Golf Club Head with Ball Speed Control

It is a goal for golfers to reduce the total number of swings needed to complete a round of golf, thus reducing their total score. To achieve that goal, it is generally desirable to for a golfer to have a ball fly a consistent distance when struck by the same golf club and, for some clubs, also to have that ball travel a long distance. For instance, when a golfer slightly mishits a golf ball, the golfer does not want the golf ball to fly a significantly different distance. At the same time, the golfer also does not want to have a significantly reduced overall distance every time the golfer strikes the ball, even when the golfer strikes the ball in the “sweet spot” of the golf club. Additionally, it is also preferable for a golf club head to produce a pleasant sound to the golfer when the golf club head strikes the golf ball.

In some aspects, the techniques described herein relate to a golf club head including: a striking face having a front surface configured to strike a golf ball and a rear surface opposite the front surface; a periphery portion extending rearward from the striking face and including a sole, a topline opposite the sole, a heel side, a toe side opposite the heel side, and a back portion extending from the sole to the topline and from the heel side to the toe side; a hosel configured to receive a shaft, the hosel located on the heel side; a cavity formed between the periphery portion and the striking face; an aperture extending through the toe side and into the cavity; a support pad within the cavity attached to the back portion; and a damping element positioned between the support pad and the rear surface of the striking face.

In some aspects, the techniques described herein relate to a method of manufacturing a golf club head including: providing a striking face having a front surface configured to strike a golf ball and a rear surface opposite the front surface; providing a periphery portion extending rearward from the striking face and including a sole, a topline opposite the sole, a heel side, a toe side opposite the heel side, and a back portion extending from the sole to the topline and from the heel side to the toe side, wherein a cavity is formed between the periphery portion and the striking face; providing a hosel configured to receive a shaft, the hosel located on the heel side; providing an aperture extending through the toe side and into the cavity; and inserting a damping element through the aperture into the cavity.

The technologies described herein contemplate an iron-type golf club head that incorporates a damping element to promote more uniform ball speed across the striking face of the golf club head. Traditional thin-faced iron-type golf clubs generally produce less uniform launch velocities across the striking face due to increased compliance at the geometric center of the striking face. For example, when a golf club strikes a golf ball, the striking face of the club deflects and then springs forward, accelerating the golf ball off the striking face. While such a design may lead to large flight distances for a golf ball when struck in the center of the face, any off-center strike of the golf ball causes significant losses in flight distance. In comparison, an extremely thick face causes more uniform ball flight regardless of impact location, but it causes a significant loss in launch velocities. The present technology incorporates a damping element between a back portion of the hollow iron and the rear surface of the striking face. By including the damping element, the magnitude of the launch velocity may be reduced for strikes at the center of the face while improving uniformity of launch velocities across the striking face. The damping element compression and/or material may be selected to achieve desired deflection of the striking face depending on particular swing types and golfer needs.

depict a golf club headhaving a damping elementpositioned behind the striking face.depicts a front perspective view of the golf club head.depicts a rear view of the golf club head.depicts an exploded perspective view of the golf club head.depicts a front perspective view of the golf club headwith a toe portion removed.depicts a toe side view of the golf club headwith a toe portion removed.depicts a front perspective view of the golf club headwith the striking faceremoved.depicts a rear view of the striking face.depicts a side cross-sectional view of the golf club head.depicts a top cross-sectional view of the golf club head.

The golf club headillustrated inis an iron type golf club head having a hollow body construction and includes a periphery portionsurrounding and extending rearward from a striking face. The periphery portionincludes a sole, a toplineopposite the sole, a heel side, and a toe sideopposite the heel side. The periphery portionalso includes a back portionextending from the soleto the toplineand extending from the heel sideto the toe side. The golf club headincludes a hosellocated on the heel sideconfigured to receive a shaft (not shown). A cavityis formed between the periphery portionand the striking face. The striking facecan be formed separately and welded to the periphery portion. In other embodiments, the striking facemay be formed integrally with the periphery portion.

The golf club headfurther includes a damping elementlocated within the cavity. The damping elementhas a front portion that contacts a rear surfaceof the striking face. A rear portion of the damping elementcontacts a support pad. The support padis attached to the back portionof the golf club head. The support padincludes a raised lipprojecting towards the striking facewhich is critical for positioning the damping elementin the proper orientation on the support padduring assembly when visual inspection is obscured. The raised liphas a shape which complements the shape of the rear portion of the damping elementto prevent the damping elementfrom sliding or otherwise moving out of position once installed. In a preferred embodiment, the raised liphas an arcuate shape to complement a rounded rear portion of the damping element. In addition to the raised lip, the damping elementis generally held in place due to compression of the damping elementbetween the support padand the rear surfaceof the striking face. The damping elementis configured to be installed in a set position during assembly and remain in that position. The support padand the raised liphelp to ensure the damping elementis installed consistently and that the damping elementproperly and consistently engages the rear surfaceof the striking facefor optimal performance. An epoxy may be used to further secure the damping elementto the support padand/or the rear surfaceof the striking face. The epoxy may also provide acoustic damping for desired sound characteristics.

The damping elementmay have a generally frustoconical shape. In other examples, the damping elementmay have a cylindrical, hemispherical, cuboid, or prism shape. The support padis formed to substantially match the shape of the rear portion of the damping element. The support padmay be welded or otherwise attached to the back portion, or the support padmay be formed as part of the back portionduring a casting or forging process. The back portionmay also be machined to include the support pad. The support padis oriented substantially parallel to the rear surfaceof the striking face. The support paddoes not come into contact with the rear surfaceof the striking faceat maximum deflection thereof. The support paditself may be made of the same material as the back portion, such as a steel. The support padmay also be made from titanium, aluminum, composite, or ceramic materials.

The periphery portionincludes an apertureon the toe sideto allow installation of the damping elementwithin the cavity. This is critical for allowing the damping elementto be positioned between the support padand the rear surfaceof the striking faceafter the striking facehas been welded or otherwise attached to the periphery portion. In one embodiment where the striking faceis welded to the periphery portion, installing the damping elementafter the striking facehas been welded protects the damping elementfrom adverse heat effects that the damping elementwould be subjected to if it were installed prior to the welding process. In another embodiment where the striking faceis formed integrally with the periphery portion, installing the damping elementthrough the apertureprovides a minimally invasive assembly without the need for larger access openings and more complex finishing steps to enclose the cavity. The apertureis sized to allow the damping elementto slide through the apertureand be positioned between the support padand the rear surfaceof the striking face. In one embodiment, the aperturehas a maximum height in the sole-to-topline direction that approximately equals the maximum height of the damping element, and the aperturehas a maximum width in the front-to-rear direction that approximately equals the maximum width of the damping element. The raised lipassists in guiding the damping elementto its proper position. Once the damping elementis installed, a capcovers the apertureto prevent unwanted debris and moisture from entering the cavity. The capmay be attached using an adhesive. Alternatively, the capmay be attached by welding, preferably pulse welding. Pulse welding the capover the apertureinvolves welding smaller sections of the weld path in multiple passes. This is critical for allowing the golf club headto cool down in between welding passes to prevent excessive heat exposure to the damping element. Preferably, the apertureis sized just big enough to permit the damping elementto pass through during assembly. The relatively small size of the apertureprovides minimal heat exposure time for the damping elementwhen the capis welded over the aperture. Additionally, the location of the apertureon the toe sideof the periphery portionprovides a maximum separation distance from the heat exposure for the damping elementwhen the capis welded over the aperture.

In a preferred method of manufacturing the golf club head, the striking faceis welded to, or integrally formed with, the periphery portion. The damping elementis then inserted into the cavitythrough the aperturelocated on the toe sideof the periphery portion. The damping elementis positioned between the support padand the rear surfaceof the striking face. The raised lipassists in locating the proper positioning of the damping elementand helps prevent unwanted movement of the damping elementonce properly installed. The capis then welded or adhered to the periphery portionto cover the apertureand enclose the cavity.

In traditional thin face golf clubs, strikes at the geometric center of the striking face display the largest displacement of the striking face, and thus the greatest ball speeds. By disposing the damping elementproximate the geometric center of the striking face, the deflection of the striking faceat that point is reduced, thus reducing the ball speed. Portions of the striking facenot backed by the damping element, however, continue to deflect into the cavitycontributing to the speed of the golf ball. As such, a more uniform distribution of ball speeds resulting from ball strikes across the striking facefrom the heel sideto the toe sidemay be achieved.

The elasticity of the damping elementaffects the deflection of the striking face. For instance, a material with a lower elastic modulus allows for further deflection of the striking face, providing for higher maximum ball speeds but less uniformity of ball speeds. In contrast, a material with a higher elastic modulus further prevents deflection of the striking face, providing for lower maximum ball speeds but more uniformity of ball speeds. For some applications, a range of elastic moduli for the damping elementfrom about 4 MPa to about 15 GPa may be used. In other applications, a range of elastic moduli for the damping elementfrom about 15 to about 40 GPa may be used. To achieve the goal of having the carry distance of off-center shots closer to the carry distance of center shots, the material for the damping elementmay have an elastic modulus of about 40 GPa or greater, and more preferably about 70 GPa or greater. The material for the damping elementmay be a polymer, preferably silicone, to achieve the lower elastic modulus for higher ball speeds or a metal such as aluminum, steel, or titanium to achieve the higher elastic modulus for more consistent carry distances across the striking face. Although the maximum ball speed for impacts at the center decreases when the damping elementhas a higher elastic modulus, the speed retention across the striking faceis improved. This is desirable for golfers who want more consistent carry distance from strikes across the striking facerather than maximizing overall carry distance.

The damping elementhas a free thickness and an installed thickness measured in the front-to-rear direction. In some embodiments, the free thickness and the installed thickness of the damping elementcan be substantially the same. In this case, there would be little to no preload of the damping elementagainst the rear surfaceof the striking face. In other embodiments, the installed thickness can be lower than the free thickness, creating a preload force on the rear surfaceof the striking face. This preload force can change the coefficient of restitution of the striking face. In an additional embodiment, multiple versions of the damping elementmay be available with different free thicknesses to achieve a particular coefficient of restitution. Alternatively, the material of the damping elementcould be altered to change its stiffness, thus altering the coefficient of restitution of the golf club head.

A higher compression of the damping elementagainst the rear surfaceof the striking facefurther restricts the deflection of the striking face. In turn, further restriction of the deflection causes more uniform ball speeds across the striking face. However, the restriction on deflection also lowers the maximum ball speed from the center of the striking face. To achieve a golf club headthat produces further maximum distance, but does not need uniform ball speed across the striking face, the initial set compression of the damping elementcan be reduced, or a damping elementhaving a lower elastic modulus can be used. In contrast, to achieve a golf club headthat has more uniform ball speed across the striking face, the initial set compression of the damping elementcan be increased, or a damping elementhaving a higher elastic modulus can be used. This adjustability is critical for meeting a variety of specific performance needs for different individuals.

The inclusion of the damping elementin the golf club headprovides benefits in durability for the striking faceby reducing stress values displayed by the striking faceupon impact with a golf ball. Without the damping element, the von Mises stress levels are high and indicate that the striking facemay be susceptible to failure and/or early deterioration. Such von Mises stress values are lower with the damping elementand are indicative of a more durable golf club headthat is less likely to fail.

Another goal of the damping elementdescribed herein is to dissipate energy of the golf club head after it strikes a golf ball. As the striking faceand other portions of the golf club head vibrate, the damping elementin contact with those surfaces can dissipate the energy. This can change the sound produced by the golf club headby reducing the loudness and/or duration of the sound produced when the golf club headstrikes a golf ball.

As shown in, the periphery portionis configured to receive a first weight memberpositioned proximate the toe sideand a second weight memberpositioned proximate the heel side. The first weight memberhas an angled upper surfacesuch that the first weight memberhas a maximum height in a sole-to-topline direction at a toewardmost point and a minimum height in the sole-to-topline direction at a heelwardmost point. This shape of the first weight memberallows increased weight concentration toeward and soleward for higher moment of inertia and forgiveness. The second weight memberhas an angled upper surfacesuch that the second weight memberhas a maximum height in a sole-to-topline direction at a heelwardmost point and a minimum height in the sole-to-topline direction at a toewardmost point. This shape of the second weight memberallows increased weight concentration heelward and soleward for higher moment of inertia and forgiveness.

As shown in, the striking facehas a thickness that varies from a front surfaceto the rear surfaceto further promote more uniform ball speed across the striking faceof the golf club head. The striking faceincludes a thickened portionwhich at least partially overlaps a vertical plane perpendicular to a ground plane and passing through the face center of the golf club headwhen in an address position. The thickened portionis preferably between 1.6 mm and 2.6 mm thick, more preferably between 1.8 mm and 2.4 mm thick, and most preferably between 1.9 mm and 2.2 mm thick. The striking facealso includes a thinned portionat least partially surrounding the thickened portion. The thinned portionis preferably between 1.1 mm and 2.1 mm thick, more preferably between 1.35 mm and 1.85 mm thick, and most preferably between 1.5 mm and 1.7 mm thick. The thickness of the striking facemay gradually taper from the thickened portionto the thinned portionwhich may be located at an outer periphery of the striking face. The thickened portionis preferably between 10% and 50% thicker than the thinned portion, more preferably between 20% and 40% thicker than the thinned portion, and most preferably between 25% and 35% thicker than the thinned portion. These thicknesses and relative dimensions are critical for maintaining consistent ball speeds across the striking faceand controlling stresses experienced by the striking face. The front surface of the damping elementengages the rear surfaceof the striking faceat the thickened portion.

As shown in, the back portionof the golf club headmay include a pocketto allow a back weightto be inserted into the pocketfrom a rear of the golf club head. The back weightallows the swing weight of the golf club headto be customized based on player preference. The back weightmay be selected from a plurality of different masses having the same shape and volume to achieve a specific swing weight in a later stage of club head production. This allows for greater flexibility in customization of the golf club head. The back weightmay be fixed within the pocketby welding or adhesive bonding to prevent unwanted removal once the proper back weightis selected. In another embodiment, the back weightmay be removably secured within the pocketby clamping or threaded engagement to allow greater interchangeability of the back weight.

Other than in the operating examples, or unless otherwise expressly specified, all of the numerical ranges, amounts, values, and percentages may be read as if prefaced by the word “about” even though the term “about” may not expressly appear with the value, amount, or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following description and claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in any specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

Although specific embodiments and aspects were described herein and specific examples were provided, the scope of the invention is not limited to those specific embodiments and examples. One skilled in the art will recognize other embodiments or improvements that are within the scope and spirit of the present invention. Therefore, the specific structure, acts, or media are disclosed only as illustrative embodiments. The scope of the invention is defined by the following claims and any equivalents therein.