Abstract:
A lightweight tender comprising a hull constructed from substantially a single piece of composite material and a retractable pillar attached to the hull, wherein the retractable pillar defines a longitudinally extending channel. A retractable carbon fiber bimini cover is pivotingly attached to the retractable pillar, and defines a top deck when the pillar is retracted, and defines a bimini top extended. A first end of a brace is hingedly attached to the bimini cover and a second end of the brace travels within the longitudinally extending channel of the retractable pillar such that the angle between the bimini cover and the retractable pillar increases as the brace travels distally within the longitudinally extending channel.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application seeks priority to U.S. Provisional Patent Application Ser. No. 61/551,795 filed on Oct. 26, 2011 entitled “Composite Tender with Retractable Bimini Hard-Top and Associated Methods,” the contents of which are incorporated by reference herein. 
    
    
     FIELD OF INVENTION 
     The present invention generally relates to the field of boating. More particularly, the present invention is in the field of composite tender and dinghy design and manufacturing. 
     BACKGROUND 
     Tenders or dinghies are a class of boat typically used to service larger sea vessels. Large sea vessels, such as yachts, often can not dock due to physical restrictions or time constraints. It is therefore advantageous for a yacht to carry an on-board tender for trips from the yacht to the shore. 
     Tenders are relatively small craft, so the number of passengers that can safely occupy a typical tender is limited. Tenders are ideally small and lightweight so to not be unduly burdensome to the vessel on which the tender resides. Due to size and weight limitations, a yacht&#39;s tender is typically either an inflatable boat or a rigid-hulled inflatable boat (RIB). 
     Inflatable boats are made of soft materials, such as rubber, and are susceptible to punctures which render the boat not seaworthy. Additionally, ultraviolet rays from the sun can cause degradation that compromises the boats integrity. RIBs also have inflatable tubes at the gunwale that are equally susceptible to punctures and degradation. The shape of inflatable boats and RIBs also typically renders them relatively slow vessels as compared to rigid hulled speedboats of the same size and power class. 
     Additionally, inflatable boats often lack protection from the sun or rain due to their small size and the limited ability to install a bimini top as a result of soft-material construction. This limitation in size combined with the fact that these craft typically have outboard motors also precludes the installation of a large stern diving deck projecting from the transom. 
     Lastly, the configuration of inflatable boats and RIBs limits the number of passengers that can safely and comfortably occupy the vessel. Much improved vessels are needed in the field. 
     SUMMARY 
     Accordingly, an object of the present invention is to provide a lightweight tender that is not susceptible to punctures yet can comfortably seat a number of passengers while not being too large for accommodation by a yacht. 
     A further object of the present invention is to provide a lightweight tender having a bimini hard top that is retractable to accommodate the constraints of yacht storage while still allowing a means of protection from the elements. 
     A further object of the present invention is to provide a lightweight tender having comfortable and practical seating accommodations. 
     A further object of the present invention is to provide a lightweight tender having a folding dive platform to allow recreational activities while accommodating the need to maintain a small storage footprint. 
     Accordingly, the present invention is directed to a rigid hull yacht tender of carbon fiber construction comprising a retractable bimini hard-top. The tender is of a sleek design to promote performance, can protect the operator from the elements due to a retractable bimini hard-top, is lightweight, has a small profile due to the retractable bimini hard top so that the tender is easily stored on a yacht, has a foldable aft dive deck, and has comfortable and plentiful seating. 
     In particular, the invention contemplates a lightweight tender with a hull constructed from substantially a single piece of composite material, such as carbon fiber. The hull also has a gunwale and a retractable pillar attached proximate an interior surface of the hull. The retractable pillar has a channel that extends longitudinally along the pillar. 
     A bimini cover made from a rigid material is pivotingly attached to the retractable pillar. The bimini cover defines a top deck when the retractable pillar is in the retracted orientation, and it defines a bimini top when the retractable pillar is in the extended orientation. 
     A brace having a first end and a second end is hingedly attached to the bimini cover by its first end, and the second end travels within the longitudinally extending channel of the retractable pillar such that the angle between the bimini cover and the retractable pillar increases as the brace travels distally within the longitudinally extending channel. 
     In another embodiment, the bimini cover seals against the gunwale when in a closed position, defining a compartment that is substantially sealed. 
     In yet another embodiment, the retractable pillar comprises a linear actuator that is connected to the second end of the brace for the purpose of moving the brace along the longitudinally extending channel. In a related embodiment, the linear actuator is internal to the retractable pillar. In a preferred embodiment, the bimini cover is made from composite material, such as carbon fiber. 
     The lightweight tender may further comprise a folding dive platform attached to a transom formed with the hull, wherein the folding dive platform folds upwards into a closed position that is substantially parallel to the transom and also folds outwards into an open position that is substantially perpendicular to the transom. 
     The lightweight tender also, in a related embodiment, comprises a sponson attached to the hull that substantially circumscribes the tender. The sponson comprises closed cell foam surrounded by a polyurethane sheath. 
     The tender also comprises an inboard motor. 
     In an embodiment of the retractable bimini cover, a carbon fiber top panel is of a size and dimension to substantially cover a tender cockpit when in an extended position and to substantially cover a storage space when in a retracted position. A first retractable pillar is hingedly attached to the carbon fiber top panel and to the tender, while a second retractable pillar is also hingedly attached to the carbon fiber top panel and to the tender. A first brace is attached between the first retractable pillar and to the carbon fiber top panel, and a second brace is attached between the second retractable pillar and to the carbon fiber top panel. 
     A linear actuator with the first retractable pillar is attached to the first brace, wherein the linear actuator changes the position of the first brace on the first pillar to change the angle of the carbon fiber top with respect to the first pillar. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the invention, reference is made to the following detailed description, taken in connection with the accompanying drawings illustrating various embodiments of the present invention, in which: 
         FIG. 1  is a perspective view of one embodiment of the hull of the tender; 
         FIG. 2  is a perspective view of one embodiment of the tender hull of  FIG. 1  having a bimini hard top; 
         FIG. 3  is a side view of one embodiment of the tender of  FIG. 2  with the bimini hard top in a retracted state; 
         FIG. 4  is a top view of one embodiment of the tender of  FIG. 2  with the bimini hard top in a retracted state; 
         FIG. 5  is a perspective view of one embodiment of the tender of  FIG. 2  with the bimini hard top in a retracted state; 
         FIG. 6  is a side view of one embodiment of the tender of  FIG. 2 ; and 
         FIG. 7  is a rear view of one embodiment of the retractable rear deck of the tender. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention will now be described more fully with reference to the accompanying drawings and photos in which alternate embodiments of the invention are shown and described. It is to be understood that the invention may be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein. Rather, these embodiments are provided so that this disclosure may be thorough and complete, and will convey the scope of the invention to those skilled in the art. 
     With reference initially to  FIG. 1 , one embodiment of the present invention includes a tender  100  of composite monohull  102  construction. The preferred composite is carbon-fiber-reinforced polymer (also known as carbon-fiber-reinforced plastic, but hereinafter simply “carbon fiber”). However, other composite materials may also be employed instead, or in addition to carbon fiber, including glass fiber and Kevlar®. 
     The carbon fiber fabric is at least one of a unidirectional fabric, bidirectional fabric, or a woven fabric. At least one layer of carbon fabric is used in the construction of the monohull  102 . In embodiments wherein multiple layers of fabric are utilized, the orientation of the fabric layers with respect to each other (e.g. ±45°), is adjusted to maximize integrity of the final structure. This allows the use of non-woven fabric layers, the individual fibers of which remain in a straight orientation (which would otherwise be naturally crimped in a woven fabric), and therefore possess an intrinsically high tensile strength and stiffness allowing greater tensile and compression forces to be absorbed by the final structure. In one embodiment of the construction process, layers of fabric are stitched together before being placed in a hull mold. 
     A polymer is infused into the composite fiber, being at least one of epoxy, polyester, vinyl-ester, and nylon. Epoxy is the preferred polymer. The polymer is infused into the carbon fiber using at least one of a wet lay-up technique, hand lay-up, hand-lay up with vacuum compression, infusion vacuum compression, and compression molding, all of which are well known in the art. Upon infusion, the composite parts are at least one of air- and heat-cured. 
     The molds for the monohull  102 , deck  104 , and any other composite pieces are made from at least one of fiberglass, carbon fiber, aluminum, and any other mold material known in the art. The molds are polished, waxed, and a release agent is applied to the mold before the fabric and resin are applied utilizing methodologies well known in the art. 
       FIG. 2  illustrates the tender  100  comprising a hard bimini top mechanism  200  that is retractable. The retraction mechanism is either manual or motorized. In the upright position, a top panel  202  forms a cover from the elements. In the retracted position ( FIG. 3 ), the top panel  202  forms a cover that extends forward towards the bow bulwark  204  of the tender, and also extends aft of the bow, in the directions extending towards the port bow bulwark  206  and starboard bow bulwark  208  ( FIG. 4 ). In one embodiment, the top panel  202  sealedly engages the bulwarks  204 ,  206 ,  208 , thereby creating a forward top deck and as shown in  FIG. 5  a corresponding compartment  210  under the deck that is, from the top side of the tender, sealed from the elements. In one embodiment, additional aft panels are installed engaging the aft edge  212  of the top panel  202 , extending downward to engage the sole of the cockpit area  214 , fully sealing the forward compartment when the top panel is retracted. In one embodiment, the aft panels are molded into the body of the tender and the aft edge  212  of the top panel  202  sealedly engages these aft molded panels and also sealedly engages a console housing  216 . In one embodiment, the edges of the top panel do not sealedly engage the bulwarks. 
     In the retracted position ( FIGS. 4 and 5 ), the top panel  202  adds structural integrity to the tender. In one embodiment, the top panel  202  is reinforced with rails that traverse the top panel  202  in the port/starboard orientation. The top panel  202  engages the bulwarks  204 ,  206 ,  208  and is securely situated using the force applied by the motorization mechanism. In another embodiment, the top panel  202  engages the bulwarks  204 ,  206 ,  208  and is securely situated using mechanical fasteners commonly utilized in the art. 
     The bimini hard-top mechanism  200  comprises at least one, and preferably two main pillars  216   p  and  216   s . The pillars  216   p ,  216   s  are constructed from at least one of aluminum, stainless steel, titanium and composite materials. The pillars  216   p ,  216   s  comprise at least one hinged joint that allows the pillars to fold upon themselves to allow the bimini hard top mechanism  200  to retract. In one embodiment, pillar hinge joints actuate using at least one motor assembly. The motor assembly comprises at least one of a direct current motor, stepper motor, gear head transmission, chain drive, rigid chain actuator, belt drive, rigid belt actuator, screw drive, winch, rack and pinion, and any other motorized assemblies known in the art. 
     At the most distal end of each pillar  216   p ,  216   s  a hinge  218   p ,  218   s  communicates with a top panel  202 . When retracted, the angle between the top panel  202  and the pillars  216   p ,  216   s  approaches 0°, but in the upright position, the angle approaches 90°. The angle of the top panel  202 , when in the upright position, is adjustable. In one embodiment, the angle of the top panel  202  adjusts automatically based on input from sensors that detect at least one of wind speed, wind direction, tender speed, and tender direction. 
     The adjustment of the angle of the top panel  202  is actuated by at least one brace. In a preferred embodiment there are two braces, a port side brace  220   p  and a starboard side brace  220   s , that correspond to a port side pillar  216   p  and starboard side pillar  216   s  respectively. The port side brace  220   p  extends aft from the port side pillar  216   p  to hingedly engage the top panel  202  proximate the port side edge  222   p  of the top panel  202 , and the starboard side brace  220   s  extends aft from the starboard side pillar  216   s  to hingedly engage the top panel  202  proximate the starboard side edge  222   s  of the top panel  202 . The braces  220   p ,  220   s  each hingedly engage their respective pillars  216   p ,  216   s.    
     In one embodiment, the pillar-side hinge assembly  224   p ,  224   s  of a brace  220   p ,  220   s  resides in a channel in the pillar. A hinge assembly  224   p ,  224   s  can move within a channel  225   s .  225   p  (only  225   s  shown in detail view for efficiency of illustration) which causes the angle of the top panel  202  to change. In particular, as a hinge assembly  224   p ,  224   s  travels distally within a pillar channel, the angle between a pillar  216   s ,  216   p  and a brace  220   s ,  220   p  increases, causing the brace-to-top panel hinge  226   s ,  226   p  ( 226   p  as a port-side brace-to-top panel hinge is not visible in the figures, as it is occluded by the top panel  202 ) angle to decrease, which results in the angle of the top panel/pillar apex to increase. 
     A pillar-side hinge assembly  224   p ,  224   s  slides within a pillar channel manually when a force is applied to either the top panel  202  or a brace  220   s ,  220   p . When the desired angle of the top panel  202  is reached, a pillar-side hinge assembly  224   p ,  224   s  is mechanically secured in place using fastening mechanisms well known in the art. In one embodiment, a pillar-side hinge assembly  224   p ,  224   s  slides within a pillar channel due to a linear actuator. The linear actuator is one of a chain drive, rigid chain actuator, belt drive, rigid belt actuator, screw drive, winch, rack and pinion, and any other linear actuator known in the art. 
     In one embodiment of the tender, the composite monohull  102  has a channel that substantially circumscribes the tender, proximate the bulwarks, which accommodates at least one sponson  106 . The sponson  106  adds additional buoyancy, stability against capsize, and protects the composite monohull  102  from collision damage. 
     In one embodiment, the sponson  106  is a polyurethane sheath surrounding closed-cell foam. The foam provides shock absorption, and is impervious to being deflated. The foam can be molded to make a profile that complements the aesthetics of the tender. In another embodiment, the foam core is not solid, but rather a series of high-density foam tubes packed into a series of chambers. The chambers are inflatable, but the foam preserves a majority of buoyant properties of the intact chambers in the event of deflation or a puncture. 
     In one embodiment, the sponson  106  is an air/foam hybrid comprising an internal inflatable air bladder surrounded by a foam-filled outer sheath. The outer sheath remains aesthetically wrinkle-free due to the tension provided by the underlying air bladder, provides superior shock absorption, and the foam prevents total sponson deflation. The foam can be molded to make a profile that complements the aesthetics of the tender. 
     The sponsons  106  may be air-holding tubes that are substantially cylindrical in shape comprising monohull  102  attachment points. The sponsons  106  may instead be D-shaped so that the monohull  102  maintains a lower profile. The sponsons  106  may also be extrusions of a substantially compliant material, such as rubber, PVC, plastic, or any sponson material known in the art. 
     In another embodiment, absent a sponson channel, at least one sponson  106  is attached to the monohull  102 . In this embodiment the sponsons  106  are mechanically fastened to the monohull  102  using fasteners well known in the art. 
     The tender  100  is powered by at least one of a fuel engine, electric motor, and fuel hybrid-electric motor. A fuel engine is configured to be one of an outboard configuration and inboard configuration. The fuel engine is one of a propeller drive well known in the art and an impeller-driven pump jet drive well known in the art. An electric motor is configured to be one of an outboard configuration and inboard configuration. The electric motor is one of a propeller drive well known in the art and an impeller-driven pump jet drive well known in the art. A fuel hybrid-electric motor is configured to be one of an outboard configuration and inboard configuration. The fuel hybrid-electric motor is one of a propeller drive well known in the art and an impeller-driven pump jet drive well known in the art. 
       FIG. 1  illustrate one embodiment of the tender  100  wherein a stern deck  108  extends aft from the transom  110  capable of bearing the weight of multiple persons. The preferred embodiment is a tender  100  with inboard propulsion so that the stern deck  108  extends substantially across the transom  110 . In one embodiment, the stern deck  108  hingedly attaches to the aft side of the transom using mechanical fasteners and hinge assemblies well known in the art. The hinge assemblies  112  allow the stern deck to hingedly swing roughly 90° of travel so that when extended it is substantially parallel with the waterline and when in the upright position it is substantially parallel with the transom  110 .  FIG. 7  illustrates the tender  100  with the stern deck  108  positioned upwards to fold inwards towards the transom bulwark  114  so that the length of the tender  100  is minimized which is conducive to efficiently storing the tender  100  on a yacht. Similarly, when the tender  100  is being piloted through water, the stern deck  108  is preferably positioned upwards to fold towards the transom bulwark  114 . 
       FIGS. 8-9  are alternate views of the invention. 
     Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings and photos. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and alternate embodiments are intended to be included within the scope of the claims supported by this specification.