US20210070406A1 - Lateral displacement surf system - Google Patents

Abstract

The present disclosure generally pertains to a lateral displacement surf system and methods of laterally displacing a watercraft to generate wake. The lateral displacement system includes at least one pair of foils configured to be extended from a hull on a first side of the watercraft at a level of approximately the waterline. Upon forward movement of the watercraft with extended foils, the watercraft is rotated about its vertical axis toward the first side and generates waves sufficient for the conduction watersport activities on a second side of the watercraft. In some instances, foils are built into the hull and extended from this position, while in other instances the foils are attached to the hull using attachment structures. Rotation of the foils about an axis of rotation approximately perpendicular to a longitudinal axis of the watercraft alters the angle of attack of the foils relative to the waterline.

Description

RELATED REFERENCES
• This application claims benefit to U.S. Provisional Application No. 62/897,578 filed on Sep. 9, 2019, titled “Hydrofoil System And Methods of Using Same” and U.S. Provisional Application No. 62/923,281, filed on Oct. 18, 2019, titled “Lateral Displacement Surf System,” the entire contents of which are incorporated herein.
TECHNICAL FIELD
• The present invention is directed to a surf system for use with watercrafts to generate lateral displacement of the watercrafts and provide surf suitable for the practice of various watersports.
BACKGROUND OF INVENTION
• The practice and enjoyment of many watersports relies on the generation of wake of an appropriate size, shape, and position relative to a watercraft. These wake requirements often vary with different watersports and according to the participant's skill level, size, and preference. For example, an acceptable “surf wave” may be inappropriate or unusable for other activities, such as water-skiing or tubing. Thus, an operator of the watercraft generally desires to adjust wake as appropriate for the intended watersport and watersport participant.
• One method of wake adjustment is through the use of a weighted ballast system, which results in an increase in the displacement of water due to increases in the weight of the watercraft. Displaced water is generally equal to the weight of the object that is floating or submerged in the water, so that more displacement results in a larger wave. A weighted ballast system typically includes bags that are filled with water, lead weights, or, less commonly, sand. Deployment, retraction, and adjustments to ballast systems are often time-consuming, inconvenient, and hinder the ability of the watercraft operator to quickly configure the watercraft for different watersports or participants.
• The present invention presents a surf system that provides and alters wake by displacing watercrafts laterally, rather than the general downward displacement created by weighted ballast systems. In such a laterally-displaced system, the watercraft is put into a slight “yaw” position where the watercraft is pulled and rotated toward a non-surf side of the watercraft, allowing the hull to enter the water about approximately the entire length of the surf side of the watercraft, creating surf from the surf-side. By deploying or placing hydrofoils or wings on the non-surf side of the watercraft, lateral displacement is induced during watercraft movement and wake is generated. The lateral displacement surf system of the present disclosure thus generates wake through positioning and orientation of hydrofoils or wings, and wake may be quickly altered through their repositioning or reorientation, providing flexibility to a watersport participant.
SUMMARY OF THE INVENTION
• The present invention is directed to a lateral displacement surf system and methods of using same. In one aspect, there is provided a lateral displacement system for generating waves. The lateral displacement system includes at least one pair of foils, each foil having a base with a front surface and a back surface, a curved wing, and an angled wing support connecting the curved wing to the front surface of the base at a wing angle. The base has at least one attachment structure on the back surface configured to attach the foil to a hull of a watercraft. Suitable attachment structures include suction cups, adhesives, and hook and pile systems, as well as systems that include mechanisms integrally formed with the hull of the watercraft including, for example, magnetic structure systems like those described in U.S. Pat. Nos. 7,843,296, 7,843,295, 8,339,226, 8,354,909, 8,373,527, 8,373,527, 8,395,467, 8,536,966, 8,698,583 and 9,105,380. Thus, when the at least one pair of foils is attached to the watercraft on a first side at a level of approximately a waterline, forward movement of the watercraft in water causes rotation of the watercraft about its vertical axis, i.e., yaw axis and generates waves sufficient for the conduction watersport activities on a second side of the watercraft. These waves exit at a rear end of the watercraft. Exemplary watercraft include powered personal watercraft such as those manufactured by Sea-Doo and Yamaha's WaveRunner-branded personal watercraft, skiffs, bass boats, ski boats, deck boats, boats that exclude or that include automatic water ballast systems, boats that exclude or include removable water bladders as ballast, sail-propelled boats, trawlers and center console boats.
• To generate waves sufficient for use in watersport activities, a rear foil of the at least one pair of foils is positioned along the first side of the watercraft approximately 18 inches to approximately 36 inches from a transom of the watercraft. A front foil of the at least one pair of foils is positioned along the first side of the watercraft nearer a bow than the rear foil and the front foil is approximately 60 percent of a size of the rear foil. To maximize yaw of the watercraft, the front foil is positioned forward of the center of gravity of the watercraft, and thus, a primary function of the front foil is to cause yawing of the watercraft. To enable secure attachment of the lateral displacement system, the base is flexible and is configured to place each of the at least one attachment structures in sufficient contact with the hull for attachment to the hull.
• The lateral displacement system further includes a fin mounted to the curved wing with a largest fin surface oriented approximately perpendicular to a largest curved wing surface, such that the largest fin surface is configured to be approximately parallel to the waterline when the foil is attached to the watercraft. This largest fin surface is cambered in some instances. To provide means of altering an angle of attack relative to the waterline, the curved wing is configured for movement relative to the base while the base is attached to the hull of the watercraft. This movement includes rotation of the curved wing about an axis of rotation that is approximately perpendicular to the base.
• In another aspect, a second embodiment of a lateral displacement system for generating waves is provided. This second embodiment includes at least one pair of cambered wings, each wing having an upper cambered surface and a lower cambered surface, wherein the at least one pair of cambered wings is configured for extension from a hull of a watercraft. When the at least one pair of cambered wings is extended from the watercraft on a first side at a level of approximately a waterline, forward movement of the watercraft in water causes rotation of the watercraft about its vertical axis toward the first side and generates waves sufficient for the conduction watersport activities on a second side of the watercraft. These waves exit at a rear end of the watercraft.
• To generate waves sufficient for use in watersport activities, a rear wing of the at least one pair of cambered wings is positioned along the first side of the watercraft approximately 18 inches to approximately 36 inches from transom of the watercraft. A front wing of the at least one pair of cambered wings is positioned along the first side nearer a bow of the watercraft than the rear wing and preferably forward of the center of gravity of the watercraft.
• In some instances, the at least one pair of cambered wings is built into the watercraft and configured to be extended and retracted from the hull of the watercraft, where the extension and retraction of the at least one pair of cambered wings may be automated. To adjust an angle of attack of the at least one pair of cambered wings relative to the waterline, the at least one pair of cambered wings is configured for rotation about an axis of rotation that is approximately perpendicular to a longitudinal axis of the watercraft.
• In other instances, the extension of at least one pair of cambered wings from the hull is accomplished by attaching at least one pair of cambered wings to a surface of the hull of the watercraft using at least one wing attachment structure on the at least one pair of cambered wings. To adjust an angle of attack of the at least one pair of cambered wings relative to the waterline, the at least one pair of cambered wings is configured for rotation about an axis of rotation that is approximately perpendicular to the longitudinal axis of the watercraft.
• According to yet another aspect of the invention, there is provided a method of generating waves using lateral displacement of a watercraft. The method includes a first step of providing a watercraft and a lateral displacement system, where the system including at least one pair of foils. The at least one pair of foils are extended from a hull on a first side of the watercraft at a level of approximately a waterline. Following extension of the at least one pair of foils, the watercraft is moved forward in the water so that the watercraft is rotated about its vertical axis toward the first side and generates waves sufficient for the conduction watersport activities on a second side of the watercraft. These waves exit at a rear end of the watercraft.
• In some instances, the extending is accomplished by attaching at least one pair of foils to a surface of the hull of the watercraft using at least one attachment structure on the at least one pair of foils. Rotating each foil of the at least one pair of foils about an axis of rotation that is approximately perpendicular to a longitudinal axis of the watercraft alters an angle of attack of each foil relative to a waterline. In other instances, the at least one pair of foils is built into the watercraft. Rotating each foil of the at least one pair of foils about an axis of rotation that is approximately perpendicular to the longitudinal axis of the watercraft alters an angle of attack of each foil relative to the waterline.
• In yet another aspect of the invention, there is provided a lateral displacement system for generating waves with watercraft that include an integrally transom-mounted wing or foil, for example, as described in U.S. Pat. Nos. 7,140,318, 8,539,897, 8,578,873, 9,580,147 and 10,322,777. The lateral displacement system includes a single foil having a base with a front surface and a back surface, a curved wing, and an angled wing support connecting the curved wing to the front surface of the base at a wing angle. The base has at least one attachment structure on the back surface configured to attach the foil to a hull of a watercraft. When the single foil is attached to the watercraft on a first side, forward of the center of gravity of the watercraft and at a level of approximately a waterline, forward movement of the watercraft in water causes rotation of the watercraft about its vertical axis toward the first side, i.e., yaw, and generates waves sufficient for the conduction watersport activities on a second side of the watercraft.
• A further understanding of the nature and advantages of the present invention will be realized by reference to the remaining portions of the specification and the drawings.
BRIEF DESCRIPTION OF DRAWINGS
• The lateral displacement surf system and method of using same can be better understood, by way of example only, with reference to the following drawings. The elements of the drawings are not necessarily to scale relative to each other, emphasis instead being placed upon clearly illustrating the principles of the disclosure. Furthermore, like reference numerals designate corresponding parts throughout the several views.
• FIG. 1A-B is one embodiment of a lateral displacement system showing a pair of foils for mounting onto a watercraft and generating waves. The view is A) a front perspective view and B) a back perspective view of the foils.
• FIG. 2 is a side elevational view of the lateral displacement system ofFIG. 1A-B, with wing angles visible.
• FIG. 3A-C are perspective views of a rotatable foil embodiment of the lateral displacement system ofFIG. 1A-B. Foils start in A) an initial position, are then B) rotated about at an intersection of their angled wing support and bases, and C) fixed in a second position that is different from the initial position.
• FIG. 4A-B are perspective views of foils of the lateral displacement system ofFIG. 1A-B attached to the hull of a watercraft from A) a front-side perspective view and B) a rear-side perspective view.
• FIG. 5A-B are perspective and elevational views of a fin attached to the curved wing of the lateral displacement system ofFIG. 1A-B. The finned version is shown from A) a perspective view and B) a front elevational view.
• FIG. 6A-B are perspective views of a fin attached to the curved wing of the lateral displacement system ofFIG. 1A-B. The finned version is shown attached A) from a level of an intended waterline from a side perspective view of the watercraft and B) as would be viewed from a bow of a watercraft looking toward a stern of the watercraft in a front perspective view.
• FIG. 7 is a top view of the lateral displacement system ofFIG. 1A-B on a first side of a watercraft.
• FIG. 8 is a side view of the lateral displacement system ofFIG. 1A-B when attached to the hull of a watercraft when the watercraft is unpowered.
• FIG. 9 is a back perspective view of attachment structures on the bases of the pair of foils from the lateral displacement system ofFIG. 1A-B.
• FIG. 10 is a side view of the lateral displacement system ofFIG. 1A-B when attached to the hull of a watercraft when the watercraft is powered.
• FIG. 11 is a side view of rotation of a watercraft with the lateral displacement system ofFIG. 1A-B about a vertical “yaw” axis to generate waves.
• FIG. 12 is a perspective view of a second embodiment of the lateral displacement system ofFIG. 1A-B with foils having a cambered wing shape.
• FIG. 13 is bottom view of the second embodiment of the lateral displacement system ofFIG. 1A-B.
• FIG. 14A-B are perspective and elevational views of the second embodiment of the lateral displacement system ofFIG. 1A-B with foils having a cambered wing shape. The cambered wing is shown from A) a top-side perspective view and B) a side elevational view.
• FIG. 15A-B are side views of the second embodiment of the lateral displacement system ofFIG. 1A-B attached to a watercraft. The cambered wings are attached and shown in A) a view depicting the entirety of the watercraft and B) a section of the watercraft where the cambered wings are attached.
• FIG. 16 is a top view of the second embodiment of the lateral displacement system ofFIG. 1A-B where cambered wings are controlled, regarding extension and rotation, from the interior of the watercraft.
DETAILED DESCRIPTION OF THE INVENTION
• The present invention is generally directed to a lateral displacement system for the generation of waves suitable for the enjoyment of watersport activities.Lateral displacement system10 is configured to be attached to awatercraft14, so thatwatercraft14 generates waves or wake sufficient for the enjoyment of watersports, such as wakeboarding and surfing. Wake characteristics or size are enhanced bylateral displacement system10 by allowing control of wave steepness, length, and other such wave characteristics. At least one pair offoils12 oflateral displacement system10 are configured to be attached to watercraft14 at least at two points onwatercraft14, where attachment may be permanent or temporary as appropriate per application. Attachment methods and positions oflateral displacement system10 are detailed below.
• As used herein, a “foil” is an aerodynamic shape or structure that creates lift through movement through a fluid medium. When that medium is water, it is known as a hydrofoil. A wing or a cambered wing is considered to be a foil, for example. Publically available foil designs contemplated by the present disclosure are available at m-selig.ae.illinois.edu/ads/coord_database.html. No particular one of the publically available designs are necessary for success of the present disclosed invention and methods. The terms “foil” and “wing” are used interchangeably in the present disclosure.
• As used herein, “forward movement” refers to movement that is at least partially directed toward the direction that the bow or front of the watercraft is facing. This movement may be relative to the flow of water about a watercraft.
• As used herein, a “leading edge” is a location on the foil where the upper camber and lower camber meet, and is the closest edge in the direction that the foil is traveling.
• As used herein, “lift” is not an absolute direction; rather it is a force that is the result of a foil moving through a fluid medium. Lift may be generated in any direction, depending on the orientation of the leading edge of the foil relative to the direction of motion through the fluid.
• Inlateral displacement system10, at least one pair offoils12 is positioned on a non-surf side ofwatercraft14 so thatwatercraft14 is in a “yaw” position when in forward motion. This positioning rotates or revolveswatercraft14 along avertical axis16 ofwatercraft14, where a pull towards the non-surf side allows the hull ofwatercraft14 to enter the water for approximately the length of the surf side. The surf side is opposite the non-surf side, so that when the at least one pair offoils12 is placed on a starboard side, the starboard side is the non-surf side and a port side is the surf side. Similarly, when the at least one pair offoils12 is placed on the port side, the port side is the non-surf side and the starboard side is the surf side. Surf, wake, or waves generated using lateral displacement system exit from approximately the rear, back, or stern42 ofwatercraft14. These waves extend for a wave length approximately equal to the length ofwatercraft14 in many instances. In some instances, the wave length is shorter or longer than the length ofwatercraft14.Lateral displacement system10 is configured for use withwatercraft14, which is a watercraft of any size, model, shape, or manufacture, including personal watercrafts. Additionally,lateral displacement system10 generates waves when attached to forward movingwatercraft14, wherewatercraft14 is moving through a fluid, the fluid generally being water. Attachment of at least one pair offoils12 occurs whenwatercraft14 is in the fluid in some instances and beforewatercraft14 is placed in the fluid in other cases.
• Referring toFIGS. 1-2, one embodiment of the present disclosure, including at least one pair offoils12, is displayed. In this embodiment,lateral displacement system10 includes at least one pair offoils12, with each foil having a base18 for attachment to watercraft14,base18 having afront surface20 and aback surface22. Foils also include anangled wing support24 connectingbase18 to acurved wing26 at awing angle28.Curved wing26 is positioned for the interaction with moving fluid. Features of the foils are described in further detail below. The foils oflateral displacement system10 are composed of carbon fiber, fiberglass, or any other suitable material such that a foil shape may be constructed and such that a foil may flex without permanent deformation or failure upon application of stress duringwatercraft14 movement. In some embodiments, foils are composed of a metal such as stainless steel to avoid corrosion and/or include additional materials, such as foams, to increase floatation of the foils. Components oflateral displacement system10 may be of unitary construction or may be an assembly of several components that are attached or joined to each other by attachment means, such as joints, slots, hinges, adhesives, or other suitable joining or fastening structures, features, or materials.
• An exemplary shape of the at least one set offoils12 is shown inFIG. 1A-B, wherecurved wings26 are concave, though foils may be of a different shape, such as those provided on m-selig.ae.illinois.edu/ads/coord_database.html. Foils of various shapes are contemplated for use in the present disclosure.FIG. 1A displays at least one set offoils12 from a front side, whileFIG. 1B displays at least one set offoils12 from a back side. The concave foil design creates an extreme pressure difference with an area of high pressure forming on the uppermost portion of at least one pair offoils12, and an extreme low pressure area on the underside of at least one pair offoils12 when at least one pair offoils12 is appropriately positioned onwatercraft14 and moving though fluid. The pressure difference creates lift in a downward direction through drag. The resulting downward force exerted on a hull ofwatercraft14 exceeds about 1,500 lbs in some instances, depending on watercraft speed and placement oflateral displacement system10.
• Details regarding components of at least one pair offoils12, shown inFIG. 1A-B, are herein discussed.Base18 functions as an attachment means for foils of the at least one pair offoils12 to be securely attached and released from positions onwatercraft14, as well as functioning as a support for the extension and orientation ofcurved wing26. To achieve these functions,base18 may be formed in various shapes, including a quadrilateral, a rounded quadrilateral, a circle, and oval, a higher order polygon, or other shapes suitable for support ofcurved wing26 and attachment of the foil to watercraft14. Thickness and size ofbase18 varies based on material and application, but generally are dimensions sufficiently large enough to accommodate the size and weight ofcurved wing26 andangled wing support24 at rest and while moving through a fluid.Base18 is likewise a sufficient size and thickness for secure attachment towatercraft14, and presents a surface area that is generally configured to be positioned adjacent to the hull ofwatercraft14 for attachment. In some embodiments,base18 is generally rigid and in other embodiments,base18 is an at least partially flexible base configured to conform to the hull ofwatercraft14. In some instances, flexibility is achieved through a living hinge machined or constructed intobase18. In other instances,base18 is composed of a flexible material, such as urethane rubber, neoprene-based rubber, natural gum rubber, or other such flexible materials. Additionally, flexible materials may be waterproof and UV protected materials. With such shapes, sizes, and material properties,base18 is configured to be conformed to the hull ofwatercraft14 for at least a portion ofback surface22, in both instances where the hull is relatively flat at the point of attachment and where the hull is contoured. Attachment means ofbase18 are discussed below in detail.
• As depicted inFIG. 2,front surface20 ofbase18 presents an attachment location forcurved wing26 viaangled wing support24. Connectingbase18 tocurved wing26 is angledwing support24, which holdscurved wing26 atwing angle28 relative tobase18 and relative to a plane normal tobase18 at the intersection ofcurved wing26 andbase18.Wing angle28 is approximately 30° in some instances, thoughwing angle18 is greater or less than 30° in other instances. Variation ofwing angle28 may change the characteristics of generated wake, where alarger wing angle28 generates larger waves than asmaller wing angle28 under similar conditions.Angled wing support24 is in a shape of a wedge as depicted in the example inFIGS. 1-2, though in embodiments not shown it may be another shape or structure capable of supporting and holding securecurved wing26 atwing angle28.Angled wing support24 is stationary with reference tobase18 andcurved wing26 in some embodiments, or adjustable relative tobase18,curved wing26, or bothbase18 andcurved wing26 in other embodiments. Adjustability is achieved through integration of features such as a gear, cog, a wedge and anchor, locking slots, or other means of adjustment sufficient for adjustingwing angle28 orcurved wing26 orientation.FIG. 3A-C depicts an embodiment wherecurved wing26 is adjusted by rotation ofangled wing support24 at its point of attachment tobase18.FIG. 3A shows an initial position, wherecurved wing26 is oriented such that it angles inward towardwatercraft14 in the direction ofbow44 ofwatercraft14. Rotation ofcurved wing26 andangled wing support24 occurs inFIG. 3B. The resulting position ofcurved wing26 inFIG. 3C shows the edge ofcurved wing26 that extends the greatest distance fromwatercraft14 is nearest awaterline34. In this embodiment, 360 degree rotation about an axis of rotation normal tobase18 at a point of attachment ofangled wing support24 tobase18 is possible, thus allowing the positioning ofcurved wing26 in various orientations. In embodiments not depicted,wing angle28 is adjusted by movement ofangled wing support24, and adjustment ofcurved wing26 orientation is provided using the same adjustment mechanism. It is contemplated that adjustment ofangled wing support24 proceeds either before attachment oflateral displacement system10 to watercraft14 or afterlateral displacement system10 is already attached towatercraft14.
• Referring back toFIGS. 1-2,curved wing26 provides surfaces for producing lift when in motion through fluid.Curved wing26 is concave in the direction of intended water pressure during movement ofwatercraft14, and convex in the direction opposite intended water pressure during movement ofwatercraft14, so that the thickness ofcurved wing26 is approximately even between its two faces with the larges surface area. In embodiments not shown, thicknesses vary and are not even in all locations between the two faces with the largest surface areas ofcurved wing26. Curvature is variable and in some instances is greater or less than the curvature depicted in the examples inFIGS. 1-2. The shape ofcurved wing26 may be square, rectangular, squoval, or any other shape suitable to provide downward lift atwing angle28. In some instances not depicted,curved wing26 is moved relative toangled wing support24 and/orbase18, such thatwing angle28 and/orcurved wing26 orientation is varied. In these instances, movement occurs at an attachment point or interface betweencurved wing26 andangled wing support24, where the means of adjustment include features such as a gear, cog, a wedge and anchor, locking slots, or other means of adjustment sufficient for adjustingwing angle28 orcurved wing26 orientation. It is contemplated that adjustment ofcurved wing26 proceeds either before attachment oflateral displacement system10 to watercraft14 or afterlateral displacement system10 is already attached towatercraft14.
• Referring toFIG. 4A-B, at least one pair offoils12 are used inlateral displacement system10, where a smaller,front foil30 is approximately 60% the size of a larger,rear foil32. Other proportions of sizes of front and rear foils30,32 are contemplated by the present disclosure, allowing thatfront foil30 is smaller thanrear foil32.Rear foil32 andfront foil30 are configured to be placed onwatercraft14 as a pair, though in embodiments not depicted, a single foil of a front or a rear size may be used.FIG. 4A shows the placement of at least one pair offoils12 from a front perspective view, whileFIG. 4B shows the placement from a rear perspective view. The dimensions and shape of one embodiment ofrear foil32 andfront foil30 of at least one pair offoils12 is shown inFIGS. 1-2. In one embodiment,curved wing26 ofrear foil32 has an exemplary length and width of 12 inches, though these dimensions may vary. For instance, these dimensions may scale according towatercraft14 size or according to the size and shape offront foil30 of at least one pair offoils12. Length and width ofcurved wing26 ofrear foil32 may be approximately equal or may have a length that is different from the width. In one instance,curved wing26 ofrear foil32 has a radius of curvature of about 27.7 and is approximately 0.972 inches thick. However, higher or lower radii of curvature and thicknesses are contemplated for the present disclosure. The radius of curvature may be constant, or may vary. Similarly, the thickness may vary or be constant.Wing angle28 ofrear foil32 is approximately 30°, though other angles are contemplated for use in the present disclosure. The ratio of lengths ofbase18 tocurved wing26 forrear foil32 and the ratio of widths ofbase18 tocurved wing26 forrear foil32 vary with application andwatercraft14. Upon attachment towatercraft14,curved wing26 ofrear foil32 is angled away fromwaterline34 and tilted upward at an approximate 10-15 degree angle ofattack50 relative to thereference waterline34. Other mounting angles relative towaterline34 are contemplated.
• The dimensions and shape of one embodiment offront foil30 of at least one pair offoils12 is additionally shown inFIGS. 1-2.Curved wing26 offront foil30 has an exemplary length and width of 8 inches, though these dimensions may vary. For instance, these dimensions may scale according towatercraft14 size or according to the size and shape ofrear foil32 of at least one pair offoils12. Length and width ofcurved wing26 offront foil30 may be approximately equal as depicted, or may have a length that is different from the width. In one instance,curved wing26 offront foil30 has a radius of curvature of about 13.1 and is approximately 0.895 inches thick. However, higher or lower radii of curvature and thicknesses are contemplated for the present disclosure. The radius of curvature may be constant, or may vary. Similarly, the thickness may vary or be constant.Wing angle28 offront foil30 is approximately 30°, though other angles are contemplated for use in the present disclosure. The ratio of lengths ofbase18 tocurved wing26 and the ratio of widths ofbase18 tocurved wing26 forfront foil30 vary with application andwatercraft14. Upon attachment towatercraft14,curved wing26 offront foil30 is angled away fromwaterline34 and tilted upward at an approximate 10-15 degree angle ofattack50 relative to thereference waterline34. Other mounting angles relative towaterline34 are contemplated.
• Adjustment of at least one pair offoils12 through either rotation ofangled wing support24,curved wing26, or bothangled wing support24 andcurved wing26, results in a generally wing-like orientation, similar to a wing of an airplane, when an edge ofcurved wing26 that is furthest frombase18 is positioned nearest to and oriented parallel to intendedwaterline34. This adjustable wing orientation is depicted inFIGS. 3A-C, and is useful in reducing the water weight that is required to produce a wave sufficient for the practice of watersport activities. In embodiments not depicted, the faces ofcurved wing26 with largest surface areas have contoured surfaces, so that whencurved wing26 is positioned in an adjustable wing orientation, contoured surfaces form a cambered adjustable wing, the operation and function of which are described below.
• Referring now toFIG. 5A-B, a foil or foils of at least one pair offoils12 include afin36 in certain embodiments, wherefin36 allows water to adhere to the surfaces ofcurved wing26 and facilitate a smooth aerodynamic transition of the fluid across the faces ofcurved wing26.Fin36 also serves to “track” in the water without creating cavitation across the faces ofcurved wing26 aswatercraft14 is in motion. Whilefin36 is shown with its largest face having a generally triangular shape inFIG. 5A, other shapes of this largest face are possible, including a quadrilateral, a rounded polygon, an oval, a circle and any other suitable fin shape for creating a smooth transition of fluid across faces ofcurved wing26. As shown inFIG. 6A,fin36 is positioned with its largest faces perpendicular to the largest faces ofcurved wing26 and parallel withwaterline34. In this position,fin36 is generally in line with the surface of water aswatercraft14 moves through the water. Attachment offin36 is achieved through features or materials such as adhesives, slots, or fasteners, or other suitable attachment means in some embodiments, while inother embodiments fin36 is of unitary construction withcurved wing26. The position offin36 with reference tocurved wing26 is shown inFIGS. 5B and 6B to approximately bisectcurved wing26, althoughfin36 may not extend as much or may extend less across the largest faces ofcurved wing26 in other instances. Similarly,fin36 does not approximately bisectcurved wing26 in some instances, but instead may unevenly divide the largest face ofcurved wing26 or may extend acrosscurved wing26 at an angle that is not approximately normal to the leading edge ofcurved wing26. In embodiments not depicted, the faces offin36 with largest surface areas have contoured surfaces, so thatfin36 forms a cambered winglet, the operation and function of which are described below.
• Now referring toFIG. 7,rear foil32 andfront foil30 of at least one pair offoils12 are attached to a hull ofwatercraft14 on afirst side38, wherefirst side38 is the non-surf side ofwatercraft14 due to placement oflateral displacement system10 on saidfirst side38. While positioning oflateral displacement system10 is shown onfirst side38, other locations such astransom40 or various locations on the hull are contemplated, such that the use oflateral displacement system10 whilewatercraft14 is in forward motion results in a “yaw” position and generation of waves. Similarly, attachment oflateral displacement system10 to the mid-ship or sides ofwatercraft14 is contemplated. To maximize yaw, one foil is placed forward of the center of gravity of the watercraft, while a second foil is located immediately forward of the transom. In instances where the “yaw” position is generated by pullingwatercraft14 towardfirst side38, waves are generated on the surf-side, or asecond side46 ofwatercraft14. When appropriately positioned,curved wing26 of at least one pair offoils12 is angled such that the largest, outward-facing surfaces ofcurved wing26face bow44 ofwatercraft14 and the surface whereangled wing support24 meetscurved wing26 faces stern42 ofwatercraft14. Thus,curved wing26 is angled to be generally tapered inward towardbow44 ofwatercraft14.
• The spacing between foils onwatercraft14 allowslateral displacement system10 to generate turbulent flow with an exponential effect and maintains a suitable pressure differential behind the foils. In many instances such as those depicted inFIG. 8,rear foil32 is positioned at a level of approximately waterline34 and generally about 18 to about 36 inches fromtransom40, stern42, or rear ofwatercraft14. Placement ofrear foil32 is variable based onwatercraft14 type, size, shape, and other factors, such that other locations ofrear foil32 onwatercraft14 are contemplated.Front foil30 is similarly depicted inFIG. 8 as offset fromrear foil32 nearer abow44 ofwatercraft14 at a level of aboutwaterline34. In other embodiments,front foil30 is closer or farther fromrear foil32 when attached towatercraft14. Generally,front foil30 is placed approximately 12 to approximately 18 inches towardbow44 from the center of gravity ofwatercraft14. An exemplary spacing betweenrear foil32 andfront foil30 is about 42 inches, though spacing varies based on several factors, including the location of the center of gravity for eachwatercraft14. For instance, alternative spacing is contemplated where foil orwatercraft14 sizes and shapes alter the ideal spacing between foils. Attachment betweenbase18 to the hull ofwatercraft14 is discussed below in detail.
• In order forlateral displacement system10 to be attached securely towatercraft14, a plurality ofattachment structures48 are utilized.FIG. 9 depictsattachment structures48 on foils oflateral displacement system10.Rear foil32 andfront foil30 are shown withback surface22 ofbase18 facing away fromcurved wing26. In instances wherebase18 is composed of a flexible material or include structures for flexibility,attachment structures48 are positioned to securely attach to the hull ofwatercraft14, even when the hull is contoured or otherwise uneven. In instances wherebase18 does not conform in its entirety to the hull, it is sufficient that atleast attachment structures48 are in contact with the hull. Back surface22 includesattachment structures48, which are shown to be suction cups in the depicted embodiment. However,other attachment structures48, such as straps, clamps, magnets, adhesives, slots, tabs, and clips, are compatible with the present disclosure. In one embodiment,attachment structures48 are any structure capable of reversibly attaching foils or wings oflateral displacement system10 to the hull ofwatercraft14.Attachment structures48, in this instance, are capable of being attached to and removed from the hull without damage tolateral displacement system10 orwatercraft14 and are capable of being located in multiple positions on the hull, as discussed above. In another embodiment,attachment structures48 are any structure capable of permanently attaching foils or wings oflateral displacement system10 to the hull ofwatercraft14. Attachment means oflateral displacement system10 may be built intowatercraft14 design in embodiments not depicted. Ropes, twine, or other support materials may be added tolateral displacement system10 to assist in attachment, removal, and/or storage oflateral displacement system10.
• Use of at least one pair offoils12 results in a lengthened wave, such that larger surfers are pushed by the wave and capable of surfing or interacting with the wave as desired.Front foil30 is approximately 60% of the size ofrear foil32 so thatfront foil30 is smaller and creates a cone of turbulence. The cone of turbulence matches the leading face of the largerrear foil32 when the foils are placed an appropriate distance from each other on the outside of the hull ofwatercraft14. This spacing leads to an exponential effect on the turbulent flow generated bylateral displacement system10.
• Referring toFIGS. 8 and 10, the effects oflateral displacement system10 on watercraft angle ofattack50 and lift are shown.FIG. 8 showswatercraft14 in an unpowered state, with little or no motion relative to the flow of the water it is floating in. At least one pair offoils12 is attached to the hull and spaced a distance from each other that depends on the watercraft and foil parameters, as discussed above. The spacing distance may be measured from similar surfaces of the foils. In the depicted example,rear foil32 is positioned approximately 18 to approximately 36 inches from stern42, onfirst side38 ofwatercraft14. In the same exemplary depiction,front foil30 is placed onfirst side38 ofwatercraft14 at a longitudinal distance of about 42 inches towardsbow44 ofwatercraft14 fromrear foil32. At least one pair offoils12 is positioned at a height of approximatelywaterline34, where at least a portion of the foils are beneathwaterline34. InFIG. 10,watercraft14 is powered and in motion. When forward motion is initiated, at least one pair offoils12 generates downward buoyant force on the hull ofwatercraft14. This buoyant force of pushes an equal amount of water weight in the opposite direction, (i.e. foilspush watercraft14 down) and the water is forced upwards, into a wave capable of being surfed. Whenwatercraft14 is pushed down, angle ofattack50 combined with a deadrise is approximately 30 degrees with respect towaterline34. Other combined angle ofattack50 and deadrise angles are possible and contemplated for use with the present disclosure. As shown inFIG. 10, the propeller may be pushed further belowwaterline34 whenwatercraft14 is in motion. In the exemplary depiction inFIG. 11, at least one pair offoils12 additionally induces a “yaw” position ofwatercraft14 to generate waves onsecond side46, as discussed in detail above.
• Referring toFIGS. 8 and 10,curved wing26 is shown whenwatercraft14 is at rest (FIG. 8) or in motion (FIG. 10). At rest, inFIG. 8,curved wing26 is at a 15degree angle50 relative to waterline34. However, whenwatercraft14 is powered and in motion inFIG. 10, a total angle ofattack50 of 30 degrees relative towaterline34 is shown.Curved wing26 generates downward lift whenwatercraft14 is in motion. The downward lift serves to pushwatercraft14 downward, and likewise pushes an equal amount of water upwards, producing a wave.
• Referring back toFIG. 7, downward buoyant force generated bylateral displacement system10 is not the only effect oflateral displacement system10, but also turbulence addition and distribution are determined. Foils oflateral displacement system10 add turbulence into the water stream, which serves to redirect turbulent water tofirst side38 ofwatercraft14. In general, the propeller ofwatercraft14 creates whitewash that trails behindwatercraft14. The whitewash is water infused with air. Because air is less buoyant than water, whitewash and turbulent water afford less floatation than water with less infused air.
• When nolateral displacement system10 is in place onwatercraft14, air bubbles introduced by cavitation created by the propeller exit the rear ofwatercraft14 equally between two waves. Entrapped air in the waves gives the waves less “push” to propel a surfer forward. In the case wherelateral displacement system10 is attached towatercraft14, a concentrated turbulent flow is added to the flow of water, such that the entrapped air exiting the propeller attaches to the much larger air bubble that is introduced to the flow. The resulting wave ends up having almost all of the entrapped air onfirst side38 ofwatercraft14. This leaves the other wake onsecond side46 clean with little to no entrapped air and results in more “push”, such that the surfer is capable of staying on top of the wave with greater ease.
• The present disclosure creates a large area of entrapped air that stays intact through the entire length of the wave until it exits the rear ofwatercraft14.Curved wing26 is designed to flex under the water whenwatercraft14 is in motion, resulting in the entrapped air bubble staying intact through the entire generated wave. Any break in the air bubble may result in turbulent flow and at least some reduction of wake quality on the “clean” side of the wave. Thus, material considerations for foils include the ability to flex and the avoidance of highly rigid materials that may result in decreased wake quality.
• Referring to an embodiment shown inFIGS. 12-14, the foils of at least one pair offoils12 are shaped as acambered wing52. In this embodiment,cambered wing52, an example of which is depicted inFIG. 12, is utilized to generate wake when attached towatercraft14.Cambered wing52 is attached to the hull ofwatercraft14 usingattachment structure48, which is a slot for a spoke or cylinder in the example inFIG. 13. However,attachment structure48 may be any structure capable of attachingcambered wing52 to an outside surface of the hull, such that wing extension and angle ofattack50 are adjustable.Cambered wing52 has an upper cambered surface and a lower cambered surface (FIG. 14A). The upper cambered surface presents a slower moving fluid flow overcambered wing52 than across the lower cambered surface, such that pressure is higher abovecambered wing52 and downward lift is generated whencambered wing52 is in motion onwatercraft14. Attachment structure48 (FIG. 14B) is located on a side adjacent to watercraft14, when attached. The shape ofcambered wing52 is depicted with an upper cambered surface and a lower cambered surface, though the curved path may differ in embodiments not depicted.Cambered wing52 may have any dimensions, such that it may be attached to an outside surface of the hull and generate downward lift upon forward motion ofwatercraft14.
• Cambered wing52 is attached towatercraft14 and extends perpendicularly fromwatercraft14 to eliminate or reduce the need for additional ballasts due to the lift it creates whenwatercraft14 is in motion. By utilizing a system that automatically controls how farcambered wing52 is extended, as well as angle ofattack50 ofcambered wing52, the amount of downward lift can be adjusted to a wide range of values based on application requirements. The downward lift will forcewatercraft14 deeper into the water, which causes the water to rise up in a direct relationship with the downward force applied bycambered wings52. This particular application forcambered wing52 extending fromfirst side38 ofwatercraft14 allows the operator to change the deadrise angle at both high speed and low speed. Changing how farcambered wing52 extends fromfirst side38 ofwatercraft14, as well as angle ofattack50 with reference towaterline34, allows an operator to regulate wave size and shape with a high degree of control.
• For example, afront wing56 could be angled at a 15 degree angle ofattack50, while running arear wing54 at a 3 degree angle ofattack50. This exemplary arrangement causeswatercraft14 to create a long, clean wave. In another instance,rear wing54 is adjusted to a 30 degree angle ofattack50 andfront wing56 has a three degree angle ofattack50. This exemplary arrangement may result in a short steep wave. When the ability to control how far eachcambered wing52 extends from the centerline or longitudinal axis ofwatercraft14, another layer of adjustability is possible. As discussed above, cambered wing structures are achievable through adjustment of a contoured embodiment ofcurved wing26 and through use of a contouredfin36, though these embodiments are not shown inFIG. 15A-B.
• Referring toFIG. 15A-B,lateral displacement system10 is depicted onwatercraft14 where the entire length ofwatercraft14 is visible (FIG. 15A) and in an enhanced view of the sites of attachment (FIG. 15B) of acambered wing52 embodiment of at least one pair offoils12. In this embodiment,lateral displacement system10 includes atfront wing56 andrear wing54. Eachcambered wing52 has at least oneattachment structure48, an upper cambered surface, and a lower cambered surface, where the at least oneattachment structure48 is configured to attach eachcambered wing52 to the hull ofwatercraft14.
• Use of both front andrear wings56,54 results in a lengthened wave, such that larger surfers are pushed by the wave and capable of surfing or interacting with the wave as desired.Front wing56 is approximately 60% of the size ofrear wing54 so thatfront wing56 is smaller and creates a cone of turbulence. The cone of turbulence matches the leading face of the largerrear wing54 when the wings are placed an appropriate distance from each other on the outside of the hull ofwatercraft14. This spacing leads to an exponential effect on the turbulent flow generated bylateral displacement system10. In some embodiments not shown,front wing56 is less than 60% the size ofrear wing54. In other embodiments not shown, atfront wing56 is larger than the size ofrear wing54. In some embodiments,front wing56 andrear wing54 are of substantially equal size and shape.
• At leastrear wing54 andfront wing56 are attached to the hull at an appropriate distance from each other. The distance may be measured from similar surfaces of the wings and is, in some embodiments, be approximately 42 inches, though variation of spacing depends onwatercraft14 and wing size, as discussed above.Rear wing54 is positioned approximately 18 to approximately 36 inches fromtransom40 ofwatercraft14.Front wing56 is placed onfirst side38 ofwatercraft14 at a longitudinal distance of about 42 inches towardsbow44 ofwatercraft14 fromrear wing54 in the depicted embodiment. As discussed above the spacing betweenfront wing56 andrear wing54 varies based on the center of gravity ofwatercraft14. Both front andrear wings56,54 are positioned at a height of approximatelywaterline34, where at least a portion of the wings are beneathwaterline34.
• Referring toFIG. 16, at leastcambered wings52 are controlled regarding the extension distance from sides ofwatercraft14 and regarding angle ofattack50. DC servo motors are compatible with the present disclosure to control the precise position ofcambered wings52 with regard to angle ofattack50 andwaterline34.Cambered wings52 are capable of being mechanically deployed and extended as required. Automation parameters ofcambered wing52 extension, angle ofattack50, deployment, and retraction are controlled by an operator inwatercraft14.
• For at least one pair offoils12 of any shape, sizes, or with attachments such asfin36 discussed herein, attachment to and extension fromwatercraft14 to generate waves includes embodiments where at least one pair offoils12 is built intowatercraft14. In these embodiments, at least one pair offoils12 extends from a location inwatercraft14 to the exterior of the hull, such that at least one pair offoils12 is rotatable fromwatercraft14 about an axis of rotation perpendicular to the longitudinal axis ofwatercraft14. Rotation of foils serves to alter angle ofattack50 and adjusts the waves generated onsecond side46. Extension distance from the hull is also controlled withinwatercraft14. Extension and angle ofattack50 alteration is performed manually by an operator inwatercraft14 in some instances, while in other instances this process is automated.
• The present disclosure contemplates methods of inducing lateral displacement by causingwatercraft14 to be placed in a “yaw” position bylateral displacement system10 placement, or placement of displacement features not depicted. For instance, in an embodiment not depicted, a rudder is placed on a bottom surface ofwatercraft14 forward the center of gravity ofwatercraft14. This rudder is a forward rudder and is smaller than the main, rear rudder ofwatercraft14. The forward rudder is configured to placewatercraft14 in a “yaw” position and thus generate waves as described above using fins or foils. The forward rudder is controlled from the helm of the boat, and control is automated in some instances or manually operated in other instances.
• As will be understood by those familiar with the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For instance,watercraft14 may additionally include offshore tankers, cargo ships, and sportfish boats. In another example,lateral displacement systems10 include shapes and structures not explicitly depicted, including fins and foils of various sizes and shapes and further including rudders. Attachment, mounting, or extension locations forlateral displacement system10 vary depending on structure used, watercraft size and shape, and activity desired to accomplish. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.

Claims (22)

1. A lateral displacement system for generating waves,

comprising:

a pair of foils including a front foil and a rear foil, each of the front foil and the rear foil having a base with a front surface and a back surface, a curved wing, and an angled wing support connecting the curved wing to the front surface of the base at a wing angle, wherein the base has at least one attachment structure on the back surface configured to attach the foil to a hull of a watercraft,

wherein the curved wing of the front foil extends out from its respective base a first distance and the curved wing of the rear foil extends out from its respective base a second distance that is greater than the first distance, and

wherein the pair of foils are coupled to a first side of the hull of the watercraft with the rear foil nearer a stern of the watercraft than the front foil with the pair of foils being configured for forcing the watercraft downward in a body of water when the watercraft moves forward in the body of water, causing rotation of the watercraft about a yaw axis toward the first side and generating waves sufficient for conducting watersport activities on a second side of the watercraft.

2. The lateral displacement system ofclaim 1, wherein the rear foil is positioned along the first side approximately 18 inches to approximately 36 inches from a transom of the watercraft.

3. (canceled)

4. The lateral displacement system ofclaim 1, wherein each base is flexible and is configured to place each of the at least one attachment structures in sufficient contact with the hull for attachment to the hull.

5. The lateral displacement system ofclaim 1, further including a fin mounted to the curved wing of the front foil with a largest fin surface oriented approximately perpendicular to a largest curved wing surface of the front foil, such that the largest fin surface is configured to be approximately parallel to the waterline when the front foil is attached to the watercraft.

6. The lateral displacement system ofclaim 5, wherein the largest fin surface is cambered.

7. The lateral displacement system ofclaim 1, wherein the curved wing of the front foil is configured for movement relative to its respective base.

8. The lateral displacement system ofclaim 7, wherein movement includes rotation of the curved wing of the front foil about an axis of rotation that is approximately perpendicular to its respective base.

9-15. (canceled)

16. A method of generating waves using lateral displacement of a watercraft, the method comprising the steps of:

providing a watercraft and a lateral displacement system, the system including a pair of foils;

extending the pair of foils from a hull on a first side of the watercraft, wherein a front foil of the pair of foils has a first length that extends a first distance out from the hull and a rear foil of the pair of foils has a second length that extends a second distance out from the hull, the second length being greater than the first length; and

moving the watercraft forward in water whereby interaction of the pair of foils with the water while the watercraft is moving forward (i) causes the watercraft to rotate about a yaw axis toward the first side, (ii) creates lift in a downward direction thereby forcing the watercraft downward, and (iii) generates waves sufficient for conducting watersport activities on a second side of the watercraft that exit at a rear end of the watercraft.

17. The method ofclaim 16, wherein the extending is accomplished by attaching the pair of foils to a surface of the hull of the watercraft using at least one attachment structure on the pair of foils.

18. The method ofclaim 17, further comprising the step of rotating each foil of the pair of foils about an axis of rotation that is approximately perpendicular to a longitudinal axis of the watercraft to alter an angle of attack relative to a waterline.

19. The method ofclaim 16, wherein the pair of foils is built into the watercraft.

20. The method ofclaim 19, further comprising the step of rotating each foil of the pair of foils about an axis of rotation that is approximately perpendicular to a longitudinal axis of the watercraft to alter an angle of attack relative to a waterline.

21. The method ofclaim 16, wherein the front foil creates a cone of turbulence in the water, the cone of turbulence having an outer edge that intersects with an outer edge of the rear foil.

22. The method ofclaim 16, wherein the front foil is located between a bow and a center of gravity of the watercraft.

23. A watercraft comprising:

a hull with a first side,

a stern,

a center of gravity,

a bow, and

a pair of foils including a rear foil projecting out from the first side and between the stern and the center of gravity and a front foil projecting out from the first side and between the bow and the center of gravity, the rear foil having a length sufficient for the rear foil to project a distance out from the first side that is greater than a distance the front foil projects out from the first side,

wherein, when the watercraft moves forward in water, the pair of foils are configured for causing the watercraft to rotate about a yaw axis and increasing displacement of the water by the watercraft.

24. The watercraft ofclaim 23, wherein the front foil has a bow-facing surface having a first surface area and the rear foil has a bow-facing surface having a second surface area that is greater than the first surface area.

25. The watercraft ofclaim 24, wherein first surface area is 64 square inches and the second surface area is 144 square inches.

26. The watercraft ofclaim 24 wherein the first surface area is approximately 44% of the second surface area.

27. A method of generating waves using the watercraft ofclaim 23 comprising moving the watercraft forward in the water whereby the front foil creates a cone of turbulence in the water having an outer edge that intersects with an outermost edge of the rear foil.

28. The method ofclaim 27, wherein moving the watercraft forward in the body of water whereby the watercraft is caused to rotate about a yaw axis toward the first side thereby generating a wave sufficient for conducting watersport activities on a second side of the watercraft.

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