Cleat

Abstract

A cleated sole for footwear such as an athletic shoe designed for field sports, trail running or rugged walking. A midsole layer includes shock attenuating structures. The outsole includes a plurality of crossbeams formed as curved ground facing portions oriented from the medial to the lateral border of the sole. Cleats are mounted on the lower facing surface of the crossbeams. The outsole to midsole interface above each crossbeam is commensurate in shape to the lower facing curved surface of the crossbeam. Pressure created by a cleat striking the ground surface during use is diffused through the crossbeam, outsole and midsole into the wearer's foot. This moderates the cleat pressure pattern while providing side to side stiffness for the sole.

Description

CROSS-REFERENCE TO PRIOR APPLICATION

[0001] This application claims the benefit under 35 USC §119(e) of U.S. provisional application serial No. 60/309,053 filed Jul. 26, 2001.

SUMMARY OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to a sole for an article of footwear, and more particularly to cleated sole structures for shoes that include a midsole, an outsole, and ground engaging cleats depending from the outsole.

[0004] 2. Description of the Related Art

[0005] It has long been known to provide shoes with soles that include protrusions from the ground facing surface to aid traction. If many small protrusions or a large surface area of protrusion tops make ground contact, the pressure of weight bearing is fairly evenly distributed and gives a uniform sense of pushing back against the bottom of a wearer's foot. To enhance traction in circumstances such as use on muddy footpaths, very uneven walking surfaces, or while participating in sports such as baseball, soccer, field hockey, hurling, lacrosse, Australian rules, cricket, golf, rugby, or American Football, footwear may be provided with more substantial and discrete gripping elements protruding lower from the outsole. The direction “lower” is the orientation towards the supporting surface below the shoe during use when the wearer is standing. In this patent application, specified shapes of major traction elements are termed cleats.

[0006] It is generally preferred to avoid the use of cleats on most shoe soles since they penetrate surfaces more deeply than do flatter soles and thus cause more erosion or floor damage. The lower contact area associated with cleats also increases the rate of wear of the sole. It has thus up to now been accepted that cleats are not a good idea for use on casual or dress footwear or for footwear that might be used on surfaces vulnerable to unwanted wearing away.

[0007] The portions of a shoe generally below the upper are collectively termed the sole and it is well known in the art to subdivide the sole into layers. As a device to disperse the point pressure, sometimes called “cleat pressure”, arising from the provision of gripping elements on the ground engaging surface of an outsole, it is known to include a midsole.

[0008] A further well known portion of a sole is the most lower layer which is referred to by shoe designers as the “outsole.” The outsole layer has traditionally been adapted for ground engagement by selecting abrasion resistant materials, and by attaching gripping elements by processes such as molding, use of screw threads, by nailing, or by cementing. Substantial gripping elements depending lower from an outsole, and as herein define as “cleats”, provide tractional advantages to a wearer but are also known to make more likely discomfort to the foot by adding weight to a shoe, or by causing such problems as local sole distortion during load bearing, “hot spots”, point loading, higher pressure zones, or “cleat pressure” points. By way of an example, Hockerson in U.S. Pat. No. 6,145,221, issued to coinventor of the invention of this disclosure, describes the problem of shoes for use in football, soccer and rugby that are provided with truncated conical cleats. When such a cleated athletic shoe is weighted, as when the wearer runs over the playing field, the cleats push upwardly against the outsole. The outsole reacts by deforming and pressing upwardly against the bottom of the user's foot. This undesirably creates a condition known as “point loading” on the user's foot at the cleat locations. Over a period of repeated use, this point loading can result in foot discomfort and fatigue. The long term exposure to “point loading” or any of the other cleat related complaints, may result in injuries such as plantar fasciatis, metatarsal problems, stress fractures, bone spurs, tenonitis, “stone bruises”, or blisters.

[0009] In an effort to meet this long felt want of reducing the discomfort resulting from the provision of cleats on an outsole, it has been common to add a layer known as a “midsole” in or through the space separating the upper's lower surface and the outsole's upper facing surface. The direction “upper” is the orientation towards the wearer of the shoe during use when the wearer is standing. This added layer has been taught in many forms, the art mentioned earlier includes some examples. While the addition of a midsole may somewhat alter the cleat to foot force transfer pattern, the added layer also adds weight to what is often already a heavy shoe due to the dense and voluminous material required for the cleats. Furthermore, the increased total thickness of the combined outsole, midsole and cleats tends to elevate a wearer's foot away from the ground during use and thus increase the risk of injuries. As the distance from the ground to the sole of a wearer's foot is increased by a sole, the side to side or lateral stability of the foot and ankle is reduced. This makes an acute injury, especially an injury to the ankle such as a sprain or break in the tibia or fibula, more likely.

[0010] Midsole structures can also be a factor in injury. Risk of ankle injuries has been demonstrated to be 4.3 times more likely if air cells are included as a midsole design feature. (British Medical Journal article, spring 2001). A further problem with the added midsole thickness is a decrease in flexibility of the sole, an undesirable side effect in that it reduces the natural foot bending at the ball of the foot of a wearer.

[0011] Another response to the concerns of weight, cleat pressure and sole thickness in relation to injury has been to reduce the length of the cleats. This will reduce weight and the elevation of the wearer's foot but removes some of the traction benefits of the cleat.

[0012] Another area of development in footwear has been the provision of curved lower directed segments of the sole unit. While provision of curved outsole, midsole or combined sole segments has been taught as a way to modify foot biomechanics during ground interaction, the effect has been directed to changing the gait of a wearer.

OBJECTS OF THE INVENTION

[0013] It is an object of this invention to provide for placement of cleated elements on an outsole while dissipating concentrated pressure on the sole of the wearer's foot that arises from the use of the cleated footwear, most especially on a firm or hard surface.

[0014] Another object of the invention is provide a cleated sole which reduces the problems of point loading, cleat pressure, or related effects that arise from a wearer's use of a cleated shoe. A further object is to provide a lightweight and cushioned cleated sole.

[0015] Other objects and advantages are provision of a cushioned midsole without adding excess weight, spreading cleat pressure without inhibiting sole flexion, and balancing the need for traction and cushion in a sole without adding excess thickness.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIGS. 1A and 1B are partially cut away side elevational views of an article of prior art footwear and an article of footwear made in accordance with the present invention;

[0017] FIG. 2 is a side view of a simplified prior art shoe;

[0018] FIGS. 3A and 3B are plan views of the prior art sole of FIG. 2., with FIG. 3B showing a sectional view taken along the line 3B-3B of FIG. 3A;

[0019] FIG. 4 is a bottom view of an embodiment of a sole of the present invention;

[0020] FIG. 5 is a side view of the sole of FIG. 4., with the upper partially removed;

[0021] FIGS. 6A and 6B are bottom plan views of an embodiment of a sole of the present invention, with FIG. 6B showing a sectional view taken along the line 6B-6B of FIG. 6A;

[0022] FIGS. 7A to 7E are bottom plan views of embodiments of soles incorporating the present invention;

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The invention in general provides a sole structure for attachment to an upper to form an article of footwear. The term “sole” includes all those elements of an article of footwear which are attached below the upper. These may typically include such items as a midsole (which may be wrapped onto the side wall of the upper), an outsole, shock attenuating components and stabilizing components. The lasting board, sometimes termed an “insole”, occurs above the sole and is considered a part of the upper. The term “upper” is used to include those pieces and components of a shoe that cover the foot above the sole. In the context of this invention it includes any structure adapted for engaging the foot or an existing shoe in such a fashion as to hold the disclosed sole on the foot of a wearer. An upper may include such things as a lace closed bag of material, a series of straps or a bag of elastic fabric.

[0024] The sole has an upper surface on which the wearer's foot rests during use of the sole. The wearer's foot may be placed directly on the sole or may be separated by layers of material such as a lasting board, sockliner or other components. The wearer's foot may also be displaced above the upper surface of the sole by an existing shoe, as would be the case when the sole is attached as an overshoe. The sole may have side walls that extend above the plane of the upper surface, as would be the case when a foam midsole forms a wrap onto an upper or a cupsole is provided.

[0025] The sole has an outsole layer which features a lower surface which is adapted for ground contact by the inclusion of a plurality of “cleats”. The “outsole” is the most lower layer of sole material. A “cleat” , since the term is applied vaguely in the world of footwear designers, is herein used to describe an element of a shoe that is attached to the lower facing surface of a shoe sole and having an extent of at least 5 mm measured generally perpendicular to the surrounding sole surface and measured in a lower direction. Furthermore, a “cleat” of this patent application and invention is distinguished from cosmetic attachments, general gripping or tread patterns or sole textures in that the height of the cleat measured from the most lower surface of the local outsole to the maximum generally perpendicular extent of the element shall exceed the width of the element in at least one direction measured along the plane of the ground at the tip of the element where it would contact the ground during normal use. Such a measurement of width would be about perpendicular to the vertical axis of the element in question and would be in a plane about parallel to the plane of the local lower facing surface of the outsole where the cleat is attached.

[0026] The sole further includes a midsole between the upper and the outsole. The term “midsole” is used to describe any shock attenuating structure such as foam, air cells, springs (internal or external), or other devices mounted between the upper and the outsole wherein the term “between” is used to express a position of being placed in a space separating the surfaces of the outsole and the upper. The midsole material is softer than the outsole material by at least 10 points on the Shore A hardness scale to permit perceptible differentiation by a consumer, at least in the areas where the midsole is adjacent to the outsole in the crossbeams.

[0027] The sole is invisibly divided into regions according to the overlying parts of a wearer's foot during use. These regions are the heel, the midfoot, the forefoot and the toe area. The sole lower surface has a rear edge and a front edge. The sole lower surface has a medial edge and a lateral edge which meet in the middle of the rear edge and the middle of the front edge. The length of a sole is the distance between the front and rear edges of the lower sole surface measured linearly along the longitudinal axis.

[0028] The heel region is generally below a wearer's calcaneous and is approximately the rear 20-30% of the sole length. The midfoot is the region forward of the heel but behind the region corresponding to the ball of the foot which is referred to as the forefoot. The midfoot extends about from 20-30% to 55-60% of the sole length measured from the rear edge of the sole upper surface. The forefoot is about 55-60% to 85-90% of the length of the sole from the rear edge of the sole upper surface.

[0029] The toe region includes the sole area below the phalanges of a wearer and any additional sole material forward of this region. It extends from 85 to 100% of the sole length from the rear edge of the sole. The variation in the position of regions is due to individual differences in the proportions of foot parts of wearers. Naming invisible regions does not indicate a need for the sole to extend through these areas. The sole has a longitudinal axis defined by a line generally connecting the mid points of the heel and forefoot regions of the sole or connecting their extrapolated positions if these regions are not physically present. The horizontal width of the sole is measured at about 90° to the longitudinal axis and parallel to the ground. The vertical thickness is measured at about 90° to the longitudinal axis and about 90° to the ground.

[0030] The sole has a thickness between the upper and lower surfaces along the longitudinal axis. This thickness varies along the length of the sole from the front edge to the rear edge. This variation in thickness is observed when the cleats are removed and only the base layer of material in the outsole is considered along with the midsole. Since the cleat lengths may vary, the total sole thickness may appear constant, ignoring the inter-cleat spaces when the cleat lengths are included or, as is traditional, the sole thickness may taper from the rear edge to the front edge at a non linear rate, and thus offer such features as toe spring.

[0031] The lower surface of the sole is radiused across the local width of the outsole and midsole from medial to lateral to form at least two crossbeams. “Radiusing” is taken to mean the providing of a round or elliptical curvature to the surface about an axis across the width of the sole. This radiusing produces a sole region which is thinner on either side of the crossbeam as measured in section but is generally of even vertical thickness along the length of the crossbeam. At least one cleat depends from each of at least two radiused sections which are termed herein as “crossbeams.” That is to say, there must be a plurality of crossbeams and each must have at least one cleat, not that one cleat extends to both crossbeams, although two cleats may both extend to two crossbeams and thus meet this structural description. The crossbeams must be at least 12 mm wide in some part of their side to side sole span in a shoe built on a last of net length 290 mm, measured along the longitudinal axis, to provide an adequate pressure dispersion. This minimum width of the radiused section is reduced or enlarged in direct proportion to the length of the last bottom used to construct a sole.

[0032] The base layer of the outsole has both a lower and a upper surface which remain largely parallel where the outsole forms a part of the crossbeam, discounting any thickening, texturing or tread elements. The lower surface of the midsole material is radiused to fit against the upper surface of the outsole base layer of material in the crossbeams.

[0033] The outsole may be made of a great number of different solid materials known in the art, including hard rubber. It is, however, preferred that a hard solid plastic is used to form the base layer of the outsole. This same material may be used to form the cleats but these can also be made of a different material. The best materials for an outsole of the present invention would be selected from the solid plastics; TPU, PU, Delryn, Surlyn, Hytrel, Pebax, Nylon, and such others as are known in the art or may be added to the field later. The upper may be made of any material and may be structured in any of the many known forms in the footwear industry.

[0034] It was not previously known that a curved form applied fully across a midsole in combination with a cleat bearing outsole is a useful method of dissipating cleat to foot forces without adding excess weight, instability or thickness to the shoe sole. It was previously believed that appending gripping cleats to curved sole sections would cause a clawing effect; a tearing of the cleat element through or along the surface of the ground as the shoe rolled forward during the heel to toe motion of walking or running and that this turf or surface resisted action would have a significant energy cost.

[0035] Tests on cleated soles that were made to model the embodiments herein described have found the energy cost of cleat motion on or through the surface to be relatively imperceptible while the advantages of the cleat pressure dissipation and stability with low weight afforded by this invention are discernible by a wearer. Thus the unique combination of a midsole, an outsole, cleats and the specific placement of the cleats on curved crossbeams, sections or segments of the combined midsole and outsole has been surprisingly found to alter the comfort of the cleat pressures on the sole of a wearer's foot while effectively maintaining the grip length of a cleat without adding the extra weight and instability of added thickness as would occur to a midsole in which the same extra thickness was added to its entirety.

[0036] While the instant invention of this specification works when the outsole is made of rubber, of special note is that the structure of the invention has been found particularly effective in cleat pressure redistribution in outsoles of hard plastic, by which is meant the solid plastics TPU, PU, Delryn, Surlyn, Hytrel, Pebax, Nylon, and such others as are known in the art or may be added to the field later. The reason is that these materials are relatively incompressible, a property that makes them a good choice for cleated soles since it promotes cleat penetration of a surface. These same materials were previously associated with the discomfort of increased cleat pressure for a wearer. This additional advantage of the special structure of the sole of this invention is seen when an outsole of hard plastic is equipped with a cleat of the same or a different material, such as steel, aluminum alloy, ceramic or a solid plastic. The solid hard plastic outsole material works better than rubber for an outsole of this invention because it is less prone to sheering of the cleat than is a rubber outsole.

[0037] The provision of the specific form of a curved outsole with midsole combination into sections referred to herein as “crossbeams” is effective with a single crossbeam but greater benefit is produced when more than one cleat bearing crossbeam is provided on the sole of a shoe, as detailed for this invention. This is due to the tendency of a single crossbeam on a sole to form a pivotal cross axis or medial-lateral fulcrum on the sole which a plurality of crossbeams on a sole will reduce or remove. Further, the structure of the sole of this invention has a most effective embodiment when the outsole is provided with one or more openings or “windows”. The provision of a foramen allows a greater number of degrees of freedom for the outsole to distort as ground contacting pressure is conducted between the cleat and a wearer's foot through the soles relatively incompressible but flexible material and the compressible midsole. It is important that the provision of crossbeams to bear cleats is extended across the sole from medial to lateral to avoid opposing flexibility by running from proximal to distal.

[0038] FIG. 1A shows a wearer's foot 2 within the heel of a cut away upper 4 of a prior art shoe and resting on a lasting board 6 that is attached to the top surface of a midsole 8. On the lower surface of midsole 8 is attached an outsole 10 with two cleats 14 depending from the outsole 10 lower surface. Cleats 14 are in contact with ground 12 and the force 16 resulting from load bearing of the wearer's foot 2 bearing down on the lasting board 6 is shown schematically by arrows. A portion of force 16 passes through outsole 10 and midsole 8 to act on wearer's foot 2 on the upper surface of the lasting board 6 as force 18 shown schematically by arrows. The force 16 is little diverged in its passage to force 18 and tends to cause wearer's foot 2 to suffer local discomfort or hot spots 20 and 22.

[0039] FIG. 1B, shows a wearer's foot 2 within the heel of a cut away upper 4 of a shoe of the present invention and resting on a lasting board 6 that is attached to the top surface of a modified midsole 24. On the lower surface of midsole 24 is attached a modified outsole 26 with two modified cleats 28 depending from the outsole 26 lower surface. Cleats 28 are in contact with ground 12 and the force 30 resulting from load bearing of the wearer's foot 2 bearing down on the lasting board 6 is shown schematically by arrows. Force 30 passes through outsole 26 and midsole 24 to act on wearer's foot 2 on the upper surface of the lasting board 6 as force 34 shown schematically by arrows. The force 30 is dispersed in its passage 32 shown schematically by arrows to force 34 and is thus less likely to cause wearer's foot 2 to suffer local discomfort or hot spots (none shown).

[0040] The upper 74 may be of any form desired. Broadly the upper is any mechanism suitable for holding the sole of this invention in position on the foot of a wearer during use. The upper may be secured to the top surface of the midsole 24 by cement and by the inclusion of a lasting board 6 in a California slip last construction. Many other suitable methods and constructions can be used for the forming of an upper and its attachment to the sole of this invention. For example, string lasting, flat cement lasting, moccasin construction or welting may be employed.

[0041] FIG. 2 shows a simplified typical prior art shoe 36 with an upper 38 attached to the upper surface a midsole 40. An outsole 42 is attached to the lower surface 44 of midsole 40 and has cleats 46 depending from the lower surface 48 of outsole 42. FIG. 3A shows the lower surface 48 of outsole 42 of FIG. 2. with cleats 46. The cleat is shown in partial section along B-B in FIG. 3B. The midsole 40 and outsole 42 have cleat 46 attached to the lower surface 48 of outsole 42. Cleat 46 is nominated as a cleat by virtue of extending at least 5 mm in the lower direction measured generally perpendicular to the surrounding sole surface 50, and the height of the cleat 46 measured from the surrounding sole surface 50 to the maximum generally perpendicular extent of the element 52 exceeds the width 54 of the cleat in at least one direction measured along the plane of the ground at the tip of the cleat 56 where it would contact the ground during normal use. In this example of an element defined as a “cleat” for the purposes of this patent, cleat 46 has its height at a maximum along the vertical edge from arrow C to arrow CC and the width 54 is at a minimum at the tip of the cleat 56 at the top of the section 60 of cleat 46.

[0042] FIGS. 4 and 5 show the lower surface of outsole 66 in one embodiment of the invention. The outsole has a front edge 70 and a rear edge 72, and it may be made of materials as previously described. The lower surface of the outsole has a medial edge 74 and a lateral edge 76 which meet in the middle of the rear edge 72 and the middle of the front edge 70. The outsole's base layer 94 has both a lower surface of outsole 66 and a upper surface of outsole 78 which remain largely parallel where the outsole 68 forms a part of a crossbeam 80. Imaginary lines 82 show the position of the crossbeam which is formed by the curving lower portion of midsole 84 and outsole 68. Depending down from outsole 68 on the crossbeam 80 are rear heel cleats 86, 88. Midsole 84 material outcurve 90 fills the crossbeam 80 and contacts the upper surface of outsole 78. Partially cut away upper 92 is shown for relative position only and no special structure of upper 92 is claimed as a part of this invention.

[0043] Outsole 68 and midsole 84 are concavely curved across their width from medial edge 74 to lateral edge 76 to form crossbeam 80 and crossbeams 96, 98,100. If outsole 68 and midsole 84 had only a single crossbeam selected from the crossbeam 80 and crossbeams 96, 98,100, the geometry would cause a fulcrum that rocked the foot in a way not useful in this type of footwear. Crossbeams 96, 98,100 extend respectively within the regions of outsole 68 and midsole 84 delineated by lines 102, 104, 106. Lines 102, 104, 106 show the position of the crossbeams 96, 98,100 formed by the curving lower of midsole 84 and outsole 68 and do not exists as a palpable structures within the footwear. Depending lower from outsole 68 on the crossbeams 96, 98,100 respectively are cleat pairs 108, 110, 112. Midsole 84 material has outwardly curving portions 114, 116, 118 which fill respectively the crossbeams 96, 98,100 and contact the upper surface of outsole 78.

[0044] Crossbeam 80 and crossbeams 96, 98,100 are shown by lines 82 and 102, 104, 106 which are parallel or somewhat off parallel within each pair of lines. Thus the lower curvature of outsole 68 and midsole 84 to form crossbeam 80 and crossbeams 96, 98,100 does not need to be constant but does extend from medial edge 74 to lateral edge 76.

[0045] Outsole 68 may include foramen 130 and other foramina 132, 134 which are openings passing fully from lower surface of outsole 66 to upper surface of outsole 78 and are bordered about by outsole 68. Foramen 130 provides an opening as a hole bored or molded through outsole 68 and filled with softer material such as midsole 84 or local air but not by a harder material. The adaption provided by foramen 130 or any other foramina such as other foramina 132, 134 alone or as a group is to increase the directions for energy absorbing distortion of the outsole 68 and midsole 84 to allow stress relief between crossbeams 96, 98, within crossbeam 96, between crossbeams 80, 96, or within crossbeam 80. An additional aid to stability and traction is the optional provision of cleats 140, 142 depending lower from outsole 68 and positioned on lower surface of outsole 66 but not on any of crossbeam 80 or crossbeams 96, 98,100.

[0046] FIGS. 6A and 6B show an outsole 150 with lower surface of outsole 152. This outsole 150 is shown with a front edge 154, a rear edge 156, a medial edge 158 and a lateral edge 160 which meet at the middle of the rear edge 162 and at the middle of the front edge 164. The front edge 154, rear edge 156, medial edge 158 and lateral edge 160 of outsole 150 are shown as general reference points common to much footwear but may be extrapolated or located as would seem rational to one skilled in the art of footwear making in footwear designs in which portions of these regions are removed or changed in shape. The middle of the rear edge 162 and the middle of the front edge 164 are shown by illustrative lines which are not palpable parts of outsole 150.

[0047] The base layer 168 of the outsole 150 with lower surface of outsole 152 and a upper surface of outsole 170 which remain largely parallel but may be thickened to enclose cleat base 180 of cleat 182 around where the outsole 150 forms a part of the crossbeam 172 extending within the region of outsole 150 and midsole 174 delineated by lines 176 and arrows 178. Depending lower from outsole 150 on the crossbeam 172 is metal cleat 182. Midsole 174 material outcurve 184 fills the crossbeam 172 and contacts the upper surface of outsole 170. Cleat 182 may be of metal or other material that is attached to outsole 150 on the lower surface of outsole 152 at least partially on the surface of crossbeam 172 by such means as injection molding about the part (shown in FIG. 6B) or by thread attachment or molding together of heat softened parts.

[0048] Outsole 150 and midsole 174 are concavely curved across their width from medial edge 158 to lateral edge 160 to form crossbeam 172 and crossbeams 190, 192, 194. Crossbeams 190, 192, 194 extend respectively within the regions of outsole 150 and midsole 174 delineated by imaginary lines 196, 198, 200 and indicated by arrow pairs 202, 204, 206 respectively. Imaginary lines 196, 198, 200 show the position of the crossbeams 190, 192, 194. formed by the curving lower of midsole 174 and outsole 150 and do not exists as a palpable structures within the footwear. Depending lower from outsole 150 on the crossbeams 190, 192, 194 are cleats 208, 210, 212, 214, 216. Crossbeam 190 is shown to be curved by lines 196 and arrows 202 from medial edge 158 to lateral edge 160. Crossbeam 172 is shown to be non-linear by lines 176 and generally oriented along arrows 202 from medial edge 158 to lateral edge 160. Crossbeam 194 extends between lines 200 and is shown to be oriented at a lateral to medial oblique offset by arrows 206 from medial edge 158 to lateral edge 160 to align better with the slightly supinated position of a wearer's foot as it strikes the ground in most running gaits.

[0049] Outsole 150 has improved flexibility by way of paired notches 220, 222 positioned at or close to the edges of respective crossbeams 190, 172. Paired notches 220, 222 are paired so that one of each pair shall be on medial edge 158 and one of each pair shall be on lateral edge 160. Paired notches 220 are positioned on medial edge 158 and on lateral edge 160, and adjacent to crossbeam 190. Paired notches 222 are positioned on medial edge 158 and on lateral edge 160, and adjacent to crossbeam 172. This placement of paired notches 220, 222 close to crossbeams 190, 172 has a synergistic improvement in forefoot flexibility of the outsole 150.

[0050] Foramen 230 is positioned optionally between crossbeams 190, 172 and is bordered about by outsole 150. The opening in outsole 150 formed by foramen 230 may be filled with midsole 174 or left devoid of material. Foramen 232 is positioned to permit crossbeams 172, 192 an additional direction of easier distortion when loaded. Foramen 234 is placed through outsole 150 in between crossbeams 192, 194. Foramen 236 is bored or molded through outsole 150 in the crossbeam 194. FIGS. 7A and 7E, illustrate additional embodiments of the invention. In FIG. 7A, outsole 240 includes crossbeam 242 bearing cleats 244,246 on lower surface 248 of outsole 240 under crossbeam 242, and crossbeam 250 bearing cleats 252, 254 on lower surface 248 of outsole 240 under crossbeam 250. Crossbeam 250 is oriented at a lateral to medial oblique offset from medial edge 256 to lateral edge 258. Additional stabilizing cleats 260, 262 are provided on lower surface 248 of outsole 240 but do not extend under crossbeam 242 or crossbeam 250.

[0051] In FIG. 7B, outsole 270 includes crossbeam 272 bearing cleats 274, 276, 278 on lower surface 280 of outsole 270 under crossbeam 272. Crossbeams 282, 284 support cleats 286, 288 on lower surface 280 of outsole 270.

[0052] In FIG. 7C, outsole 290 includes crossbeams 292, 294, 296, 298, 300, 302 supporting cleats 304 on lower surface 312 of outsole 290. Cleats 304 and cleats 306, 308, 310 are of generally of the truncated conical form. Cleats 306, 308, 310 depend from crossbeams 298, 292 respectively and also extend beyond crossbeams 298, 292 onto other parts of lower surface 312 of the outsole to provide improved resistance to cleat shearing.

[0053] In FIG. 7D, outsole 320 is divided into regions of different material such as forefoot and toe region 322 of hard plastic, and midfoot and heel region 324 of rubber. Forefoot and toe region 322 includes crossbeams 326, 328 bearing spike type example cleats 330 on lower surface 332 of outsole 324 under crossbeams 326, 328. A further optional refinement to this track type sole is the inclusion of foramen 334 between crossbeam 328 and crossbeam 326.

[0054] In FIG. 7E, outsole 340 includes crossbeams 342, 344, 346 with thread attached cleats 348 attached partially on crossbeam 342 and partially off crossbeam on heel lower surface 349 of outsole 340 as an aid to sole strength at heel strike during running. Molded truncated conical cleats 350, 352, 354, 356 depend from outsole 340 under crossbeams 344 and 346. added toe off assistance is provided by toe cleat 358 on toe lower surface 360 of outsole 340. Midsole material 362 is visible through foramen 364 positioned between crossbeam 344 and crossbeam 342.

[0055] The cleated sole of the invention provides a structure that reduces discomfort from cleat pressure, provides a balanced distribution of sole elements to maintain similar sole stiffness on the medial and the lateral aspects of the sole, and produces a novel positively synergistic and unexpected interaction between the midsole, outsole and cleat elements of the sole. The sole of the invention has less weight than a sole with the same maximum midsole thickness extending throughout the expanse of the midsole lower surface. The sole crossbeams add side to side sole stiffness compared with prior art soles, and there is minimal additional manufacturing cost for the structure of the sole.

[0056] Other modifications can be made in accordance with the true spirit and scope of the invention as set forth in the claims. For example, a shell molded upper may have a sole of this invention attached by rivets or screws, the sole may be more flared medially than laterally, stabilizing side springs may be attached to the sole side walls, the lasting board may be furnished with tabs or extensions cut from the same sheet without stitching, and upper components attached thereto, or the outsole may have cushioning benefit provided by an A-Frame sole structure.

Claims

1. A device for use in an article of footwear: a sole having a medial edge and a lateral edge, a midsole mounted below the sole, the midsole having a first upper surface and a first lower surface, an outsole mounted below the midsole, the outsole having a second upper surface and a second lower surface, a plurality of crossbeams formed on the second lower surface and extending between the medial and lateral edges, and a plurality of cleats mounted below the second lower surface, at least one of the cleats being carried by at least one of of the crossbeams at a cleat location.

2. A device as in claim 1, in which the second lower surface and the second upper surface are in substantially parallel relationship, and the outsole comprises a vertically thickened portion at the cleat location.

3. A device as in claim 2, in which the one cleat comprises a spike.

4. A device as claim 1, in which at least one of the plurality of crossbeams is radiused.

5. A device as in claim 4, in which at least one of the plurality of cleats is substantially in the form of a truncated cone

6. A device as in claim 1, in which at least one of the plurality of crossbeams is of substantially constant cross-section and is substantially parallel to both the lateral and medial edges

7. A device as in claim 1, in which at least two of the plurality of cleats depend from one of said plurality of crossbeams.

8. A device as in claim 1, in which at least one region of the outsole is rubber.

9. A device as in claim 1, in which at least one region of the outsole is a plastics material.

10. A device as in claim 1, in which at least one of the cleats and the outsole are formed of the same material.

11. A device as in claim 1, in which the outsole further comprises at least one foramen.

12. A device as in claim 11, in which at least one of the foramen is located between the plurality of crossbeams.

13. A device as in claim 11, in which the outsole includes a heel, and the is comprised of the foramen.

14. A device as in claim 11, in which said outsole includes a midfoot and wherein said foramen is in said midfoot of said outsole.

15. A device as in claim 11, in which the outsole includes a forefoot and wherein the foramen is in the forefoot of the outsole.

16. A device as in claim 11, in which the outsole includes a toe area and wherein the foramen is in the toe area of the outsole

17. A device as in claim 11, in which at least one of the plurality of crossbeams is oriented at a lateral to medial offset from the lateral edge to the medial edge.

18. A device as in claim 11, in which at least one of the plurality of cleats is detachable from the outsole.

19. A device as in claim 11, in which the outsole comprises a first notch positioned close to the medial edge and a second notch positioned close to the lateral edge.