Patent Publication Number: US-9889909-B2

Title: Apparatus and method for wake shaping

Description:
This is a continuation in part of U.S. patent application Ser. No. 14/444,935 filed Jul. 28, 2014 by applicants which was a US non-provisional patent application related to US Provisional Patent Application No. 61/859,188 filed Jul. 27, 2013 by applicants, which claimed the benefit of the provisional filing date. 
     BACKGROUND 
     Field of Invention 
     The current invention relates to an apparatus and method for modifying the wake of a ski boat. More particularly, a device is temporarily attached to one side of the stern of a boat in order to modify the wake pattern of the boat. 
     Prior Art 
     When the boat hull length is an exact mirror image from side to side, then the boat&#39;s wave rolls from each side of the boat and meets in the center. 
     In the current invention, a wake shaping device is attached on one side of the stern, thereby effectively making one side of the boat longer than the other side. This modification delays the formation of the wave on the opposite side so that it is behind the natural wave formation on the side where the wake shaping device is installed. This modification lifts the water and causes the wake to be taller and longer on the opposite side from the installation of the wake shaping device. The delayed wave on the opposite side of the boat from the wake shaping device allows the wave to crest over the natural wave on the side where the device is installed. 
     The sport of wake surfing is currently the fastest growing segment of behind-the-boat water sports. Wake surfing involves a short surfboard and a short rope that is only used to get up from the water, then is thrown into the boat as the rider gets comfortable on the wave. When the rope is thrown in the boat, the wake surfer rides the boat wake as he or she would an ocean wave. To get a wake large enough to ride, people add ballast bags to the back of the boat, oftentimes on the side where the wake surfer is riding, tilting the boat to one side. It is also common practice to put all of the people in the boat on the side the wake surfer is riding to further weight that side. This tilting of the boat can cause the boat to take on water when going over larger waves and can also cause difficulty for the driver, as weight in the stern of the boat makes the bow of the boat ride higher causing obstructed sight lines. 
     The wake shaping device of the current invention makes ballast and other weighting of the boat less necessary, as the extension of the boat increases wake height and performance without adding weight to the boat. If ballast is used, then the boat can be weighted evenly, and spectators in the boat can distribute their weight more evenly. This affords the driver clearer sight lines for safer driving. It also allows the boat to ride higher in the water, as it was designed, so the boat doesn&#39;t take on water when going over larger waves. For more advanced riders, ballast may be required. 
     Wake surfing is performed close to the stern of the boat, as that is where the boat wake crests and forms the best surfing wake. This can be dangerous for beginner surfers, if they are not accustomed to shifting their weight from front to back on the surfboard to control their momentum and placement on the wake. Surfing so close to the stern of the boat can also be dangerous, as the wake surfer is close to where the exhaust exits the back of the boat. Exhaust fumes can have obvious negative affects on the wake surfer, including carbon monoxide poisoning. 
     The wake shaping device of the current invention elongates the “sweet spot” of the wake, the area where the rope goes slack and the wake surfer can ride without the rope, allowing them to ride further back from the stern of the boat in a safer zone. It also makes the wake taller and firmer, minimizing the froth of the wave. Froth does not have any forward push to give the surfer the momentum needed to stay with the boat. 
     Ballast tanks are filled and drained according to which side the wake surfer surfs on, so there is some down time between surfers if they ride on different sides. The wake shaping device allows for a quicker shift from side to side, as ballast tanks do not need to be emptied and refilled between surfers. 
     In one embodiment of the current invention, there are separate, specifically molded wake shaping devices for port- and starboard-side surfers. 
     In another embodiment, a single wake shaping device may be temporarily installed on either side of the boat by inverting the device when installed on the opposite side. 
     Some makes and models of boats have built in wake surfing devices. Malibu offers Surf Gate™, which is a complicated mechanical system tied to electronics and electric actuators. Electric motors drive a hinged flat board from the back of the platform toward the outside of the boat. It is electronically controlled from the driver&#39;s console. It cannot be retrofitted on other models of boats and costs thousands of dollars as an upgrade package. Nautique&#39;s version is also not retrofittable and costs thousands of dollars for the upgrade package. Nautique has a plate that is mounted flat to the stern of the boat. Electric motors drive the plate out and down, beyond the edge of the boat, changing the wake shape. To get boats with these options, the base boat is nearing $100,000. 
     The wake shaping device of the current invention is much less expensive than the upgrade packages of other manufacturers. 
     In one embodiment, the device may be molded specifically to the design of the different boat manufacturers&#39; sterns, ensuring optimal fit. The devices are retrofittable and can be molded to fit nearly any existing inboard boat&#39;s stern. 
     In another embodiment, the device may be provided with a custom insert that is configured to fit a particular boat model stern profile and platform. 
     In one embodiment, the wake shaping device uses a vacuum cup attachment means. Some manufacturers sterns will require more than one vacuum cup. 
     In one example, the wedge shape of the wake shaping device utilizes water pressure to distribute the load evenly across the fastening side of the device, thereby allowing for a tight fit to the back of the boat. 
     There are not any electronic systems to install or repair. The compact size and light-weight design of the wake shaping device will not clutter or weight down the boat. When the device is not in use, it is stored inside the boat. 
     SUMMARY OF INVENTION 
     In one embodiment of the current invention, a wake shaping device is fastened to one side of the back of an inboard boat. In one example, the wake shaping device comprises a molded scoop-shaped extension, one or more vacuum cups, and safety connection. 
     In another example, the device is attached to a mechanical mounting bracket on the boat stern. 
     In another example, the device is supported by a providing a notch in the mounting face of the device, and resting the device notch on a portion of the boat platform. While the boat is moving forward, water forces the device against the stern, so very little mechanical support is required to hold the device in place. A strap or cord is typically provided to tie the device to the boat if it becomes dislodged, but simply slipping part of the device over a portion of the boat platform has worked well in testing with several boat models. 
     The side and bottom of the wake shaping device work together to displace the water and shape the wake. Reinforcement features may me provided to strengthen the top or bottom surfaces. 
     Varying degrees of a twist or flare can be molded into the wake shaping device to additionally enhance the wake. 
     A vacuum cup may be recessed into the wake shaping device so that the mounting surface attaches to the stern is as close as possible to the boat. Testing has demonstrated that a gap between the stern and the mounting face is not detrimental. 
     A lanyard may be used as a safety in the rare event that suction is lost in the vacuum cup. 
     A vacuum cup pressure relief valve may be extended to above waterline and may be attached to the boat eyelet along with the lanyard. Having the vacuum cup pressure relief valve above waterline allows for easier securing and release from the boat, because air is transferred through the vacuum cup much easier than water. The vacuum cup may have a pump device that is pumped to secure it to the back of the boat. 
     The wake shaping device can be shaped and notched to fit around swim platforms or other features installed by boat manufacturers. 
    
    
     
       DESCRIPTION OF FIGURES 
         FIG. 1  is a side perspective view of an embodiment of a wave shaping device of the current invention attached to the starboard side of the stern of a boat. 
         FIG. 2  is a rear perspective view of the wave shaping device of  FIG. 1 . 
         FIG. 3  is a top perspective view of the wave shaping device of  FIG. 1 . 
         FIG. 4  is a side perspective view of the inside surfaces of the wave shaping device of  FIG. 1 . 
         FIG. 5  is a side view of another embodiment of a wave shaping device of the current invention attached to the port side of the stern of a boat. 
         FIG. 6  is a front perspective view of the wave shaping device of  FIG. 5  resting on a bench. 
         FIG. 7  is a front perspective view of the wave shaping device of  FIG. 5  from a point that would be near the centerline of the boat if the device were mounted. 
         FIG. 8  is a top perspective view of an example vacuum cup assembly and components. 
         FIGS. 9A and 10A  show a wave generated by a ski boat without ballast and without a wave shaping device. 
         FIGS. 9B and 10B  show a wave generated by a ski boat with ballast and without a wave shaping device. 
         FIGS. 9C and 10C  show a wave generated by a ski boat with ballast and with a wave shaping device mounted on the port side of the boat. 
         FIG. 11  is a front perspective wave shaping device with a modified side portion shape. 
         FIG. 12  is a detailed front perspective view of the modified wave shaping device of  FIG. 11 . 
         FIG. 13  is front view of a wake surfer riding a modified wave formed by a wave shaping device mounted on the starboard side of a boat. 
         FIG. 14  is a top rear perspective view of another embodiment of the current invention with only a side surface and a mounting surface. 
         FIG. 15  is a front perspective view of the wave shaping device of  FIG. 14 . 
         FIG. 16  is a side perspective view of the wave shaping device of  FIG. 14  installed on a boat. 
         FIG. 17  is a top perspective view of the wave shaping device of  FIG. 14  installed on a boat. 
         FIG. 18  is a side view of another embodiment of a wave shaping device installed on the port side of a boat. 
         FIG. 19  is an example modified wave produced by the wave shaping device of  FIG. 18 . 
         FIG. 20  is a top perspective view of a wave shaping device mounted to the port side of the stern of a boat by placing a platform index notch over a portion of the boat platform. 
         FIG. 21  is a top view of the wave shaping device of  FIG. 20 . 
         FIG. 22  is a side view looking into the wave shaping device of  FIG. 20 . 
         FIG. 23A  is a simplified front view schematic showing a dual mount wave shaping device mounted on the port side of a boat stern. 
         FIG. 23B  is a simplified top view of an alternate dual mount wave shaping device mounted to the port side of a boat stern. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     Starboard Wave Shaping Device 
       FIG. 1  is a side perspective view of a wave shaping device  101  attached to the starboard side  81  of the stern  90  of a boat  80 .  FIG. 2  is a rear perspective view of the wave shaping device of  FIG. 1 .  FIG. 3  is a top perspective view of the wave shaping device of  FIG. 1 . 
     In this embodiment, the wave shaping device  101  comprises a frame with a side surface  110  which is angled outwardly approximately 12 degrees from the starboard side  81  of the boat  80 . The device also comprises a front mounting surface  150  (not shown) which is preferably shaped to match the mounting area of the stern  90 ; a top surface  120 ; rear surface  130 ; and a bottom surface  140  (not shown). 
       FIG. 4  is a side perspective view of the inside surfaces of the wave shaping device  101  of  FIG. 1 . In this example, the device has a hollow, scoop shape.  FIG. 4  shows the inside surface  142  of the bottom portion of the device; the inside surface  112  of the side portion  110 ; the inside surface  152  of the front mounting portion  150 , and the vacuum cup and pump assembly  300 . In this example, the bottom portion  140  is approximately flush with the bottom edge of the boat in the area of the mounted device. The 12 degree outward angle of the side portion can be observed in  FIG. 4 . Outwardly projecting angles of 5 to 30 degrees have been tested. An outward projecting angle of 12-15 degrees provided the best combination of elongated sweet spot, largest wave, and cleanest wave. 
     Port Wave Shaping Device 
       FIG. 5  is a side view of another embodiment of a wave shaping device  201  of the current invention attached to the port side  85  of the stern  90  of a boat. In this example, the shape of the device is similar to that of example device  101 , with the addition of an offset lip to match the lower profile of the boat at the device mounting area. This example device comprises a side portion  210 , a top portion  220 , and a front mounting surface  250 . 
       FIG. 6  is a front perspective view of the wave shaping device  201  showing the side portion  210 , the top portion  220 , and front mounting surface  250 . The offset lip  260  includes a top extension  262  to accommodate the hull design. The mounting surface  250  has a recess  270  for mounting a single 8 inch diameter vacuum cup. Vacuum cup mounting and access features are provided in the recess area. In other examples, such as when the stern profile does not permit a single large vacuum cup, two or more vacuum cups are provided on the mounting surface. 
       FIG. 7  is a front perspective view of the wave shaping device  201  showing details of the mounting surface  150  which has been shaped to mate with a particular Nautique™ ski boat. The mating surface includes a cutout  258  and recess for the ski platform and recess  259  for the grab handle. The offset lip includes a cutout  264  to accommodate the end of a detail line on the stern of the boat. The vacuum cup mounting recess  270  includes features  272 , a finger hole for releasing the suction of certain models of vacuum cups, mounting screw holes  278 ,  274  where the vacuum pump attaches to the suction cup, and  276  an addition finger hole for releasing the suction of certain models of vacuum cups. Not all manufacturers of vacuum cups have a release valve. 
       FIG. 8  is a top perspective view of a suction cup  310 , a vacuum cup  330 , and a mounting bracket  320  which form an example vacuum cup assembly  301 . In one example, a single vacuum cup assembly is provided with a pair of wave shaping devices—a starboard device and a port device. The model shown is a 6″ SeaSucker™ brand vacuum cup. The vacuum cup assembly is quickly mounted to the desired device for installation. The vacuum pump is applied to the stern of the boat and pumped with the users thumb until the white line does not extend past the edge of the vacuum cup. 
       FIGS. 9A and 10A  show a wave  50  generated by a ski boat  80  without ballast and without a wave shaping device. In this example, the wave is relatively low, frothy, and symmetric. The frothy section of the wave is full of air and has no push to give the surfer momentum needed to stay with the boat. 
       FIGS. 9B and 10B  show a wave  51  generated by a ski boat with ballast and without a wave shaping device. In this example, the wave is higher but is frothy, and symmetric. 
       FIGS. 9C and 10C  show a wave  51  generated by a ski boat with ballast and with a wave shaping device mounted on the port side of the boat as in  FIGS. 1-4 . In this example, the wave is taller and asymmetric, with the surf “sweet spot”  55  portion of the wave substantially firmer and less frothy  56 , and the surf “sweet spot” portion of the wave substantially further from the boat. 
       FIG. 13  is front view of a wake surfer  70  riding a modified wave  53  formed by a wave shaping device mounted on the starboard side  81  of a boat  80 . The clean wave  53  with a curl  54  at the top as seen in this figure is the optimal for propelling the surfboard  72  forward to stay with the boat. When the wake shaper is applied to the port side of the boat, the starboard side is the side where the surfer rides. The wake shaper is applied to the opposite side of where the rider rides. 
     Wave Shaping Device with Side Surface and a Mounting Surface Only 
       FIG. 14-15  are views of another embodiment  201  of the current wave shaping device.  FIG. 15  is a front perspective view of the wave shaping device of  FIG. 14 . In this embodiment, the wave shaping device  201  has only two surfaces—a side surface  212  and a mounting surface  222 . In this prototype, a cross brace  230  was provided to stabilize the inside of the side surface  210  relative to the inside of the mounting surface  220 . Two suction cup assemblies  240  and  250  were provided. Suction cups  241  and  242  were used mount the wave shaping device to the port side of the stern of the boat. 
       FIG. 16-17  are views of the wave shaping device  201  installed on the port side  82  of a boat. In this prototype, duct tape was used to seal between the side surface and the stern. The duct tape was later removed, and the device worked effectively without the seal. Production versions can be tailored to the shape of the stern of particular boat models. 
     Wave Shaping Device with Side Surface Extending Below Hull 
       FIG. 18  is a side view of another example device  301  installed on the port side  82  of a boat. In this example, the bottom surface  340  is positioned about three inches below the hull  85 , and the device produces a steeper wake  58  as shown in  FIG. 19 . 
     Variations 
     Applicant has found that a relatively small frame with a side extension on one side of the boat provides unexpectedly large benefits in wave height, wave firmness, and forming the wave board wave portion further from the boat. Applicant&#39;s invention is not limited to the specific examples described, but includes variations described below and other variations that may be apparent to those skilled in the art. 
     Platform Index Notch Mounting 
       FIG. 20  is a top perspective view of a wave shaping device  401  mounted to the port side  85  of the stern  90  of a boat  80 . This example device comprises a side surface portion  410 , a top portion  420 , a bottom portion  440 , a rear flared portion  430 , and a front mounting surface  450 . The front mounting surface  450  of the on the wave shaping device includes a platform index notch  480  which fits over a portion of platform  92 . The notch includes a reinforcement ridge  482  which strengthens the front mounting surface and which provides additional contact area to the platform  92 . 
       FIG. 21  is a top view of the wave shaping device  401  of  FIG. 20 . Testing has demonstrated unexpected reliability of mounting the device with a platform index notch that fits over a small portion of the platform. In this example, a reinforcement ridge  422  is provided on the top surface  420  in order to strengthen the device. 
       FIG. 22  is a side view looking into the wave shaping device  401  of  FIG. 20 . This view shows detail of the platform index notch  480  fitting over a portion of platform  92 , and the reinforcement ridge  422 . 
     In this example, front mounting surface details for the platform index notch  480  and the reinforcement ridge  422  are configured to match the boat stern and platform. In other examples, the boat-specific stern and platform mating geometries may be provided on an insert plate, so that a wave shaping device  401  front mounting surface  450  may accept various boat model-specific insert plates. 
     Dual Part and Stern Device 
     In the previous examples, separate stern and starboard devices are provided. In other embodiments, a single device may be used on either the stern and starboard side. 
       FIG. 23A  is a simplified front view schematic showing a wave shaping device  402  with a front mounting surface  450  and a side surface  410 . In this example, the device is mounted on the port side of a boat stern so that platform index notch  480   a  fits over a portion of a platform (not shown) port side. The device may be rotated 180 degrees so that a second platform index notch  480   b  fits over a portion of the platform (not shown) starboard side. 
       FIG. 23B  is a simplified top view of a wave shaping device  403  showing a front mounting surface  450   a  mounted to the port side of a boat stern (not shown) so that side surface  410  projects outwardly at angle A. In this example, rear surface  430  serves also serves as the starboard mounting surface  450   b  so that side surface  410  projects outwardly at angle A when the device is mounted on the starboard side. 
     The dual mounting approaches have not been tested, but are expected to work based on the observed insensitivity of the device to top, bottom, and rear surface profiles. 
     Materials 
     The example devices were constructed of vacuum-formed coextrusion of acrylic and ABS. Other materials including polyethylene, polypropylene, other thermoplastics fiberglass, urethane foams, and metal may be used. 
     Vacuum Cup(s) 
     The test boat for the example devices described above had relatively large flat mounting areas on the stern, so a single 8 inch vacuum cup could be used. The 8-inch vacuum cup secured the wave shaping device when the boat was driven at a speed in excess of 25 mph—which is much greater than typical speeds of 7 to 12 mph for wake surfing. 
     The vacuum cup was a model which is used for moving glass and granite slabs. Other vacuum cups that we have used are made by SeaSuckerT™ and include a 4.5″ model and a 6″ model. 
     In other cases, two or more vacuum cups can be provided to provide an adequate mounting area on a more complex stern shape. 
     Some vacuum cups require the user to break the suction by squeezing a tab and relieving the vacuum pressure underneath the cup. 
     Other Mounting Methods 
     In these examples, the wave shaping device was temporarily attached to the boat with vacuum cups. Other mounting methods may be used including various mounting brackets and clamps. 
     Side Angle 
     In various experiments, side outward angles of up to 20 degrees were evaluated. A side angle of about 12 degrees provided the best results for the particular ski boat used. Other boats may have different optimum angles. 
     Side Flare 
     The examples described above have relatively flat side portions. Applicant had expected improved wave shape if the side portions were flared outwardly. However, limited testing has not established that benefit for the test boat used. 
       FIG. 11  is a front perspective wave shaping device  202  with a modified side portion shape  214  relative to the shape of device  101 . In this example, the side portion flares outwardly. 
       FIG. 12  is a detailed front perspective view of the modified wave shaping device  202  showing the flared side portion  214 . The results of this modification did not create the desired effect. When the wake shaper protrudes below the hull level, the wake was altered and, in some cases, improved. 
     Gasket 
     The device was tested with and without a gasket. With the recessed vacuum cup, the gasket did not make a significant improvement on the test boat. Applicant theorizes that the force of the water on the outwardly projecting side surface acts to compress the vacuum cup against the stern and to resist shear forces that would detach the device. 
     Mounting Shape 
     The example devices were designed for a particular boat model, including cutouts for a swimming platform and a lip extension. Other boat models might have different mounting surface profiles. 
     The scope of the invention is not limited to the particular examples and embodiments described above.