Golf club head with gasket

A golf club (40) having a club head (42) with a face component (60), an aft body (61) and a gasket (300) is disclosed herein. The face component (60) has a striking plate portion (72) and a return portion (74). The aft-body (61) is preferably composed of a crown portion (62), a sole portion (64) and optionally a ribbon section (90). The gasket (300) provides an interface between the face (60) and the aft-body (61) that reduces corrosion and improves manufacturing costs of the club head. The club head (42) preferably has a volume in the range of 290 cubic centimeters to 600 cubic centimeters, a weight in the range of 165 grams to 300 grams, and a striking plate portion (72) surface area in the range of 4.00 square inches to 7.50 square inches.

FEDERAL RESEARCH STATEMENT

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates to a golf club head with a face component, an aft-body and a gasket disposed between the face component and aft-body. More specifically, the present invention relates to a golf club head with a face component, an aft-body and a gasket disposed between the face component and aft-body to create an improved barrier between the face and body of the golf club head.

2. Description of the Related Art

Golf clubs can be manufactured in several ways. One approach is to bond a face component to a separate body using an adhesive. In this operation, the dispersion and application of the adhesive and removal of any residual adhesive results in increased costs. Additional cosmetics, such as a trim line between the mated face components and body may require filler material that must be cured and cleaned after cure. The additional steps and materials increase manufacturing time as well as the likelihood of introducing defects to the manufacturing process. The quality of the finished product is dependant on the relative skill of the worker. Moreover, the combination of dissimilar materials in the face and body can increase the likelihood of corrosion. Thus, in many golf club heads, the manufacturing processes require increased labor and skill and are subject to the effects of corrosion between dissimilar materials.

In order to improve the performance of golf club heads, many golf club manufacturers produce golf clubs with separate face plates that are bonded to the golf club body. However, there is a need for a golf club head with a face-body interface that is more corrosion resistant than that of a conventional golf club and provides cost savings.

SUMMARY OF INVENTION

The present invention provides a solution to the cost-effective production of golf clubs while providing golfers with golf clubs that they currently play and trust to give them optimal performance. The present invention is able to accomplish this by providing a wood-type golf club head with an insert for improved barrier and corrosion resistance between the golf club face and body.

The present invention overcomes problems of the prior art by providing a golf club head that comprises a face component, an aft-body and a gasket disposed between the face component and the aft-body. The gasket creates an improved barrier for reducing corrosion, while reducing assembly time and improving consistency among golf club heads.

In accordance with an embodiment of the invention, a golf club head includes a face includes a face component, an aft-body and a gasket. The face component has a striking plate portion and a return portion. The aft body, which includes a crown portion and a sole portion, is attached to the return portion of the face component. The gasket is positioned in a gap between the face component and the aft-body. The gasket may be composed of a polymer material, such as a thermoplastic polyurethane elastomer material. The gasket preferably has a width in the range of 0.010 inch to 0.020 inch. Different portions of the gasket may have different cross-sectional configurations.

DETAILED DESCRIPTION

As shown inFIG. 1, a golf club is generally designated40. The golf club40has a golf club head42. Engaging the club head42is a shaft48that has a grip50, not shown, at a butt end52and is inserted into a hosel54at a tip end56.

As shown inFIGS. 1A-8, the club head42is generally composed of a face component60, an aft-body61and a gasket300. As explained in greater detail below, the gasket300is disposed between the face component60and the aft-body61. The aft-body is preferably composed of an upper section200and a lower section202, which are joined together to form the aft-body61. The aft-body61preferably has a crown portion62and a sole portion64. The golf club head42is preferably has a heel end66nearest the shaft48, a toe end68opposite the heel end66, and a rear end70opposite the face component60.

The face component60is generally composed of a single piece of metal, and is preferably composed of a forged metal material. More preferably, the forged metal material is a forged titanium material. Such titanium materials include pure titanium and titanium alloys such as 6-4 titanium alloy, SP-700 titanium alloy (available from Nippon Steel of Tokyo, Japan), DAT 55G titanium alloy available from Diado Steel of Tokyo, Japan, Ti 10-2-3 Beta-C titanium alloy available from RTI International Metals of Ohio, and the like. Other metals for the face component60include stainless steel, other high strength steel alloy metals and amorphous metals. Alternatively, the face component60is manufactured through casting, forming, machining, powdered metal forming, metal-injection-molding, electro chemical milling, and the like.

FIGS. 19-23illustrate the face component60in isolation. The face component60generally includes a striking plate portion (also referred to herein as a face plate)72and a return portion74extending laterally inward from the perimeter of the striking plate portion72. The striking plate portion72typically has a plurality of scorelines75thereon.

In a preferred embodiment, the return portion74generally includes an upper lateral section76, a lower lateral section78, a heel lateral section80and a toe lateral section82. Thus, the return74preferably encircles the striking plate portion72a full 360 degrees. However, those skilled in the pertinent art will recognize that the return portion74may only encompass a partial section of the striking plate portion72, such as 270 degrees or 180 degrees, and may also be discontinuous.

The upper lateral section76extends inward, towards the aft-body61, a predetermined distance, d, to engage the crown62. In a preferred embodiment, the predetermined distance ranges from 0.2 inch to 1.0 inch, more preferably 0.40 inch to 0.75 inch, and most preferably 0.68 inch, as measured from the perimeter73of the striking plate portion72to the rearward edge of the upper lateral section76. In a preferred embodiment, the upper lateral section76has a general curvature from the heel end66to the toe section68. The upper lateral section76has a length from the perimeter73of the striking plate section72that is preferably a minimal length near the center of the striking plate section72, and increases toward the toe end68and the heel end66.

The perimeter73of the striking plate portion74is defined as the transition point where the face component60transitions from a plane substantially parallel to the striking plate portion72to a plane substantially perpendicular to the striking plate portion72. Alternatively, one method for determining the transition point is to take a plane parallel to the striking plate portion72and a plane perpendicular to the striking plate portion, and then take a plane at an angle of forty-five degrees to the parallel plane and the perpendicular plane. Where the forty-five degrees plane contacts the face component is the transition point thereby defining the perimeter of the striking plate portion72.

The present invention preferably has the face component60engage the crown portion62along a substantially horizontal plane. The crown62has a crown undercut portion62a, which is placed under the return portion74. Such an engagement enhances the flexibility of the striking plate portion72allowing for a greater coefficient of restitution. The crown portion62and the upper lateral section76are attached to each other as further explained below.

The heel lateral section80is substantially perpendicular to the striking plate portion72, and the heel lateral section80covers the hosel54before engaging an optional ribbon section90and a bottom section91of the sole portion64of the aft-body61. The heel lateral section80is attached to the sole64, both the ribbon90and the bottom section91, as explained in greater detail below. The heel lateral section80extends inward a distance, d′″, from the perimeter73a distance of 0.250 inch to 1.50 inches, more preferably 0.50 inch to 1.0 inch, and most preferably 0.950 inch. The heel lateral section80preferably has a general curvature at its edge.

At the other end of the face component60is the toe lateral section82. The toe lateral section82is attached to the sole64, both the ribbon90and the bottom section91, as explained in greater detail below. The toe lateral section82extends inward a distance, d″, from the perimeter73a distance of 0.250 inch to 1.50 inches, more preferably 0.75 inch to 1.30 inch, and most preferably 1.20 inch. The toe lateral section80preferably has a general curvature at its edge.

The lower lateral section78extends inward, toward the aft-body61, a distance, d′, to engage the sole64. In a preferred embodiment, the distance d′ ranges from 0.2 inch to 1.25 inches, more preferably 0.50 inch to 1.10 inch, and most preferably 0.9 inch, as measured from the perimeter73of the striking plate portion72to the edge of the lower lateral section78.

The sole portion64has a sole undercut64afor placement under the return portion74. The sole64and the lower lateral section78, the heel lateral section80and the toe lateral section82are attached to each other as explained in greater detail below.

The aft-body61is preferably composed of an upper section200and a lower section202, which are joined together to form the aft-body61. The aft-body61is preferably composed of a low density material, preferably a metal or a polymer material. Preferably metals include magnesium alloys, aluminum alloys, magnesium or aluminum material. Exemplary magnesium alloys are available from Phillips Plastics Corporation under the brands AZ-91-D (nominal composition of magnesium with aluminum, zinc and manganese), AM-60-B (nominal composition of magnesium with aluminum and manganese) and AM-50-A (nominal composition of magnesium with aluminum and manganese). The aft-body61is preferably manufactured through metal-injection-molding, casting, forming, machining, powdered metal forming, electro chemical milling, and the like. Alternatively, the aft-body is composed of a polymer material such as plies of prepreg material, thermoplastic materials such as polyurethanes, polyesters, polyamides, ionomers, and other similar materials.

The face component60is preferably adhered to the aft-body61with an adhesive, which is preferably placed on the interior surface of the return portion74. The adhesive may also be placed on the undercut portions62aand64a. The upper section200is preferably adhered to the lower section202with an adhesive. Such adhesives include thermosetting adhesives in a liquid or a film medium. A preferred adhesive is a two part liquid epoxy sold by 3M of Minneapolis Minnesota under the brand names DP420NS and DP460NS. Other alternative adhesives include modified acrylic liquid adhesives such as DP810NS, also sold by the 3M company. Alternatively, foam tapes such as Hysol Synspan may be utilized with the present invention.

The gasket300is preferably composed of a polymer material. One such material is a thermoplastic polyurethane elastomer. The gasket300is preferably a single continuous piece. However, those skilled in the pertinent art will recognize that the gasket300may be composed of multiple pieces that are positioned within the annular gap170. The gasket300preferably has a thickness, “T”, ranging from 0.020 inch to 0.100 inch, more preferably from 0.040 inch to 0.080 inch, and most preferably 0.060 inch. The gasket300preferably “encircles” the entire golf club head42. The gasket300is preferably placed within the annular gap170. The annular gap170is located rearward from the striking plate portion72, and preferably ranges from 0.10 inch to 3.0 inches from the perimeter73of the striking plate portion72depending on the length of the golf club head42. Preferably, the annular gap170is positioned along the front half of the golf club head42, however, those skilled in the pertinent art will recognize that the annular gap may be positioned along the rear half of the golf club head42.

As shown inFIG. 13, the gasket300preferably has a width, “W1”, that ranges from 0.010 inch to 0.200 inch, more preferably from 0.040 to 0.120 inch, most preferably 0.075 inches. In the preferred embodiment shown inFIG. 28, the gasket has an “L” shaped cross section with the “OML” surface width with that ranges from 0.010 inch to 0.190 inch, more preferably from 0.030 inch to 0.100 inch, most preferably from 0.040 inch to 0.080 inch and a lip that ranges from 0.010 inch to 0.150 inch, more preferably from 0.040 inch to 0.120 inch, and most preferably 0.080 inch. In an alternative embodiment as shown byFIG. 29, the gasket can have a wedge shaped cross section with an the “OML” surface width with that ranges from 0.010 inch to 0.190 inch, more preferably from 0.030 inch to 0.100 inch, most preferably from 0.040 inch to 0.080 inch and a bottom width that ranges from 0.010 inch to 0.100 inch, more preferably from 0.020 inch to 0.070 inch, and most preferably 0.020 inch. In additional alternative embodiments the cross section may have square, rectangular, round, circular, or any other plurality of geometric cross sections of differing widths, as shown inFIGS. 13A-E.

The gasket300is preferably attached to the crown undercut portion62aand the sole undercut portion64aprior to attaching the face component60to the aft-body61. The gasket300is preferably attached to the crown undercut portion62aand the sole undercut portion64ausing an adhesive such as described above.

As shown inFIGS. 24 and 25, the return portion74overlaps the undercut portions62aand64aa distance ranging from 0.25 inch to 1.00 inch, more preferably ranges from 0.40 inch to 0.70 inch, and is most preferably 0.50 inch. An annular gap170is created between an edge190of the crown portion62and the sole portion64, and an edge195of the return portion74. The annular gap170preferably has a distance from the edge190of the crown portion62to the edge195of the return portion74ranging from 0.020 inch to 0.100 inch, more preferably from 0.050 inch to 0.070 inch, and is most preferably 0.060 inch. A plurality of projections177on an upper surface of the undercut portions62aand64aestablishes a minimum bond thickness between the interior surface of the return portion74and the upper surface of the undercut portions62aand64a. The bond thickness preferably ranges from 0.002 inch to 0.100 inch, more preferably ranges from 0.005 inch to 0.040 inch, and is most preferably 0.030 inch. A liquid adhesive preferably secures the aft body61to the face component60. A leading edge of the undercut portions62aand64amay be sealed to prevent the liquid adhesive from entering the hollow interior46.

FIGS. 14-16illustrate a preferred embodiment of the lower section202of the aft-body61. The sole portion64, including the bottom section91and the optional ribbon90which is substantially perpendicular to the bottom section91, preferably has a thickness in the range of 0.010 to 0.100 inch, more preferably in the range of 0.025 inch to 0.070 inch, even more preferably in the range of 0.028 inch to 0.040 inch, and most preferably has a thickness of 0.033 inch. The undercut portion64ahas a similar thickness to the sole portion64. The lower section202preferably comprises the bottom section91and a lower portion of the ribbon90. The bottom section91preferably has a medial ridge220which extends from the undercut portion64arearward. A heel convex portion222is preferably located on a heel end66next to the medial ridge220and a toe convex portion224is preferably located on a toe end68next to the medial ridge220. An alternative embodiment of the bottom section91is disclosed in U.S. Pat. No. 5,480,152, entitled Hollow, Metallic Golf Club Head With Relieved Sole And Dendritic Structures, assigned to Callaway Golf Company, and which pertinent parts are hereby incorporated by reference.

An aft weight cavity244is preferably located rearward of the medial ridge220. The aft weight cavity244preferably allows swing weighting of the golf club head42. The aft-weight cavity244is accessible from the exterior of the golf club head42was all of the components are joined together. The interior of lower section202has a heel weight cavity240and a rear weight cavity242for placement of mass prior to the joining of components of the golf club head42. The interior surface220aof the medial ridge220creates a depression in the interior surface of the lower section202while the interior surfaces222aand224aof the heel convex portion222and toe convex portion224create projections in the interior surface of the lower section202. A wall245of the aft-weight cavity244projects inward from the interior surface of the lower section202. The lower section2020has a first ledge250and a section ledge252.

FIGS. 17-18illustrate the upper section200of the aft-body61. The upper section200preferably comprises the crown portion62and an upper section of the ribbon90. The crown portion62of the aft-body61is generally convex toward the sole64, and engages the ribbon90of sole64outside of the engagement with the face member60. The crown portion62preferably has a thickness in the range of 0.010 to 0.100 inch, more preferably in the range of 0.025 inch to 0.070 inch, even more preferably in the range of 0.028 inch to 0.040 inch, and most preferably has a thickness of 0.033 inch. The undercut portion62ahas a similar thickness to the crown portion62. The interior surface of the upper section200has a plurality of interior projections179the engage the first ledge250of the lower section202. The upper section200has a first ledge254that engages the second ledge252of the lower section202. As explained above, the upper section200and the lower section202are joined together preferably through use of an adhesive. An aft-body gap205is preferably created upon joining of the upper section200and the lower section202. The crown undercut portion62ahas a plurality of undercut projections177extending upward from an exterior surface.

FIGS. 24-25illustrate the hollow interior46of the club head42. The hosel54is disposed within the hollow interior46, and is located as a part of the face component60. The hosel54may be composed of a similar material to the face component60, and is preferably secured to the face component60through welding or the like. The hosel54may also be formed with the formation of the face component60. Additionally, the hosel may be composed of a non-similar material that is light weight and secured using bonding or other mechanical securing techniques. A hollow interior of the hosel54is defined by a hosel wall120that forms a tapering tube from the aperture59to the sole potion64. The shaft48is disposed within a hosel insert121that is disposed within the hosel54. Such a hosel insert121and hosel54are described in U.S. Pat. No. 6,352,482, entitled Golf Club With Hosel Liner, which pertinent parts are hereby incorporated by reference. Alternatively, to provide greater capability as to the control of the face angle of the golf club head42, an insert and hosel liner combination such as disclosed in U.S. Pat. No. 6,475,100 is utilized, and U.S. Pat. No. 6,475,100 is hereby incorporated by reference in its entirety.

As shown inFIG. 23, weighting members122a,122band122care preferably disposed within the heel weight cavity240, the rear weight cavity242and the aft-weight cavity244, respectively. In a preferred embodiment, all of the weighting members122a,122band122care utilized in order to increase the moment of inertia and control the center of gravity of the golf club head42. However, those skilled in the pertinent art will recognize that none or only one or two of the weighting members122a,122band122c, and also additional weighting members may be placed in locations of the club head42in order to influence the center of gravity, moment of inertia, or other inherent properties of the golf club head42. A preferred use of weighting members to influence the center of gravity of the a golf club head is disclosed in co-pending U.S. patent application Ser. No. 10/249,510, filed on Apr. 15, 2003, for a Golf Club Head With Customizable Center Of Gravity, and assigned to Callaway Golf Company, which is hereby incorporated by reference in its entirety.

In a preferred embodiment, the weighting members122a,122band122care bonded within the heel weight cavity240, the rear weight cavity242and the aft-weight cavity244, respectively. Individually, each of the weighting members122a,122band122chas a mass ranging from 10 grams to 30 grams, preferably from 14 grams to 25 grams, and more preferably from 15 grams to 20 grams. Each of the weighting members122a,122band122chas a density ranging from 5 grams per cubic centimeters to 20 grams per cubic centimeters, more preferably from 7 grams per cubic centimeters to 12 grams per cubic centimeters, and most preferably 8.0 grams per cubic centimeters.

The metal material of each of the weighting members122a,122band122cis preferably selected from copper, tungsten, steel, aluminum, tin, silver, gold, platinum, or the like. A preferred metal is tungsten due to its high density. The polymer material of each of the weighting members122a,122band122cis preferably a thermoplastic or thermosetting polymer material. A preferred polymer material is polyurethane, epoxy, nylon, polyester, or similar materials. A most preferred polymer material is a thermoplastic polyurethane. The weighting members122a,122band122care preferably composed an injection molded thermoplastic polyurethane integrated with tungsten to have a density of 8.0 grams per cubic centimeters. In a preferred embodiment, each of the weighting members122a,122band122care composed of from 50 to 95 volume percent polyurethane and from 50 to 5 volume percent tungsten. Also, in a preferred embodiment, each of the weighting members122a,122band122care composed of from 10 to 25 weight percent polyurethane and from 90 to 75 weight percent tungsten. Those skilled in the pertinent art will recognize that other high density materials may be utilized as an optional weighting member without departing from the scope and spirit of the present invention. Alternatively, the ribbon section90may have a thickened region to provide mass for the aft-body61.

FIG. 13illustrates a preferred embodiment of the face component of the golf club head42.FIG. 13illustrates the variation in the thickness of the striking plate portion72. The striking plate portion72is preferably partitioned into elliptical regions, each having a different thickness. In a preferred embodiment in which the face component60is composed of a titanium or titanium alloy material, a central elliptical region102preferably has the greatest thickness that ranges from 0.120 inch to 0.090 inch, preferably from 0.115 inch to 0.100 inch, and is most preferably 0.105 inch. The central elliptical region102preferably has a uniform thickness. A first concentric region104preferably has the next greatest thickness that ranges from 0.110 inch to 0.076 inch, preferably from 0.100 inch to 0.086 inch, and is most preferably 0.088 inch. The first concentric region preferably has a thickness that transitions from the first concentric region102thickness to the periphery region110thickness. A periphery region110preferably has the next greatest thickness that ranges from 0.082 inch to 0.062 inch, and is most preferably 0.072 inch. The variation in the thickness of the striking plate portion72allows for the greatest thickness to be localized in the center111of the striking plate portion72thereby maintaining the flexibility of the striking plate portion72which corresponds to less energy loss to a golf ball and a greater coefficient of restitution without reducing the durability of the striking plate portion72.

Other alternative embodiments of the thickness of the striking plate portion72are disclosed in U.S. Pat. No. 6,471,603, for a Contoured Golf Club Face and U.S. Pat. No. 6,398,666 for a Golf Club Striking Plate With Variable Thickness, which are both owned by Callaway Golf Company and which pertinent parts are hereby incorporated by reference.

As mentioned previously, the face component60is preferably forged from a rod of metal material. One preferred forging process for manufacturing the face component is set forth in U.S. Pat. No. 6,440,011, entitled Method For Processing A Striking Plate For A Golf Club Head, owned by Callaway Golf Company, and hereby incorporated by reference in its entirety. Alternatively, the face component60is cast from molten metal in a method such as the well-known lost-wax casting method. Additional methods for manufacturing the face component60include forming the face component60from a flat sheet of metal, super-plastic forming the face component60from a flat sheet of metal, machining the face component60from a solid block of metal, electrochemical milling the face from a forged pre-form, and like manufacturing methods. Yet further methods include diffusion bonding titanium sheets to yield a variable face thickness face and then superplastic forming.

Alternatively, the face component60is composed of an amorphous metal material such as disclosed in U.S. Pat. No. 6,471,604, owned by Callaway Golf Company, and which pertinent parts are hereby incorporated by reference in its entirety.

The present invention is directed at a golf club head that has a high coefficient of restitution thereby enabling for greater distance of a golf ball hit with the golf club head of the present invention. The coefficient of restitution (also referred to herein as “COR”) is determined by the following equation:

e=v2-v1U1-U2
wherein u1is the club head velocity prior to impact; U2is the golf ball velocity prior to impact which is zero; v1is the club head velocity just after separation of the golf ball from the face of the club head; v2is the golf ball velocity just after separation of the golf ball from the face of the club head; and e is the coefficient of restitution between the golf ball and the club face.

The values of e are limited between zero and 1.0 for systems with no energy addition. The coefficient of restitution, e, for a material such as a soft clay or putty would be near zero, while for a perfectly elastic material, where no energy is lost as a result of deformation, the value of e would be 1.0. The present invention provides a club head having a coefficient of restitution ranging from 0.81 to 0.94, as measured under conventional test conditions.

The coefficient of restitution of the club head42under standard USGA test conditions with a given ball preferably ranges from approximately 0.81 to 0.94, preferably ranges from 0.83 to 0.883 and is most preferably 0.87.

Additionally, the striking plate portion72of the face component60has a smaller aspect ratio than face plates of the prior art. The aspect ratio as used herein is defined as the width, “W”, of the face divided by the height, “H”, of the face, as shown inFIG. 1A. In one preferred embodiment, the width W is 78 millimeters and the height H is 48 millimeters giving an aspect ratio of 1.625. In conventional golf club heads, the aspect ratio is usually much greater than 1. For example, the original GREAT BIG BERTHA® driver had an aspect ratio of 1.9. The striking plate portion72of the present invention has an aspect ratio that is no greater than 1.7. The aspect ratio of the present invention preferably ranges from 1.0 to 1.7. One embodiment has an aspect ratio of 1.3. The striking plate portion72of the present invention is more circular than faces of the prior art. The face area of the striking plate portion72preferably ranges from 4.00 square inches to 7.50 square inches, more preferably from 5.00 square inches to 6.5 square inches, and most preferably from 5.8 square inches to 6.0 square inches.

The club head42preferably has a greater volume than a club head of the prior art while maintaining a weight that is substantially equivalent to that of the prior art. The volume of the club head42of the present invention ranges from 290 cubic centimeters to 600 cubic centimeters, and more preferably ranges from 330 cubic centimeters to 510 cubic centimeters, even preferably 350 cubic centimeters to 465 cubic centimeters, and most preferably 385 cubic centimeters or 415 cubic centimeters.

The mass of the club head42preferably ranges from 165 grams to 225 grams, preferably ranges from 175 grams to 205 grams, and most preferably from 190 grams to 200 grams. Preferably, the face component60has a mass ranging from 50 grams to 110 grams, more preferably ranging from 65 grams to 95 grams, yet more preferably from 70 grams to 90 grams, and most preferably 78 grams. The aft-body61(without weighting) has a mass preferably ranging from 10 grams to 60 grams, more preferably from 15 grams to 50 grams, and most preferably 35 grams to 40 grams. The weighting members122a,122band122chave a combined mass preferably ranging from 30 grams to 120 grams, more preferably from 50 grams to 80 grams, and most preferably 60 grams. The interior hosel54preferably a mass preferably ranging from 3 grams to 20 grams, more preferably from 5 grams to 15 grams, and most preferably 12 grams. Additionally, epoxy, or other like flowable materials, in an amount ranging from 0.5 grams to 5 grams, may be injected into the hollow interior46of the golf club head42for selective weighting thereof.

As shown inFIG. 5, the length, “Lg”, of the club head42from the striking plate portion72to the rear section of the crown portion62preferably ranges from 3.0 inches to 4.5 inches, and is most preferably 3.5 inches. As shown inFIG. 12, the height, “Hg”, of the club head42, as measured while in striking position, preferably ranges from 2.0 inches to 3.5 inches, and is most preferably 2.50 inches. As shown inFIG. 5, the width, “Wg”, of the club head42from the toe section68to the heel section66preferably ranges from 4.0 inches to 5.0 inches, and more preferably 4.4 inches.

FIGS. 9 and 10illustrate the axes of inertia through the center of gravity of the golf club head. The axes of inertia are designated X, Y and Z. The X axis extends from the striking plate portion72through the center of gravity, CG, and to the rear of the golf club head42. The Y axis extends from the toe section68of the golf club head42through the center of gravity, CG, and to the heel section66of the golf club head42. The Z axis extends from the crown portion62through the center of gravity, CG, and to the sole portion64.

As defined inGolf Club Design, Fitting, Alteration&Repair,4thEdition, by Ralph Maltby, the center of gravity, or center of mass, of the golf club head is a point inside of the club head determined by the vertical intersection of two or more points where the club head balances when suspended. A more thorough explanation of this definition of the center of gravity is provided inGolf Club Design, Fitting, Alteration&Repair.

The center of gravity of a golf club head may be obtained using a center of gravity table having two weight scales thereon, as disclosed in U.S. Pat. No. 6,607,452, entitled High Moment Of Inertia Composite Golf Club, owned by Callaway Golf Company, and hereby incorporated by reference in its entirety. If a shaft is present, it is removed and replaced with a hosel cube that has a multitude of faces normal to the axes of the golf club head. Given the weight of the golf club head, the scales allow one to determine the weight distribution of the golf club head when the golf club head is placed on both scales simultaneously and weighed along a particular direction, the X, Y or Z direction.

In general, the moment of inertia, lzz, about the Z axis for the golf club head42preferably ranges from 2800 g-cm2to 5000 g-cm2, preferably from 3000 g-cm2to 4500 g-cm2, and most preferably from 3750 g-cm2to 4250 g-cm2. The moment of inertia, lyy, about the Y axis for the golf club head42preferably ranges from 1500 g-cm2to 2750 g-cm2, preferably from 2000 g-cm2to 2400 g-cm2, and most preferably from 2100 g-cm2to 2300 g-cm2. The moment of inertia, lxx, about the X axis for the golf club head42preferably ranges from 1500 g-cm2to 4000 g-cm2, preferably from 2000 g-cm2to 3500 g-cm2, and most preferably from 2500 g-cm2to 3000 g-cm2.

In general, the golf club head42has products of inertia such as disclosed in U.S. Pat. No. 6,425,832, and is hereby incorporated by reference in its entirety. Preferably, each of the products of inertia, lxy, lxz and lyz, of the golf club head42have an absolute value less than 100 grams-centimeter squared. Alternatively, the golf club head42has a at least one or two products of inertia, Ixy, lxz and lyz, with an absolute value less than 100 grams-centimeter squared.

The gasket (300) may be utilized with a golf club head such as described in U.S. Pat. No. 6,582,323, for a Multiple Material Golf Club Head, which is hereby incorporated by reference in its entirety.