Abstract:
An agricultural implement includes a hitch boom to which a pair of wing booms is pivotably connected. The wing booms are designed to fold forward from an extended position to a transport position. The wing booms are supported above a surface by wheels that provide the aforementioned support when the wing booms are in an extended position as well as the transport position. Maintaining surface contact of the wheels in both positions reduces the load placed on the hitch to which the hitch boom is coupled as well as the hitch boom itself. Multi-link draft links are connected between the hitch boom and the wing booms to provide support for the wing booms when the wing booms are in the extended position. The relative length of the draft links dictates how far the hitch telescopes when the wing booms are folded to the stowed or transport position.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates generally to agricultural implements and, more particularly, to a forward folding planter having improved maneuverability and hitch loading when in a transport configuration. 
         [0002]    Agricultural planters generally consist of a hitch boom to which a pair of wing booms are coupled. The wing booms support a series of spaced seed units that deposit seed, fertilizer or other granular material onto a planting surface, e.g., farm field. Because of the relatively large wingspan of the wing booms, the planter frame will also include a pair of draft links. The draft links extend between the hitch boom and the wing booms, and are designed to add stability to the wing booms as the planter traverses the planting surface. In some planters, the wing booms are designed to fold forward against the hitch boom. For such forward-folding planters, the wing booms will typically be folded forward when the planter is ready for transport. That is, a planter generally has a working position in which the wing booms are fully extended away from the hitch boom and a transport position in which the wing booms are folded forward. In the transport position, the width of the planter is greatly reduced which is advantageous for exiting the planting surface and for storage of the planter. Additionally, when being shipped, the planter will be placed in its transport position. 
         [0003]    To expedite particulate matter deposition onto the planting surface, planter manufactures are adding length to the wing booms thereby allowing more seed units to be mounted along the length of the wing booms. As a result of the increases in length of the wing booms, the outer ends of the wing booms may undesirably extend past the hitch of the towing vehicle, e.g., tractor, when the planter is in the transport position. As such, large agricultural planters are typically used with telescoping rather than fixed length hitches. More particularly, the hitch boom is coupled to a telescoping hitch that is extended as the wing booms are folded forward. The telescoping hitch therefore provides clearance for the tractor when the outer ends of the wing booms come together. 
         [0004]    When the wing booms have been folded forward and engaged with the telescoping hitch, the telescoping hitch is lifted to provide clearance for the wheels that support the wing booms above the planting surface. This lifting of the hitch loads the rear wheels supporting the hitch boom and the hitch itself with a majority of the weight of the planter, which can result in overloading. In addition, it can be difficult to turn the planter when it is being towed as the elongation of the hitch to accommodate the folded wing booms greatly adds to the length of tow and thus the area required for cornering the planter. 
         [0005]    When the wing booms are folded forward, the draft links connected between the hitch boom and the wing booms cause the hitch boom to pull on the telescoping hitch to effectively extend the telescoping hitch to provide the aforementioned clearance for the wing booms. As such, the lengths of the draft links and their connection points to their respective wing booms dictate how far the telescoping hitch is extended. The farther out on the wing boom the connection point the more of the telescoping hitch that will be extended when the wing booms are folded forward. Therefore, the desired change in length, dictated by the amount of room required for the tractor to clear the wing booms when the booms are in the fully folded position, dictates the position the connection point of the draft links to the wing booms. However, the amount of length required to extend the hitch often results in a connection point that is structurally insufficient to support the draft links when the wing booms are in their working position. As such, it is generally necessary to use heavy hinges to connect the draft links to the wing booms and undesirably expose the wing booms to greater stress. 
         [0006]    Therefore, there is a need for an agricultural planter having a forward folding frame that places less load on the frame itself and the hitch when in a transport configuration. There is also a need for an agricultural planter having improved maneuverability when being transported. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is directed to a forward folding agricultural planter particularly well suited for use with a telescoping hitch coupled to a towing vehicle, such as a tractor. The planter has a pair of wing booms pivotably coupled to a hitch boom and that fold forward to stow the wing booms in a transport position. Draft links are connected between the hitch boom and the wing booms to provide stability for the wing booms when the wing booms are in an extended, working position but also dictate how far the telescoping hitch is extended when the booms are folded forward. 
         [0008]    The wing booms are supported by respective wheels assemblies having wheels that may be rotated downward as the wing booms are folded forward and then allowed to caster as the planter is towed. In this regard, the wheels support the wing booms when the wing booms are in the extended working position as well as the folded transport position. Thus, less load is placed on the hitch as well as the rear wheels that support the hitch boom when the planter is in the transport position. 
         [0009]    The wing booms are coupled to the hitch boom by a mounting arrangement that allows the wing booms to rotate or pivot upward relative to the hitch boom when the wing booms are folded forward. Rotating the wing booms slightly upward provides clearance for the seed units that are carried by the wheel booms. To maintain engagement of the wheel assemblies with the planting surface as the wing booms are rotated upward, the wheel assemblies are rotated downward. Thus, as noted above, the wheels maintain continuous engagement with the planting surface as the wing booms are folded from the working position to the transport position. 
         [0010]    The placement of the draft links is optimized so that the telescoped hitch is extended by a minimal amount necessary for the outer ends of the wing booms to clear the rear of the towing vehicle when the wing booms are in the fully folded position. 
         [0011]    The draft links each include an inner link member and an outer link member connected to one another by a hinge that allows the link members to pivot. The inner link member is connected to the hitch boom and the outer link member is connected to the wing boom. An actuator such as a hydraulic cylinder is connected between the wing boom and the outer link and is designed to draw the outer link inward against the wing boom when the wing boom is being folded forward. As a result, the link members fold upon themselves as the wing booms are being folded forward to the transport position. 
         [0012]    The hitch boom includes a wing boom retainer that loosely captures the outer ends of the wing booms when the wing booms are in the fully folded position. The retainer is constructed to retain the outer ends yet allow limited vertical and lateral movement, e.g., oscillation, of the wing booms as the planter is being transported. 
         [0013]    Thus, it is one object of the invention to provide a forward folding planter that places less stress on the hitch of the towing vehicle when the planter is being towed in transport. 
         [0014]    It is another object of the invention to provide a planter that is more maneuverable when in transport yet that does not impact the rigidity required during working, i.e., seeding or fertilizing. 
         [0015]    It is yet a further object of the invention to provide a planter for use with a telescoping hitch that extends the hitch by a minimal amount necessary when the planter is folded forward to a transport position. 
         [0016]    Other objects, features, and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0017]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout. 
           [0018]    In the drawings: 
           [0019]      FIG. 1  is an isometric view of an agricultural planter hitched to a tractor; 
           [0020]      FIG. 2  is a partial top plan view of the planter of  FIG. 1  showing a hitch boom and a wing boom in an extended position. 
           [0021]      FIG. 3  is an isometric view of the portion of the planter show in  FIG. 2  in a folded transport position; 
           [0022]      FIG. 4  an enlarged top plan view of the planter taken along line  4 - 4  of  FIG. 3 ; 
           [0023]      FIG. 5  is an isometric view of the planter shown in  FIG. 4 ; 
           [0024]      FIG. 6  is an isometric view of the planter similar to the view shown in  FIG. 5  with a wing boom retainer tilted to a boom release position; 
           [0025]      FIG. 7  is an isometric view of the planter shown in  FIG. 2  with a draft link in a partially folded position; 
           [0026]      FIG. 8  is an enlarged isometric view of a portion of the draft link and wing boom shown in  FIG. 7 ; 
           [0027]      FIG. 9  is an enlarged isometric view of a wing boom wheel assembly of the planter taken along line  9 - 9  of  FIG. 1 ; 
           [0028]      FIG. 10  is an isometric view of an underside of the wing boom assembly shown in  FIG. 9 ; 
           [0029]      FIG. 11  is an isometric view of an underside of the wing boom assembly in a transport position; 
           [0030]      FIG. 12  is a front elevation view of the wing boom assembly in the transport position; and 
           [0031]      FIG. 13  is a top isometric view of the wing boom assembly in the transport position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    The present invention is directed to an agricultural planter  10  particularly suited for use with a telescoping hitch  12  carried by or otherwise coupled to a tractor  14  or similar towing vehicle as shown in  FIG. 1 . The planter  10  includes a frame  16  generally comprised of a hitch boom  18  that connects to the telescoping hitch  12  and a pair of wing booms  20 ,  22  that are connected to the hitch boom  18 . The wing booms  20 ,  22  are connected to the hitch boom  18  at a mount  24  in a manner that allows the wing booms  20 ,  22  to fold forward. Although not pictured, seed units, seed/fertilizer hoppers, cabling, and hydraulics are mounted to the hitch boom  18  and the wing booms  20 ,  22  to control the deposition of seed, fertilizer, insecticide, herbicide, and the like onto the planting surface. 
         [0033]    As will be appreciated by one skilled in the art, the hitch boom  18  is generally aligned with the hitch  12  and defines a central axis that generally runs parallel with the direction of travel of the tractor. In this regard, wing boom  20  constitutes a “left-side” wing boom and wing boom  22  constitutes a “right-side” wing boom. The wing booms  20 ,  22  are oriented symmetrically about the hitch boom  18  and are similarly constructed. As such, for purposes of description, the left-side wing boom  20  will be described but it is understood that the right-side wing boom  22  is of similar construction. 
         [0034]      FIG. 2  shows the wing boom  20  in its extended, working position. In this position, the wing boom  20  is generally perpendicular to the path of travel and the central axis of the hitch boom. The wing boom  20  is supported above the planting surface by wheels  26 ,  28 . As will be described more fully below, the wheels  26 ,  28  provide support for the wing boom  20  when the boom  20  is in its extended position as well as its retracted, transport position, which is shown in  FIG. 3 . A draft link  30  is connected between the hitch boom  18  and the wing boom  20  at a connection point  33  forward of the mount  24 . The draft link  30  provides structural support for the wing boom  20  when the wing boom  20  is in the fully extended position. As will be described more fully below, the draft link  30  has a pair of link members  32 ,  34  connected to one another by a knuckle  36  that allows the link members  32 ,  34  to fold relative to one another when the wing boom  20  is folded forward to its transport position. 
         [0035]    The hitch boom  18  includes a coupler  38  as known in the art for coupling the hitch boom  18  to the telescoping hitch  12 . The hitch boom  18  is supported above the planting surface by a set of wheels  40 , which in the illustrated embodiment includes two pairs of wheels, with a pair positioned adjacent each side of the hitch boom  18 . The hitch boom  18  extends along a central axis of the planter  10  that is aligned with the hitch of the  12  of the tractor. The wheels  40  are coupled to a central wheel standard  42  that forms part of a steering/elevator assembly that is pinned to the mount  24  at a near vertical pin  46 . 
         [0036]    Wing boom  20  has a center boom  44  that is pinned to the mount  24  at a pin  48  and an inner boom  50  that is pinned to the center boom  44  by horizontal longitudinal pin  52 . The inner boom  50  is pinned to an outer boom  54  by a pin  56 . The interconnection of the inner and outer booms  50 ,  54  allows the outer boom  54  to lifted and folded over the inner boom  50 . An inner actuator  57  that in one embodiment includes a hydraulic cylinder  58  is connected to the center boom  44  and a ram  60  is pinned to the mount  24  at pin  62 . In addition to inner actuator  57 , a draft link actuator  64  is provided that in one embodiment includes a hydraulic cylinder  66  connected to the inner boom  50  and a ram  68  connected to outer draft link member  34 . 
         [0037]    When rams  60  and  68  are fully extended, the wing boom  20  is in the fully extended position, as illustrated in  FIG. 2 . However, when the rams  60  and  68  are retracted, the wing boom  20  is pulled inwardly toward the hitch boom  18  about pin  48  and eventually adjacent the hitch boom as shown in  FIG. 3 . More particularly, the rams  60  and  68  are retracted simultaneously until ram  68  is fully retracted. Ram  68  draws the outer link member  34  inward toward the inner boom  50  as the outer link member  34  is able to pivot relative to the inner link member  32  at knuckle  36 . The ram  68  draws the outer link member  34  until the knuckle  36  abuts against the inner boom  50 . With the knuckle  36  abutting the inner boom  50 , the ram  60  continues to retract until the booms are adjacent and generally parallel to the hitch  12 . As will be explained in greater detail below, the wheels  26 ,  28  rotate under the wing boom  20  when the wing boom  20  is being moved to its retracted position to provide clearance for seed units mounted to the wing boom  20 . Thus, as the wing boom  20  is elevated by the wheels  26 ,  28  rotating under the wing boom  20 , the rear end of the hitch boom  18  is elevated relative to the hitch  12  of the tractor  14 . As a result, the hitch boom  18  is angled downwardly toward the hitch  12 . The near vertical pin  46  is angled in such a way that as the wing boom  20  swings ahead, the angling of the wing boom  20  causes the outer end of the wing boom  20  to angle up relative to the hitch  12 . So, while the telescoping hitch boom  18  angles downward, the booms are level and aligned, as illustrated in  FIG. 3 . This is particularly advantageous for transportation and shipping purposes. 
         [0038]    As shown in  FIG. 3 , when the planter  10  is in the transport position, the draft link  30  is folded alongside the hitch boom  18  and wing boom  20  is folded ahead. The draft link  30  is connected to the hitch assembly  38  rather than connecting the telescoping hitch  12  to the hitch boom  18  because there will motion in the inner boom relative to the center boom as undulating terrain is encountered in transport. As such terrain is encountered, there will be small changes in the position and the draft link  30  will shift slightly from front to back. When this occurs, crank  70  will oscillate relative to pin  72 . 
         [0039]    With additional reference to  FIGS. 4-6 , a wing boom retainer  74  is mounted to the hitch boom  18  and includes a vertical post  76  and a retainer plate  78  that defines a U-shaped channel  80  sized to receive and hold boom plate  82  mounted to the wing boom  20 , and in particular, a wheel mount assembly  84  to which wheel  28  is coupled by a wheel standard  86 . The retainer plate  78  is designed to retain the boom plate  82  adjacent the post  76  but allow limited vertical and lateral movement of the wing boom  20  during transport. In this regard, locking of the wing boom  20  is not solely controlled by the boom folding actuators  57  and  64 . 
         [0040]    The U-shaped retainer  78  is journalled at pin  88  to the hitch boom  18  and fore of post  76 . A hydraulic actuator  90  is mounted to the hitch boom  18  with pin  92  and the retainer  78  at pin  94  such that when the actuator  90  is extended the retainer  78  is pushed forward to envelop post  76  and plate  82 , as illustrated in  FIGS. 4-5 . When actuator  90  is retracted, the retainer  78  is pulled forward and away from the post, as illustrated in  FIG. 6 . Thus, when the wing boom  20  is folded forward, actuator  90  is retracted until the boom plate  82  is generally flat against the post  76 . The actuator  90  is then extended to push the retainer  78  rearward to capture the post  76  and the boom plate  82 . 
         [0041]    As referenced above and with additional reference to  FIGS. 7-8 , a draft link  30  generally comprised of an inner link member  32  and an outer link member  34  connected between the hitch boom  18  and the wing boom  20 . The inner link member  32  and the outer link member  34  are connected to one another by a knuckle  36  that allows the outer link member  34  to pivot or fold forward relative to the inner link member  32  when the actuator  64  draws the outer link member  34  toward the wing boom  20 . In this regard, one end of the outer link member  34  is connected to the knuckle  36  and the opposite end of the link member  34  is pinned to the wing boom at pin  96 . In a similar fashion, actuator  64  includes a cylinder  66  connected to the wing boom at pin  98  and a ram  68  linked with cylinder  66  and connected to the outer link member  34  at pin  100 . 
         [0042]    Thus, when the wing boom  20  is in the working position, shown in  FIG. 2 , actuators  57  and  64  are in the fully extended position. When the wing boom is to be placed into the transport position, both actuators are retracted thereby causing the outer link member  34  to pivot forward and the wing boom  20  to pivot forward. The actuator  64  will retract until the knuckle  36  is against the wing boom  20 , as shown in  FIG. 8 . Thereafter, the actuator  57  will continue to retract causing further folding of the wing boom  20  and the outer link member  34  until the transport position, shown in  FIG. 3 , is reached. 
         [0043]    One skilled in the art will therefore appreciate that the knuckle  36  provides two axis of rotation. More particularly, the outer link member  34  is journalled to the knuckle  36  via a vertically oriented pin  102  and the inner link member  32  is journalled to the knuckle  36  via a generally horizontal pin  104 . In addition, the relative lengths of the inner link member  32  and the outer link member  34  dictate the amount of telescoping of hitch  12 . Thus, the lengths of the members  32 ,  34  can be tailored on a per application basis to accommodate the desired location of support on the wing boom  20  yet also accommodate the amount of extension of the hitch  12  needed to clear the tractor  14  when the wing boom is in the transport position. 
         [0044]    Referring now to  FIGS. 9-13 , the wheels  26 ,  28  are designed to caster as the wing boom  20  is moved from the working position to the transport position. This castering allows the wing boom to “walk” forward as it is being fold to the transport position. While  FIGS. 9-13  only show wheel  26  it is understood that wheel  28  is similar constructed. 
         [0045]    Wheel  26  is connected to the wing boom  20  by a wheel mount  106 , which is connected to the wing boom in a known manner. The wheel  20  is centered about an axle  108  that is pinned to a caster frame  110 . The caster frame  110  is connected to a wheel standard  112  that is connected to the wheel mount  106  via arm  114 . The arm  114  may be pivoted by an actuator  116  that is pinned to the arm  114  at pin  118  is pinned to the wheel mount  106  at pin  120 . In a preferred embodiment, the actuator  116  is a hydraulic cylinder and ram combination similar to the hydraulic actuators described above. When the wing boom is in the field position, the wheel  26  is locked so as to travel along a fixed line parallel to the path of travel of the hitch boom. However, when the wheel  26  is unlocked, the wheel  26  may caster thereby providing support for the wing boom  20  as the wing boom  20  is folded forward. In this regard, the wheel  26  maintains support of the wing boom  20  when the wing boom  20  is in the working and transport positions. 
         [0046]    The wheel  26  is locked by a wheel lock assembly  122  that generally includes a locking plate  124  mounted atop the caster frame  110  and a lock  126  connected to the wheel standard  112 , as best shown in  FIG. 11 . The lock  126  is connected to the wheel standard  112  by a pair of pins  128  and includes a post  130  sized to be received by locking plate  122 . More particularly, the locking plate  124  has a U-shaped notch  132  that receives the post  130  when the lock is pivoted downward. When the post  130  is seated in the notch  132 , the caster plate  124  and thus the caster frame  110 , connected thereto, cannot rotate about standard  112  and therefore locks the wheel  26  into a non-caster position. 
         [0047]    As best shown in  FIG. 12 , an unlocker bar  134  is pinned to the lock  126  at pin  136 . When the hydraulic actuator  116  is activated and the arm  114  pivoted upward, the wheel standard  112  is pulled toward the rear of the wing boom  20  effectively causing the wheel standard  112  to be placed in a vertical position, such as shown in  FIGS. 11-13 . In addition, as the wheel standard  112  moves to the vertical or upright position, the unlocker bar  134  encounters a stop bar  138  mounted to the underside of the wheel mount  106 . This forces the unlocker bar  134  to load pin  136 . The downward force causes the lock  126  to pivot upward about pin  128  thereby releasing the post  130  from notch  132  of the caster plate  124 . The actuator  116  holds the wheel standard  112  in the upright position and the wheel  26  is free to caster as the wing boom  20  is moved to the transport position. When the wing boom  20  is in the transport position, the castering of the wheel  26  allows the wheel  26  to travel parallel to the path of travel of the hitch boom  18  but effectively rotated ninety degrees from its position when the wing boom  20  is in the working position. 
         [0048]    When the wing boom  20  is moved from the transport position to the working position, the wheel  26  will similarly caster. Once the wing boom  20  is in the working position, the actuator  116  can lower the wheel  26  to its working position thereby releasing the load on pin  136 . As a result, the lock  26  will pivot downward and the post  130  will be received in the notch  132  to lock the wheel into the working position. 
         [0049]    Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.