Abstract:
A lift device is mounted on a wheeled implement such as a disc harrow which has retractable wheels for transport. The lift device includes a pair of arms mounted on a horizontal pivot bar which is rotated by activation of the mechanism for lowering the wheels of the disc harrow. The arms hold a drawbar for a drag harrow when the drag harrow is to be transported and allow the drag harrow to hang vertically behind the disc harrow. In the suspended position, pivots in the arms allow the drag harrow considerable lateral freedom. When the arms are lowered, the drag harrow is released from the arms and dragged by pull lines. Hinges in the arms permit the arms to be folded up onto the disc harrow.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a device for transporting a piece of farm equipment, such as a drag harrow, which is pulled behind another piece of farm equipment, such as a disc harrow, having retractable wheels for transporting it. 
     In the preparation of soil for planting, a discing operation is frequently followed by breaking up clods, pulverizing the soil, and leveling the soil with a drag harrow. To avoid the necessity of carrying out two separate operations, the drag harrow may be pulled behind the disc harrow. This arrangement does an excellent job of preparing the soil. When the tandem implements must be moved from a field, however, difficulties arise. Disc harrows are generally provided with retractable wheels, powered by an hydraulic cylinder, which control the depth of the disc blades. Fully lowering the wheels raises the disc blades above the ground and permits the disc harrow to be transported. Traditionally, the drag harrow is disassembled and its individual sections are inverted and lifted onto the top of the disc harrow for transport. Alternatively, the drag harrow is left in the field and later transported separately. Neither approach is very satisfactory. The drag harrow sections are heavy and awkward to handle. For example, a 15 foot disc harrow may require a drag harrow having a central section about 5 feet wide and two outer sections each 6 feet wide, all connected to a 17 foot drawbar. Since each section is approximately square and weighs about 100 pounds, lifting the sections for transport is a difficult and time-consuming job. 
     Attempts have been made to design a drag harrow which may easily be transported with a disc harrow. Such devices are shown, for example, in U.S. Pat. Nos. 3,090,447 and 3,090,448 to Hotchkiss, Jr.. In these prior art systems, however, the drag harrow has been limited in length, width and type of construction, and the drag harrow of such systems has thus been less effective than the usual drag harrow. The combination of the two harrows is also less maneuverable than the usual tandem disc harrow and drag harrow. Just as important, the combination is difficult to transport because of the length, width and rigidity of the combined structure, particularly when gates have been built only large enough to accommodate the disc harrow. 
     SUMMARY OF THE INVENTION 
     One of the objects of this invention is to provide a means of transporting a dragged farm implement such as a drag harrow which is pulled behind another implement, such as a disc harrow, of the type having retractable wheels for transporting it. 
     Another object is to provide such a means which does not sacrifice any of the operating characteristics of either implement. 
     Another object is to provide such a means which enables the combined implements to be transported substantially as easily as the wheeled implement alone, even when the dragged implement is wider than the wheeled implement. 
     Another object is to provide such a means which is rugged and simple and which can easily be installed on existing wheeled implements if desired. 
     Another object is to provide such a means which is usable with a wide variety of existing wheeled implements and dragged implements. 
     Other objects will occur to those skilled in the art in light of the following description and accompanying drawings. 
     In accordance with this invention, generally stated, improved lift means are provided for transporting a generally horizontal dragged farm implement of the type which is pulled behind a wheeled implement having retractable wheels and operating means for retracting and lowering the wheels. The lift means comprise arm means pivotably mounted on the wheeled implement for releasably engaging the dragged implement and carrying it suspended in a generally vertical position, and linkage means for operatively connecting the arm means to the operating means for retracting and lowering the wheels of the wheeled implement. 
     In the preferred embodiment, the dragged implement is a drag harrow, including a plurality of sections attached to a drawbar. Typical drag harrows are shown in brochure AD-31130-A 3/72 entitled International ® Peg-Tooth Harrows (International Harvester Company, Chicago, Illinois). Such harrows are attached to a single tie point, a considerable distance ahead of the harrow, for proper pivoting of the harrow on turns. 
     In the preferred embodiment, the wheeled implement is a disc harrow, such as those described in brochure AD-3686-D-7 2/75 entitled International Wheel-Controlled Disk Harrows (International Harvester Company). Such harrows include a frame which carries gangs of disc blades. The frame is mechanically attached to a tractor through a hitch. An hydraulic cylinder on the frame is attached by hydraulic lines to a pump on the tractor. The hydraulic cylinder rotates a transverse horizontal bar, the ends of which carry legs on which the wheels are mounted. 
     The preferred lift of the present invention includes a pair of rearwardly-extending arms, the forward ends of which are connected to a second rotatable bar. A linkage between the two rotatable bars causes the arms to rotate through an angle of more than 45°, preferably about 70° ± 10°, from a generally horizontal position to a generally vertical position when the wheels are moved to their lowered, transport, position. The arms are of a substantial length, on the order of 3 to 6 feet long, sufficient to suspend the drag harrow vertically by its drawbar when the disc harrow is raised to its transport position. 
     When the disc and drag harrow are in use, the drag harrow is released from the arms and is pulled a considerable distance, on the order of 5 to 10 feet, behind the disc harrow by tow lines attached to a common tie point on the rear of the disc harrow. Hinges in the arms permit the arms to be folded back onto the frame of the disc harrow. When the harrows are to be transported, the disc harrow is backed sufficiently close to the drag harrow that releasable engagement means (e.g. hooks) at the free ends of the arms engage the drawbar of the drag harrow. As the wheels of the disc harrow are lowered, the drag harrow is raised to its suspended vertical position. Dog legs and telescopic joints in the arms permit considerable lateral motion of the free ends of the arms, and thereby permit the suspended drag harrow to be shifted laterally to either side as the rig is taken through a gate narrower than the drag harrow. The dog legs also position the hooks at the free ends of the arms near ground level, so that the drag harrow needs to be lifted only a few inches to engage the hooks. It has been found that contrary to what might be expected, when the drag harrow is suspended vertically it has little tendency to sway back and forth toward the disc harrow. When the harrows are jostled in transportation, the shock seems to be taken up by a slight lateral movement of the suspended drag harrow. 
     Other aspects of the invention will be more easily understood in light of the following description of the preferred embodiment. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, FIG. 1 is a top plan view of a drag harrow pulled by a disc harrow equipped with one embodiment of lift device of this invention; 
     FIG. 2 is a view in side elevation, partially broken away, of the combination of FIG. 1; 
     FIG. 3 is a view in side elevation of the disc harrow of FIGS. 1 and 2, showing arm portions of the lift device folded onto the disc harrow; 
     FIG. 4 is a view in side elevation, corresponding to FIG. 2, showing the disc harrow and drag harrow positioned for transport; and 
     FIG. 5 is a detail of a dog portion of linkage part of the device of FIGS. 1-4. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, reference numeral 1 indicates a disc harrow equipped with the implement lift device of the present invention, and reference numeral 3 indicates a drag harrow adapted to be lifted by the disc harrow 1. By way of illustration, the disc harrow 1 may be the type sold by International Harvester Company, Chicago, Illinois, as its model 470 Wheel-Controlled Disk Harrow. It will be understood, however, that the invention is equally applicable to equipment of other types, manufactured by others. The disc harrow 1 includes the conventional frame 5 to which are attached conventional tractor hitch 7, forward disc gangs 9, rearward disc gangs 11, and a rear hitch 13. Pillow blocks on the lower side of the frame 5 rotatably support a transverse shaft 17, on the ends of which are welded rearwardly extending legs 19. Spindles 21 on the free ends of the legs 19 rotatably carry wheels 23. A longitudinally extending hydraulic cylinder 25 is pivotally mounted to the frame 5 forward of the shaft 17, as indicated at 27. Hydraulic lines 29 connect the cylinder 25 to an hydraulic pump and control system carried by a tractor, not shown. The piston 31 of the hydraulic cylinder 25 is pivotally connected to an ear 33 on the transverse shaft 17. Extension of the hydraulic cylinder piston 31 rotates the shaft 17 and lowers the wheels 23 for setting the depth of cut of the disc gangs 9 and 11 or for transportation of the disc harrow 1. As thus far described, the disc harrow 1 is entirely standard. 
     About 35 inches behind the wheel-actuating shaft 17, four pillow blocks 35, bolted to the upper side of the frame 5, rotatably support a transverse shaft 37, parallel to the shaft 17. The shaft 37 may, for example, be a 31/2 &#34; pipe. Welded to the shaft 37 are a pair of brackets 39 which carry rearwardly extending arms 41. Each of the arms 41 includes a section of tubing 43 welded to the bracket 39 and a brace 45 welded between the tube 43 and shaft 37. Telescoped within each tube 43 is a pipe 47 to which is welded a collar 49, about 3 inches from the rearward end of the pipe 47. The collar 49 prevents the pipe 47 from slipping entirely into the tube 43. At its free rearward end, the pipe 47 carries one leaf of a hinge 51. The other leaf of the hinge 51 is welded to the forward end of a second pipe 53, which is angled downwardly and rearwardly from the first pipe 47 at an angle of about 40°. The free rearward end of the second pipe 53 has welded to it a clevis 55 in which a hook 57 is pivotally mounted. By way of example, tubes 43 may be two and one half inches in inside diameter, the pipes 47 and 53 may be about 23/8  inches in outside diameter, and the tube 43 and the second pipe 53 may be about 25 inches long. 
     The wheel-actuating shaft 17 and the second shaft 37 are linked to each other by a pair of linkage bars 59, each connected between a dog 61 carried by the wheel-actuating shaft 17 and a dog 63 on the second shaft 37. Each of the dogs 61 and 63 may be formed as a casting, as shown in FIG. 5, integrally with a semicircular sleeve part, the inner surface of which is knurled as shown at 65, and outer wings 67 of which include holes 69 for receiving a U-bolt 71 for holding the dog securely to the shaft 17 or 37. The linkage bar 59 is pivotally connected to the dogs 61 and 63 at its ends. The dogs 61 and 63 are so arranged that movement of the wheels 23 to their fully retracted position, as shown in FIG. 2, fully lowers the arms 41, and movement of the wheels 23 to their fully lowered position rotates the arms 41 upward about 75° to their fully raised position. 
     The drag harrow 3 of this embodiment includes three sections 73, 75 and 77. Each of the sections may be of the type sold by International Harvester Company as its &#34;7 Peg-Tooth Harrow Flexible Section&#34;. In this illustrative embodiment, the outer two sections 73 and 75 are 6 feet wide and the center section 77 is 5 feet 3 inches wide. Each section includes a pair of longitudinally extending braces 79 and transverse bars 81 carrying teeth 83. The longitudinal braces 79 are connected, as indicated at 85, to a 17-foot drawbar 87. Conventional tie points 89 are provided on the forward edge of the drawbar 87 for attaching the drag harrow 3 to the rear hitch 13 on the disc harrow frame 5. The drag harrow 3, as thus far described, is entirely conventional. 
     The tie points 89 on the drag harrow 3 are connected to the hitch 13 on the disc harrow frame by flexible steel cables 91. Cables 91 are employed rather than steel rods in order to permit the drag harrow 3 to be lifted without disconnecting it from the disc harrow. 
     Two hanger brackets 93 are bolted to the drawbar 87. The hanger brackets 93 are spaced and sized to receive the hooks 57 on the arms 41. 
     When the disc harrow 1 and drag harrow 3 are in use, the rearward sections 53 of the arms 41 are folded back onto the disc harrow 1 as shown in FIG. 3. In this position, the telescoped sections 47 have no tendency to come loose, and the arm extensions 53 provide additional weight for the disc harrow 1. The disc harrow 1 and the drag harrow 3 operate in all respects in their conventional manner. The distance between the disc harrow and drag harrow may, for example, be 7 feet, and the two harrows thus operate substantially independent of each other. The tie lines 91 permit the drag harrow 3 to track properly around turns and to conform to rolling land. 
     When it is desired to transport the harrow, the rearward extensions 53 of the arm 41 are lowered to the position shown in FIGS. 1 and 2. The tractor and disc harrow 1 are backed sufficiently toward the drag harrow to permit the hooks 57 to engage the hangers 93. The hydraulic cylinder 25 is then actuated to rotate the wheel-actuating shaft 17, thereby lowering the wheels 23 and raising the arms 41, as shown in FIG. 4. It will be seen that the initial lifting movement of the harrow 3 is nearly vertical, so that the teeth 83 tend to be lifted out of the ground. 
     In its transport position, shown in FIG. 4, the harrow 3 hangs freely in a vertical position from the hooks 57. In this position, the drag harrow 3 adds very little to the total length of the disc harrow and does not seriously disturb the weight distribution of the disc harrow 1. If a gate narrower than the drag harrow 3 should be encountered, the angle between sections 47 and 53 of the arms 41 and the telescopic fit of the sections 47 in the tubes 43 permit the arms 53 to be pivoted to the right or left to allow one side of the harrow 3 to pass through the gate, and then permit the arms to pivot to the other side to allow the rest of the drag harrow 3 to pass through. 
     The drag harrow is easily returned to its operative position by simultaneously raising the wheels 23 and pulling the disc harrow 1 forward. The drawbar 87 is lifted off hooks 57, the arms 41 are folded back along hinges 51, and the harrows are ready for use. 
     The drag harrow 3 is readily separated from the disc harrow 1 by disconnecting the lines 91 from the rear hitch 13. When the drag harrow is not in use, the arms may be kept in their folded-back position to add weight to the disc harrow, or the pipes 47 may be pulled from tubes 43 and stored. If desired, the linkage arms 59 may be disconnected, to prevent the arms 41 from moving with the wheels 23. 
     Numerous variations in the implement lift of this invention, within the scope of the appended claims, will occur to those skilled in the art in light of the foregoing disclosure. Merely by way of example, the lift may be mounted on other tillage implements with retractable wheels, such as field cultivators and chisel plows. The construction of the arms 41 may be altered without losing all the advantages of the present invention. The dogs 61 and 63 may be welded to their respective shafts, or other linkage may be employed. To make the lift more easily adaptable to different sizes and types of implements, and to avoid the necessity of any welding, all of the parts may be bolted together. For example, not only the dogs 61 and 63, but also the sleeves 39 and braces 45 may be bolted to the shaft 37, to permit the arms to be moved laterally; the sleeves 39, hinges 51 and clevises 55 may all be castings including stubs which slide into the tubes and pipes 43, 47 and 53 respectively and are bolted in place; the pillow blocks 35 may be replaced by sleeve bearings held to the top of the disc harrow frame 5 by U-bolts held by mounting plates below the frame. The arms may be closer together to accomodate wings on the disc harrow. Different types of drag harrows may be employed. The drawbar may be foldable, and the drag harrow may be transported folded. If less flexible tie lines 91 are used, they may be unhooked from the tie point 13 before the harrow is lifted. Although the use of the lift of the present invention with a wheeled implement is for many reasons preferred, at least some of the advantages of the lift may also be enjoyed when it is used on a non-wheeled tillage implement having a two or three-point hitch for lifting the implement. These variations are merely illustrative.