Abstract:
A watercraft propulsion system includes a motor mounted in a container in a water-tight manner. A shaft extends from the motor through the bottom of the container to an impeller disposed in a housing outside the container. The impeller draws fluid into the housing through and opening on the back of the housing to propel a watercraft through the water.

Description:
REFERENCE TO RELATED CASE 
       [0001]    This application claims priority under 35 U.S.C. §119 (e) to provisional application No. 61/773,094, filed on Mar. 5, 2013, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a watercraft propulsion system and a method propelling a watercraft through water. More specifically, the present invention relates to a motorized watercraft that does not use a propeller, allows the user to navigate back water ways, and to be used in areas with as little as six inches of water. 
         [0004]    Many times a paddleboarder or boat operator would like to go into very shallow water to observe wildlife or to pass between bodies of water. Many times, the waterway is too shallow to allow a regular boat with an outboard or inboard motor to pass or is impossible to navigate if a propeller is being used. Also, the shallow water areas may be far from the launch point of the watercraft. So, if a paddleboarder wanted to go to areas where wildlife is, and away from the hustle and bustle of civilization, it may take a long time and a lot of energy for the paddleboarder to get to the destination. Therefore, the current invention allows such a person to motor to the location and then move quietly with the paddles if they so choose. Additionally, the present invention can be used in rescue and military applications where a watercraft with a propeller should not be or can not be used. 
         [0005]    Thus, the present invention allows a person to move a watercraft through shallow water without the need to paddle. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is directed to a watercraft propulsion system that includes a container to hold a motor, the container having an open top, a bottom, and at least one wall extending from the bottom to the open top, the bottom of the container having an opening therethrough, a motor connected to the bottom of the container in a water-tight manner, a shaft operatively connected to the motor extending from the motor through the opening in the bottom of the container, a housing attached to an outside portion of the container, the housing having a bottom surface and a top surface forming a cavity therebetween, the top surface attached to the outside portion of the container and the bottom surface opposite the top surface, the bottom surface having a first opening and being in fluid communication with the cavity, the housing also having a second opening in a side portion of the housing and in fluid communication with the cavity, and an impeller disposed within the cavity of the housing and operatively attached to the shaft, wherein the impeller when in motion draws fluid into the cavity of the housing through the first opening and pushes the fluid out the second opening. 
         [0007]    In some embodiments, the at least one wall comprises 4 walls and is in the shape of a rectangle. 
         [0008]    In some embodiments, the cavity of the housing is generally in the shape of the number nine. 
         [0009]    In some embodiments, the watercraft is selected from the group of a paddleboard, a canoe, a jon boat, and a surf board. 
         [0010]    In yet another aspect, the present invention is directed to a watercraft having a watercraft propulsion system that includes a watercraft having a hull and an opening therein, a container to hold a motor, the container having an open top, a bottom, and at least one wall extending from the bottom to the open top, the bottom of the container having an opening there through, the at least one wall of the container extending above the opening in the hull and the bottom of the container being generally flush with a bottom surface thereof, a motor connected to the bottom of the container in a water-tight manner, a shaft operatively connected to the motor extending from the motor through the opening in the bottom of the container, a housing attached to an outside portion of the container, the housing having a bottom surface and a top surface forming a cavity therebetween, the top surface attached to the outside portion of the container and the bottom surface on an opposite of the housing, the bottom surface having a first opening and being in fluid communication with the cavity, the housing also having a second opening in a side portion of the housing and in fluid communication with the cavity, and an impeller disposed within the cavity of the housing and operatively attached to the shaft, wherein the impeller when in motion draws fluid into the cavity of the housing through the first opening and pushes the fluid out the second opening. 
         [0011]    Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein, including the detailed description which follows, the claims, as well as the appended drawings. 
         [0012]    It is to be understood that both the foregoing general description and the following detailed description of the present embodiments of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the invention and, together with the description, serve to explain the principles and operations of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of one embodiment of a watercraft propulsion system according to the present invention; 
           [0014]      FIG. 2  is an exploded, perspective view of the watercraft propulsion system of  FIG. 1  in reference to a watercraft; 
           [0015]      FIG. 3  is a top perspective view of a container of the watercraft propulsion system of  FIG. 1 ; 
           [0016]      FIG. 4  is a bottom perspective view of the watercraft propulsion system of  FIG. 1  illustrating the housing attached to the container; 
           [0017]      FIG. 5  a bottom perspective view of the watercraft propulsion system of  FIG. 1  illustrating the housing attached to the container with the housing having the bottom surface removed to show the impeller and the cavity; 
           [0018]      FIG. 6  is a top perspective view of the housing; and 
           [0019]      FIG. 7  is an elevational view illustrating the flow of a liquid through the housing during operation of the watercraft propulsion system. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]    Reference will now be made in detail to the present preferred embodiment(s) of the invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. 
         [0021]    One embodiment of a watercraft propulsion system  10  is illustrated in the figures. Referring to  FIGS. 1 and 2 , the watercraft propulsion system  10  has a motor  12 , a shaft  14  extending from the motor  12  through a motor mount  16 . The motor mount  16  in turn is secured to a container  18 . The container  18  is mounted to the watercraft  100  through a hole  102  as seen in  FIG. 2 . Preferably, the hole  102  is about two thirds of the way back in the watercraft  100 , although it could be placed anywhere in the watercraft  100  and still fall within the scope of the present invention. An impeller  20  is connected to the shaft  14  and is disposed in the housing  22 . As seen in  FIG. 3 , the container  18  has an opening  24  that allows the impeller  20  to pass therethrough even if the impeller  20  is attached to the shaft  14 . 
         [0022]    The motor  12  as illustrated in the figures is a representation of a motor generally, which is preferably a small gasoline-type engine. More particularly, the motor  12  is a one horsepower engine that has 25 cc displacement. A Honda GX35 engine was used and allows many miles of travel on less than a quart of fuel. However, any type of motor would work, e.g., electric, diesel, or gasoline, and would fall within the scope of the present invention. Additionally, a larger or smaller motor may also be substituted, depending on the usage, the person riding the watercraft  100 , the size of the watercraft  100 , and the speed at which the rider would like to travel. 
         [0023]    In this embodiment, the clutch was removed from the off-the-shelf motor  12  and the shaft  14  was attached to the motor  12 . The shaft  14  has a back end  30  that is configured to attach to the motor  12 . In the present embodiment, that means a large discus-shaped back end  30 . On the other side of the shaft  14  is a smaller, elongated portion  32  that protrudes through the motor mount  16  and attaches to the impeller  20 . The elongated portion  32  of the shaft  14  is about ¾″ in diameter, but other sizes and shapes could be used. 
         [0024]    The motor  12  is preferably mounted to a motor mount  16 . The motor mount  16  is flat and preferably machined from aluminum to accommodate several features. First, the opening  34  of the motor mount  16  allows the front portion  32  of the shaft  14  to pass therethrough. Preferably, although known to those in the art, the opening  34  would have a seal  36  to seal the opening  34  and not allow water to enter into the container  18 , where it could damage the motor  12 . Holes  38  are used in attaching the motor  12  thereto and holes  40  are used in attaching the motor mount  16  to the container  18 . A raised ring  42  is preferably machined into the motor mount  16  and would fit between the back end  30  of the shaft  14  and the housing on the motor  12 . 
         [0025]    The container  18  is illustrated as a square box that is sufficiently large enough to fit the motor  12  and allow for access to the motor mount  16  to secure it into the container  18 . A container  18  that is 12″×12″ has been determined to be sufficiently large to allow the motor noted above to fit comfortably therein. This size also fits well in the hulls of most watercraft. The container  18  has an open top  44  and a bottom  46 , with bottom  46  having the opening  24 . The container  18  also has at least one wall  48  that extends from the open top  44  to the bottom  46 . Thus, the container  18  (and probably also the motor mount  16 ) may be circular and still fall within scope of the current invention. As illustrated in the figures, the container  18  is a square, but may also be a rectangle or another shape as desired. The container  18  is secured within the opening  102  in the watercraft  100  in any appropriate manner. Obviously the container  18  needs to be secure, but also sealed around the bottom  46  and the top of the hull of the watercraft  100 . 
         [0026]    The opening  24  in the container  18  is preferably large enough to allow impeller  20  to pass therethrough. This allows the removal of the motor  12  and motor mount  16  from the container  18  without having to first remove the housing  22  and the impeller  20 . However, the opening  24  could be smaller than the impeller  20  if so desired. While not illustrated, a gasket or other water sealing device is naturally placed around the opening  24  of the container  18  so that when the motor mount  16  is secured to container  18 , the opening  24  is sealed and water does not get into the container  18  and damage the motor  12 . One of ordinary skill in the art would know the type (e.g., neoprene, rubber, etc.) and size to use. 
         [0027]    The impeller  20  is secured to the shaft  14  in any appropriate manner. In the present invention, there is an opening  50  that allows a screw or rivet to be used to secure the impeller  20  to the shaft  14 . The impeller  20  is a three inch four-bladed impeller by Flo-Tech, but any appropriate impeller or size of impeller can be used and come within the scope of the present invention. 
         [0028]    The housing  22  is attached to the bottom  46  of the container  18  as illustrated in  FIG. 4 . The manner of attachment is not important, but is done in the present embodiment with screws into the bottom  46  through holes  52  on the housing  22 . While the housing  22  does not have to be sealed tightly against the bottom  46  of the container  18 , it is preferably. 
         [0029]    Referring to  FIGS. 5 and 6 , housing  22  has a top surface  54  and a bottom surface  56 , illustrated in  FIG. 2  as a separate piece  56   a.  However, it should be noted that the housing  22  can be milled as a single, unitary piece from a single piece of aluminum. The top surface  54  and the bottom surface  56  or piece  56   a  form a cavity  58  in the housing  22 . The cavity  58  is illustrated as being in the shape that generally approximates a figure nine or even a six depending on the point of view. See  FIG. 6 . The bottom surface  56  or piece  56   a  of housing  22  has a first opening  60  that is aligned with the center of the impeller  22 . See  FIGS. 4 and 5 . The first opening  60  acts as an inlet for the watercraft propulsion system  10  as explained in more detail below. The housing  22  has a second opening  62  that acts as an outlet for the watercraft propulsion system  10 . A screen can be attached to the housing  22  to prevent weeds, trash, and other debris from entering the cavity  58  and interfering with the impeller  20  or clogging the housing  22 . As best seen in  FIGS. 5 and 6 , the second opening  62  is in a side portion  64  of the housing  22 . The housing  22  is preferably made from milled aluminum but could be made from any appropriate material. Naturally, the lighter the material used in all of the watercraft propulsion system  10 , the smaller the motor  12  is needed for the same watercraft  100 . It should be noted that the housing  22  has a height of about one inch. This allows the watercraft  100  with the watercraft propulsion system  10  to move through shallow water. Many of the boards (both paddle and surf) have fins on them that are somewhere between two and four inches, and therefore, the height of the housing  22  is less, allowing safe passage in as little as six inches of water. 
         [0030]    When the motor  12  is operating, the impeller  20  spins in a counter clockwise direction when viewed from the bottom of the watercraft propulsion system  10 . This causes the water in which the watercraft with the watercraft propulsion system  10  is sitting to be drawn into the housing  22 , and the cavity  58  in particular, as illustrated by the arrows A in  FIG. 7 . The water, being moved at a relatively high rate, then passes through the cavity  58  and out the second opening  62  of the housing  22  and rearwardly relative to the watercraft  100  as illustrated by the arrows B. This thrust from the housing  22  in turn causes the watercraft to move forward in the water. 
         [0031]    The operator of watercraft propulsion system  10  preferably has controls attached to the container  18  that allow the operator to control the speed of the motor  12 , and thus the speed of the watercraft  100 , can be easily accessed using the paddle. Alternatively, the controls could be attached directly to the watercraft  100  and allow for the operator to use his/her foot to control the speed or by a hand control. A quick shut off or kill switch as is known in the art is also preferable in the event of an emergency or the operator falls off of or out of the watercraft  100 , as the case may be. 
         [0032]    It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention. Thus it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.