Abstract:
An apparatus for reducing the stresses placed on a cantilevered component mounted to a rigid frame includes cushioned bushings coupling the cantilevered component to a rigid frame. As the cantilevered component is loaded due to bending moments, the cushioned bushings flex and cushion the cantilevered component. The cantilevered component is retained within the bushing using hardware that allows the cantilevered component to float as needed to further reduce stresses and strains thereon.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates generally to tillage implements and, more particularly, to tillage implements using rotary blades or reels that are mounted to a rigid frame by cantilevered members, such as spindles. 
         [0002]    It is well known that to attain the best agricultural performance from a piece of land, a farmer must cultivate the soil, typically through a tilling operation. Common tilling operations include plowing, harrowing, and sub-soiling. Modern farmers perform these tilling operations by pulling a tilling implement behind a motorized tractor. Depending on the crop selection and the soil conditions, a farmer may need to perform several tilling operations at different times over a crop cycle to properly cultivate the land to suit the crop choice. 
         [0003]    In one type of tilling operation, rows or gangs of discs are pulled through soil at depths between 3 and 6 inches to break up clods or lumps of soil, as well as old plant material to provide a more amenable soil structure for planting and level the soil surface. 
         [0004]    The configuration of the tilling implement gangs and their constituent discs will determine the quality and quantity of the passes required to effectively till an area of soil. For example, a gang of parallel flat discs pulled through the soil, oriented such that their axis of revolution is perpendicular to the direction of pull, will not be very effective at tilling the soil. To improve the tilling action, those skilled in the art have attempted to change the angle at which the gang is oriented. However, an increased gang angle can cause complications. The increased gang angle will leave large clods of soil that may require multiple passes to pulverize. Additionally, the side pressure of the soil against the sides of flat discs or discs having only a shallow concavity of 1.25 to 1.69 inches will often break the discs. To increase disc strength, the disc can be made to be more concave. However, increasing the concavity of the discs to improve their strength promotes the formation of an undesirable compaction layer. 
         [0005]    Thus, tilling implements involving discs have a number of drawbacks. First, multiple passes of the tilling implement over the same area of soil may be required to properly cultivate the soil and cut through heavy crop residue. If multiple passes are required, then the farmer will incur increased costs associated with the amount of time and fuel required to prepare the seedbed. Known tilling implements are limited to speeds below approximately 6 miles per hour. Speeds in excess of approximately 6 miles per hour will vertically lift the tilling implement, resulting in the blades engaging the soil by less than 3 to 6 inches. If this occurs, the blades will not effectively till the soil or, if the blades are forced to remain in the soil, it can result in increased disc failure due to the increased pressure applied to the discs by the soil at greater velocities. 
         [0006]    Second, existing cultivators compact the soil under the prepared seedbed. This layer of compacted soil inhibits plant germination, root growth, and crop yield. The presence of a compacted layer of soil may require an additional tillage operation such as plowing to break up the compacted earth in order to avoid the problems of poor water absorption and weak anchoring of crops in the ground. 
         [0007]    Accordingly, a vertical tillage system has been developed incorporating fluted-concave disc blades, such as described in U.S. Publ. No. 2009/013388, the disclosure of which is incorporated herein. As described therein, the vertical tillage system utilizes a set of rolling basket assemblies supported by a frame that also carries the fluted-concave disc blades and that are designed to provide a downward force on the frame. The rolling basket assemblies include reels that are designed to rotate as the frame is pulled by a towing vehicle, e.g., tractor. As the reels rotate, they penetrate and preferably explode clumped soil and/or crop residue. 
         [0008]    The reels or rotating baskets are generally mounted to the frame through a rotational coupling that allows the reels to rotate as the frame is being towed. The rotational coupling typically includes a spindle that is cantilevered from the frame. In one known implementation, the spindle is weld to the frame. While generally effective in attaching the spindle to the frame, the weld joint, as well as the spindle itself, can fatigue over time. Moreover, it has been found that operating the tillage system at faster towing speeds during in-field use or transport, or with larger loads, can hasten the fatigue and ultimately the premature failure of the weld joints and the spindle. As farmers are increasingly demanding implements, such as vertical tillage systems, that can be towed through the field or transported at faster speeds and/or with greater loads, the additional strain and stresses placed on the cantilevered components, and the weld joints, must be addressed to reduce the premature failure of these components and, ultimately, the implement itself. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is directed to an apparatus for reducing the stresses placed on a cantilevered component mounted to a rigid frame. The inventors have found that additional stresses and strains placed on the cantilevered components, such as spindles, pivots, and shafts, associated with increased operating speeds and/or loads of the implement can be mitigated by cushioned bushings coupling the cantilevered components to the rigid frame. As the cantilevered component is loaded due to bending moments, the cushioned bushings flex and cushion the cantilevered component. The cantilevered component is retained within the bushing using hardware that allows the cantilevered component to float as needed to further reduce stresses and strains thereon. 
         [0010]    Therefore, in accordance with one aspect of the invention, a reel mounting assembly for use with a tillage implement is provided. The mounting assembly includes a mounting arm having an axially extending cylinder and configured to be coupled to a frame of the tillage implement. A cushioned bushing is retained within the cylinder. A spindle is coupled to the cushioned bushing and a reel is coupled to the spindle and configured to rotate about the spindle. The cushioned bushing is configured to flex when the spindle is loaded to reduce stress on the spindle. 
         [0011]    In accordance with another aspect of the invention, a tillage implement is provided and includes a frame having a tow bar adapted to be coupled to a prime mover and a mounting arm coupled to the frame. The implement further includes a reel adapted to pulverize crop residue present on a field surface and a spindle arrangement coupling the reel to the mounting arm. The spindle arrangement includes flexible components configured to flex when the spindle arrangement is loaded due to bending moments. 
         [0012]    According to a further aspect of the invention, an agricultural implement includes a frame configured to be towed by a towing vehicle and a member cantilevered from the frame. The invention provides a bushing interconnecting the member and the frame, and formed of cushioning material that is configured to flex and cushion the cantilevered member when the cantilevered member is loaded due to a bending moment. 
         [0013]    Other objects, features, aspects, 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 
         [0014]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout. 
           [0015]    In the drawings: 
           [0016]      FIG. 1  is an isometric view of a vertical tillage implement incorporating the present invention; 
           [0017]      FIG. 2  is a detailed isometric view of a portion of the vertical tillage implement shown in  FIG. 1 ; 
           [0018]      FIG. 3  is a section view of the vertical tillage implement taken along line  3 - 3  of  FIG. 2 ; 
           [0019]      FIG. 4  is a front isometric view of the rotational coupling of a rotating basket to a rigid frame member; and 
           [0020]      FIG. 5  is a side isometric view of that shown in  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    The present invention is directed to an apparatus to provide cushioning for a cantilevered component mounted to a rigid frame and will be described as being used with a vertical tillage implement, but it is understood that the invention could be used in other agricultural and non-agricultural applications. 
         [0022]    Referring to  FIG. 1 , a vertical tilling implement  10  is shown. An agricultural vehicle (not shown) pulls the vertical tilling implement  10  in a direction of motion A. The vertical tilling implement  10  includes a main frame  12 . The wing frame  12  has a hitch  14  on the front end that may be used to connect the vertical tilling implement  10  to an agricultural vehicle such as a tractor. Additionally, a set of wheels  16  are connected to the wing frame  12 . The set of wheels  16  are oriented in a direction that is in general alignment with the direction of motion A. The set of wheels  16  includes a set of center wheels  18  and a set of pivoting wheels  20 . The set of center wheels  18  is attached across the wing frame  12  at positions, for example, roughly midway between the front and rear ends of the wing frame  12 . The set of center wheels  18  may include a system for adjusting the distance between the main frame  12  and the set of center wheels  18 . This system for adjusting may permit the set of center wheels  18  to be statically fixed during the movement of the vertical tilling implement  10  or to be dynamically adjustable as the vertical tilling implement  10  travels. The set of pivoting wheels  20  are connected to the front distal ends of the wing frame  12 . As will be described, the set of pivoting wheels  20  may include at least two pivoting wheels that reduce the amount of lateral movement of vertical tilling implement  10  as it is pulled. 
         [0023]    The vertical tilling implement  10  also includes a plurality of rows of fluted-concave disc blades  22  attached to the main frame  12 . In accordance with one configuration, the plurality of rows of fluted-concave disc blades  22  is indexed. In particular, the plurality of rows of fluted-concave disc blades  22  includes a front left row  24 , a front right row  26 , a rear left row  28 , and a rear right row  30 . When indexed, the front left row  24  and the front right row  26  are aligned with the rear left row  28  and the rear right row  30  such that areas of ground between the blades in the front left rows  24  and the front right row  26  are engaged by the blades in the rear left row  28  and the rear right row  30  as the tilling implement is pulled forward. 
         [0024]    The fluted-concave disc blades will induce lateral and vertical forces in the vertical tilling implement  10 . The fluted-concave disc blades on the plurality of rows of fluted-concave disc blades  22  have surface features, as will be described below. The rotation of the fluted-concave disc blades and the engagement of the surface features of the blades will displace soil during the tilling operation. However, the engagement of the surface features of the blades with the soil will also apply a force to the blades. The blades engagement with the soil will displace the fluted-concave disc blades in a direction perpendicular to the blades direction of rotation. 
         [0025]    The front left row  24  is symmetric about a centerline  32  of the vertical tilling implement  10  with the front right row  26 . Likewise, the rear left row  28  is symmetric about the centerline  32  of the vertical tilling implement  10  with the rear right row  30 . Additionally, the front left row  24  is substantially symmetric about a line perpendicular to the direction of motion A with the rear left row  28 . Likewise, the front right row  26  is substantially symmetric about a line perpendicular to the direction of motion A with a rear right row  30 . These general symmetries may involve some of the rows being offset relative to the others to achieve the indexing of the blades as described above. 
         [0026]    When the plurality of rows of fluted-concave disc blades  22  are arranged in a symmetrical arrangement about the centerline  32 , such as illustrated in  FIG. 1 , a gap between each side of symmetrical rows may be created. A center tilling member  34  may be placed in this gap to ensure that all the soil passing under the vertical tilling implement  10  is tilled as the tilling implement is pulled forward. The center tilling member  34  may be a coulter, as shown in  FIG. 1 , another fluted disc blade, or the like. 
         [0027]    It should be observed that although  FIG. 1  only shows four rows included in the plurality of rows of fluted-concave disc blades  22 , there may be fewer or more rows of fluted-concave disc blades. Additionally, while the illustrated embodiment shows the plurality of rows of fluted-concave disc blades  22  having an x-shaped configuration based on the described symmetry, the plurality of rows of fluted-concave disc blades  22  may have a different configuration. For example, the plurality of rows of fluted-concave disc blades  22  may have a diamond configuration, a k-shaped configuration, or all may be parallel with each other in a direction perpendicular to the direction of motion A. Furthermore, it is contemplated that some or all of the rows may be configured in asymmetric arrangements. 
         [0028]    It should be further observed that the rows may be at oriented at angles of about  18  degrees from a direction perpendicular to the direction of pull. As described above, known tillage implements utilizing typical smooth concave blades would not operate properly under such an aggressive angle and achieve satisfactory results. Historically, flat blades mounted in rows at this aggressive of an angle would break as a result of the massive side pressure of the soil as the tillage implement was pulled and would tend to leave large clods of soil that require a second tilling pass. However, in the disclosed embodiments, the fluted blades are unexpectedly capable of one-pass tilling at this aggressive gang angle despite only having a shallow concavity. 
         [0029]    Rolling basket or reel assemblies  36  are connected to the rear end of the main frame  12  to provide downward pressure. Although  FIG. 1  shows three rolling basket assemblies  32 , two of which having rotational axes which are not collinear with the third, the rolling basket assemblies  32  may include fewer or more members providing downward force. 
         [0030]    Referring now to  FIG. 2 , a detailed view of the rear left row  28  and the rolling basket assemblies  36  are shown. The rolling basket assemblies  36  are connected to the main frame  12  by an adjustable pressure assembly  38 . The adjustable pressure assembly  38  includes a set of arms  40  extending rearwardly from the main frame  12  and downwardly to engage the rolling basket assemblies  36 . The set of arms  40  includes a pair of fixed beams  42  which have a set of spring connection points  44  positioned frontwardly on the fixed beams  42  and a set of links  46  that is hingedly connected to the fixed beams  42  near the midpoints of the fixed beams  42 . A set of springs  48  run between the set of spring connection points  44  and the set of links  46 . The set of links  46  also connect in the rearward direction to a set of L-shaped bars  50 . The set of L-shaped bars  50  are positionally adjustable but are also connected to and restricted in movement by a pair of slide bearings  52  located on the set of fixed beams  42  at a point near the rearward ends of the set of fixed beams  42 . 
         [0031]    The adjustable pressure assembly  38  applies a downward force on the rolling basket assemblies  36 . The set of springs  48  may be selected to apply a desired force on the set of links  46 . This force will cause the set of links  46  to rotate about their hinged connections to the fixed beams  42  such that the set of L-shaped bars  50  exert more or less downward force into the rolling basket assemblies  36 . 
         [0032]    The rolling basket assemblies  36  includes a frame  54  extending between the set of arms  50  and about the ends of a rolling basket  56 . To this end, the frame  54  engages the rolling basket  56  through a rotational coupling  58 , such that the rolling basket  56  is capable of rotating about a rotational axis  60 . Although multiple rolling basket assemblies  36  are not required, in the case where there are multiple rolling basket assemblies  36 , their respective rotational axes, as illustrated, may be non-collinear. However, it is contemplated that in some applications, it may be desirable for the rotational axes to be collinear. 
         [0033]    The rolling basket  56  is formed by a plurality of bars  62  that extend between end caps  64  and around a set of supporting framework rings  66 . The end caps  64  engage the rotational coupling  58  to allow the rolling basket assemblies  36  to rotate. As illustrated, it is contemplated that the plurality of bars  62  may have a helical configuration, such that the plurality of bars  62  twists around the cylindrical face of the rolling basket assemblies  36 . However, in some configurations, straight or other varied arrangements may be utilized. The plurality of bars  62  may have flat or rounded surfaces. In the illustrated configuration, the plurality of bars  62  has flat surfaces and a rectangular-shaped cross-section. Furthermore, the plurality of bars  62  are mounted between the end caps  64  such that the outermost edge of the diameter of the rolling basket assemblies  36  are the sharp corners of the plurality of bars  62 . As such, as the rolling basket assemblies  36  rotate, a sharp corner is designed to impact the ground surface and, thereby, penetrate, and preferably, explode, the clumped soil and/or residue. That is, as the soil passes under the rolling basket assemblies  36  the rolling basket  56  rotates and the edge of the plurality of bars  62  act to both crush the remaining large chunks of earth as well as to level the soil. 
         [0034]    A section view of the rotational coupling  58 , taken along line  3 - 3  of  FIG. 2 , is shown in  FIG. 3 . Corresponding isometric view of the rotational coupling  58  are shown in  FIGS. 4 and 5 . The rotation coupling  58 , as noted above, couples the basket  56  to the frame  12 . More particularly, the frame  12  includes an arm  67  that carries a rigid, generally cylindrical shaped member  68 . The rotational coupling  58  includes a spindle  70  that is coupled to the rigid member  68  by a pin  73 . As shown in  FIG. 3 , the spindle  70  is cantilevered from the arm  66  via the connection to the rigid member  68 . The spindle  70  carries a hub  74  to which a basket hub mount  76  (or end cap) is coupled by fasteners  78 ,  80 , such as bolts. The hub  74  is free to rotate around the spindle  70  by interfacing bearings  82 ,  84 . As such, the basket hub mount  76 , and thus basket  56 , may passively rotate around spindle  70  as the implement  10  is pulled along the field surface. Additionally, as shown in the figure, the hub  74  is carried by the spindle  70  such that a small gap  86  is present between the rigid member  68  and the hub  74 , which allows the hub mount  74  to rotate relative to the rigid member  68 . 
         [0035]    Bushings  88 ,  90  are interposed between the shaft of the spindle  70  and the inner surface of the rigid member  68 . The bearings are comprised of a composite material that flexes to provide cushioning for the spindle  70  when the spindle is loaded due to bending moments. Thus, when the basket  56  is being operated at higher speeds or increased loads, the spindle  70  will be cushioned by the bushings  88 ,  90  to reduce stress placed on the spindle during such operation. Additionally, as noted above, the spindle  70  is allowed to float relative to the frame  12 , which also reduces the stress that would otherwise be placed on the spindle during high speed and/or high load conditions. 
         [0036]    While the rotational coupling  58  for only one of the baskets  56  has been described in detail, it is understood that the other rotational couplings, such as the rotational coupling at the opposite end of the basket  56  is similarly constructed. Additionally, while the invention has been described with respect a cantilevered spindle for coupling a reel or a basket to an implement frame, the invention is not limited to such an application. 
         [0037]    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.