# Patent

## Title
Wake-modifying device for a boat

## Abstract

A recreational sport boat includes a hull, having starboard and port sides and a transom, and a pair of wake-modifying devices positioned aft of the transom. One of the wake-modifying devices is positioned on a port side of the boat's centerline and another of the wake-modifying devices is positioned on a starboard side of the boat's centerline. Each wake-modifying device includes a plate-like member and at least one downturned surface at a trailing portion of the plate-like member. Each wake-modifying device is pivotable between a non-deployed position and a deployed position about a pivot axis that is horizontal or inclined no more than about 35° from horizontal. When a wake-modifying device is in the deployed position, the downturned surface is lower than it is in the non-deployed position so as to be able to modify the boat's wake.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/889,752, filed Oct. 11, 2013, and titled “Wake-Modifying Device for a Boat.” The foregoing application is hereby incorporated by reference in its entirety and is made a part of this specification for all that it discloses.


FIELD OF THE INVENTION
The invention relates to a device for modifying the wake of a boat, as well as a boat equipped with one or more such devices.
BACKGROUND OF THE INVENTION
Recreational sport boats are often used to tow water sports performers such as water skiers, wakeboarders, wake surfers, and the like. The optimal wake depends on which of these water sports a boat is used for, as well as the preferences and skill level of the performer. Water skiers generally prefer a relatively smooth water surface, while wakeboarders and wake surfers desire bigger wakes and wakes with more defined shapes. In recent years, boats have been equipped with various means for modifying the wake of the boat depending on how the boat is being used.
One example of a conventional means used to modify a boat's wake is a trim tab. Trim tabs originally were designed to adjust the trim of a boat. For example, when a boat is overloaded on the port side causing the boat to list to port, a trim tab may be deployed on the port side to cause the boat to return to an even keel. More recently, trim tabs have been used to purposefully modify the wake of a boat. One way to do so is to use one or more trim tabs to lift the stern of the boat. Lifting the stern minimizes the wake of a boat, resulting in a relatively smooth water surface, which is desirable for water skiing. Another way that trim tabs have been used is to increase the displacement of one side of the boat, which increases the size of the wake on the side of the boat with the increased displacement.
FIG. 1 shows the transom 122 of a boat used to tow a water sports performer. Three trim tabs 10, 20, 30 known in the art are mounted on the transom 122: one on the port side, one at the centerline, and one on the starboard side. Each tab is pivotably attached to the transom 122 of the boat by a hinge 11, 21, 31. The port and starboard trim tabs 10, 30 are flat plates, with inboard and outboard edges bent upwards at a 90° angle. The upwardly-extending portion of each tab extends approximately 1⁄4 inch above the upper surface of the flat portion of the tabs. The center trim tab 20 also is a flat plate, with inboard and outboard edges bent downwards at a 90° angle and a trailing edge bent upwards at a 90° angle. The downwardly-extending portions of the center tab extend approximately 1⁄8 inch below the lower surface of the flat portion of the tab, and the upwardly-extending portion extends approximately 1⁄4 inch above the upper surface of the flat portion. The edges of the trim tabs 10, 20, 30 are bent upwards or downwards to aid in the manufacturing process and the extent to which the edges extend upwards or downwards is preferably minimized.
Each of the aforementioned trim tabs 10, 20, 30 is pivotable between a non-deployed position and a deployed position. In FIG. 1, the port trim tab 10 is shown in a deployed position and the starboard trim tab 30 is shown in a non-deployed position. A linear actuator 510 moves each tab between the non-deployed position and the deployed position. As the boat moves through the water, the water flowing under the boat impinges on the deployed trim tab, creating an upward force on the tab. As a result, the portion of the boat where the trim tab is attached is raised. When used for water skiing, the center tab 20 may be deployed to raise the entire stern of the boat and minimize the wake. To increase the wake of the boat for wake surfing, either one of the port or starboard trim tabs may be deployed. When the port trim tab 10 is deployed, for example, the port side of the boat is raised, causing an increase in displacement on the starboard side of the boat, which increases the size of the starboard wake. The side of the boat with the increased wake is the surf side, which, in this example, is the starboard side. To further increase the size of the wake, ballast may also be added to the surf side of the boat.
In the embodiment shown in FIGS. 1 and 2, the port and starboard trim tabs 10, 30 are not perfectly rectangular, but rather have an angled contour along their outboard edges. This is so that the trim tabs do not extend beyond the outer perimeter of a swim platform (not shown) mounted to the transom 122 of the boat, above the trim tabs 10, 20, 30. Alternatively, all of the trim tabs may have a rectangular shape.
Even with the trim tabs described above, wakeboarders and wake surfers desire larger wakes with improved shapes. For surfing in particular, wake surfers desire a wake with a large surfable area. The surfable area is the portion of the wake that pushes the surfer forward. This area generally extends from the curl of the wake to the swim platform.
SUMMARY OF THE INVENTION
In one aspect, the invention relates to a wake-modifying device adapted to be attached to a boat, aft of the boat's transom, on either a port or starboard side of the boat's centerline.
In another aspect, the invention relates to a recreational sport boat including a hull, having starboard and port sides and a transom, and a pair of wake-modifying devices positioned aft of the transom. One of the wake-modifying devices is positioned on a port side of the boat's centerline and another of the wake-modifying devices is positioned on a starboard side of the boat's centerline. Preferably, each wake-modifying device is pivotably attached directly to the transom. Alternatively, one or both of the wake-modifying devices may be attached to other portions of the boat, such as the bottom or sides of the hull or a swim platform.
Each wake-modifying device includes a plate-like member and at least one downturned surface at a trailing portion of the plate-like member. Each wake-modifying device is pivotable between a non-deployed position and a deployed position about a pivot axis that is horizontal or inclined no more than about 35° from horizontal. In the deployed position, the downturned surface is lower than it is in the non-deployed position so as to be able to modify the boat's wake.
The plate-like member and the downturned surface of each wake-modifying device may be an integral piece or separate pieces joined together. The downturned surface may be at a trailing edge of the plate-like member, for example, when they are an integral piece. Or the downturned surface may be inward of the trailing edge, for example, when the downturned surface is a separate piece attached to a lower surface of the plate-like member.
Preferably, an angle between the downturned surface of each wake-modifying device and a lower surface of a central portion of the plate-like member is between about 120° to about 135°, and the downturned surface extends between about 1 inch to about 21⁄4 inches below the lower surface of the plate-like member. The downturned surface may be oriented such that it intersects the plate-like member along a line that is generally parallel to the pivot axis, or along a line that is at an oblique angle relative to the pivot axis. The downturned surface and the plate-like member need not intersect along a straight line, and may instead intersect along a curved line.
Preferably, each wake-modifying device includes not one but two (or more) downturned surfaces at a trailing portion of the plate-like member. A first one of the downturned surfaces may intersect the plate-like member along a line that is generally parallel to the pivot axis, and a second one of the downturned surfaces may intersect the plate-like member along a line that is at an obtuse angle relative to the line along which the first downturned surface and the plate-like member intersect. Preferably, the obtuse angle is between about 135° to about 150°, and the first downturned surface is outboard of the second downturned surface.
Each wake-modifying device may also include at least one upturned surface at an outboard portion of the plate-like member, between the downturned surface and the pivot axis. The plate-like member and the upturned surface may be an integral piece or separate pieces joined together, and the upturned surface may be at an outboard edge of the plate-like member or inward of the outboard edge. An angle between the upturned surface and an upper surface of a central portion of the plate-like member preferably is between about 30° to about 150°, and more preferably is about 90°. The upturned surface preferably extends at least about 1 inch above an upper surface of the plate-like member.
At least one of the wake-modifying devices may include another downturned surface at an inboard portion of the plate-like member, between the first downturned surface and the pivot axis. An angle between this downturned surface and the lower surface of a central portion of the plate-like member preferably is between about 30° to about 150°, and more preferably is about 90°. The plate-like member and this downturned surface may be an integral piece or separate pieces joined together, and the downturned surface may be at an inboard edge of the plate-like member or inward of the inboard edge.
At least one of the wake-modifying devices may also include at least one fin attached to the lower surface of the plate-like member. An angle between the fin and the lower surface of the plate-like member preferably is between about 30° to about 150°, and more preferably is about 90°. The fin preferably extends at least about 1 inch below the lower surface of the plate-like member. The fin and the plate-like member preferably intersect along a line that is at an angle between about 15° and about 75° relative to the pivot axis, and more preferably between about 30° and about 60° relative to the pivot axis, and extends in a direction aft and outboard from the pivot axis. In some cases, it may be desirable to have at least two fins, which preferably are parallel to each other.
Each wake-modifying device preferably is capable of assuming multiple deployed positions. In each different deployed position the wake-modifying device is pivoted downwardly at a different angle relative to the non-deployed position. The boat may include a pair of linear actuators, each operable to move a respective one of the wake-modifying devices between its non-deployed position and its deployed position. The boat also preferably includes an operator station with a controller configured to control the operation of each linear actuator.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a transom of a boat equipped with prior art trim tabs.
FIG. 2 is a detailed view the starboard trim tab shown in FIG. 1.
FIG. 3 shows a boat including a pair of wake-modifying devices according to a first preferred embodiment of the invention.
FIG. 4 is a stern view of the boat shown in FIG. 3.
FIG. 5 is a detailed view of the port wake-modifying device shown in FIG. 3.
FIG. 6 is a detailed view of the bottom of the port wake-modifying device shown in FIG. 3.
FIG. 7 is a perspective view of the port wake-modifying device shown in FIG. 3, detached from the boat and shown here from the inboard side.
FIG. 8 is a perspective view of the port wake-modifying device shown in FIG. 7, shown here from the outboard side.
FIG. 9 is a perspective view of the port wake-modifying device shown in FIG. 7, turned upside down and shown here from the outboard side.
FIG. 10 is an outboard elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 11 is an inboard elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 12 is an aft elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 13 is a top elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 14 is a foreside elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 15 is a bottom elevation view of the port wake-modifying device shown in FIG. 7.
FIG. 16 is a port side view of the boat shown in FIG. 3, with the port wake-modifying device in a non-deployed position.
FIG. 17 is a port side view of the boat shown in FIG. 3, with the port wake-modifying device in a deployed position.
FIG. 18 is a manufacturing view of the port wake-modifying device shown in FIG. 7.
FIG. 19 is a perspective view of the starboard wake-modifying device shown in FIG. 3, detached from the boat and shown here from the outboard side.
FIG. 20 is a perspective view of the starboard wake-modifying device shown in FIG. 19, shown here from the inboard side.
FIG. 21 is a perspective view of the starboard wake-modifying device shown in FIG. 19, turned upside down and shown here from the outboard side.
FIG. 22 is an inboard elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 23 is an outboard elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 24 is an aft elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 25 is a top elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 26 is a foreside elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 27 is a bottom elevation view of the starboard wake-modifying device shown in FIG. 19.
FIG. 28 is a starboard side view of the boat shown in FIG. 3, with the starboard wake-modifying device in a non-deployed position.
FIG. 29 is a starboard side view of the boat shown in FIG. 3, with the starboard wake-modifying device in a deployed position.
FIG. 30 is a manufacturing view of the starboard wake-modifying device shown in FIG. 19.
FIG. 31 is a stern view of a boat including a pair of wake-modifying devices according to a second preferred embodiment of the invention.
FIG. 32 is a detailed view of the port wake-modifying device shown in FIG. 31.
FIG. 33 is a detailed view of the bottom of the port wake-modifying device shown in FIG. 31.
FIG. 34 is a perspective view of the port wake-modifying device shown in FIG. 31, detached from the boat and shown here from the inboard side.
FIG. 35 is a perspective view of the port wake-modifying device shown in FIG. 34, shown here from the outboard side.
FIG. 36 is a perspective view of the port wake-modifying device shown in FIG. 34, turned upside down and shown here from the outboard side.
FIG. 37 is an outboard elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 38 is an inboard elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 39 is an aft elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 40 is a top elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 41 is a foreside elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 42 is a bottom elevation view of the port wake-modifying device shown in FIG. 34.
FIG. 43 is a port side view of the boat shown in FIG. 31, with the port wake-modifying device in a non-deployed position.
FIG. 44 is a port side view of the boat shown in FIG. 31, with the port wake-modifying device in a deployed position.
FIG. 45 is a manufacturing view of the port wake-modifying device shown in FIG. 34.
FIG. 46 is a perspective view of the starboard wake-modifying device shown in FIG. 31, detached from the boat and shown here from the outboard side.
FIG. 47 is a perspective view of the starboard wake-modifying device shown in FIG. 46, shown here from the inboard side.
FIG. 48 is a perspective view of the starboard wake-modifying device shown in FIG. 46, turned upside down and shown here from the outboard side.
FIG. 49 is an inboard elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 50 is an outboard elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 51 is an aft elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 52 is a top elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 53 is a foreside elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 54 is a bottom elevation view of the starboard wake-modifying device shown in FIG. 46.
FIG. 55 is a starboard side view of the boat shown in FIG. 31, with the starboard wake-modifying device in a non-deployed position.
FIG. 56 is a starboard side view of the boat shown in FIG. 31, with the starboard wake-modifying device in a deployed position.
FIG. 57 is a manufacturing view of the starboard wake-modifying device shown in FIG. 46.
FIG. 58 is a stern view of a boat including a pair of wake-modifying devices according to a third preferred embodiment of the invention.
FIG. 59 is a detailed view of the port wake-modifying device shown in FIG. 58.
FIG. 60 is a detailed view of the bottom of the port wake-modifying device shown in FIG. 58.
FIG. 61 is a perspective view of the port wake-modifying device shown in FIG. 58, detached from the boat and shown here from the inboard side.
FIG. 62 is a perspective view of the port wake-modifying device shown in FIG. 61, shown here from the outboard side.
FIG. 63 is a perspective view of the port wake-modifying device shown in FIG. 61, turned upside down and shown here from the outboard side.
FIG. 64 is an outboard elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 65 is an inboard elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 66 is an aft elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 67 is a top elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 68 is a foreside elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 69 is a bottom elevation view of the port wake-modifying device shown in FIG. 61.
FIG. 70 is a port side view of the boat shown in FIG. 58, with the port wake-modifying device in a non-deployed position.
FIG. 71 is a port side view of the boat shown in FIG. 58, with the port wake-modifying device in a deployed position.
FIG. 72 is a manufacturing view of the port wake-modifying device shown in FIG. 61.
FIG. 73 is a perspective view of the starboard wake-modifying device shown in FIG. 58, detached from the boat and shown here from the outboard side.
FIG. 74 is a perspective view of the starboard wake-modifying device shown in FIG. 73, shown here from the inboard side.
FIG. 75 is a perspective view of the starboard wake-modifying device shown in FIG. 73, turned upside down and shown here from the outboard side.
FIG. 76 is an inboard elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 77 is an outboard elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 78 is an aft elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 79 is a top elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 80 is a foreside elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 81 is a bottom elevation view of the starboard wake-modifying device shown in FIG. 73.
FIG. 82 is a starboard side view of the boat shown in FIG. 58, with the starboard wake-modifying device in a non-deployed position.
FIG. 83 is a starboard side view of the boat shown in FIG. 58, with the starboard wake-modifying device in a deployed position.
FIG. 84 is a manufacturing view of the starboard wake-modifying device shown in FIG. 73.
FIG. 85 shows an exemplary control screen for operating the wake-modifying devices shown in the previous figures.
FIG. 86 shows an edit screen accessed from the control screen shown in FIG. 85.
FIG. 87 shows another exemplary control screen for operating the wake-modifying devices shown in the previous figures.
FIG. 88 shows a selection screen accessed from the control screen shown in FIG. 87.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Exemplary preferred embodiments of the invention will now be described with reference to the accompanying figures. Like reference numerals refer to the same or similar elements throughout the figures and description.
First Embodiment
FIGS. 3 and 4 show a boat 100 equipped with a pair of wake-modifying devices 111, 112 in accordance with a first preferred embodiment of the invention. The boat hull 120 includes a bow 121, a transom 122, and port and starboard sides 123, 124. Within the boat's interior is a control console 140 for operating the boat 100. The boat 100 is driven by a single inboard motor (not shown) connected to a left-handed propeller 170. However, the wake-modifying devices 111, 112 can be utilized with other types of boats and propulsion systems, including but not limited to right-handed propellers, outboard motors, sterndrives, and the like.
The boat 100 has a centerline 150 running down the center of the boat, halfway between the port and starboard sides 123, 124. A conventional trim tab 20 is pivotably attached to the transom 122 along the centerline 150. The wake-modifying devices 111, 112 are pivotably attached to the transom 122 on port and starboard sides of the centerline 150, respectively.
FIGS. 5-18 are detailed views of the wake-modifying device 111 on the port side of the boat 100. Similarly, FIGS. 19-30 are detailed views of the wake-modifying device 112 on the starboard side of the boat 100. While the port and starboard wake modifying-devices 111, 112 have many similar features in this embodiment, the port and starboard wake-modifying devices 111, 112 differ with respect to one downturned surface 330, which the port wake-modifying device 111 includes and the starboard wake-modifying device 112 lacks, as will be discussed further below. Except where noted otherwise, the discussion of the wake-modifying devices applies equally to both the port and starboard wake-modifying devices 111, 112.
Each wake-modifying device 111, 112 includes a plate-like member 200 that is pivotably attached to the transom 122 of the boat 100. The plate-like member 200 pivots about a pivot axis 210 to move between a non-deployed position and a deployed position. In this embodiment, the pivot axis 210 is a hinge and is flush with the transom 122 of the boat 100. Here, the hinge is a piano hinge that is welded to a leading portion L of the plate-like member 200 and attached to the transom of the boat 100 using screws. However, any suitable pivotable connection may be used and it may be affixed to the wake-modifying device 111, 112 and transom 122 of the boat 100 using any suitable means, including but not limited to bolts, screws, rivets, welding, and epoxy. In addition, the wake modifying device 111, 112 may be attached to the transom 122 such that the pivot axis 210 is not flush with the transom 122, for example, the pivot axis may be spaced further aft of the transom 122. The wake-modifying devices 111, 112 also may be attached to portions of the boat other than the transom 122. For example, the wake-modifying devices 111, 112 could be attached to the bottom of the hull 120, to the port and starboard sides 123, 124 of the hull 120, or to a swim platform (not shown). The pivot axis 210 preferably is parallel to the transom 122, but it may be oriented at an oblique angle relative to the transom 122 so long as the wake-modifying device 111, 112 provides an upward force on the boat 100 as the boat 100 travels forward through the water.
In the embodiment shown, the pivot axis 210 is parallel to the deadrise (the angle of the hull from the keel to the chine at the transom 122) of the boat 100. But the pivot axis 210 may instead be at an angle relative to the deadrise. Some boats, for example, have little or no deadrise. In such cases, it may be advantageous to orient the pivot axis 210 at an angle relative to the deadrise. Preferably, the pivot axis is inclined no more than about 35° from horizontal, more preferably no more than about 20° from horizontal, and most preferably no more than about 15° from horizontal. This inclination is preferably in the direction from the chine to the keel. Preferably, the pivot axis is inclined no more than about 15° more than the deadrise.
The plate-like member 200 has a trailing portion T that is aft of the leading portion L. The trailing portion T is the aft half of the plate-like member 200, and the leading portion L is the forward half of the plate-like member 200. The plate-like member 200 also has an inboard portion I and an outboard portion O. The inboard portion I is the inboard half of the plate-like member, and the outboard portion O is the outboard half of the plate-like member. Thus, the plate-like member may be divided into quadrants as shown in FIGS. 13 and 25: a leading, inboard portion L, I; a leading, outboard portion L, O; a trailing, inboard portion T, I; and a trailing, outboard portion T, O.
In the embodiment shown, there are two downturned surfaces 310, 320 at the trailing portion T of the plate-like member 200. The first downturned surface 310 intersects the plate-like member 200 along a line that is generally parallel to the pivot axis 210. The second downturned surface 320 intersects the plate-like member 200 along a line that is oriented at an angle α relative to the pivot axis 210. In this embodiment, the first downturned surface 310 is outboard of the second downturned surface 320, which is at the trailing, inboard portion T, I of the plate-like member 200. The second downturned surface 320 may extend into adjacent quadrants without deviating from the scope of the invention. The first and second downturned surfaces 310, 320 preferably are at the edge of the plate-like member 200, but they may be inward of the edge.
The inventors believe that the combination of the plate-like member 200 and one or both of the downturned surfaces 310, 320 improves the size and shape of the wake. The side of the boat 100 with the desirable wake is referred to as the surf side. The surf side is the side of the boat 100 opposite a deployed wake-modifying device. The side with the deployed wake-modifying device is referred to as the non-surf side.
As the boat 100 moves through the water, the hull displaces water both downward under the hull 120 and outward of the sides 123, 124 of the hull 120. This creates a cavity immediately behind the boat 100. The displaced water recovers behind the boat 100 to fill the cavity. As the displaced water recovers, the water converges from under the boat 100 and from the sides 123, 124 of the hull 120. When the convergence occurs with sufficient force, it creates a v-shaped wave crest or “rooster tail” at the point of convergence. This v-shaped crest then propagates outward behind the boat 100 creating a wake that is suitable for wakeboarding, wake surfing, and the like. When one of the wake-modifying devices 111, 112 is in the deployed position, the downturned surfaces 310, 320 direct the water sharply downward. This sharp redirection of water results in an additional upward force to roll the boat 100 toward the surf side to a greater degree than the prior art trim tabs discussed above and shown in FIGS. 1 and 2. As a result, the boat 100 displaces more water on the surf side creating a more desirable wake for surfing. The inventors have found that shifting the point of convergence aft of the transom 122 and toward the non-surf side will also improve the wake on the surf side. The inventors believe that creating a trough in the water behind the deployed wake-modifying device and delaying the water from recovering from the non-surf side shifts the convergence point aft of the transom 122 and toward the non-surf side. The downturned surfaces 310, 320 are believed to contribute to both of these actions. The angles of the downturned surfaces and the size of the plate contribute to the timing of water recovery to increase the size of the wake on the surf side as a result of wave superposition.
The downturned surface 310, 320 should extend far enough in a downward direction to cause redirection of the water. The downturned surface 310, 320 should also be short enough that the downturned surface does not interact with the water when in the non-deployed position. Preferably, the downturned surface 310, 320 extends from about 1 inch to about 21⁄4 inches below a lower surface 220 of the plate-like member 200, and more preferably about 11⁄2 inches below the lower surface 220 of the plate-like member 200. The downturned surface 310, 320 forms an angle β with a lower surface 220 of a central portion of the plate-like member 200. The inventors have found that this angle β should be sufficient to redirect the water, but not so sharp as to result in excessive force on the wake-modifying device 111, 112. Preferably, the angle β between the downturned surface 310, 320 the lower surface 220 of the central portion of the plate-like member 200 is between about 120° and about 135°.
The water converging behind the boat 100 from the sides 123, 124 of the hull 120 forms an angle with the sides of the hull 123, 124. The inventors have found that orienting a downturned surface 320 to intersect this angle improves the wake on the surf side. Accordingly, the line where the second downturned surface 320 intersects the plate-like member 200 is oriented at an angle α relative to the pivot axis 210. This angle α preferably is perpendicular to the angle formed between the recovering water and the side 123, 124 of the hull 120. The angle α preferably is between about 30° to about 45°.
In the embodiment shown, the wake-modifying device 111, 112 has two upturned surfaces 410, 420 between the first downturned surface 310 and the pivot axis 210. These upturned surfaces 410, 420 are at the outboard portion O of the plate-like member 200, preferably at the edge of the plate-like member, but they may be inward of the edge. An angle γ between the upturned surfaces 410, 420 and an upper surface 230 of the central portion of the plate-like member 200 preferably is between about 30° to about 150°, and more preferably is about 90°. The inventors believe that these upturned surfaces 410, 420 delay the water on the non-surf side from converging behind the boat 100 and further shift the point of convergence aft of the transom 122 and toward the non-surf side. The upturned surfaces 410, 420 should extend far enough in an upward direction to delay the water. The upturned surfaces 410, 420 preferably extend at least about 1 inch above the upper surface 230 of the plate-like member 200, more preferably at least about 2 inches above the upper surface 230 of the plate-like member 200, and even more preferably at least about 2.5 inches above the upper surface 230 of the plate-like member 200. In this embodiment, the first upturned surface 410 intersects the plate-like member along a line that is generally parallel to either the port side 123 of the hull 120 or the starboard side 124 of the hull 120. The second upturned surface 420 is positioned between the first upturned surface 410 and the first downturned surface 310 and intersects the plate-like member along a line that is oriented at an oblique angle δ with respect to the pivot axis 210. The angle δ preferably is between about 60° to about 90°, and more preferably is about 75°.
A third downturned surface 330 between the second downturned surface 320 and the pivot axis 210 can further improve the wake on the surf-side. An angle ε between the third downturned surface 330 and the lower surface 220 of the central portion of the plate-like member 200 preferably is between about 30° to about 150°, and more preferably is about 90°. The inventors believe this third downturned surface 330 further delays the water on the non-surf side from converging with the water on the surf side. In the embodiment shown, the third downturned surface 330 is positioned along the inboard portion I of the plate-like member 200 and intersects the plate-like member 200 along a line that is generally perpendicular to the pivot axis 210. The third downturned surface 330 preferably is at an inboard edge of the plate-like member, but it may be inward of the edge. Similar to the other downturned surfaces 310, 320, the third downturned surface 330 should extend far enough in a downward direction to delay or redirect the water. As with the other downturned surfaces 310, 320, the third downturned surface 330 is preferably short enough that the third downturned surface 330 does not interact (or at least minimizes interaction) with the water when in the non-deployed position. The third downturned surface 330 preferably extends between about 1⁄2 inch to about 3 inches below the lower surface 220 of the plate-like member 200, and more preferably extends about 1 inch below the lower surface 220 of the plate-like member 200.
The boat 100 of this embodiment uses a left-handed propeller 170, which causes the prop wash to be offset towards the starboard side. To balance the desirability of the surf wakes on both sides of the boat 100, the port wake-modifying device 111 of this embodiment provides more delay of the water than does the starboard wake-modifying device 112. In this embodiment, the port wake-modifying device 111 has the third downturned surface 330 while the starboard wake-modifying device 112 does not. However, the third downturned surface 330 may be provided on either the port or starboard wake-modifying device 111, 112, both, or neither.
FIG. 16 shows the port wake-modifying device 111 in a non-deployed position, and FIG. 17 shows the port wake-modifying device 111 in a deployed position. Similarly, FIG. 28 shows the starboard wake-modifying device 112 in a non-deployed position, and FIG. 29 shows the starboard wake-modifying device 112 in a deployed position. As water recovers from under the boat, it travels at an upward angle. The angle of water recovery will depend on a number of factors including hull design and operational parameters, for example, speed. In the non-deployed position, the wake-modifying device 111, 112 preferably is at an upward angle so that it does not interact with the recovering water. The wake-modifying device 111, 112 is moved from the non-deployed position to a deployed position by pivoting about the pivot axis 210. In the deployed position, the trailing portion T of the wake-modifying device 111, 112 is lower than it is in the non-deployed position. The deployed position preferably is even with the bottom of the hull and more preferably extends at a downward angle ζ, as shown in FIGS. 17 and 29. As discussed above, the wake-modifying device 111, 112 may be pivotable about an axis that is not horizontal, for example, it may be at an angle parallel to the deadrise. The deployed position is not limited to a single angle ζ, but rather may vary depending upon the preferences of the water sports performer. In this embodiment, the angle ζ is directly proportional to the size of the wake, but as the angle ζ gets larger, the wake begins to break (curl over) closer to the boat 100, reducing the area on the wake that is desirable for surfing. In this embodiment, the angle ζ preferably is between about 0° and about 12°.
In the embodiment shown, a linear actuator 510 is used to move the wake-modifying device 111, 112 between the deployed and non-deployed positions. The linear actuator 510 preferably is an electric linear actuator, such as one available from Lenco Marine. One end of the linear actuator 510 is screwed to the transom 122 of the boat 100. The other end of the linear actuator is connected to a u-shaped bracket 202 by a pin 204. The u-shaped bracket 202 is then bolted to the plate-like member 200. Any suitable means may be used to move the wake-modifying device 111, 112 between the deployed and non-deployed positions, including but not limited to hydraulic linear actuators and mechanical levers.
The size of the wake-modifying device 111, 112 may be varied depending upon the characteristics of the boat 100 and the desired wake. The lift provided by the wake-modifying device 111, 112 is generally proportional to the angles α, β, the surface area of the first and second downturned surfaces 310, 320, and the surface area of the plate-like member 200. In this embodiment, the wake-modifying device 111, 112 is about 17 inches long and about 14.5 inches wide. Preferably, the wake-modifying device 111, 112 is at least about 10 inches long and at least about 9 inches wide.
Because the wake-modifying device 111, 112 is used in a marine environment, it preferably is made of materials suitable for that environment. In this embodiment, these materials are primarily corrosion-resistant metal alloys such as stainless steel. The wake-modifying device 111, 112, including the plate-like member 200, preferably should not deform during operation. Preferably, the wake-modifying device 111, 112 will have sufficient rigidity to maintain its shape at all speeds and especially at speeds suitable for surfing (approximately 9 mph to 12 mph). In the preferred embodiment, the wake-modifying device 111, 112 is made from 12 gauge stainless steel plate. Other suitable materials may be used instead, such as wood, plastic, fiber reinforced composites, or other metals including aluminum.
FIGS. 18 and 30 show manufacturing views of the port and starboard wake-modifying devices 111, 112, respectively. The wake-modifying device 111, 112 may be manufactured by cutting the device from a single plate stock to the desired shape and then bending the downturned and upturned surfaces to the desired angles. In this embodiment, the plate-like member 200, the downturned surfaces 310, 320, 330, and the upturned surfaces 410, 420 are an integral piece. Alternatively, some or all of the downturned and upturned surfaces may be formed as separate pieces and then attached to the plate-like member using any suitable joining method such as welding, bolting, riveting, or the like.
Second Embodiment
Boat design plays an important role in establishing the wake shape. Design factors include, for example, the hull design and the weight of the boat. The wake-modifying device 111, 112 preferably is customized based on the boat design in order to produce the desired wake.
As an example of how hull design affects the boat's wake, a first boat having a steeper deadrise than a second boat will typically allow the water to recover closer to the transom of the boat. The shape of the corners between the sides of the hull and the transom also impact the recovery of the water. A boat with smooth corners (e.g., having a radius) will allow the water to recover faster than will a boat with square corners. The wake-modifying devices 111, 112 of the second embodiment are designed to provide greater lift to the boat on the non-surf side and further delay and direct the water on the non-surf side.
FIG. 31 shows a stern view of a boat 100 equipped with wake-modifying devices 111, 112 according to a second preferred embodiment of the invention. The port wake-modifying device 111 of the second embodiment is shown in FIGS. 32-45. The starboard wake-modifying device 112 of the second embodiment is shown in FIGS. 46-57.
As with the first embodiment, the port and starboard wake-modifying devices 111, 112 of the second embodiment are not symmetrical with one another. Here, the port wake-modifying device 111 includes two fins 340, 350 attached to the lower surface 220 of the plate-like member 200. These fins 340, 350 extend at a downward angle η relative to the lower surface 220 of the plate-like member 200. The downward angle η preferably is between about 30° and about 150°, and more preferably is about 90°. The fins 340, 350 intersect the plate-like member 200 along lines that are oriented at an angle θ relative to the pivot axis 210. This angle θ preferably is between about 15° and about 75°, and more preferably is between about 30° and about 60°. In the embodiment shown, the fins 340, 350 are parallel to each other and at an angle θ of 60° relative to the pivot axis 210. The inventors believe these fins 340, 350 redirect the water outboard, further shifting the point of convergence aft from the transom 122 and toward the non-surf side. As with the downturned surfaces 310, 320, 330 and the upturned surfaces 410, 420, the fins 340, 350 should extend far enough away from the plate-like member 200 to redirect the water flow. The fins 340, 350 preferably should extend at least about 1 inch below the lower surface 220 of the plate-like member 200, and more preferably should extend at least about 2 inches below the lower surface 220 of the plate-like member 200. In the embodiment shown, the fins 340, 350 have different lengths. The fins preferably are about 4 inches to about 16 inches long, and more preferably are about 8 inches to about 12 inches long. The fins preferably do not extend beyond the edges of the plate-like member.
In the second embodiment, the third downturned surface 330 intersects the plate-like member along a line that is oriented at an oblique angle φ relative to the pivot axis 210. The angle φ preferably is between about 45° to about 90°, and more preferably is about 70°. All three of the downturned surfaces 310, 320, 330 form an angle α, ε with respect to the lower surface 220 of the central portion of the plate-like member 200 of about 135°. The wake-modifying devices 111, 112 of this embodiment preferably are about 17 inches wide and about 16 and 1⁄2 inches long.
Third Embodiment
The port and starboard wake-modifying devices 111, 112 in the previous two embodiments are asymmetrical with each other, but the wake-modifying devices 111, 112 can be symmetrical. Symmetrical wake-modifying devices 111, 112 may be used, for example, with heavy boats where the propeller 170 has less of an impact on the boat's wake. The third preferred embodiment shown in FIGS. 58-84 is an example of a symmetrical pair of wake-modifying devices 111, 112. FIG. 58 shows a stern view of a boat 100 equipped with wake-modifying devices 111, 112 according to a third embodiment of the invention. The port wake-modifying device 111 of the third embodiment is shown in FIGS. 59-72. The starboard wake-modifying device 112 of the third embodiment is shown in FIGS. 73-84. In this embodiment, both the port and starboard wake-modifying devices 111, 112 have two fins 340, 350. In the embodiment shown, the fins 340, 350 are parallel to each other and oriented at an angle θ of 45° relative to the pivot axis 210.
Control System
Those skilled in the art understand that the weight and displacement of the boat has a significant impact on the size and shape of the wake. As a result, many recreational sport boats that are used for wakeboarding and wake surfing accommodate additional weight or ballast. In particular, many boats are designed to have ballast added to the surf side of the boat to increase the displacement of that side of the boat. This weight may be added by any number of ways known to those skilled in the art. One way is to position more people on the surf side of the boat than on the non-surf side. Another way is to add ballast through the use of ballast bags or ballast sacks. Yet another way to add weight is through ballast tanks installed in the boat. Preferably, two ballast tanks are positioned in the stern of the boat near the bottom of the hull, one on each side of the boat, and a third ballast tank is positioned along the boat's centerline near the bottom of the hull, forward of the two rear ballast tanks. If ballast bags are used in addition to ballast tanks, the ballast bags may be plumbed into the ballast system of the boat. Both the ballast tanks and the ballast bags operate similarly in that water may be pumped into the tank or bag by ballast pumps to add weight. In some boats, both ballast tanks and ballast bags may be used simultaneously. For example, all three ballast tanks may be filled to increase the displacement of the stern of the boat, and a ballast bag on the surf side of the boat may be filled to further increase the displacement on the surf side.
A control system is used to operate the wake-modifying devices 111, 112. When the wake-modifying devices 111, 112 are used with plumbed-in ballast, the control system preferably controls both the ballast and the wake-modifying devices 111, 112. This control system preferably includes a controller that controls the linear actuators 510 and the ballast pumps. The controller may be any suitable controller known in the art including a controller comprising a CPU, ROM, and RAM. The control system also includes an input device. In the preferred embodiment, the input device is a touch screen located at the control console 140 of the boat 100. Also in this embodiment, the controller is co-located with the touch screen. Those skilled in the art will recognize that any suitable input device including buttons, switches, dials, or the like may be used.
An exemplary touch screen 610 is shown in FIG. 85. This touch screen 610 is shown in a manual mode. In this mode, a user can manually adjust the amount of water in the ballast tanks and manually adjust the percentage of deployment of the wake-modifying devices 111, 112. To adjust ballast, the user selects the “BALLAST” button 611. To adjust the deployment of the wake-modifying devices or center trim tab, the user selects the “TABS” button 612. To adjust the speed of the boat, the user selects the “SET SPEED” button 613. When one of these buttons is selected, a new screen is displayed that allows the user to adjust the selected parameter. When the user selects the “TABS” button 612, for example, an “EDIT TABS” screen 620 is displayed as shown in FIG. 86. On this screen 620, the user may adjust the percentage deployment of the wake-modifying devices 111, 112 and/or the center trim tab 20. To deploy the port wake-modifying device 111, for example, a user swipes his or her finger in direction A in the area 621 until the desired percentage deployment (50 percent in the example shown) is reached. Alternatively, the user may use adjustment arrows 622 to incrementally change the percentage deployment. When the percentage deployment of the port wake-modifying device 111 is changed, the controller drives the linear actuator 510 of the port wake-modifying device 111 to move the port wake-modifying device 111 to the set position. The starboard wake-modifying device 112 and the center trim tab 20 are adjusted in the same manner.
As another option, the wake-modifying devices, ballast, and boat speed may be controlled using user-defined programmed settings. A user can manually set each of the parameters in the manual mode as described above and then save these settings as a user-defined profile. In operation, a touch location 610, shown in FIG. 85, may be used to toggle between these user-defined programmed settings. In this embodiment, a user toggles between settings by swiping touch position 614 to the left or right.
In addition to or instead of the foregoing, the control system can include preprogrammed settings established by the boat manufacturer. After one of the preprogrammed settings has been selected by a user, a cruise control screen 630 may be displayed, such as shown in FIG. 87. The boat may be set to cruise at a specific speed by selecting the “ON” button 632. If the user desires to switch between preprogrammed settings, the user may select the “SWITCH” button 631. Selecting the “SWITCH” button 631 causes a pop-up window to be displayed within the control screen 640, such as shown in FIG. 88. Using the pop-up window the user may select a different preprogrammed setting. In this embodiment, four preprogrammed settings are shown. The two “mellow” settings (“SURF LEFT MELLOW” 641 and “SURF RIGHT MELLOW” 643) may be programmed such that the controller drives the linear actuator 510 to deploy the wake-modifying device 111, 112 on the non-surf side to a relatively shallow deployed position. The two “steep” settings (“SURF LEFT STEEP” 642 and “SURF RIGHT STEEP” 644) may be programmed to maximize the size of the wake. In these “steep” settings, the controller drives the linear actuator 510 to deploy the wake-modifying device 111, 112 on the non-surf side to the maximum deployed position. In addition to or instead of a touch screen, other known input devices, such as static buttons 650, can be used.
The embodiments described and shown herein are examples of preferred embodiments of the present invention and are provided for illustrative purposes only. They are not intended to limit the scope of the invention. Although specific configurations, structures, materials, etc. have been shown and described, such are not limiting. Modifications and variations are contemplated within the scope of the invention, which is to be limited only by the scope of the claims.

## Claims

1. A recreational sport boat comprising:
a hull including starboard and port sides and a transom; and
a pair of wake-modifying devices positioned aft of the transom, one of the wake-modifying devices being positioned on a port side of the boat's centerline and another of the wake-modifying devices being positioned on a starboard side of the boat's centerline, each wake-modifying device being pivotable between a non-deployed position and a deployed position about a pivot axis that is horizontal or inclined no more than about 35° from horizontal, each wake-modifying device including:
a plate-like member; and
at least two downturned surfaces at a trailing portion of the plate-like member, a first one of the downturned surfaces being generally parallel to the pivot axis, and a second one of the downturned surfaces being at an obtuse angle relative to the first downturned surface,

wherein in the deployed position, the first and second downturned surfaces are lower than they are in the non-deployed position so as to be able to modify the boat's wake.

2. The recreational sport boat of claim 1, wherein each wake-modifying device is pivotably attached directly to the transom.

3. The recreational sport boat of claim 1, wherein the plate-like member, the first downturned surface, and the second downturned surface of each wake-modifying device are an integral piece.

4. The recreational sport boat of claim 1, wherein the plate-like member, the first downturned surface, and the second downturned surface of each wake-modifying device are separate pieces joined together.

5. The recreational sport boat of claim 1, wherein at least one of the first and second downturned surfaces of each wake-modifying device is at a trailing edge of the plate-like member.

6. The recreational sport boat of claim 1, wherein an angle between each of the first and second downturned surfaces of each wake-modifying device and a lower surface of a central portion of the plate-like member is between about 120° to about 135°.

7. The recreational sport boat of claim 1, wherein each of the first and second downturned surfaces of each wake-modifying device extends between about 1 inch to about21⁄4 inches below a lower surface of the plate-like member.

8. The recreational sport boat of claim 1, wherein the obtuse angle is between about 135° to about 150°.

9. The recreational sport boat of claim 1, wherein the first downturned surface is outboard of the second downturned surface for each wake-modifying device.

10. The recreational sport boat of claim 1, wherein each wake-modifying device further includes at least one upturned surface at an outboard portion of the plate-like member, between the first downturned surface and the pivot axis.

11. The recreational sport boat of claim 10, wherein the plate-like member and the upturned surface of each wake-modifying device are an integral piece.

12. The recreational sport boat of claim 10, wherein the plate-like member and the upturned surface of each wake-modifying device are separate pieces joined together.

13. The recreational sport boat of claim 10, wherein an angle between the upturned surface of each wake-modifying device and an upper surface of a central portion of the plate-like member is about 90°.

14. The recreational sport boat of claim 10, wherein the upturned surface of each wake-modifying device extends at least about 1 inch above an upper surface of the plate-like member.

15. The recreational sport boat of claim 1, wherein at least one of the wake-modifying devices includes at least three downturned surfaces, a third one of the downturned surfaces being at an inboard portion of the plate-like member, between the first downturned surface and the pivot axis.

16. The recreational sport boat of claim 15, wherein an angle between the third downturned surface and a lower surface of a central portion of the plate-like member of each wake-modifying device is between about 30° to about 150°.

17. The recreational sport boat of claim 16, wherein the angle between the third downturned surface and the lower surface of the central portion of the plate-like member is about 90°.

18. The recreational sport boat of claim 1, wherein at least one of the wake-modifying devices further includes at least one fin attached to a lower surface of the plate-like member.

19. The recreational sport boat of claim 18, wherein the fin is at an angle between about 15° and about 75° relative to the pivot axis and extends in a direction aft and outboard from the pivot axis.

20. The recreational sport boat of claim 19, wherein the fin is at an angle between about 30° and about 60° relative to the pivot axis.

21. The recreational sport boat of claim 1, wherein at least one of the wake-modifying devices includes at least two fins attached to a lower surface of the plate-like member, and the fins are parallel to each other.

22. The recreational sport boat of claim 1, wherein the wake-modifying devices are asymmetrical with each other.

23. The recreational sport boat of claim 1, wherein each wake-modifying device is capable of assuming multiple deployed positions, and in each different deployed position the wake-modifying device is pivoted downwardly at a different angle relative to the non-deployed position.

24. The recreational sport boat of claim 1, further comprising a pair of linear actuators, each linear actuator being operable to move a respective one of the wake-modifying devices between its non-deployed position and its deployed position.

25. A recreational sport boat comprising:
a hull including starboard and port sides and a transom; and
a pair of wake-modifying devices pivotably attached to the transom, one of the wake-modifying devices being positioned on a port side of the boat's centerline and another of the wake-modifying devices being positioned on a starboard side of the boat's centerline, each wake-modifying device being pivotable between a non-deployed position and a deployed position about a pivot axis that is horizontal or inclined no more than about 35° from horizontal, each wake-modifying device including:
a plate-like member;
at least two downturned surfaces at a trailing portion of the plate-like member, a first one of the downturned surfaces being generally parallel to the pivot axis, and a second one of the downturned surfaces being at an obtuse angle relative to the first downturned surface, with the first downturned surface being outboard of the second downturned surface; and
at least one upturned surface at an outboard portion of the plate-like member, between the first downturned surface and the pivot axis,

wherein an angle between each of the first and second downturned surfaces and a lower surface and a central portion of the plate-like member is between about 120° to about 135°, and an angle between the upturned surface and an upper surface of the central portion of the plate-like member is about 90°, and
wherein in the deployed position, the first and second downturned surfaces are lower than they are in the non-deployed position so as to be able to modify the boat's wake.

26. The recreational sport boat of claim 25, wherein at least one of the wake-modifying devices further includes a third downturned surface at an inboard portion of the plate-like member, between the second downturned surface and the pivot axis, and an angle between the third downturned surface and the lower surface of the central portion of the plate-like member is about 90°.

27. The recreational sport boat of claim 25, wherein at least one of the wake-modifying devices further includes one or more fins attached to the lower surface of the plate-like member.