Abstract:
A fluid hinge includes a first part of a two-part element including a planar surface of a trim tab and a second part of the two-part system having at least one bracket secured to the hull of a watercraft and the first and second parts of the two-part element are not physically coupled together. It also provides at least one bracket secured to the hull on which the planar surface of the trim tab may rest and the at least one bracket not taking any load from the planar surface except at rest to keep the planar surface from descending below the horizon of the hull.

Description:
[0001]    This is a Continuation-in-Part application under 35 U.S.C. 120 of the presently co-pending patent application Ser. No. 14/997,244 filed on Jan. 15, 2016. Additionally, this also is a Continuation-in-Part application under 35 U.S.C. 120 of the presently co-pending patent application Ser. No. 15/474,050 filed on Mar. 30, 2017. This patent application is a continuation-in-part of both the original and the most recent patent applications. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates to an improvement in classical trim-tab technology to enhance the general hydrodynamic performance of a marine craft inclusive of the fuel efficiency thereof. Trim tabs have been known for many years and various forms of them have been developed in an effort to maximize attitude control, stability of the marine craft and general hydrodynamic efficiency inclusive of decrease of flow velocity under the hull and fuel efficiency. 
       BACKGROUND OF INVENTION 
       [0003]    So called boat leveling devices of the trim tab type have been known for many years and various forms of them have been developed in an effort to maximize attitude control, stability of the marine craft and general hydrodynamic efficiency inclusive of decrease of flow velocity under the hull and fuel efficiency. 
         [0004]    The prior art trim tabs are typically provided in pairs to enhance stability of the craft, which are attached directly to the transom of a watercraft and in which the attitude of the trim tab is controlled through a hydraulic piston assembly which controls relative angulation of the whole relative to level of the water. 
         [0005]    In general trim tabs of the prior art, whether double or single acting, will operate upon the same principles and have a common objective, namely, that of contributing to the efficiency control of the boats attitude, stabilization and general hydrodynamics. 
         [0006]    In recent years, most efforts of the prior art have been directed primary to improvement of the electronics in the development of algorithms to optimize trim tab control under various conditions of speed, shape of the boat&#39;s hull, having distribution in craft, and other hydrodynamic considerations. The prior art also has experimented with the efficiency of electric motor controls of the trim tab as opposed to that of the hydraulic systems. 
         [0007]    The trim tabs of the prior art contain a trim tab secured to the hull or transom of a boat with a fixed hinge. When this hinge is fixed, it requires the actuator to be mounted on an angle other than 90 degrees. Placement difficulties arise when the trim tab is mounted under the hull, rather than to the transom of the boat. A need exists for a fluid hinge that allows an actuator to be secured to the transom of the boat, while offering a non-coupled connection of the front of the planar surface of the trim tab to the hull of the boat. 
       SUMMARY OF THE INVENTION 
       [0008]    A fluid hinge includes a first part of a two-part element comprising a planar surface of a trim tab and a second part of the two-part system having at least one bracket secured to the hull of a watercraft and the first and second parts of the two-part element are not physically coupled together. It also provides at least one bracket secured to the hull on which the planar surface of the trim tab may rest and the at least one bracket not taking any load from the planar surface except at rest to keep the planar surface from descending below the horizon of the hull. 
         [0009]    It is accordingly an object of the present invention to provide an improved trim tab system which overcomes the various hydrodynamic limitations of the prior art, also having utility with leisure as well as naval vessels. 
         [0010]    It is another object of the invention to provide a trim tab system capable of inducing a greater change in bow-to-stern or glide angle angulation of the marine craft relative to the water level while increasing the fuel efficiency thereof. 
         [0011]    It is a yet further object to provide a system of the above type which furnishes improved accuracy of adjustment versus prior type of trim tab stern flap systems. 
         [0012]    It is a still further object to provide a system to improve the degree and control of the glide angle of the watercraft and its ability to correct uplift zones to facilitate a more favorable weight distribution, each resulting in reduced fuel costs. 
         [0013]    The present invention therefore seeks to provide more effective trimming coupled with the greatest possible uplift and lowest water resistance values, both at slow and high speeds, in a manner that does not substantially complicate the kinematics of prior art attitude control systems. 
         [0014]    In addition a variety of different fluid hinges are shown herein. 
         [0015]    The above and yet other objects and advantages of the present invention will become apparent from the hereinafter set forth Brief Description of the Drawings, Detailed Description of the Invention and Claims appended herewith. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is an isometric view from the rear of a generic watercraft showing the placement of trim tabs. 
           [0017]      FIG. 2  is the under side of a version of a Fluid Hinge Type- 42 . 
           [0018]      FIGS. 3, 3A, and 3B  are a view of the different parts of a Type- 42  Fluid Hinge including the flange and ears of the bracket. 
           [0019]      FIG. 4  is an isometric view of a trim tab using a Type- 42  Fluid Hinge demonstrating a trim tab in a lowered position. 
           [0020]      FIG. 5  is an isometric view of a trim tab using a Type- 42  Fluid Hinge demonstrating a trim tab in a raised position. 
           [0021]      FIG. 6  is a rear view of a Type- 42  Fluid Hinge showing the Fluid Hinge in a raised position. 
           [0022]      FIG. 7  is a side view of a Type- 52  Fluid Hinge showing the relationship of the Fluid Hinge to a raised and lowered trim tab. 
           [0023]      FIGS. 8 and 8A  are a side view of a Type- 52  focused on the parts of the fluid hinge. 
           [0024]      FIG. 9  is a view of a Type- 52  Fluid Hinge from the rear of the trim tab showing the connection to the hull. 
           [0025]      FIG. 10  is a side view of a Type- 62  and Type- 72  Fluid Hinge. 
           [0026]      FIG. 11  is a side view of a Type- 62  and Type- 72  Fluid Hinge showing the pocket and interaction with a trim tab in a lowered and raised position. 
           [0027]      FIGS. 12 and 12A  are a side view of a Type- 62  and Type- 72  Fluid Hinge focused on the parts of the fluid hinge. 
           [0028]      FIG. 13  is a top rear isometric view of the bracket of the Type- 62  Fluid Hinge. 
           [0029]      FIG. 14  is a top rear isometric view of the bracket of the Type- 72  Fluid Hinge. 
           [0030]      FIG. 15  is a top rear isometric view of the bracket of the Type- 62  Fluid Hinge showing the interaction with a trim tab. 
           [0031]      FIG. 16  is a bottom rear isometric view of the bracket of the Type- 92  Fluid Hinge showing the interaction with a trim tab in a raised position. 
           [0032]      FIG. 17  is a rear cross sectional view showing the securement of the Fluid-Hinge Type- 92 . 
           [0033]      FIG. 18  is a bottom rear isometric view of the bracket of the Type- 82  Fluid Hinge showing the interaction with a trim tab. 
           [0034]      FIG. 19  is a rear cross sectional view showing the securement of the Fluid-Hinge Type- 82 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    The “fluid hinge” refers to a non-coupled connection between the planar surface and the hull of the watercraft. The term “non-coupled” refers to the properties of the fluid hinge that allow the planar surface to rest at low or no speed, but does not restrict the motion needed from the movement of the planar surface between raised and lowered positions of the rear of the trim tab, and further, the fluid hinge is not physically fastened to the planar surface. 
         [0036]      FIG. 1  is an isometric view of a generic watercraft showing the placement of two fluid hinges  49  in combination with trim tabs  41  substantially under the rear portion of the hull  100 ; one on the port side, and one on the starboard side. “Substantially” refers to the positioning as shown in  FIG. 1 , where the tabs may be mostly under the hull, but stick out slightly in order to provide extra space for a connection to an actuator. 
         [0037]      FIG. 2  shows the underside of the trim tab  41  using a version of a fluid hinge Type- 42  and its components thereof. The fluid hinge Type- 42  is comprised of a bracket  57  with an ear  55  that extends away from the hull  100 , further shown in  FIGS. 3, 3A, 3B, 4, 5, and 6 . As shown in  FIGS. 3, 3A, 3B, 4 and 5 , a set of two brackets  57 / 57   a  connects to the hull  100  to support the trim tab  41 . The ears  55  rest against linear-support-tabs  40 , but are not physically coupled together. Instead, the hinge provides support for the planar surface at rest as shown in  FIG. 5  to keep the trim tab from descending below a plane parallel to the horizon of the hull. When the watercraft is moving, the pressure of the water against the planar surface pushes the trim tab against the hull, thus negating the need for a fixed hinge. An actuator  150  connects the rear of the planar surface  26  to the transom  13  of the watercraft. This actuator is used to raise and lower the trim tab  41 . The specific features of the actuator may vary, as any generic actuator would work. It is recommended that the actuator be mounted as close to a 90 degree angle as may be able to void the planar surface  26  from slipping to far away from the fluid hinge. 
         [0038]      FIG. 4  shows an isometric view from the rear of the watercraft of the planar surface  26  of the trim tab  41  dipped at an angle below the plane parallel to the horizon of the hull  100 . It can bee seen that the rear of the planar surface  26  is extended downward from the hull  100  of the watercraft. 
         [0039]    Shown in  FIGS. 7, 8, 8A, and 9  is fluid hinge Type- 52 , involving a bent rod  155  with threaded portion  161  connecting the rod  155  to the hull  100 , and fastened to the hull  100  of the watercraft by use of a threaded top nut  157  and bottom nut  159 . The rod  155  faces the front of the hull  100  and is bent  163  toward the hull  100 . This orientation keeps the planar surface  26  of the trim tab  41  from dipping below the plane parallel to the horizon of the hull  100  of the watercraft a low speeds and rest, similar to the hinge of Type- 42 . The hinge is not physically coupled to the planar surface  26 , or any part of the trim tab  41 . 
         [0040]      FIG. 9  shows a cross sectional rear view of the mounting in more detail. 
         [0041]      FIGS. 10, 11, 12, 12A and 13  show a fluid hinge Type- 62  that involves a pocket  255  enclosing a portion of the planar surface  26 . This portion of the planar surface  26  extends past the linear-support-tabs  40 , as best shown in  FIGS. 12 and 12A  to provide a complemental insertion to the pocket  255  of the fluid hinge  49  Type- 62 . This Type- 62  pocket keeps the planar surface  26  of the trim tab  41  from dipping below the plane parallel to the horizon of the hull  100  of the watercraft a low speeds and rest, similar to the hinge of Type- 42 . The hinge is not physically coupled to the planar surface  26 , or any part of the trim tab  41 .  FIG. 13  shows the pocket bracket of Type- 62  as a continuous piece, while FIG.  14  shows a similar embodiment  72  and  72   a  as smaller pieces that perform the same function, but are mounted separately. Both contain a supporting wall  259 , side wall  255  to keep the planar surface  26  from moving laterally, a bracket  257  where openings  261  can be used in securement to the hull  100 . 
         [0042]    In  FIG. 15  is shown a flexible planar surface  126  using the fluid hinge Type- 62 . The pocket of the hinge formed from the bracket of fluid hinge Type- 62  and the hull  100  of the watercraft provides support for the flexible planar surface  126  at low speeds and rest. This support keeps the flexible planar surface  126  from dipping below the plane parallel to the horizon of the hull  100 . At higher speeds, the planar surface  126  is pushed up against the hull  100  of the watercraft, and there is no need for a hinge. The bracket of fluid hinge Type- 62  allows the planar surface  126  to be physically disconnected from any fixed hinging mechanism, which allows the tab  41  to move freely and accomplish its goal. 
         [0043]      FIG. 16  shows a fluid hinge Type- 92  and  92   a  similar to fluid hinge Type- 42 . The main difference between the two versions is element  55  in the fluid hinge Type- 42  and element  355  in fluid hinge Type- 92 . Element  355  is a rod that protrudes from a bracket  357 . While the look is slightly different, the functionality remains the same. The rod  355  keeps the planar surface  26  of the trim tab  41  from dipping below the plane parallel to the horizon of the hull  100  of the watercraft a low speeds and rest, similar to the hinge of Type- 42 . The hinge is not physically coupled to the planar surface  26 , or any part of the trim tab  41 . 
         [0044]      FIG. 17  further shows the mounting of Fluid Hinge Type- 92 . A series of bolts  361  secure brackets  357  to the hull  100  and are secured by a series of nut  367  inside the hull  100 . Noticed is elements  355  do not physically couple the brackets to the substantially planar surface  26  or its sidewalls  40 , but abutt the side walls of the trim tab. 
         [0045]      FIG. 18  shows fluid hinge Type- 82 . The hinge has two bent rods  455  and  455   a  connected to the hull  100 .  FIG. 14  further shows a trim tab  41  with a flexible planar surface  126  made of a flexible material. The fluid hinge Type- 82  is used to secure the flexible surface  126 , but may also be used to secure the planar surface  26  as shown in previous FIGS. The rods work as a hinge, allowing the surface to be secured to the hull, but not physically coupled. The rods extend through a hole  467  of the planar surface to keep the surface secured, but allows the surface  126  or  26  to move freely when an actuator  150  pushes down on the rear of the tab. The fluid hinge Type- 82  also keeps the front of the surface  126  or  26  of the trim tab  41  from dipping below the plane parallel to the horizon of the hull  100  of the watercraft when the watercraft is at low speeds or rest. 
         [0046]      FIG. 19  further shows the mounting of Fluid Hinge Type- 82 . A threaded rod  461  runs through to the hull  100  and is secured by a nut  457  inside the hull  100 . Noticed is elements  455  do not physically couple the rod  455  to the flexible surface  126 , but fits in a hole  467  (as shown in  FIG. 18 ) provided for the rod  455  to fit through, and further allows the flexible surface  126  to rest at low or no speeds. 
         [0047]    While there has been shown and described above the preferred embodiment of the instant method it is to be appreciated that the method may be embodied otherwise than is herein specifically shown and described and that, within said method, certain changes may be made in the form and arrangement of the parts without departing from the underlying ideas or principles of this method as set forth in the Claims appended herewith.