Patent Abstract:
Adjustable traction is provided in a traction cleat by selectively restricting or not the amount of flexure permitted for a dynamic traction element on the cleat. Restricting flexure is alternatively achieved by an adjustably positionable ring or by rotating the cleat to align the dynamic element with different shoe sole topographical features. A dual locking post is provided to reduce the surface area required on the cleat hub for locking structures. The cleat is formed in a two shot molding process that permits elongations of the dynamic traction elements without sacrificing the integrity of the cleat structure.

Full Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority from U.S. Provisional Patent Application No. 60/644,532, entitled “Improved Replaceable Traction Cleat and Method of Connection” and filed Jan. 28, 2009. The disclosure of the above-mentioned provisional application is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    The present invention pertains to athletic footwear and, more particularly to athletic shoes and traction cleats for providing improved traction and comfort for the wearer of an athletic shoe. In addition, the present invention pertains to methods and apparatus for providing adjustability of the traction and comfort afforded by a cleat for a shoe, and for improving the mechanism and method for locking replaceable traction cleats in place in a receptacle mounted in the outsole of a shoe. Further, the invention relates to improving dynamic traction without sacrificing the structural integrity of a cleat. 
         [0004]    Although the preferred embodiments of the present invention are described in connection with golf shoes and cleats for golf shoes, it is to be understood that the principles of the invention apply to any shoe on which cleats or similar traction-providing devices are utilized. 
         [0005]    2. Discussion of State of the Art 
         [0006]    Historically, golf shoes were provided with traction by means of sharp metal spikes that dig into turf. After many years it was realized that these metal spikes damage the root structure of grass on golf courses, particularly on greens, and as a result, plastic cleat structures were developed so as not to damage grass blades and roots. An early example of such a cleat is found in U.S. Pat. No. 6,354,021 (Deacon et al). A refinement of the plastic traction cleat concept appears in U.S. Pat. No. 6,052,923 (McMullin &#39;923), the disclosure in which is incorporated herein by reference in its entirety. In McMullin &#39;923 there is disclosed a cleat having a hub with a threaded stem projecting from its upper surface to threadedly engage a receptacle mounted in the outsole of a shoe. The underside of the hub has plural relatively short traction protrusions, each having a height sufficient to engage blades of grass in turf to provide traction without puncturing the turf. Subsequent developments increased the length and cross section of these plastic but relatively hard traction elements. 
         [0007]    The next major development in the art of plastic traction cleats was dynamic traction elements. Specifically, as part of the dynamic traction concept, the underside of the cleat hub is provided with somewhat longer dynamic traction elements that are secured to and project downwardly and outwardly from the hub and flex to spread outwardly under the load of the weight of a wearer of the shoe to effect traction and a cushiony “feel” for the wearer. The cushiony “feel” results from the gradual spreading outwardly of the flexing traction elements as the sole of the shoe is forced against the turf or ground providing a feeling of resilience to the wearer. Examples of cleats that incorporate dynamic traction elements are found in U.S. Pat. Nos. 6,209,230 (Curley &#39;230), 6,305,104 (McMullin &#39;104) and 7,040,043 (McMullin &#39;043); the disclosures in these patents are incorporated herein by reference in their entireties. These cleats are typically secured to a threaded shoe receptacle or connector mounted in the shoe sole by means of a correspondingly threaded stem extending upwardly from the hub. 
         [0008]    Cleats having a combination of both flexible (i.e. dynamic) and relatively inflexible (i.e., static) traction elements are also known in the art. See, for example, U.S. Pat. No. 6,834,446 (McMullin &#39;446), the disclosure in which is incorporated herein by reference in its entirety. In operation, under the increasing weight of the wearer of a golf shoe during a walking step, the longer dynamic elements make initial contact with the turf and spread while deflecting toward the shoe sole. The static traction elements are configured to resist deflection when engaging the ground surface and to provide a suitable bearing for supporting weight applied through the shoe sole. The dynamic and static elements may be arranged in alternation around the hub periphery or in any symmetrical or asymmetrical array, depending on the intended static characteristics. If an asymmetrical array is used, it is known from U.S. Pat. No. 6,823,613 (Kelly et al &#39;613) to design the threaded stem, or other connecting member on the cleat, and the threaded receptacle, or other mating connector in the shoe outsole, in a cooperative manner such that the cleat has only one specific rotational orientation relative to the outsole, whereby the positions of the static and dynamic traction elements are predetermined. The disclosure in the Kelly et al &#39;613 patent is incorporated herein in its entirety. 
         [0009]    Some golfers prefer the cushiony feel of dynamic traction elements while others prefer the harder feel of static traction elements. In many cases, differences in terrain and the turf can dictate the need for a harder or softer feel and for the nature of the required traction, (i.e., whether static or dynamic or some intermediate therebetween). We have realized, therefore, that there is a need for a shoe and cleat that permits the wearer to select between harder or more cushiony “feels”, and between different levels of dynamic or static traction. 
         [0010]    It is also known in the prior art to provide a locking mechanism associated with the connection of the cleat to the shoe-mounted connector to prevent inadvertent loosening of the connection and removal of the cleat. Examples of such locking mechanisms are found in Kelly et al &#39;613 as well as U.S. Pat. Nos. 5,974,700 (Kelly &#39;700) and 7,107,708 (Kelly et al &#39;708), and in U.S. Patent Application Publication No. 2007/0209239 Kelly et al &#39;239) and the disclosures from these patents and published application are also incorporated herein by reference in their entireties. Among these locking mechanisms is one sold under the trademark FAST TWIST® comprising radially facing locking formations on the cleat and receptacle, respectively, operative to inter-engage when the stem has been screwed or otherwise rotatably engaged into the receptacle socket of the shoe-mounted connector. The locking formations on the outer wall of the internally threaded receptacle comprise an annular array of radially outward tooth-like projections, while the locking formations on the cleat include an angularly extending lead-in ramp, a recess and stop member. The tooth-like projection, during stem rotation, forcefully rides over a lead-in ramp before snapping into a recess, and then abuts the stop member to prevent the cleat from being screwed any further into the receptacle socket. The locking mechanisms allow the cleat to be unscrewed for removal and replacement upon exertion of a predetermined level of torque (i.e., typically by means of a special tool) by resilient yielding of the locking formations. The projections and lead-in ramps are typically formed on angularly-spaced, axially-extending webs surrounding the threaded stem and socket. The projection of one locking assembly may have a greater axial extent than the others, with a corresponding lead-in ramp of smaller axial extent. If this projection engages one of the other ramps, it will hold the threads of the stem and socket out of engagement, thereby preventing insertion of the threads at the wrong initial position. 
         [0011]    There are several removable cleats being commercialized that utilize both the FAST TWIST® attachment mechanism and dynamic and/or static traction elements. Typically, these cleats utilize a molded first shot base which includes a body member or hub having, on its upper surface, a threaded stem form and a circular array of locking posts angularly spaced and uniformly arranged about a circular hub. Additional polymer material is molded (i.e., a second shot) on the lower surface of the hub to provide the dynamic or static traction elements or legs that extend downwardly and outwardly from the circular hub. The dynamic traction legs, depending of factors such as their length and flexibility, provide traction by: 1) tangling with grass; 2) deflecting upwardly toward the outsole of the shoe and trapping grass between the upper surface of the traction leg and the sole of the shoe; and/or  3 ) when the shoe slips sideways, absorbing or opposing the force of the lateral slip and folding inwardly toward the cleat axis, whereby the downward or vertical extension of the elements resiliently increases from the extension in the unflexed position. 
         [0012]    Conventionally, the requirement that the dynamic traction elements extend from the periphery of the circular hub serves to restrict the downward or vertical extension that the traction element can achieve when providing traction against lateral slip. The present inventors are aware of an effort to mold dynamic legs or elements separately and then secure them to the hub by other than molding the hub and legs as an integral unit. This method, in theory, could allow the dynamic elements to be attached closer to the center of the cleat hub, thereby moving the element flexure point during lateral slip from the hub periphery to a location closer to the hub central axis. As a result, for the same overall height or vertical dimension of a cleat, the dynamic traction elements can be made longer from their proximal ends (i.e., the points of attachment to the hub) to their distal tips. The longer the lengths the dynamic traction elements, the greater is their ability to flex inward toward the axis and extend to provide increased traction during lateral slip. However, the method of separately molding the dynamic elements (as a unit) and then attaching them to the hub by means of a pin, or the like, is both costly and suffers from the possibility of the element unit becoming detached from the hub. In another aspect of the present invention we present a solution to that problem. 
         [0013]    Another limitation in the design of prior dynamic traction cleats is the need to provide a substantially solid circular hub in order to accommodate the above described FAST TWIST® locking mechanism. More specifically, the typically six FAST TWIST® locking posts disposed on the cleat hub are required to be equi-angularly spaced in a continuous array about the threaded stem in order to function in concert with the teeth on the FAST TWIST® shoe-mounted receptacle. If the hub can be configured to require less material it would reduce the cost of manufacture. A feature of the present invention addresses this issue. 
       SUMMARY OF THE INVENTION 
       [0014]    In accordance with one aspect of the present invention, the FAST TWIST® type of connector system is modified to facilitate the connection procedure, minimize the amount of material required on the cleat hub, and provide greater flexure space for dynamic traction elements. The six/twelve individual locking posts on the prior cleat are replaced with four dual locking structures, each comprising an inward facing surface forming two post sections positioned in an angularly symmetrical manner about a central recess disposed between them. Each post section includes interior and exterior ramp segments. The recess is configured to receive and retain a respective tooth of the receptacle that passes along an exterior ramp segment and then into the recess during connection of the cleat to the receptacle. The two interior ramp segments converge to form the centered recess, and the exterior segments diverge and terminate at respective ends of the dual post structure. The interior and exterior ramp segments of each post section converge inwardly and intersect to form an apex which is preferably rounded. The slope of the interior ramp segments is steeper than the slope of the exterior segments and, as a result, as the cleat is rotated into engagement with the receptacle, the teeth slide and force their way relatively easily along the more shallow slope of an exterior segment. However, once passing the apex and snapping into the recess, the teeth must pass the more steeply sloped interior ramp segments to move further relative to the dual post structure, and can do so only with the exertion of greater torque, thus enhancing the locking force opposing removal of the cleat from the receptacle. 
         [0015]    In accordance with another aspect of the present invention, the traction and feel of a cleat is adjustable. In one version of this aspect of the invention a cleat includes three parts, a base, a dynamic traction part and a separable adjustment ring that has angularly spaced projections or blocking members. The adjustability is effected by selectively positioning the ring such that the blocking members are in or out of angular alignment with the dynamic traction elements to limit or not the degree of permitted dynamic element flexure. Alternatively, instead of a separate adjustment ring, blocking members or recesses can be disposed as topographical features on the receptacle or the outsole of the shoe, and the rotational position of the cleat permits the dynamic traction elements to be selectively aligned or not with the blocking members, recesses or no topographical variation in the outsole surface. With either approach, the blocking members can be of different heights to provide selective amounts of flexure dependent on the rotational position of the ring or the cleat. This aspect of the invention may thus be broadly viewed as providing adjustable traction in an athletic shoe dynamic traction cleat by selectively adjusting the amount of flexure permitted for said dynamic traction element. 
         [0016]    In accordance with still another aspect of the present invention, the dynamic traction elements of the cleat of the present invention do not originate from the periphery of the cleat hub as in prior art dynamic cleats. Rather, the dynamic elements are part of a second shot dynamic traction portion of the molded cleat and have their roots or proximal ends originating further inboard, toward the hub central longitudinal axis, than at the hub periphery. The two-shot molding process forms an integral cleat comprising two chemically and mechanically bonded portions, namely a base portion including the cleat hub, a connector, locking members and static traction elements, and a softer more flexible dynamic traction portion including dynamic traction elements. As a result, the dynamic elements are integrally bonded to the base portion and are longer than in prior art cleats dynamic cleats, thereby adding to the flexure travel distance without sacrificing the structural integrity of the cleat. 
         [0017]    The above and still further features and advantages of the present invention will become apparent upon consideration of the following definitions, descriptions and descriptive figures of specific embodiments thereof wherein like reference numerals in the various figures are utilized to designate like components. While these descriptions go into specific details of the invention, it should be understood that variations may and do exist and would be apparent to those skilled in the art based on the descriptions herein. It is to be understood that terms such as “first”, “second”, “left”, “right” “top”, “bottom”, “vertical”, horizontal”, “front”, “rear”, “side”, “height”, “length”, “width”, “upper”, “lower”, “interior”, “exterior”, “inner”, “outer” and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a bottom view in perspective of a FAST TWIST® receptacle with which the cleats of the present invention may be utilized. 
           [0019]      FIG. 2  is a bottom view in plan of the receptacle of  FIG. 1 . 
           [0020]      FIG. 3  is a top view in plan of a cleat according to a one preferred embodiment of the present invention showing the cleat base portion, dynamic traction portion and adjustment ring and with the adjustment ring shown in the parked position. 
           [0021]      FIG. 4  is a bottom view in plan of the cleat of  FIG. 3   
           [0022]      FIG. 5  is a top view in perspective of the cleat of  FIG. 3 . 
           [0023]      FIG. 6  is a side view in elevation of the cleat of  FIG. 3 . 
           [0024]      FIG. 7  is a is bottom view in perspective of the cleat of  FIG. 3   
           [0025]      FIG. 8  is a top view of the base portion of the cleat of  FIG. 3  without the dynamic traction portion and adjustment ring for purposes of clarity. 
           [0026]      FIG. 9  is a side view in elevation of the base portion of  FIG. 8 . 
           [0027]      FIG. 10  is a bottom view in perspective of the base portion of  FIG. 8 . 
           [0028]      FIG. 11  is a top view in plan of the base portion of  FIG. 6 . 
           [0029]      FIG. 12  is a top view in plan of the dynamic traction portion of the cleat of  FIG. 3  without the base portion and adjustment ring for purposes of clarity. 
           [0030]      FIG. 13  is a side view in elevation of the dynamic traction portion of  FIG. 12 . 
           [0031]      FIG. 14  is a bottom view in perspective of the dynamic traction portion of  FIG. 12 . 
           [0032]      FIG. 15  is a bottom view in plan of the dynamic traction portion of  FIG. 12 . 
           [0033]      FIG. 16  is a top view in plan of the adjustment ring of the cleat of  FIG. 3  without the base and dynamic traction portions for purposes of clarity. 
           [0034]      FIG. 17  is a side view in elevation of the adjustment ring of  FIG. 16 . 
           [0035]      FIG. 18  is a bottom view in perspective of the adjustment ring of  FIG. 16 . 
           [0036]      FIG. 19  is a bottom view in plan of the adjustment ring of  FIG. 16 . 
           [0037]      FIG. 20  is a top view in perspective of the cleat of  FIG. 3  showing the adjustment ring in the locked position. 
           [0038]      FIG. 21  is a top view in plan of the cleat of  FIG. 20 . 
           [0039]      FIG. 22  is a bottom view in plan of the cleat of  FIG. 20 . 
           [0040]      FIG. 23  is a side view in elevation of the cleat of  FIG. 20 . 
           [0041]      FIG. 24  is a bottom view in perspective of the cleat of  FIG. 20 . 
           [0042]      FIG. 25  is a view in plan showing the cleat of  FIG. 3  without the adjustment ring secured to a shoe outsole having traction adjustment elements, and with the cleat rotationally positioned to prevent flexure of its dynamic traction elements. 
           [0043]      FIG. 26  is a diagrammatic view in section illustrating the interaction between a dynamic traction element of the cleat of  FIG. 25  and a traction adjustment element on the outsole. 
           [0044]      FIG. 27  is a view in plan similar to that of  FIG. 25  but with the cleat rotationally positioned to permit intermediate flexure of its dynamic traction elements. 
           [0045]      FIG. 28  is a diagrammatic view in section illustrating the dynamic traction element relative to the outsole for the cleat position illustrated in  FIG. 27 . 
           [0046]      FIG. 29  is a view in plan similar to that of  FIG. 25  but with the cleat rotationally positioned to permit maximum flexure of its dynamic traction elements. 
           [0047]      FIG. 30  is a diagrammatic view in section showing the dynamic traction element relative to the outsole for the cleat position illustrated in  FIG. 29 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0048]    The following detailed explanations of the drawings and of the preferred embodiments reveal the methods and apparatus of the present invention. 
         [0049]    Referring initially to  FIGS. 1 and 2 , there is illustrated a typical FAST TWIST® receptacle which is a unitary molding of plastic material including a circular plate  15  with a central hollow cylindrical boss  10  depending therefrom. The annular portion of plate  15  surrounding boss  10  serves as an anchoring flange for securing the receptacle in a shoe outsole, and is provided with an annular array of apertures  17  in which outsole material resides to assist in the anchoring function. A tiny projection  18  (which may alternatively be a recess) is located at one point of the periphery of plate  15  to permit angular orientation of the receptacle in the outsole. 
         [0050]    The inner wall of boss  10  forms an internally screw-threaded socket adapted and configured to receive and engage a mating externally threaded stem on a cleat. The thread arrangement illustrated in  FIGS. 1 and 2  is a three start thread, the lead-in points  12 ,  13  and  14  of which are angularly spaced by 120°. 
         [0051]    The receptacle includes one part of a locking arrangement for preventing inadvertent removal of the engaged cleat from the socket after full insertion without interfering with the insertion process of the cleat in the receptacle. The receptacle part of the locking arrangement includes a ring of teeth  11  formed on and extending from the outer wall of boss  10 . The teeth become engaged with locking posts on the cleat, in the manner described below, during insertion of the threaded cleat stem into the receptacle socket, and resist rotation of the stem once it is fully inserted in the socket. The teeth  11  take the form of short stubby ribs which project axially (i.e., in the direction parallel to the central rotation axis of the socket) from plate  15 . In transverse cross section the teeth  11  have a generally triangular form with a rounded apex presented to the cleat locking posts. In the illustrated embodiment the teeth are uniformly distributed co-axially about the socket axis, there being twelve such teeth disposed at intervals of 30°. 
         [0052]    The following description refers in detail to  FIGS. 3 through 24  in which a cleat according to one preferred embodiment is illustrated.  FIGS. 3-7  illustrate the entire cleat which comprises a base portion  25 , a dynamic traction portion  35  and an adjustment ring  50 . The base and dynamic portions are molded together from two different polymers as an integral unit, typically in a two shot molding process wherein the relatively hard and inflexible base portion  25  is the first shot and the softer and more flexible dynamic traction portion  35  is the second shot. These portions are bonded together chemically and mechanically during the two-shot process to assure the structural integrity of the overall cleat. The base portion includes the hub  26  of the cleat, locking posts  20 , a stem  24  with a multi-start thread for engaging the receptacle of  FIGS. 1 and 2 , and static traction elements  40  which are equally angularly spaced and project downwardly from a location adjacent the hub periphery. 
         [0053]    The polymer material used for the dynamic traction portion is preferably softer and more flexible than the polymer material used for the base portion. The adjustment ring  50  is a separate part and, as described below, is movable relative to the integrally formed base and dynamic traction portions. To facilitate understanding, in addition to the showing of the entire cleat in  FIGS. 3-7 , the base portion  25  is shown separately in  FIGS. 8-11 , the dynamic portion is shown separately in  FIGS. 12-15 , and the adjustment ring is shown separately in  FIGS. 16-19 . 
         [0054]    Referring to  FIGS. 3-7  and  FIGS. 8-11 , the base portion  25  of the cleat includes a hub  26  of generally circular configuration having an externally threaded stem  24  projecting upwardly from its upper surface concentrically about a central longitudinal axis of the cleat extending perpendicular to the top and bottom surfaces of the hub. The external threads on stem  24 , in the preferred embodiment, are configured to mate with the internal threads in the boss  10  of the receptacle illustrated in  FIGS. 1 and 2 . Four generally keyhole shaped slots  28  are defined at the hub periphery through the entire thickness of the hub, between its upper and lower surfaces, at equal angularly spaced locations. Slots  28  serve to receive polymer from the dynamic traction portion during the molding process and enhance the mechanical bond between the two portions. 
         [0055]    Angularly midway between each pair of adjacent slots  28  is one of four static traction elements  40  in the form of a generally pie shaped wedge depending from the bottom surface and the peripheral rim of the hub and extending radially outward beyond the hub periphery. The static traction elements are substantially inflexible and their bottom surfaces  41  are relatively flat in order to serve as a bearing surface when forced downwardly against the ground under the weight of a person wearing a shoe on which the cleat is mounted. The radially outer surfaces of static traction elements  40  may be arcuate about the cleat axis. The proximal ends of the top surfaces of the static elements  40  terminate at the peripheral rim of the hub at a location slightly below the hub top surface to thereby define four angularly spaced co-planar points  43  of a plane serving as an annular support shoulder on which the bottom surface of adjustment ring  50  resides. 
         [0056]    In the prior art locking arrangement between the receptacle of  FIGS. 1 and 2  and a prior art cleat, the teeth  11  engage with different ones of six or twelve equi-angularly spaced individual locking posts disposed on the cleat in an annular array that is radially spaced from the threaded cleat stem  24 . According to one aspect of the present invention, those individual locking posts are replaced with four dual locking post structures  20 . Posts  20  extend upwardly from the top surface of the hub  26  and are equally spaced angularly along that top surface at a radial location slightly inboard of the hub periphery. The radial location of the posts is such that they physically interact in the manner described below with the teeth  11  of the receptacle illustrated in  FIGS. 1 and 2 . The specific angular locations of posts  20  are such that each post is positioned substantially midway between two slots  28 . 
         [0057]    Each post  20  has a generally arcuate outwardly facing surface and an inwardly facing locking surface comprising two post sections  22 ,  23  joined by an angularly centered recess  21 . The radial location of the posts relative to the cleat central axis combine with the configuration of recess  21  to permit each recess to receive and retain a respective tooth  11  of the receptacle shown in  FIGS. 1 and 2 . Post sections  22  and  23  have respective interior ramp segments  22   a ,  23   a  proximate recess  21  that converge to form recess  21  which is located at the angular center of the post and is rounded at its nadir. Post sections  22 ,  23  also have respective exterior ramp segments  22   b ,  23   b  that mutually diverge outwardly from the hub center. The interior and exterior ramp segments of each post section intersect at a respective rounded apex  22   c ,  23   c  that faces generally toward the hub center. The angularly outer ends of ramp segments  22   b  and  23   b  terminate at respective short flat edges. Each post  20  is angularly symmetrical about an imaginary line extending radially from the cleat central axis through the nadir of recess  21 . 
         [0058]    The slope of the interior ramp segments  22   a ,  23   a  is greater than the slope of the exterior ramp segments  22   b ,  23   b ; that is, segments  22   a  and  23   a  converge at an angle that is smaller than the angle at which segments  22   b  and  23   b  diverge. As a result, as the threaded stem  24  is rotated in socket  10  ( FIGS. 1 and 2 ), teeth  11  slide relatively easily along the more shallowly sloped exterior ramp segments  22   b  or  23   b , forcing the post structure to slightly deflect radially outward in a resilient manner about its root at the top surface of the hub. However, once passing the apex  22   c  or  23   c  and reaching recess  21 , the teeth must pass the more steeply sloped interior ramp sections  22   a  or  23   a  to exit the recess, and can do so only with the exertion of greater torque applied to the cleat, thus enhancing the locking force opposing removal of the cleat from the receptacle. 
         [0059]    The configuration of each post  20  may be viewed as half an hourglass with recess  21  simulating the neck of the hourglass. This configuration of two ramp segments on each post to engage adjacent teeth on the receptacle provides the effective locking function of two of the post configurations in the prior arrangements described above. Thus, instead of the locking effect of six posts engaged with receptacle locking teeth  11 , the present invention, with four dual locking posts, has the locking effect of eight locking posts. Importantly, four symmetrical dual locking posts  20  permit the angular spacing between them to be greater than the spacing between each of the prior art six or twelve equally spaced individual locking posts. This in turn permits plastic material to be eliminated from the hub between the dual post to thereby reduce the cost of the cleat without sacrificing structural support for the posts. Moreover, as described below, the eliminated material can provide an access slot for a dynamic traction element to increase the degree of permissible flexure of that element. 
         [0060]    In accordance with another aspect of the present invention, the traction and “feel” of a cleat are adjustable. In one embodiment of this aspect of the invention the adjustment ring  50  cooperates in a selective manner with the dynamic traction portion  35  of the cleat. Referring to  FIGS. 12-15  as well as  FIGS. 3-7  and  20 - 24 , the dynamic traction portion  35  of the cleat includes a central region  31  which, in the complete cleat assembly, resides immediately beneath and axially centered with respect to hub  26 . Four dynamic traction elements  30 , spaced at equal angles, extend generally radially outward at angular positions intermediate the angular positions of static traction elements  40 . Each dynamic traction element has an arm portion that terminates in a distal traction head. The underside or bottom surface  39  of the arm portion has a proximal end located at or proximate central region  31 , well inboard of the hub periphery. The top surface  38  of the element arm has its proximal end at the hub periphery. Surfaces  38  and  39  slope outwardly and downwardly and terminate in a distal traction head. The radially outer surface  32  of the traction head is flat or just slightly arcuate and is either parallel to the cleat axis or angled slightly inwardly and downwardly. The bottom surface  33  of the traction head is either flat or may be provided with a barb, as show, to enhance traction and/or to serve as a logo to identify the cleat or shoe manufacturer. The top surface  34  of the traction head is raised from the top surface  38  of the element arm and is preferably flat for reasons described below. A short gusset  37  extends in the crotch between the inward facing surface of the traction head and the top surface  38  of the arm of element  30 . 
         [0061]    With the root or proximal end of the bottom surface  39  of each dynamic traction element  30  located proximate central region  31 , the resiliently flexible dynamic traction element is effectively suspended from that inboard location in a cantilever manner rather than from the hub periphery. As a result, the traction element has more angular space within which to flex than an element having its entire proximal end joined to the hub periphery. Such flexure may be upward toward the shoe outsole under the weight of the wearer of the shoe, or it may be downward and radially inward (i.e., back on itself) in response to lateral force against outer surface  32 . Downward and inward flexure results in resilient bending of the traction head toward the cleat axis beneath the hub, thereby extending the effective length of element  30  opposing lateral movement through grass and turf. In either case, the elongated cantilever arm resulting from attachment of the root of the dynamic traction element under surface at or near central region  31  increases the tractional capability of the element. 
         [0062]    Dynamic traction portion  35  also includes four angularly spaced guide members  36  disposed at four angularly spaced locations between the dynamic traction elements  30 . Guide member  36  are each bifurcated to form two diverging arms that extend along opposite sidewalls of a respective static traction element  40  on base portion  25  in the molded cleat unit. As the static traction element wears away, the arms of the guide members assist in providing a non-slip feature for the cleat. Specifically, the softer dynamic traction material of the guide member arms eventually contacts the ground as the static element material wears away and assists the static element in providing traction. Two of the guide members, disposed on diametrically opposite sides of central region  31 , are provided with circular openings at the vertex of the diverging arms to receive pins from a wrench that functions as a cleat installation and removal tool. 
         [0063]    Adjustment ring  50 , illustrated in  FIGS. 16-19 , as well as in  FIGS. 3-7  and  20 - 24 , is a radially short and axially thin annular member with four projections  51  that are equally angularly spaced and project radially outward and downward from the ring periphery. The adjustment ring can be secured to the base member in either of two rotational (i.e., angular) positions, namely a parked position (illustrated in  FIGS. 3-7 ) and a locked position (illustrated in  FIGS. 20-24 ). In the locked position the adjustment ring prevents the dynamic traction elements from flexing, thereby adjusting the cleat to be essentially a static traction cleat. In the parked position the adjustment ring does not interfere with flexure of the dynamic traction element. The bottom surface of ring  50  is configured to reside on the annular support shoulder defined by the proximal ends  43  of the top surfaces of the four static traction elements  40  adjacent the rim of hub  26 . Each projection  51  has a narrow bottom edge  52  at its distal end. Edge  52  is substantially planar except for an angularly centered notch  53  configured to receive and firmly engage gusset  37  located behind the traction head of a dynamic traction element  30  in the ring locked position. In this position, as illustrated in  FIGS. 20-24 , the top surface of ring  50  resides co-planar with the top surface of hub  26  and the distal end edge  52  of projection  50  projects downward into the crotch defined between the inward side of the traction head and the top surface  38  on the dynamic traction element  30 . The upper surface of projection  51  is configured to abut the bottom of a shoe outsole in which the receptacle of  FIGS. 1 and 2  is mounted, thereby preventing upward vertical movement of dynamic traction element  30 . Thus, with ring  50  in this locked position, if an upward force is applied to the dynamic traction elements, such as by the weight of a wearer of a shoe, projections  51  prevent the dynamic traction elements  30  from flexing, thereby effectively eliminating dynamic traction and providing a harder “feel” for the wearer. 
         [0064]    The parked or inactive position of adjustment ring  50  is approximately 45° displaced from the locked position and is best illustrated in  FIGS. 3-7 . In this position, projections  51  of the adjustment ring are angularly aligned with static traction elements  40 , leaving dynamic elements  30  free to flex in response to applied forces, and thereby retaining the dynamic traction capability of the cleat. The underside of projections  51  may be provided with one or more guide flanges  54  to engage one or more sides of the dynamic traction element  30  in the ring locked position or the static traction element  40  in the ring parked position. Flanges  54  facilitate positioning of the ring during positional changes and restrict inadvertent rotation of the ring once placed in either of its positions. 
         [0065]    It will be appreciated that when ring  50  is in its parked position, maximum dynamic traction element flexibility and softness of feel is effected. These dynamic traction elements, when stressed by the weight of the wearer of the shoe and not prevented from flexing, can flex in a vertical direction (i.e., upward toward the shoe sole). Thus, these elements do not spread outwardly and therefore the cleat can occupy a much smaller space on the shoe sole than cleats with conventional dynamic elements that do spread radially outward when flexed. In fact, as a result of the relatively large area of the substantially vertical outward facing surface  32  of the dynamic element traction head, horizontal forces applied to that surface when the cleat is moved laterally through grass and turf (i.e., when the wearer&#39;s shoe slips attempts to slip sideways) cause the traction head and the arm of dynamic element  30  to resiliently bend inwardly on itself as it resists such movement. 
         [0066]    Regarding the differences in “feel” and traction afforded by the two positions of adjustment ring  50 , the dynamic traction elements  30  are longer than the static elements  40 . Accordingly, when the wearer of the shoe steps down on the ground or turf, the distal ends of dynamic elements  30  make first contact with the ground. In the parked position of ring  50  (illustrated in  FIGS. 3-7 ), the dynamic traction elements  30  are free to flex and flex upwardly or vertically as described above. Hence, they gradually resiliently yield to the weight of the wearer, providing a soft feel and dynamic traction. In the locked position of ring  50  ( FIGS. 20-24 ) the projections  51  prevent significant flexure of dynamic elements  30 . Thus, the distal ends of elements  30  do not deflect and, along with static elements  40 , provide a harder feel without dynamic traction with each step taken by the wearer. 
         [0067]    It should be noted that if traction and softness of “feel” adjustability is not a desired feature for a particular cleat, the ring  50  can simply be eliminated. 
         [0068]    The adjustable traction feature of the invention is shown in the preferred embodiment to utilize locking ring  50  to selectively prevent flexure of the dynamic traction elements. It should be noted however, that the adjustable traction can be achieved without the need for a separate ring member. Specifically, it is well known that by providing suitable indexing structures in association with the threaded engagement between the cleat and its receptacle, one can selectively provide different final rotational or angular positions of the cleat relative to the shoe outsole. Multi-start threads such as described above in connection with threaded stem  24  and the threaded receptacle in  FIGS. 1 and 2 , permit multiple final rotation positions of the cleat in the receptacle. These positions are often limited, such as by providing keyways or other structure, to limit the number of permissible angular starting positions and thereby define the permissible final position(s). With this in mind, it is possible to provide suitably positioned topographical features in the outsole surface, such as flexure impeding structures or projections and flexure permissive regions or recesses that interfere with or permit flexure of the dynamic elements depending on the selected rotational position of the cleat. In fact, by providing these structures or recesses at different heights it is possible to provide for three or more degrees of flexure that depend on the angular position of the cleat in the shoe outsole. Referring to  FIGS. 2530 , an outsole  60  is provided with a repeating annular array of topographical features comprising such structures and recesses. Each array includes, in clockwise succession, a recess  61  into the outsole surface, a structure  62  depending from the outsole surface, and a blank area  63  having no structure or recess. The illustrated cleat, much like the cleat illustrated and described above, includes four equally angular spaced dynamic traction elements  72  angularly interspersed with four equally angular spaced static traction elements  71 . The height of flexure impeding structure  62  corresponds to the spacing between the outsole  60  and the traction head  73  of dynamic traction element  72  when that traction element is in its quiescent state (i.e., unflexed). The depth of recess  61  is determined by the degree of maximum flexure desired for traction element  72 . Typically, recess  61  is contoured to match the contour of traction head  73 . With four dynamic traction elements in the cleat as shown, those elements are angularly spaced by 45°. Therefore, to maintain equal spacing between recess  61  and structure  62 , and between structure  62  and the blank area  63 , such spacing would be 15°. It is to be understood that if the array includes additional structures of different heights, the spacing would be reduced accordingly. 
         [0069]    As seen in  FIGS. 25 and 26 , with the cleat position such that the unflexed dynamic elements are rotationally aligned with structures  62 , the flat upper surface of the traction head abuts the flat bottom surface of structure  62 . Accordingly, if vertical force is applied to the traction element by the weight of the wearer of the shoe, the dynamic elements  72  are incapable of flexing. In this position of the cleat, the “feel” for the wearer is relatively hard and the tractional effects are substantially static rather than dynamic. 
         [0070]    The cleat position shown in  FIGS. 27 and 28  has the dynamic traction elements  72  angularly aligned with the blank spaces  63  in each array. Vertical forces applied to traction element  72  in this cleat position cause the elements to flex until their respective traction heads abut the outsole surface. In this position the “feel” is intermediate soft and hard, and there is an intermediate dynamic component to the tractional effect. 
         [0071]    For the cleat position depicted in  FIGS. 29 and 30  the dynamic traction elements  72  are angularly aligned with recesses  61  in each array. Vertical forces applied to the dynamic elements in this position are capable of causing maximum upward deflection, permitting traction head  73  to enter recess  61 . In this position the “feel” is maximally soft, and there is a maximum dynamic component to the tractional effect. 
         [0072]    It will be appreciated that by providing suitably positioned projections and recesses on the outsole, and using a multi-start thread, multiple levels of “feel” or traction can be selectively achieved. For the embodiment of  FIGS. 25-30  the key to adjustability is the use of a multiple lead-in thread to provide different final positions of the cleat. It is possible to use any number of lead-in threads but there must be a different number of dynamic traction elements. For example, if there were three lead-in threads and three dynamic traction elements, there would be no effective difference between ending positions. For a multi-lead in of three and leg number of four or eight, there will be, by definition, different final orientations of traction elements. 
         [0073]    As is noted from  FIGS. 25 ,  27  and  29 , the hub may be provided with cutout sections  64  aligned with dynamic traction elements  72  to permit additional space for flexure of the dynamic elements. 
         [0074]    The preferred materials for the parts of the cleat are as follows: 
         [0075]    The base portion is preferably a polymer such a polyurethane having a hardness or Durometer on the order of  55 D to  65 D (on the Shore D scale). The dynamic traction portion is preferably a polymer, also typically a polyurethane, having a hardness on the order of  82 A to  90 A (on the Shore A scale). The dynamic traction portion is the second shot in a two shot molding process used to manufacture the cleat and its material is partially wrapped around the harder material in the contours of the base portion and in recess areas and slots  28  to reduce abrasion of the softer material used for the dynamic traction elements. Adjustment ring  50  is preferably Nylon to impart more stiffness, particularly when compressed in its thickness dimension. 
         [0076]    It will be appreciated that the embodiments described above and illustrated in the drawings represent only a few of the many ways of implementing the concepts of the present invention. For example, the cleat in the illustrated embodiment includes four static traction elements and four dynamic traction elements disposed symmetrically about the cleat axis. It will be understood that the number and types of traction elements and their orientation are not features of the invention other than the fact that the adjustable traction feature and the elongated dynamic traction element feature require at least one dynamic traction element. The other features of the invention apply irrespective of whether or not dynamic traction is utilized. 
         [0077]    Adjustability need not be provided for all dynamic traction elements on a particular cleat, depending on the tractional characteristics desired. Accordingly, the number of projections  51  on adjustment ring  50  and the locations of the projections  51  on adjustment ring  50  can differ from the number and locations of dynamic elements on the cleat. Likewise, in the topographical array of recess  61 , structure  62  and space  63 , the number of arrays need not track the number of dynamic traction elements, and the content of each array may be different. 
         [0078]    The adjustment ring  50  is a particularly useful structure to provide adjustable traction according to the present invention. It is to be understood however that, within the principles of the invention, other ring configurations and even non-annular structures may be attached to the cleat in different positions to selectively restrict or not restrict deflections of the dynamic traction elements. 
         [0079]    Although four dual locking posts are shown and described in the preferred embodiment, it is to be understood that the number of such posts is not a limiting feature of the invention. 
         [0080]    The preferred embodiments described herein include a threaded stem on the cleat functioning in combination with a threaded receptacle to removably attach the cleat to a shoe sole. It will be understood that the particular attachment mechanism is not a limiting feature of the invention, and that a threaded engagement is only one example of the various ways in which the cleat can be secured in an outsole-mounted receptacle in either a single angular position or in selectively alternative positions. As one example, the non-threaded Q-Fit™ attachment mechanisms disclosed in U.S. Pat. No. 6,631,571 (McMullin &#39;571) may be utilized, and the disclosure in that patent is incorporated herein by reference in its entirety. In that patent the disclosed cleat connector includes plural independent posts extending from the top surface of the cleat hub, each post having a retaining member at its distal end adapted to be received in a receptacle cavity through a respective contoured opening, after which the cleat is twisted into a locking position in the cavity. If the contours of the retaining members are different, and if the contours of the cavity openings are similarly different, specific initial and final angular positions of the cleat in the receptacle can be predetermined. Another example of an attachment mechanism that can be used is found in U.S. Pat. No. RE40,460 (Savoie &#39;460), the entire disclosure of which is incorporated herein by reference. 
         [0081]    Various features of the invention disclosed herein are mutually exclusive. For example, the adjustable traction feature does not require a two shot molding process for manufacture of the cleat, and does not require the dual locking post or any other locking arrangement. Likewise, the dual locking post feature is independent of traction adjustability and two-shot molding, and the two-shot molding feature is independent the dual locking post feature and adjustable traction. 
         [0082]    Having described preferred embodiments of a new Improved Replaceable Traction Cleat For Footwear, it is believed that other modifications, variations and changes will be suggested to those skilled in the art in view of the teachings set forth herein. It is therefore to be understood that all such variations, modifications and changes are believed to fall within the scope of the present invention as defined by the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Technology Classification (CPC): 0