Abstract:
This is a large rotatable cutter head primarily useful in masticating vegetation ranging from grasses to large trees. The inventive cutter head is typically mounted on an articulating arm on a tractor or tread-based vehicle. Depending upon the size of the arm and its maneuverability, the cutter head may be used to cut and grind vegetation variously from the ground surface to many feet off the ground. The rotatable cutter head assembly includes a number of rotating cutters mounted inside the periphery of the assembled drum and that spin freely outside the diameter of that drum and, upon contact with vegetation, rotate into the drum assembly. The invention includes combinations of the cutter head with the support vehicle or articulating arm and methods of using the cutter head.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to a large rotatable cutter head primarily useful in masticating, grinding, and mulching vegetation ranging from grasses to large trees. The inventive cutter head is typically mounted on an articulating arm on a tractor or tread-based vehicle. Depending upon the size of the arm and its maneuverability, the cutter head may be used to cut and grind vegetation located variously from the ground surface to many feet off the ground. The rotatable cutter head assembly includes a number of rotating cutters mounted inside the periphery of the assembled drum. The rotating cutters spin freely; their swing forms a circle extending from outside the diameter of the drum assembly (where they contact the vegetation) and into the drum assembly. The invention includes combinations of the cutter head with the support vehicle or articulating arm and methods of using the cutter head. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0002]    [0002]FIG. 1 shows a side view of the inventive cutter head assembly.  
         [0003]    [0003]FIG. 2 shows a side view of individual section of cutter head assembly and the attendant cutters.  
         [0004]    [0004]FIG. 3 is a side view, close-up of an individual cutter or cutter knife.  
         [0005]    [0005]FIG. 4 is a side view of an individual disk subassembly section without cutter blades.  
         [0006]    [0006]FIG. 5 is an edge view of the FIG. 4 subassembly.  
         [0007]    [0007]FIG. 6 shows various views of a housing suitable for the cutter head assembly.  
         [0008]    [0008]FIG. 7 shows the housing and cutter head assembly mounted on the articulated arm of a tracked vehicle. 
     
    
     DESCRIPTION OF THE INVENTION  
       [0009]    In general, this invention deals with a rotating cutter assembly and its surrounding support components. It is most useful when mounted on a self-propelled, high ground clearance machine. The supporting machinery is likely, most often a diesel powered, tracked vehicle having hydraulically driven accessories. Such machinery is sold commercially by, amongst others, the Caterpillar Company for use as excavators. A vehicle typical of this type is shown in the Figures. The rotating cutter assembly will typically be mounted at the end of the articulated arm allowing ease of use at levels variously from the surface of the ground to the end of the extended articulated arm. In concept, my design is a more-flexible design intended to replace older designs that were susceptible to frequent breakage. The repair and rebalancing of the older designs was often time-consuming and since, such repair takes place in the field, fairly expensive. My design has easily replaceable cutters.  
         [0010]    The inventive cutter head assembly  100  shown in FIG. 1. It is shown there without drive gear or drive motors although, in use, such may be desirable. In any case, the cutter head assembly  100  may be made up of three major conceptual parts. The first major component group —all of these will be discussed in more detail below —are the cutters or cutter knives themselves  102 . The second major component, to which the cutters are attached, is the cutter drum  104 . The third major section is the drive shaft  106 .  
         [0011]    In operation, the drive shaft  106  is fixedly attached to the drum assembly  104 . A motor of some type, e.g., electric, hydraulic, internal combustion, etc, is used to turn the drive shaft  106 , indirectly or directly, and to drive rotating cutter drum  104 . The drive motor may be located remotely from the drive vehicle and desirably is placed on the end of the articulating arm near the cutter head assembly. A suitable placement of the drive motor is shown below.  
         [0012]    Cutters  102  are free to rotate about cutter axles  108 . Centrifugal force swings the cutter heads  102  out from the peripheral confines of cutter drum  104 . The cutters  102  are placed within the drum assembly  104  in such a way that they are desirably able to rotate 360° freely about the cutter axle cutter shaft  108 . The diameter of the assembly  100 , from tip to tip of cutters  102 , might typically be in the range of two to three feet. Typical rotational speeds for the assembly  100  would be from 800 to 2,000 rpm, preferably 1,000 to 1,500 rpm. Although sizes, speeds, rates, etc. are provided throughout the specification, they are only given as examples of useful data and are not intended to limit the claims in any way.  
         [0013]    A typical drive shaft  106  might be four inches, more or less as the specific design dictates, in diameter. The design shown in FIG. 1 typically would be made from steel plate from 1 to 2 inches in thickness. The cutters or knives  102  might be sized to be three to five inches in width, preferably about four inches in width.  
         [0014]    Rotating drum assembly  104  in FIG. 1 may be made up of a series of disk subassemblies such as are shown in FIGS. 2, 4, and  5 . Subassembly  200  (as shown in FIG. 2 with rotatable knives  102  attached) may be made up in sheet steel sections, perhaps welded together, although other designs are similarly appropriate. For instance, the subassembly may be cast or forged. The cutter drum subassembly  200 , as shown in FIG. 2, may be made up of a full disk  202  into which the rotatable blades  102  are mounted via a knife axle shaft  204 . A cutout disk  206  may be used variously for providing a flywheel effect, a measure of additional cutting action, and additional stiffness. A spacer  208  is also shown. As may be seen in FIG. 5, a pair of hubs  210  and  212  may be used to join a specific subassembly  200  to an adjoining subassembly  200  in a rotating assembly using, e.g., dowels  214  or the like. The drive shaft  106  as shown in FIG. 1 passes through opening  216  and may be driven by a key  218  as shown in FIG. 2. Preferably each disk subassembly  200  is individually driven from drive shaft  106 .  
         [0015]    [0015]FIG. 3 shows an individual cutter knife  102  as it would be mounted between two rotating disks  202 . Generally, although not necessarily, a number of cutter knives  102  are mounted on a single axle shaft  220 . The knife axle shaft  220  preferably passes from one end of the rotating cutter assembly  100  as shown in FIG. 1 to the other and allows ease of cutter  102  replacement by the removal of the shaft  220  from one end of the assembly or the other. It is desirable to include bushings or bearings about each of the axles and within the rotating bore of cutter head  102 . The cutter knife or blade  102  is shown to be a weighted towards the outer end and having sharpened edges  221  at those ends. The approximate “Y” shape to the cutter knife  102  allows the sharp ends to approach the target vegetation with a sharp edge and increases the efficiency of the cutter assembly. These cutter heads  102  are more than mere flails in that they are able to rotate through 360° in traveling through the cutter assembly and, in the depicted variation, rotate only in a single axis about their respective axles. From a design standpoint, the cutter blades  102  are desirably formed of a single piece of metal or at least an assembled, integrated piece of metal when, e.g., a tougher leading edge is introduced onto the leading edge of the blades by, e.g., welding.  
         [0016]    As may be apparent from the nature of the operation of this device, it is desirable to install it in a partial housing adapted to protect an operator from debris created during the operation of the device, from rocks that may be picked up during low level use, and, perhaps, from portions of blades broken during use. This design of the cuter head assembly allows the individual cutters to rotate at a speed higher than the drum peripheral speed and so to improve the efficiency of the cutters in macerating vegetation.  
         [0017]    [0017]FIG. 6 shows a suitable enclosure  300  in front view  302 , in left side view  304  (the “bearing end” view), and in right side view  306  (the “drive end” view). The cutter assembly fits within the housing, and the cutter assembly axle extends between and extends through cutouts  308 ,  310  in the housing side walls. Bearing retainers (not shown for clarity sake) would be attached to the side walls at cutouts  308 ,  310  to support the cutter assembly axle. The drive motor, e.g., a hydraulic motor, would be situated on the motor mount  312  (shown exploded from the housing  300 ) and located behind guard  314  as seen in right side view  306 . The drive motor and the motor mount  312  would be mounted at site  316 . The drive motor typically would drive the cutter head via one or more belts. Other drive mechanisms would be acceptable, e.g., gear drives in rubber-unfriendly habitats. A skid component is shown in the FIG. 5 drawings.  
         [0018]    [0018]FIG. 7 shows the cutter assembly  400  mounted at the end of an articulating arm assembly  402  that, in turn, is a portion of an excavator or back-hoe  404  such as might be made by the Caterpillar Company. Supporting the inventive rotating cutter assembly  400  and the hydraulic motor  406  is the arm generally controlling the height of the assembly&#39;s reach by its hydraulic cylinder  410 . Similarly, some measure of reach and placement is had via control of arm  412  by hydraulic cylinder  414 . Orientation of the cutter assembly is had via hydraulic control cylinder  418 . Although not shown on this depiction, the distal tip of the arm assembly  402  may be adapted to allow rotation of the cutter assembly  400  about the axis of arm  412 . The controls mentioned herein are those normally associated with such an excavation device. In any case, the various controls are for the purpose of moving the rotating cutter against various target vegetation.  
         [0019]    The inventive rotating cutter assembly is used in the following fashion: the head is rotated at a speed sufficient to move the cutter blades out of the diameter of the support drum assembly. This allows the blades to contact the vegetation. As a blade hits the vegetation, it both cuts vegetation and rotates into the drum. As the drum then turns, the cutter blade or knife is free to rotate back out of the periphery of the drum into a position for further cutting. When used with a tracked vehicle or other vehicle such as shown in FIG. 7, the cutter assembly is placed in position to contact vegetation by appropriate movement of the articulated arm.  
         [0020]    This invention has been described by use of examples and although various sizes and dimensions and speeds are mention in the text above the invention is obviously not so limited.