Composite cleat for athletic shoe

A composite, long wearing, slip-resistant non-metal golf cleat that alleviates damage to grass, e.g., the surface of a golf green, yet provides traction similar to conventional metal spikes is disclosed.

BACKGROUND OF THE INVENTION 
I. Field of the Invention 
The present invention relates to a cleat or spike for an athletic shoe and 
particularly to a non-metal, composite cleat for a golf shoe constructed 
from two or more polymeric materials having different densities and/or 
hardnesses. 
II. Background 
Spikes or cleats for athletic shoes have long been used to provide traction 
in dirt and grass. Such spikes or cleats typically have been made of metal 
or other relatively hard materials. 
Shoe cleats or spikes, particularly those that are removable or 
replaceable, have been known in the art for at least the last 80 years. 
Supplemental sole protectors that attach to a shoe have also been known 
for over 100 years. 
As early as 1891, prior artisans recognized the need for a supplemental 
traction device that could be attached to the bottom of a shoe. In 1891, 
Lithgow received U.S. Pat. No. 461,103 for such a sole protector. 
U.S. Pat. No. 1,237,451 to Baldwin, issued in 1817 for a supplemental 
traction device. Baldwin discloses on the front page of the patent, a 
cleat having a circular base and a plurality of transverse ribs that 
extend radially outward from a center stud or head. Baldwin describes the 
ribs as being useful for gripping the ground to enable a golfer to assume 
a steady position while making a drive. 
In 1918, Studer received French Patent No. 493,748 for a cleat having a 
circular base with a plurality of straight, radially extending ridges. The 
ridges of Studer project inwardly from the outer circumference to a raised 
central area. Moreover, Studer incorporated a threaded member on the cleat 
to screw into a shoe sole. 
In 1940, U.S. Pat. No. 2,185,397 issued to Birchfield for an athletic shoe 
cleat. The cleat of this patent is circular and utilizes a collection of 
radially extending straight ribs having flat tops. The cleats may be 
formed of a hard rubber material. 
U.S. Pat. No. 2,509,980 to McCallum, which issued in 1950, discloses a 
removable shoe cleat for use with golf shoes. The cleat has a circular or 
disk-like base. The cleat has a conical stud portion with a plurality of 
channels having rounded interiors. In addition, the cleat has three curved 
wings that radiate out from the center and which provide for the optimal 
gripping of surfaces. The cleat comprises a threaded member that screws 
into an aperture along the underside of a shoe. 
U.S. Pat. No. 2,895,235 to Melchiona, issued in 1959, describes a removable 
spike for use on sport shoes, such as golf shoes. The spike has a circular 
base and externally projecting ribs radially extending from the boss or 
slightly raised center portion of the spike. The ribs have curved sides or 
edges. The spike, which is stamped from metal, has a threaded member that 
screws into an aperture on the bottom of a shoe. 
In 1970, U.S. Pat. No. 3,512,275 was issued to Leavitt for a 
"non-penetrating" cleat arrangement. As shown in the figures of this 
patent, the cleat arrangement utilizes a plurality of straight, (actually 
broken-line) radially extending flat top ridges. 
More recently, various structures for cleats have been suggested including 
cleats having a metal or ceramic insert center surrounded by an 
elastomeric material. However, it was often found when using such cleats 
on athletic surfaces, particularly artificial turf, that the cleats of an 
athletic shoe would be subject to increased wear due to the harder insert 
supported by a relatively softer cleat body. U.S. Pat. No. 4,833,796, to 
Flemming discloses one example of such an arrangement. In this 
arrangement, a relatively stiff elastic cleat body holds a ceramic insert. 
In this manner, the ceramic portion, which is relatively very hard, makes 
contact with the playing surface, while the supporting elastic cleat body 
allows for flexibility and therefore less stressful dynamic loading of the 
athlete's foot. 
Flemming's cleat, however, does not solve a problem often encountered by 
golfers. That is the need to walk not just over greens, but also over 
smooth hard surfaces peripheral to the playing area. Like traditional 
metal cleats, on a hard surface, the Flemming cleat provides little 
traction and also does not address the additional problems of scratching 
the surfaces that are walked on, which in some areas peripheral to a golf 
course is of some concern. 
More recently, the golf cleat industry has focused on an alternative to the 
more commonly used metal golf spikes. The newer alternative spikes or 
cleats are typically formed from a non-turf penetrating, resilient 
polymeric material. These alternative cleats are often described as being 
"green-friendly" because of their non-turf penetrating nature. In addition 
to being "green-friendly", the alternative cleats have been found to be 
easier on the human body compared to previously used metal cleats. 
In Nov. 1993, U.S. Pat. No. 5,259,129 was issued to Deacon, et al. This 
patent is directed to an alternative golf cleat formed of a resilient 
plastic material which, according to Deacon, et al. "provides traction but 
does not damage the surface being walked upon." 
Since 1993, a wide variety of utility and design patents have been issued 
by the U.S. Patent and Trademark Office which are directed to various 
alternative cleat configurations. 
Clearly, from the foregoing sampling of prior art, it will be appreciated 
that removable shoe cleats or spikes, both metal and polymeric, are well 
known in the art, further, prior artisans have for many years, provided 
such cleats with a circular or disk-like base portion having a threaded 
member extending traversely therefrom. The threaded member screws into an 
aperture on the bottom of a shoe or boot. 
However, in spite of the variety of alternative cleats now available, 
improvements in cleats for athletic shoes, and particularly for golf 
shoes, are still being sought. 
SUMMARY OF THE INVENTION 
The present invention provides a cleat comprising a stud with a composite 
body for an athletic shoe that provides traction both on hard and smooth 
surfaces and on greens in a relatively non-penetrating manner. In 
accordance with one aspect of the instant invention, an exchangeable cleat 
having a non-metal body is provided. The non-metal body is formed of a 
material having first durometer (or hardness) and has a central portion 
formed of a material having a second durometer (or hardness). The central 
portion preferably extends a short distance away from a disk of 
surrounding material having a different durometer than the central 
portion, allowing (in one embodiment) a gripping central area for walking 
on harder surfaces. The wider, surrounding cleat provides traction on the 
turf, for example, during a golf swing. 
In further accordance with the invention, the removable cleat can be used 
year-round in golf without sacrificing performance and while providing 
damage avoidance to greens. 
The invention also includes athletic shoes provided with a plurality of 
dual-density cleats. Preferably, the cleats have a body that is long 
wearing and slip resistant by utilizing polymers and/or plastics. The 
non-metal, central portion preferably extends only a short distance beyond 
a surrounding turf-gripping portion, and provides non-penetrating but 
effective traction, e.g., during a golf swing. 
An additional embodiment includes a non-metal cleat having enhanced turf 
gripping properties which are imparted by a plurality of traction elements 
having arcuate ridges which grip or "bite" the turf during a golf swing. 
In preferred embodiments of the invention, the materials are selected to 
provide a long wearing, slip-resistant, non-metal golf cleat that 
alleviates damage to the surface of a golf green, yet provides traction on 
grass and wears similar to conventional metal spikes. 
These and other objects and features of the invention will be apparent from 
the following description and from the claims.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings, wherein the showings are for the purposes of 
illustrating the preferred embodiments of the invention only and not for 
purposes of limiting same, a non-metal composite cleat 2 is illustrated in 
FIGS. 1-3. The cleat is held to the sole of an athletic shoe by an 
integral stud 4. As shown in the illustrative embodiment, stud 4 
preferably comprises external mounting thread 6, allowing the stud 4 to be 
turned into one of several matingly threaded mounts in the sole of a shoe. 
A mounting tool engages the cleat body 2 at tool fittings 20 to allow the 
cleat to be firmly rotated into tight engagement within the internally 
threaded mount of the shoe. 
In an illustrative embodiment of the instant invention, the cleat is molded 
in two steps about a metal clover-shaped or "cloverleaf" base 8 as 
depicted in FIG. 3. In the first step, a disk portion 10 is molded about 
the base 8 to provide an intermediate component as depicted in FIG. 5. 
Disk 10 is shaped with a plurality of gripping sections 12, which are 
constructed and arranged to grip the turf, e.g., of a golf course during 
the player's swing, and prohibit slipping of the sole of the golf shoe. 
The disk portion preferably is also molded to form tool fittings so as to 
correspond to two of the holes 20 in the cloverleaves of base 8 surrounded 
by the wings 12. In a second molding step, a center portion 18, is formed 
preferably protruding from the upper major surface of the disk as depicted 
in FIG. 6. In use, the upper, or second, major surface is the 
ground-contacting surface. The frustoconical cavity 22 may further have 
ribs or threads 24 on the surface in order to aid in the retention of the 
center portion 18. As depicted, the frustoconical cavity 22 is convex to 
aid in the molding process, but can be concave or cylindrical. The 
relative geometric shapes of the disk portion 10 and the center portion 18 
can have any mating shape, subject only to the desire of the designer and 
the ability to manufacture the part. 
In another foreseen embodiment, the body of the cleat comprises a base 
which is attached to stud 4 and supports disk 10 at a major surface 
thereof. 
In this foreseen embodiment, the stud, base, and disk portions are formed 
integrally. As with this first illustrative embodiment, a center portion 
18, preferably protruding from the upper major surface of the disk, is 
located within the disk. 
In both of the aforementioned illustrative embodiments, the gripping 
sections 12 are raised from the base 8, and extend from the center portion 
18 to the outer edge of the disk 10. In illustrative embodiment, the 
circumference of the disk 10 is shown to comprise a shoulder area, 
rendering the disk a horizontal frustoconical section. In the illustrative 
embodiment, a typical gripping section 12 and curves down toward the base 
8 joining the straight side wall of an adjacent gripping section 12. Each 
gripping section extends outward from the center section 18 to the 
circumference of the disk. 
Preferably, the gripping section has an edge formed by the top horizontal 
surface of the disk and the straight wall. The edge preferably extends 
from the center portion 18, along a tangent to the rounded center portion, 
to the outer diameter of the disk. In the region of the cleat in which the 
tool fittings are located, segments having two substantially straight 
walls can be located to facilitate access to and use of the tool fittings. 
In the illustrative embodiment of FIGS. 1-8, the slightly higher, 
preferably rounded, center portion 18 is made of a material having a 
durometer (or hardness) which is different than the material used to make 
the disk. The different durometer of the center portion can provide slip 
resistance when walking on most hard, smooth, and/or dry surfaces. 
In additional embodiments, the gripping sections 12 may be less than, 
greater than, or equivalent to the height of the center 18. Alternatively, 
the vertical protrusions may be a combination of varying heights. 
Preferably, the durometer (or hardness) of the disk portion of the body is 
between about 60-67 on the Shore A scale (10 sec delay). More preferably 
the durometer is in the range of 55 to 75 on the Shore A scale (10 sec 
delay). The center portion preferably has a durometer of about 55-62 on 
the Shore A scale (10 sec delay). More preferably, the durometer is in the 
range of 49-65 on the Shore A scale (10 sec delay). The disk portion may 
be comprised of elastomers, plastics or other polymers and typically has a 
specific gravity of about 0.99 g/cc, more preferably in the range of 
0.85-1.05 g/cc. The center portion may be comprised of elastomers, 
plastics or other polymers and typically has a specific gravity of about 
0.95 g/cc, more preferably has a slip resistance equivalent to a better 
than 1.11/1.11 (dry/wet) on vinyl tile in accord with ASTM F-489, and an 
NBS abrasion index of about 175 or better. The disk portion is typically 
of a material having an NBS abrasion index of about 225 or better. In one 
embodiment, the material for the center portion is HP136X-60A footwear 
compound and the disk portion is HP100-X65A footwear compound, both 
purchased from UNIComp, Hampton, New Hampshire. Alternatively, the above 
referenced materials may be reversed with respect to the disc and center 
portions. 
In yet another alternative embodiment as represented in FIGS. 9-16, a cleat 
40 is provided which has a clover leaf base 96 and a non-metal body 100. 
The clover leaf base 96 is joined to an integral stud 62 which may be 
matingly mounted to mounts or receptacles in the sole of a golf shoe. 
Non-metal body 100 is comprised of a first component 41 which surrounds a 
second protruding center 48 and underlying component 54. The first 
component 41 is formed of a first material having a first durometer (or 
hardness) and the second center component 48 (which protrudes from the 
upper surface of the underlying component 54) and underlying component 54 
are formed from a second material having a second durometer (or hardness). 
Optionally, the center component 48 and the underlying component 54 may be 
formed of different materials having different durometers or hardnesses. 
In FIG. 17, a cleat cross-sectional view along line C--C of FIG. 15 
depicts an embodiment where center component 48 is separate from 
underlying component 54. 
In one embodiment, the first material may have a first durometer which is 
greater than the durometer of the second material. In an alternative 
embodiment, the first material may have a durometer which is less than the 
durometer of the second material. The first and second materials may be of 
different colors and/or compositions so that when the first material wears 
away the second material will noticeably show through (FIG. 15). 
More particularly, FIGS. 9, 10 and 14 show an alternative cleat embodiment 
40 according to the invention comprising a non-metal body 100 comprised of 
a first, outer component 41, 70 which surrounds a second central 48 and 
underlying component 54. The first and outer component 41 has traction 
gripping elements 42 which extend away from a shoe sole to form an 
outermost ground contacting surface 44. 
The outermost ground contacting surface 44 consists of an arcuate rib which 
has a rounded end 68, a central portion 66 which is a greater distance 
from base 102 than as rounded end 68, and an angular end 67 at the 
opposing end of the arcuate rib which is equidistant from base 102 as 
rounded end 68 thereby imparting a slightly curved surface to the arcuate 
rib of traction element 42, the curved surface being curved away from the 
generally flat surface of the base 102 of the cleat. Each traction 
gripping element 42 has two gradual curved slopes 45 which curve inwardly 
and downwardly to a downwardly sloping rib 46. The downwardly sloping rib 
46 extends toward the center portion of the cleat 48 from the center or 
middle of the ground contacting surface 44 of traction gripping element 
42. The downwardly sloping rib element 46 has a generally flat surface, 
functioning as a turf grabbing element for the cleat. Apertures or tool 
fittings 52 are provided for insertion of a cleat installation/removal 
tool (not shown). 
A bottom view of the cleat 40 is shown in FIG. 11 and an alternative bottom 
is shown in FIG. 11A. As seen in both FIG. 11 and FIG. 11A, a centrally 
located stud 62 is provided which may be a threaded stud as depicted in 
FIG. 11 and FIG. 11A. Raised portions 64 are present on the underside 
surface of base 102 to provide for frictional contact with the bottom of 
an athletic shoe into which the cleats are reversibly mounted or attached. 
FIGS. 12 and 12A represent a side view of the cleat of FIG. 11 and FIG. 11A 
along view lines A--A and A1--A1. Similarly, FIGS. 13 and 13A represent a 
side view of the cleat of FIG. 11 and FIG. 11A along view lines B--B and 
B1--B1. 
As can be seen in each of FIGS. 12, 12A, 13, and 13A, traction gripping 
elements 42 have an arcuate shape with central portion 66 being a greater 
distance from base 102 than either rounded end portion 68 or angular end 
portion 67 imparting a curved surface thereto. 
An exploded view of a cleat according to the invention is presented in FIG. 
14 showing an upper or top, outer or ground contact surface portion 70, a 
central underlying portion 80 and a base or sole contact portion 90. The 
upper or top, outer portion 70 consists of the first component 41 and has 
an aperture 72 for receiving the protrusion 48 from the central, 
underlying portion 80, which may extend beyond the surface 50 of outer 
portion 70. Recessed areas 74 between traction elements 42 receive 
protrusions 54 from the central underlying portion 80. 
The top, outer or ground contact surface portion 70 has apertures 73 (shown 
in dotted lines) within each of traction elements 42 for receiving 
similarly shaped elements 83 extending away from the upper surface 86 of 
the central underlying portion 80. Additionally, the upper surface 84 of 
element 83 is slightly above the outer surface 50 of the top, outer 
portion of the cleat when placed within aperture 73. 
Base element 90 is placed underneath central underlying portion 80 wherein 
two opposing apertures 94 align with apertures 82 and corresponding 
apertures 22 to form continuous holes in which a cleat 
installation/replacement tool can be used. Base portion 96 is then 
integrally molded within central, underlying portion 80. 
FIG. 15 represents a worn version of the cleat 40 with central, underlying 
portion elements 83, 84 showing when the top portion of traction elements 
42 are worn away. As indicated previously, by varying the color or 
composition of the top, outer portion 70 and central underlying portion 
80, an indication of cleat wear is visible when the color or composition 
of element 83 begins to show through. 
FIG. 16 represents a cross sectional view of the worn cleat of FIG. 15 
along view line C--C. 
In additional foreseen embodiments, the stud 62 can be metal and joined to 
the non-metal body by conventional means. The base 96 and the stud 62 can 
also be integral and formed of metal with the central underlying portion 
attached thereto by known joining methods, including mechanical fastening. 
Further, the stud 62 and/or base 96 can be made of the same material as 
the central underlying portion. Additional conventional fastening systems 
such as those described in U.S. Pat. Nos. 5,768,809, Des. 391,048 and Des. 
388,949 can also be utilized in the present invention. 
The invention also provides athletic shoes, such as golf shoes, having a 
plurality of cleats of the present invention mounted in the soles. As 
illustrated in FIGS. 7 and 8, in accord with the present invention, the 
sole of an athletic shoe is provided with a plurality mounting areas for 
the cleats. In the illustrated embodiment, the sole 30 is a molded sole 
having seven mounting areas 31 for cleats. More or less cleats can be used 
according to the specific application. Preferably, the sole also has a 
plurality of integrally molded nubs 35, which can have a variety of 
shapes. The nubs 35 provide additional stability. The mounting areas 
include an internally threaded socket or other appropriate receptacle for 
receiving the stud of the cleat. The sockets can be molded of the same 
material as the sole or can be parts of metal inserts molded into the sole 
by conventional techniques. Cleats according to any one of FIGS. 1-6 and 
9-17 may be releasably mounted in mounting area 31 of sole 30. 
Although the invention has been shown and described in detail including the 
preferred embodiments thereof, upon consideration of the disclosure 
including the drawings, those skilled in the art may make various changes, 
additions and omissions in the form and detail thereof without departing 
from the spirit and scope of the invention, as set forth in the claims.