Weighted golf club head

A golf club head having a center of gravity located at a point close to the face and the sole is disclosed herein. In particular, the golf club head comprises a hollow body including a weight lip and face component, and the weight lip extends from the sole inside the body towards the face component without making contact with the face component. The golf club head is preferably an iron-type golf club head. In other embodiments, the golf club head, which may be an iron-type golf club head, comprises a weight bar disposed within the hollow body proximate the face component, and the weight bar bridges at least a portion of the sole. The weight bar may be movable within the hollow body to allow for center of gravity adjustment.

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a golf club head having internal weighting that locates the center of gravity of the golf club head close to the face and sole.

2. Description of the Related Art

Golfers often prefer to use golf clubs having low centers of gravity that are also close to the face, which allows for greater control over golf balls during play. There is a need for golf club heads having improved internal weighting.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention is an iron-type golf club head comprising a body comprising a top line, a sole, a heel side, a toe side, a frontal opening, and a protrusion, and a face component comprising a striking face covering the frontal opening, wherein the protrusion is located proximate the frontal opening and extends towards the face component without touching any portion of the striking face, and wherein the protrusion extends from the heel side to the toe side and does not comprise any hollow regions. In some embodiments, the protrusion may extend through the frontal opening. In other embodiments, the face component may be a face cup that comprises an upper flange and a lower flange, and each of the upper flange and lower flange may extend rearwards away from the striking face. In a further embodiment, the upper flange may comprise a first length, the lower flange may comprise a second length, and the first length may be less than the second length. In a further embodiment, the second length may be between 5 mm and 10 mm. In another embodiment, the lower flange may comprise variable thickness.

In another embodiment, the face component may be welded to the body to form a weld line, wherein the protrusion may extend over the weld line. In some embodiments, the frontal opening may extend completely through the body so that the body comprises a rear opening, and in a further embodiment, the iron-type golf club head may comprise a back cap, which may be disposed over the rear opening. In other embodiments, the protrusion may comprise an upper surface and a front surface, and the upper surface may be disposed approximately perpendicular to the front surface. In some embodiments, the protrusion may be integrally cast with the body.

Another aspect of the present invention is an iron-type golf club head comprising a face cup comprising a striking face, an upper flange, and a lower flange, and a body comprising a top line, a sole, a heel side, a toe side, a frontal opening, and a protrusion, wherein the frontal opening extends completely throughout the body to form a rear opening, wherein the upper flange comprises a first length, wherein the lower flange comprises a second length that is longer than the first length, wherein the striking face comprises variable thickness, and wherein the protrusion is located proximate the frontal opening and extends through the frontal opening towards the face component without touching any portion of the face cup. In some embodiments, the protrusion may bridge at least a portion of the sole, and in a further embodiment, the iron-type golf club head may comprise a plurality of pins, each of which may be disposed between the sole and the protrusion.

In some embodiments, the protrusion may be composed of a plurality of materials. In a further embodiment, at least one of the plurality of materials may be a tungsten alloy. In other embodiments, the face cup may be welded to the body to form a weld seam, which may have a constant thickness. In another embodiment, the iron-type golf club head may further comprise a back cap, which may be affixed to the body and may cover the rear opening. In other embodiments, the protrusion may comprise an upper weight portion and a lower support portion, the upper weight portion may be composed of a first material having a first density, the lower support portion may be composed of a second material having a second density, and the first density may be greater than the second density.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is generally directed to a golf club head having internal weighting that places the golf club center of gravity (CG) at a point near both the face and the sole of the golf club head. In particular, the present invention is directed to integrally formed weighting in smaller golf club heads, particularly fairway woods, hybrids, and irons.

A first embodiment of the present invention is shown inFIGS. 1-3. The golf club head10, which in the first embodiment is a fairway wood head, includes a body20having a sole30, a crown40, a hosel50, a cavity22, and a weight lip80, and a face component60comprising a striking face62, a return portion64, and a cavity66. The striking face62preferably has a high characteristic time (CT). The face component60preferably is integrally forged from a metal alloy such as 6-4 titanium or stainless steel, while the body20preferably is integrally cast from such alloys. In other embodiments, the face component60and body20may be constructed using different methods and with any materials commonly used for golf club manufacturing. In some embodiments, the face component60and body20may be integrally formed. The body20may further comprise another weighting element, such as a weight pad, a thickened wall area, or a removable weight screw (not shown) to allow a manufacturer or a golfer to adjust any remaining discretionary weight.

Once the body20and face component60are formed, they are welded together along the opening25at the front of the body20. The weld seam70, shown inFIG. 3, has a constant, relatively low thickness, preferably approximately 0.031 inch. In order to achieve a low, frontward CG without affecting the weld seam70, the weight lip80is located inside the cavity22and proximate the opening25. This construction avoids creating welding problems, but still allows for discretionary mass to be located mostly low and forward in the golf club head.

The weight lip80, which preferably is cast into the body20but may, in alternative embodiments, be welded or affixed mechanically to the body20, extends upwards from the sole30and protrudes from the opening25of the body20. When the golf club head10is assembled, the weight lip80extends into the cavity66of the face component60without making contact with the striking face62. The weight lip80preferably comprises at least 20% of the mass of the body20, and more preferably 30% of the mass of the body. For example, the golf club head10may have the weight distribution shown in Table I.

In another embodiment, shown inFIGS. 4 and 5A, a groove82extends underneath the upper weighted portion84of the weight lip80, creating an overhang construction which reduces the weight of the weight lip80, and thus the overall weight of the golf club head10, while still maintaining sufficient weight near the face component60to maintain a low, forward CG. In a further embodiment, shown inFIG. 5B, the weight lip80is constructed of multiple materials, with the upper weighted portion84composed of a higher density material than the rest of the weight lip80. In particular, the lower support portion86of the weight lip80is composed of a stainless steel material, while the upper weighted portion84is composed of a tungsten alloy and welded or otherwise affixed to the lower support portion86of the weight lip80. In this embodiment, the groove82preferably extends slightly further away from the face component60and into the lower support portion86in order to better counteract the additional weight provided by the higher density upper weighted portion84.

As shown inFIGS. 6,7A, and7B, in another embodiment the weight lip80includes a larger, squarer upper weighted portion84and a narrower lower support portion86, with the groove82extending inwards away from the face component60and upwards towards the crown40, such that the groove82has a hook-like configuration. As with the embodiment shown inFIG. 5B, in the embodiment shown inFIG. 7B, the upper weighted portion84is a separate piece formed of a high density material such as tungsten alloy, which can be welded, glued, or otherwise affixed to the lower support portion86. This allows for greater customization of the golf club head10during manufacture, as mass properties such as CG and moment of inertia can be tailored to the end user by adjusting the material properties of the weight lip80.

In another embodiment of the present invention, shown inFIGS. 8 and 9, the body20of the golf club head10includes a weight bar90, which is affixed within the interior of the body20only at a heel side24and toe side26of the golf club head10, effectively bridging the entire sole30. This structure allows for activation of the face component60and the sole30without having an excessive effect on mass properties, as the weight bar90acts as a torsion spring during impact of the golf club head10with a ball. In some embodiments, the weight bar90is integrally cast with the crown40and the heel and toe sides24,26, and the sole30is affixed after the casting is complete, though in alternative embodiments the weight bar90may be separately constructed and then affixed within the body20at the heel and toe sides24,26via mechanical fasteners, epoxy, welding, brazing, or any other methods known to a person skilled in the art.

In the embodiment shown inFIG. 10, the weight bar90is movably affixed to the heel and toe sides24,26with a pin100or other moving element, and the weight bar90has a polygonal shape and is affixed to the pin100at one edge95, such that rotating the pin100anywhere from 1 to 359 degrees moves the majority of the mass of the weight bar90to different locations within the body20, thus adjusting the location of the golf club head's10CG. Different weight bar90and pin100combinations are shown inFIGS. 11A-F, and may include one or more cross-sectional shapes and/or high-density portions or inserts105. Once the desired CG location is achieved, the pin100, and thus the weight bar90, can be temporarily fixed in place by any means known to a person of ordinary skill in the art, including mechanical fasteners and/or removable adhesives, or permanently fixed in place via techniques such as welding, brazing, and/or the use of permanent adhesives.

In an alternative embodiment, shown inFIGS. 12-14, the weight bar90is affixed to the sole30at only two places, one near the heel side24of the body20and one near the toe side26of the body, effectively bridging most of the sole30. In this and the embodiments shown inFIGS. 9-10, the weight bar90may have any cross-sectional shape, including the triangular weight bar90structure shown inFIG. 10, the quadrilateral weight bar90structure shown inFIG. 14, and the trapezoidal weight bar90structure shown inFIG. 16. Portions of the weight bar90may be made from different materials to further customize the golf club head10and adjust the CG location.

As shown in the Figures, the face component60of the present invention may take different forms and structures to maximize the striking area of the striking face62, optimize return in small volume golf clubs like fairway woods, irons, and hybrids, and increase performance characteristics such as characteristic time (CT) and coefficient of resistance (COR). In particular, the face component60may include a return portion64that fully or mostly encircles the striking face62, forming a face cup, or the return portion64may only extend from a portion of the striking face62, e.g., from the toe, heel, crown, and/or sole edges61,63,65,67of the striking face62. For example, the face component60shown inFIGS. 1,4,6,8, and12has a return portion64that extends from the toe, crown, and sole edges61,65,67of the striking face62but not from the heel edge63, forming a partial face cup. In the embodiment shown inFIG. 24, the face component60may include nothing but the striking face62, with no return portion64.

As shown inFIGS. 15 and 16, in another embodiment the face component60has an “r” shaped configuration, with a return portion64extending from the crown side of the striking face62but nowhere else. In this way, the weld seam70is moved away from the striking face62at the crown junction110, but remains at the sole, toe, and heel junctions112,114,116of the striking face62, which reduces stress at the crown junction while still maintaining high COR and CT values. The weld seam70also may be non-planar.

In other embodiments, the golf club head10may include an additional weight structure. For example, the embodiment shown inFIGS. 17-22includes a weight bar90extending from the heel side24of the sole30to the toe side26of the sole30, a face component60having return portions64extending from the crown, sole, and toe edges65,67,61, and an internal weight band120extending along most of the junction between the sole30and the crown40inside the cavity22of the golf club head10. This construction allows the club to have both a desired mass and thin sole30and crown40portions, thus increasing the compliance of the striking face62and optimizing CG.

For each of the weight bar90embodiments disclosed herein, the weight bar90may be supported with one or more pins92, shown inFIGS. 23A and 23B, which are affixed to the sole30within the cavity22of the golf club head10and connect with a bottom surface94of the weight bar90and/or a rear surface (not shown) of the weight bar90. The pins preferably are separate pieces composed of a strong, lightweight material such as plastic or composite so that their presence does not detract from the mass configuration created by the weight bar90, but in some embodiments may be integrally formed with the sole30and the weight bar90itself.

For all embodiments disclosed herein, the face component60preferably is composed of a high-strength, high performance material to minimize the detrimental influence of weld location on performance. The face component60preferably is constructed so that the striking face62has a maximum CT of 235-260 at its geometric center68, and a CT of 205-260 at all points located approximately 0.25 inch from the geometric center, and at least at the high center and low center points on the striking face62.

Each of the embodiments of the weight lip80and weight bar90disclosed herein may be incorporated into the four piece, multi-material golf club head200structure shown inFIG. 24to better configure mass properties and performance characteristics such as CT and COR. This structure can be used with wood-type and hybrid-type golf club heads. In one embodiment of this golf club head200, the golf club head200includes a body220formed of a material having a lower density than steel, the material being both castable and weldable, the body220having a crown opening222, a sole opening224, and a face opening226. A sole230composed of a steel material, or a denser material than steel, is then welded or brazed to the body220, closing off the sole opening224. A lightweight crown240composed of low-density carbon or a thin, strong, lightweight metal is then affixed to the body220, closing the crown opening222, and a face plate260composed of a high strength material is welded or brazed to the body220, closing the face opening226. This multi-material embodiment contributes to optimized center of gravity location, which is particularly useful in fairway woods. The face opening226and face plate260preferably include joint locations that are optimized for minimum interference with the striking surface and flexing regions of the body220.

In another embodiment, the golf club head200shown inFIG. 24has a material composition that contributes to optimized moment of inertia values, which is particularly useful in hybrids. In this embodiment, the body220is composed of a material having a higher density than steel, the material being both castable and weldable, the sole230is composed of a steel material or a denser material and is welded or brazed to the body220, the crown is240is composed of a low-density carbon material and is bonded to the body220, and the face plate260is composed of a high strength material and is welded or brazed to the body.

The weight bar90configurations disclosed with the embodiments herein can also be used with an iron-type golf club head as shown inFIGS. 25-28. In this embodiment of the present invention, the iron-type golf club head300comprises a body305having a top line310, a sole320, a toe side330, a heel side340, and a rear cavity380, a face component350, and a weight bar360. The weight bar360bridges the sole320, forming a narrow slot370between the weight bar360and the sole320and providing room for the face component350to deflect downward when the golf club head300makes contact with a ball. One or more pins92, examples of which are shown inFIGS. 23A and 23B, can be disposed within the slot, between the weight bar360and the sole320, to provide additional support to the weight bar360. In alternative embodiments, the weight bar360may be rotatable within the rear cavity380as disclosed in connection with other embodiments herein, and the golf club head300may be made of multiple materials, such as different types of steel. The weight bar360may be composed of multiple materials in order to affect mass properties of the golf club head300, and may have any cross-sectional shape, including the ones disclosed in connection with other embodiments of the present invention.

In one embodiment, the face component350is a face insert, but in other embodiments it may be a face plate or a face cup. As shown inFIGS. 25-28, the face component350(and any other face components disclosed herein) preferably has a striking surface with a variable thickness pattern, which may be any pattern disclosed in U.S. Pat. Nos. 7,137,907, 7,101,289, 7,258,626, 7,422,528, 7,448,960, 7,713,140, 8,012,041, and 8,376,876, the disclosure of each of which is hereby incorporated by reference in its entirety herein, and U.S. Patent Publication Number 20120021849, the disclosure of which is also hereby incorporated by reference in its entirety herein.

Similarly, the weight lip80configurations disclosed herein with respect to wood and hybrid type golf club heads may also be used with iron-type golf club heads, as illustrated by the preferred embodiment shown inFIGS. 29-32. In the preferred embodiment, the iron-type golf club head400comprises a body410and a face cup420that are welded together to form a weld seam430, which preferably has a constant thickness.

The body410, which preferably is integrally cast from a steel material, comprises a top line411, a sole412, a hosel413, a toe end414, a heel end415, a rear wall416, and a front opening418that extends completely through the body410such that the body410has an open back, and also includes a weight lip440. The weight lip440preferably is integrally cast with the body410, but may in alternative embodiments be affixed to the body410after both pieces are independently created. The weight lip440of the preferred embodiment extends from the sole412and the rear wall416of the body410towards the front opening418, and also extends from the heel end415towards the toe end414of the body410. In some embodiments, the weight lip440may contact both the toe and heel ends414,415, but in the preferred embodiment, as shown inFIG. 30, the weight lip440only makes contact with the heel end415proximate the hosel413.

As shown inFIG. 32, the face cup420comprises a striking face422, an upper flange424, and a lower flange426, which has a length L1that is longer than the length L2of the upper flange424. Length L1preferably is between 5 and 10 mm, and more preferably is 6 to 9 mm. The lower flange426preferably has variable thickness, which improves the performance of the golf club head400. The face cup420also comprises a toe-side flange428, as shown inFIG. 30, but no flange along its heel side, where the face cup420is welded directly to the heel end415of the body410proximate the hosel413.

As with the embodiment shown inFIG. 3, at least a portion of the weight lip440protrudes through the front opening418, such that when the body410is assembled with the face cup420, the weight lip440extends over the weld seam430and approaches, but does not make contact with, the rear surface423of the striking face422. The weight lip440in the preferred embodiment has an upper surface442that is approximately perpendicular to its forward surface444, but in alternative embodiments of the iron-type golf club head400of the present invention, shown inFIGS. 33-37, the weight lip440may have different dimensions and structures. In the embodiments shown inFIGS. 35-37, the open back of the body410is closed with a back cap450to create a hollow iron-type golf club head400. The back cap450may be composed of the same material as the body410and/or the face cup420, or may be composed of a lightweight material such as plastic or composite.

In an alternative embodiment, shown inFIG. 38, a separate, lightweight material460such as plastic, composite, or rubber is added to the forward surface444of the weight lip440to connect the weight lip440to the striking face422(or any other part of the face cup420). This feature helps modulate the sound of the golf club head400during use. In this embodiment, the lightweight material460preferably is disposed approximately 0.075 inch vertically from the lower flange426, and is spaced at least 0.5 inches from the center of the rear surface423of the striking face422.

In each of the embodiments disclosed herein, the inertia of the weight lip80,440or weight bar90,360during impact of the golf club head10with a ball improves sole30compliance by enhancing the bending capabilities of thinner regions of the sole30. The weight construction shown in these Figures also allows the face component60to have a face cup (a return portion64extending part or completely around the periphery of the striking face62) construction without sacrificing an optimized center of gravity location, and also allows the manufacturer of the club head10to take weight away from, and thus thin out, the sole30, which allows the sole30to flex and bend more easily and thus contribute more to performance of the face component60.