Abstract:
An agricultural planting apparatus including a chassis; and a row unit carried by the chassis. The row unit includes a unit body carried by the chassis; a metering device carried by the unit body; at least one furrowing disc carried by the unit body; a biasing element carried by the unit body that is selected from the group consisting of an extension spring, a compression spring, and a cylinder; and a pair of pinch wheels carried by the unit body behind the at least one furrowing disc and including an axle assembly pivotally movable relative to said unit body and connected to said biasing element. The axle assembly is configured to readily connect to any of the group members of the biasing element.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to agricultural planters, and, more particularly, to agricultural planter row units. 
         [0003]    2. Description of the Related Art 
         [0004]    Agricultural planters are commonly used implements to plant seeds in soil. An agricultural planter can include a chassis that carries one or more storage tanks carrying seed, and chemical applications that are to be applied to the field during the planting operation, a hitch mechanism that attaches to a tractor or other implement pulled by a tractor, and a tool bar that row units can be connected to so they are carried by the chassis. The planter can also include a pneumatic system carried by the chassis that supplies pressurized air to transport the seeds or other particulate from the storage tanks to the row units. 
         [0005]    Each row unit of the agricultural planter places seeds in the field. Typically, the row units are laterally arranged along a length of the tool bar so that as the planter is pulled across the field, each row unit plants seeds at predefined intervals along the path it is pulled across. To plant seeds, the row units perform three main operations as they are pulled: opening a trench in the soil; placing a seed into the formed trench at appropriate intervals; and closing the formed trench to put soil on top of the placed seed. To open a trench in the soil, a furrowing disc system, which may include an opening disc, cuts into the soil and rotates, dislocating soil as it rotates to form the trench. Once the trench is open, a seed is placed in the trench by a metering device which receives seeds from the main storage tank(s) or a row unit storage tank and typically utilizes a combination of differential air pressure, to select the seed, and gravity to place the seed in the trench at predefined intervals along the pulled path so that adjacent seeds in the row are not too close to one another. Pinch wheels carried behind the furrowing disc are pressed into the soil and also rotate as the planter is pulled to replace soil dislocated by the furrowing disc in the trench or dislocate adjacent soil into the trench to cover the seed placed in the trench with soil, as well as pack the soil onto the seed to provide good soil contact. By having multiple row units working in unison as the planter is pulled across a field, many seeds can be effectively planted in an efficient manner. 
         [0006]    As the row unit is pulled across the field, a down force is typically applied to the pinch wheels to force the pinch wheels into the soil so that the pinch wheels maintain constant soil contact. The down force can be provided by, for example, a pneumatic cylinder or various types of springs. As farmers try to plant at different times in the season, conditions for closing the formed trench can change. When planting early in the season, for example, difficult soil conditions can require additional down force be applied to the pinch wheel(s) compared to conditions later in the season. A pneumatic cylinder allows the farmer to apply the required down force for early planting, but is typically more expensive and complicated compared to other elements that can provide down force to the pinch wheel(s), such as an extension or compression spring. Further, pneumatic cylinders require more components than springs, such as relatively heavy air compressors, which can add to the weight of the row unit and provide more possible failure points. 
         [0007]    What is needed in the art is a way to apply downforce to the pinch wheels while overcoming some of the aforementioned disadvantages. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention provides an agricultural planter with a row unit having pinch wheels which include an axle assembly that can connect to a variety of biasing elements to provide downforce to the pinch wheels. 
         [0009]    The invention in one form is directed to an agricultural planting apparatus including a chassis; and a row unit carried by the chassis. The row unit includes a unit body carried by the chassis; a metering device carried by the unit body; at least one furrowing disc carried by the unit body; a biasing element carried by the unit body that is selected from the group consisting of an extension spring, a compression spring, and a cylinder; and a pair of pinch wheels carried by the unit body behind the at least one furrowing disc and including an axle assembly pivotally movable relative to said unit body and connected to said biasing element. The axle assembly is configured to readily connect to any of the group members of the biasing element. 
         [0010]    The invention in another form is directed to a closing assembly for an agricultural planting apparatus that includes a mounting body; a biasing element connected to the mounting body that is selected from the group consisting of an extension spring, a compression spring, and a cylinder; and a pair of pinch wheels including an axle assembly pivotally connected to the mounting body and connected to the biasing element. The axle assembly is configured to readily connect to any of the group members of the biasing element. 
         [0011]    An advantage of the present invention is that different biasing elements can be connected to the axle assembly to apply down force to the pinch wheels. 
         [0012]    Another advantage is that relatively few components need to be switched out to change the type of biasing element connected to the axle assembly, simplifying the changing procedure and reducing cost. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0014]      FIG. 1  is a perspective view of an embodiment of an agricultural planter according to the present invention; 
           [0015]      FIG. 2  is a perspective view of an embodiment of a row unit according to the present invention; 
           [0016]      FIG. 3  is a perspective view of a closing assembly shown in  FIG. 2  disconnected from the row unit; 
           [0017]      FIG. 4  is a perspective view of the closing assembly shown in  FIGS. 2-3  with a biasing element shown only as a cylinder; 
           [0018]      FIG. 5  is a perspective view of the closing assembly shown in  FIGS. 2-4  with a compression spring shown as the biasing element; and 
           [0019]      FIG. 6  is a perspective view of the closing assembly shown in  FIGS. 2-5  with an extension spring shown as the biasing element. 
       
    
    
       [0020]    Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one embodiment of the invention and such exemplification is not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    Referring now to the drawings, and more particularly to  FIG. 1 , there is shown an embodiment of an agricultural planter  10  according to the present invention which generally includes a chassis  11  forming a support structure for components of the planter  10 . The planter  10  can include a hitch assembly  12  at a front of the planter  10  connected to a tool bar  14  to form the chassis  11 , main wheels  16  carried by the chassis  11  near a rear of the planter  10 , one or more storage tanks  18 ,  20 ,  22  carried by the chassis  11  that can be filled with seed or other agriculture material, and a plurality of row units  24  connected to the tool bar  14  and arranged laterally across a length of the tool bar  14  so that they are carried by the chassis. The hitch assembly  12  can include a hitch  26  configured to be connected to a tractor or other agricultural implement (not shown) so that the planter  10  can be pulled in a forward direction of travel. The hitch  26  can be integrally formed with or connected to a hitch bar  28  that is connected to the tool bar  14  by bracing bars  30  and one or more cylinders  32 . As can be seen throughout  FIG. 1 , the planter  10  can also have various hydraulic, pneumatic, and electrical lines (unnumbered) throughout to support various cylinders and systems that are included on the planter  10 , such as a pneumatic system  34  connected to the tool bar  16  and an electric generator  36  also connected to the tool bar  16 . A marking device  38  can be connected to each lateral end of the tool bar  14  and extendable so that a marking disc  40  of the marking device  38  can create a line in the soil as the planter  10  is pulled that helps a user in positioning the planter  10  to create subsequent rows. A stair assembly  42  can be mounted to the back of the planter  10  to allow an operator to access the storage tanks  20  and  22 . 
         [0022]    Referring now to  FIG. 2 , an embodiment of an individual row unit  24  is shown that is not connected to the tool bar  14 . As can be seen, the row unit  24  generally includes a unit body  44  that can be carried by the chassis  11  in a direction of travel, signified by arrow  46 , a metering device  48  carried by the unit body  44 , a furrowing disc  50  connected to the unit body  44 , and a closing assembly  54  carried by the unit body  44  that can include a mounting body  52  connected to the unit body  44 , a biasing element  56  connected to the mounting body  52 , and a pair of pinch wheels  58  carried behind the furrowing disc  50  by connection to the mounting body  52 . As can be seen, the unit body  44  can have toolbar connecting arms  60  bolted thereon that can be connected to the chassis  11  in a parallel linkage arrangement so that the row unit  24  can be carried by the chassis  11  in the direction of travel  46 . In this sense, the unit body  44  acts as a row unit chassis to keep the various components of the row unit  24  together during operation. 
         [0023]    The metering device  48  carried by the unit body  44  is configured to receive seed from a unit storage tank  62  (also known as a mini-hopper) that is carried by the unit body  44  and can connect to one or more of the main storage tanks  18 ,  20  or  22 . For ease of illustration, the electrical and pneumatic lines that would normally be connected to the metering device  48  have been omitted. The metering device  48  can be configured as any type of device which is capable of controllably metering out seeds to be planted by the row unit  24  during operation of the planter  10 . For example, the metering device  48  can utilize a metering wheel (not shown) in combination with a vacuum formed in the metering device  48  to selectively pull seeds into a seed drop (not shown), where the vacuum is released and gravity causes the seed to drop into soil below. Other types of metering devices are known and could readily be adopted into the row unit  24  of the present invention. 
         [0024]    The furrowing disc  50  carried by the unit body  44  presses into the soil and rotates as the planter  10  travels along a field, displacing soil in the field to form a trench. The furrowing disc  50  can have any type of construction that allows for it to rotate as it is carried along the field to form a trench in the soil, such as the annular disc shape shown. While only one furrowing disc  50  is shown, it is contemplated that two furrowing discs can be included in the row unit  24 . Many different types of furrowing disc constructions are known and could be included in the row unit  24 . Optionally, the furrowing disc(s)  50  can be connected to the unit body  44  by a furrowing suspension assembly  64  including one or more adjustable gauge wheels  65  that are configured to adjust the depth of the trenches formed by the furrowing disc(s)  50  as the planter  10  travels along the field. Any suitable furrowing suspension assembly can be used to connect the furrowing disc(s)  50  to the unit body  44 . 
         [0025]    Referring specifically now to  FIG. 3 , the closing assembly  54  is shown separately from the rest of the row unit  24 . It should therefore be appreciated that the closing assembly  54  can be included as a part of the row unit  24  initially, or retrofitted to the row unit  24 . 
         [0026]    The mounting body  52  can be bolted to the unit body  44 , as shown in  FIG. 2 , so that it can carry the connected biasing element  56  and pinch wheels  58  with the unit body  44  as the planter  10  travels across the field. The mounting body  52  can be a pair of connected plates  66  with a space formed between the plates  66 , as shown, or any other suitable construction. The profile and mounting angle of the mounting body  52  can be adjusted to cover adjacent assemblies or parts, as desired. 
         [0027]    The biasing element  56 , shown as a solid line pneumatic cylinder in  FIGS. 2-4 , is carried by the unit body  44  and connects to an axle assembly (not shown in  FIG. 3 ) of the pinch wheels  58 , which will be described further herein, to bias the pinch wheels  58  toward the ground as the row unit  24  is carried across the field. The biasing element  56  can be connected to the mounting body  52 , as shown, or otherwise associated with the unit body  44  so that the biasing element  56  is carried by the unit body  44  during operation of the planter  10 . The biasing element  56  can also be directly connected to the unit body  44 , if desired. While the biasing element  56  is shown in  FIG. 3  as a pneumatic cylinder, a hydraulic cylinder can also be used as the biasing element  56 . In  FIG. 3 , three different possible biasing elements that can be part of the closing assembly  54  are shown: a pneumatic cylinder  56  drawn in solid lines, a compression spring  68  drawn in broken lines, and an extension spring  70  drawn in broken lines. The compression spring  68  and extension spring  70  are illustrated in  FIG. 3 , as well as pneumatic cylinder  56 , to demonstrate how the springs  68  and  70  can be connected to the pinch wheels  58  and mounting body  52 , but in use only one of the biasing elements  56 ,  68  and  70  is likely to be connected to the pinch wheels  58  at a time, although it is contemplated that two or all three of the biasing elements  56 ,  68  and  70  can be connected to the pinch wheels  58  at the same time. As shown in  FIG. 3 , the pneumatic cylinder  56  can be connected to the mounting body  52  by one or more pins  57  extending through one or more openings (not seen) formed at an end  59  of the pneumatic cylinder  56  and one or more openings  61  formed in the mounting body  52  defining a mounting feature. It should be appreciated that any type of mounting feature can be included on the mounting body  52  to connect the pneumatic cylinder  56  to the mounting body  52 . 
         [0028]    As shown, the pinch wheels  58  are configured as a pair of wheels  58  that are angled relative to one another so that the pinch wheels  58  converge toward a pinching area. As the row unit  24  is carried across the field, the pinch wheels  58  are carried behind the furrowing disc  50  in the direction of travel  46  and “pinch” soil adjacent to the trench formed by the furrowing disc  50  together, closing the trench and placing soil on top of a seed placed in the trench. The size of the pinching wheels  58  and the angle at which the wheels  58  are held relative to each other can be adjusted in any suitable way that allows the pinch wheels  58  to close the formed trench as the row unit  24  is carried across the field. 
         [0029]    Referring now to  FIG. 4 , the closing assembly  54  is shown with only the pneumatic cylinder  56  connected to an axle assembly  72  of the pinch wheels  58  so that the pneumatic cylinder  56  can provide down force to the pinch wheels  58  through the axle assembly  72 . The axle assembly  72  can have a main section  74  that connects to both pinch wheels  58 , allowing the pinch wheels  58  to be carried together along with the axle assembly  72 . The pinch wheels  58  can be connected to the main section  74  by axle bolts  76  placed through openings  78  of the pinch wheels  58  so that the pinch wheels  58  can be connected to the main section  74  without preventing rotation of the pinch wheels  58  as the row unit  24  is carried across the field. The pneumatic cylinder  56  can be connected to the main section  74  by a first biasing connection feature  80 , shown as a connection bar, that is connected to the main section  74  and allows for force exerted on the connection bar  80  to be transferred to the main section  74  and connected pinch wheels  58  since the pneumatic cylinder  56 , as shown, is fixedly attached to the mounting body  52 . 
         [0030]    The axle assembly  72  can also include a pair of axle arms  82  connected to the main section  74  and pivotally connected to the mounting body  52  by a pivot pin  84  extending through openings  86  formed in each plate  66  of the mounting body  52 , with the pivot pin  84  defining a pivot point on the mounting body  52  that the axle arms  82  can pivot about. The axle arms  82  can be laterally spaced apart so that each axle arm  82  is adjacent to one of the pinch wheels  58  and helps limit relative lateral movement of the pinch wheels  58  as the row unit  24  is carried across the field. As the axle arms  82  can pivot about the pivot pin  84  and are connected to the main section  74 , the axle arms  82  allow the pinch wheels  58  to pivot about the pivot pin  84  as the row unit  24  is carried across the field. Force applied to the axle assembly  72  by the pneumatic cylinder  56  can therefore cause or prevent pivoting of the pinch wheels  58  about the pivot pin  84  so that an amount of down force exerted on the pinch wheels  58  toward the ground can be controlled. While two separate axle arms  82  are shown as connected to the main section  74  and pivot pin  84 , it is contemplated that a single axle arm can take the place of the two separate axle arms  82 . 
         [0031]    Referring now to  FIG. 5 , the closing assembly  52  shown in  FIGS. 2-4  is illustrated with the compression spring  68  as the biasing element, rather than pneumatic cylinder  56 , connected to the mounting body  52  and axle assembly  72 . Unlike the pneumatic cylinder  56  shown in  FIGS. 2-4 , the compression spring  68  is not shown as being connected directly to the mounting body  52 , but can be connected to a pair of connection plates  88  that are attached to the mounting body  52 . As can be seen in  FIG. 5 , the connection plates  88 , which can together form a pushing mount section, can be connected to the mounting body  52  by bolts  90  extending through openings  92  (shown in  FIG. 4 ) formed in the mounting body  52  as well as pins  94  extending through the openings  61  formed in the mounting body  52  where the pneumatic cylinder  56  was shown as being connected to the mounting body  52  in  FIGS. 2-4 , allowing for easy biasing element conversion from the pneumatic cylinder  56  to the compression spring  68 . The connection plates  88  can each have adjustment openings  98 A,  98 B, and  98 C, which can also be referred to as mounting features, formed through that can be aligned to allow for a spring bolt  100  to extend through an opening (not seen) formed in an end  102  of the compression spring  68  and aligned adjustment openings, such as adjustment openings  98 B shown in  FIG. 5 , to connect the compression spring  68  to the connection plates  88 . While the mounting features of the connection plates  88  are shown as adjustment openings  98 A,  98 B, and  98 C, it should be appreciated that other mounting features can be included on the connection plates  88  to connect the compression spring  68  to the mounting body  52  and that the adjustment openings  98 A,  98 B, and  98 C can also be formed in the plates  66  of the mounting body  52 . As can be seen, the connection plates  88  can be angled relative to the mounting body  52  such that the adjustment openings  98 A,  98 B, and  98 C are vertically above the pivot pin  84  so the compression spring  68  can exert downward force on the axle assembly  72 . The adjustment openings  98 A,  98 B, and  98 C can be formed in the connection plates  88  so that each of the adjustment openings  98 A,  98 B, and  98 C has a different vertical height relative to the pivot pin  84 , allowing for varying amounts of downward force to be exerted on the axle assembly  72  by the compression spring  68  by adjusting which adjustment openings  98 A,  98 B, or  98 C is used to connect the compression spring  68  to the connection plates  88 . The compression spring  68  can have another end  106  opposite the end  102  that is connected to a compression spring connector  108 , which can also be referred to as a biasing connection feature, which is bolted to one or both axle arms  82 , connecting the compression spring  68  to the main section  74  of the axle assembly  72  and allowing the down force produced by the compression spring  68  to be exerted on the pinch wheels  58 . 
         [0032]    Referring now to  FIG. 6 , the closing assembly  54  is shown with the extension spring  70  as the biasing element connected to the axle assembly  72 , rather than pneumatic cylinder  56  or compression spring  68 . As can be seen, the extension spring  70  can have a first end  110  held in an opening  112 , which can be referred to as a mounting feature, formed in a connecting tab  114 , which can also be referred to as a pulling mount section, that is attached to the mounting body  52  and a second end  116  held in an opening  118  of an extension bar  120 , which can also be referred to as a biasing connection feature, that is connected to the axle arms  82  of the axle assembly  72 . This configuration allows tension from the extension spring  70  to pull the extension bar  120  toward the connecting tab  114 , which will also pull the axle arms  82 , main section  74 , and pinch wheels  58  toward the connecting tab  114  due to interconnections between the elements. While the extension spring  70  is shown as being connected to the connecting tab  114  attached to the mounting body  52 , the extension spring  70  can also be directly connected to the mounting body  52  or elsewhere in the row unit  24  such that it can apply a down force to the axle assembly  72  and connected pinch wheels  58 . Since the force applied to the pinch wheels  58  by the extension spring  70  is a tensile force, the extension spring  70  should have its first end  110 , which is not connected to the axle assembly  72 , held below the pivot pin  84  so the tensile force applied to the axle assembly  72  is directed in a downward direction toward the field as the row unit  24  is carried across the field. It should be appreciated that any type of extension spring can be used as extension spring  70  and the end of the extension spring that is not connected to the axle assembly  72  can be held in a variety of adjustable positions to change the amount of down force that the extension spring  70  applies to the axle assembly  72 . 
         [0033]    Taken together, it should be apparent that the axle assembly  72  connected to the pinch wheels  58  can convertibly and readily connect to the various biasing elements  56 ,  68  and  70  described herein with few, if any, modifications to the closing assembly  54  necessary to accommodate connection to the various biasing elements  56 ,  68  and  70 . This allows for the closing assembly  54  to readily incorporate all three types of biasing elements  56 ,  68  and  70  to provide down force to the pinch wheels  58  without changing the axle assembly  72  connecting the pinch wheels  58 . 
         [0034]    While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.