The present disclosure relates generally to watercraft hulls and more specifically to a hybrid V-shaped hull with an inverted chine.
Planing hulls are ubiquitous in the marine industry. While the design and configuration of such hulls varies widely, many are designed to primarily utilize the effects of hydrodynamic lift generated by the hull's geometry at speed to support the vessel's weight. This allows planing hull vessels to “skim” atop the water “on plane”, permitting faster speeds when compared with similarly powered and sized displacement hull vessels. However, as navigable bodies of water are rarely absent of waves, it is advantageous for the running surfaces of a hull to meet the water surface at an angle (e.g., deadrise angle: angle between flat plane (water surface) and hull running surface). This induces a dampening effect that mitigates pitching and rapid vertical deceleration (commonly referred to as “slamming”) and generally provides a smoother, faster, and safer (more “seaworthy”) ride when compared to hulls with a predominantly flat bottom or low deadrise angles. Planing hulls with a distinctively angled, wedge-shaped running surface are commonly called “deep-vee” hulls, in reference to their “V” shaped transverse cross section.
The following is a non-exhaustive listing of some aspects of the present techniques. These and other aspects are described in the following disclosure.
Some aspects include a watercraft hull system, comprising: a hull having a fore end, an aft end, and a longitudinal axis extending between the fore end and the aft end; a V-shaped portion extending from the fore end toward the aft end along a portion of the longitudinal axis; and an M-shaped portion extending from the V-shaped portion toward the aft end, wherein the V-shaped portion gradually transitions to the M-shaped portion.
The above-mentioned aspects and other aspects of the present techniques will be better understood when the present application is read in view of the following figures in which like numbers indicate similar or identical elements:
While the present techniques are susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. The drawings may not be to scale. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the present techniques to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present techniques as defined by the appended claims.
To mitigate the problems described herein, the inventor had to both invent solutions and, in some cases just as importantly, recognize problems overlooked (or not yet foreseen) by others in the field of watercraft hulls. Indeed, the inventor wishes to emphasize the difficulty of recognizing those problems that are nascent and will become much more apparent in the future should trends in the industry continue as the inventor expects. Further, because multiple problems are addressed, it should be understood that some embodiments are problem-specific, and not all embodiments address every problem with traditional systems described herein or provide every benefit described herein. That said, improvements that solve various permutations of these problems are described below.
As discussed above, planing hulls of watercraft may include a wedge-shaped running surface or “V” shaped hull to provide a smoother ride when navigating through a fluid such as water. However, one drawback of this type of design can be a relative lack of stability when stationary or below planing speeds. Due to the nature of its “V” shaped cross section, when inclined/tilted to one side, the displacement, and thus buoyancy, on the side of the direction of inclination does not increase as quickly as comparable hulls with a flat bottom, “shallow-vee”, or multihulls (such as catamarans and trimarans). Therefore, the leverage opposing the inclination of the vessel, or “righting moment”, can be less than that of comparable hulls, resulting in decreased stability. This phenomenon can be particularly pronounced in smaller vessels, where the payload is a more significant percentage of the vessel's total weight, or in many cases, exceeds the empty weight of the vessel itself. In the case of passengers, the vessel's center of mass can be constantly moving or changing, and can create precarious scenarios such as when boarding or deboarding.
One way in which stability can be improved is by creating a watercraft with multiple hulls, such as a catamaran (two hulls) or trimaran (three hulls). However, this configuration also introduces new drawbacks. This includes a reduced amount of usable volume aboard the vessel, as the structure between the hulls (often referred to as the bridgedeck) must be of sufficient clearance above the water, which can be an especially challenging design complication for smaller vessels. Handling characteristics can also be significantly different from that of a traditional monohull.
A hybridized version of a deep-vee monohull and multihull emerged in the middle of the 20th Century in the form of a “cathedral hull” or “trihull”. These vessels typically have an “M” shaped transverse cross section and somewhat rectangular plan when viewed from above. While such designs are intended to improve the stability of “deep-vee” monohulls by utilizing the same principal as trimarans, as well as retain the practicality and internal volume of more traditional monohulls, they often fall short with regard to comfort and seaworthiness. The concave sections between the “vees” are often carried the entire length forward, resulting in a bow characterized by a somewhat “boxy” appearance with low (or negative) deadrise angles that “slam” the water surface when encountering large waves. Thus, in an effort to improve the static stability of the deep-vee hull, such designs have partially lost the original dynamic benefit of the deep-vee hull and its ability to dampen the impact of waves and provide a smoother, safer ride.
Embodiments of the present disclosure provide a watercraft hull intended to more completely realize the dynamic seaworthiness characteristics of deep-vee monohull designs and the stability benefits of cathedral/trihull designs, while minimizing the inherent disadvantages in both. As such, the watercraft hull of the present disclosure provides a deep-vee planing hull form which seamlessly transitions rearwardly from a “V” shaped cross section into an “M” shaped cross section.
The aft sections (˜60% of the length of the specific watercraft hull) are similar in form to a cathedral hull/trihull design, with concave regions of negative deadrise. The forward sections (˜40% of the specific boat's length as described in the present disclosure) are exclusively positive deadrise, similar in form to a traditional deep-vee hull design. This allows the forward section of the vessel to more efficiently “slice” the waves, while the rear section can provide more stability. The transition between positive deadrise and negative deadrise is seamless and without notable boundary. In specific embodiments, three chines on each side of the watercraft originate/terminate at the bow stem of the watercraft hull, not at the sheer (e.g., the longitudinal deck curve/line at the “top” of the watercraft hull), which differentiates the watercraft hull of the present disclosure from existing cathedral hull designs. Again, the watercraft hull of the present disclosure provides a transition between exclusively positive deadrise forward, to areas of negative deadrise aft, where the regions of negative deadrise are significantly less than 90 degrees. Some vessels, including some cathedral hulls, have regions of negative deadrise nearly perpendicular to the waterline. This can create undesirable and unsafe handling characteristics when turning.
Referring now to
In various embodiments, the watercraft hull 102 includes a transom 110. Conventionally, a transom may include a generally flat or planar, vertical section of the watercraft hull 102 that forms the rear, joining the sides and bottom of the watercraft hull 102, and frequently deck as well. On watercraft that are powered by one or multiple outboard motors 180, the transom 110 is where the outboard motor 180 would normally be affixed, and is reinforced for this purpose. While the transom usually spans the entire width of the vessel at its rearmost point, the embodiment of the present disclosure provides the transom 110 as only the middle of the three flat vertical aft sections, which include a vertical aft section 111a and a vertical aft section 111b, as the transom 110 is where any outboard motor may be affixed. The vertical aft sections 111a and 111b may be the furthest part of the stern 106 from the bow 104 and further from the bow 104 than the transom 110. In some embodiments, the vertical aft section 111a and 111b may be optional such that only the transom 110 exists.
In various embodiments, the watercraft hull 102 may include a sheerline 112 that forms a top edge of the watercraft hull 102, where the watercraft hull 102 would meet a deck. The watercraft hull 102 also includes a plurality of chines 114. A chine may include an abrupt change in cross-sectional angle in the watercraft hull 102. In the illustrated embodiment, the watercraft hull 102 includes a chine 114a, a chine 114b, and a chine 114c on the starboard side 108c (also referred to herein as starboard chines 114a, 114b, and 114c). The watercraft hull 102 includes a chine 114d, a chine 114e, and a chine 114f on the port side 108d (also referred to herein as port chines 114d, 114e, and 114f). The chine 114a corresponds with the chine 114f, the chine 114b corresponds with chine 114e, and the chine 114c corresponds with the chine 114d. When viewed in profile, a chine may be interpreted as a line and crease in a geometry of the watercraft hull 102. For example, in a common planing hull, there is one chine on either side of the planing hull, running fore-and-aft, where sides of the planing hull meet the bottom of the planing hull.
In various embodiments, the watercraft hull 102 may include a keel 116. The keel, in conventional watercraft, provides structure to the watercraft, extends longitudinally along the center (e.g., a longitudinal axis) of the bottom and may project from the bottom of the watercraft. The keel 116 that is included in the watercraft hull 102 of the present disclosure may not project from the bottom of the watercraft hull 102. Rather, the watercraft hull 102 may be a monocoque molded component of which the keel 116 is indistinguishable and merely forms a central “crease” along a centerline 117 of the watercraft hull 102. As such, because the keel 116 may be a “crease” along the centerline 117 of the watercraft hull 102, the keel 116 may be considered a chine as well. Furthermore, in some embodiments. a very shallow keel called a “skeg” could form the keel 116.
In various embodiments, the watercraft hull 102 may include a stem 118. Traditionally, a stem is the vertical timber or structural component at the bow of the watercraft. The stem 118 of the present disclosure may refer to the more vertical section of the centerline of the watercraft hull 102, which may be an extension of the keel 116 at the fore 108a of the watercraft hull 102. A forefoot 120 may reference a bend along the centerline of the watercraft hull 102 that forms the transition between the keel 116 and the stem 118.
To describe the shape, dimensions, and other physical attributes of the watercraft hull 102 several terms of art are used herein and referenced in
Deadrise may be an angle of a running surface relative to a line parallel to the waterline of the watercraft hull 102 (facing outward from the centerline of the watercraft hull 102). A deadrise angle of 0 degrees would be flat, parallel to the water surface; 90 degrees would be perpendicular to the water surface. A positive deadrise angle would indicate that the surface is angled outward away from the centerline. A negative deadrise angle would indicate the surface is angled inward toward the centerline. The deadrise of the watercraft hull 102 and chines 114a-114f are discussed in further detail below.
In some embodiments, the watercraft hull 102 may include a sponson 134a on the starboard side 108c and a sponson 134b on the port side 108d. The term sponson used herein may describe the minor hull portions making up the starboard side 108c and the port side 108d of the watercraft hull. Typical sponsons are projections form the side of a watercraft hull such as in a rigid inflatable boat (RIB). For example, sponsons may include inflatable tubes that are used to provide buoyancy and improved stability. Conventional sponsons are very pronounced and visibly distinct from the rest of the hull. The sponsons 134a and 134b of the present disclosure broadly describes the geometrically and materially seamless transition of these minor hull portions from a main portion 134c of the watercraft hull 102.
As discussed above, the watercraft hull 102 of the present disclosure provides a hybrid deep-vee planing hull form which seamlessly transitions rearwardly from a “V” shaped cross section into an “M” shaped cross section. As such, there is a seamless transition from a positive deadrise at the bow 104 of the watercraft hull 102 to a negative deadrise to the stern 106 of the watercraft hull 102.
An area 152b of the watercraft hull 102 defined by the chine 114b and the chine 114c (e.g., the area between chines 114b and 114c (also referred to herein as a second starboard side hull area)) and similarly an area 152e of the watercraft hull 102 defined by the chines 114d and the chines 114e (also referred to herein as a second port side hull area) may start with a positive deadrise at the bow 104 of the watercraft hull 102. This area that includes the area 152b and the area 152e may transition from having a positive deadrise to a negative deadrise at a distance from the bow 104 to the stern 106 of 20% of the LOA 122 up to 80% of the LOA 122. If the transition occurred forward of 20% of the LOA 122, the areas of negative deadrise and areas of relatively low deadrise just aft of the transition would be too far forward, resulting in an increased propensity to slam the water surface, particularly in rough sea conditions. Stated alternatively, areas of the forward sections of the watercraft hull 102 would not have the high deadrise angles needed and desired to effectively form a wedge shape and part the water with a dampening effect. Additionally, if the transition occurred aft of 80% of the LOA, the “sponsons” 134a and 134b would not be formed until much further aft, effectively lowering their volume and thus the wider distribution of buoyancy which affords the desired increased stability of the watercraft hull 102.
The portion of the area 152b of the watercraft hull 102 defined by the chine 114b and the chine 114c and the portion of the area 152e of the watercraft hull 102 defined by the chine 114d and the chine 114e having positive deadrise (e.g., the forward portion (forward of the crossover 140 and 142)) may have an angle range of greater than 0° to less than 90°. The angle may gradually decrease moving from the bow 104 to the stern 106 until the crossover 140 and 142 where the angle is 0 degrees. The deadrise then turns negative and gradually decreases until the deadrise is of a minimum angle of −10 to −60 degrees. This range allows for a compromise between static stability and dynamic handling characteristics. A negative angle less than 10 degrees (more parallel to water surface) would reduce the draft of the sponsons 134a and 134b, and thus their submerged volume and buoyancy, which could reduce the watercraft hull's overall stability. A negative angle greater than 60 degrees (more perpendicular to water surface) would result in less desirable (and potentially dangerous) handling characteristics. When turning the watercraft hull 102 at speed, negative deadrise angles within the range specified would permit the aft sections of the hull to “kick out”, “skim”, and “drift” atop the water during a turn. A negative angle greater than 60 degrees increases the likelihood of the aft sections of the watercraft hull 102 resisting the flow of water laterally across its geometry (“scooping” the water), reducing the maneuverability of the watercraft hull 102, and potentially causing the watercraft hull 102 to heel (lean) outward away from the direction of the turn, which can lead to a capsize.
At the maximum width of the hull or beam 124, the width of the area 152b of the watercraft hull 102 defined by the chines 114b and the chines 114c may range from 8%-25%. The beam 124 may be the point where the sponsons are fully formed. However, in other embodiments, the beam 124 may not be the point where the sponsons are fully formed. Similarly, the width of the area 152e of the watercraft hull 102 defined by the chines 114d and 114e may range from 8%-25%. Bound by areas of positive deadrise, the width of the area of negative deadrise on each side of the centerline should be in excess of 8% of the beam 124. Should this figure be less than 8% of the beam 124, either the buoyancy of the sponsons 134a or 134b may not be great enough to achieve the desired stability, or the angle of the negative deadrise may be too steep, or both.
In an embodiment, the portion of the area of the watercraft hull 102 defined by the chine 114a and the chine 114b (an area 152c that is also referred to herein as a third starboard side hull area) and the portion of the area of the watercraft hull 102 defined by the chine 114f and the chine 114e (an area 152f that is also referred to herein as a third port side hull area) may have a positive deadrise from bow 104 to stern 106. The deadrise may range from greater than 0° less than 90° along the LOA 122. The width of the area 152c of the watercraft hull 102 defined by the chines 114a and the chines 114b may range from 0%-25%. Similarly, the width of the area 152f of the watercraft hull 102 defined by the chines 114f and 114e may range from 0%-25%. The area of positive deadrise defined by chine 114a and chine 114b and the area of positive deadrise defined by chine 114f and chine 114e enhance maneuverability and handling characteristics by allowing the aft sections of the hull to lift and skim atop the water when turning on plane.
Thus, the watercraft hull of the present disclosure provides a transition from a “V” shaped hull with all positive deadrise to an “M” shaped hull with at least one area on both sides of the watercraft hull having a negative deadrise between two areas on both sides of the watercraft hull having positive deadrise. This may be accomplished by inverting a chine. As such, the watercraft hull of the present disclosures provides dynamic seaworthiness characteristics of deep-vee monohull designs and the stability benefits of cathedral/trihull designs, while minimizing the inherent disadvantages in both. As such, the watercraft hull of the present disclosure provides a deep-vee planing hull form which seamlessly transitions rearwardly from a “V” shaped cross section into an “M” shaped cross section.
The reader should appreciate that the present application describes several independently useful techniques. Rather than separating those techniques into multiple isolated patent applications, the applicant has grouped these techniques into a single document because their related subject matter lends itself to economies in the application process. But the distinct advantages and aspects of such techniques should not be conflated. In some cases, embodiments address all of the deficiencies noted herein, but it should be understood that the techniques are independently useful, and some embodiments address only a subset of such problems or offer other, unmentioned benefits that will be apparent to those of skill in the art reviewing the present disclosure. Due to costs constraints, some techniques disclosed herein may not be presently claimed and may be claimed in later filings, such as continuation applications or by amending the present claims. Similarly, due to space constraints, neither the Abstract nor the Summary of the Invention sections of the present document should be taken as containing a comprehensive listing of all such techniques or all aspects of such techniques.
It should be understood that the description and the drawings are not intended to limit the present techniques to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present techniques as defined by the appended claims. Further modifications and alternative embodiments of various aspects of the techniques will be apparent to those skilled in the art in view of this description. Accordingly, this description and the drawings are to be construed as illustrative only and are for the purpose of teaching those skilled in the art the general manner of carrying out the present techniques. It is to be understood that the forms of the present techniques shown and described herein are to be taken as examples of embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed or omitted, and certain features of the present techniques may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the present techniques. Changes may be made in the elements described herein without departing from the spirit and scope of the present techniques as described in the following claims. Headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description.
As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). The words “include”, “including”, and “includes” and the like mean including, but not limited to. As used throughout this application, the singular forms “a,” “an,” and “the” include plural referents unless the content explicitly indicates otherwise. Thus, for example, reference to “an element” or “a element” includes a combination of two or more elements, notwithstanding use of other terms and phrases for one or more elements, such as “one or more.” The term “or” is, unless indicated otherwise, non-exclusive, i.e., encompassing both “and” and “or.” Terms describing conditional relationships, e.g., “in response to X, Y,” “upon X, Y,”, “if X, Y,” “when X, Y,” and the like, encompass causal relationships in which the antecedent is a necessary causal condition, the antecedent is a sufficient causal condition, or the antecedent is a contributory causal condition of the consequent, e.g., “state X occurs upon condition Y obtaining” is generic to “X occurs solely upon Y” and “X occurs upon Y and Z.” Such conditional relationships are not limited to consequences that instantly follow the antecedent obtaining, as some consequences may be delayed, and in conditional statements, antecedents are connected to their consequents, e.g., the antecedent is relevant to the likelihood of the consequent occurring. Statements in which a plurality of attributes or functions are mapped to a plurality of objects (e.g., one or more processors performing steps A, B, C, and D) encompasses both all such attributes or functions being mapped to all such objects and subsets of the attributes or functions being mapped to subsets of the attributes or functions (e.g., both all processors each performing steps A-D, and a case in which processor 1 performs step A, processor 2 performs step B and part of step C, and processor 3 performs part of step C and step D), unless otherwise indicated. Similarly, reference to “a computer system” performing step A and “the computer system” performing step B can include the same computing device within the computer system performing both steps or different computing devices within the computer system performing steps A and B. Further, unless otherwise indicated, statements that one value or action is “based on” another condition or value encompass both instances in which the condition or value is the sole factor and instances in which the condition or value is one factor among a plurality of factors. Unless otherwise indicated, statements that “each” instance of some collection have some property should not be read to exclude cases where some otherwise identical or similar members of a larger collection do not have the property, i.e., each does not necessarily mean each and every. Limitations as to sequence of recited steps should not be read into the claims unless explicitly specified, e.g., with explicit language like “after performing X, performing Y,” in contrast to statements that might be improperly argued to imply sequence limitations, like “performing X on items, performing Y on the X'ed items,” used for purposes of making claims more readable rather than specifying sequence. Statements referring to “at least Z of A, B, and C,” and the like (e.g., “at least Z of A, B, or C”), refer to at least Z of the listed categories (A, B, and C) and do not require at least Z units in each category. Unless specifically stated otherwise, as apparent from the discussion, it is appreciated that throughout this specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining” or the like refer to actions or processes of a specific apparatus, such as a special purpose computer or a similar special purpose electronic processing/computing device. Features described with reference to geometric constructs, like “parallel,” “perpendicular/orthogonal,” “square”, “cylindrical,” and the like, should be construed as encompassing items that substantially embody the properties of the geometric construct, e.g., reference to “parallel” surfaces encompasses substantially parallel surfaces. The permitted range of deviation from Platonic ideals of these geometric constructs is to be determined with reference to ranges in the specification, and where such ranges are not stated, with reference to industry norms in the field of use, and where such ranges are not defined, with reference to industry norms in the field of manufacturing of the designated feature, and where such ranges are not defined, features substantially embodying a geometric construct should be construed to include those features within 15% of the defining attributes of that geometric construct. The terms “first”, “second”, “third,” “given” and so on, if used in the claims, are used to distinguish or otherwise identify, and not to show a sequential or numerical limitation. As is the case in ordinary usage in the field, data structures and formats described with reference to uses salient to a human need not be presented in a human-intelligible format to constitute the described data structure or format, e.g., text need not be rendered or even encoded in Unicode or ASCII to constitute text; images, maps, and data-visualizations need not be displayed or decoded to constitute images, maps, and data-visualizations, respectively; speech, music, and other audio need not be emitted through a speaker or decoded to constitute speech, music, or other audio, respectively. Computer implemented instructions, commands, and the like are not limited to executable code and can be implemented in the form of data that causes functionality to be invoked, e.g., in the form of arguments of a function or API call. To the extent bespoke noun phrases (and other coined terms) are used in the claims and lack a self-evident construction, the definition of such phrases may be recited in the claim itself, in which case, the use of such bespoke noun phrases should not be taken as invitation to impart additional limitations by looking to the specification or extrinsic evidence.
In this patent, to the extent any U.S. patents, U.S. patent applications, or other materials (e.g., articles) have been incorporated by reference, the text of such materials is only incorporated by reference to the extent that no conflict exists between such material and the statements and drawings set forth herein. In the event of such conflict, the text of the present document governs, and terms in this document should not be given a narrower reading in virtue of the way in which those terms are used in other materials incorporated by reference.
The present techniques will be better understood with reference to the following enumerated embodiments:
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Entry |
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