Abstract:
An agricultural implement includes first and second outer harrows positioned adjacent front and left sides and front and right sides of a frame, respectively, at generally opposite diagonal directions. Third and fourth harrows are similarly positioned adjacent rear and left sides and rear and right sides of the frame, respectively, at generally opposite diagonal directions. The implement may include inner harrows positioned to close gaps left by the outer harrows and positioned at generally opposite diagonal configurations. Each harrow includes a plurality of discs and a chain with a plurality of links that are rotatable about the longitudinal direction of the chain so as to affect multi-purpose actioning of the soil by being able to level the surface rather than dragging material while also breaking up or uprooting weeds or stubble. Left and right sides of the frame are foldable upwardly and inwardly for transport and storage.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates generally to agricultural equipment and, more particularly, to an agricultural implement that does not merely clear away material on top of a ground surface but rather is able to furrow the soil, break up the material so it can be incorporated into the ground or decomposed. The agricultural implement also provides for the leveling of the soil and uprooting of weeds. 
   Farmed land by its nature undergoes cyclic periods of sowing, growth, and harvest. Sowing, growing and harvesting of crops all require the certain conditioning of the soil if successful returns are going to be obtained from the worked area. Conditions left over a farmed area particularly after harvest do not normally provide the ideal conditions in which further crops can be sowed. When the main crop is harvested the soil often includes weeds that need to be destroyed as well as stubble and the like from previous crops requiring uprooting and cutting before any seed can be sowed. 
   Not only does stubble require uprooting or cutting and weeds still need to be killed off, but there is also the further requirement of having the soil leveled such that sowing implements responsible for reintroducing a new crop into the field can do so efficiently and expeditiously. 
   Though in the past various agricultural implements have been provided that attempt to address certain of the above referenced ground engaging problems associated with uprooting or cutting of stubble, killing of weeds and also leveling, as to date there is yet to be provided one multi purpose simple structural agricultural piece of apparatus that can achieve all these objectives when engaging a ground surface. Further, existing proposals may even lead to an exaggeration of some of the problems also discussed above. 
   For example, a Russian patent referred to as SU1523061 discloses a heavy chain having a sequence of interconnected links that may be pulled along by a tractor or the like. The chain is able to pick up any debris, stubble or other material left on the surface and as it works its way across a field, it essentially drags this material like a rake, and slowly levels out the ground left behind. A problem with this construction is that as the chain has no special characteristics other than simply being interconnected links with no set rotation or the like, the chain simply operates like one large heavy broom or rake which would carry the material along in a sweeping action rather than have the material settle in situ as part of the leveling process. 
   The chain in this Russian invention has no capabilities of killing weeds that remain on the surface nor can it effectively uproot or cut stubble and leave such material in place. As explained above, rather than simply uprooting or cutting the stubble left on the surface, the chain would pull and sweep this material away from the location from where it was originally derived from. Hence, the swept away material has no opportunity to decompose and return to the soil. At best the agricultural implement was adapted to ground engage in SU1523061 for a raking effect of the ground by virtue of blades or spikes that preceded the chain, and thereafter a flattening or sweeping effect was provided for by the chain. The mere raking of material on the land being tillaged is undesirable as it removes important nutrient derivable from the stubble and the like and also exposes fresh soil to wind erosion and the like. 
   There have been further proposal whereby chains have been used to address some of the problems discussed above, but again each of these agricultural implements, in seeking to solve the problem of one aspect, tend to exaggerate problems associated with the other aspects. For example, U.S. Pat. No. 4,893,682 provides for an agricultural implement in which a rotating flexible chain can assist in soil erosion control. Nonetheless, the intended purpose of the invention is simply to slow down erosion by controlling water movement, which is done by the creation of dimples or miniature dams or the like across the ground surface as the chain is passed there along. The creation of these dimple features results from the unique baffles or blades that extend out from longitudinal links. Though the chain is being pulled along by a tractor or the like, it still does not have a multi-purpose function that is able to provide ground leveling, weed control and stubble break up substantially in situ. As with the chain provided for in the Russian document referred to above, all this chain does is provide a raking effect. 
   Although the devices proposed by SU745395 and SU982551 are potentially able to provide some ground leveling effect, there is no mechanism to break up stubble, nor is there the ability to control the weed, by cutting up the weeds with the action of some further structural feature. 
   Therefore, it would be desirable to have an agricultural device that does not just clear away material from the top of a ground surface, but rather breaks up the material and furrows the ground so that the broken up material may be incorporated into the soil or decomposed. Further, it would be desirable to have an agricultural implement that levels a ground surface, does not allow its chain harrows to become high centered, and which includes auxiliary and redundant harrows for efficient and complete breaking up and harrowing of surface materials and soil. 
   SUMMARY OF THE INVENTION 
   Accordingly, an agricultural implement according to the present invention includes a frame having a front end, a rear end, a left side, a right side, and a plurality of tires. Further, the implement includes a plurality of harrow members, each harrow member having plurality of discs and a chain with a plurality of links. The discs are coupled to the links and extend generally outwardly therefrom. A first harrow is operatively coupled to the frame generally adjacent to the front end and said left side, wherein the first harrow member extends in a first diagonal direction. A second harrow member is operatively coupled to the frame generally adjacent the front end and right side, wherein the second harrow member extends in a second diagonal direction. A third harrow member is operatively coupled to the frame generally adjacent the left side and the rear end, wherein the third harrow member also extends in the second diagonal direction. A fourth harrow member is operatively coupled to the frame generally adjacent the right side and the rear end, wherein the fourth harrow member extends in the first diagonal direction. Additional harrow members may be positioned to the interior of the harrows disclosed above and may be situated at opposing diagonal configurations. 
   Each chain has a front end and a rear end with each chain front end being relatively forward of the chain rear end. Further, each disc has a concave side facing a respective chain front end and a convex side facing a respective chain rear end. The first, second, third, and fourth harrows are outer harrow members. Each outer harrow member chain has an end coupled to a tensioning assembly such that the harrow member remains flexible to conform to a ground surface but with tension not to either bottom out in low areas or to glide over high areas without digging in. 
   It is important that the concave portions of the discs generally face forward. This facilitates a greater ability to engage the soil and to furrow the soil. In essence, this orientation may actually contribute to a sharpening of the leading edge of the disc so as to allow it to more effectively cut and uproot weeds and improves the effect of mulching the stubble. In addition, the forward orientation of the concave portions more effectively turns the soil for creating a greater ability to level uneven fields. The greater movement of soil is also beneficial when using the harrow to incorporate beneficial seeds, manures, and fertilizers into the soil. 
   The agricultural implement also includes a pair of offset rear wheels that inhibit the harrow members from becoming high centered when one portion of the implement is situated over a low area, e.g. a water furrow, while another portion is over a high area. More particularly, the offset wheels assist in keeping the entire implement properly positioned over a ground surface while being dragged over uneven portions of a field. 
   Therefore, a general object of this invention is to provide an agricultural implement for breaking up the ground, furrowing it, and depositing the broken up material back into the ground. 
   Another object of this invention is to provide an agricultural implement, as aforesaid, that levels the ground by maintaining its flexible chain harrows in tension. 
   Still another object of this invention is to provide an agricultural implement, as aforesaid, that includes multiple chain harrows in diagonal configurations for breaking up soil and other material. 
   Yet another object of this invention is to provide an agricultural implement, as aforesaid, that keeps its chain harrows from becoming high centered. 
   A further object of this invention is to provide an agricultural implement, as aforesaid, in which its plurality of concave discs and chain links enable material to pass through rather than being dragged along. 
   A still further object of this invention is to provide an agricultural implement, as aforesaid, having chain and disc links that are rotatable about the longitudinal direction of the chain so as to effect multi-purpose actioning of the soil by being able to level the surface rather than dragging material while also breaking up or uprooting weeds or stubble. 
   Still another object of this invention is to provide an agricultural implement, as aforesaid, in which the main framework includes left and right folding members that may be folded both upwardly and inwardly for transport and storage. 
   Other objects and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, embodiments of this invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an agricultural implement according to a preferred embodiment of the present invention; 
       FIG. 2  is an isolated view on an enlarged scale taken from a portion of  FIG. 1 ; 
       FIG. 3  is an isolated view on an enlarged scale of the offset wheels as shown in  FIG. 1 ; 
       FIG. 4   a  is a top view of a chain harrow member removed from the agricultural implement as in  FIG. 1 ; 
       FIG. 4   b  is an isolated view on an enlarged scale taken from a portion of the harrow member of  FIG. 4   a;    
       FIG. 5   a  is a perspective view of the agricultural implement on a reduced scale as in  FIG. 1  with the side members in an unfolded configuration; 
       FIG. 5   b  is a perspective view of the agricultural implement as in  FIG. 5   a  with the side members in an upwardly folded configuration; 
       FIG. 5   c  is a perspective view of the agricultural implement as in  FIG. 5   a  with the side members in an upwardly and inwardly folded configuration; 
       FIG. 6  is a perspective view of a disc removed from a harrow member wherein the link is an open link; 
       FIG. 7  is a perspective view of a disc removed from a harrow member, wherein the link is a closed link; 
       FIG. 8  is a cross sectional view of the disc as in  FIG. 6  showing the disc and link with an integrated construction; 
       FIG. 9  is a side view of a portion of a harrow member as in  FIG. 4   b;    
       FIG. 10  is a cross sectional view of the disc as in  FIG. 6  showing the disc and link with a separated construction 
       FIG. 11  is an exploded view of the disc as in  FIG. 6 ; and 
       FIG. 12  is another perspective view of a chain harrow member. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An agricultural implement  100  (also referred to herein as a “harrow device”) according to the present invention will now be described in detail with reference to  FIGS. 1 through 12  of the accompanying drawings. More particularly, an agricultural implement  100  according to the current invention includes a frame  110  and a plurality of harrow members  120 . 
   The frame  110  has a front end  112   a , a rear end  112   b , a left side  112   c , and a right side  112   d . As shown in  FIGS. 5   a  through  5   c , a first folding member  113  may define the left side  112   c , and a second folding member  114  may define the right side  112   d . The folding members  113 ,  114  may selectively fold upwardly ( FIG. 5   b ) relative to a remainder  111  of the frame  110  and inwardly ( FIG. 5   c ) relative to the remainder  111  of the frame  110 . Similarly, a folding member  115  may define the rear end  112   b , and the folding member  115  may selectively fold upwardly ( FIG. 5   c ) relative to the remainder  111  of the frame  110 . The folding described above may allow the frame  110  to travel on a roadway or in other areas having restricted widths and/or lengths. 
   The frame  110  may further include a plurality of tires  116 . Two of the tires  116  may be coupled to the frame  110  in a generally central location  116   a  and may be generally coaxial ( FIG. 1 ), and two of the tires  116  may be coupled to the frame  110  in a generally rearward location  116   b  and have offset axes ( FIGS. 1 and 3 ). The offset axes of the tires  116  at the rearward location  116   b  may help keep the frame  110  from high-centering (or “bottoming out”) when passing over a water furrow in a field or other similar obstacles, as one of the wheels  116  may remain on a higher side of the furrow even when the other does not. 
   Each harrow member  120  may include a plurality of discs  122  and a chain  124  with a plurality of links  125 . As shown in  FIGS. 4   a ,  4   b , and  6  through  12 , the discs  122  may be coupled to the links  125  and extend generally outwardly therefrom. Each chain  124  may have a front end  124   a  and a rear end  124   b , each disc  122  may have a concave side  122   b  facing a respective chain front end  124   a , and each disc  122  may have a convex side  122   a  facing a respective chain rear end  124   b  ( FIGS. 4   a ,  8 ,  9 ,  10 , and  12 ). The links  125  are preferably movable relative to one another and may be closed links  125   a , such as links typically used in chains ( FIGS. 4   a ,  4   b , and  12 ), or the links  125  may be open links  125   b  with hook and loop portions  126   a ,  126   b  ( FIGS. 6 through 11 ). The discs  122  may be coupled to every link  125  ( FIGS. 4   a  and  4   b ), to approximately every second link  125  ( FIG. 12 ), or otherwise as appropriate. If open links  125   b  are used, the hook portions  126   a  may be configured to receive a respective loop portion  126   b  of another link  125 , and the loop portions  126   b  may be configured to receive a respective hook portion  126   a  of another link  125  ( FIG. 9 ). In addition, the hook and loop portions  126   a ,  126   b  may be selectively separable, as shown in  FIGS. 10 and 11 . In other words, the hook and loop portions  126   a ,  126   b  may be screwed together or otherwise fastened to form loops  125 . 
   Returning to  FIG. 1 , a first harrow member  120  (labeled  120   a  in  FIG. 1 ) may be operatively coupled to the frame  110  generally adjacent the front end  112   a  and the left side  112   c  so that the first harrow member  120   a  extends in a first diagonal direction. A second harrow member  120  (labeled  120   b  in  FIG. 1 ) may be operatively coupled to the frame  110  generally adjacent the front end  112   a  and the right side  112   d  so that the second harrow member  120   b  extends in a second diagonal direction generally opposite the diagonal direction of the first harrow member  120   a . A third harrow member  120  (labeled  120   c  in FIG.  1 ) may be operatively coupled to the frame  110  generally adjacent the left side  112   c  and the rear end  112   b  so that the third harrow member  120   c  extends in generally the same diagonal direction as the second harrow member  120   b . A fourth harrow member  120  (labeled  120   d  in  FIG. 1 ) may be operatively coupled to the frame  110  generally adjacent the right side  112   d  and the rear end  112   b  so that the fourth harrow member  120   d  extends in generally the same diagonal direction as the first harrow member  120   a.    
   The first and second harrow members  120   a ,  120   b  may be spaced apart adjacent the front end  112   a , and the third and fourth harrow members  120   c ,  120   d  may be spaced apart adjacent the rear end  112   b . To ensure that all ground surfaces passing underneath the frame  110  contact at least two harrow members  120  extending in opposite diagonal directions, fifth and sixth harrow members  120  (labeled  120   e ,  120   f  in  FIG. 1 ) may be included. The fifth harrow member  120   e  may be operatively coupled to the frame  110  so that it extends in a diagonal direction over a space having a width that is as large as the space between the first and second harrow members  120   a ,  120   b  at the front end  112   a  and as large as the space between the third and fourth harrow members  120   c ,  120   d  at the rear end  112   b . Similarly, the sixth harrow member  120   f  may be operatively coupled to the frame  110  so that it extends in a diagonal direction over a space having a width that is as large as the space between the first and second harrow members  120   a ,  120   b  at the front end  112   a  and as large as the space between the third and fourth harrow members  120   c ,  120   d  at the rear end  112   b . The diagonal direction of the sixth harrow member  120   f  may be opposite the diagonal direction of the fifth harrow member  120   e.    
   For each harrow member chain  124 , the front end  124   a  may be relatively forward of the rear end  124   b  so that the concave sides  122   b  of the discs  122  face forward (toward the frame front end  112   a ). As best shown in  FIG. 2 , the chain  124  of each outer harrow member  120  (i.e., the first, second, third, and fourth harrow members  120   a ,  120   b ,  120   c ,  120   d ) may have an end  124   a ,  124   b  coupled to a tensioning assembly  130 . Each tensioning assembly  130  may have a generally vertical shaft  132  passing through the frame  110 . The shaft  132  may have upper and lower arms  134   a ,  134   b  that extend outwardly. The upper arm  134   a  may be coupled to the frame  110  by a spring  135 , and the lower arm  134   b  may be coupled to a respective chain end  124   a ,  124   b . A bearing  136  may couple each lower arm  134   b  to the respective chain end  124   a ,  124   b  to allow the chain ends  124   a ,  124   b  to rotate relative to the lower arms  134   b.    
   In use, the frame  110  may be pulled across a ground surface (e.g., a field used for farming) by a tractor or another appropriate pulling device. The harrow members  120  may act to level the ground surface and additionally break up the ground surface without dragging and removing all of the top soil. More particularly, the links  125  of the chains  124  may rotate as they interact with the ground surface, causing the discs  122  to rotate and cut through the ground surface. The arrangement of the concave discs  122  may allow parts of the ground surface to pass through the chains  124  rather than simply being dragged along, as typically results when conventional chains are pulled across a ground surface. 
   By positioning the harrow members  120  as described above, two separate harrow members  120  may pass in opposite directions over every part of the ground surface under the frame  110 , aiding the leveling and cutting effect of the harrow members  120 . The bearings  136  may allow the chains  124  to rotate relative to the frame  110 , and the tensioning assemblies  130  may keep the chains  124  in relative tension so that the chains  124  do not get forced too high over high spots of the ground surface or too low in low spots of the ground surface. In other words, the tensioning assemblies  130  may ensure that the harrow members  120  dig into the ground surface only when appropriate. To allow the agricultural implement  100  to travel on a roadway or in other areas having restricted widths and/or lengths, the folding members  113 ,  114 ,  115  may be folded as described above. Some or all of the harrow members  120  may or may not have to be removed from the frame  110  for the folding members  113 ,  114 ,  115  to be folded. 
   It is understood that while certain forms of this invention have been illustrated and described, it is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof.