Low and back crown mass for a golf club head

A golf club head includes a body having a crown defining a perimeter of the club head, a sole opposite the crown, a toe end opposite a heel end, a back end, and a hosel, the body further including a club face, an exterior side, an interior side, a head center of gravity, and a weight member positioned on one of the exterior side or the interior side of the crown.

FIELD OF THE INVENTION

The present disclosure relates to a golf club, and more specifically to a mass of discretionary weight on a crown of a golf club head that increases a moment of inertia by positioning the weight an increased distance away from a center of gravity.

BACKGROUND

Golf clubs take various forms, for example a wood, a hybrid, an iron, a wedge, or a putter, and these clubs generally differ in head shape and design (e.g., the difference between a wood and an iron), club head material(s), shaft material(s), club length, and club loft.

Woods and hybrids generally have a longer shaft and lower loft than irons and wedges. Thus, a golf ball that is struck with a wood or a hybrid generally travels a greater distance than a golf ball struck with an iron or a wedge. While a longer shaft and a lower loft provide increased golf ball travel distance, this combination also results in less forgiveness. The longer shaft requires a golfer to stand farther away from the golf ball at address. This leads to greater difficulty during the golf swing to return the club head squarely to impact the golf ball. A golf club that is slightly open or slightly closed at impact results in reduced accuracy as the golf ball is not launched on the desired target line. Further, the higher swing speeds from the longer length shaft can lead to greater difficulty in making consistent contact with the center or “sweet spot” of the golf club face. Off-center contact can lead to imparting increased side spin on the golf ball. At reduced lofts of woods and hybrids, less back spin is imparted on the golf ball at impact, further exacerbating imparted side spin and leading to undesirable hooks or slices, which further decrease accuracy.

To improve directional forgiveness, golf club manufacturers have made efforts to increase the moment of inertia of a golf club at impact. The moment of inertia (or “MOI”) is a measure of a body's resistance to angular acceleration, or twisting. The higher the MOI of a golf club head, the more the golf club head resists twisting at impact, improving golf ball accuracy, especially on off-center contact (or mishits). In addition, the increased stability of a higher MOI golf club head results in a golf ball losing less ball speed on off-center contact due to reduced energy loss associated with reduced twisting. A higher MOI of a golf club head further increases consistency in spin rate and launch angle of a golf ball on off-center contact.

While woods and hybrids have a variety of known designs, there is a need for enhancing directional forgiveness (e.g., a reduction in side-to-side variation) to improve accuracy, especially on off-center hits (e.g., contact of the golf ball with a location on the golf club face other than the sweet spot).

DETAILED DESCRIPTION

One embodiment includes a club head design that increases and/or maximizes golf club head moment of inertia (MOI) by positioning discretionary weight farther away from the head center of gravity than other known golf club heads. Discretionary weight, or a portion thereof, is positioned on the exterior side of the club head crown in the form of a weight member that extends about a portion of a perimeter defined by the crown at the back of the club head. By positioning the weight member on an exterior surface of the club head crown, the distance between the center of gravity and the discretionary weight is increased over club heads that position discretionary weight on an interior surface or the exterior surface of the sole of the club head. Therefore, the MOI of the club head is increased to provide greater forgiveness and consistency in direction, trajectory, and distance.

Other features and aspects will become apparent by consideration of the following detailed description and accompanying drawings. Before any embodiments of the disclosure are explained in detail, it should be understood that the disclosure is not limited in its application to the details or construction and the arrangement of components as set forth in the following description or as illustrated in the drawings. The disclosure is capable of supporting other embodiments and of being practiced or of being carried out in various ways. It should be understood that the description of specific embodiments is not intended to limit the disclosure from covering all modifications, equivalents and alternatives falling within the spirit and scope of the disclosure. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

Discretionary weight, as described herein, refers to a portion of the total weight of the club head that can be moved to optimize performance without impacting the structural integrity of the club head.

The terms “couple,” “coupled,” “couples,” “coupling,” and the like should be broadly understood and refer to connecting two or more elements, mechanically or otherwise. Coupling (whether mechanical or otherwise) may be for any length of time, e.g., permanent or semi-permanent or only for an instant.

For ease of discussion and understanding, and for purposes of description only, the following detailed description illustrates a golf club head10as a fairway wood. It should be appreciated that the fairway wood is provided for purposes of illustration of the discretionary weight positioning on an exterior surface of the club head10that increases MOI and directional forgiveness, as disclosed herein. The disclosed discretionary weight positioning may be used on any desired wood, hybrid, or other club that has discretionary weight that may be moved to increase MOI. For example, the club head10may include, but is not limited to, a driver, a fairway wood, or a hybrid.

FIGS. 1-4illustrate an embodiment of the golf club head10for use with a golf club. Referring generally toFIGS. 1-4, the club head10includes a body12, the body12having a toe or toe end14opposite a heel or heel end18, a crown30opposite a sole34, a back or rear or back end26, and a hosel axis36extending through the center of a hosel38. The club head10further includes a face or club face or strike face22opposite the back end26, an exterior side78, and an interior side82, the club face22having a geometric center.

Referring toFIGS. 1 and 4, the crown30defines a crown surface curvature or profile84when viewed from a side view (FIG. 4) and a perimeter74when viewed from a top view (FIG. 1). The club head10further includes a head center of gravity86, and a weight member or plurality of weight members70positioned adjacent to the crown30, the weight member70having a weight member center of gravity88.

Referring toFIGS. 1 and 4, the head center of gravity86defines an origin of a coordinate system including an x-axis500, a y-axis510, and a z-axis520. The x-axis extends500through the head center of gravity86from the toe end14to the heel end18, the y-axis510extends through the head center of gravity86from the crown30to the sole34, and the z-axis520extends through the head center of gravity86from the club face12to the back26. For additional guidance, the x-axis500and z-axis520are arranged to coincide with numbers on an analog clock, with the z-axis520extending between 12 o'clock (“12” through the club face22) and 6 o'clock (“6” through the back26), and the x-axis500extending between 3 o'clock (“3” through the toe end14) and 9 o'clock (“9” through the heel end18).

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70includes a first end92positioned near the toe14and a second end96positioned near the heel18. In the illustrated embodiments ofFIGS. 1-4, the weight member70is positioned on the exterior of the crown and about a portion of a perimeter defined by the crown. The weight member70has a width200and a projection height204. The projection height204may vary along the width200of the weight member70, defining a projection height profile208.

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70has an elongated shape wherein the projection height profile208of the weight member70is substantially constant from the first end92to the second end96. Specifically, the projection height204of the weight member70varies along the width200defining an arcuate or curved shape. The curved projection height profile208has a maximum projection height212positioned approximately centrally along the width200of the weight member70, wherein the maximum projection height212is approximately constant from the first end92to the second end96of the weight member70.

In other embodiments, the weight member70may be any suitable shape, including, but not limited to a polygon or a shape with at least one curved surface. For example, the weight member70may be round, triangular, elliptical, trapezoidal, or any other shape. Further, the projection height profile208of the weight member may have any profile and may be constant or may vary along the width200of the weight member70in any capacity. For example, the projection height profile208may be linear, quadratic, exponential, or a combination of the above described projection height profiles208such that the maximum projection height212may be positioned anywhere along the width200of the weight member70. Further still, the projection height profile208and the maximum projection height212may vary from the first end92to the second end96of the weight member70.

In the illustrated embodiment, shown inFIG. 5, the maximum projection height212is greater than the maximum projection height of known golf club heads having weight members positioned on the sole. In known golf club heads having sole weight members, the weight member center of gravity is typically positioned within the club head. In known golf club heads having sole weight members wherein the weight member center of gravity is positioned outside the club head, the maximum projection height is significantly smaller than the maximum projection height212in the illustrated embodiment.

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70and the crown surface curvature84together define a modified crown surface curvature or profile85(shown inFIG. 3) that has a non-linear profile or a bimodal profile or a bimodal slope that extends from the club face22to the back end26at a portion of the perimeter74defined by the crown30. Generally, the slope of modified crown surface profile85decreases from the portion of the crown30in vertical alignment with the center of gravity86(FIG. 3) to the weight member70, ceases decreasing or increases along a portion of the weight member70, and then decreases to the back end26adjacent or at a portion of the perimeter74. In other embodiments, the modified crown surface profile85may vary differently than the modified crown surface profile85described herein. For example, the modified crown surface profile85may be linear, quadratic, exponential, or a combination of the above described modified crown surface profiles85.

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70is positioned adjacent to the exterior side78of the crown30and projects above or from or extends above the crown surface curvature84. In other embodiments, the weight member70may be positioned adjacent to the interior side82of the crown30and project below or extend below the crown surface curvature84.

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70is a continuous portion or band that extends adjacent to, near, or along a portion of the perimeter74defined by the crown30. In other embodiments, the weight member70may include a plurality of weights or weight members70that extend adjacent to, near, or along a portion of the perimeter74defined by the crown30. Further, one or more weight members70may be positioned on the exterior side78of the crown30, one or more weight members70may be positioned on the interior side82of the crown30, or one or more weight members70may be positioned on the exterior side78and the interior side82of the crown30.

In the illustrated embodiment, referring toFIGS. 1-4, the weight member70is positioned adjacent to the crown30such that the weight member70extends through quadrants defined on the back side26of the x-axis500extending between the toe and heel ends14,18. The weight member70is also intersected by the z-axis520, such that the z-axis520bisects the weight member70at 6 o'clock. In other words, the weight member center of gravity88is positioned at the 6 o'clock position when viewed from a top view, as shown inFIG. 1. In other embodiments, the weight member70may be provided at any location in the quadrants defined on a side of the x-axis500toward the back26of the club head10. Stated another way, the weight member70may be provided at any location within the 3 o'clock to 6 o'clock quadrant such that the weight member center of gravity88is positioned closer to the toe end14than to the heel end18, and/or at any location within the 6 o'clock to 9 o'clock quadrant such that the weight member center of gravity88is positioned closer to the heel end18than to the toe end14.

The illustrated embodiment, shown inFIGS. 1-2, depicts the weight member70positioned on the exterior side78of the crown30and extending about the crown30in an arcuate or curved manner, matching the curvature defined by the perimeter74of the crown30. The weight member70is positioned on the crown30within the perimeter74as viewed inFIG. 1.

Referring toFIGS. 1-5, and in particularFIG. 5, the weight member center of gravity88is positioned at a perpendicular distance220from the crown30. The weight member70includes a curved center line250extending through the weight member center of gravity88, following the profile of the weight member70such that at any position along the perimeter74of the crown30, the curved center line250is positioned at the perpendicular distance220from the crown30.

In many embodiments, the weight member70further includes a length measured along the center line250extending from the first end92to the second end96. In many embodiments, the length may range from 0.10-6.0 inches (2.54-152.4 mm). For example, the length may be between 2.5 inches (63.5 mm) and 5.5 inches (136.7 mm), or the length may be greater than approximately 0.10 inches (2.54 mm), greater than approximately 0.50 inches (12.7 mm), greater than approximately 1.0 inches (25.4 mm), greater than approximately 1.5 inches (38.1 mm), greater than approximately 2.0 inches (50.8 mm), or greater than approximately 2.5 inches (63.5 mm). For further example, the length can be approximately 2.5 inches (63.4 mm), 3.0 inches (76.2 mm), 3.5 inches (88.9 mm), 4.0 inches (101.6 mm), 4.5 inches (114.3 mm), or 5.0 inches (127 mm).

In the illustrated embodiment, the weight member70is positioned on the exterior side78of the crown30to maximize the distance from the weight member70to the head center of gravity86. As depicted inFIGS. 4 and 5, the weight member70is positioned such that the curved center line250extends a first distance D1from the head center of gravity86in any particular position relative to the perimeter74of the club head10. The distance D1may vary with position along the perimeter74of the club head10. The first distance D1may be greater than any distance from the head center of gravity86to the interior side82or the exterior side78of the club head10on the crown30or sole34measured at the same particular position relative to the perimeter74of the club head10. For example,FIG. 4illustrates that the first distance D1is greater than both a second distance D2, which extends from the head center of gravity86to the interior side82of the crown30of the club head10, and a third distance D3, which extends from the head center of gravity86to the interior side82of the sole34of the club head10, wherein D1, D2, and D3are measured at approximately the 6 o'clock position along the perimeter74. The same relationship may apply to the distances D1, D2, and D3when measured at any other position along the perimeter74of the club head10, such as, for example, the 5 o'clock position or the 7 o'clock position.

The club head10may be made of any material such as titanium, steel, aluminum, other metals, metal alloys, composites, or any combination of materials. The weight member70may be made of the same material as the club head10, or the weight member70may be made of a different material than the club head10, such as titanium, steel, aluminum, other metals, metal alloys, composites, or any combination of materials. In embodiments where the weight member comprises a different material than the club head10, the density of the weight member70can be greater than the density of the club head.

In some embodiments, the density of the weight member70can vary. Referring toFIG. 12, the weight member70can have one or more high density regions90(e.g. region(s) of the weight member70having greater density than the remaining regions of the weight member70). For example, referring toFIG. 12a, the weight member can have a high density region90near the first end92to achieve a toe bias. For further example, referring toFIG. 12b, the weight member can have a high density region90near the second end96to achieve a heel bias. For further example, referring to FIG.12c, the weight member70can have a high density region90near the center of the weight member70. For further example, referring toFIG. 12d, the weight member70can have a plurality of high density regions90including a first high density region90near the first end92and a second high density region near the second end96. In other embodiments, the density of the weight member70can be greater in any position, plurality of positions, or combination of positions along the weight member70. Further, in other embodiments, the density of the weight member70can vary in discrete positions, or according to any profile. Further, in embodiments where the weight member includes one or more high density region(s)90, the remaining regions of the weight member70can comprise a shell or have a void to reduce the mass of the weight member70outside the high density region(s)90.

The weight member70has a mass or weight that can range from approximately 5 grams to approximately 150 grams, as described in further detail below. In embodiments where the weight member70includes one or more high density regions90, the high density region(s)90comprises at least a portion of the mass of the weight member70. In some embodiments, the high density region(s)90can comprise a majority of the mass of the weight member70. For example, the high density region(s)90can comprise approximately 30%, approximately 35%, approximately 40%, approximately 45%, approximately 50%, approximately 60%, approximately 65%, approximately 70%, approximately 75%, approximately 80%, approximately 85%, approximately 90%, or approximately 95% of the mass of the weight member70.

The weight member70has a mass or weight, wherein the weight of the weight member70may be a portion of the discretionary weight of the club head10, or the weight of the weight member70may be the same as the discretionary weight of the club head10. When the weight of the weight member70is a portion of the discretionary weight of the club head10, the remaining discretionary weight may be positioned in areas of the club head10other than the crown30, such as the sole34, the face22, the hosel38, or a combination of the above listed positions.

The amount of discretionary weight of the club head10varies with the type of club head10. For example, the discretionary weight varies with total weight and length of the club head10, and can range from 5 grams to 150 or more grams.FIG. 7depicts a table with ranges of total weight of the club head10, discretionary weight of the club head10, discretionary weight as a percentage of total weight of the club head10, and assembled golf club length for exemplary drivers, a fairway woods, and hybrids. For example, the discretionary weight may range from approximately 20-60 grams for a driver (approximately 15-35 percent of the total weight of the driver-type club head10), the discretionary weight may range from approximately 45-85 grams for a fairway wood (approximately 20-40 percent of the total weight of the wood-type club head10), and the discretionary weight may range from approximately 70-130 grams for a hybrid (approximately 25-55 percent of the total weight of the hybrid-type club head10). Generally, discretionary weight, measured as a percentage of total weight of the club head10, increases as the weight of the club head10increases and as the length of the club head10decreases.

FIGS. 8-9depict the interdependent relationship between discretionary weight, length of the golf club, swing weight, and total weight of the club head10through an exemplary set of golf clubs including drivers, fairway woods, hybrids, and irons. As illustrated inFIG. 8, the amount of discretionary weight, listed as discretionary mass, varies as swing weight (“SWT,” which generally is assigned a value from A0 (lightest) to F9 (heaviest), e.g. D0-D6) of the golf club, the length of the golf club (or “club length” measured in inches), and weight of the club head10(measured in grams) vary. It should be appreciated that the disclosed club lengths, head weights, swing weights, and discretionary weights are provided for purposes of illustration, and may include a range or band of club lengths, head weights, swing weights, and/or discretionary weights above and below the disclosed data points ofFIGS. 8-9.

Generally, club heads10are lighter in longer clubs to preserve swing weight in a range that does not hinder a golf swing. When the golf club has a swing weight that is too light, the performance of the club is reduced due to lower MOI of the club head and poor head center of gravity86placement. When the golf club has a swing weight that is too high, the club can be difficult to swing and deliver at impact.

Further referring toFIG. 8, discretionary weight is also provided for a group of example fairway woods having the same target swing weight of D1, but different club lengths from 43 inches (for a lower lofted 3-wood) to 41.5 inches (for a higher lofted 9-wood), and corresponding different head weights from 219 grams (for the 3-wood) to 232 grams (for the 9-wood). The discretionary weight ranges from greater than or equal to 59 grams, or approximately 26.9% of the total head weight (for the 3-wood) to greater than or equal to 72 grams, or approximately 31.0% of the total head weight (for the 9-wood). While the fairway woods described herein are exemplary fairway woods, the same relationship may apply to any fairway woods having a volume between approximately 115-300 cc, lofts between approximately 10-40 degrees, and club lengths between approximately 38-44 inches (97-112 cm).

Further referring toFIG. 8, discretionary weight is also provided for a group of example hybrids having the same target swing weight of D1, but different club lengths from 40.75 inches (103.5 cm) (for a lower lofted 2-hybrid) to 38.75 inches (98.4 cm) (for a higher lofted 6-hybrid), and corresponding different head weights from greater than or equal to 230 grams (for the 2-hybrid) to greater than or equal to 250 grams (for the 6-hybrid). The discretionary weight ranges from 90 grams, or approximately 39.1% of the total head weight (for the 2-hybrid) to 110 grams, or approximately 44.0% of the total head weight (for the 6-hybrid). While the hybrids described herein are exemplary hybrids, the same relationship may apply to any hybrid having a volume between approximately 80-140 cc, lofts between approximately 15-60 degrees, and club lengths between approximately 35-42 inches (89-107 cm).

Further referring toFIG. 8, discretionary weight is also provided for a group of example irons having the same target swing weight of D0, but different club lengths from 38.875 inches (98.7 cm) (for a lower lofted 4-iron) to 35 inches (88.69 cm) (for a higher lofted wedge), and corresponding different head weights from 239 grams (for the 4-iron) to 306 grams (for the wedge). The discretionary weight ranges from greater than or equal to 24 grams, or approximately 10.1% of the total head weight (for the 4-iron) to greater than or equal to 43 grams, or approximately 14.1% of the total head weight (for the wedge). While the irons described herein are exemplary irons, the same relationship may apply to any iron having lofts between approximately 15-60 degrees, and club lengths between approximately 35-42 inches (88.9-107 cm).

FIG. 9graphically depicts an exemplary relationship of club length (in inches) to total weight of the club head10(in grams) for a traditional target swing weight. By graphically depicting the data inFIG. 8, the interdependent relationship of head weight, club length, and swing weight (and in turn discretionary weight) for the exemplary golf clubs described herein is illustrated, as evidence by the high correlation of the data points to the coefficient of determination, which is denoted by an R squared value of 0.9818.

The weight member70, described herein, affects the head center of gravity86position and the MOI of the club head10about the y-axis510, the x-axis500, and/or the hosel axis36. Changing the head center of gravity86and the moment of inertia of the club head10about the y-axis510, the x-axis500, and/or the hosel axis36by positioning of the weight member70may change the performance characteristics of the golf club during a swing, at impact with a golf ball, or a combination of both (i.e. during a swing and at impact with the golf ball).

During a swing, the club head10rotates about the hosel axis36to square the face22at impact with the golf ball. Squaring the face22during a swing promotes the desired ball direction. At impact, the position of contact with the golf ball on the club face22, relative to the head center of gravity86position, affects the spin of the golf ball, or the gear effect. During flight, the golf ball spins or rotates about an axis. The axis of rotation of the golf ball can be broken down into components including a vertical axis perpendicular to a ground plane, and a horizontal axis parallel to a ground plane. The component of spin of the golf ball about the vertical axis affects ball direction. The component of spin of the golf ball about the horizontal axis affects trajectory and distance. The gear affect is described in further detail in the example below.

For example, impact of the golf ball on the club face22, offset from the head center of gravity86in the direction of the x-axis500, causes the club head10to rotate about the y-axis510in a first direction, thereby imparting a component of spin on the golf ball about the vertical axis in a second direction opposite the first direction. The component of spin of the golf ball about the vertical axis affects the fade or draw of the golf ball. Similarly, impact of the golf ball on the face22, offset from the head center of gravity86in the direction of the y-axis510, causes the club head10to rotate about the x-axis500in a third direction, thereby imparting a component of spin on the golf ball about the horizontal axis in a fourth direction opposite the third direction. The component of spin of the golf ball about the horizontal axis affects the trajectory and distance of the golf ball.

Typically, in golf club design, increased MOI of the club head10about the x-axis500and the y-axis510is desired. Increasing the MOI of the club head10about the x-axis500and/or the y-axis510results in increased resistance to rotation of the club head10about the x-axis500and/or the y-axis510, respectively, leading to reduced rotation of the club head and golf ball due to off center hits at impact. Increasing the MOI of the club head10about the x-axis500reduces the component of horizontal spin of the golf ball due to off center impact, thereby increasing forgiveness and consistency in ball trajectory and distance. Increasing the MOI of the club head10about the y-axis500reduces the component of vertical spin of the golf ball due to off center impact, thereby increasing forgiveness and consistency in ball direction. MOI of the club head10about an axis may be increased or maximized by increasing or maximizing the perpendicular distance between the weight member center of gravity86and the axis.

In the illustrated embodiment, shown inFIG. 4, the weight member70is positioned on the exterior side78of the crown30such that the distance between the weight member center of gravity88and the head center of gravity86is increased or maximized compared to a known club head with a weight member positioned closer to the head center of gravity. Specifically, the perpendicular distance between the weight member center of gravity88and the y-axis510(and therefore the MOI of the club head10about the y-axis510) is increased or maximized, and the perpendicular distance between the weight member center of gravity88and the x-axis500(and therefore the MOI of the club head10about the x-axis500) is increased or maximized compared to a known club head having a weight member positioned closer to the head center of gravity. Therefore, the club head10having the weight member70has increased or maximized directional forgiveness and consistency (due to the increased MOI of the club head about the y-axis) and increased or maximized consistency in trajectory and distance of the golf ball (due to the increased MOI of the club head about the x-axis).

The position of the weight member70on the club head10may also be used affect the MOI of the club head10about the hosel axis36. For example, the weight member center of gravity88may be positioned closer to the heel18or closer to the toe14of the club head10to create a heel or toe bias.

Positioning the weight member70such that the weight member center of gravity88is closer to the heel18than to the toe14(i.e. between the 6 o'clock and 9 o'clock positions) will shift the head center of gravity86toward the heel18and decrease the perpendicular distance from the head center of gravity86to the hosel axis36, thereby reducing the MOI of the club head10about the hosel axis36. Therefore, the club head10would have less resistance to rotation about the hosel axis36during a swing, allowing the user to more easily square the face22at impact to correct the tendency of a user to impact the golf ball with an open face22. Conversely, positioning the weight member70such that the weight member center of gravity88is closer to the toe14than to the heel18(i.e. between the 3 o'clock and 6 o'clock positions) will shift the head center of gravity86toward the toe14and increase the perpendicular distance from the weight member center of gravity86to the hosel axis36, thereby increasing the MOI of the club head10about the hosel axis36. Therefore, the club head10would have greater resistance to rotation about the hosel axis36during a swing to correct the tendency of a user to impact the golf ball with a closed face22.

Referring toFIG. 6, a proof of concept test was performed to demonstrate the increased MOI of the club head10having the weight member70about the y-axis510, leading to increased forgiveness of the club head10. The proof of concept demonstrates that the MOI of the club head10about the y-axis510increases as the weight member70position and/or position of the discretionary weight is moved away from the head center of gravity86of the club head10. To demonstrate this conclusion, discretionary weight was moved and repositioned in the form of weight members70at increasing distances d away from the head center of gravity86along concentric circles or bands102a-d. The MOI of the club head10about the y-axis510was calculated with no repositioning of discretionary weight on the crown30of the club head (a baseline). Then, the MOI of the club head10about the y-axis510was separately calculated for discretionary weight repositioned in the form of weight members70along bands102a,102b,102c, and102d, respectively. The MOI of the club head10about the y-axis510was significantly greater (up to approximately 50% greater) when discretionary weight was repositioned in the form of the weight member70along band102dthan when discretionary weight was not repositioned at all (the baseline, i.e. without the weight member70).

Referring toFIG. 13, the club head10having the weight member70demonstrated reduced scatter in golf ball landing location (as indicated by the elliptical trend lines), compared to a similar control club head without the weight member. The results illustrated inFIG. 13utilized exemplary fairway-wood type golf clubs with controlled swing conditions (e.g. swing speed and orientation). Reduced scatter in golf ball landing location of the club head10having the weight member70is a result of the increased MOI of the club head10.

In the illustrated embodiment, the position of the weight member70on the exterior side78of the crown30may result in aerodynamic benefits of the club head. For example, the position of the weight member70on the exterior side78of the crown30may result in reduced aerodynamic drag and therefore increased club head10speed. Increased club head10speed may result in greater golf ball travel distance.

In the illustrated embodiment, the weight member70is positioned on the exterior side78of the crown30, therefore the head center of gravity86is positioned closer to the crown30and the back26of the club head10than the head center of gravity86of the club head10without the weight member70. The shift in head center of gravity86toward the crown30of the club head10may impart additional, undesired backspin on the golf ball at impact, which can lead to a decrease in golf ball travel distance. In order to counteract the described effects, other known methods of reducing backspin on the golf ball at impact may be implemented. For example, reducing backspin on the golf ball may be accomplished by increasing surface roughness on the club face22. Generally, the additional forgiveness and consistency in direction and distance of the golf ball, resulting from the increased MOI of the club head10about the x-axis500and y-axis510, outweigh the undesired effects from the head center of gravity86position relative to the crown30of the club head10.

In the illustrated embodiment, the position of the weight member70on the exterior side78of the crown30may require balancing of additional discretionary weight or non-discretionary weight in alternative positions. For example, the internal or external structure of the club head10may be adjusted to balance the position of the weight member70on the exterior side78of the crown30by adding internal or external geometries, altering the material or geometry of the body12of the club head10, altering the material or geometry of the club face22, or any combination of the described alterations.

FIG. 11illustrates a method of manufacturing the club head10having the weight member70. The method includes providing the body12having the crown30, the sole34, the heel18, the toe14, the back end26, and the hosel38, providing the club face22, providing the weight member70, and forming or coupling the weight member70and the club face22to the club body12. In some embodiments, providing the body12includes casting or machining the body12. In other embodiments, the body12can be formed using any other suitable method, such as machining or 3D printing. In some embodiments, providing the club face22includes machining the club face22. In other embodiments, the club face22can be formed using any other suitable method, such as casting or 3D printing. In some embodiments, providing the weight member70can include casting, machining, 3D printing, or any other suitable method to form the weight member70.

The method of manufacturing the club head10described herein is merely exemplary and is not limited to the embodiments presented herein. The method can be employed in many different embodiments or examples not specifically depicted or described herein. In some embodiments, the processes of the method described can be performed in any suitable order. In other embodiments, one or more of the processes may be combined, separated, or skipped.

The weight member70may be formed at the same time as the body12during casting or the weight member70may be formed separately and coupled to the body12of the club head10. When the weight member70is be formed at the same time as the body12during casting, the added weight provided on the exterior side78of the crown30may increase the flow rate of molten material during the casting process to form the club head10having the weight member70.

As illustrated inFIG. 10, the club head10includes a first port or gate106at the toe side14, a second port or gate110at the heel side18, and a third port or gate114at the rear of the club head10. Each gate106,110,114allows for the introduction of molten material into the mold during casting to integrally form the weight member70to the crown30. The molten material flow direction is illustrated by arrows108,112, and116. The position of the weight member70on the crown30near the third gate114results in an increase in flow rate of the molten material through the casting mold due to the increased size in cross sectional area of the third gate114opening required to accommodate weight member70. The increase in molten material flow rate and/or the ability of the molten material to move more freely, assists the molten material in flowing to the crown30, the sole34, the heel18, and/or the toe14to reach relatively thin sections of the casting mold and to carry slag and/or particulates out of the club body12. It should be appreciated that in other embodiments, the weight member70may be attached or otherwise secured to the crown30as a separate component after casting of the crown30. Further, the weight member70may be formed at the same time as the body12using processes other than casting, such as, for example, metal injection molding (MIM), separate cast, forging, machining, printing, or rapid prototyping.

Clause 1: A golf club head comprising: a body having a crown defining a perimeter of the club head, a sole opposite the crown, a toe end opposite a heel end, a back end, and a hosel; a club face; an exterior side; an interior side; a head center of gravity; and a weight member positioned on one of the exterior side or the interior side of the crown, the weight member having a weight member center of gravity and an elongated arcuate shape along the crown.

Clause 2: The golf club head of clause 2, wherein the weight member is positioned on a side of an x-axis toward the back end, wherein the x-axis extends through the head center of gravity from the toe end to the heel end.

Clause 3: The golf club head of clause 1, wherein the weight member further includes at least one of (a) a width between approximately 0.25 and 1.5 inches, (b) a projection height between approximately 0.05 and 0.45 inches, (c) a length between approximately 2.5 and 5.5 inches, or (d) any combination thereof.

Clause 4: The golf club head of clause 1, wherein the weight member includes a plurality of weight members.

Clause 5: The golf club head of clause 4, wherein each weight member of the plurality of weight members extends along a portion of the perimeter defined by the crown.

Clause 6: The golf club head of clause 4, wherein the plurality of weight members includes at least one weight member positioned on the exterior side of the club head and at least one weight member positioned on the interior side of the club head.

Clause 7: The golf club head of clause 1, wherein the crown defines a crown surface curvature that extends from the club face to the back end, the weight member projecting from the crown surface curvature.

Clause 8: The golf club head of clause 1, wherein the crown and the weight member define a crown surface curvature having a bi-modal profile that extends from the club face to the back end.

Clause 9: The golf club head clause 1, wherein the crown and the weight member define a crown surface curvature having a bi-modal profile that extends from the club face to the back end at a portion of the perimeter defined by the crown.

Clause 10: The golf club head of clause 1, wherein the weight member is formed of discretionary weight.

Clause 11: The golf club head of clause 1, wherein the club head is a driver-type club head, a wood-type club head, or a hybrid-type club head.

Clause 12: The golf club head of clause 1, wherein the weight member has a weight ranging from approximately 15% to 55% of a total weight of the golf club head.

Clause 13: The golf club head of clause 11, wherein the weight member has a weight ranging from 15% to 35% of a total weight of the driver-type club head.

Clause 14: The golf club head of clause 11, wherein the weight member has a weight ranging from approximately 20% to 40% of a total weight of the wood-type club head.

Clause 15: The golf club head of clause 11, wherein the weight member has a weight ranging from approximately 25% to 55% of a total weight of the hybrid-type club head.

Clause 16: The golf club head of clause 1, wherein the weight member has a weight ranging from 20 grams to 130 grams.

Clause 17: The golf club head of clause 11, wherein the weight member has a weight ranging from 20 grams to 60 grams for the driver-type club head.

Clause 18: The golf club head of clause 11, wherein the weight member has a weight ranging from 45 grams to 85 grams for the wood-type club head.

Clause 19: The golf club head of clause 11, wherein the weight member has a weight ranging from 70 grams to 130 grams for the hybrid-type club head.

Clause 20: A golf club head comprising: a body having a crown defining a perimeter of the club head, a sole opposite the crown, a toe end opposite a heel end, a back end, and a hosel; a club face; an exterior side; an interior side; a head center of gravity; and a weight member positioned on one of the exterior side or the interior side of the crown, the weight member having a weight member center of gravity and a curved center line extending through the weight member center of gravity such that at any position along the perimeter, the curved center line is positioned at the same perpendicular distance from the crown; wherein a first distance from the head center of gravity to the curved center line at a particular position relative to the perimeter is greater than any second distance from the head center of gravity to the interior side or the exterior side of the club head on the crown or sole at the particular position relative to the perimeter.

As the rules to golf may change from time to time (e.g., new regulations may be adopted or old rules may be eliminated or modified by golf standard organizations and/or governing bodies such as the United States Golf Association (USGA), the Royal and Ancient Golf Club of St. Andrews (R&A), etc.), golf equipment related to the apparatus, methods, and articles of manufacture described herein may be conforming or non-conforming to the rules of golf at any particular time. Accordingly, golf equipment related to the apparatus, methods, and articles of manufacture described herein may be advertised, offered for sale, and/or sold as conforming or non-conforming golf equipment. The apparatus, methods, and articles of manufacture described herein are not limited in this regard.

While the above examples may be described in connection with a wood-type golf club, the apparatus, methods, and articles of manufacture described herein may be applicable to other types of golf club such as a fairway wood-type golf club, a hybrid-type golf club, an iron-type golf club, a wedge-type golf club, or a putter-type golf club. Alternatively, the apparatus, methods, and articles of manufacture described herein may be applicable other type of sports equipment such as a hockey stick, a tennis racket, a fishing pole, a ski pole, etc.