BACKGROUND
The present disclosure relates to flexible grips employed on the handles of implements intended to be moved or swung with speed and force, such as, for example, sledge hammers, axes, and sporting implements such as tennis racquets and golf clubs. The disclosure particularly relates to flexible grips formed of elastomeric material and intended for the shaft of a golf club.
Heretofore, golf club grips have been provided with textured portions on the outer surface for enhancing gripping and providing for localized compression or “cushioning” to accommodate the contact pressure of the user's fingers and palm when gripping the club. Such textured portions have included depressed areas which may have portions extending transversely of the longitudinal axis of the grip or at a bias angle including configurations such as spiral or helical grooves.
Grip texture may also be raised portions. These raised portions may be ridges or domes or pillars.
Referring to FIGS. 1-3, an example of a prior art golf club grip is indicated generally at 5 and has textured portions illustrated as the cross-configured depressions indicated at 1 and 2, and the parallel spiral grooves indicated at 3. With particular reference to FIG. 3, the crossed depression 2 is shown in enlarged view having the edges thereof formed by transversely or radially extending voids of the groove indicated by reference number 4. The grip is of the type formed with an open end, illustrated on the left side in FIG. 1 and a substantially closed end distal the left side.
FIG. 4 is another example of prior art showing raised portions. These portions may be raised circles or squares, or any cross-sectional shape. The height of the raised portions may be 0.3 mm-1.0 mm with diameters ranging from 0.5 mm-1.0 mm. The raised portions may also be ridges that project circumferentially, longitudinally, or wrap in a spiral fashion around the grip.
With reference to FIG. 6, another prior art version of a golf club grip, indicated generally at 6 has a textured surface shown in the form of a V-shaped depression or groove indicated by reference numeral 6.
The existing manufacture of such elastomeric grips for golf clubs employs molding either by compression or injection, and thus requires the formation of the molds having reverse image surfaces for forming the textured surfaces on the molded grip. Presently, metal machining technologies have limited the configuration of the textured surfaces.
The formation of the textured surfaces on a grip has heretofore provided for a diverse range of performance advantages. Included in such advantages are localized “cushioning” or resilience, i.e., compression under the user's grip to enhance the contact area of the user's palm and fingers with the grip; slip resistance between the grip and hands when moved with speed on downswing; and adhesion of the internal surface of the grip to the shaft. Thus, it has been desired to provide these performance advantages with grip texture that offers improved performance.
SUMMARY
The present disclosure describes grip texture advancements which are possible with advanced tool making technologies.
The present disclosure provides an improved tubular elastomeric grip for an implement, and particularly for a golf club and formed with an open end and a substantially closed end. One disclosed version includes grooves or depressions formed in the outer surface having the sides of the depression or groove forming a sharp edge with the surface of the grip by virtue of an undercut or an acute angle formed with the side wall of the depression.
In another version, the groove or depression may be formed with the walls substantially parallel and inclined to the axis of the grip so that a sharp edge from an undercut at an acute angle is provided on the surface of the grip and the sharp edge is oriented in a direction toward the club head to provide enhanced grip engagement with the user's fingers and palm and to provide for increased localized “cushioning” or compressibility in a radial direction to provide increased surface contact with the user's hands.
In another version of the disclosed grips, the tubular elastomeric member includes undercut grooves formed on the inner periphery of the grip which portions engage the surface of the implement handle and serve to provide increased compressibility or “cushioning” in the radial direction to enable localized deformation of the grip to accommodate the user's hand and thereby enhance gripping.
Another version is to provide slip resistance using raised portions to create edges that engage the skin of the hand, resisting slipping. Heretofore these textures have been limited to a general dimension of approximately 0.5 mm-2.0 mm in width and height. It is desirable to reduce the size of texture to less than 0.3 mm, therefore increasing the number of edges and geometries to improve slip resistance. The exterior or interior of the grip may have a microtexture which is defined as having raised portions not greater than 0.3 mm in transverse section or diameter with a height proportionately larger by approximately 2×, therefore at 0.6 mm in height. The ratio of diameter to height may vary as well as spacing between the raised portions.
In another version, the raised portion may include a rough or sharp texture, with peaks having a radius less than 0.2 mm. The valleys between the peaks may also be provided with an included angle having a radius less than 0.2 mm. The distance between the peaks and valleys may vary. A greater distance will increase the flexibility or “cushioning” of the raised portions.
In another version, the microtexture may be formed on the inner surface of the grip. The microtexture can offer dry adhesion benefits, allowing the grip to be installed on a club shaft without double faced tape.
In another version, the grip of the present disclosure is formed with enclosed voids or hollow spaces within the wall of the tubular member to provide improved localized radial compressibility or “cushioning” for the grip to enhance gripping. The grip of the present disclosure may be satisfactorily formed by laser machining or additive manufacturing (AM), also known as “3-D printing”.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a flexible grip as employed in the prior art;
FIG. 2 is an enlarged view of a portion of FIG. 1;
FIG. 3 is a sectional view taken along section indicating lines 3-3 of FIG. 1;
FIG. 4 is a sectional view showing raised portions;
FIG. 5 is a cross-section of one version of a grip of the present disclosure illustrating the undercut voids of a groove formed therein;
FIG. 6 is a perspective view of another version with portions broken away to shown V-shaped grooves as employed in a prior art grip;
FIG. 7 is a view similar to FIG. 6 of another version of the grip of the present disclosure illustrating the undercut side walls of the grooves;
FIG. 8 is a perspective view of another version of the grip of the present disclosure showing textured portion in the form of raised peaks having a radiused apex;
FIG. 9 is a cross-section taken through the longitudinal axis of another version of the grip of the present disclosure employing grooves on the inner periphery having undercut side walls;
FIG. 10 is a view similar to FIG. 9 and shows another version of the grip of the present disclosure having closed voids or spaces formed within the wall of the tubular member; and
FIG. 11 is a portion of a transverse cross-section of another version of the grip of the present disclosure showing a groove in a textured portion having a groove with parallel sides angled with respect to the outer surface such that one outer side wall edge forms an acute angle with the outer surface.
FIG. 12 is a perspective view of a portion of a surface of a grip showing a microtexture of raised portions.
DETAILED DESCRIPTION
Referring to FIG. 5, a portion of one version of the flexible grip disclosed herein is illustrated in cross-section taken transverse to the length thereof, and indicated generally at 10 and is of the type formed of a tubular member 11 having an open end (not shown) and a substantially closed end (not shown). A portion of a transverse cross-section is shown and has the outer surface 12 thereof having a textured portion comprising a groove 14 having the sides 16, 18 thereof forming oppositely disposed acute angles at the outer edge with the surface 12 of the grip. Thus, upon the user gripping the elastomeric grip 10, the acute angle edges of the undercut groove sides are permitted to be flexed somewhat inwardly to provide localized “cushioning” deformation and improved surface contact with the user's hands; and, the acute angle edge also provides greater gripping in the direction of the longitudinal axis of the implement and particularly, in the case of a golf club grip.
FIG. 7 shows another version of the flexible grip of the present disclosure indicated generally at 20 and employs undercut groove 22 at a bias angle or having a spiral or helical configuration on the grip with the side walls 24, 26 thereof undercut, thereby providing enhanced localized “cushioning” or compressibility and improving gripping of the club by the user.
Referring to FIG. 8, another version of the flexible grip of the present disclosure is indicated generally at 30 and has a textured portion comprising a plurality of adjacent raised peaks and valleys formed on the outer surface of a tubular member 31 and having the apexes thereof denoted by reference numeral 32 formed to a radius to give improved gripability. The height of the adjacent peaks in the direction radially with respect to the tubular member may be varied if desired. In the present practice, it has been found satisfactory to have the radius of the peaks and valley in the range of 0.02 to 0.2 mm. It will be understood that the adjacent peaks may have different heights to enhance gripability.
Referring to FIG. 9, another version of the flexible grip of the present disclosure is indicated generally at 50 and has the tubular member 52 thereof formed having a plurality of longitudinally spaced annular or spiral wrapped grooves shown in two different widths 54, 56 formed on the inner periphery 62 thereof for engaging the handle of the implement such as a golf club shaft. The grooves 54, 56, have the sides 58, 60 respectively thereof undercut and inclined so as to each form an acute angle with the inner periphery 62 of the tubular member. The grooves 54, 56 thus provide improved “cushioning” or compressibility in the radial direction in localized regions longitudinally of the grip for improving the surface contact of the grip of the user's hand.
Referring to FIG. 10, another version of the flexible grip of the present disclosure is indicated generally at 70 and has the tubular member 72 formed of elastomeric material with longitudinally spaced enclosed voids or spaces, or pockets formed in a longitudinally extending row intermediate the inner and the outer periphery as denoted by reference numeral 74. The spaces 74 or voids thus provide localized thinning of the wall of the tubular member 72 to permit improved localized “cushioning” or compression in the radial direction to thereby increase the surface contact area with the user's hand and improve gripping.
Referring to FIG. 11, another version of the grip of the present disclosure is indicated generally at 80 and comprises a tubular member 81 having a textured portion on the outer surface 82 thereof including at least one groove 84 having the sides 86, 88 thereof disposed in parallel arrangement and angled with respect to the longitudinal axis of the grip and having one of the oppositely disposed outer edges 86 forming an acute angle with the outer surface of the grip at its outer edge. The side 86 of the groove is intended to be disposed oriented on the surface of the grip such that the angled outer edge of side 86 is directed toward the club head of the golf club grip to enhance gripping by the user's hand. The angled side 86 also provides improved compressibility and localized deformation or “cushioning” thereabout upon the user gripping the club to improve the surface contact area.
Referring to FIG. 12, another version of the grip texture indicated generally at 40 is shown having a microtexture on a surface thereof where each raised portion indicated typically at 42 is a cylinder of diameter less than 0.3 mm and a height in proportion to the diameter, ranging from 2× to 5× the diameter. The spacing between the cylinders is approximately 2×-5× the diameter of the cylinders. This microtexture may vary in diameter, height, and spacing. The microtexture may be on the exterior surface of the grip, the interior surface of the grip, or both.
In the present practice, it has been found expeditious to form the various versions of the elastomeric grip described hereinabove by either laser machining or additive manufacturing (AM), also known as “3-D printing” employing progressively depositing incremental layers of the elastomeric material. This process can achieve heretofore unobtainable radii of as small as 0.2 mm and particularly lends itself to the formation of the versions having undercut grooves and enclosed voids or hollow spaces as shown in FIGS. 7, 10, 11, and 12.
The elastomeric grip of the present disclosure provides versions for localized improved “cushioning” compressibility or deformation in a radial direction, particularly for golf club grips, by utilizing undercut depressions to form textured portions on the outer surface of the grip. Another version provides improved localized “cushioning” and compressibility by providing undercut grooves on the inner periphery which contacts the handle of the implement or golf club shaft.
The tooling may also be produced by laser machining or additive manufacturing, e.g., “3-D printing”. Either method is capable of the resolution needed to produce the microtexture or the undercuts in the tooling.
The exemplary embodiment has been described and illustrated with reference to the drawings. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.