Iron-Type Golf Club Head

This application is a continuation of U.S. patent application Ser. No. 18/612,969, filed Mar. 21, 2024, which is a continuation of U.S. patent application Ser. No. 17/717,903, filed Apr. 11, 2022, which is a continuation of U.S. patent application Ser. No. 16/673,701, filed Nov. 4, 2019, which is a continuation of U.S. patent application Ser. No. 15/859,274, filed Dec. 29, 2017, which is a continuation-in-part of U.S. patent application Ser. No. 15/649,508, filed Jul. 13, 2017, which is a continuation of U.S. Pat. No. 9,731,176, issued Aug. 15, 2017, which is a continuation-in-part of U.S. patent application Ser. No. 14/843,856, filed Sep. 2, 2015, and which claims the benefit of U.S. Provisional Patent Application No. 62/099,012, filed on Dec. 31, 2014, and U.S. Provisional Patent Application No. 62/098,707, filed on Dec. 31, 2014, all of which are incorporated herein by reference in their entireties. This application additionally references U.S. patent application Ser. No. 15/706,632, filed Sep. 15, 2017, which is a continuation-in-part of U.S. patent application Ser. No. 15/394,549, filed Dec. 29, 2016, both of which are incorporated herein by reference in their entireties. This application also references U.S. patent application Ser. No. 14/145,761, filed Dec. 31, 2013, which claims priority to U.S. Provisional Patent Application No. 61/903,185, filed Nov. 12, 2013, both of which are hereby incorporated by reference herein in their entireties. This application further references U.S. patent application Ser. No. 13/830,293, filed Mar. 14, 2013, which claims priority to U.S. Provisional Patent Application No. 61/657,675, filed Jun. 8, 2012, both of which are hereby incorporated by reference herein in their entireties. This application additionally references U.S. Pat. No. 8,353,786, filed Dec. 28, 2007, which is incorporated by reference herein in its entirety.

This disclosure relates generally to iron-type golf club heads, and more particularly to iron-type golf club heads with an acoustic mode altering and dampening bridge bar.

The performance of golf equipment is continuously advancing due to the development of innovative clubs and club designs. While all clubs in a golfer's bag are important, both scratch and novice golfers rely on the performance and feel of iron-type golf clubs (“irons”) for many commonly encountered playing situations.

Irons are generally configured in a set that includes clubs of varying loft, with shaft lengths and club head weights selected to maintain an approximately constant “swing weight” so that the golfer perceives a common “feel” or “balance” in swinging both the low-lofted irons and high-lofted irons in a set. The size of an iron's “sweet spot” is generally related to the size (i.e., surface area) of the iron's strike face, and iron sets are available with oversize club heads to provide a large sweet spot that is desirable to many golfers.

Conventional “blade” type irons have been largely displaced (especially for novice golfers) by so-called “perimeter weighted” irons, which include “cavity-back” and “hollow” iron designs. Cavity-back irons have an open cavity directly behind the strike plate, which permits club head mass to be distributed about the perimeter of the strike plate. Such cavity-back irons tend to be more forgiving to off-center hits. Hollow irons have features similar to cavity-back irons, but the cavity is enclosed by a rear wall to form a hollow region behind the strike plate. Perimeter weighted, cavity-back, and hollow iron designs permit club designers to redistribute club head mass to achieve intended playing characteristics associated with, for example, placement of a center of gravity (“CG”) or a moment of inertia (“MOI”) of the golf club head.

In addition, even with perimeter weighting, significant portions of the club head mass, such as the mass associated with the hosel, topline, or strike plate, are unavailable for redistribution. For example, the strike plate must withstand repeated strikes both on the driving range and on the course, requiring significant strength for durability.

Golf club manufacturers are consistently attempting to design golf clubs that are easier to hit and offer golfers greater forgiveness, such as when the ball is not struck directly at a “sweet spot” or center face of the strike face. As those skilled in the art will appreciate, many golf club head designs have been developed and proposed for assisting golfers in learning and mastering the game of golf.

With regard to iron-type club heads, cavity-back club heads have been developed. Cavity-back golf clubs shift the weight of the club head toward the outer perimeter of the club head. By shifting the weight in this manner, the CG of the club head is pushed toward the sole of the club head, thereby providing a club head that promotes better performance. In addition, weight is shifted to the toe and heel of the club head, which helps to expand the sweet spot and minimize negative performance characteristics associated with off-center strikes of a golf ball.

Shifting weight to the sole of the club head lowers the CG of the club head resulting in a golf club that launches the ball more easily and with greater backspin. Golf club designers often focus on the vertical CG of the golf club relative to the ground when the golf club is soled and in a proper address position. This vertical CG measurement is often referred to as Zup or Z-up or CG Z-up. Decreasing Z-up is preferable to increasing Z-up. Golf club designers seek to achieve a low Z-up both for golf clubs designed for low handicap golfers and high handicap golfers. For example, a low Z-up helps to maintain similar launch angles, but increases ball speed and distance, for low handicap golfers or a low Z-up helps to launch the ball more easily in the air for high handicap golfers. Additionally, placing weight at the toe increases the MOI of the golf club resulting in a golf club that resists twisting and is thereby easier to hit straight even on mishits.

As club manufacturers have learned to assist golfers by shifting the CG toward the sole of the club head, a wide variety of designs have been developed. Unfortunately, many of these designs shift the center of gravity toward the sole and perimeter of the club head at the expense of the appearance of the club head. For example, one method of lowering the CG is to simply decrease the face height at the toe and make it closer in height to the face height at the heel of the club resulting in a very untraditional looking club. This is highly undesirable as golfers have become familiar with a certain traditional style of club head and alteration of that style often adversely affects their mental outlook when addressing a ball prior to strike the ball. As such, a need exists for an improved club head which achieves the goal of shifting the CG further toward the sole and perimeter of the club head without substantially altering the appearance of a traditional cavity-back club head.

Unfortunately, the acoustical properties of a golf club head may be negatively impacted by relocating mass and lowering Z-up on the golf club head. The acoustical properties of golf club heads (e.g., the sound the golf club head generates upon impact with a golf ball) affect the overall feel of the golf club by providing instant auditory feedback to the user of the golf club. For example, the auditory feedback can provide an indication as to how well the golf ball was struck by the club, thereby promoting user confidence.

The sound generated by a golf club is based on the rate, or frequency, at which the golf club head vibrates and the duration of the vibration upon impact with a golf ball. Generally, for iron-type golf clubs, a desired first mode frequency is generally around 3,000 Hz and preferably greater than 3,200 Hz. Additionally, the duration of the first mode frequency is important because a longer duration may feel like a golf ball was poorly struck, which results in less confidence for the golfer even when the golf ball was well struck. Generally, for iron-type golf club heads, a desired first mode frequency duration is generally less than 10 ms and preferably less than 7 ms. Some conventional golf club heads employ features designed to increase the vibrational frequency of the golf club head and decrease the frequency duration of the golf club head. However, such features may fail to increase the vibration frequency of the golf club heads to desirable levels (e.g., a desirable upward shift in the vibration frequency) and/or decrease the frequency duration to desirable level.

Additionally, the coefficient of restitution (“COR”) of a golf club head may be negatively impacted by relocating mass and lowering Z-up on the golf club head. The COR of a golf club head is a measurement of the energy loss or retention when the golf ball is impact by the golf club head. Generally, the higher the COR, the more efficient the transfer of energy from the golf club head to the golf ball and the longer the golf shot. For some conventional golf club heads, lowering the Z-up of the golf club head results in an undesirable lowering of the COR.

Conventional iron-type golf club heads may not achieve desired first and fourth mode frequencies and frequency durations and desired COR characteristics while providing the performance benefits afforded by a low Z-up. Accordingly, it would be desirable to provide a golf club head that lowers the Z-up while maintaining desirable vibration frequency and duration characteristics and a desirable COR.

The subject matter of the present application has been developed in response to the present state of the art, and in particular, in response to the shortcomings of conventional iron-type golf club heads, that have not yet been fully solved by currently available techniques. Accordingly, the subject matter of the present application has been developed to provide an iron-type golf club head that overcomes at least some of the above-discussed shortcomings of prior art techniques. More specifically, described herein are embodiments of an iron-type golf club head that lowers the Z-up while maintaining desirable vibration frequency and duration characteristics and a desirable COR.

Disclosed herein is an iron-type golf club head comprising a body comprising a heel portion, a sole portion, a toe portion, and a topline portion. The topline portion has a mass per unit length of between 0.09 g/mm and 0.40 g/mm. The golf club head also comprises a strike plate coupled to the body at a front portion of the golf club head and a cavity defined between the topline portion, the sole portion, and the strike plate. The golf club head further comprises a bridge bar at a rear portion of the golf club head. The bridge bar spans the cavity, is spaced apart from the strike plate, and is rigidly fixed to and extends uprightly between the sole portion and the topline portion. The bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm. The preceding subject matter of this paragraph characterizes example 1 of the present disclosure.

A Z-up of the golf club head is below about 20 mm. The topline portion comprises weight reducing features that shift a Z-up of the golf club head downward by at least 0.4 mm. The bridge bar shifts the Z-up of the golf club head upward by less than 2.0 mm. The preceding subject matter of this paragraph characterizes example 2 of the present disclosure, wherein example 2 also includes the subject matter according to example 1, above.

The weight reducing features shift the Z-up of the golf club head downward by at least 1.0 mm. The preceding subject matter of this paragraph characterizes example 3 of the present disclosure, wherein example 3 also includes the subject matter according to example 2, above.

The topline portion comprises weight reducing and stiffening features comprising a rearwardly and downwardly directed overhang and a plurality of ribs coupled to an underside of the overhang. The preceding subject matter of this paragraph characterizes example 4 of the present disclosure, wherein example 4 also includes the subject matter according to any one of examples 1-3, above.

The bridge bar is fixed to one rib of the plurality of ribs. The preceding subject matter of this paragraph characterizes example 5 of the present disclosure, wherein example 5 also includes the subject matter according to example 4, above.

The bridge bar is hollow. The preceding subject matter of this paragraph characterizes example 6 of the present disclosure, wherein example 6 also includes the subject matter according to any one of examples 1-5, above.

The bridge bar comprises at least one web and at least one flange angled relative to the at least one web. The preceding subject matter of this paragraph characterizes example 7 of the present disclosure, wherein example 7 also includes the subject matter according to any one of examples 1-6, above.

A cross-section of the bridge bar is T-shaped. The preceding subject matter of this paragraph characterizes example 8 of the present disclosure, wherein example 8 also includes the subject matter according to any one of examples 1-7, above.

The bridge bar has a mass per unit length of between 0.09 g/mm and 0.25 g/mm. The preceding subject matter of this paragraph characterizes example 9 of the present disclosure, wherein example 9 also includes the subject matter according to any one of examples 1-8, above.

The golf club head has a coefficient of restitution (COR) greater than 0.79. The preceding subject matter of this paragraph characterizes example 10 of the present disclosure, wherein example 10 also includes the subject matter according to any one of examples 1-9, above.

A Z-up of the golf club head is below about 20 mm. The preceding subject matter of this paragraph characterizes example 11 of the present disclosure, wherein example 11 also includes the subject matter according to any one of examples 1-10, above.

A Z-up of the golf club head is below about 18 mm. The preceding subject matter of this paragraph characterizes example 12 of the present disclosure, wherein example 12 also includes the subject matter according to example 11, above.

The golf club head further comprises a channel formed in the sole portion and extending substantially parallel to the strike plate. The preceding subject matter of this paragraph characterizes example 13 of the present disclosure, wherein example 13 also includes the subject matter according to any one of examples 1-12, above.

The strike plate has a minimum thickness less than or equal to 2 mm. The preceding subject matter of this paragraph characterizes example 14 of the present disclosure, wherein example 14 also includes the subject matter according to any one of examples 1-13, above.

The golf club head further comprises a rear panel adjacent the bridge bar and covering the cavity. The rear panel is made of a material different than the bridge bar. The preceding subject matter of this paragraph characterizes example 15 of the present disclosure, wherein example 15 also includes the subject matter according to any one of examples 1-14, above.

The bridge bar is made of a metal alloy and the rear panel is made of a non-metal material having a density between 1 g/cc and 2 g/cc. The preceding subject matter of this paragraph characterizes example 16 of the present disclosure, wherein example 16 also includes the subject matter according to example 15, above.

The non-metal material is a fiber-reinforced polymer. The preceding subject matter of this paragraph characterizes example 17 of the present disclosure, wherein example 17 also includes the subject matter according to example 16, above.

An areal mass of the rear portion of the golf club head between the topline portion, the sole portion, the toe portion, and the heel portion is between 0.0005 g/mm2 and 0.00925 g/mm2. The preceding subject matter of this paragraph characterizes example 18 of the present disclosure, wherein example 18 also includes the subject matter according to any one of examples 1-17, above.

Also disclosed herein is an iron-type golf club head comprising a body comprising a heel portion, a sole portion, a toe portion, and a topline portion. The golf club head also comprises a strike plate coupled to the body at a front portion of the golf club head, a cavity defined between the topline portion, the sole portion, and the strike plate, and a bridge bar at a rear portion of the golf club head. The bridge bar spans the cavity, is spaced apart from the strike plate, and is rigidly fixed to and extends uprightly between the sole portion and the topline portion. The bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm. Furthermore, the bridge bar increases a frequency, at which a maximum displacement of at least one location of a plurality of locations along the topline portion occurs, by at least 100 Hz. The preceding subject matter of this paragraph characterizes example 19 of the present disclosure.

The bridge bar increases the frequency by at least 400 Hz. The preceding subject matter of this paragraph characterizes example 20 of the present disclosure, wherein example 20 also includes the subject matter according to example 19, above.

A first lowest frequency, at which a first maximum displacement of at least one location of the plurality of locations along the topline portion occurs, is at least 3,500 Hz. The preceding subject matter of this paragraph characterizes example 21 of the present disclosure, wherein example 21 also includes the subject matter according to any one of examples 19 or 20, above.

A fourth lowest frequency, at which a fourth maximum displacement of the at least one location of the plurality of locations along the topline portion occurs, is at least 6,000 Hz. The preceding subject matter of this paragraph characterizes example 22 of the present disclosure, wherein example 22 also includes the subject matter according to example 21, above.

Further disclosed herein is an iron-type golf club head comprising a body comprising a heel portion, a sole portion, a toe portion, and a topline portion. The golf club head further comprises a strike plate coupled to the body at a front portion of the golf club head and a cavity defined between the topline portion, the sole portion, and the strike plate. The golf club head further comprises a bridge bar at a rear portion of the golf club head. The bridge bar spans the cavity, is spaced apart from the strike plate, and is rigidly fixed to and extends uprightly between the sole portion and the topline portion. The bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm. The iron-type golf club head with the bridge bar has a first frequency at which a first maximum displacement occurs, a second frequency at which a second maximum displacement occurs, a third frequency at which a third maximum displacement occurs, and a fourth frequency at which a fourth maximum displacement occurs. Removing the bridge bar decreases at least one of the first frequency, the second frequency, the third frequency, and the fourth frequency by at least 200 Hz. The preceding subject matter of this paragraph characterizes example 23 of the present disclosure.

The described features, structures, advantages, and/or characteristics of the subject matter of the present disclosure may be combined in any suitable manner in one or more embodiments and/or implementations. In the following description, numerous specific details are provided to impart a thorough understanding of embodiments of the subject matter of the present disclosure. One skilled in the relevant art will recognize that the subject matter of the present disclosure may be practiced without one or more of the specific features, details, components, materials, and/or methods of a particular embodiment or implementation. In other instances, additional features and advantages may be recognized in certain embodiments and/or implementations that may not be present in all embodiments or implementations. Further, in some instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the subject matter of the present disclosure. The features and advantages of the subject matter of the present disclosure will become more fully apparent from the following description and appended claims, or may be learned by the practice of the subject matter as set forth hereinafter.

The present disclosure describes iron-type golf club heads that include a body and a strike plate. The body includes a heel portion, a toe portion, a topline portion, a sole portion, and a hosel configured to attach the club head to a shaft to form a golf club. In various embodiments, the body defines a front opening configured to receive the strike plate at a front rim formed around a periphery of the front opening. In various other embodiments, the strike plate is formed integrally (such as by casting) with the body. The body further includes a bridge bar that spans between and is fixed to the topline portion and the sole portion along a rear of the body. The particular configuration of the bridge bar, in conjunction with other features of the body, helps to promote a higher or upward shift in modal frequency of the golf club head while providing a desirably high COR and low Z-up.

illustrates one embodiment of an iron-type golf club headincluding a bodyhaving a heel portion, a toe portion, a sole portion, a topline portion, and a hosel. The golf club headis shown inin a normal address position with the sole portionresting upon a ground plane, which is assumed to be perfectly flat. As used herein, “normal address position” means the position of the golf club headwhen a vector normal to a geometric center of a strike faceof the golf club headlies substantially in a first vertical plane (i.e., a plane perpendicular to the ground plane), a centerline axisof the hosellies substantially in a second vertical plane, and the first vertical plane and the second vertical plane substantially perpendicularly intersect. The geometric center of the strike faceis determined using the procedures described in the USGA “Procedure for Measuring the Flexibility of a Golf Club head,” Revision 2.0, Mar. 25, 2005. The strike faceis the front surface of a strike plateof the golf club head. The strike facehas a rear surface, opposite the strike face(see, e.g.,). In some embodiments, the strike plate has a thickness that is less than 2.0 mm, such as between 1.0 mm and 1.75 mm. Additionally or alternatively, the strike plate may have an average thickness less than or equal to 2 mm, such as an average thickness between 1.0 mm and 2.0 mm, such as an average thickness between 1.25 mm and 1.75 mm. In some embodiments, the strike plate has a thickness that varies. In some embodiments, the strike plate has a thinned region coinciding and surrounding the center of the face such that the center face region of the strike plate is the thinnest region of the strike plate. In other embodiments, the strike plate has a thickened region coinciding and surrounding the center of the face such that the center face region of the strike plate is the thickest region of the strike plate.

As shown in, a lower tangent pointon the outer surface of the golf club head, of a lineforming a 45° angle relative to the ground plane, defines a demarcation boundary between the sole portionand the toe portion. Similarly, an upper tangent pointon the outer surface of the golf club headof a lineforming a 45° angle relative to the ground planedefines a demarcation boundary between the topline portionand the toe portion. In other words, the portion of the golf club headthat is above and to the left (as viewed in) of the lower tangent pointand below and to the left (as viewed in) of the upper tangent pointis the toe portion.

The strike faceincludes groovesdesigned to impact and affect spin characteristics of a golf ball struck by the golf club head. In some embodiments, the toe portionmay be defined to be any portion of the golf club headthat is toeward of the grooves. In some embodiments, the bodyand the strike plateof the golf club headcan be a single unitary cast piece, while in other embodiments, the strike platecan be formed separately and be adhesively or mechanically attached to the bodyof the golf club head.

show an ideal strike locationon the strike faceand respective coordinate system with the ideal strike locationat the origin. As used herein, the ideal strike locationis located on the strike faceand coincides with the location of the CGof the golf club headalong an x-axisand is offset from a leading edgeof the golf club head(defined as the midpoint of a radius connecting the sole portionand the strike face) by a distance d, which is 16.5 mm in some implementations, along the strike face, as shown in. The x-axis, a y-axis, and a z-axisintersect at the ideal strike location, which defines the origin of the orthogonal axes. With the golf club headin the normal address position, the x-axisis parallel to the ground planeand is oriented perpendicular to a normal extending from the strike faceat the ideal strike location. The y-axisis also parallel to the ground planeand is perpendicular to the x-axis. The z-axisis oriented perpendicular to the ground plane, and thus is perpendicular to the x-axisand the y-axis. In addition, a z-up axiscan be defined as an axis perpendicular to the ground planeand having an origin at the ground plane.

In certain embodiments, a desirable CG-y location is between about 0.25 mm to about 20 mm along the y-axistoward the rear portion of the club head. Additionally, according to some embodiments, a desirable CG-z location is between about 12 mm to about 25 mm along the z-up axis.

The golf club headmay be of solid (also referred to as “blades” and/or “musclebacks”), hollow, cavity back, or other construction. However, in the illustrated embodiments, the golf club headis depicted as having a cavity-back construction because the golf club headincludes an open cavitybehind the strike plate(see, e.g.,).shows a cross-sectional side view, along the cross-section lines-of, of the golf club head.

In the embodiment shown in, the groovesare located on the strike facesuch that they are centered along the X-axisabout the ideal strike location(such that the ideal strike locationis located within the strike faceon an imaginary line that is both perpendicular to and that passes through the midpoint of the longest score-line groove). In other embodiments (not shown in the drawings), the groovesmay be shifted along the X-axisto the toe side or the heel side relative to the ideal striking location, the groovesmay be aligned along an axis that is not parallel to the ground plane, the groovesmay have discontinuities along their lengths, or the strike facemay not have grooves. Still other shapes, alignments, and/or orientations of grooveson the strike faceare also possible.

In reference to, the golf club headhas a sole length LB (i.e., length of the sole) and a club head height HCH (i.e., height of the golf club head). The sole length LB is defined as the distance between two points,projected onto the ground plane. The heel side pointis defined as the intersection of a projection of the hosel axisonto the ground plane. The toe side pointis defined as the intersection point of the vertical projection of the lower tangent point (described above) onto the ground plane. Accordingly, the distance between the heel side pointand the toe side pointis the sole length LB of the golf club head. The club head height HCH is defined as the distance between the ground planeand the uppermost point of the club head in a direction parallel to the z-up axis.

Referring to, the golf club headincludes a club head front-to-back depth DCH defined as the distance between two points,projected onto the ground plane. A forward end pointis defined as the intersection of the projection of the leading edgeonto the ground planein a direction parallel to the z-up axis. A rearward end pointis defined as the intersection of the projection of the rearward-most point of the club head onto the ground planein a direction parallel to the z-up axis. Accordingly, the distance between the forward end pointand rearward end pointof the golf club headis the depth DCH of the golf club head.

Referring to, the bodyof the golf club headfurther includes a sole barthat defines a rearward portion of the sole portionof the body. The sole barhas a relatively large thickness in relation to the strike plateand other portions of the golf club head. Accordingly, the sole baraccounts for a significant portion of the mass of the golf club headand effectively shifts the CG of the golf club headrelatively lower and rearward. As particularly shown in, the sole portionof the bodyincludes a forward portionwith a thickness less than that of the sole bar. The forward portionis located between the sole barand the strike face. As described more fully below, the bodyincludes a channelformed in the sole portionbetween the sole barand the strike faceto effectively separate the sole barfrom the strike face. The channelis located closer to the forward end pointthan the rearward end point.