Abstract:
A vegetation cutter attachment system for a trolling motor to aid in cutting water weeds and grass that wrap around the propeller or motor housing of the trolling motor during use. The attachment system includes a plate affixable to the motor housing and conformed to the motor housing&#39;s shape and at least one corner with a cutting surface.

Description:
FIELD OF THE INVENTION 
     The present invention is, generally, an improvement on trolling motors, and specifically, a vegetation cutter for a trolling motor to cut away vegetation, such as grass, weeds and other aquatic vegetation, and trolling motors with an integral vegetation cutter. 
     BACKGROUND 
     A trolling motor is a self-contained unit that includes an electric motor, propeller and controls, and is affixed to a boat, either at the bow or stern. Trolling motors are often used by anglers, such as bass fishermen, who want their boat to slowly move around an area, or to maintain their position, while they cast their lures. A trolling motor is usually a secondary means of propulsion mounted on the transom alongside the watercraft&#39;s primary outboard motor. However, a trolling motor may be the primary source of propulsion for smaller watercraft, such as canoes and kayaks, and on lakes where the use of a gasoline-powered engine is prohibited. 
       FIG. 1  illustrates a prior art clamp mounted trolling motor that is adapted for removably mounting to a watercraft. The motor  10  is attached to a propeller  12  by propeller shaft (See Ref.  70  in  FIG. 3C ) which extends from the back portion of the motor housing  24 . A skeg  14 , which is a rudder or fin for the motor  10 , extends from the bottom of the motor housing  24  and a shaft  16  extends from the top of the motor housing  24 . A clamp  18  is provided for clamping the assembly onto the watercraft and for adjusting the position of the shaft  16 . At the top of the shaft  16  is the tiller  20  and controls  22  for steering and operating the assembly, respectively. Other trolling motors are adapted for permanent mounting on the bow of a watercraft, such as a bass boat. These motors replace the clamp  18  of the motor  10  of  FIG. 1  with a mounting assembly and often include a foot pedal that allows the motor to be controlled by the user&#39;s foot. One of ordinary skill in the art will recognize that many variations may be made on this basic design for a trolling motor and the present invention should not be seen as being limited to any specific style of trolling motor. 
     All trolling motor users are familiar with the perpetual problem of grasses, weeds, lily pads, or other aquatic vegetation, getting wound around the propeller or shaft of trolling motors. Following this, in the best of scenarios, the trolling motor loses efficiency. If this vegetation gets too wound around the propeller, it becomes necessary to stop the motor, remove it from the water, and remove the vegetation. Not only is this a nuisance, but as the propeller and/or skeg may be sharp, the user is in danger of cutting himself during the removal process. In addition, damage may be caused to the seals around the propeller shaft, which keep water from coming into contact with the electric motor, thus necessitating major repair of the trolling motor. In other circumstances, the stuck vegetation may cause the propeller to stop rotating completely; sometimes called “shorting” the trolling motor. Such a short may cause temporary or permanent damage to the motor. In addition, if the trolling motor is the watercraft&#39;s primary outboard motor, then the trolling motor user is stuck in place. If the trolling motor is the watercraft&#39;s secondary outboard motor, the user may be forced to use the primary gasoline-powered motor, which will likely end his fishing for the day, and may be illegal, depending on where he is. Therefore there is a need to prevent the buildup of aquatic vegetation around the propeller of trolling motors. 
     This need was the object of U.S. Pat. No. 4,911,664 to Gremillion. This invention discloses a weed cutting and shredding attachment for an electric trolling motor including a sharpened cutting blade oriented with the sharp edge thereof adjacent to the path of the movement of the leading edge of the propeller blades on an electric trolling motor together with a mounting structure for effectively mounting the cutting element from the trolling motor. The attachment includes a cutting element or blade, provided with a bracket structure for detachably and removably securing the attachment to the trolling motor. 
     Although this invention discloses one manner in which to address the problem, this device had several drawbacks that prevented it from being commercially successful. First, this attachment extended outward from the skeg and forward of the intersection between the propeller and the motor housing, which renders it ineffective at cutting vegetation that has wrapped itself around the rear portion of the propeller. Second, because its sharp blade extends outward from the skeg, it creates a serious safety hazard. Third, the design requires that the device be mechanically fastened to the skeg, preferably by drilling and tapping a hole in the skeg and screwing it in place. This drilling and tapping is undesirable. It often causes the motor&#39;s warranty to be voided and, should the mechanical fastener loosen, it can contact the propeller, causing damage and, potentially shorting. In addition, as the mechanical fastener loosens, it renders the device ineffective and prone to loss. Fourth, as the attachment protrudes out and down between the propeller and skeg, the cutting element may simply end up being another protrusion around which vegetation may wind, which is especially true as the cutting element dulls. Finally, the device is not adapted for manufacturing as part of the motor itself, which relegates the device to the aftermarket. Therefore, there is ample room for improvement over this invention. 
     Another attempt to address the problem of the winding vegetation is to add a sharpened blade, such as a metal blade, to the skeg of the trolling motor, so that the skeg is extended to be quite close to the propeller, and also sharpened. Although this model may have some success, it also has its drawbacks. First, it will affect the watercraft&#39;s steering by making the rudder effectively larger. The person steering the watercraft will have to accommodate himself to the change, as smaller moves may result in larger changes in direction. In addition, the attachment, which is usually secured with screws through the skeg will make the skeg less fluidly dynamic, again affecting the steering of the watercraft. Moreover, the sharp edge is a serious safety hazard and, as the sharp edge of the skeg attachment dulls, the attachment will only serve to decrease the space between the skeg and the propeller so that there is less space for vegetation to travel naturally therethrough, thus creating greater and more severe blockages. 
     Therefore, there is a need a device that is effective at cutting vegetation that has wrapped itself around the rear portion of the propeller, that does not extend outward from the skeg, that does not creates a serious safety hazard, that does not need be mechanically fastened to the skeg, that will not cause the motor&#39;s warranty to be voided, that will not be prone to contacting the propeller, that is not prone to loss, that may be integrated into the motor housing, and that will not result in the cutting element being another protrusion around which vegetation may wind. 
     SUMMARY OF THE INVENTION 
     The present invention is an attachment system for a trolling motor and a trolling motor including the attachment of the present invention. 
     The attachment system of the present invention is for use with any standard trolling motor, such as that shown in  FIG. 1  and described above. The attachment system includes a plate, which includes a bottom surface that may be affixed to the motor housing of the trolling motor, and a means for affixing the plate to the motor housing. The preferred means of affixation is with epoxy, and the plate preferably includes one or more holes through the plate through which the epoxy is capable of flowing for better adhesion. However, mechanical means, such as screws, clamps or the like may also be sued. The plate has a right side and a left side and at least one corner with a cutting surface. 
     In some embodiments, both corners on a side may include cutting surfaces, or an entire side may include a cutting surface. In still others, the cutting surface is a removable cutting surface that is attached to the plate by a screw or other mechanical means and may be replaced when dull. 
     The plate is curved and contoured to conform to the shape of the motor housing. All motor housings are cylindrical, so the preferred plate for use with a standard motor housing is also rounded for flush affixation of the plate to the round motor housing. The preferred plate is rectangular when flattened meaning that, were the curve eliminated, the plate would be form a rectangular prism. The preferred plate has a width of between 2.25 and 2.75″, preferably approximately 2.5″; a length of between 1.5 and 2″, preferably approximately 1.75″; and a height of between 1/16 and 3/16″, preferably ⅛″. The plate includes a motor housing side that will be flush against the motor housing when installed, and a top surface that will face away from the motor housing when installed. The cutting surface slopes downward through the height so that the thickest part of the cutting surface is proximate to the top surface and the thinnest part of the cutting surface is proximate to the motor housing side. 
     The plate is preferably made of aluminum, which is preferred due to the fact that it is non-magnetic and will not interfere with the operation of the motor, as well as its corrosion resistance. However, other materials, such as plastics or composites may provide similar properties, and ferrous metals, such as steels, may be used provided the motor housing provides adequate magnetic shielding. 
     The trolling motor of the present invention is a trolling motor commonly used in the art with the vegetation cutter attachment either affixed to the motor housing of the trolling motor using the attachment means, as discussed above, or with the cutting surface formed integral to the housing of the trolling motor. In embodiments in which the vegetation cutter attachment is affixed to the motor housing, the plate is attached to the cylindrical back portion of the motor housing of the trolling motor proximate to said propeller such that the cutting surface is exposed and positioned to cut said vegetation from said propeller. In embodiments in which the cutter is formed integral to the housing, the motor housing includes an extension that may either be sharpened or allow for mounting of a sharpened blade thereto. 
     It is preferred that the plate be disposed away from the skeg and between the propeller and the shaft, preferably at a ninety degree position between the top and the skeg. When the trolling motor is in operation, the movement of the propeller will create a spiral slipstream that moves around the motor housing. The spiral slipstream will move water and vegetation around the motor housing in this direction as well. The direction of the spiral slipstream “engages” the left side of the plate, including the left propeller facing corner. That is to say that the spiral slipstream will move over that left side, including the left propeller facing corner from the bottom of the plate to the top of the plate. On the right side of the plate, the spiral slipstream will “glide” over the right side and its corners, meaning the spiral slipstream will move over the side from the top of the plate to the bottom of the plate. The engagement of spiral slipstream with the left side of plate, and especially the left propeller facing corner, will bring vegetation, such as weeds, grass, and fishing line, across the left side and its left propeller facing corner. When the vegetation moves across the left propeller facing corner with the cutting surface, the vegetation will be cut before it has a chance to wind around the trolling motor. 
     Therefore, it is an aspect of the invention to provide a vegetation cutter device that is effective at cutting vegetation that has wrapped itself around the rear portion of the propeller. 
     It is a further aspect of the invention to provide a vegetation cutter device that does not extend outward from the skeg. 
     It is a further aspect of the invention to provide a vegetation cutter device that does not creates a serious safety hazard. 
     It is a further aspect of the invention to provide a vegetation cutter device that does not need be mechanically fastened to the skeg. 
     It is a further aspect of the invention to provide a vegetation cutter device that will not cause the motor&#39;s warranty to be voided. 
     It is a further aspect of the invention to provide a vegetation cutter device that will not be prone to contacting the propeller. 
     It is a further aspect of the invention to provide a vegetation cutter device that is not prone to loss. 
     It is a further aspect of the invention to provide a vegetation cutter device that may be integrated into the motor housing. 
     It is a still further aspect of the invention to provide a vegetation cutter device that will not result in the cutting element being another protrusion around which vegetation may wind. 
     These aspects of the present invention are not meant to be exclusive and other features, aspects, and advantages of the present invention will be readily apparent to those of ordinary skill in the art when read in conjunction with the following description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a prior art silhouette of a prior art clamp mounted trolling motor. 
         FIG. 2A  is a partial side view of a trolling motor to which the vegetation cutter attachment of the present invention is affixed. 
         FIG. 2B  is a partial perspective view of the trolling motor of  FIG. 2A . 
         FIG. 3A  is a top view of the preferred plate of the vegetation cutter attachment system of the present invention. 
         FIG. 3B  is a side view of the plate of  FIG. 3A . 
         FIG. 3C  is a rear view of the trolling motor of  FIG. 3A  with the propeller removed showing the vegetation cutter attachment affixed to the substantially cylindrical motor housing of the trolling motor. 
         FIG. 4  is a top view of an alternative embodiment of the plate of the vegetation cutter attachment system of the present invention having two cutting surfaces. 
         FIG. 5A  is a top view of an alternative embodiment of the plate of the vegetation cutter attachment system of the present invention in which a removable blade is used as the cutting surface. 
         FIG. 5B  is a side view of the plate of  FIG. 5A   
         FIG. 6  is a perspective view of an embodiment of the trolling motor of the present invention in which the cutting surface is formed as part of the motor housing. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 2A and 2B , focus on the lower portion of trolling motor  10 , specifically the portion at the bottom of shaft  16  including motor housing  24 , propeller  12 , and skeg  14 . It is understood that the remainder of trolling motor  10 , including tiller  20  and clamp  18 , as illustrated in  FIG. 1 , are also included in the trolling motor  10  of the present invention, but are not shown for the sake of clarity in focusing on the lower portion. It is further understood than any trolling motor  10  commonly known in the art may be used in connection with this invention. 
     Referring first to  FIGS. 2A and 2B , side and perspective views of trolling motor  10  of the present invention are provided, respectively. The motor housing  24  of trolling motor  10  has a substantially cylindrical shape  30 . Cutter attachment system  26  includes plate  28  having a bottom surface (shown as  46  in  FIG. 3B ) affixed to the top of motor housing  24  away from skeg  14  and between propeller  12  and shaft  16 . This area often becomes wound with weeds, so it is the logical place for the plate  28 . Although it is shown directly on top of motor housing  24 , the preferred disposition is on the side substantially equidistant from the skeg  14  and the top of the motor housing  24 , as is shown in  FIG. 3C . 
     Plate  28  includes at least one corner, such as left propeller facing corner  32 , which includes a cutting surface  40 . The cutting surface  40  is preferably achieved by grinding the area between corner  32  and the inside end  33  of the cutting edge  42  down to form a sharp cutting edge  42 , but any means of creating such a cutting edge  42  that is commonly used in the art may be substituted. Further, as shown in  FIGS. 5A and 5B , the area between corner  32  and inside end  33  may be dimensioned as a holder for a replaceable removable blade having a cutting surface  40 . The cutting surface  40  is positioned such that it extends beyond the back portion of the motor housing  24  such that it does not interfere with the propeller  12 . 
     When trolling motor  10  is in operation, the movement of propeller  12  will create a spiral slipstream  58  that moves around motor housing  24  in the direction shown in  FIG. 2A . The spiral slipstream  58  will move water and vegetation around motor housing  24  in this direction as well. The direction of the spiral slipstream  58  “engages” the left side  60  of plate  28 , including left propeller facing corner  32 . That is to say that the spiral slipstream  58  will move over that left side  60 , including left propeller facing corner  32  from the bottom of the plate  28  to the top of the plate  28 . On the right side  62  of the plate  28  (shown in  FIG. 2B ), the spiral slipstream  58  will “glide” over the right side  62  and its corners, meaning the spiral slipstream  58  will move over the side from the top of the plate  28  to the bottom of the plate  28 . The engagement of spiral slipstream  58  with the left side  60  of plate  28 , and especially left propeller facing corner  32 , will bring vegetation, such as weeds, grass, and fishing line, across left side  60  and left propeller facing corner  32 . When the vegetation moves across left propeller facing corner  32  with cutting surface  40 , the vegetation will be cut before it has a chance to wind around the trolling motor  10 . 
     It is understood that left and right sides and the direction of the spiral slipstream  58  are arbitrary. The direction of the spiral slipstream  58  will change depending on whether the propeller  12  is able to spin in both directions. The orientation shown herein is standard, but it is understood that if the propeller  12  spun in the other direction, then the direction of the spiral slipstream  58  would also be reversed. As shown in  FIG. 4 , in embodiments adapted for use with trolling motors  10  having reversible propellers  12 , the opposite corner  36  may also include a cutting surface  40  to allow vegetation to be cut when the propeller moves in the opposite direction. However, as the propeller  12  itself will typically cut vegetation, this embodiment is not preferred. 
     The vegetation cutter attachment system  26  includes attachment means for attaching the plate  28  to the motor housing  24 . These means may be any means commonly used in the art that would not compromise the operation of the trolling motor  10 , specifically the motor being housed within the motor housing  24 . Although watertight screws could be used, for example, for the reasons described above with regard to the Gremillion patent, it is preferred that the attachment means be epoxy (not shown), specifically A/B epoxy. As epoxy is the preferred attachment means, it is also preferred that plate  28  include at least one hole  56 . Holes  56  allow the epoxy to flow through the plate  28  for better adhesion. The holes  56  are preferably multiple round holes  56 , as shown in  FIG. 3 , but may be oblong shaped, such as the rectangular hole shown in  FIG. 4 , or any other desired shape. However, in some embodiments in which epoxy is the attachment means, the bottom surface  46  may include slots, such as sots  78  shown in  FIG. 5B , grooves or other means for enhancing adhesion between the bottom surface  46  and the motor housing  24 . 
     Now referring to  FIGS. 3A and 3B , the plate  28  is shown in top and side views respectively. Plate  28  preferably has a width  52  of between 2.25 and 2.75″, preferably approximately 2.5″; a length  54  of between 1.5 and 2″, preferably approximately 1.75″; and a height  50  of between 1/16 and 3/16″, preferably ⅛″. Plate  28  includes left propeller facing corner  32 , left shaft facing corner  34 , right propeller facing corner  36 , and right shaft facing corner  38 . At least one corner, preferable left propeller facing corner  32 , includes cutting surface  40 , as described above. Plate  28  also includes bottom surface  46 , which is flush to motor housing  24  when plate  28  is attached to motor housing  24 , and top surface  48 , which faces away from motor housing  24  when plate  28  is attached to motor housing  24 . Cutting surface  40  is cut through height  50  on a slope from top surface  48  down to bottom surface  46 , so that the thickest section  44  of cutting surface  40  is near or adjacent to top surface  48  and the cutting edge  42 , which is the thinnest area of cutting surface  40 , is near or adjacent to bottom surface  46 . The plate is curved and contoured to conform to the shape of the motor housing. All motor housings are cylindrical, so the preferred plate for use with a standard motor housing is also rounded for flush affixation of the plate to the round motor housing. The preferred plate  28  is rectangular when flattened meaning that, were the curve eliminated, the plate  28  would be form a rectangular prism. However, the plate may take other shapes. 
     The plate  28  is preferably made of aluminum, which is preferred due to the fact that it is non-magnetic and will not interfere with the operation of the motor, as well as its corrosion resistance. However, the plate  28  may be made from other materials, such as plastics or composites, which provide similar properties. Further, although not preferred, ferrous metals, such as steels, may be used provided the motor housing  24  provides adequate magnetic shielding to avoid interference with the operation of the motor  10 . 
     Referring now to  FIGS. 5A and 5B , in some embodiments of the invention, the plate  28  includes a removable blade  74  having a cutting surface  40 . As shown in  FIGS. 5A and 5B , the blade  74  may be attached via a screw  76  that mates with a tapped opening (not shown) in the plate  28 . However, other embodiments may utilize clamps or other art recognized means for attaching a blade to a holder. 
       FIG. 6  shows one embodiment of the trolling motor  10  in which the cutting surface  40  is formed integral to the motor housing  24 . In such embodiments, the plate  28  is eliminated and the cutting surface  40  is formed during the manufacturing process. Alternatively, the motor housing  24  may be adapted to accept a removable blade, such as the blade  74  shown in  FIGS. 5A and 5B . 
     Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions would be readily apparent to those of ordinary skill in the art. Therefore, the spirit and scope of the description should not be limited to the description of the preferred versions contained herein.