5  and extends through the central portion  120  and into the upper portion  110  and lower portion  130  of the seed firmer body  102 . It should be appreciated that the stiffness of the firmer  100  is therefore directly related to the thickness of the insert  150 . The thickness T may be between about 0.01 and about 0.07 inches and preferably about 0.04 inches. 
         [0023]    In embodiments where the insert  150  is made of multiple layers, a thickness T of the insert  150  is preferably approximately between 0.08 and 0.1 inches and preferably about 0.09 inches, with the insert  150  preferably comprising three substantially identical insert pieces stacked along the direction of thickness T with each insert piece having a thickness of approximately 0.03 inches. By using multiple layers, the insert pieces are able to slide relative to one another as the firmer  100  flexes during use. 
         [0024]    The firmer body  102  is preferably overmolded around the insert  150  using an injection molding process. During injection molding of the firmer body  102 , pins (not shown) preferably retain the insert  150  vertically and horizontally within the mold resulting in upper and lower arrays of pin holes  172  in the resulting seed firmer body  102 . Also during injection molding of the seed firmer body  102 , pins (not shown) preferably engage the insert  150  from the front side and rear side of the insert to prevent movement and bending of the insert  150  during molding resulting in pin holes  174  ( FIGS. 3 and 5 ) in the front and rear sides of the firmer body  102 . 
         [0025]    The seed firmer  100  is preferably adapted to support a liquid conduit  80  ( FIG. 4 ) for depositing liquid near a trailing end of the seed firmer  100 . The upper and lower bracket arms  162 ,  164  may include apertures  161  through which the conduit  80  may extend. The conduit  80  may be supported along the firmer body  102  by hooks  144  and  142 . The top surface  134  of the lower portion  130  of the firmer body  102  preferably includes a channel  140  ( FIGS. 3 and 6 ) sized to receive the liquid conduit  80 . The end of the liquid conduit  80  may include a nozzle  82  retained in position by a notch  184  in the lower portion  130 . 
         [0026]    Referring to  FIG. 9 , another embodiment of a seed firmer  100 A is illustrated in cross-section. As in the previous embodiment, the seed firmer  100 A comprises a firmer body having an upper portion  110 , a central portion  120  and a lower portion  130 . An insert  150  is overmolded or otherwise provided within the seed firmer body  102  and, as in the previous embodiment, the insert  150  has a greater effective stiffness than the material comprising the firmer body  102 . Also as with the previous embodiment, the insert  150  extends through the central portion and into the upper and lower portions  110 ,  130  of the firmer body  102 . Also as in the previous embodiment, a liquid conduit  80  is preferably secured in place by the hooks  142 ,  144  and by apertures  161  through the bracket arms  162 ,  164 . However, in the embodiment of  FIG. 9 , the liquid conduit  80  is preferably releasably retained over the top surface of the lower portion  130  by a cover  180  which may be releasably secured over the channel  140  formed in the top surface of the lower portion  130  of the firmer body as in the previous embodiment or the cover  180  may be an attachment removably or fixedly secured along the top surface of the lower portion  130 . As in the previous embodiment, a nozzle  82  at the end of the liquid conduit  80  may be retained in position by a notch  184  in the lower portion  130 . 
         [0027]    Referring to  FIG. 10 , another embodiment of a seed firmer  100 B is illustrated in cross-section. In this embodiment, the seed firmer  100 B is generally similar to either of the previous embodiments  100 ,  100 A except that instead of an open channel  140  or a cover  180 , the seed firmer includes an elongated cavity  190  formed along the top surface of the lower portion  130 . The elongated cavity  190  preferably includes an inlet end  192  at a forward end of the lower portion  130  and an outlet end  194  at a rearward end of the lower portion  130 . The elongated cavity  190  may comprise an overmolded steel tube or the cavity may simply be a void formed along the top surface of the lower portion  130 . The conduit  80  may extend through the cavity  190  or the conduit  80  may terminate at the inlet end  192  such that the liquid flows directly through the cavity  190 . The cavity  190  preferably includes a bend  196  for directing the flow of liquid, or the terminal end of the liquid conduit  80  (with or without a nozzle) downwardly at the rearward end of the firmer  100 B. 
         [0028]      FIG. 11  is a cross sectional view of the seed firmer  100 ,  100 A,  100 B positioned within the seed trench as viewed along lines  11 - 11  of  FIG. 2 . The lower surface  132  preferably has a substantially flat portion having a width Wb greater than the width of the deposited seeds  5  in the trench but the width Wb preferably substantially equal to or less than the width of the bottom of the trench  3 . In  FIG. 12 , an alternative embodiment of a lower surface  132  of the firmer body  102  is shown in which the lower surface  132  includes a concave recess  133  such that the seed  5  is partially received within the recess  133  when the lower surface  132  engages the bottom of the trench. 
       Seed Firmer Mounting Bracket 
       [0029]    Referring to  FIG. 7 , the mounting bracket  200  is illustrated in more detail supporting the seed firmer  100 ,  100 A,  100 B. The bracket preferably includes left and right sidewalls  210  transversely spaced to accommodate the seed tube  32 . The bracket  200  is preferably mounted to each side of the shank  15  by a bolt or shaft extending through forwardly projecting mounting ears  262 . The bracket  200  may also include a forwardly projecting upper hook  264  for hooking over an existing shaft or pin on the shank  15  or alternatively a second pair of forwardly extending ears (not shown) may be provided instead of an upper hook depending on the make and model of the planter to which the bracket  200  is to be mounted. 
         [0030]    The rearward end of the bracket  200  preferably includes a forward surface  220  and a back surface  230 . The forward surface  220  supports a forward side of the upper portion  110  of the firmer body  102 . The back surface  230  is received between the upper and lower bracket arms  162 ,  164 . The lower bracket arm  162  includes a seat  163  (see also  FIG. 4 ) which receives a bottom edge of the back surface  230 . The upper bracket arm  164  includes a lip  165  (see also  FIG. 4 ) which engages the top edge of the back surface  230 . 
         [0031]    To attach the firmer  100  to the bracket  200 , the resilient upper bracket arm  164  is bent upwardly permitting the upper portion  110  of the firmer body  102  and the upper bracket arm  164  to pass upwardly between the forward surface  220  and back surface  230  of the bracket  200  until the seat  163  of the lower bracket arm  162  engages the bottom edge of the back surface  230 . With the forward side of the upper portion  110  engaging the forward surface  220  of the bracket  200 , and with the bottom edge of the back surface  230  seated on the seat  163 , the bending force exerted on the upper bracket arm  164  is released. The resiliency of the upper bracket arm  164  biases the upper bracket arm downwardly clamping the back surface  230  between the lip  165  and the seat  163 . It should be appreciated that the upper portion  110  is thereby substantially restrained such that the upper portion  110  is substantially inflexible. To remove the seed firmer  100  from the bracket  200 , the upper bracket arm  164  is bent upwardly (to the right on the view of  FIG. 7 ) until the upper portion  110  can be lowered and released from the bracket  200 . 
         [0032]    The foregoing description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the preferred embodiment of the apparatus, and the general principles and features of the system and methods described herein will be readily apparent to those of skill in the art. Thus, the present invention is not to be limited to the embodiments of the apparatus, system and methods described above and illustrated in the drawing figures, but is to be accorded the widest scope consistent with the spirit and scope of the appended claims.