Abstract:
The brush cutter has an elongated frame and a series of cutting discs mounted in line along that frame, and can be mounted in a wing-plow arrangement via wing-plow attachments. The wing-plow attachments comprise a wing-plow mast having a first raisable connection and a wing-plow push bar having second raisable connection. The elongated frame is connected at both ends thereof to the first and second raisable connections respectively, such that both ends are independently adjustable in height by the wing-plow mast and the wing-plow push bar.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional application No. 61/714,880, filed Oct. 17, 2012, the disclosure of which is hereby incorporated by reference. 
     
    
     FIELD 
       [0002]    This invention pertains to brush cutters for clearing shrubs and other vegetation from road shoulders, and more particularly it pertains to brush cutters that are mountable to road graders and snow-plow trucks. 
       BACKGROUND 
       [0003]    The maintenance of roadways in the countryside and along wood lots require periodic cutting of alders, poplar trees and other fast growing shrubs along the road shoulders, to prevent vegetation from spreading onto the roadways. This work is done by various apparatus including brush cutters mounted on farm tractors and front-end loaders. 
         [0004]    Examples of these brush cutters are disclosed in the following documents. 
         [0005]    U.S. Pat. No. 5,123,462 issued on Jun. 23, 1992 to T. A. Davision. The brush cutter described in this document has a large cutting disc mounted on a frame that is supported to a front-end loader. The disc can be swung side-to-side in the front of the loader. 
         [0006]    U.S. Pat. No. 6,311,464 issued to H. Neuerburg et al. on Nov. 6, 2001. This document discloses a series of disc-like cutters mounted inline on a bar. The bar is suspending at its middle to an arm mounted to the back of a tractor. The arm can be swung sideways to mow grass alongside the tractor. 
         [0007]    CA Patent 510,271 issued to Earl W. Holmes on Feb. 22, 1955. The apparatus disclosed in this document comprises a sickle bar extending from an arm having a pivot at each end. The arm extends from a turntable on the frame of a truck. The sickle bar is movable to cut grass along the near slope and the far slope of a ditch. 
         [0008]    CA Patent 914,430 issued to V. D. L. Cornelis on Nov. 14, 1972. This document discloses a pair of mower rotors mounted side-by-side on the three-point hitch of a farm tractor. The mower rotors are mounted offset from the line of travel of the tractor, such as to mow a strip of grass alongside the tractor. 
         [0009]    CA Patent 1,004,858 issued to Pieter A. Oosterling et al. on Feb. 8, 1977. This document discloses a series of disc-like cutters mounted inline on a bar extending from the three-point hitch of a farm tractor. The bar-type cutter extends sideways from the tractor such as a conventional sickle bar type hay mower. 
         [0010]    Although the apparatus of the prior art deserve undeniable merits, it is believed that a more convenient way for clearing brushes along road shoulders is to do it using a brush cutter mounted as a wing plow on a road grader or on a similar snow-plowing vehicle. Advantages of such mounting are numerous and include the fact that its operation is as easy as operating a wing plow. 
       SUMMARY 
       [0011]    In the present invention, there is provided a brush cutter mounted as a wing plow on a road grader, a snow plow truck or other snow-plowing vehicle. 
         [0012]    Broadly, in one aspect of the present invention, there is provided a road vehicle having wing-plow attachments and a brush cutter mounted as a wing plow to the wing-plow attachments. The brush cutter has an elongated frame and a series of cutting discs mounted in line along that frame. The wing-plow attachments comprise a wing-plow mast having a first raisable connection and a wing-plow push bar having second raisable connection. The elongated frame is connected at both ends thereof to the first and second raisable connections respectively, such that both ends are independently adjustable in height by the wing-plow mast and the wing-plow push bar. 
         [0013]    This mounting of the brush cutter is as agile as a wing plow to clear road shoulders. The brush cutter can be manipulated to leap over mail boxes, fence posts, large rocks, stumps and driveway markers, whether these obstacles are located at the near end or the far end hereof. 
         [0014]    In another aspect of the present invention, the hydraulic valves used to operate the brush cutter are the same valves as those used to operate a wing plow and these valves are used in a same way as to operate a wing plow, such that the brush cutter is easily workable by snow-plow operators. 
         [0015]    This brief summary has been provided so that the nature of the invention may be understood quickly. A more complete understanding of the invention can be obtained by reference to the following detailed description of the preferred embodiment thereof in connection with the attached drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    A preferred embodiment of the present invention is illustrated in the accompanying drawings, in which like numerals denote like parts throughout the several views, and in which: 
           [0017]      FIG. 1  illustrates a partial side view of a road grader and a preferred brush cutter mounted to the road grader as a wing plow; 
           [0018]      FIG. 2  is a partial perspective side view of the road grader and a first example of a brush cutter mounted to the road grader; 
           [0019]      FIG. 3  is a front view of the road grader and brush cutter adjusted to different positions; 
           [0020]      FIG. 4  is a partial top view of the road grader and brush cutter; 
           [0021]      FIG. 5  is a detail view of the near connection on the snow plow mast on the brush cutter, as shown in detail circle  5  in  FIG. 4 ; 
           [0022]      FIG. 6  is a detail view of the far connection on the snow-plow push-bar and the brush cutter, as shown in detail circle  6  in  FIG. 4 ; 
           [0023]      FIG. 7  is a partial plan view of the brush cutter first example illustrating an alignment relative to its direction of movement. 
           [0024]      FIG. 8  is an oblique view showing a second example of a brush cutter. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Referring back to  FIG. 1  there is illustrated therein, the preferred brush cutter  20  mounted as a wing plow on a road grader  22 . The preferred brush cutter  20  has a bar-like elongated frame  24  and a series of cutting discs  26  mounted in-line to this frame  24 . 
         [0026]    The brush cutter  20  is supported to the road grader  22  at two connection points. The connection point closer to the road grader  22  is referred to as the near end connection  40  and the other connection point is referred to as the far end connection  42 . Similarly, the portion of the brush cutter closer to the road grader  22  is referred to as the near end  44  and the portion  20  farther away from the road grader is referred to as the far end  46 . 
         [0027]    Referring to  FIGS. 1-5 , the near end connection  40  has a portion thereof that is integrated in the snow plow mast  48  of the road grader  22 . The snow plow mast  48  has an hydraulic cylinder mounted therein, such that the near end connection  40  can be lifted up and lowered down using an hydraulic valve in the cab of the grader  22 . The hydraulic valve mentioned above is one that is normally used to control the movement of a wing plow. This hydraulic valve belongs to the wing-plow valve bank. The snow plow mast  48  is of a conventional type for supporting a wing plow, and therefore no further explanation is deemed necessary to describe this mast. 
         [0028]    The near end connection  40  consists of a clevis  50 , a plate  52 , and a pin  54  passing through the clevis  50  and through the plate  52 . Preferably, the plate  52  is mounted to a pivot  56  having a vertical axis of articulation, although this is not essential. The pivot  56  is mounted to a block that is movable inside the mast  48 . 
         [0029]    Referring back to  FIG. 1 , the preferred brush cutter  20  has an extension  58  on the near end  44  thereof. This extension has a desired length for positioning the brush cutter  20  at a desired lateral distance from the road grader  22 . Similarly, the total length of the elongated frame  24  and the number of cutting discs  26  in the preferred brush cutter  20  are determined by choice of the designer. 
         [0030]    The articulation of the brush cutter  20  is limited to vertical displacement along the mast  48 ; a horizontal angular sweep as indicated by arrow  60  in  FIG. 4  about the pivot  56 , and a vertical angular movement in the direction of arrow  62  in  FIG. 3 , about the pin  54 . A restriction in the movement of the preferred brush cutter  20  along these orthogonal planes ensures that the cutting discs  26  remain parallel to the ground surface being cleared. 
         [0031]    It will be appreciated that the expression “parallel to the ground” as used herein may also include a setting of each disc  26  where the leading edge thereof is slightly closer to the ground that the trailing edge, for providing a relief in the cut being made. 
         [0032]    The movement of the brush cutter  20  about the pivot  56  is provided to set the brush cutter  22  at an angle from the direction of travel of the road grader  22  such that the path of each cutting disc  26  overlap each other slightly as illustrated by arrows  64  in  FIG. 7 . It will be understood that once this position is set, there is no need for further movement of the brush cutter  20  about the pivot  56 , and therefore, this pivot may be replaced by an appropriate curvature in the plate  52 , for example. 
         [0033]    The far end connection  42  retaining the far end of the brush cutter  20  to the road grader  22  is better illustrated in  FIG. 6 . The far end connection  42  is made in a similar manner as the near end connection  40 . The far end connection  42  is made of a first clevis  68  on the push bar  70  of the road grader  22 ; a second clevis  72  mounted to the frame  24  of the brush cutter  20 , and a linkage  74  joining the first and second clevises  68 , 72 . A horizontal pin  76  extends through the linkage  74  and through the second clevis  72  for providing articulation of the push bar  70  in a vertical plane relative to the position of the brush cutter  20 . The linkage  74  is mounted to the first clevis  68  on a vertical pivot  78  for accommodating horizontal angular movement of the push bar  70  relative to the position of the brush cutter  20 . 
         [0034]    The push bar  70  on the road grader  22  is of the type being extensible by way of a first hydraulic cylinder  80  and raisable by way of a second hydraulic cylinder  82 . The push bar  70  is of the type where actuation of both hydraulic cylinders  80 ,  82  are controlled by hydraulic valves in the wing-plow valve bank as mentioned before. 
         [0035]    The push bar  70  on the road grader  22  preferably has a shock absorber  84  thereon to absorb shocks that might be encountered during the operation of the brush cutter  20 . 
         [0036]    The push bar  70  is mounted to the road grader in a way that is conventional for supporting a wing plow, and therefore no further explanation is deemed necessary relative to this element. 
         [0037]    Referring particularly to  FIG. 3 , it will be appreciated that the structure of the connections  40  and  42  makes it possible to move the brush cutter  20  in many different positions while maintaining the cutting discs  26  in a substantially parallel alignment with the ground surface being cleared. Some of these positions are illustrated in  FIG. 3 . 
         [0038]    The first position of the brush cutter  20  shown at label  90  is a horizontal position where the cutting discs  26  are maintained parallel to a road surface. The second position  92  has the far end  46  of the brush cutter adjusted lower than the near end  44 , for clearing a road shoulder that is sloping downward, below a horizontal alignment from the road surface for example. The third position  94  has the far end  46  raised higher than the near end  44  for use when the road grader  22  has one side riding into a ditch  20  for example. The fourth position  96  has both the near end  44  and the far end  46  raised relative to the road surface, for use when the road grader is riding with both sides thereof into a ditch for example. The fifth position  98  has the near end much higher than the far end, for leaping over a driveway marker for example. The position labeled as  100  is a stow away position with the brush cutter  20  raised in a near-vertical alignment. 
         [0039]      FIG. 8  shows another example embodiment of a brush cutter  110  in detail. The brush cutter  110  has an elongated bar frame  112  with a front side  114  and a rear side  116 , and a plurality of adjacent cutting discs  118 ,  120 ,  122 ,  124 ,  126  extending lengthwisely along it. More particularly, 5 cutting discs are used in this case, although a different number, such as between 3 and 12, preferably between 4 and 8, can be used in alternate embodiments. Each cutting disc can be made of thick steel plates to prevent deformation in use, and can preferably be fitted with replaceable teeth. The rotational speed of these cutting discs is selected to provide cutting and mulching of the material being cleared. The cutting discs all extend along a common plane and protrude slightly out of the front side  114  of the elongated bar frame  112  in order to be exposed to bushes, shrubs, small trees, and the like constituting the brush the brush cutter is intended to cut. 
         [0040]    Brush tends to be of highly uneven constitution and it is often the case that not all cutting discs use the same amount of power at the same time. For instance, a small tree is one example of something that requires a significant amount of power to cut through. If a small tree comes into contact with one of the cutting discs while the other cutting discs are only in contact with softer material, the specific disc the small tree is in contact with will require power to be cut by the cutting disc it is against, but the other cutting discs will likely not require as much power. Statistically, it can be highly unlikely that power above a given specified requirement be required at any given time. Henceforth, in this embodiment, a single motor  128  (hydraulic in this case) is used, the power of which is distributed amongst the cutting discs by a power transfer mechanism  130 . It will now be understood that this arrangement can be significantly less costly than providing each one of the cutting discs with a specific motor offering the maximum power each individual cutting disc is expected to require at some point in time. 
         [0041]    In this specific embodiment, the motor  128  is directly mounted on the shaft of one of the cutting discs and the power is distributed to the shafts of the other cutting discs by corresponding belt and sheave arrangements. More specifically, one belt and sheave arrangement including its tensioning pulley is used between each pair of adjacent cutting discs. Belt and sheave arrangements were used in this example rather than gearing or chain and sprocket arrangements given that they allowed satisfactory performance at a lower cost. Moreover, it will be noted that the motor  128  is mounted on the shaft of a central one of the cutting discs  122  in this embodiment, and therefore transfers power to cutting discs located on both sides. Henceforth, to reach the cutting discs  126 ,  118  located at each opposite end, the power is carried across a maximum of two belt and sheave arrangements. This configuration is believed to lead to a lesser likelihood of belt failures than an embodiment where the motor would be located at one end of the elongated frame and the power thereby travel across a greater number of belts, for instance. 
         [0042]    In this example where 5 cutting discs are used, each having a 2 or 2¼″ kerf, triple sheave arrangements were found to offer satisfactory ruggedness and to be better than double sheave arrangements. It will be noted that a housing or cover, not shown in  FIG. 8 , is used to cover and protect the power transfer mechanism  130  during use. 
         [0043]    The brush cutter  110  also has a brush deflector bar  132  mounted on the front side thereof to deflect small trees downward in the front of and under the brush cutter  110 . In the specific example shown in  FIG. 8 , the brush cutter is designed for use in a wing-plow application such as presented above. The elongated bar frame  112  can thus be said to have a proximal end  134  intended to be near the vehicle during use, and a distal end  136  opposite the proximal end  134 . Rather than being parallel to the elongated frame  112 , the brush deflector bar  132  slopes both downwardly and rearwardly from the proximal end  134  to the distal end  136 . In a wing plow application, an objective is to push trees both downwardly and outwardly, away from the vehicle. This oblique sloping configuration can help achieving this. 
         [0044]    It will also be noted that in this specific embodiment, a pair of runners  138 ,  140  is provided with the frame. Each one of the runners  138 ,  140  is provided at a corresponding end  136 ,  134  of the frame  112 , adjacent a corresponding one of the end cutting discs  118 ,  126 . Both are made integral to the frame  112  and protrude downwardly from the plane of the cutting discs in a manner that if the frame  112  is lowered too close to the ground, one, or both of the runners  138 ,  140  will come into engaging contact with the ground rather than the cutting discs themselves. 
         [0045]    Although an example embodiment of a brush cutter and its mounting have been illustrated on a road grader, those skilled in the art will understand that a same mounting can be done on a snow plow truck, a front end loader or another road vehicle having wing-plow attachments. Also, a sickle-bar type brush cutter or other brush mower may also be mounted to the wing-plow attachments in a similar way as described herein for providing similar results as those described herein. Finally, it will be noted that in light of the teachings above, a brush cutter can be adapted for other types of mountings, such as a central mounting on a tractor, for instance. Therefore, the above description should not be construed as limiting the scope of the invention.