Abstract:
An implement supports several ground cultivating tools on a main toolbar and at least one wing toolbar. The two are coupled together by two pivot brackets attached to the outer end of the main toolbar and the inner end of the wing toolbar. The pivot brackets are coupled to the main toolbar and the wing toolbar to permit the wing toolbar to pivot upwardly and downwardly with respect to the main toolbar. When the wing toolbar pivots upwards with respect to the main toolbar, it pivots about an upper point or axis and when it pivots downwards with respect to the main toolbar it pivots about a lower point or axis below the upper point or axis.

Description:
FIELD OF THE INVENTION 
     This application claims the benefit of U.S. Provisional Application No. 60/113,490, filed Dec. 22, 1998, and is an application for patent which relates to implements or agricultural implements. More particularly it relates to agricultural implements formed in several sections and joined by flexible couplings. 
    
    
     BACKGROUND OF THE INVENTION 
     With the increasing horsepower of modern tractors and the constant pressures of agricultural efficiencies, agricultural implements such as plows, rakes, harrows, disks, planters and the like have been increasing in their lateral dimensions. With the increased horsepower of the pulling implement of the tractor, more rows in a field can be cultivated simultaneously. Unfortunately, agricultural fields are uneven. As the implements increase in their lateral dimensions they do not follow the changing contours of the ground as accurately, leading to over- or under-penetration by ground-cultivating devices attached to the implement. For this reason in recent years the implements have been designed in several sections disposed along a line perpendicular to the direction of travel and connected to each other through generally flexible couplings disposed between the sections. The flexible couplings allow small upward or downward deflections between the sections of the implement as it travels over the ground, thus permitting each section to follow the contours of the field more accurately, and providing more even ground penetration by the attached devices. 
     There has been a trend in recent years to plant crops in rows spaced ever more closely together. As a result, each of the ground-cultivating devices such as row units for planting seed are spaced closer together on each section of the implement&#39;s tool bar. Given row spacings of fifteen inches, for example, the row units on a planter would be spaced fifteen inches apart, thereby providing a gap of only one to two inches between adjacent row units on adjacent sections of the tool bar. If such a coupling is used, there is a real danger that as one section of the tool bar is flexed upward or downward over a ground contour that it will cause adjacent row units to contact each other and break. What is needed, therefore, is an improved agricultural implement that will permit greater relative motion between adjacent sections of the implement while reducing the risk of damaging ground cultivating devices, such as row units, mounted on those sections. It is an object of this invention to provide such an implement 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows an implement&#39;s row units coupled thereto where the two tool bars are coupled together using a high mobility flexible coupling in accordance with the present invention; 
     FIG. 2 illustrates the main tool bar, the wing tool bar and the coupling with the row units removed for clarity; 
     FIG. 3 illustrates the arrangement of FIG. 1 where the wing tool bar is pivoted upward with respect to the main tool bar due to changes in ground contours; 
     FIG. 4 shows the arrangement of FIG. 2 with the wing tool bar pivoted upwards; 
     FIG. 5 shows the arrangement of FIG. 1 with the wing tool bar pivoted downwards due to changes in ground contour; 
     FIG. 6 illustrates the tool bars and coupling of FIG. 5 with the row units removed for clarity; 
     FIG. 7 is a top view of an agricultural implement drawn by a tractor and having several laterally disposed sections that are jointed by flexible couplings; 
     FIG. 8 illustrates a prior art flexible coupling joining two adjacent tool bars; 
     FIG. 9 is an exploded view of the high mobility flexible coupling. 
    
    
     Before explaining at least one embodiment of the invention in detail it is to be understood that the invention is not limited in its application to the details of 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 or being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 7, a tractor  10  is shown towing an implement  12  that is comprised of three tool bars, a main tool bar  14  and two wing tool bars  16  and  18  that are coupled to the main tool bar via flexible couplings  20  and  22 , respectively. Several row units  24  (exemplary of the wide variety of ground cultivating devices that could be attached to the sections of an implement) are mounted on each of the tool bars. These row units are aligned on fifteen inch centers across the width of the three tool bars to thereby define several equally spaced rows  26  that are cultivated in the field. These row units typically have a width of ten to fourteen inches, thereby typically providing a gap  28  between each adjacent pair of row units of one and three inches. 
     Prior art flexible couplings  20 ,  22  have been made with a single pivot point  30  as shown in FIG.  8 . This pivot point  30  was typically defined by a steel pin passing through holes in the ends of the tool bars to permit slight upward or downward pivoting of the wing tool bars  16 ,  18  with respect to the main tool bar  14 . Due to their fixed pivot position, they permit adjacent row units (not shown) mounted on either side of the pivot  30  to collide when wing tool bar  18  is moved upward or downward with respect to main tool bar  14 . Leading links  32  and  34  are coupled to wing tool bar  16  and  18 , respectively, and to tongue  36  of implement  12  to prevent the wing tool bars from being bent backwards as the implement is towed through the field. 
     FIG. 9 shows a high mobility flexible coupling  22 ′ for joining the ends of main tool bar  14  and wing tool bar  18  that improves upon the prior art coupling of FIG. 8 by providing a plurality of pivot points. This coupling includes elongate members  38  and  40  extending upward from tool bar  14  and elongate members  42  and  44  extending downward from wing tool bar  18 . Elongate members  38  and  40  have holes through an upper portion that define and support pin  46  and elongate members  42  and  44  have holes to a lower end thereof that define pin supports for pin  48 . An elongate link  50  extending approximately perpendicularly to the longitudinal extent of main tool bar  14  and wing tool bar  18  is disposed between main tool bar  14  and wing tool bar  18  and is coupled to the elongate members. Pin  46  passes through elongate members  38  and  40  and through a hole in the upper end of link  50  to define a pivotal relationship between link  50  and main tool bar  14 . The axis of relative rotation defined by this pivot is substantially horizontal. Pin  48  similarity passes through the holes in the lower ends of elongate members  42  and  44  and through a hole in a lower end of link  50  to define a pivotal relationship between the lower end of link  50  and wing tool bar  18 . The axis of relative rotation defined by this pivot is substantially horizontal. Recesses  52  and  54  are provided between elongate members  42  and  44  and  38  and  40  on the ends of tool bars  18  and  14 , respectively, to support the sides of link  50  which is sized to fit into these recesses when main tool bar  14  and wing tool bar  18  are substantially parallel. FIGS. 2,  4  and  6  show that the assembly pivots about a top and a bottom pivot point when wing tool bar  18  is pivoted upward or downward with respect to the main tool bar  14 . 
     FIGS. 1,  3  and  5  illustrate a rear view of implement  12  in the vicinity of the flexible coupling  22 ′ (as shown in FIG. 7) and show a portion of main tool bar  14 , wing tool bar  18  and two row units  24 , one mounted on each of main tool bar  14  and wing tool bar  18 . In FIG. 1, the position of the flexible coupling is shown when main tool bar  14  and wing tool bar  18  are parallel and colinear. FIG. 2 shows the relative positions of main tool bar  14  and wing tool bar  18  when an outer end of wing tool bar  18  is pivoted upward with respect to main tool bar  14 . FIG. 5 illustrates the relative positions of main tool bar  14  and wing tool bar  18  when an outer end of wing tool bar  18  is pivoted downward with respect to main tool bar  14 . As can be seen in these three views, when wing tool bar  18  is pivoted upward with respect to main tool bar  14  (FIG. 3) the two tool bars pivot with respect to each other around a top pivot. By pivoting relative to each other about a top pivot point disposed above the center line of main tool bar  14  and wing tool bar  18 , wing tool bar  18  can rise higher in the air, and be disposed at a greater upward angle with respect to main tool bar  14  without causing contact between the two adjacent row units  24  as compared to the prior art pivot of FIG.  8 . In a similar manner, FIG. 5 shows that wing tool bar  18  pivots with respect to main tool bar  14  a pivot point below the top pivot point when an outer end of wing tool bar  18  is lowered. By pivoting with respect to each other about a pivot point disposed below the top pivot point, wing tool bar can rotate downwardly with respect to main tool bar  14  without causing interference or contact between the two adjacent row units  24  to a greater extend than provided by the prior art flexible coupling of FIG.  8 . In this manner, a high mobility agricultural implement employing high mobility flexible coupling  22 ′ provides superior performance and ground contour following ability than an implement equipped with the coupling of FIG.  8 . 
     The flexible coupling of FIGS. 1-6 and  9  can be used in implement  12  in place of couplings  20  and  22 , instead of the prior art coupling shown in FIG.  8 . The example described above shows upwardly extending members from tool bar  14  and downwardly extending members from the wing tool bar connected to it. The coupling could as easily be made with downwardly extending members from main tool bar  14  and upwardly extending members from the wing tool bar to which it is connected. The spacing of the row units is not critical. While the benefits of the flexible coupling are most clear when the row units  24  are spaced on fifteen inch centers, nonetheless, the same benefits can be provided when the row units are spaced farther apart, for example, on twenty to thirty inch centers. 
     The description above was directed to “row units.” Nonetheless, the high mobility flexible coupling described herein is of similar benefit for any implement having different ground cultivating devices coupled to its flexibly coupled sections. For example, disks, rakes, harrows, chemical applicators or other tool bar mounted devices could be substituted for the row units illustrated in the figures. 
     Thus, it should be apparent that there has been provided in accordance with the present invention a high mobility agricultural implement that fully satisfies the objectives and advantages set forth above. Although the invention has been described in conjunction with specific embodiments thereof, it is evidence that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.