Abstract:
A forward folding implement is provided. The implement includes a telescoping tongue to allow forward folding wings of the implement. At one end of the tongue are positioned transport wheels that are used to level the height of the frame during planting to keep the row units at determined heights of the single plant uniform depth, while also providing a support for the implement during transport of the implement. A transport wheel rotating assembly is provided to rotate the transport wheels about a pivot point such that the transport wheels will adjust the height of the implement, and also increase or decrease the length of the wheelbase between the tractor tires and the transport tires to increase the maneuverability and transportability of the implement both within a field and outside a field. The assembly includes a linkage and a cylinder connected to the implement.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to provisional application Ser. No. 61/667,486, filed Jul. 3, 2012, which is hereby incorporated in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to the field of agricultural equipment. More particularly, but not exclusively, the invention relates to a forward folding implement, such as a forward folding planter. 
     BACKGROUND OF THE INVENTION 
     As the power of tractors and agricultural efficiency has increased, agricultural implements such as planters have increased in span, or width, to accommodate larger numbers of individual row units. Large planters generally include a main frame having a forward hitch assembly for drawing by a tractor and left and right wing sections pivotally attached to a portion of the main frame. The pivoting wing connections allow the wings to fold relative to the main frame for transport and storage of the planter. Early planters pivotally displaced the wings vertically to reduce planter width and provide clearance for transport through narrow spaces. 
     However, as the size of planters has increased, planter wings are generally folded in a forward direction to accommodate longer planter wings. This evolution has necessitated the incorporation of telescoping hitch assemblies and specific folding functions to accommodate planter wings of increased length. The telescoping hitch assemblies allow components of the hitch to be inserted within each other to vary the length between the hitch and the main frame. Therefore, the longer the wing sections, the longer the tongue will have to telescope to accommodate folding of the wings. This causes the transport wheels of the main frame to be extended away from the tractor. 
     As the planters are getting larger and heavier, it is becoming more difficult to be able to transport these machines to and from the field. Forward folding planters are prone to extreme hitch weight on the tractor and a large turning radius due to the long wheelbase between the tractor tires or tracks and the planter transport tires. This long wheelbase is because the transport tires of the planter are also used to set the height of the frame during planting to keep the row units at a height so the machine will plant at a uniform depth. The ideal location for the tires to level the frame height is between the row units. This location of the tires also provides that the planter does not account for negative hitch weight on the tractor when the planter is unfolded and the row units are off the ground. 
     Methods exist to shorten the wheelbase between the tractor tires and the planter transport tires. For instance, some planters include a sliding transport axle at the main frame of the planter. The axle is able to slide along the tongue to move toward and away from the rear of the tractor to alter the wheelbase. However, it can be very difficult to cause the axle to slide, especially when seed, fertilizer, insecticide, or other material weighs down the planter. The sliding action can cause increase wear and stress to the main frame of the implement, while also adding complexity to the machine. Furthermore, as the components of planters are commonly made from metals, there exists a chance that rusting or deformation could occur, which could prevent the axle from being able to slide along the tongue. 
     U.S. Pat. No. 6,408,950 to Shoup (the &#39;950 patent) discloses a planter having an independent support wheel assembly that is slideable towards the a new center of gravity after the frame has moved from an extended or working position to a folded or transport position. However, the &#39;950 patent includes the use of two separate motor mechanisms and wheel systems. Each of the motor mechanisms includes separate cylinders to raise and lower separate wheels. Therefore, one wheel may be lowered while the other is raised. However, the wheels must be raised and lowered individually. The separate motor mechanisms, wheels, and cylinders will also take up much space and will add a great deal of weight to the planter. The addition of multiple moving assemblies and parts also increases the chances that a moving component can fail or become damaged, which will affect the use of the planter. The multiple moving parts also increase the cost and complexity of the machine and the operation thereof. 
     Therefore, there is a need in the art of agricultural equipment for a method and apparatus for adjusting the wheelbase length between tractor wheel and implement transport wheel and accommodating a shift of the center of gravity of the implement that is simple to operate. There is also a need in the art for a method and apparatus for adjusting the wheelbase length and accommodating a shift of the center of gravity that will not increase the weight and cost of the implement, while also being effective. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object, feature, and/or advantage of the present invention to overcome deficiencies in the art. 
     It is another object, feature, and/or advantage of the present invention to provide an implement with an adjustable wheelbase length. 
     It is yet another object, feature, and/or advantage of the present invention to provide an implement with a transport wheel assembly capable of accommodating a shift of the center of gravity from movement of the wings between an extended, working position and a folded, transport position. 
     It is still yet another object, feature, and/or advantage of the present invention to provide a forward folding implement with a rotatable transport axle. 
     It is a further object, feature, and/or advantage of the present invention to provide an agricultural implement that includes a transport axle capable of rotating approximately 150°. 
     It is still a further object, feature, and/or advantage of the present invention to provide an agricultural implement including a wheel arm extending from a transport axle that will change the wheelbase length by 1.5 times the wheel arm length. 
     It is yet a further object, feature, and/or advantage of the present invention to provide an agricultural implement including a rotatable transport axle that is operated by a single cylinder and linkage. 
     It is another object, feature, and/or advantage of the present invention to provide an agricultural implement having a transport axle movable between a planting position, turning position, and a transport position. 
     These and/or other objects, features, and advantages of the present invention will be apparent to those skilled in the art. The present invention is not to be limited to or by these objects, features and advantages. No single embodiment need provide each and every object, feature, or advantage. 
     The invention includes a forward folding implement attached to a tractor. The implement includes a hitch, a telescoping tongue, a main frame including an axle, and wheels extending from the main frame and axle. The implement also includes wings and a plurality of row units at the main frame and wings. Because the ideal location of the transport wheels is between the row units during planting, the wheelbase length of the planter is extended. To reduce the wheelbase between the planter and tractor, the planter support wheels need to move forward towards the hitch during transport. To accomplish this shorter wheelbase, the axle that connects the transport tires will rotate close to 150 degrees underneath the planter. The rotation can decrease the tractor/planter wheelbase by 1.5 times the wheel arm length. 
     According to an exemplary embodiment of the present invention, a forward folding implement having a field use configuration and a transport configuration is provided. The implement includes a telescoping tongue having a first end including a hitch and an opposite second end. A main frame is positioned at the second end of the tongue and includes a main axle and a plurality of transport wheels extending from the main axle. First and second wings extend from the main frame and include a plurality of wing wheels extending therefrom. A transport wheel rotating assembly is positioned at the main frame and comprises a linkage attaching the transport wheels to the main frame and a cylinder operatively attached to the linkage. The transport wheel rotating assembly is configured to move the transport wheels between a retracted position for the field use of the implement wherein the transport wheels are positioned rearward of the main frame, and a transport position wherein the transport wheels are positioned frontward of the main frame. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a forward folding implement according to the present invention with the implement in a planting position. 
         FIG. 2  is a side elevation view of the implement of  FIG. 1  with the main or transport wheels in a planting position. 
         FIG. 3  is a side elevation view of the implement of  FIG. 1  with the main or transport wheels in a field turn position. 
         FIG. 4  is a side elevation view of the implement of  FIG. 1  with the transport wheels in a transport position without axle rotation. 
         FIG. 5  is a view similar to  FIG. 4 , but with axle rotation of the transport wheels. 
         FIG. 6  is a perspective view of the implement of  FIG. 1  with the wings and transport wheels in a transport position and with axle rotation. 
         FIG. 7  is an enlarged side view of the transport wheel rotating assembly of the implement of the present invention being in a planting position. 
         FIG. 8  is an enlarged side view of the transport wheel rotating assembly of the implement of the present invention being in a transport position. 
     
    
    
     Before any independent features and embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of the construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a perspective view of a forward folding implement  10  according to the present invention with the implement  10  in a planting position. While the present invention shows the implement  10  to be a planter, it should be appreciated by those skilled in the art that the invention covers other types of implements, including but not limited to, nutrient applicators, plows, disks, and other agricultural equipment. However, for exemplary purposes, the invention will be described for a forward folding-type implement  10 , such as a forward folding planter. 
       FIG. 1  shows a forward folding planter  10  with a tongue  12 . The tongue  12  includes a first end  14  and an opposite second end  18 . At the first end  14  of the tongue  12  is a hitch  16 , The hitch  16  allows the implement  10  to be attached to a tractor (not shown) or other vehicle for pulling the implement  10 . The hitch  16  may be any hitch used in the industry. The tongue  12  may be a telescoping tongue such that the tongue  12  includes multiple sections that can be inserted and moved relative to one another such that the length of the tongue  12  can be varied. The telescoping of the tongue  12  may be further aided by the addition of tongue supports  20  on opposite sides of the tongue  12 . As will be discussed, the tongue supports  20  connect the first end  14  of the tongue  12  to first and second wings  32 ,  35  such that when the wings fold by operation of cylinders  24 , the supports  20  will extend one section of the telescoping tongue  12  to lengthen the tongue  12  so that the wings  32 ,  35  are able to be folded adjacent one another. 
     Positioned at or near the second end  18  of the tongue  12  is a main or central frame  22 . The main or central frame  22  extends generally perpendicular to the tongue  12 . The central frame also includes housing for main hoppers  26 . The main hoppers  26  house material, such as seed, insecticide, fertilizer, or the like, which is distributed through a system to individual row units. Therefore, a great deal of weight is located at the central frame  22 . The central frame includes central row units (not shown) extending from the rear of the central frame to distribute the material to a field. The central frame also includes a main axle  28  and transport wheels  30  extending from the main axle  28  and the main frame  22 . The transport wheels  30  support the main or central frame  22 , and also are the wheels that contact the ground when the implement  10  is transported to or from a field. 
     Extending from opposite sides of the central frame  22  are first and second wings  32 ,  35 . The first and second wings  32 ,  35  generally mirror one another, and therefore, only one wing will be described. It should be appreciated that the opposite wing will include generally the same components. The first wing  32  includes a first frame  33  extending separate from, but extending generally in the same plane as the main frame  22 . A plurality of row units (not shown) will be connected to the first frame  33 . The row units of the first wing  32  are generally the same as row units of the central frame  22  and that of the opposite wing  35 . The number of row units used with an implement  10  may vary depending on the size of the implement  10 , the requirements of the field, the type of material being distributed to the field, and the like. Also extending from the wing frame  33  are wing wheels  38 . The wing wheels  38  support the outer ends of the wings  32 ,  35  and allow the implement  10  to be moved without the row units penetrating the ground when turning in the field, crossing waterways or the like. 
       FIGS. 1 and 2  further show the implement  10  of the present invention in a planting position. When the implement  10  is in the planting position, the wheels, including the transport wheels  30  and the wing wheels  38 , are retracted to a position where they are generally rearward of the main frame  22  and the wing frames  33 ,  36 . The positioning of the wheels is such that the wheels will be raised to allow the row units to sufficiently contact and penetrate the ground of the field. However, it should be appreciated that the wheels will need to be able to move from the planting position to other positions in order to move the implement  10  both within the field and outside of the field. 
     As shown in  FIG. 3 , the wheels  30 ,  38  of the implement  10  have been adjusted such that the implement  10  is in a field turn position. The wing wheels  38  include cylinders or other moving mechanisms to move the wheels between the planting position and the field turn position, as shown in  FIGS. 2 and 3 . Furthermore, the transport wheels  30  include a transport wheel rotating assembly  40  that allows the transport wheels  30  to be rotated relative to the main frame  22  about the main axle  28  and including more rotational movement than that of the wing wheels  38 . The transport wheel rotating assembly  40  includes a cylinder  52  connecting between the main frame  22  and the linkage  42 . The configuration and use of the linkage  42  will be discussed more below. The cylinder  52  is extended from the position of  FIG. 2  to that of the position in  FIG. 3  such that the transport wheels  30  are rotated in a counterclockwise direction such that the wheels contact the ground and then begin to lift the row units away from the ground as shown by the arrow generally depicted as numeral  58 . Furthermore, the cylinder  52  and linkage  42  of the transport wheel rotating assembly  40  is sized such that the rotation of the wheels will lift the implement  10  off the ground such that the row units will no longer be in contact with the ground. 
     Furthermore, the number of cylinders  52  and rotating assemblies  40  may vary. The present invention contemplates that only one cylinder and linkage is required to rotate the transport wheels  30 . However, as shown in the figures, the invention also contemplates that more rotating assemblies  40  may be included, including a rotating assembly  40  for each of the transport wheels  30 . For example, when the implement  10  includes four transport wheels  30 , four rotating assemblies  40  can be included and connected between the frame and the wheels to rotate the wheels between field use, turning, and transport configurations. Therefore, it should be appreciated that generally any number of rotating assemblies, including cylinders and linkages, may be used and all variations of the like are to be considered part of the invention. 
     In the position shown in  FIG. 3 , the tractor is more easily able to turn within a field, as the row units do not provide drag and are not subjected to destructive side loads that would restrict turning. It should be appreciated by those skilled in the art that while  FIG. 3  shows the transport and wing wheels at an angle relative to the frames and implement  10 , the purpose of putting the implement  10  in a field turn position is to raise the row unit from the ground, and therefore, any position of the wheels such that the row units are positioned away from the field is acceptable for a field turn position. 
       FIGS. 4-6  show the implement  10  in a transport position with and without rotation of the transport wheels  30  about the main axle  28  by the transport wheel rotating assembly  40 . In these figures, the wings  32 ,  35  have been folded in a forward movement, i.e., rotated about a generally vertical axis. The wings  32 ,  35  are folded by forward folding cylinders  24  connected between the wings  32 ,  35  and the tongue  12  to move the wings  32 ,  35  with the first wing  32  and the second wing  35  on opposite sides of the tongue  12  and generally adjacent to one another. At this position, the wings  32 ,  35  may be locked in place such that they will be held in this position. The forward folding of the wings  32 ,  35  may be accomplished once the implement  10  is in a field turn position, e.g., the configuration shown in  FIG. 3 . As shown in  FIG. 4 , the raising of the row units off the ground allows the wings  32 ,  35  to be folded easier and without drag or other restrictions. However, when the implement  10  is in such a transport position such that the transport wheel  30  is still in a field turn position, the wheelbase or length from the hitch  16  to the transport wheels  30  is rather large. In addition, the length is even larger from the position of the tractor wheel to the position of the transport wheels  30 . Thus, the large wheelbase will make it more difficult for an operator to control the movement of the implement  10 , including turns. The larger a wheelbase, the wider a turn must be, which can decrease the safety of the turns outside of a field for both the operator and other traffic. 
     As shown in  FIGS. 5 and 6 , the present invention contemplates the use of a transport wheel rotating assembly  40  to rotate the position of the transport wheel  30  about the direction of the arrow  56 . The transport wheel rotating assembly  40  includes a linkage  42  attached to the main axle  28 , and a rotating cylinder  52  connected to the linkage  42 . One of the bars of the linkage  42  is a wheel arm  54  extending from the main axle  28  to the axle of the transport wheel  30 . Therefore, the transport wheel  30  rotates along with the wheel arm  54 . As shown, the transport wheel rotating assembly  40  may rotate the transport wheel  30  up to approximately 150° from the position of the transport wheel  30  in the planting position. The configuration of the linkage  42  and the length of the rotating cylinder  52  are such that the wheel base length may be shortened by a distance approximately 1.5 times the length of the wheel arm  54 . This reduction in length of wheelbase increases the maneuverability of the implement  10 , reduces the turning radius of the implement  10 , and creates a generally safer transport. By allowing the wheelbase length to be shortened with the transport wheel rotating assembly  40 , the present invention also accommodates for the wings  32 ,  35  being greater in length as the length of the wheelbase  10  may be shortened to compensate the forward shift of the center of gravity once the wings are in a folded position. Put another way, having longer wings  32 ,  35  would normally increase the wheelbase. The assembly  40  of the present invention would compensate for the longer wing length by reducing the otherwise added length by rotating the wheels. 
     Advantages of the present invention are numerous. As stated, the rotational movement of the transport wheel  30  from that shown in  FIG. 1  to that shown in  FIG. 4  reduces the wheelbase length, which is the length of the distance between the transport wheel  30  and the hitch  16  or the wheels of the tractor (not shown). This reduction of wheel base length increases the maneuverability of the implement during transport of the implement  10 . The use of the transport wheel rotating assembly  40  also accommodates a longer set of wings  32 ,  35 , which allows for the use of more row units on the wings  32 ,  35 . The use of more row units on the wings  32 ,  35  allows for more rows to be planted at one time, such that a farmer or operator is able to reduce the amount of time in the field during planting. In addition, as the wheelbase length may be considered to be shortened or lengthened by approximately 1.5 times the length of the wheel arm  54  by adjusting the length of said wheel arm  54 , the wheelbase length may be configured to be appropriate for different types of implements  10 . 
       FIGS. 7 and 8  are enlarged views of the transport wheel rotating assembly  40  of the present invention. As discussed, the transport wheel rotating assembly  40  includes a linkage  42  connected to the main axle  28  and a rotating cylinder  52  connected to the linkage  42 . The linkage  42  is a four bar linkage and includes a first bar  44 , second bar  46 , third bar  48 , and fixed link  50 . The fixed link  50  or frame may not be a discrete structural member, but rather can comprise a commonly understood component of the typical four bar linkage that extends between two cranks, in this case the first bar  44  and the third bar  48 , opposite the connecting rod. The bars of the linkage  42  are connected by pins  60  or other connecting devices, which allow the bars to rotate relative to one another. Therefore, each end of the bars  44 ,  46 ,  48  includes apertures therethrough such that the apertures of the bars will line up with one another to create the our bar linkage  42 . The construction of the linkage  42  and the lengths of each of the bars is such to allow for the rotation of the transport wheel  30  upon extension or retraction of the cylinder  52 . The extension of the cylinder  52  creates a rotational movement about the pivot or main axle  28  to move the transport wheel  30  from the planting position to a transport position, as well as positions therebetween. The amount of rotation can be varied by changing the lengths of the individual bars of the linkage  42 , as well as the size and length of the cylinder  52 . Furthermore, it should be appreciated that the cylinder  52  is sized such that it is able to rotate the transport wheels  30  with enough force to be able to lift the implement  10 , as was previously discussed. Furthermore, while it is preferred that the cylinder  52  be a hydraulic cylinder, other cylinders, such as pneumatic, electric, etc., may be used with the assembly and are contemplated by the present invention as well. 
     It should be appreciated by one skilled in the art that a transport wheel rotating assembly  40  be positioned at each of the transport wheels  30  at the main or central frame  22 . Each of the transport wheel rotating assemblies  40  can work in unison with one another to move or rotate the transport wheel  30  at the same time and rotation of velocity. Thus, each of the linkages  42  and cylinders  52  will be the same for each of the transport wheel rotating assemblies  40 . In addition, it is contemplated by the present invention that only one linkage  42  and cylinder  52  be contemplated to be used at the main or central frame  22  with the transport wheels  30  connected by a bar or other mechanism such that the one transport wheel rotating assembly  40  be used to rotate the transport wheels  30  from the planting position and all the way to the transport position. However, it is preferred that each wheel include its own linkage  42  and cylinder  52 . 
     As best shown in  FIGS. 7 and 8 , the third bar  48  of the linkage  42  may also be the wheel arm  54  connecting the transport wheel  30  to the pivot point or main axle  28 . Therefore, the length of the third bar  48  may be varied, with the length being longer than the actual third bar  48  of the linkage  42 . Thus, the length of the third bar  48  is considered to be the length between the pins  60 ,  61  in  FIG. 8 . However, the length of the wheel arm  54  is longer than the length of the third bar  48  of the linkage  42 . This length of the wheel arm  54  may be varied according to the size of the implement  10  and wings  32 ,  35 . As noted above, the length of the wheelbase will be adjusted by rotation of the transport wheel  30  such that the length may be shortened up to 1.5 times the length of the wheel arm  54 . Thus, as the length of the wheel arm  54  is adjusted, the length of the wheelbase will be adjusted as well. When an implement  10  includes longer wings  32 ,  35 , a longer wheel arm  54  will be required in order to shorten or decrease the length of the wheelbase to accommodate for the longer wings  32 ,  35 . 
     A transport wheel rotating assembly for an implement and a method of use has been shown and described. The present invention contemplates numerous variations, options, and alternatives, and is not to be limited to the specific embodiments described here. For example, the length of the bars of the linkage may be varied, the number of transport wheels and rotating assemblies may be varied, and the length of the wings and tongue may be varied as well. Furthermore, while the implement is shown to include central hoppers on the main frame that feed all the individual row units, it is further contemplated that the rotating assembly may be used with an implement including individual hoppers at each of the row units. Furthermore, it should be appreciated that the length and size of the rotating cylinder may be varied according to the amount of weight of the implement. Other changes are considered to be part of the present invention.