Patent Publication Number: US-11643168-B1

Title: Through-hull passive inboard hydro-generator for a marine vessel

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to electric generators, and, more particularly, relates to a passive hydro-powered generator system for marine applications. 
     BACKGROUND OF THE INVENTION 
     Many marine vessels use electric power for a variety of applications, including, for example, electronic navigation systems, sonar systems for depth/fish finding, climate control systems, engine starting, engine lift, trim systems, and so on. Further, there are also electrical motor used on vessels that range from conventional trolling motors to the main propulsion system. Battery systems are used to provide a reservoir of electric power, and in more sophisticated vessels, particularly those with in-board motor systems, a generator can provided to recharge the battery. Typically the in-board propulsion system is an internal combustion engine that can drive a generator system as well as a propeller. Alternatively, electric motors can be used as the main propulsion system. Vessels outfitted for live-aboard conditions may include a separate generator, as well as solar panels, wind-driven generators, and/or towed or transom mounted hydro generators that can be used to replenish charge in the vessel&#39;s battery system. However these systems can be cumbersome to install and maintain. 
     Therefore, a need exists to overcome the problems with the prior art as discussed above. 
     SUMMARY OF THE INVENTION 
     In accordance with some embodiments of the inventive disclosure, there is provided a passive marine electrical generator that includes an intake manifold that has an opening. The opening has an area, and a wall surrounding the opening that extends upward from the opening and reduces to an intake manifold exit that is positioned over a rear of the opening. There is further included a funnel member coupled to the intake manifold exit that reduces from the intake manifold exit and that extends upwards and to the rear of the intake manifold to a funnel member exit. The generator system further includes a conduit having a first portion coupled to the funnel member exit, where the first portion extends further upward and to the rear of the intake manifold to an elbow transition, and then to a second portion which extends horizontally in a direction away from the intake manifold to a conduit exit. The passive marine generator system further includes an impeller disposed in the first portion of the conduit proximate to the funnel exit, and a shaft coupled to a center of the impeller at a first end of the shaft, the shaft extends from the impeller upward along the first portion of the conduit and through a sealed opening in a top of the elbow transition. A generator is mounted on top of the conduit and is coupled to a second end of the shaft. 
     In accordance with a further feature, the first portion of the conduit is angled at forty degrees relative to the opening of the intake manifold, with a range of +/−five degrees. 
     In accordance with a further feature, the opening of the intake manifold has a front edge and sides extending from the front edge to a point at a back of the opening. 
     In accordance with a further feature, the intake manifold opening has a five sided shape including a rectangular portion comprised of the front edge and having parallel opposing sides that extend towards the back of the opening to a triangular portion having sides that meet at the point centrally at the back of the opening. 
     In accordance with a further feature, the point at the back of the opening is positioned behind the funnel portion. 
     In accordance with a further feature, the parallel opposing sides extend from the front edge to halfway to the back of the opening. 
     In accordance with a further feature, there is further included a screen over the opening of the intake manifold. 
     In accordance with a further feature, the conduit exit is positioned to be above a resting water line. 
     In accordance with a further feature, the intake manifold has a top wall that extends at an angle from the front edge toward the intake funnel, wherein the top wall becomes rounded from in a direction parallel to the front edge where it meets the intake funnel. 
     In accordance with a further feature, there is further included a battery controller, a first battery bank, a second battery bank, and the charge controller is configured to switch connections of the first and second battery to the generator based on a charge state of the first and second battery banks. 
     In accordance with some embodiments of the inventive disclosure, there is provided a marine vessel that includes a hull having a bottom and a transom at a rear of the hull. The marine vessel further includes an intake manifold mounted at the bottom of the hull and which has an opening co-located over an opening in the hull. The opening of the intake manifold has an area, and a wall surrounding the opening of the intake manifold that extends upward from the opening of the intake manifold and which reduces in area to an intake manifold exit that is positioned over a rear of the opening of the intake manifold. The vessel further includes a funnel member coupled to the intake manifold exit that reduces in area from the intake manifold exit that extends upwards and to the rear of the intake manifold to a funnel member exit. The vessel further includes a conduit having a first portion coupled to the funnel member exit which extends further upward and to the rear of the intake manifold to an elbow transition and then to a second portion which extend horizontally to the rear and in a direction away from the intake manifold to a conduit exit at the transom of the hull. The vessel further has an impeller disposed in the first portion of the conduit proximate to the funnel exit, a shaft coupled to a center of the impeller at a first end of the shaft, the shaft extends from the impeller upward along the first portion of the conduit and through a sealed opening in a top of the elbow transition, and a generator mounted on top of the conduit that is coupled to a second end of the shaft. 
     In accordance with a further feature, the first portion of the conduit is angled at forty degrees relative to the opening of the intake manifold. 
     In accordance with a further feature, the opening of the intake manifold has a front edge and sides extending from the front edge to a point at a back of the opening. 
     In accordance with a further feature, the intake manifold opening has a five sided shape including a rectangular portion comprised of the front edge and having parallel opposing sides that extend towards the back of the opening to a triangular portion having sides that meet at the point centrally at the back of the opening. 
     In accordance with a further feature, the point at the back of the opening is positioned behind the funnel portion. 
     In accordance with a further feature, the parallel opposing sides extend from the front edge to halfway to the back of the opening. 
     In accordance with a further feature, there is further included a screen over the opening of the intake manifold. 
     In accordance with a further feature, the conduit exit is positioned to be above a resting water line. 
     In accordance with a further feature, the intake manifold has a top wall that extends at an angle from the front edge toward the intake funnel, wherein the top wall becomes rounded from in a direction parallel to the front edge where it meets the intake funnel. 
     In accordance with a further feature, there is further included a battery controller, a first battery bank, a second battery bank, and the charge controller is configured to switch connections of the first and second battery to the generator based on a charge state of the first and second battery banks. 
     Although the invention is illustrated and described herein as embodied in a through-hull passive mariner generator system, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. Additionally, well-known elements of exemplary embodiments of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention. 
     Other features that are considered as characteristic for the invention are set forth in the appended claims. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one of ordinary skill in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention. While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward. The figures of the drawings are not drawn to scale. 
     Before the present invention is disclosed and described, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The terms “a” or “an,” as used herein, are defined as one or more than one. The term “plurality,” as used herein, is defined as two or more than two. The term “another,” as used herein, is defined as at least a second or more. The terms “including” and/or “having,” as used herein, are defined as comprising (i.e., open language). The term “coupled,” as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically. The term “providing” is defined herein in its broadest sense, e.g., bringing/coming into physical existence, making available, and/or supplying to someone or something, in whole or in multiple parts at once or over a period of time. 
     “In the description of the embodiments of the present invention, unless otherwise specified, azimuth or positional relationships indicated by terms such as “up”, “down”, “left”, “right”, “inside”, “outside”, “front”, “back”, “head”, “tail” and so on, are azimuth or positional relationships based on the drawings, which are only to facilitate description of the embodiments of the present invention and simplify the description, but not to indicate or imply that the devices or components must have a specific azimuth, or be constructed or operated in the specific azimuth, which thus cannot be understood as a limitation to the embodiments of the present invention. Furthermore, terms such as “first”, “second”, “third” and so on are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance. 
     In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly defined and limited, terms such as “installed”, “coupled”, “connected” should be broadly interpreted, for example, it may be fixedly connected, or may be detachably connected, or integrally connected; it may be mechanically connected, or may be electrically connected; it may be directly connected, or may be indirectly connected via an intermediate medium. As used herein, the terms “about” or “approximately” apply to all numeric values, whether or not explicitly indicated. These terms generally refer to a range of numbers that one of skill in the art would consider equivalent to the recited values (i.e., having the same function or result). In many instances these terms may include numbers that are rounded to the nearest significant figure. In this document, the term “longitudinal” should be understood to mean in a direction corresponding to an elongated direction of the element being described. The terms “program,” “software application,” and the like as applicable herein, are defined as a sequence of instructions designed for execution on a computer system. A “program,” “computer program,” or “software application” may include a subroutine, a function, a procedure, an object method, an object implementation, an executable application, an applet, a servlet, a source code, an object code, a shared library/dynamic load library and/or other sequence of instructions designed for execution on a computer system. Those skilled in the art can understand the specific meanings of the above-mentioned terms in the embodiments of the present invention according to the specific circumstances. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views and which together with the detailed description below are incorporated in and form part of the specification, serve to further illustrate various embodiments and explain various principles and advantages all in accordance with the present invention. 
         FIG.  1    is a side view of a marine vessel having a through-hull passive electric generator, in accordance with some embodiments; 
         FIG.  2    shows a side cut-away view of a through-hull passive generator, in accordance with some embodiments; 
         FIG.  3    shows a bottom view of a passive generator for marine vessels, in accordance with some embodiments; 
         FIG.  4    shows a top view of a passive generator for marine vessels, in accordance with some embodiments; and 
         FIG.  5    shows a front view of a passive generator, including a barrier over the intake, for marine vessels, in accordance with some embodiments; 
         FIG.  6    shows an initial flow of water through the through-hull passive generator as the marine vessel begins moving through water, in accordance with some embodiments; 
         FIG.  7    shows a steady state operational position of the marine vessel and through-hull passive generator, in accordance with some embodiments; 
         FIG.  8    shows a vessel schematic diagram, in accordance with some embodiments 
         FIG.  9    shows a block diagram of a battery system including a load, a through-hull passive generator, and battery banks where connection of the load and generator is controlled by a charge controller, in accordance with some embodiments; 
         FIG.  10    shows an exemplary test of a system as shown in  FIG.  9   ; and 
         FIG.  11    shows a bar graph of an improvement in overall run time using a system in accordance with that shown in  FIG.  9   . 
     
    
    
     DETAILED DESCRIPTION 
     While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward. It is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. 
       FIG.  1    is a side view of a marine vessel  100  having a through-hull passive electric generator, in accordance with some embodiments. In particular, the vessel is a boat having a hull  102  that sits in the water, and is powered by an outboard motor  106  that is mounted at the transom  116  of the vessel  100 . The outboard motor  106  is generally a self-contained system but requires an external battery  118  to provide electric power for the starter of the outboard motor  106 , or for propulsion operation of an electric motor. The boat may also have electronic systems  114  operated by the battery  118 , such as, for example, radio communication, radar, depth/fish finder, as well as running lights  120 ,  122 . Since all of these devices and the outboard motor  106  depend on the battery  118 , it is imperative that the battery  118  be charged and able to provide power, or that at least an additional power source is present that can provide power in order to avoid being without communications, navigation, or light.  FIG.  8    shows a vessel schematic diagram as an example. Briefly, a battery  802  is used to power an engine starter  804  motor for the outboard engine (e.g.  106 ), as well as various vessel electronics and the vessel lights  806 . As both the engine starter  804  and vessel electrical system  806  consume energy from the battery  802 , a generator  808  is required to charge the battery  802 . 
     The through-hull passive generator system employs a specialized water conduit system that has an intake manifold  110  at the bottom of the hull  102  that forces water through a generator conduit  108  and out through the side of the hull or the transom  116  at the exit  112 , which is generally above the resting water line  104  of the vessel  100 , when the vessel is not moving. The intake manifold  110  is positioned at an opening in the bottom of the hull  102 . As the boat begins to move, propelled by the outboard motor  106 , the design of the intake manifold creates a pressure differential that forces water through the generator conduit  108 . The water flowing through the generator conduit  108  causes an impeller disposed in the generator conduit to turn. 
       FIG.  2    shows a side cut-away view of a through-hull passive generator system, in accordance with some embodiments. The view here is along a central plane in a direction from the front of the vessel to the rear of the vessel.  FIGS.  3 - 5    show other views of the through passive generator system. In these figures, the intake manifold is shown having a tapered opening at the bottom of the vessel. The opening of the intake manifold  110 , for example, has a front edge  204  having a width, and tapers to a rear point  206 . Forward side walls  210  extend from the front edge  204  towards the rear about halfway across the total distance of the opening from front to rear. Rear sidewalls  208  extend from the forward sidewalls  210  at an angle to the rear point  206 . The angle can be about forty degrees relative to the direction of the forward side walls  210 , with a tolerance of +/−five degrees in some embodiments. A top wall  202  of the intake manifold  110  extends from the front edge  204  over the opening and upward to an intake funnel  212  at the top of the intake manifold, and generally behind the centerline, from front to rear, where the forward side walls  210  meet the rear sidewalls  208  at the opening (bottom) of the intake manifold  110 . The distance from the front edge  204  to the centerline is given by arrow  222 . The rear point  206  is behind, from front to rear, of the bottom and rear of the intake funnel  214  by distance  224 . Distance  226  indicates the distance from the centerline to the rear point  206  in the front to rear direction. The top wall  202  is relatively flat at the front edge  204 , but narrows and becomes convex at the back of the tope wall where it meets the intake funnel  212 . 
     The intake funnel has an opening at the top of the intake manifold  110 , starting at about the centerline, and a funnel section  212  that reduces in diameter to a coupling section  214  that is coupled to the first section  216  of the generator conduit  108 . The first section  216  of the generator conduit  108  is a tubular section of conduit angled upward at about a forty degree angle, but can be less or slightly more (e.g. +/−10%). The first portion  216  is joined to an elbow portion  218  that curves to meet the exit portion  220  of the generator conduit  108  that terminates at exit  112  of the generator conduit  108 . The exit  112  of the generator conduit  108  can be covered with a cover  238  that is biased to a closed position by a spring  240 . A screen or mesh  242  can be used to cover the intake opening to prevent objects in the water from entering the intake manifold  110 . As can be seen here, the conduit exit  112  can be completely above the resting water line  104 . 
     An impeller  228  is disposed in the first portion  216  proximate to the coupling section  214  of intake funnel. The impeller is coupled to a shaft  230  that runs along the first portion  216  and exits the top of the elbow section  218  at sealed opening  232 , and is further coupled to a generator motor  234  that is mounted on a base  236 . In general, when the vessel begins to move, water pressure forces water up through the intake manifold  110  and generator conduit  108 , acting on the impeller  228  and causing it, and the shaft  230  to rotate, which in turn rotates the armature of the generator motor  234  to generate electricity. The forward motion of the vessel, as pushed by the outboard motor  106 , combined with the particular geometry of the intake manifold  110  and the tapered opening of intake manifold  110  result in sufficient pressure to force water up and through the generator conduit  108 . That force can also displace the cover  238 , causing the cover  238  to be deflected open to allow water diverted through the generator conduit  108  to pass and exit out of the generator conduit  108 . 
     As can be seen in  FIG.  3   , the intake opening of the intake manifold  110  is shown here as following a five sided shape including a rectangular portion comprised of the front edge  204 , which is the bottom of the top wall  202 , and the bottoms of the two forward side walls  210  at opposite sides of the front edge  204  and at right angles to the front edge. The bottom of the forward side walls extend back from the front edge to a point that is about halfway (distance  222 ) to the rear point  206  from the front edge  204  (in a line normal to the front edge  204 ). Where the bottoms of the forward side walls  210  end the bottoms of the rear side walls  208  extend therefrom to the rear, meeting at the rear point  206  to form a triangular section of the opening that is contiguous with the rectangular portion in the forward region of the intake opening. The width of the front edge  204  can be about twice that of distance  222  and distance  226 .  FIGS.  4  and  5    show a top view and a front view of the intake manifold  110  and the generator conduit  108 . In these views the generator  234  and shaft  232  can be seen on top of the generator conduit  108 . In  FIG.  5    it can be seen that the top wall  202  has a rounded upper portion  502  that follows the opening of the intake funnel  212  and transitions from a rounded profile to a flat, linear edge at front edge  204 . Further, the forward side walls  210  and rear side walls  208  are shown here as flat surfaces. However, it should be understood by those skilled in the art that similar shapes that use more rounded/curved surfaces can be used equivalently. 
       FIGS.  6  and  7    show water flow through the intake manifold as the vessel begins to move ( FIG.  6   ) and as the vessel is at a cruising speed ( FIG.  7   ). Initially, when a boat is not moving, the hull sits in the water such that the water level comes the side of the boat to the water line  104 . Upon engaging the outboard engine  106  the front of the boat will rise as the rear of the boat pushes through the water, creating an angle of the hull  102  relative to the direction of travel  602  as shown in  FIG.  6   . Water pressure will increase against the bottom of the hull  102 , resulting in water flow  606  into the intake manifold, and water pressure at the rear of the opening of the intake manifold  110  created by the narrowing/tapered geometry of the rear portion of the opening of the intake manifold  110  results in a further upward flow  607 , and as a result, water is displaced through the generator conduit  108  until it exits the conduit as indicated by arrow  608 . This water flow can turn the impeller  228  and shaft  230 , and then the generator armature, to create electricity that can be used to charge the battery (e.g.  802 ). Thus, the action of the boat upon moving and the geometry of the intake manifold act to create a flow of water through the generator conduit. Once this flow of water is established, and the boat continues increasing in speed, the boat will be on plane, and the water line relative to the hull will be far below the resting water line  104 . This situation is shown in  FIG.  7   . 
       FIG.  7    illustrates a state where the boat is moving through the water on plane. In that state, the front of the boat and the rear of the boat are more even or level, and bottom of the hull  102  is less angled relative to the surface of the water relative to when it is moving slowly as in  FIG.  6   . However, because water was forced through the generator conduit  108  initially, there is an exit water flow  702  out of the exit  112  of the generator conduit  108 . The momentum of that water flow creates a pressure differential at the opening of the intake manifold  110 , which combined with the pressure differential resulting from the opening of the intake manifold  110  continues to move water through the generator conduit  108 , turning the generator armature in the process. 
       FIG.  9    shows a block diagram of a battery system  900  including a load, a through-hull passive generator, and battery banks where connection of the load and generator is controlled by a charge controller, in accordance with some embodiments. The system  900  includes a first battery bank  904  and a second battery bank  906 , each of which are separately coupled to the charge controller  902 . A load motor  908  is further connected to the charge controller  902  and is configured to provide vessel propulsion. A generator motor  910  is substantially similar to generator motor  234  and is coupled to a through-hull system substantially equivalent to that shown in  FIGS.  1 - 5   . As an example, the charge controller  902  can first connect the load motor  908  to battery bank  904  and the generator motor  910  to the other battery bank  906 . In this configuration, load motor  908  will drain charge from the first battery bank  904  while the second battery bank  906  is charged (or maintained at a charged level if already charged) by the generator  10 . Once the load motor  908  depletes the first battery bank  904 , the charge controller switches the connections such that the load motor  908  is then connected to the second battery bank  906  and the generator  910  is connected to the first battery bank  904  and recharges the first battery bank  904 . The system  900  is a replacement of a single battery bank system without any recharge capability. Then when the second battery reaches a discharge threshold, the charge controller  902  switches back to the initial configuration, and the cycle repeats until both batteries are discharged. Since the generator motor  910  is powered by movement of the vessel, it simply recovers some energy based on water pressure against the hull of the vessel. As a result, the system gains efficiency by achieving some replenishment, but eventually both battery banks become discharged. 
       FIG.  10    shows an exemplary chart  1000  of a test of a system as shown in  FIG.  9   . In the test both the load motor and the generator motor were Nema-17 stepper motors. Each of the battery banks consisted of four HAKADI LiFePO 4  cells connected in series to create a nominal 12.8 Volt. The test was run using a battery manager that switches connections between the battery banks and the load and generator motors as described in reference to  FIG.  9   . In the chart  1000  the vertical axis  1002  represents voltage for each of the two battery banks, which are separately charted on lines  1006  and  1008 . Along the bottom, the horizontal axis represents time. Both battery banks start off charged. For the sake of description, line  1006  will represent the first battery bank and line  1008  will represent the second battery bank. Initially the second load motor is connected to the second battery bank and operated at a load of 1.8 amps, and the generator motor is connected to the first battery bank. To drive the generator motor, water is pumped towards the intake manifold which results in water passing through the conduit (e.g.  108 ) to turn the generator motor. 
     The load motor discharges the second battery bank until it reaches what is considered by the battery manager to be a fully discharged state at time  1010 , at which point the connections are switched; the load motor is connected to the first battery bank and the generator motor is connected to the second battery bank. As a result, the first battery bank begins to discharge and the second battery bank begins to be charged. At time  1012  the first battery bank becomes discharged, and in response, the battery manager again switches the connections back to the initial configuration, and the first battery bank begins charging and the second battery bank is discharged by the load motor. The connections are again switched at time  1014 , and finally at time  1016  both batteries are fully discharged. 
       FIG.  11    shows a bar graph  1100  of a test using a system in accordance with that shown in  FIG.  9    compared to using a single battery bank. The test can be similar to that shown in  FIG.  10    where the battery voltages of both battery banks are charted over time. Bar  1102  shows the use of a single battery bank, without a generator, and bar  1104  shows the system of  FIG.  9    in which two battery banks are used with a generator, and the load and generator connections are changed as one battery bank becomes discharged. Of course, using two battery banks, there will an increase (a doubling of operation time), but using the generator system there is more than a mere doubling of operation time as some energy can be recovered by the inventive through-hull generator system. 
     Thus, the inventive through-hull passive generator system allows the generation of electricity to charge a battery and/or power electrical systems on the boat while the boat is moving. The disclosed system avoids the need for a separate fuel-burning generator, it works at night when solar energy is not available, and it avoids adding super structure to the boat in the form of a wind turbine, which can interfere with activities such as fishing, for example. 
     The claims appended hereto are meant to cover all modifications and changes within the scope and spirit of the present invention.