Abstract:
A wetland foliage cutter designed for towed operation behind an ATV machine has adjustable buoyancy and a vertically adjustable wheel suspension. A tow frame holds a cutter drum for drag rotation about a horizontal rotational axis. A multiplicity of cutter blades are welded to the cutter drums for cutting or crushing wetland foliage as it rolls over it. The tow frame also holds a torsion bar wheel suspension that may be rotated and fixed at a desired angle and height for complete or partial support of the implement weight.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to mechanical devices for conditioning the wetland habitat of waterfowl. In particular, the invention comprises a towed machine for breaking down excessive vegetation over a shallow waterfield.  
         [0003]     2. Description of Related Art  
         [0004]     Shallow water wetlands in warm or temperate climates such as are found in the southern United States, are frequently rich in plant nutrients. Consequently, these regions produce a great variety of vegetation. Among these varieties are an abundance of seed and grain plants that provide essential nutrition for migratory waterfowl. In some cases, unfortunately, the sheer abundance of this growth seems to defeat the potential benefit to the waterfowl. In some places, such verdant growth appears to discourage waterfowl presence by possibly creating a canopy that obscures the water beneath the vegetation overgrowth. Additionally, due to the height of this vegetation, the waterfowl have difficulty removing the seed heads for consumption.  
         [0005]     To encourage conservation and support of the migratory bird population, it has been proposed to clear or at least thin the vegetation covering significant areas of wetland. Such proposals include removal of the overgrowth in selected areas, or more precisely, breaking down the overgrowth below the water surface level to facilitate feeding and visitation.  
         [0006]     Although traditional agricultural machines have been developed and are used to crush and disintegrate the stalks and stems of harvested plants in a traditional farm field, such prior art machines are not suitable for the boggy terrain of wetlands and tidelands.  
       SUMMARY OF THE INVENTION  
       [0007]     In summary, the invention comprises a towed vehicular implement having a basic box frame with a draft yoke and hitch socket. Transverse of the frame box tow axis, a drum support bar is secured to the frame box. At opposite distal ends of the drum support bar are dependent bearing mounts. A cylindrical chopper drum is secured to the bearing mount ends for free rotation about a horizontally disposed cylindrical axis. A multiplicity of radially projecting chopper blades are secured to the chopper drum surface in a predetermined pattern. The end heads of the drum are perforated by plugged nipples.  
         [0008]     Also secured to the frame box, transversely of the tow axis, is a torque bar having wheel struts at opposite distal ends of the torque bar. A retractable wheel suspension comprising wheel struts projecting from a torque bar in a general direction away from the draft yoke. The torque bar is secured to the frame box by journal bearings to accommodate rotation of the torque bar about it&#39;s longitudinal axis. Secured to the torque bar at the approximate mid-span is a torque bracket and bracket leg. At the distal ends of the wheel struts are respective wheel forks. Each wheel fork secures a carriage wheel that is mounted for rotation about a horizontal axis that is transverse to the vehicle tow axis.  
         [0009]     Spanning between the torque bracket leg and a clevis post secured to a forward element of the frame box is an implement turnbuckle. The distal end of each turnbuckle rod is secured to a clevis connector. One clevis connector is secured by a shear pin to the torque bracket leg whereas the other clevis connector is secured by a shear pin to frame post.  
         [0010]     In the wetland environment of a shallow water field, the invention is preferably drawn by a 4-wheeled ATV draft vehicle having large knobby tires for buoyancy and traction. The implement cutting drum is passively driven by the towed movement over field 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The advantages and further features of the invention will be readily appreciated by those of ordinary skill in the art as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference characters designate like or similar elements throughout.  
         [0012]      FIG. 1  is a plan view of the invention assembly and  
         [0013]      FIG. 2  is a side elevation view of the invention assembly 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     Referring to  FIGS. 1 and 2 , the invention broadly comprises a frame structure  10  to which a roller drum  30  is secured for rotation about a horizontal cylinder axis  38 . Also secured to the frame  10  for limited rotation about a horizontal axis  64  is a retractable wheel suspension assembly  50 . A suspension setting turnbuckle  70  secures the suspension assembly wheels  58  at a desired angular position about the horizontal axis  64  relative to the frame  10 .  
         [0015]     With specific regard to the frame  10 , a traditional box construction  12  of welded structural sections such as steel or aluminum tube, channel or I-beam provides a basic assembly platform. A draft yoke  16  has a trailer hitch socket  18  secured to the frontal apex of the yoke. The trailing ends of the draft yoke  16  are secured to the respective bottom ends of a pair of risers  14 . The upper ends of the risers  14  are secured to the front corners of the box  12 . The length of the risers  14  is determined by the hitch elevation of the desired draft vehicle and the diameter of the roller drum  30  with the objective of keeping the towing force plane roughly horizontal through the roller drum axis  38 . A truss strut, not shown, may be secured between the plane of the box  12  and the plane of the draft yoke  16 . Approximately along the tow center plane  26 , a clevis post  24  is rigidly secured to the topside of the box  12 . The clevis post  24  is transversely bored with an aperture to receive a transversely aligned shear pin  28 .  
         [0016]     The wheel suspension  50  comprises a torque bar  52  having a pair of wheel struts  54  projecting substantially normally from opposite ends of the torque bar. At the distal ends of the wheel struts  54 , a wheel fork  56  is secured to thru-axle mount respective wheels  58 . The suspension assembly  50  is secured to the frame box  12  by a pair of journal caps  66  aft of the drum support bar  38  for partial rotation about the horizontal axis  64  of the torque bar. Approximately mid-length of the torque bar  52 , torque bracket  60  is non-rotatively secured to the torque bar  52  structure as by welding. Upstanding from the torque bracket  60 , a bracket leg  62  is welded or otherwise rigidly secured to the bracket  60 . Near the distal end of the bracket leg  62 , an aperture traverses the bracket leg thickness to receive a shear pin  68 .  
         [0017]     An implement turnbuckle  70  having clevis connectors  75  and  78  is secured to the bracket leg  62  and clevis post  24  by means of the shear pins  28  and  68 . Additionally, the turnbuckle  70  comprises a right-hand threaded rod  74  that supports the end clevis  75  and a left-hand threaded rod  77  that supports the end clevis  78 . The right and left-hand threaded rods  74  and  77  are structurally linked by an internally threaded sleeve  72 . Rotation of the sleeve  72  over the rotationally fixed rods  74  and  77  advances the rod lengths axially in or out of the sleeve  72  bore in respectively opposite directions. Hence, the suspension wheel  58  may be raised or lowered relative to the horizontal plane of the frame  10  by reducing or increasing the distance between the shear pins  28  and  68 .  
         [0018]     Those of ordinary skill in the art will recognize that the turnbuckle  70  function may be accomplished by numerous other mechanical devices such as a jack-screw or pressurized fluid strut.  
         [0019]     A drum support bar  20  transversely spans the box  12  and is rigidly secured thereto for supporting the bearing mount risers  22  at opposite ends of the bar. The roller drum assembly  30  is secured for rotation between these risers  22  about the cylinder axis  38 . The roller drum assembly  30  comprises the drum  32  having end closure heads  33 . One or both heads  33  is perforated by a recloseable aperture  36  such as an internally threaded nipple and externally threaded plug. The drum surface carries a multiplicity of radially set chopper blades  34 . The alignment pattern of the blades  34  over the surface of the drum  32  may take many forms. The presently preferred embodiment, however, provides a blade of about 6″ to 9″ length and about ¼″ thickness. Blade width as measured from the drum  32  surface radially to the knife edge is preferably about 3″ to 4″. This embodiment sets the blades  34  on the drum surface  32  in three, axially parallel rows spaced  1200  apart around the drum perimeter. Between each blade along a respective row is an approximate 4′ space. The longitudinal placement of the blade-space order is shifted between adjacent rows to assure a full transverse cut for each revolution of the drum.  
         [0020]     A non-illustrated, acceptable alternative alignment of the blades  34  may include two or more helical developments over the drum surface with each blade  34  set in parallel alignment with the drum axis  38  but each blade having a helically offset position relative to the adjacent blades. Other alignment patterns are taught within the disclosure scope of U.S. Pat. No. 6,968,907 to R. L. Raper et al, which is incorporated herein.  
         [0021]     The present invention is designed and developed to roll down and sever or crush the stalks of native vegetation growing in a flooded wetland impoundment. One of the important invention objectives is to expose open water areas within the vegetated wetland to attract waterfowl visitation. The soil substrate of such impoundments may vary considerably from firmly compacted to a silted bog. Traditional farm machinery is usually too heavy for operation in such an environment. Light duty recreational machines such as All Terrain Vehicles (ATV) equipped with large volume, low pressure tires with raised knob tread patterns are specifically designed for operation under such conditions. Hence, the invention is particularly well suited for operation in tow behind a suitably outfitted ATV machine. Due to the relatively large displacement volume represented by the drum  32  and the low pressure tires of implement wheels  58 , the implement may be constructed for partial, or in some cases, full buoyancy. For buoyancy control and, more specifically, control over the force required to cut the wetland foliage against the natural anvil of a boggy bottom, the heads  33  of the drum  32  include a fill nipple  36 . To increase the total weight of the implement, water, for example, may be added to the drum  32  interior through the nippled aperture  36  which is closed by a threaded plug.  
         [0022]     Not to be overlooked, is the buoyancy of the tires  58 . If the tires are filled only with air, for example, the wheel assembly  58  may contribute positively to the overall machine buoyancy. On the other hand, if greater weight is required, the tire casings may be filled with water or even heavier fluids as is often used with traditional agricultural and construction machinery. The buoyancy characteristics of the implement structural elements should also be considered. If those elements are thin wall hollow tube and the joints are all welded fluid tight it may be possible to achieve full frame buoyancy. The same is possible for the suspension assembly  50 .  
         [0023]     The adjustable position of the of the suspension wheels  58 , allows the operator infinite control over the penetration depth of the chopper blades  34 . If the wetland substrate is extremely soft and boggy, the wheels may be set to a support plane considerably below the bottom tangent plane of the drum  32  to prevent the drum from becoming mired in the boggy substrate. Additionally, the suspension wheels  58  may be lowered for implement towing over paved roads to prevent damage to either the road or the implement chopper blades  34 .  
         [0024]     Although the invention has been described in terms of specified and presently preferred embodiments which are set forth in detail, it should be understood that this is by illustration only and that the invention is not necessarily limited thereto. Alternative embodiments and operating techniques will become apparent to those of ordinary skill in the art in view of the present disclosure. Accordingly, modifications of the invention are contemplated which may be made without departing from the spirit of the claimed invention.