Levee plow with extensible linkage
DESCRIPTION 
     1. Background of Prior Art 
     Conventional means for constructing levees involves the use of bull-dozers and/or other earth moving equipment which is very expensive to own and operate and requires an undue amount of time for the actual construction. Some attempts have previously been made to construct levees through the use of disk or harrow plows, but here again, an undue amount of time, effort and expense has been involved because an excessive number of trips or passes over the field have been required and after a number of passes have been made, such implements tend to become relatively ineffective because they cease to effectively move the soil laterally to a higher grade or level. As a consequence, the building cost for levees has been excessive with respect to time, equipment, fuel, and money. 
     In addition, problems encountered in the use of disk or harrow plows have included difficulty in getting each gang to penetrate and move the soil to the same extent and the impossibility of adjusting such depth while the equipment is moving. As a consequence, much time is lost and much frustration as well as undesirable results have been experienced. My invention obviates these problems. 
     2. Brief Description of the Invention 
     I have provided a levee plow in which the harrow-gangs are mounted on a tubular frame which is extensible or contractible and thus can bring soil centrally from a wider than normal area. Hydraulic cylinders connected in series fluid-flow relation insures that the individual horrow-gangs are depressed to exactly the same extent, and permits vertical adjustment of some while in motion. Through the use of such cylinders, the outer ends of the gangs may be maintained in slightly elevated relation to inner end portions to cause the latter to more effectively initiate the construction of the levee, in the initial pass of the plow, by forming a narrow steep-sloped core. The cylinders make it possible to forcibly depress and maintain the outer end portions at an ever-increasing lower level as subsequent passes are made, to thereby more effectively move the soil to the center line of the levee being built. By forcibly holding the outer end portions in fixed depressed relation, the harrows are forced to cut through all contour irregularities of the soil and eliminate same. Fewer passes are required and a better and a steeper sloped levee is provided at reduced expense. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A detailed description of one preferred embodiment of the levee plow is hereafter described with specific reference being made to the drawings in which: 
     FIG. 1 is a top plan diagrammatic view of my new levee plow being drawn by a tractor; 
     FIG. 2 is a simplified rear elevational diagrammatical view of the plow only; 
     FIG. 3 is a perspective diagrammatical view of the plow on a larger scale as viewed from the rear; 
     FIG. 4 is a fragmentary perspective view of the transverse frame and its couplings for attachment to a conventional tractor three-way hitch; 
     FIG. 5 is a fragmentary perspective view from the rear of the threaded adjustment mechanism of the telescoping tubular frame which supports the harrow-gangs; and 
     FIG. 6 is a rear perspective diagrammatic view of my plow shown detached from the tractor and on parking stands. 
    
    
     DETAILED DESCRIPTION OF INVENTION 
     The preferred embodiment of my invention is shown in FIGS. 1-6 inclusive. As shown, it includes a levee plow indicated generally by the number 7 which is constructed and arranged to be drawn by a tractor 8. The tractor 8 has a conventional three point hitch 9 by means of which it is connected to the plow 7 through three couplings 10 which are provided for that purpose and are best shown in FIG. 6. These three couplings are carried by an elongated transverse rigid frame 11 by means of which the plow 7 is elevated and lowered between elevated non-operative and a non-engaging position and lowered, operative, engaging position with respect to the ground. 
     Pivotally mounted upon the frame 11 and extending parallel thereto is an extensible and contractable tubular frame 12 which includes a pair of telescoping tubular sections 13 and 14. As best shown in FIG. 6, this tubular frame 12 includes a pair of mounting plates 15 and 16 by means of which it is pivotally mounted on the frame 11. 
     Each pair of mounting plates 15 and 16 includes a pair of vertically spaced pivot plates such as indicated by the numerals 17, 18 and 19, 20. Pivot plates 19, 20 are pivotally connected to the frame 11 by pivot pin 21 which extends therethrough and is received in pivot bearing 22 provided for that purpose on frame 11. Tubular pin 23 pivotally connects the outer end of the tubular section 14 to pivot plates 19 and 20 and pivot pin 24 pivotally mounts mounting bracket 25 upon the rear end of the pivot plates 19 and 20. This can best be seen in FIG. 6. 
     Similarly, pivot pin 26 pivotally mounts pivot plates 17 and 18 upon frame 11 and extends through pivot bearing 27. Pivot pin 28 extends through each of the plates and the outer end of tubular section 13 and pivot pin 29 pivotally connects the rear end of the two plates to mounting bracket 30, all as shown in FIG. 6. 
     Each of the mounting brackets 25 and 30 includes a pair of vertically spaced inwardly extending plates such as indicated by the numerals 31 and 32. Each also includes an upwardly and outwardly extending support arm 33 and a pair of depending mounting ears 34,35. Each of said brackets pivots about its respective pivot pin 24, 29. Each of the brackets have been numbered accordingly. 
     Each of said brackets 25 and 30 pivotally support a gang disk harrow such as indicated generally by the numeral 40. Each of said harrows is pivotally mounted on the pair of ears 34 and 35, as best shown in FIG. 3, for vertical movement about a horizontal pivot pin 41 which extends through the frame 42 of the gang at a point a substantial distance inwardly of the inner end of the frame. 
     The inner end of a cylinder such as indicated by the numeral 44 is pivotally mounted on the outer end of each of the support arms 33 by means of pin 45. Rod end 46 of the cylinder carries a yoke 47 and a pin 48 by means of which it is connected to the extreme outer end of the gang frame 42. This can best be seen in FIG. 3. 
     Each of the cylinders 44 is a double acting rephasing cylinder and is connected in series fluid-power relation by hydraulic tubes 49, as shown in FIG. 6. Thus, when the cylinders are to be extended, fluid is caused to enter the head of one of the cylinders, as shown at the right in FIG. 6, which causes the fluid at the opposite and outer end to be conveyed by one of the tubes 49 to the head of the other cylinder. The oil at the outer end of the receiving cylinder is returned to the reservoir of the tractor, the hydraulic power take-off of which is connected to the tubes 49 and the power controls of which are utilized to control the flow of hydraulic fluid through the hoses 49. Of course, when the cylinders are to be contracted, the direction of flow is reversed. This series-flow connection assures that the same pressure will be applied by each of the cylinders 44 and consequently there is an equal extension of the cylinder rods and the same downward pressure is applied to each of the opposed gangs. It will be noted that each of the gangs is constructed and arranged so as to move the soil laterally toward the center line of the levee to be constructed as illustrated in FIG. 2. 
     A threaded mechanism 50, similar in construction to a turnbuckle, is pivotally connected to the telescoping sections 13 and 14 of the tubular frame 12. As best shown in FIG. 6, this mechanism 50 includes a pair of externally threaded shafts 51 and 52 which are pivotally connected by pins 53, 54 to a pair of pivot ears 55 and 56, one each of which is carried by one of the tubular sections. An internally threaded tube 57 threadedly receives the two shafts 51, 52 and is turned thereabout by means of a crank rod 58. The two threaded shafts 51 and 52 are oppositely threaded so that rotation of the tube 57 by means of the crank 58 will cause the tubular frame to extend or contract, depending upon the direction of rotation of the tube 57. 
     As shown in FIGS. 1, 2 and 6 the outer end of each of the harrow-gangs 42 is connected by an adjustable link 59 to the frame 11 by depending straps 60 and a pin 61. 
     It will be readily seen that my levee plow can be readily moved between ground-engaging operative position and non-engaging non-operative position by the tractor 8 through manipulation of its 3 point hitch 9, as is conventional. However, my levee plow makes it possible to utilize the disk harrows 40 in a more effective manner, for during the initial pass of the tractor along the center line of the levee to be built, the outer end portion of the two gang harrows 40 can be elevated by manipulation of the cylinders 44 relative to its inner end, thereby causing the innermore individual disks of the two harrows to operate more effectively on the soil immediately adjacent the center line. On the second pass over the center line, the cylinders 44 are extended so that the outer end portions of each are forcibly held at an elevation below the inner portion of the gang, thereby more effectively moving the soil laterally to the centerline. If needed, depending upon the desired height of the levee, additional passes may be made over the centerline with the cylinders 40 further extended and forcibly held at a still lower elevation with each succeeding pass, thereby producing a very narrow base levee with steep side slopes in a minimum amount of time and with a minimum expenditure of fuel. 
     It should be noted that through the use of a series fluid power connection, each of the outer ends of the gangs 40 are forcibly held in a depressed position in the second and subsequent passes by the same pressure and to the same extent. If an uneven contour of soil is encountered, that uneven contour will be reduced and eliminated as a result of the unyielding corresponding and same positions at which these gangs are held. Of equal importance, is the fact that through the use of hydraulic cylinders and series fluid-power connections, the elevation of the outer end of the disk harrows can be changed while the tractor is in motion, with complete assurance that the adjustments made will be equal with respect to each of the harrows. This is not possible with equipment heretofore known. Such adjustments make it possible to save a substantial amount of time when such changes are required. It also makes it possible to be assured that the extent of adjustment is always equal. Since the adjustment is unyielding, the net resulting effects are the same. As a consequence, a better, more even, levee is produced which, of course, is highly desirable particularly when grains such as rice is to be planted and grown on the levee itself. 
     If a broader levee is desired, it is possible to produce such a levee with my levee plow by simply extending the tubular frame 12. This can be accomplished by rotation of the tube 57 through the use of the crank 58 so as to cause the tubular frame to extend. Extension of the frame 12 obviously causes the pivot pins 23 and 28 to be moved outwardly away from each other, thereby causing pivot plates 19, 20 and 17, 18 to swing outwardly about the axis of their pivot pins 21, 26 by means of which they are mounted on the frame 11. This causes each of the mounting brackets 25 and 30 to be swung outwardly and to correspondly move the two harrow-gangs 40 outwardly away from each other. Thus, with a single piece of equipment, and with minor adjustments thereto it is now possible to build levees of different widths and of different slopes as desired, thereby effectuating substantial savings in capital outlay for equipment and in time and expense involved in producing same. 
     The cylinders 44 are preferably of the type described in U.S. Pat. No. 3,666,284 but may be of the type described in the other U.S. Patents identified therein with respect to cylinder construction. Since they are connected in series, they differ somewhat in size so as to compensate for the differences in effectual cross-sectional areas of the rod side and the anchored end side of the pistons to thereby insure equal movement of the pistons. The cylinders 44 also preferably include the fluid by-passes and adjustable abutments for extension as described and shown in U.S. Pat. No. 3,666,284. 
     In considering this invention it should be remembered that the present disclosure is illustrative only and the scope of the invention should be determined by the appended claims.