Abstract:
A twin row planter ( 10 ) includes planting units ( 20   a-   26   b ) arranged in pairs ( 20-26 ). Each pair ( 20-26 ) is configured and positioned for planting two rows ( 78,80 ) of seeds less than about ten inches apart to produce two rows of crops in order to increase the yield of the plot. With this spacing, the rows ( 78,80 ) in each pair are close enough to simulate a single row enabling the use of a conventional cultivator, sprayer or harvesting machine.

Description:
RELATED APPLICATIONS 
     This is a continuation of application Ser. No. 09/159,731 filed Sep. 24, 1998, which is hereby incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of agricultural planters. More particularly, the invention is concerned with a twin row planter including planting units arranged in pairs. Each pair is configured and positioned for planting two rows of seeds less than about ten inches apart to produce two rows of crops in order to increase the yield of the plot. With this spacing, the rows in each pair are close enough to simulate a single row enabling the use of a conventional cultivator, sprayer or harvesting machine. 
     2. Description of the Prior Art 
     Conventional planters include a plurality of evenly spaced planting units connected to a tool bar. The planters are usually on centers of 30, 36 38 or 40 inches which is the spacing required for conventional harvesting machines. It is known that rows planted more closely together can result in a higher yield for a given plot of land, but conventional cultivators, sprayers and harvesting machines cannot handle these closely spaced rows. As a result, crop yield is lost and land use is less efficient. 
     SUMMARY OF THE INVENTION 
     The present invention solves the prior art problems mentioned above and provides a distinct advance in the state of the art. More particularly, the planter hereof enables the planting of more closely spaced rows in order to increase crop yield in a manner allowing harvesting by conventional harvesting machines. 
     The preferred planter includes a plurality of planting units mounted to a tool bar with the planting units arranged in pairs. The pairs of planting units are arranged on standard centers such as thirty or thirty-six inches, for example, but the planting units of each pair are positioned and configured so that the respective rows planted by each pair of planting units are spaced apart less than about ten inches. With this spacing, each set of two rows of resulting crops are close enough to simulate a single row thereby enabling the use of a conventional harvesting machine. Other preferred aspects of the present invention are disclosed herein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of the preferred planter in accordance with the present invention; 
     FIG. 2 is a plan view of a pair of planting units of FIG. 1 shown mounted to the tool bar; 
     FIG. 3 is a side elevational view in partial section taken along line  3 — 3  of FIG. 2; 
     FIG. 4 is a side elevational view in partial section taken along line  4 — 4  of FIG. 2; and 
     FIG. 5 is a plan view in partial section taken along line  5 — 5  of FIG.  3 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The drawing figures illustrate preferred planter  10  in accordance with the present invention. Referring to FIG. 1, planter  10  includes tool bar  12 , drive wheels  14  and  16  coupled with and supporting tool bar  12 , drive mechanism  18  and a plurality of planting units  20   a,    20   b,    22   a,    22   b,    24   a,    24   b,    26   a  and  26   b  arranged in pairs  20 ,  22 ,  24 ,  26 . Tool bar  12 , drive wheels  14 , 16  and drive mechanism  18  are conventional components such as those available on the MONOSEM planter available from ATI, Inc. of Lenexa, Kans. Pairs  20 - 26  are substantially identical except for their relative positions along tool bar  12 . 
     Referring to pair  20 , planting unit  20   a  includes a furrow opener including a pair of opener discs  28  seed hopper  30 , metering assembly  32 , a depth gauge wheel assembly including inboard depth gauge wheel  34  and outboard depth gauge wheel  36 , and a furrow closer including closer wheels  38 . In the usual manner, the planting unit  20   a  further includes a seed tube  39  that extends downwardly from the metering assembly  32  and between the discs  28  so that the lower outlet end  40  is received in the furrow (see FIGS.  3  and  5 ). In this regard, the seed tube  39  serves to deposit seed metered by the assembly  32  into the furrow. As best viewed in FIG. 5, inboard depth gauge wheel  34  is narrower than outboard wheel  36  by about half the width thereof. Except for this difference, planting unit  20   a  is otherwise conventional such as the MONOSEM planting unit available from ATI, Inc. 
     Mounting structure  42  includes spacer  44  having extender  46  and cross bar  48 . U-bolts  50  couple extender  46  with tool bar  12  and U-bolts  52  couple mounting face  54  of planter  20   a  with cross bar  48 . Spacer  44  is configured to space planting unit  20   a  about six inches from tool bar  12 . This places planting unit  20   a  in a staggered relationship relative to planting unit  20   b  with portions thereof overlapping as best viewed in FIGS. 1,  2  and  5 . 
     Referring to FIG. 3, drive mechanism  18  includes conventional drive shaft  56 . Mounting structure  42  includes power transfer assembly  58  for transferring mechanical power from drive shaft  56  to planting unit  20   a  to operate metering assembly  32 , needed because of the spacing from tool bar  12 . Power transfer assembly  58  includes drive sprocket  60  coupled with drive shaft  56 , driven sprocket  62  coupled with power shaft  63  of planting unit  20   a,  chain  64  intercoupling sprockets  60 ,  62  and idler sprocket  66  engaged with chain  64  to maintain the tension thereof. 
     Planting unit  20   b  includes mounting face  68  mounted to tool bar  12  with no spacer therebetween. Unit  20   b  is otherwise the same as planting unit  20   a  except for the orientation of seed hopper  72 . Referring to FIG. 2, seed hopper  72  is turned on its mounting (compared to hopper  30  of unit  20   a ) so that it extends substantially to one side of the centerline of planting unit  20   b.  Planting unit  20   b  also includes a narrow inboard depth gauge wheel  74  and outboard depth gauge wheel  76 . 
     Referring to FIGS. 1,  2  and  5 , planting units  20   a,b  are positioned on centers of about nine inches in the preferred embodiment. With this arrangement, units  20   a,b  plant twin rows of seeds  78  and  80  also spaced apart about nine inches as are the resulting rows of crops. This is critical because conventional harvesters cannot adequately handle a crop row with a width greater than ten inches. With a spacing of less than about ten inches, the crops from rows  78 , 80  simulate a single row to a conventional harvesting machine. The planting units in the other pairs  22 - 26  are also on nine inch centers, but the pairs themselves are spaced as needed for the harvesting machine that will be used to harvest the crop. In the preferred embodiment, pairs  20 - 26  are spaced at 30 inches but spacings of  36 ,  38  and  40  inches are also common. 
     As best viewed in FIG. 2, the orientation of seed hopper  72  to the right of the centerline of planting unit  20   b  enables the close spacing between units  20   a  and  20   b.  This close spacing is further enabled by the narrow width of inboard depth gauge wheels  34  and  74  as shown in FIG.  5  and by the staggered relationship between units  20   a  and  20   b.  As further illustrated by FIG. 5, and the other drawing figures, planting units  20   a,b  also overlap. In this relationship, the forward portion of inboard depth gauge wheel  34  is adjacent the rearward portion of inboard depth gauge wheel  74 . In this relationship, wheels  34  and  74  move in opposite directions where they overlap as planter  10  moves along the ground. This prevents dirt clods, rocks and crop residue from lodging between wheels  34  and  74 , which might otherwise be a problem if units  20   a,b  were not staggered. 
     In the use of planter  10 , metering assemblies  32  of each planting unit  20   a - 26   b  are adjusted as needed for the desired seed spacing. Also, the metering assemblies and mounting structures are adjusted, as needed, so that the seeds planted in each row pair are also staggered as illustrated in FIG.  5 . This maximizes the spacing between the seeds in the twin rows for maximum yield. 
     For a conventional planter, the normal seed spacing might be 8 seeds per foot. With the present invention, the metering assemblies can be adjusted so that each places about 6 seeds per foot, for example. For the double row planted by each pair of planting units, this results in 12 seeds per foot, which is a 50% increase in the amount of seed planted. It has been found that this can result in a yield increase of about 25% which substantially offsets the additional cost of seed and increases the overall profit on a given plot. 
     As those skilled in the art will appreciate, the present invention encompasses many variations in the preferred embodiment described herein. Having described this embodiment, the following is claimed as new and desired to be secured by Letters Patent: