MULTI-LAYER MATERIAL ADAPTED TO DISSIPATE AND REDUCE VIBRATIONS

[0001] MULTI-LAYER MATERIAL ADAPTED TO DISSIPATE

AND REDUCE VIBRATIONS

[0002] CROSS REFERENCE TO RELATED APPLICATIONS

[0003] This application is a Patent Cooperation Treaty application that claims priority to the following four U.S. Patent Applications: [1] U.S. patent application

10/173,063, filed on June 17, 2002, whichis hereby incorporatedby reference herein as if fully set forth in its entirety; [2] U.S. Patent Application 10/165,748, filed on

June 7, 2002, which is hereby incorporated by reference herein as if fully set forth

in its entirety; [3] U.S. Patent Application 10/346,954, filed on January 17, 2003

which is hereby incorporated by reference herein as if fully set forth in its entirety;

and [4] U.S. Patent Application 10/360,353, filed on February 7, 2003 which is

hereby incorporated by reference herein as if fully set forth in its entirety.

[0004] BACKGROUND

[0005] The present invention is directed to a material adapted to reduce

vibration and, more specifically, to a multi-layer material adapted to dissipate and evenly distribute vibrations transmitted to one side of the material.

[0006] Handles of sporting equipment, bicycles, hand tools, etc. are often made of wood, metal or polymer that transmit vibrations that can make the items

uncomfortable for prolonged gripping. Sporting equipment, such as bats, balls, shoe

insoles and sidewalls, also transmit vibrations during the impact that commonly occurs during athletic contests. These vibrations can be problematic in that they

can potentially distract the player's attention, adversely effect performance, and/or

injure a portion of a player's body. ,

[0007] Rigid polymer materials are typically used to provide grips for tools

and sports equipment. The use of rigid polymers allows users to maintain control

of the equipment but is not very effective at reducing vibrations. While it is known

that softer materials provide better vibration regulation characteristics, such materials do not have the necessary rigidity for incorporation into sporting equipment, hand tools, shoes or the like. This lack of rigidity allows unintended

movement of the equipment encased by the soft material relative to a user's hand

or body.

[0008] Prolonged or repetitive contact with excessive vibrations can injure a

person. The desire to avoid such injury can result in reduced athletic performance and decreased efficiency when working with tools.

[0009] Clearly what is needed is a multi-layer material adapted to regulate

vibration that provides the necessary rigidity for effective vibration distribution;

that can dampen and reduce vibrational energy; and that preferably uses materials having Shore A durometers designed for superior vibration dissipation without compromising a p erson's ability to manipulate an object incorporating the material.

[0010] SUMMARY

[0011] One embodiment of the present invention is directed to a material adapted to regulate vibration. The material includes first and second elastomer layers. A cloth layer is disposed between and generally separates the first and second elastomer layers. The cloth layer is formed of a plurality of woven aramid fibers.

[0012] In another aspect, the present invention is directed to a composite material adapted to regulate vibrations. The composite material has three

generally independent and separate layers including first and second elastomer layers. A cloth layer is disposed between and generally separates the first and second elastomer layers. The cloth layer is formed of a plurahty of woven aramid

fibers.

[0013] In another aspect, the present invention is directed to a material

adapted to regulate vibration. The material has three generally independent and distinct layers including first and second elastomer layers. A cloth layer is disposed

between and generally separates the first and second elastomer layers. The cloth

layer is formed of a plurahty of woven aramid fibers. At least some of the plurahty of woven aramid fibers are capable of moving relative to the cloth layer to allow at

least some movement of the first elastomer layer relative the second elastomer

layer.

[0014] In another aspect, the present invention is directed to a composite

material adapted to regulate vibration. The composite material has three generally

distinct layers including first and second elastomer layers. A layer formed by a plurahty of aramid fibers is disposed between and generally separates the first and

second elastomer layers. The first elastomer layer is capable of least some movement relative to the second elastomer layer to dissipate vibration by

converting vibration to heat.

[0015] In another aspect, the present invention is directed to a material

adapted to regulate vibration. The material has two independent layers including

a first elastomer layer. A cloth layer is disposed on the first elastomer layer. The

cloth layer is formed of a plurahty of woven aramid fibers.

[0016] In another aspect, the present invention is directed to an implement

having a handle at least partially enclosed in a material adapted to regulate

vibration. The implement includes ahandlebodyhavingalongitudinalportion and

a proximal end. The material encases at least some of the longitudinal portion and

the proximal end of the handle. The material has at least two generally separate

and distinct layers including a first elastomer layer and a cloth layer disposed on

the elastomer layer. The cloth layer is formed of woven aramid fibers.

[0017] In another aspect, the present invention is directed to a grip for an

implement having a handle with a proximal handle end. The grip includes a tubular shell having a distal open end adapted to surround the portion of the handle

and a closed proximal end adapted to enclose the proximal end of the handle. The tubular shell is formed of a material adapted to regulate vibration. The material

has at least two generally separate layers. The material includes a first elastomer layer and a cloth layer disposed on the elastomer layer. The cloth layer is formed of woven aramid fibers.

[0018] In another aspect, the present invention is directed to a grip for an implement having a handle with a proximal handle end. The grip including a tubular shell having a distal open end adapted to surround a portion of the handle

and a closed proximal end adapted to enclose the proximal end of the handle. The tubular shell is formed of a material adapted to regulate vibration. The material

has at least two generally separate layers. The material includes a first elastomer layer and a layer formed by a plurahty of fibers disposed on the elastomer layer.

[0019] In another aspect, the present invention is directed to a grip for an implement having a handle. The grip includes a tubular shell adapted to surround a portion of the handle. The tubular shell is formed of a material adapted to

regulate vibration. The material has at least two generally separate layers. The material includes a first elastomer layer and a cloth layer disposed on the elastomer

layer. The cloth layer is formed of woven aramid fibers.

[0020] BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The foregoing summary, as well as the following detailed description

of the preferred embodiments of the present invention will be better understood

when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It is understood, however, that the invention is not limited to the precise arrangements and instrumentality shown. In the drawings:

[0022] Figure 1 is a cross-sectional view of a preferred embodiment of the

material of the present invention; and

[0023] Figure 2 is perspective view of the material of Figure 1 configured to

form a grip. [0024PETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Certain terminology is used in the following description for convenience only and is not limiting. The term "implement," as used in the

specification and in the claims, means "any one of a baseball bat, racket, hockey stick, Softball bat, sporting equipment, firearm, or the like." The above terminology

includes the words above specifically mentioned, derivatives thereof, and words of similar import. Additionally, the words "a" and "one" are defined as including one

or more of the referenced item unless specifically stated otherwise.

[0026] Referring to Figures 1 and 2, wherein like numerals indicate like

elements throughout, there is shown a preferred embodiment of a material adapted

to regulate vibration according to the present invention, generally designated 10. Briefly stated, the material 10 of the present invention is a multi-layer material

formed by at least a first elastomer layer 12A and a layer of aramid fibers 14. The

material 10 canbeincorporatedinto athletic gear, grips for sports equipment, grips

for tools, and protective athletic gear. More specifically, the material 10 can be used: to form grips for a tennis racquet, hockey sticks, golf clubs, baseball bats or

the like; to form protective athletic gear for mitts, headbands, helmets, gloves,

pads, or the like; to form seats or handle bar covers for bicycles, motorcycles, or the like; to form boots for skiing, roller blading or the like; to form footwear, such as

shoe soles and inserts; to form grips for fire arms, han guns, rifles, shotguns, or the

like; and to form grips for tools such as hammers, drills, circular saws, chisels or the

like. [0027] The first elastomer layer 12A acts a shock absorber by converting

mechanical vibrational energy into heat energy. The aramidfiber layer 14 redirects vibrational energy and provides increased stiffness to the material 10 to facihtate a user's ability to control an implement 20 encased, or partially encased, by the

material 10.

[0028] It is preferred that the composite material 10 have three generally

independent and separate layers including the first elastomer layer 12 A and a second elastomer layer 12B. Elastomer material provides vibration damping by

dissipating vibrational energy. Suitable elastomer materials include, but are not hmited, urethane rubbers, sihcone rubbers, nitrile rubbers, butyl rubbers, acryhc

rubbers, natural rubbers, styrene-butadiene rubbers, and the hke. In general, any

suitable elastomer material can be used to form the first and second elastomer

layers without departing from the scope of the present invention. [0029] The softness of elastomer materials can be quantified using Shore A

durometer ratings. Generally speaking, the lower the durometer rating, the softer the material and the more effective an elastomer layer is at absorbing and

dissipating vibration because less force is channeled through the elastomer. When a soft elastomer material is squeezed, an individual's fingers are imbedded in the

elastomer which increases the surface area of contact between the user's hand and creates irregularities in the outer material surface to allow a user to firmly grasp

any implement 20 covered, or partially covered, by the material. However, the

softer the elastomer layers 12A, 12B, the less control a user has when manipulating an implement 20 covered by the elastomer. If the elastomer layer is too soft (i.e., if the elastomer layer has too low of a Shore A durometer rating), then the implement 20 may rotate unintentionally relative to a user's hand or foot. The material 10 of the present invention is preferably designed to use first and second elastomer layers 12A, 12B having Shore A durometer ratings that provide an

optimum balance between allowing a user to precisely manipulate and control the implement 20 and effectively damping vibration during use of the implement 20.

[0030] It is preferable, but not necessary, that the elastomer used with the

material 10 have a Shore A durometer of between approximately ten (10) and

approximately eighty (80). It is preferred that the first elastomer layer have a

Shore A durometer of between approximately ten (10) and approximately twenty-

five (25) and that the second elastomer layer has a Shore A durometer of between approximately twenty-five (25) and approximately forty-five (45).

[0031] The first elastomer layer 12A is preferably used to absorb vibrational

energy and to convert vibrational energy into heat energy. The second elastomer layer 12B is also used to absorb vibrational energy, but also provides a compliant

and comfortable grip for a user to grasp (or provides a surface for a portion of a user's body, such as the under sole of a user's foot when the material 10 is formed

as a shoe insert).

[0032] In one embodiment, the first elastomer layer 12Apreferably has Shore

A durometer of approximately fifteen (15) and the second elastomer layer has a

Shore A durometer of approximately forty- two (42). If the first and second

elastomer have generally the same Shore A durometer ratings, then it is preferable, but not necessary, that the first and second elastomer layers 12A, 12B have a Shore A durometer of fifteen (15), thirty-two (32), or forty-two (42).

[0033] The fiber layer 14 is preferably, but not necessarily, formed of aramid fibers. The fibers can be woven to form a cloth layer 16 that is disposed between and

generally separates the first and second elastomer layers 12 A, 12B. The cloth layer 16 can be formed of aramid fibers or other types of fiber. The cloth layer 16

preferably generally separates the first and second elastomer layers 12A, 12B causing the material 10 to have three generally distinct and separate layers 12 A,

12B, 14. The aramid fiber layer 14 blocks and redirects vibrational energy that

passes through one of the elastomer layers 12 A or 12B to facihtate the dissipation

of vibrations. The aramid fibers 18 redirect vibrational energy along the length of

the fibers 18. Thus, when the plurahty of aramid fibers 18 are woven to form the cloth layer 16, vibrational energy emanating from the implement 20 that is not

absorbed or dissipatedby the first elastomer layer 12Ais redistributed evenly along

the material 10 by the cloth layer 16 and then further dissipated by the second

elastomer layer 12B.

[0034] It is preferable that the aramid fibers 18 be formed of a suitable polyamide fiber of high tensile strength with a high resistence to elongation.

However, those of ordinary skill in the art will appreciate from this disclosure that any aramid fiber suitable to channel vibration can be used to form the aramid fiber

layer 14 without departing from scope of the present invention. Additionally, those

of ordinary skill in the art will appreciate from this disclosure that loose aramid

fibers or chopped aramid fibers can be used to form the aramid fiber layer 14 without departing from the scope of the present invention. The aramid fibers may also be formed of fiberglass.

[0035] When the aramid fibers 18 are woven to form a cloth layer 16, it is preferable that the cloth layer 16 include at least some floating aramid fibers 18.

That is, it is preferable that at least some of the plurahty of aramid fibers 18 are

able to move relative to the remaining aramid fibers 18 of the cloth layer 16. This

movement of some of the aramid fibers 18 allows at least some movement between

the first elastomer layer 12 A and the second elastomer layer 12B. This movement of the first elastomer layer 12 A relative to the second elastomer layer 12B converts

vibrational energy to heat energy. Such motion is preferably facihtated by the first and second elastomer layers 12A, 12B only being joined at discreet locations rather

than being continuously joined along a common interface. This discrete contact between the first and second elastomer layers 12A, 12B at discreet locations results in the elastomer layers 12A, 12B moving relative to one another and further

dissipating vibration.

[0036] Those of ordinary skill in the art will appreciate from this disclosure

that the material 10 can be formed of two independent layers without departing

from the scope of the present invention. Accordingly, the material 10 can be formed

of a first elastomer layer 12A and an aramid fiber layer 14 (which may be woven

into a cloth layer 16) that is disposed on the first elastomer 12A. [0037] The material 10 may be configured and adapted to form an insert for

shoe. When the material 10 is configured to form a shoe insert, the material 10 is preferably adapted to extend along an inner surface of the shoe from a location proximate to a heel of the shoe to the toe of the shoe. In addition to forming a shoe

insert, the material 10 can be located along the sides of a shoe to protect the wearer's foot from lateral impact.

[0038] The material 10 may be configured and adapted to form a grip 22 for an implement such as a bat, having a handle 24 and a proximal end 26 (i.e., the end

proximal to where the bat is normally gripped). The material 10 is preferably adapted to enclose a portion of the handle 24 and to enclose the proximal end 26 of

the bat or implement 20. As best shown in Figure 2, it is preferable that the grip

22 be formed as a single body that completely encloses the proximal end of the implement 20. The material 10 may be also be configured and adapted to form a

grip 22 for a tennis racket or similar implement 20 having a handle 24 and a

proximal end 26.

[0039] While the grip 22 willbe described below in connection with a baseball

or Softball bat, those of ordinary skill in the art will appreciate that the grip 22 can be used with any of the equipment, tools, or devices mentioned above without

departing from the scope of the present invention.

[0040] When the grip 22 is used with a baseball or softball bat, the grip 22

preferably covers approximately seventeen (17) inches of the handle of the bat as

well as covers the knob (i.e., the proximal end 26 of the implement 20) of the bat.

The configuration of the grip 22 to extend over a significant portion of the bat length contributes to increased vibrational damping. It is preferred, but not necessary,

that the grip 22 be formed as a single, contiguous, one-piece member. [0041] Thebaseballbat (or implement 20) has ahandle 24including ahandle body 28 having a longitudinal portion 30 and a proximal end 26. The material 10

preferably encases at least some of the longitudinal p ortion 30 and the proximal end 26 of the handle 24. The material 10 can be produced as a composite having two generally separate and distinct layers including a first elastomer layer 12A and an

aramid fiber layer 14 (which may be a woven aramid cloth layer 16) disposed on the

elastomer layer 12A. The aramid fiber layer 14 is preferably formed of woven aramid fibers 18. The second elastomer layer 12B may be disposed on a major

surface of the aramid fiber layer 14 opposite from the first elastomer layer 12A.

[0042] As best shown in Figure 2, a preferred grip 22 is adapted for use with

an implement 20 having a handle and a proximal handle end. The grip 22 includes

a tubular shell 32 having a distal open end 34 adapted to surround a portion of the handle and a closed proximal end 36 adapted to enclose the proximal end of the

handle. The tubular sheU 32 is preferably formed of the material 10 which dissipates vibration. The material 10 preferably has at least two generally separate

layers including a first elastomer layer 12A and an aramid fiber layer 14 (which

fibers 18 may be woven to form a cloth layer 16) disposed on the first elastomer

layer 12A.

[0043] Multiple methods can be used to produce the comp osite or multi-layer

material 10 of the present invention. One method is to extrude the material by pulling an aramid fiber cloth layer 16 from a supply roll while placing the first and

second elastomer layers 12 A, 12B on both sides of the woven aramid cloth layer 16. A second method of producing the material 10 of the present invention is to mold the first elastomer layer 12A onto the implement 20, then to weave an aramid fiber layer thereover, and then to mold the second elastomer layer 12B thereover. Alternatively, a cloth layer 16 can be pressured fit to an elastomer layer to form the

material 10. Those of ordinary skill in the art will appreciate from this disclosure

that any known method of making composite or multi -layer materials can be used

to form the material 10.

[0044] The covering of the proximal end of an implement 20 by the grip 22 results in reduced vibration transmission andin improved counter balancing of the

distal end of the implement 20 by moving the center of mass of the implement 20

closer to the hand of a user (i.e., closer to the proximal end 26). This facilitates the swinging of the implement 20 and can improve sports performance while reducing

the fatigue associated with repetitive motion.

[0045] It is recognized by those skilled in the art, that changes may be made to the above -described embodiments of the invention without departing from the

broad inventive concept thereof. For example, the material 10 may include

additional layers (e.g., five or more layers) without departing from the scope of the

claimed present invention. It is understood, therefore, that this invention is not

hmited to the particular embodiments disclosed, but is intended to cover all

modifications which are within the spirit and scope of the invention as defined by the appended claims and/or shown in the attached drawings.