Bodyboard with planar, continuously variable stiffening element

[0001] The invention relates to bodyboards, and more particularly, to a bodyboard formed with a foam core and a generally planar stiffening plate positioned within the core to increase the rigidity of the bodyboard along any selected direction and in any selected portion of the bodyboard.

[0002] A bodyboard is used by a rider to maneuver on ocean waves. The rider typically holds one or both side rails of the bodyboard while the rider's hips, chest, knee, and/or foot are positioned on the top deck of the bodyboard. The combination of ocean surf, the rider's weight, and the rider's directing the bodyboard with the hands, elbows, torso, knee and/or foot places enormous flex and torsion stress on the bodyboard. The flex and torsion stress tend to distort the bodyboard, and generally this is an undesirable result because successful completion of maneuvers requires the bodyboard's responding adequately to the rider's steering. Force applied to the bodyboard that only distorts the board does not help the rider in redirecting the board. Thus, a high degree of stiffness of the bodyboard is desirable.

[0003] On the other hand, simply making the bodyboard to be very rigid is not a practicable solution because of weight concerns and because flex in the bodyboard may be desirable along certain sections of the board. For example, it may be desirable for the board to be more flexible at a transverse line about a quarter of the way aft of the nose and lead corners. Such flexibility allows the rider to pull up the nose, distorting it above the plane of the main deck of the bodyboard to keep the nose and lead corners from dropping under the water's surface in a dynamic situation where the nose is being forced downwardly. However, in the forward quarter of the board, it is generally considered desirable for the board to be very stiff along a transverse line so that the rider's steering inputs on one side of the board will effectively be transmitted to the opposite side of the board and redirect the opposite side. Notwithstanding these generalizations, variations in individual riders'styles and preferences for bodyboard performance characteristics, as well as wide variations in surf conditions, complicate the task of providing appropriate stiffening to a bodyboard.

[0004] Bodyboards are typically constructed of a buoyant foam core to which are attached an upper skin, a lower skin, and side rails. The added skins and rails provide durable outer surfaces, and the lower skin typically has a slick outer surface to speed the board on the water.

[0005] Other materials may be added to the board to stiffen it. For example, a layer of flexible plastic mesh may be laminated between the core and the bottom skin or between the core and the upper skin to make the board more rigid. As described in U.S. Pat. No. 5,114,370, the mesh may extend over only a portion of the board from the tail to a line about two-thirds to four-fifths of the way forward, leaving the portion of the board forward of the line unstiffened. This allows the nose of the board to be pulled up and distorted, as described above, but may leave the board insufficiently rigid in a transverse aspect for successful side-to-side steering maneuvers.

[0006] Another method of strengthening a body board is to insert one or more cylindrical rods, known as stringers, into holes drilled parallel to the longitudinal axis of the board from the tail end toward the nose end. As described in U.S. Pat. No. 6,036,560, the stringers may include a less rigid, polyethylene portion in the nose and a more rigid, resin-impregnated fiber material aft of the nose portion. Such stringer provide stiffness along a longitudinal direction in the aft portion of the board while allowing the nose to be flexible, as in the case of the mesh-reinforced board.

[0007] The invention is a structure and a method for providing flex in an engineered manner to a bodyboard, the engineered flex including increased stiffness along any selected direction and in any selected portion of the bodyboard. Typically, the structure is a generally planar stiffening plate disposed within the foam core of the board, the plate having an engineered shape designed to provide the selected stiffening while allowing, in other portions of the board, the nominal flexibility provided by the core, skins, and rails. The plate may alternatively be disposed elsewhere within the board, e.g., between a skin and the core, in the skin, or in a combination of locations as desired for providing the engineered flex. The structure may be installed in the board by laminating between layers of foam core and/or between the core and the skin. The structure may be built into a single layer of foam by expanding the foam core around the structure in a mold, by insertion of the structure into a cavity in the core or elsewhere in the board, or any other suitable means for securing the structure in the board.

[0008] FIG. 1 is a top plan view of the structure of the invention, showing the shaped stiffening plate, including perforations allowing integration of the plate with the core, in position in a bodyboard shown in dashed outline, the plate including a generally T-shaped outline with a transverse bar at the nose, a narrow, longitudinal neck extending aft of the bar, widening to a broad expanse at the tail end.

[0009] FIG. 2 is a top plan view of the invention as in FIG. 1, with a modified shape for the plate to provide a different flex configuration to the board.

[0010] FIG. 3 is an isometric view of the invention showing a stiffening plate being laminated between two portions of a foam core.

[0011] FIG. 4 is an isometric view of the invention showing a stiffening plate with an outline similar to that of FIG. 1 and including a crossed pattern of beams in the tail portion.

[0012] FIG. 5 shows two of the stiffening plates of FIG. 4 arranged in a generally parallel orientation with a vertical spatial separation between the plates.

[0013] FIG. 6 shows a stiffening plate similar to that of FIG. 4 with a drooped edge extending perpendicularly of the main body of the plate.

[0014] FIG. 7 is a side elevation of the invention showing the stiffening structure in the bodyboard, the structure disposed generally parallel to the upper and lower surfaces of the board.

[0015] FIG. 8 is a cross-sectional view of the invention cut from FIG. 2, showing the stiffening structure secured in the foam core of the bodyboard.

[0016] FIG. 9 is a cross-sectional view similar to FIG. 8 and showing the two stiffening plates arranged in the generally parallel, vertically spaced orientation similar to FIG. 5.

[0017] FIG. 10 is a cross-sectional view similar to FIG. 8, showing the droop-edged stiffening plate similar to FIG. 6.

[0018] As shown in FIG. 1, a bodyboard indicated generally at 10, built according to the present invention and configured to support a rider in water, has a generally elongate shape defining a longitudinal axis A, a nose end 12, two side rails 14, 16, and a tail end 18. An elongate foam core 20 (best seen in FIG. 8) provides the main bulk of board 10, and core 20 is typically surrounded by an upper skin 22 and a lower skin 24, as well as side rails 14, 16, all bonded to core 20. However, the invention encompasses all types of construction for a bodyboard, with or without the skins and rails.

[0019] Core 20 is preferably formed of expanded polypropylene foam, although the invention can be used with any core used for a bodyboard, including without limitation any of the following materials, alone or in combination: expanded or extruded polystyrene foam, expanded or extruded polyethylene foam, expanded polyethylene/styrene foam alloy, known as Arcel foam, any alloyed expanded foam, extruded polypropylene foam, any alloyed extruded foam, any crosslinked foam, or any bun stock foam.

[0020] Referring again to FIG. 1, the invention includes an element 26 coupled to the bodyboard, preferably to the core. Element 26 preferably includes a substantially solid and rigid, generally planar plate. Element 26 is configured to provide to the bodyboard a resistance to flexing in response to the rider's applying a bending force to the bodyboard. Element 26 is preferably formed of either molded carbon fiber or a sheet of carbon fiber. Element 26 can be formed of any material that can provide a resistance to flexing, including, without limitation, G-10 fiberglass, in molded or sheet form, thermal plastic formed by molding or extruding and with or without fiber-reinforcing, cast thermal plastic resin, and/or cast thermal set resin.

[0021] Element 26 preferably has a shape, when viewed from above or below, of a broadening-based T. That is, it includes a first beam, such as bar 28, that is oriented transverse longitudinal axis A of board 10, and preferably is generally perpendicular to longitudinal axis A. First beam 28 provides resistance to flexing in a nose portion, indicated generally at 30, of board A in a direction preferably generally perpendicular to longitudinal axis A. Thus, first beam 28 provides a resistance to a bending force along a first vector extending between one corner 32 of nose portion 30 and an opposite corner 34.

[0022] The base of the T of element 26 is formed by a second beam, such as bar 36, that extends aft of bar 28 in a direction along, preferably generally parallel to, and preferably generally coincident with or encompassing longitudinal axis A. Thus, second beam 36 provides resistance to a bending force along a second vector that is not parallel to the first vector, and preferably is generally perpendicular to the first vector. Element 26 can be provided with any shape and any set of any number of beams in any orientation selected to provide a particular set of stiffening characteristics. Element 26 is preferably a unitarily-formed structure, but may include separate beams, or separately-formed beams coupled together.

[0023] Bar 36 has a length defined between a first end adjacent nose portion 30 and a second end adjacent tail 18 and, as bar 36 extends aft, it preferably increases in width, beginning at mid-fore portion 38 and continuing to the broadened base of the T of aft portion 40. The wider the bar, the greater the resistance to bending and thus the resistance to the bending force applied along the vector parallel to longitudinal axis A increases in a continuously varying amount over a portion of the foam core. In addition, the board gains increased resistance to bending forces applied in the rear portion transverse or oblique to longitudinal axis A.

[0024] Aft portion 40 of element 26 preferably extends from adjacent each side rail 14 to adjacent the opposite side rail and provides a generally broad expanse. Aft portion 40 thus provides resistance to a bending force applied in any direction. It can be seen that element 26 is configured to provide resistance to flexing in response to a plurality of bending forces applied to core 20 along a plurality of vectors.

[0025] Element 26, as best seen in FIGS. 7-10, is coupled to the core by virtue of its being embedded therein, and this can be accomplished in several ways that will be described below. Element 26 preferably includes one or more holes 42, preferably a spread pattern of holes, extending through the plate portion of element 26. Holes 42 serve to secure element 26 in a fixed position in core 20 because the foam above element 26 and the foam below element 26 preferably extend through the holes and are bonded together, thus effectively bolting element 26 in place. Holes 42 may be circular or have any other suitable shape. For example, as best seen in FIGS. 4-6, holes 42 are formed around additional beams 44, 46 that are oblique to longitudinal axis A and provide resistance to a bending force along a vector oblique to longitudinal axis A. However, element 26 may function in the board without the holes. Element 26 may be held in place by adhesive, or by the adhesive properties of the foam core or other layers adjacent element 26.

[0026] An embodiment of the invention includes first and second generally planar elements 26 as shown in FIG. 5. The two elements 26 are preferably coupled to core 20 by embedding therein and have substantially the same shape and are aligned one above the other, and are spaced apart from one another in a generally parallel configuration. The pair of elements provide additional rigidity to the board, and it is believed to increase resistance to the bending force in more than an additive manner because it distributes the bending-force resistance vertically in the core. The elements alternatively may embody substantially different shapes with common aspects or completely independent shapes as desired to provide a selected stiffening profile to the board.

[0027] As best seen in FIGS. 8-10, core 20 defines an upper surface 48, and element 26 is oriented generally parallel to the upper surface of the core. In an embodiment shown in FIGS. 6 and 10, element 26 includes a planar portion 50 and an edge portion 52 that is oriented generally perpendicular to planar portion 50 and to upper surface 48 of core 20. Edge portion 52 provides an added degree of resistance against bending forces that would distort element 26 out of the plane generally defined by planar portion 50 because edge portion 50 provides a beam with added thickness relative to such bending forces.

[0028] A preferred method for assembling the bodyboard with the stiffening plate is depicted in FIG. 3, where a first layer of foam 20a and a second layer of foam 20b are shown being laminated together and to plate 26 disposed therebetween. The layers are formed from any conventional method, either separately or as a single layer that is then sliced into two. In either case, layers 20a, 20b may then be laminated together by conventional means. The material for element 26 may be selected in coordination with the material of the foam core to provide bonding between the core and element 26 in response to thermal pressure treatment of the layers while plate 26 is in place. Additionally or alternatively, plate 26 may be bonded to layers 20a, 20b by adhesives. As noted above, the holes 42 allow bonding between layers 20a, 20b within the area of plate 26, effectively to bolt plate 26 into place and to discourage relative lateral movement between element 26 and core layers 20a, 20b.

[0029] Alternatively, the bodyboard may be assembled by suspending element 26 centrally in a bodyboard mold, e.g., by vertically disposed pins detachably hung from an upper side of the mold and detachably affixed to element 26. Then foam may be blow into, and expanded in the mold, surrounding element 26 and fixing it in place in the foam core. After the foam core is removed from the mold, the pins are pulled out of element 26 and the foam core. Alternatively, the pins may be fixed to mold, and removing the foam core from the mold will remove the pins from the foam core and element 26. Removal of the pins from the core may leave tunnels in the foam core which may be closed by subsequent thermal pressure treatment and/or by filling with a suitable material.

[0030] Other methods of assembly of the bodyboard including placing element 26 between the foam core and the top or the bottom skin. Alternatively, element 26 may be embedded in the top or bottom skin, for example by laminating element 26 between two layers of skin, and then laminating the skin to the foam core. However, both of these two methods can be expected to provide somewhat different stiffening characteristics from embedding element 26 in the core.

[0031] Another method for constructing the bodyboard is to provide a conventional body board with a slit or opening, e.g., from the rear, to an envelope-like space within the board. The space may be provided by either forming the board with an open envelope therein, or by cutting an envelope-like space into a bodyboard. With such an opening and space, element 26 may be inserted through the slit and fixed in place by sealing the opening. Element 26 may be further fixed in place by coating it with adhesive before insertion, and/or thermal pressure treatment of the board with element 26 in place, or by other suitable means. With such a structure, the bodyboard may be produced and then one of a variety of shaped elements 26 may be later selected and installed in the bodyboard.

[0032] It is believed that the disclosure set forth above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed herein. Similarly, where the claims recite a or a first element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.

[0033] It is believed that the following claims particularly point out certain combinations and subcombinations that are directed to one of the disclosed inventions and are novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower or equal in scope to the original claims, are also regarded as included within the subject matter of the inventions of the present disclosure.