Abstract:
Lightweight and versatile outboard motors and methods for manufacturing the same from existing motorized lawn implements and lawn implement parts. The outboards consisting essentially of a motor for driving a propeller, an elongate housing creating the body of the outboard, a drive shaft disposed within the elongate housing, and a propeller. The methods involving attaching the motor to the elongate housing and the drive shaft and mounting the propeller to a second end of the elongate housing and drive shaft.

Description:
BACKGROUND 
       [0001]    The present disclosure relates generally to outboard motors (“outboards”) and methods for their manufacture. In particular, outboard motors adapted from existing motorized lawn-care implements and lawn care implement parts are described. 
         [0002]    Known outboard motors are not entirely satisfactory for the range of applications in which they are employed. For example, existing outboards are cumbersome. The weight of a typical outboard makes transport, attachment, detachment, and general use difficult. Standard outboards have a heavy motor and a cast metal casing that add significant weight to the boat and affect the boat&#39;s handling. This is especially true where the outboard is being used with a small vessel. 
         [0003]    The smallest vessels do not typically have the load bearing capacity for an outboard motor. A flat back canoe for example cannot easily support a typical outboard. A canoe relies on a balanced and partially submerged hull for steering and handling. A motor that is too heavy lifts the front of the vessel from the water and diminishes handling and performance. Even conventional trolling outboards and compact design outboards are too heavy. The electric versions require a deep cycle marine battery that, in addition to its substantial weight, requires charging. 
         [0004]    Because compact electric motors require charging, a user is also limited in the distance he may travel on a given charge. A motor that relies solely on a charged battery is inefficient to accomplish consistent, reliable travel of various distances. 
         [0005]    Another limitation created by the weight of existing outboards is the difficulty involved in transporting, attaching, and detaching the motor. Often, a user must remove and re-install the motor for storage, repair, cleaning, or transfer between vessels. Likewise, after removal the motor must be transported. This is not easily accomplished with a standard weight outboard. A lighter motor solves the problems associated with transporting a heavy motor and allows a user to make full use of the outboard without aid. 
         [0006]    In addition to weight limitations, typical outboards are expensive. An outboard adapted from existing inexpensive and readily-available parts would keep sourcing and manufacturing costs low. Additionally, a company currently producing motorized lawn implements and parts would have no need for re-tooling or reorganizing product manufacturing and design if it were to simply adapt existing products into outboards. An outboard motor created from substantially the same materials as an existing lawn implement would minimize overhead costs while increasing a company&#39;s ability to offer a new but related product. This would result in a lower consumer price-point for new outboards, and better price and availability for replacement parts. 
         [0007]    Thus, there exists a need for outboard motors that improve upon and advance the design of known outboards. Examples of new and useful outboards relevant to the needs existing in the field are discussed below. 
       SUMMARY 
       [0008]    The present disclosure is directed to outboard motors and methods of manufacture for outboard motors from existing motorized lawn implements and motorized lawn implement parts. Existing lawn implements and components are modified and adapted to create outboard motors. The conventional lawn-care implement components include a motor attached to an elongate housing that forms the body of the outboard. A flexible drive shaft within the housing couples with the motor on one end and engages a propeller on the opposite end creating an outboard motor. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a side elevation view of a first example of an outboard motor 
           [0010]      FIG. 2  is a perspective view of the outboard motor shown in  FIG. 1  depicting attachment to a small passenger boat 
           [0011]      FIG. 3  is a perspective view of first example of a weed trimmer from which the outboard motor of  FIG. 1  could be manufactured 
           [0012]      FIG. 4  is a flowchart describing a method for manufacturing an outboard motor according to a preferred embodiment of the present invention 
           [0013]      FIG. 5  is a flowchart describing a method for manufacturing an outboard motor according to a preferred embodiment of the present invention 
           [0014]      FIG. 6  is a flowchart describing a method for manufacturing an outboard motor according to a preferred embodiment of the present invention 
           [0015]      FIG. 7  is a flowchart describing a method for manufacturing an outboard motor according to a preferred embodiment of the present invention 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The disclosed outboard motors and methods for their manufacture will become better understood through review of the following detailed description in conjunction with the figures. The detailed description and figures provide merely examples of the various inventions described herein. Those skilled in the art will understand that the disclosed examples may be varied, modified, and altered without departing from the scope of the inventions described herein. Many variations are contemplated for different applications and design considerations; however, for the sake of brevity, each and every contemplated variation is not individually described in the following detailed description. 
         [0017]    Throughout the following detailed description, examples of various outboards are provided. Related features in the examples may be identical, similar, or dissimilar in different examples. For the sake of brevity, related features will not be redundantly explained in each example. Instead, the use of related feature names will cue the reader that the feature with a related feature name may be similar to the related feature in an example explained previously. Features specific to a given sample will be described in that particular example. The reader should understand that a given feature need not be the same or similar to the specific portrayal of a related feature in any given figure or example. 
         [0018]    The outboard motors and methods for manufacture described below include outboards manufactured largely from existing motorized lawn care implements and lawn care implement parts. With reference to  FIGS. 1-3 , a first example of an outboard motor, outboard  100 , will now be described. By way of example only,  FIG. 3  shows a typical motorized weed trimmer  400  from which outboard  100  might be manufactured. Weed trimmer  400  is merely one implement that might be used, in whole or in part, to construct outboard  100 . In yet many other examples outboards may be constructed from an edger, a brush cutter, a tiller, any motorized lawn implement, or their individual components thereto. 
         [0019]    With reference to  FIG. 1 , outboard  100  includes a motor  110 , an output shaft  112 , a flexible drive shaft  130 , an elongate housing  120 , a propeller  140 , a steering control arm  150 , and a transom mounting bracket  160 . Outboard  100  functions to provide a watercraft user (“user”) with a lightweight, inexpensive outboard motor that is fuel efficient and low maintenance. Outboard  100  provides propulsion for am type of watercraft. In particular, outboard  100  is suited to be the sole drive motor for smaller watercraft like canoes, rafts, kayaks, jon boats, and dinghies. 
         [0020]    Additionally outboard  100  can provide auxiliary propulsion or trolling propulsion for larger crafts like sailboats, mid-size fishing boats, and passenger craft. By way of example only,  FIG. 2  shows outboard  100  attached to a small passenger boat. In this example outboard  100  is situated to provide the sole source of propulsion. In yet another example, outboard  100  could be used as secondary propulsion or trolling propulsion by being mounted to the transom next to the primary drive motor. 
         [0021]    The drive power for outboard  100  in  FIGS. 1 and 2  comes from motor  110 . In the instant embodiment motor  110  represents a standard weed trimmer motor as known in the art. Motor  110  is a two-stroke combustion engine using mixed fuel. In another embodiment the motor is a four-stroke combustion engine. In yet other embodiments the motor is a two or four stroke combustion engine utilizing regular fuel or mixed. An embodiment utilizing a diesel motor is also disclosed. 
         [0022]    While some specific embodiments have been listed various further embodiments do not limit the type of motor that can be used for the disclosed outboard and method for manufacture. Any motor commonly known or used in the art sufficient to provide forward propulsion for a given watercraft is contemplated. 
         [0023]    As shown in  FIG. 1 , motor  110  includes output shaft  112 . Output shaft  112  is attached at a first end to motor  110  and at a second end connects to flexible drive shaft  130 . In the present example, the second end of output shaft  112  receives a first end of flexible drive shaft  130 . Output shaft  112  and flexible drive shaft  130  are coupled together with the first end of flexible drive shaft  130  keyed to fit within the second end of output shaft  112 . 
         [0024]    In other embodiments the output shaft and flexible drive shaft are coupled together with coupling methods known in the art. In one example the coupling is accomplished with a threaded first end of the flexible drive shaft and a threaded second end of the output shaft such that both ends may be threaded together. In any embodiment the second end of the output shaft is drivingly connected to the first end of the flexible drive shaft transferring the forward drive of the motor to the flexible drive shaft. 
         [0025]    Turning our attention to flexible drive shaft  130  in  FIG. 1 , we see that the first end of flexible drive shaft  130  drivingly connected to output shaft  112  and a second end drivingly connected to propeller  140 . In this embodiment, flexible drive shaft  130  is a standard weed trimmer drive shaft. In yet other embodiments the flexible drive shaft consists of any shaft known in the art including those from a brush cutter, an edger, or any motorized lawn implement. The coupling of flexible drive shaft  130  to output shaft  112  and the disposal of said shafts within elongate housing  120  resemble a common configuration as found in existing motorized lawn implements. 
         [0026]    Flexible drive shaft  130  has a length that is easily modifiable based upon a given transom height. Since outboard  100  is intended to fit a range of watercraft, the overall length of outboard  100  is preferably modifiable. Flexible drive shaft  130  can be cut to a prescribed length and re-coupled with output shaft  112  and propeller  140 . 
         [0027]      FIG. 1  shows that flexible drive shaft  130  is disposed within elongate housing  120 . Elongate housing  120  is a hollow housing that provides the rigid structure to which most of the individual components of outboard  100  attach. Elongate housing  120  is mounted at a first end to motor  110  so that output shaft  112  and flexible drive shaft  130  are seated within the first end of said housing. A second end of elongate housing  120  is attached to propeller  140  so that the coupling between flexible drive shaft  130  and propeller  140  is seated within the second end of said housing. Both the first and second end of elongate housing  120  are mounted to output shaft  112  and propeller  140  respectively, so that said output shaft, said propeller, and flexible drive shaft  130  are able to spin freely. 
         [0028]    Turning our attention specifically to propeller  140  we find that said propeller is drivingly coupled to flexible drive shaft  130  and mounted to the second end of elongate housing  120  such that said flexible drive shaft and said propeller are able to spin freely. In the instant example propeller  140  is a standard two-blade propeller. In another embodiment the propeller is a three-blade model. In yet other embodiments any currently known or later developed propeller sufficient to provide forward propulsion is contemplated. 
         [0029]    Shifting our attention now to steering control arm  150  in  FIG. 1  we see that said steering control arm includes an attachment collar  152 , a throttle lever  151 , and a motor kill switch  153 . Steering control arm  150  adjustably mounts to elongate housing  120  via attachment collar  152 . In the present example attachment collar  152  is slidingly mounted to elongate housing  120  with the inside diameter of the collar nesting with the outside diameter of the housing. In this and other embodiments a set screw is used to hold the nested portions of the attachment collar and the elongate housing in place. In yet other examples a quick release compression fitting is used. 
         [0030]    Attachment collar  152  is adjustable along the length of elongate housing  120  and in the instant embodiment is set to face towards the interior of a given watercraft.  FIG. 2 , for example, depicts outboard  100  mounted on the transom of a small passenger boat. Steering control arm  150  is shown facing the interior of the boat where a user can easily interface for steering. In the present embodiment steering control arm  150  is used to control the drive direction, speed, and function of outboard  100 . 
         [0031]    The drive direction or steering of outboard  100  is regulated by steering control arm  150 . A user interfacing with steering control arm  150  can move said arm laterally to steer the boat right or left. A user moving the arm toward the right side of the boat (starboard) will steer the boat left. A user moving the arm toward the left side of the boat (port) will steer the boat right. 
         [0032]    The speed of outboard  100  is regulated by the throttle lever  151 . Throttle lever  151  is exemplary of throttles commonly known in the art and regulates the fuel/air mixture entering motor  110 . In the present embodiment, throttle lever  151  is a pull lever mounted towards the terminal end of steering control arm  150 . The more that a given user pulls the throttle lever the faster the motor spins. In another embodiment the throttle lever is a twisting throttle as known in the art. In yet another example, the throttle lever is a push lever throttle as known in the art. 
         [0033]    In the instant example, motor kill switch  153  is mounted to steering control arm  150  at the terminal end near throttle lever  151 . Motor kill switch  153  is a standard kill switch as commonly known in the art. Motor kill switch  153  serves to turn motor function on or off. 
         [0034]    Turning now to transom mounting bracket  160  we see in  FIG. 1  that transom mounting bracket  160  is slidingly attached to elongate housing  120 . Transom mounting bracket  160  is a standard transom mount as known in the art. In the present embodiment transom mounting bracket  160  is adapted to slidingly receive elongate housing  120 . Transom mounting bracket  160  is adjustable along the length of said housing. In every embodiment of the present invention any transom mounting bracket capable of securing outboard  100  to the transom of a given watercraft is contemplated. 
         [0035]    Having described a number of examples for outboard motors we now turn our attention to the methods for their manufacture. The disclosed methods include examples for manufacturing outboards by adapting existing, pre-built motorized lawn implements and also for manufacturing outboards from motorized lawn implement parts. 
         [0036]    With reference to  FIG. 4  a method  200  is described. Method  200  is one example of a method whereby an outboard motor, similar to outboard  100  above, is built from individual motorized lawn implement parts. Method  200  initiates at step  202  by attaching a lawn implement motor, similar to motor  110  disclosed above, to a first end of a lawn implement elongate housing. The elongate housing, similar to elongate housing  120  above, serves to provide a structure to which the outboard components attach. 
         [0037]    Next, at step  204 , a motor output shaft, similar to output shaft  112  above, extending from within the motor is attached to a first end of a flexible drive shaft, similar to flexible drive shaft  130  above, said flexible drive shaft being disposed within the elongate housing. The attachment of the motor output shaft to the flexible drive shaft is accomplished such that the drive from the motor is transferred into the flexible drive shaft. One example of coupling the output shaft and the flexible drive shaft is discussed above in connection with coupling output shaft  112  to flexible drive shaft  130 . The attachment of the motor to the elongate housing, in which the flexible drive shaft is disposed, is accomplished such that said flexible drive shaft and said output shaft are drivingly connected and spin freely within the housing. 
         [0038]    A second end of the flexible drive shaft is coupled to a propeller, similar to propeller  140  above, at step  206  of method  200 . One example of coupling the flexible drive shaft and the propeller is discussed above in connection with coupling flexible drive shaft  130  with propeller  140 . The coupling is accomplished such that the drive output of the motor is transferred to the propeller via the flexible drive shaft. 
         [0039]    Finally, at step  208  a second end of the elongate housing is mounted to the propeller. In the instant method, the second end of the elongate housing is mounted to the propeller in a similar manner as disclosed above. The attachment of the elongate housing to the propeller is accomplished such that the flexible drive shaft and the propeller are able to freely spin independent of the elongate housing. 
         [0040]    Although method  200  is fully disclosed in method steps  202  through  208  additional optional steps may further include shortening the elongate housing, bending the elongate housing, mounting a steering control arm, and attaching a transom mounting bracket. 
         [0041]    With reference to  FIG. 6  optional step  210  introduces shortening the elongate housing. The elongate housing is the structure that determines the overall length of the outboard motor. Because the outboard is meant to be attached to a range of watercraft with varying transom heights and varying distances from the top of the transom to the water, the elongate housing is preferably adaptable within that range. 
         [0042]    The elongate housing, as discussed above, may to be shortened to a selected length prior to attachment to the propeller at step  208 . Outboard  100  disclosed above, for example, utilizes a full length elongate housing. In another embodiment the elongate housing is shortened to fit a smaller transom height. 
         [0043]    Another optional step shown in  FIG. 6  is bending the elongate housing to achieve a desired drive angle at step  212 . Many standard elongate housing examples are unbent or only slightly bent when used as a lawn implement. When the housing is adapted for use in an outboard motor however, a selectable drive angle is desirable. In order to produce forward propulsion the propeller must enter the water and face away from the transom. Bending the elongate housing at an angle similar to that shown in  FIG. 1  increases the ability for the outboard to propel the craft forward. 
         [0044]    In the example disclosed above the drive angle is bent to approximately 90 degrees. In another example the elongate housing is bent to a drive angle of more than 90 degrees. In yet other examples the drive angle is less than 90 degrees. After bending the elongate housing, the flexible drive shaft disposed within the elongate housing automatically bends with the housing. 
         [0045]    Shifting our attention now to optional step  214  of method  200  in  FIG. 6 , mounting a steering control arm is described. Steering control arm serves to steer the outboard. The steering control arm adjustably mounts to elongate housing via an attachment collar similar to that shown in sample outboard  100  discussed above. Attachment collar  152  is slidingly mounted to elongate housing  120  with the inside diameter of the collar nesting with the outside diameter of the housing. In this and other embodiments a set screw is used to hold the nested portions of the attachment collar and the elongate housing in place. In yet other examples a quick release compression fitting is used. In the instant embodiment the steering control arm is set to face towards the interior of a given watercraft.  FIG. 2  for example depicts outboard  100  mounted on the transom of a small passenger boat. Steering control arm  150  is shown facing the interior of the boat where a user can easily interface for steering. 
         [0046]    Turning our attention to attaching a transom mounting bracket at step  216  in  FIG. 6 . The transom mounting bracket contemplated at step  216  is similar to transom mounting bracket  160  disclosed above. Any transom mounting bracket as known in the art capable of attaching an outboard to the transom of a given watercraft is sufficient for step  216 . In the above disclosed embodiment, transom mounting bracket  160  is adapted to slidingly receive elongate housing  120 . Transom mounting bracket  160  is adjustable along the length of said housing. Standard transom mounting brackets known in the art are pre-equipped with attachment means ranging from typical set-screw configurations to quick release adjustable clamps. 
         [0047]    With reference to  FIG. 5 , a method  300  for manufacturing an outboard motor from an existing motorized lawn implement is described. By way of example only, method  300  will be described using a typical motorized weed trimmer  400  from  FIG. 3 . Method  300  is not limited for use to weed trimmer  400  but is useable with any motorized lawn implement. Specific implements include an edger, a brush cutter, or a tiller as commonly known in the art. 
         [0048]    Method  300  begins at step  302  by detaching an existing rotating implement head  401  from a flexible drive shaft. In the present example, rotating implement head  401  is a weed trimming head. Rotating implement head  401  and equivalent structures of other embodiments are detached from the flexible drive shaft and dismounted from a second end of an elongate housing to provide space for installing a propeller. 
         [0049]    Rotating implement head  401  is dismounted from the elongate housing at step  304 . The detaching and dismounting of the existing rotating implement head  401  and equivalent structures in other embodiments is accomplished such that the flexible drive shaft and the elongate housing is prepared to receive the propeller. Existing lawn care implements are designed to have a detachable rotating implement head. The process for removal varies according to the type of implement head. Most implement heads are attached via threaded couplings, set screws, or compression clamps as disclosed above. These heads can simply be unthreaded, unscrewed, or unclamped for removal. 
         [0050]    Next, the flexible drive shaft is coupled with the propeller at step  306 . Propeller coupling is disclosed at length above and requires simply that the flexible drive shaft be drivingly connected to the propeller. The propeller is attached to the elongate housing at step  308 . The coupling and attachment of the flexible drive shaft and the elongate housing to the propeller are accomplished such that the flexible drive shaft and the propeller are drivingly connected and the propeller is able to spin freely. 
         [0051]    Although method  300  is accomplished with steps  302  through  308 , there exist additional optional steps that may be added in the manufacture of outboard motors from existing motorized lawn implements. With reference to  FIG. 7 , steps  310  to  314  describe shortening the elongate housing at step  310 , bending the elongate housing at step  312 , and attaching a transom mounting bracket to the elongate housing at step  314 . Analogous steps for shortening, bending, and attaching a transom mounting bracket to the elongate housing are described at length in method  200  above. 
         [0052]    The disclosure above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in a particular form, the specific embodiments disclosed and illustrated above are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and sub-combinations of the various elements, features, functions and/or properties disclosed above and inherent to those skilled in the art pertaining to such inventions. Where the disclosure or subsequently filed claims recite “a” element, “a first” element, or any such equivalent term, the disclosure or claims should be understood to incorporate one or more such elements, neither requiring nor excluding two or more such elements. 
         [0053]    Applicant reserves the right to submit claims directed to combinations and sub-combinations of the disclosed inventions that are believed to be novel and non-obvious. Inventions embodied in other combinations and sub-combinations of features, functions, elements and/or properties may be claimed through amendment of those claims or presentation of new claims in the present application or in a related application. Such amended or new claims, whether they are directed to the same invention or a different invention and whether they are different, broader, narrower or equal in scope to the original claims, are to be considered within the subject matter of the inventions described herein.