Golf Club Head With Sole Compliance Zone

The present application a continuation application of U.S. patent application Ser. No. 18/388,621, filed on Nov. 10, 2023, which is a continuation application of U.S. patent application Ser. No. 17/935,547, filed on Sep. 26, 2022, now U.S. Pat. No. 11,813,504, issued on Nov. 14, 2023, which claims priority to U.S. Provisional Patent Application No. 63/249,418, filed on Sep. 28, 2021, now expired, the disclosure of each is hereby incorporated in its entirety herein.

Not Applicable

The present invention relates to a hollow golf club head, and particularly a fairway wood-type golf club head, with a compliance zone in the sole that optimizes deflection of the face during impact with a golf ball.

Many golfers have a swing that does not easily allow for a descending attack angle as their golf club head approaches a golf ball. This does not create a problem for tee shots, as the ball is elevated from the ground and there is plenty of room for the player to position the lower half of the club beneath the center of the golf ball prior to impact. However, for shots taken off of a tight lie, swings with a level or ascending attack angle tend to result in impact locations very low on the golf club face, which have much lower ball speeds and non-optimal backspin and launch angle compared with shots generated from face center impacts. This is especially problematic in fairway woods, where the relatively small amount of loft coupled with a low impact location results in an extremely low launch angle. The ball speed drop-off on fairway woods as hit location moves below the face center is also more severe than on drivers due to the overall size of the face and the increase in face stiffness closer to the face boundary. Therefore, there is a need for a golf club head, and in particular a fairway wood head, with an improved design that improves launch conditions for shots hit low on the face.

One aspect of the present invention is a golf club head with a sole compliance zone, an area in the sole proximate the face with a lower stiffness than prior art golf club heads so as to change the launch conditions (ball speed, launch angle, backspin) for shots low on the face.

Another aspect of the present invention is a golf club head comprising a body comprising a face portion with a face opening, a return section, a sole section, a heel side, a toe side, an aft end, and a hosel, a crown insert, a face cup sized to fit within the face opening, and at least one plug, wherein the sole section comprises a compliance zone located within three inches of the face portion measured along a front-to-back x-axis, wherein the compliance zone comprises a plurality of through-openings, and wherein each of the plurality of through-openings is filled with the at least one plug. In some embodiments, at least one of the plurality of through-openings may be circular. In other embodiments, the plurality of through-openings may comprise twenty through-openings. In a further embodiment, the at least one plug may comprise twenty plugs, and each of the twenty through-openings may be filled with one of the twenty plugs. In any of the embodiments, the golf club head may be a fairway wood-type golf club head.

In other embodiments, the at least one plug may be a secondary filler piece comprising a base portion and a plurality of extensions, each of the plurality of extensions may extend from the base portion, and each of the plurality of extensions may fill one of the plurality of through-openings. In a further embodiment, the secondary filler piece may comprise an inner portion and a cover piece, the inner piece may be composed of a high-density material, and the cover piece may be composed of a material having a lower density than the high-density material. In some embodiments, the inner portion may be metal injection molded and the cover piece may be overmolded over the inner portion. In other embodiments, the cover piece may comprise each of the plurality of extensions. In yet another embodiment, the body may further comprise a plurality of pegs extending from an interior surface of the sole portion within the compliance zone, each peg of the plurality of pegs may be disposed behind a through-opening of the plurality of through-openings, the base portion of the secondary filler piece may comprise a plurality of sockets, and each peg of the plurality of pegs may be sized to fit within a socket of the plurality of sockets.

In another embodiment, the plurality of through-openings may be disposed proximate to and is aligned parallel with the face opening. In another embodiment, the plurality of through-holes may vary in shape, size, and length across the compliance zone. In yet another embodiment, the compliance zone may comprise a variable thickness ranging from 0.01 inch to 0.05 inch. In still another embodiment, each of the face cup and the body may be composed of a metal material, and wherein the crown insert is composed of a non-metal material. In any embodiment, the face cup may be composed of a first metal material, the body may be composed of a second metal material, and the first metal material may be different from the second metal material.

Another aspect of the present invention is a fairway wood golf club head comprising a body comprising a face portion with a face opening, a crown section, a sole section, a heel side, a toe side, an aft end, and a hosel, a face component sized to fit within the face opening, and a filler piece comprising a base portion, a plurality of extensions, an inner portion composed of a first material, and a cover piece composed of a second material that has a lower density than the first material, wherein the sole section comprises a compliance zone located within three inches of the face portion measured along a front-to-back x-axis, wherein the compliance zone has a variable thickness ranging from 0.01 inch to 0.05 inch and comprises a plurality of through-openings, wherein each of the plurality of through-openings is filled with an extension of the plurality of extensions, and wherein the face component is selected from the group consisting of a face insert and a face cup.

In some embodiments, the plurality of through-openings may be disposed proximate to and be aligned parallel with the face opening. In other embodiments, the plurality of through-holes may vary in shape, size, and length across the compliance zone. In yet another embodiment, the cover piece may comprise each of the plurality of extensions.

Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

The present invention is directed to a golf club head, and particularly a hollow fairway wood head, with a sole compliance zone located proximate the face. The sole compliance zone is a low stiffness region that affects the magnitude of club head deflection upon impact with a golf ball and causes the face to deflect downwards during that impact, allowing the face to move upwards during recovery from initial deflection as the ball leaves the face. The head deflection mode shapes should occur at frequencies similar to the face mode, or 2000 to 7000 Hz, more preferably 3000 to 60000 Hz, and most preferably 4000 to 5000 Hz. This altered face motion imparts a higher launch angle and lower backspin to the golf ball than it would with prior art constructions.

A first embodiment of this invention is shown in. In this embodiment, the golf club headis a fairway wood with a bodywith a face openingin a front surface, a return section, a sole section, a heel side, a toe side, and an aft end, a face cup, a crown insert, and a hosel. The sole sectionincludes the compliance zone, which is located within three inches of the front surfacemeasured along the front to back x-axis and extends from a first locationwithin one inch of the heel sideto a second locationwithin one inch of the toe side. In other embodiments, the golf club headmay have a face insert instead of a face cup, and the crown portion may be integrally cast, forged, formed, etc. with the body so that there is no need for a separate crown insert. In still other embodiments, the striking facemay be integrally cast, forged, formed, etc. with the body so that there is no need for a separate face cupor face insert.

The compliance zoneof the first embodiment comprises a plurality of through-openingsfilled with plugscomposed of a low-density elastomeric material, such as rubber. The through-openingsare circular, but may have different shapes, such as those disclosed in U.S. Pat. No. 9,782,642, the disclosure of which is hereby incorporated by reference in its entirety herein. In the first embodiment, there are twenty-two through-openingsfilled with separate plugs.

In alternative embodiments, the plugsmay be connected by a thin membrane or other connective material such that there is a single, secondary filler piecethat serves to fill all of the through-openings. There may also be a different number of through-openingswith larger or smaller diameters and different shapes of varying size. These concepts are illustrated by the second, preferred embodiment shown in, the third embodiment shown in, and the fourth embodiment shown in.

As shown in, the fairway wood golf club headhas most of the same characteristics as the first embodiment, except that there are fewer through-openingsand these through-openingsare filled with a secondary filler piececomprising a base sectionand a plurality of extensionssized to fit within the through-openings. This filler pieceis composed of a high density, metal injection molded inner portionthat is then overmolded with a cover piecemade of a lower modulus material. The inner portionis metal injection molded to allow the manufacturer greater control over its shape and density, and the cover pieceis designed to be bonded to the inside of the sole. The multiple material composition of the filler pieceallows the manufacturer to tune its stiffness so that, when the filler pieceis bonded into the body, the stiffness is correct for the coefficient of restitution (COR) and the weight is correctly positioned to provide a low center of gravity (CG). The third embodiment, shown in, has most of the same characteristics as the second embodiment, except that the through-holesvary in size, shape, and length across the compliance zone.

In the fourth embodiment, shown in, the through-openingsare all disposed proximate to and parallel with the face opening, and the filler pieceis configured so that only the lower modulus cover piececomprises the extensionsthat engage with and fill the through-holes. In this way, the portion of the filler piececomprising a low modulus material is closest to the striking facewhen the face cupis fully engaged with the body. Behind each through-openingis a peg or extensionthat engages a socketwithin the cover pieceto help orient the cover piecewithin the compliance zoneand provides additional bonding area. As shown in, the inner portionand cover piece of the filler pieceare shaped so that they fit together like puzzle pieces.

In each of the embodiments, the solewithin the compliance zonepreferably has a variable thickness ranging from 0.01 to 0.05 inch, and may be optimized using artificial intelligence, machine learning, gradient-based optimization methods or stochastic optimization methods. As shown in, in the first embodiment, the face deflects downwards a first distance D. In an alternative embodiment that includes a solid chunk of steel on the inside of the sole, shown in, the face deflects downwards a second distance Dthat is less than D. In a sole thickness optimized embodiment, shown in, the face deflects downwards a third distance Dthat is greater than both Dand D.

Any of the embodiments disclosed herein may be combined with an internal weight that bridges a portion of the sole, such as those disclosed in U.S. Pat. Nos. 8,257,195, 8,328,661, 8,414,420, 8,425,346, 8,900,070, 8,926,448, 9,211,451, 9,782,652, and 10,080,932, the disclosure of each of which is hereby incorporated by reference in its entirety herein. This further improves the performance characteristics of the club.

From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. The section titles included herein also are not intended to be limiting. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims.