Waveform reinforced skateboard deck

A waveform reinforced skateboard deck with an intermediate body extending between a nose end and an opposing tail end, the deck further including an outermost top rider bearing surface and an outermost bottom truck mounting surface with at least a portion of at least one of the surfaces having a plurality of spaced apart elongated waveforms defining peaks and troughs projecting along a substantially sinuous path between the nose and tail ends.

BACKGROUND

1. Field of the Disclosure

The disclosure relates broadly to riding platform constructions, and more specifically, to improvements in skateboard deck construction.

The variety of tricks and stunts that may be performed using a skateboard continues to evolve as more and more skateboarders continue to push the envelope. This push places additional demands on the skateboard deck to withstand the repeated punishment associated with such tricks and stunts. Speed, vibration, impact, bending, compression, tension, sliding, spinning, grating, grinding, and torsion related forces may all be encountered during a particular trick or set of tricks. As one example, riding rails, curb edges, or other similar structures places considerable stress on the deck. Riders continue demand more deck durability as they seek to expand the envelope of what may be done with a skateboard. While rigidity and durability remain significant concerns, cost and performance are paramount as well. Trading these features off against one another makes skateboard deck design a challenging effort.

A variety of deck designs to improve strength, durability, and performance have emerged over the years. A well-known conventional approach is to use a laminated deck with several layers of wood plies with bonding agent sandwiched between adjacent layers. Bonding agents with different strengths have also been employed. However, such approaches have been known to significantly increase the overall weight of the deck. The addition of such weight often detracts from the performance characteristics of the deck and other solutions have been sought.

Another approach may be found in U.S. Pat. No. 6,460,868 (expired) and its related continuation-in-part U.S. Pat. No. 6,782,929, both to Madrid. In these patents, layers of the deck are embossed with a set of corrugations running parallel to one another and parallel to the linear direction of the grain in an upper and lower ply of the assembled deck. While such construction purports to strengthen the deck in terms of rigidity and torsion, it is apparent that projecting the corrugations with pointed ridges running parallel to the linear grain may introduce additional stress or fracture lines in the same direction as the parallel grain. Such construction has been found to frequently split along the grain line as straight corrugations lack torsional rigidity.

Given the drawbacks of the prior approaches to increasing the deck strength of a skateboard without sacrificing performance, there exists a need for an improved skateboard deck construction better able to withstand the demands of today's skateboarders by increasing the torsional rigidity of the deck.

BRIEF SUMMARY

In accordance with at least one embodiment disclosed herein, a skateboard deck is provided with an intermediate body extending between a nose end and an opposing tail end with at least a portion of at least one of the outermost surfaces of the deck having a plurality of spaced apart elongated waveforms defining peaks and troughs projecting along a substantially sinuous path.

In another implementation, the deck is comprised of multiple layers with at least one layer having a uni-directional grain pattern and the waveforms of at least one layer snake back and forth across the uni-directional grain pattern.

In another implementation, the waveforms are defined by compound curves.

In yet another implementation, the waveforms include curved and straight line segments.

In another implementation, the peaks and trough of the waveforms of adjacent layers are aligned or substantially aligned.

In another implementation, the peaks and trough of the waveforms of adjacent layers are offset from one another.

In yet another implementation, the waveforms cross back and forth across both a longitudinal grain and a transverse grain.

A method of constructing a waveform reinforced skateboard deck is also disclosed herein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In general terms, a number of exemplary waveform reinforced skateboard decks and methods of reinforcing skateboard decks are disclosed herein. Such waveform reinforced skateboard decks and methods of constructing the same seek to overcome the drawbacks of imparting a set of corrugations running in the same direction as the grain in at least one ply of a skateboard deck. In at least one exemplary embodiment, the reinforced skateboard deck may incorporate elongated snaking waveforms that may be imparted into at least one of its plies or layers and generally extend between at least a portion of the first and second ends of the skateboard deck. The snaking waveforms made up of peaks and troughs generally cross back and forth across, through, over and/or under at least one uni-directional grain in the same or another layer to strengthen the deck. The elongated waveforms may be imparted into a ply during a pressure forming process in a method of reinforcing and strengthening the skateboard decks. Alternatively, a form or insert incorporating the waveforms may be inserted between adjacent layers. Descriptions of several exemplary embodiments follow.

Referring now toFIGS.1-7, a skateboard deck (or deck), generally designated20, constructed to receive a set of front and rear trucks21with wheels23to form a complete skateboard assembly25as shown inFIG.7, is illustrated. In this first exemplary embodiment, the deck20generally includes a main or intermediate body22interposed between a nose end24and a tail end26. It will be appreciated that the terms nose and tail generally relate to the direction of travel with the nose end typically pointing in the direction of travel. However, as skateboards may be ridden in either direction, the terms nose and tail are generally interchangeable for purposes of this description and merely used as convenient terms to indicate a direction of travel.

With continued reference toFIGS.1-7, the deck20further includes an upper foot bearing or riding surface28and an opposing underside or undersurface30providing a mounting region for a set of opposing front and rear trucks with each truck21(FIG.7) bearing a set of wheels23(FIG.7). Both surfaces have an exposed outermost deck surface but may be made of a single ply or contain multiple plies. In this description, it will be appreciated that one of ordinary skill in the skateboard construction and assembly arts would understand how to select and mount the trucks and wheels to the deck20described herein to assemble a complete skateboard25(FIG.14) for riding.

As best shown in the right side view ofFIG.5, the profile of the foot bearing surface28is planar or substantially planar in the main body22(intermediate or middle region), although a slight central hump or rise may be present. The front end of the middle region then transitions in a gentle curve toward the lower surface30and then curves back upwardly away from the lower surface30and outwardly to the nose end24. Such curvature generally defines the transition34between the main body22and the nose end24of the deck20. The nose end24of the deck20terminates in a curved leading edge27. Similarly, the rear end of the main body22transitions in a gentle curve toward the lower surface30and then curves back upwardly away from the lower surface30and outwardly to the tail end26. This curvature generally defines the transition36between the main body22and the tail end26of the deck20. The tail end of the deck terminates in a curved trailing edge29. In this exemplary embodiment, when viewed from the side as inFIG.5, the deck20somewhat resembles a recurve bow with a relatively flattened central section. However, in some decks, the intermediate, nose, and tail sections may all be substantially planar with no transition curvature between adjacent sections. It will be appreciated that the entire foot bearing surface28encompasses the upper surface of the main body22, nose end24, and tail end26as most riders will use the entire upper surface of the deck20when riding using a variety of foot positions.

As best shown inFIGS.1-5, the deck20includes a left side38and an opposing right side40, both of which are generally straight edges that transition into the curved regions27,29forming the outer perimeter of the nose end24and the tail end26, respectively. It will be appreciated that the sides of the deck may be bowed outwardly or inwardly or take other shapes other than a linear straight edge.

A particular length of the deck20is generally defined between longitudinally opposing points of the curved leading edge27and curved trailing edge29of the deck20with the maximum length along a longitudinal line projecting between the opposing outermost extensions of the nose end24and tail end26. The length of the deck defines the reference for the longitudinal (or lengthwise) direction of the ply or layer grain. On the other hand, the deck width of the main body22is defined by the distance between the opposing straight edges38,40of the left side and opposing right side and defines the reference for the cross (transverse) direction of the ply or layer grain as further explained below. Both the longitudinal and transverse grains are uni-directional along the length or width, respectively, of the deck.

With reference toFIGS.1-6, it will be appreciated that the deck20is constructed of a number of wooden plies or layers as best shown inFIG.6. In this exemplary embodiment, seven plies42a-c,44a-b, and46a-bare used in constructing the deck20. However, it will be appreciated that the number of plies is not meant to be limiting and either a single ply or multi-ply deck may be used. As shown in the cross-section view ofFIG.6, there are three center plies42a-cwherein the centermost ply42bis represented as being oriented with a lengthwise grain running generally in the direction of nose end24to tail end26of the deck20or short end to short end. The adjacent center plies42a,42csandwich the centermost ply42band are represented as being oriented with a transverse or cross grain direction with the grain generally running from long side38to long side40of the deck20. Each of the centermost plies42a-cspans the entire width and length of the deck20. The cross grain is generally parallel to one another and perpendicular to the length of the deck. Such combination of lengthwise and cross-wise grain between plies strengthens the skateboard deck by providing a variety of wood grains at right angles to one another. However, the sole use of plies with a uni-directional linear grain direction still introduces likely areas of weakness parallel to the grain direction or on or adjacent to a specific grain line as the deck20is bent, flexed, compressed, torqued, or otherwise contorted in use. Exemplary common stress points are directly on or adjacent the grain lines such as shown at62a-finFIG.3falling into either lengthwise grain lines56or cross-grain lines58. Stress along these points often results in the fracturing, splitting or other failure of board integrity. The embodiments disclosed herein go at least one step further to further strengthen the deck20as will be discussed below.

With reference toFIGS.3and6, the two upper plies44a-b(FIG.6) also span the width and length of the deck20. However, at least a portion of both upper plies44a-bincludes a plurality of elongated waveforms, generally designated50a-c(exemplary selections inFIG.6for ease of description). In this exemplary embodiment, each waveform includes a non-linear peak52and adjacent non-linear troughs54a,54b(example waveform with peak and adjacent troughs shown inFIG.3) to either side unless too close to the edge of the deck to accommodate all three components of the waveform. The troughs are generally one-half the distance between adjacent peaks but this is not meant to be limiting. The peaks represent the outermost extent of the waveform while the bottom of each trough represents the innermost extent of each waveform. Together, the peaks and troughs follow the general meandering direction of the associated waveform50a-csuch that the peaks and troughs meander or snake back and forth across both at least uni-directional lengthwise grain56and/or uni-directional cross-grain58of the deck20when viewed from above (FIG.3, for example). The lengthwise and cross-grain lines56,58represent the grain direction in the corresponding center plies50a-cor as may be found in the outer plies44a-bor46a-bas well. The intermediate upper waveform ply44bincludes similar waveforms, generally designated60a-cinFIG.6with similar peaks and troughs. In this exemplary embodiment, the waveforms50a-cof the uppermost ply44aand the waveforms60a-cof the upper intermediate ply44bare substantially in vertical alignment with the adjacent peaks of adjacent plies being substantially vertically aligned and the adjacent troughs of adjacent plies also being substantially vertically aligned as shown inFIG.6, although the waveforms may also be offset from one another from ply to ply.

More specifically, with continued reference toFIGS.3and6, the waveform50a-cin the exemplary uppermost ply42ameander back and forth across both the lengthwise grain lines56and cross-grain lines58such that the waveforms50a-ccrosses the lengthwise grain or cross-grain at stress points62a-fat other than parallel or right angles. Instead, the waveform crosses back and forth across the uni-directional lengthwise grain or cross-grain of at least one other ply in the deck20at an obtuse or acute angle relative to the lengthwise or cross-grain directions at a plurality of locations. For example, the peak of waveform50apasses through stress points62b,62c, and62eat obtuse or acute angles while peak50bpasses through stress point62dand peak50cpasses through stress point62a. Each waveform50a-cincludes at least one trough that also passes through the long grain56or cross grain58at various stress points at other than parallel or right angles. It will be appreciated that adjacent waveforms may share a common trough portion.

Referring toFIG.6, the upper intermediate ply44bincludes similarly aligned waveforms60a-cand is located adjacent the topmost center ply42a. The introduction of waveforms50a-cand60a-cinto the uppermost plies44a-b, respectively, over the top surface70of the center ply stack42a-cfurther reinforces the deck20at likely linear grain induced stress points (for example, at long grain or cross grain points62a-f) where high concentrations of stress are most likely to result in deck fatigue and failure thus lowering the likelihood of a structural deck failure. Such meandering waveforms overcome the linear grain weak points and further supplement the incorporation of lengthwise grain and cross-grain orientations in different plies of the deck20. In other words, the curving waveforms reduce the likelihood of the deck splitting along a linear grain orientation due to increasing the torsional rigidity of the deck20as such points of weakness and throughout the deck.

In a like manner, the lowermost plies46a-bare constructed the same as the uppermost plies44a-bbut inverted relative to the uppermost plies44a-band applied together adjacent the bottom surface72(FIG.6) of center ply stack42a-cthereby further reinforcing the underside30of the deck20. Lowermost plies46a-binclude peaks61a,61b, as for example inFIG.4, and adjacent troughs similar to their upper ply counterparts in this exemplary embodiment. It will also be appreciated that the waveforms may appear in or be imparted into the same ply having a uni-directional grain, either longitudinal or cross-grain, or in adjacent ply. In addition, the waveform plies may be provided in the form of an insert between adjacent plies.

The advantages of the wave pattern (e.g. plurality of waveforms50a-c,60a-c) over a straight corrugation format as in earlier approaches is that the two outermost layers of skateboard deck plies, layers, or veneers typically have a longitudinal grain, and as such, are stressed by a similarly directional linear embossed corrugated pattern. The wave pattern of the embodiments disclosed herein serves to dissipate and disrupt potential stress cracks through not continuously following the outer layers of wood veneer grain direction. If a crack should appear, the wave pattern may also serve to reduce the crack from spreading further. The relative importance of snaking back and forth across longitudinal (single direction plywood grain) is to reduce longitudinal splitting parallel to the grain (mixture of with grain and cross-grain in same layer using a snaking reinforcement element). The same applies to snaking back and forth across cross-grain plies as well.

In this exemplary deck embodiment illustrated atFIGS.1-7, the waveform pattern includes a set of individual waveforms that are generally in the form of a sine wave, parallel or substantially parallel to one another, and equidistantly spaced throughout the deck both longitudinally and transversely. As shown inFIG.3, taking the waveform generally designated73, as an exemplary representation of an individual waveform, each individual waveform has its own wavelength (lambda 1) such as defined by the gap or spacing between adjacent peaks (or crests)75a,75bon the same waveform73. The amplitude for an individual waveform is defined as one-half the distance between a peak75afor example and an adjacent trough77on the same waveform or one-half the wave-height (peak to trough). In this exemplary embodiment the wavelengths and amplitudes of each individual waveform are constant or substantially constant throughout the deck, although this is not meant to be limiting as explained for other embodiments below.

In addition, in this exemplary embodiment of the waveform reinforced skateboard deck20, the waveforms have a constant or substantially constant wavelength (lambda 2) defined for example as the spacing64between adjacent peaks65a,65bof adjacent waveforms67,69inFIGS.3and6. The waveforms also have a second amplitude when viewed in cross-section as shown inFIG.6. As shown inFIG.6, the amplitude is one-half of a vertically aligned distance (also referred to as the wave height or depth) indicated as the short segment66between the horizontally projecting line85and the trough83adjacent to peak81. This amplitude may be held constant or relatively constant throughout the deck. However, variations to waveform orientations, spacing, locations, continuity, and to wavelengths and amplitudes in either top, bottom, side, or cross-sectional viewpoints at different positions throughout the deck are also contemplated and fall within the scope of this disclosure with some non-limiting examples of such variations described below.

The equidistantly spaced parallel waveform sinewave curvature described above is not meant to be limiting. One example of an alternative waveform pattern that may be incorporated into the deck200is shown in the top view ofFIG.8. In contrast to the embodiment described above forFIGS.1-7, the deck200inFIG.8incorporates a set of waveforms250a-cwith peaks252a-cspaced further apart than their counterparts inFIG.3. InFIG.8, the spacing between peaks on adjacent waveforms has been increased approximately 1.5-2.0 times the spacing of the spacing of the deck20inFIG.3. The deck200is also shorter in length but wider in width to demonstrate the applicability of the waveforms to different sized decks. Thus, it will be appreciated that the wavelengths and spacing between adjacent peaks and troughs may be varied from deck to deck and also within the same deck as discussed below.

In another exemplary embodiment as illustrated in the cutaway view ofFIG.9, a portion of a deck300with an alternative waveform is shown. While a smooth, curving, continuous waveform is preferred, the exemplary waveforms350a-cmix both curved segments351aand linear segments351bthat are continuous throughout the waveform. In this exemplary embodiment, the peaks of each waveform have a gradual curved transition such as that exemplified by peak353. Thus, while prior embodiments disclosed herein incorporate waveforms presenting a compound curve of continuously curving segments, other variations may incorporate linear segments or even pointed peak or troughs provided such segments cross the long grain356and cross grain358at acute or obtuse angles. In addition, it will be appreciated that the waveforms may be continuous throughout the deck or discontinuous. Discontinuous waveforms may be used on the lower surface30of the deck20creating a gap where the trucks21are mounted, on the upper or lower surface where a logo is imprinted, or where stress points are not found to be as critical for deck durability for example. In addition, waveforms with gaps may be used to allow for localizing stress reduction. It will further be appreciated that adjacent waveforms may have peaks and troughs that are offset from one another and/or inverted at different locations relative to the opposing segments of the adjacent waveform. Non-adjacent waveforms may have such construction as well. While a purely sawtooth waveform consisting of linear segments with sharp peaks and troughs is not preferred, embodiments constructed with such waveforms meandering back and forth across the long grain and cross grain orientations of the deck would fall within the scope of this disclosure.

In yet another embodiment of the skateboard deck, generally designated400, the wave forms may be tilted or skewed relative to the longitudinal grain456and cross grain458directions as best shown inFIG.10. Here, the five waveforms450a-eillustrated are all skewed relative to the length of the deck400but still cross back and forth over the lengthwise grain456and cross-grain458of the same ply or at least one other ply. InFIG.10, the skew angle is approximately 135 degrees measured from the left side edge438. However, this skew angle is not meant to be limiting. Other waveform variations may be found in deck400as well. For example, waveform450fis a single arc and not a compound curve. Waveform450gincludes a short straight segment451aand a curved segment451bwith a sharp peak457at the transition. The waveforms between waveform450gand450hgradually lose their sharp peaks until becoming completely smooth in waveform450h. The majority of the waveforms are constructed with compound curves as in waveform450h. At the top end427of the deck400, a dual linear segment (or with slight curvature)450icreates a wider spacing455abetween the edge427of the deck400and the waveform450ithan the spacing455bbetween waveform450iand waveform450j. Such variation of spacing is not limited to the edge of the deck400and may be incorporated at any point in deck400between waveforms and the waveforms of other decks20,200,300described herein as well.

Materials: Conventional wood plies may be used in constructing the skateboard deck with adhesive between layers. The waveforms may be imparted or embossed onto the plies during the manufacturing process or added as lightweight, durable inserts constructed of a suitable material. Trucks and wheels have a conventional construction.

Method of manufacturing: Conventional deck construction techniques may be used with some modifications. Prior to final lamination and shaping of the deck, one or more inserts bearing a selected waveform are introduced above and/or below selected layers, veneers, or plies of the deck. The plies are then compressed to impart or emboss the waveforms into the plies using conventional press techniques. The waveform plies are then added to the top and/or bottom of the center plies having the long grain and cross grain with adhesive between each adjacent layer. The entire deck is then pressed and shaped (bent) into the desired final shape. The deck is held in the preferred shape until the adhesive is cured to retain the deck in the desired shape generally resulting in an exemplary arrangement such as that shown inFIGS.1-7.

In view of the foregoing, at least one object supported by one or more embodiments described herein is to introduce a waveform with peaks and troughs into one or more plies (or as inserts between plies) of a skateboard deck wherein the waveform crosses back and forth over, under, or through a uni-directional grain in the same or other ply to reinforce the deck. One exemplary skateboard deck may comprise a plurality of plies or layers with at least one layer including grain running in a substantially linear direction and at least one reinforcement layer including a meandering waveform with a combination of peaks and troughs that cross over or under the grain of the same or at least one layer instead of parallel to that grain.

At least one other layer projecting at substantially right angles to the grain of the at least one layer may be introduced wherein the meandering waveform crosses the grain of the at least one other layer as well. The waveform may take a variety of shaped including a sinewave, compound curved, sawtooth or combination thereof and may project across the entire deck or a portion thereof. In another embodiment, the waveform is continuous while in another the waveform may be discontinuous. One exemplary deck includes a set of seven plies with three central plies including a central long grain ply sandwiched by two cross grain plies, which in turn are covered by a set of two waveform plies may provide the construction of at least one deck embodiment.

It is also an object of at least one embodiment disclosed herein to improve prior strengthening process and skateboard deck constructions. By providing a plurality of waveforms in one or more deck layers that meander or snake back and forth a uni-directional grain in an adjacent layer, areas of stress concentration are better distributed about the deck thus increasing rigidity in more than one direction to enable improved performance of various skateboard techniques and maneuvers.

These and other objects may be satisfied by one or more embodiments disclosed herein, as well as many of the intended advantages thereof, will become more readily apparent when reference is made to the entire description taken in conjunction with the accompanying figures with the understanding that the embodiments described herein may satisfy one or more of the objectives.

It will be appreciated that the number, location, shape, spacing, continuity, wavelength, and amplitude of the waveforms may vary from the deck to deck as well as between plies or inserts or within the same ply or insert of a deck. Individuals waveform may also have such variations as well such as varying the shape, continuity, wavelength, or amplitudes along the length or width of the deck. It will be appreciated that a variety of waveforms may be incorporated into a skateboard deck constructed in accordance with this disclosure. Features and combination of features may be mixed as well. The variety may include waveforms spanning the length and width of the deck, even parallel spacing, offset waveforms, inverted waveforms, unevenly spaced waveforms, waveforms curved throughout, waveforms with linear segments crossing the longitudinal and cross grains, waveforms with discontinuous segments, waveforms spanning less than the length or width of the deck, and/or waveforms with a mixture of linear and curved segments.

In one exemplary implementation, an improved skateboard deck having a generally planar main body configuration extending into a nose end and an opposing tail end with a first elongated side edge and an opposing second elongated side edge between the nose and tail ends, a top rider bearing surface, and a bottom truck mounting surface. At least one of the top and bottom surfaces has a plurality of spaced apart elongated waveforms defining peaks and troughs projecting along a sinuous path between the nose and tail ends with the waveforms snaking back and forth across a uni-directional grain pattern of an adjacent deck layer.

It will be appreciated that the curved waveform corrugations (troughs and peaks) create strengthening not only in a lengthwise direction but also in a widthwise direction of the deck. The size of the radii of the waveforms may also be varied to allow tuning of the added strength bias (length vs. width) to be adjusted locally or throughout the deck where the waveforms are present.

It is also contemplated to incorporate an additional layer (plastic or otherwise) applied to the outer ply on the bottom side of the skateboard which will also become corrugated in the manufacturing process to serve as a low friction layer and with differing graphic decoration possibilities as compared to wood.

In addition, top layer and bottom layer veneers may be provided with the embossed or imprinted wave patterns and orientated in opposing directions to equalize stresses in the overall laminate and avoid warpage.