Aerodynamic golf club head
11045694 · 2021-06-29
Assignee
Inventors
- Kraig Alan Willett (Fallbrook, CA, US)
- Jeffrey J. Albertsen (Plano, TX, US)
- Michael Scott Burnett (McKinney, TX, US)
Cpc classification
A63B53/042
HUMAN NECESSITIES
A63B2225/01
HUMAN NECESSITIES
F15D1/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
A63B53/0408
HUMAN NECESSITIES
International classification
Abstract
An aerodynamic golf club head with a low center of gravity and producing reduced aerodynamic drag forces. The club head has crown section attributes and material attributes that impart beneficial aerodynamic properties and performance.
Claims
1. An aerodynamic golf club head comprising: A) a hollow body (110) having a club head volume of at least 400 cc, a face (200) formed of a metallic face material, a sole section (300), a crown section (400), a front (112), a back (114), a heel (116), a toe (118), and a front-to-back dimension (FB) of at least 4.4 inches, wherein i) the hollow body (110) has a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define an origin point; ii) the hollow body (110) has a center of gravity (CG) located: (a) vertically toward the crown section (400) from the origin point a distance Ycg in a direction orthogonal to the ground plane (GP), and vertically toward the crown section (400) from a horizontal center face plane a distance Vcg in a direction orthogonal to the horizontal center face plane, wherein the distance Vcg is less than or equal to 0 inches; (b) horizontally from the origin point toward the toe (118) a distance Xcg that is parallel to a vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); and (c) a distance Zcg from the origin toward the back (114) in a direction orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; and iii) the hollow body (110) includes a metallic body material that has a lower density than the metallic face material; B) the face (200) having a top edge (210) and a lower edge (220), wherein a top edge height (TEH) is the elevation of the top edge (210) above the ground plane (GP), and a lower edge height (LEH) is the elevation of the lower edge (220) above the ground plane (GP), wherein a portion of the top edge height (TEH) is at least 2 inches, and the face has a face thickness that varies from a maximum face thickness to a minimum face thickness, with the maximum face thickness is at least 25% greater than the minimum face thickness; and C) the crown section (400) having a crown apex (410) located an apex height (AH) above the ground plane (GP), and an apex plane (AP) passes through the crown apex (410) and is parallel to the ground plane (GP), wherein; i) the crown apex (410) is located behind the forwardmost point on the face (200) a distance that is a crown apex setback dimension (412) measured in a direction toward the back (114) and orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; ii) the crown apex (410) is located a distance from the origin toward the toe (118) a crown apex x-dimension (416) distance that is parallel to the vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); iii) the crown section (400) includes a post apex attachment promoting region (420) on the surface of the crown section (400) at an elevation above a maximum top edge plane (MTEP) wherein the post apex attachment promoting region (420) begins at the crown apex (410) and extends toward the back (114), and includes: (a) an attachment promoting region length (422) measured along the surface of the crown section (400) and orthogonal to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region length (422) is at least as great as fifty percent of the crown apex setback dimension (412); (b) an attachment promoting region width (424) measured along the surface of the crown section (400) in a direction parallel to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region width (424) is at least as great as the difference between the crown apex x-dimension (416) and the distance Xcg; and (c) wherein the post apex attachment promoting region (420) is located above a rotated apex plane, wherein the rotated apex plane is the apex plane (AP) rotated twenty degrees, downward toward the rear (114), about a line passing through the crown apex (410) and parallel to the vertical plane defined by the shaft axis (SA); iv) the crown section (400) has a 12 degree pitched up orientation crown apex (610) and defining a 12 degree pitched up/8 mm drop contour area (CA), wherein; (a) the 12 degree pitched up orientation crown apex (610) is located at a peak height of the crown section (400) when the hollow body is positioned in a 12 degree pitched up orientation that includes an absolute lie angle of 55 degrees, a face angle of 0 degrees, and a pitch angle of 12 degrees up; (b) the 12 degree/8 mm drop contour area (CA) is defined as the cross-sectional area of an intersection of the crown section (400) with an offset plane located at an elevation that is 8 mm below the 12 degree pitched up orientation crown apex (610) and parallel to the ground plane (GP) when the hollow body is positioned in the 12 degree pitched up orientation; and (c) wherein the hollow body (110) has a projected area of the face portion (A.sub.f), and wherein the 12 degree pitched up/8 mm drop contour area (CA) is greater than the linear expression:
CA=−1.5395*A.sub.f+19.127 v) less than 10% of the club head volume is located above the maximum top edge plane (MTEP); and vi) a portion of the crown section (400) at an elevation above the maximum top edge plane (MTEP) has an apex-to-front radius of curvature (Ra-f), an apex-to-rear radius of curvature (Ra-r), and a heel-to-toe radius of curvature (Rh-t), wherein at least a portion of the apex-to-rear radius of curvature (Ra-r) is greater than 5 inches; D) the golf club head includes an adjustable loft system.
2. The aerodynamic golf club head of claim 1, wherein the metallic body material is an aluminum alloy, the attachment promoting region length (422) is at least as great as 75% of the crown apex setback dimension (412), and the attachment promoting region width (424) is at least twice as the difference between the crown apex x-dimension (416) and the distance Xcg.
3. The aerodynamic golf club head of claim 2, wherein the aluminum alloy metallic body material includes a rearwardmost point on the hollow body (110).
4. The aerodynamic golf club head of claim 3, further including at least one weight attached to the aluminum alloy metallic body material.
5. The aerodynamic golf club head of claim 1, wherein the post apex attachment promoting region (420) is composed of nonmetallic material, the attachment promoting region length (422) is at least as great as 75% of the crown apex setback dimension (412), the attachment promoting region width (424) is at least fifty percent of a crown apex-to-toe dimension (418) measured from the crown apex (410) to the toewardmost point on the hollow body (110), and the projected area of the face portion (Af) is at least 8.3 square inches.
6. The aerodynamic golf club head of claim 1, wherein the crown apex setback dimension (412) is at least 10% of the front-to-back dimension (FB) and less than 1.75 inches, and the crown apex setback dimension (412) is less than a distance from a vertical projection of the center of gravity (CG) on the ground plane (GP) to a second vertical projection of the forwardmost point on the face (200) on the ground plane (GP), the distance Vcg is less than or equal to −0.08 inches, and an apex ratio of the apex height (AH) to the greatest top edge height (TEH) is at least 1.13.
7. The aerodynamic golf club head of claim 1, wherein a portion of the top edge height (TEH) is at least 2.15 inches, and the 12 degree pitched up/8 mm drop contour area (CA) is greater than the following linear expression:
CA=1.5395*A.sub.f+19.627.
8. An aerodynamic golf club head comprising: A) a hollow body (110) having a club head volume of at least 400 cc, a face (200), a sole section (300), a crown section (400), a front (112), a back (114), a heel (116), a toe (118), and a front-to-back dimension (FB) of at least 4.4 inches, wherein i) the hollow body (110) has a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define an origin point; and ii) the hollow body (110) has a center of gravity (CG) located: (a) vertically toward the crown section (400) from the origin point a distance Ycg in a direction orthogonal to the ground plane (GP), and vertically toward the crown section (400) from a horizontal center face plane a distance Vcg in a direction orthogonal to the horizontal center face plane, wherein the distance Vcg is less than or equal to 0 inches; (b) horizontally from the origin point toward the toe (118) a distance Xcg that is parallel to a vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); and (c) a distance Zcg from the origin toward the back (114) in a direction orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; B) the face (200) having a top edge (210) and a lower edge (220), wherein a top edge height (TEH) is the elevation of the top edge (210) above the ground plane (GP), and a lower edge height (LEH) is the elevation of the lower edge (220) above the ground plane (GP), wherein a portion of the top edge height (TEH) is at least 2 inches; and C) the crown section (400) having a crown apex (410) located an apex height (AH) above the ground plane (GP), wherein; i) the crown apex (410) is located behind the forwardmost point on the face (200) a distance that is a crown apex setback dimension (412) measured in a direction toward the back (114) and orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; ii) the crown apex (410) is located a distance from the origin toward the toe (118) a crown apex x-dimension (416) distance that is parallel to the vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); iii) the crown section (400) includes a post apex attachment promoting region (420) on the surface of the crown section (400) at an elevation above a maximum top edge plane (MTEP) wherein the post apex attachment promoting region (420) begins at the crown apex (410) and extends toward the back (114), and includes: (a) an attachment promoting region length (422) measured along the surface of the crown section (400) and orthogonal to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region length (422) is at least as great as fifty percent of the crown apex setback dimension (412); (b) an attachment promoting region width (424) measured along the surface of the crown section (400) in a direction parallel to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region width (424) is at least as great as the difference between the crown apex x-dimension (416) and the distance Xcg; and (c) wherein the post apex attachment promoting region (420) is located above a rotated apex plane, wherein the rotated apex plane is the apex plane (AP) rotated twenty degrees, downward toward the rear (114), about a line passing through the crown apex (410) and parallel to the vertical plane defined by the shaft axis (SA); iii) a portion of the crown section (400) at an elevation above the maximum top edge plane (MTEP) has at least one of: (a) a portion of the crown section (400) between the crown apex (410) and the back (114) of the hollow body (110) has an apex-to-rear radius of curvature (Ra-r), wherein at least a portion of the apex-to-rear radius of curvature (Ra-r) is greater than 5 inches; or (b) a portion of the crown section (400) has a heel-to-toe radius of curvature (Rh-t), wherein the portion of the heel-to-toe radius of curvature (Rh-t) in contact with the crown apex (410) is less than 4 inches; iv) the crown section (400) having a 12 degree pitched up orientation crown apex (610) and defining a 12 degree pitched up/8 mm drop contour area (CA), wherein; (a) the 12 degree pitched up orientation crown apex (610) is located at a peak height of the crown section (400) when the hollow body is positioned in a 12 degree pitched up orientation that includes an absolute lie angle of 55 degrees, a face angle of 0 degrees, and a pitch angle of 12 degrees up; (b) the 12 degree/8 mm drop contour area (CA) is defined as the cross-sectional area of an intersection of the crown section (400) with an offset plane located at an elevation that is 8 mm below the 12 degree pitched up orientation crown apex (610) and parallel to the ground plane (GP) when the hollow body is positioned in the 12 degree pitched up orientation; and (c) wherein the hollow body (110) has a projected area of the face portion (A.sub.f), and wherein the 12 degree pitched up/8 mm drop contour area (CA) is greater than the linear expression:
CA=−1.5395*A.sub.f+19.127 D) wherein a rearwardmost point on the hollow body (110) is located at a rearward most point elevation (523) that is greater than the distance Ycg.
9. The aerodynamic golf club head of claim 8, wherein a portion of the hollow body (110) including the rearwardmost point is formed of an aluminum alloy, the face has a face thickness that varies from a maximum face thickness to a minimum face thickness, and a first moment of inertia (MOIy) about a vertical axis through the center of gravity (CG) is at least 4000 g*cm.sup.2, a second moment of inertia (MOIx) about a horizontal axis through the center of gravity (CG) is at least 2000 g*cm.sup.2, the attachment promoting region length (422) is at least as great as 75% of the crown apex setback dimension (412), and the attachment promoting region width (424) is at least twice as the difference between the crown apex x-dimension (416) and the distance Xcg.
10. The aerodynamic golf club head of claim 9, wherein the post apex attachment promoting region (420) is composed of nonmetallic material, and the projected area of the face portion (A.sub.f) is at least 8.3 square inches.
11. The aerodynamic golf club head of claim 8, wherein hollow body (110) includes a skirt (500) connecting a portion of the crown section (400) to a portion of the sole section (300), a portion of the skirt (500) having a skirt profile (550) that is concave within a profile region angle (552) of 45 degrees originating at the crown apex (410), the concave skirt profile (550) creating (a) a skirt-to-sole transition region (510) at the connection to the sole section (300) and (b) a skirt-to-crown transition region (520) at the connection to the crown section (400), the skirt-to-sole transition region (510) having a rearwardmost SSTR point (512) at a rearwardmost SSTR point elevation (513), the skirt-to-crown transition region (520) having a rearwardmost SCTR point (522) at a rearwardmost SCTR point elevation (523), wherein a front-to-back horizontal separation distance (540) separates the rearwardmost SSTR point (512) and the rearwardmost SCTR point (522), and the front-to-back horizontal separation distance (540) is at least 30 percent of the difference between the apex height (AH) and the maximum top edge height (TEH), and the distance Vcg is less than or equal to −0.08 inches.
12. The aerodynamic golf club head of claim 11, wherein the rearwardmost SSTR point (512) and the rearwardmost SCTR point (522) are vertically separated by a vertical separation distance (530) that is at least 30 percent of the apex height (AH).
13. The aerodynamic golf club head of claim 11, wherein at least one of the rearwardmost SSTR point (512) and the rearwardmost SCTR point (522) are located between the center of gravity and the toe (118).
14. The aerodynamic golf club head of claim 8, wherein an apex ratio of the apex height (AH) to the greatest top edge height (TEH) is at least 1.13, and the 12 degree pitched up/8 mm drop contour area (CA) is greater than the following linear expression:
CA=−1.5395* A.sub.f+19.627.
15. An aerodynamic golf club head comprising: A) a hollow body (110) having a club head volume of at least 400 cc, a face (200), a sole section (300), a crown section (400), a front (112), a back (114), a heel (116), a toe (118), and a front-to-back dimension (FB) of at least 4.4 inches, wherein i) the hollow body (110) has a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define an origin point; and ii) the hollow body (110) has a center of gravity (CG) located: (a) vertically toward the crown section (400) from the origin point a distance Ycg in a direction orthogonal to the ground plane (GP), and vertically toward the crown section (400) from a horizontal center face plane a distance Vcg in a direction orthogonal to the horizontal center face plane, wherein the distance Vcg is less than or equal to 0 inches; (b) horizontally from the origin point toward the toe (118) a distance Xcg that is parallel to a vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); and (c) a distance Zcg from the origin toward the back (114) in a direction orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; B) the face (200) having a top edge (210) and a lower edge (220), wherein a top edge height (TEH) is the elevation of the top edge (210) above the ground plane (GP), and a lower edge height (LEH) is the elevation of the lower edge (220) above the ground plane (GP), wherein a portion of the top edge height (TEH) is at least 2 inches; and C) the crown section (400) having a crown apex (410) located an apex height (AH) above the ground plane (GP), wherein; i) the crown apex (410) is located behind the forwardmost point on the face (200) a distance that is a crown apex setback dimension (412) measured in a direction toward the back (114) and orthogonal to the vertical direction used to measure Ycg and orthogonal to the horizontal direction used to measure Xcg; ii) the crown apex (410) is located a distance from the origin toward the toe (118) a crown apex x-dimension (416) distance that is parallel to the vertical plane defined by the shaft axis (SA) and parallel to the ground plane (GP); iii) the crown section (400) includes a post apex attachment promoting region (420) on the surface of the crown section (400) at an elevation above a maximum top edge plane (MTEP) wherein the post apex attachment promoting region (420) begins at the crown apex (410) and extends toward the back (114), and includes: (a) an attachment promoting region length (422) measured along the surface of the crown section (400) and orthogonal to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region length (422) is at least as great as fifty percent of the crown apex setback dimension (412); (b) an attachment promoting region width (424) measured along the surface of the crown section (400) in a direction parallel to the vertical plane defined by the shaft axis (SA), wherein the attachment promoting region width (424) is at least as great as the difference between the crown apex x-dimension (416) and the distance Xcg; and (c) wherein the post apex attachment promoting region (420) is located above a rotated apex plane, wherein the rotated apex plane is the apex plane (AP) rotated twenty degrees, downward toward the rear (114), about a line passing through the crown apex (410) and parallel to the vertical plane defined by the shaft axis (SA); iv) the crown section (400) having a 12 degree pitched up orientation crown apex (610) and defining a 12 degree pitched up/8 mm drop contour area (CA), wherein; (a) the 12 degree pitched up orientation crown apex (610) is located at a peak height of the crown section (400) when the hollow body is positioned in a 12 degree pitched up orientation that includes an absolute lie angle of 55 degrees, a face angle of 0 degrees, and a pitch angle of 12 degrees up; (b) the 12 degree/8 mm drop contour area (CA) is defined as the cross-sectional area of an intersection of the crown section (400) with an offset plane located at an elevation that is 8 mm below the 12 degree pitched up orientation crown apex (610) and parallel to the ground plane (GP) when the hollow body is positioned in the 12 degree pitched up orientation; and (c) wherein the hollow body (110) has a projected area of the face portion (A.sub.f), and wherein the 12 degree pitched up/8 mm drop contour area (CA) is greater than the linear expression:
CA=−1.5395*A.sub.f+19.127 D) wherein a rearwardmost point on the hollow body (110) is located at a rearward most point elevation (523) that is greater than the distance Ycg; and E) wherein hollow body (110) includes a skirt (500) connecting a portion of the crown section (400) to a portion of the sole section (300), a portion of the skirt (500) having a skirt profile (550), within a profile region angle (552) of 45 degrees originating at the crown apex (410), that creates (a) a skirt-to-sole transition region (510) at the connection to the sole section (300) and (b) a skirt-to-crown transition region (520) at the connection to the crown section (400), the skirt-to-sole transition region (510) having a rearwardmost SSTR point (512) at a rearwardmost SSTR point elevation (513), the skirt-to-crown transition region (520) having a rearwardmost SCTR point (522) at a rearwardmost SCTR point elevation (523), wherein a front-to-back horizontal separation distance (540) separates the rearwardmost SSTR point (512) and the rearwardmost SCTR point (522), and the front-to-back horizontal separation distance (540) is at least 30 percent of the difference between the apex height (AH) and the maximum top edge height (TEH).
16. The aerodynamic golf club head of claim 15, wherein a first portion of the hollow body (110) is formed of a titanium alloy and the face is a fiber composite material face insert adhesively attached to the first portion, and a first moment of inertia (MOIy) about a vertical axis through the center of gravity (CG) is at least 4000 g*cm.sup.2, a second moment of inertia (MOIx) about a horizontal axis through the center of gravity (CG) is at least 2000 g*cm.sup.2, the attachment promoting region length (422) is at least as great as 75% of the crown apex setback dimension (412), and the attachment promoting region width (424) is at least twice as the difference between the crown apex x-dimension (416) and the distance Xcg.
17. The aerodynamic golf club head of claim 16, wherein a second portion of the hollow body (110) is formed of a polymeric material and includes the rearwardmost point, and the post apex attachment promoting region (420) is composed of nonmetallic material.
18. The aerodynamic golf club head of claim 15, wherein a first moment of inertia (MOIy) about a vertical axis through the center of gravity (CG) is at least 4000 g*cm.sup.2, and a second moment of inertia (MOIx) about a horizontal axis through the center of gravity (CG) is at least 2000 g*cm.sup.2, and a rearwardmost point on the hollow body (110) is formed of an aluminum alloy.
19. The aerodynamic golf club head of claim 18, further including at least one weight attached to the aluminum alloy metallic body material.
20. The aerodynamic golf club head of claim 17, wherein the crown apex setback dimension (412) is at least 10% of the front-to-back dimension (FB) and less than 1.75 inches, and the crown apex setback dimension (412) is less than a distance from a vertical projection of the center of gravity (CG) on the ground plane (GP) to a second vertical projection of the forwardmost point on the face (200) on the ground plane (GP), and the distance Vcg is less than or equal to −0.08 inches, and the 12 degree pitched up/8 mm drop contour area (CA) is greater than the following linear expression:
CA=−1.5395*A.sub.f+19.627.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Without limiting the scope of the present aerodynamic golf club head as claimed below and referring now to the drawings and figures:
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40) These drawings are provided to assist in the understanding of the exemplary embodiments of the high volume aerodynamic golf club head as described in more detail below and should not be construed as unduly limiting the present golf club head. In particular, the relative spacing, positioning, sizing and dimensions of the various elements illustrated in the drawings are not drawn to scale and may have been exaggerated, reduced or otherwise modified for the purpose of improved clarity. Those of ordinary skill in the art will also appreciate that a range of alternative configurations have been omitted simply to improve the clarity and reduce the number of drawings.
DETAILED DESCRIPTION OF THE INVENTION
(41) The claimed high volume aerodynamic golf club head (100) enables a significant advance in the state of the art. The preferred embodiments of the club head (100) accomplish this by new and novel arrangements of elements and methods that are configured in unique and novel ways and which demonstrate previously unavailable but preferred and desirable capabilities. The description set forth below in connection with the drawings is intended merely as a description of the presently preferred embodiments of the club head (100), and is not intended to represent the only form in which the club head (100) may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the club head (100) in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and features may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the club head (100).
(42) The present high volume aerodynamic golf club head (100) has recognized that the poor aerodynamic performance of large FB dimension drivers is not due solely to the large FB dimension; rather, in an effort to create large FB dimension drivers with a high MOIy value and low center of gravity (CG) dimension, golf club designers have generally created clubs that have very poor aerodynamic shaping. The main problems are the significantly flat surfaces on the body, the lack of proper shaping to account for airflow reattachment in the crown area trailing the face, and the lack of proper trailing edge design. In addition, current large FB dimension driver designs have ignored, or even tried to maximize in some cases, the frontal cross sectional area of the golf club head which increases the aerodynamic drag force. The present aerodynamic golf club head (100) solves these issues and results in a high volume aerodynamic golf club head (100) having a large FB dimension and a high MOIy.
(43) The present high volume aerodynamic golf club head (100) has a volume of at least 400 cc. It is characterized by a face-on normalized aerodynamic drag force of less than 1.5 lbf when exposed to a 100 mph wind parallel to the ground plane (GP) when the high volume aerodynamic golf club head (100) is positioned in a design orientation and the wind is oriented at the front (112) of the high volume aerodynamic golf club head (100), as previously described with respect to
(44) With general reference to
(45) The relatively large FB dimension of the present high volume aerodynamic golf club head (100) aids in obtaining beneficial moment of inertia values while also obtaining superior aerodynamic properties unseen by other large volume, large FB dimension, high MOI golf club heads. Specifically, an embodiment of the high volume aerodynamic golf club head (100) obtains a first moment of inertia (MOIy) about a vertical axis through a center of gravity (CG) of the golf club head (100), illustrated in
(46) The golf club head (100) obtains superior aerodynamic performance through the use of unique club head shapes. Referring now to
(47) The center of the face (200) shall be determined in accordance with the USGA “Procedure for Measuring the Flexibility of a Golf Clubhead,” Revision 2.0, Mar. 25, 2005, which is incorporated herein by reference. This USGA procedure identifies a process for determining the impact location on the face of a golf club that is to be tested, also referred therein as the face center. The USGA procedure utilizes a template that is placed on the face of the golf club to determine the face center.
(48) Secondly, a portion of the crown section (400) between the crown apex (410) and the back (114) of the hollow body (110) has an apex-to-rear radius of curvature (Ra-r) that is less than 3.75 inches. The apex-to-rear radius of curvature (Ra-r) is also measured in a vertical plane that is perpendicular to a vertical plane passing through the shaft axis (SA), and the apex-to-rear radius of curvature (Ra-r) is further measured at the point on the crown section (400) between the crown apex (410) and the back (114) that has the smallest the radius of curvature. In one particular embodiment, at least fifty percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches. In still a further embodiment, at least ninety percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches. In yet another embodiment, one hundred percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which intersect a portion of the face top edge (210) between the center of the face (200) and the toeward most point on the face (200), are characterized by an apex-to-rear radius of curvature (Ra-r) of less than 3.75 inches.
(49) Lastly, as seen in
(50) Such small radii of curvature exhibited in the embodiments described herein have traditionally been avoided in the design of high volume golf club heads, especially in the design of high volume golf club heads having FB dimensions of 4.4 inches and greater. However, it is these tight radii produce a bulbous crown section (400) that facilitates airflow reattachment as close to the face (200) as possible, thereby resulting in reduced aerodynamic drag forces and facilitating higher club head speeds.
(51) Conventional high volume large MOIy golf club heads having large FB dimensions, such as those seen in U.S. Pat. No. D544,939 and U.S. Pat. No. D543,600, have relatively flat crown sections that often never extend above the face. While these designs appear as though they should cut through the air, the opposite is often true with such shapes achieving poor airflow reattachment characteristics and increased aerodynamic drag forces. The present club head (100) has recognized the significance of proper club head shaping to account for rapid airflow reattachment in the crown section (400) trailing the face (200), which is quite the opposite of the flat steeply sloped crown sections of many prior art large FB dimension club heads.
(52) With reference now to
(53) The top edge (210) and lower edge (220) are identifiable as curves that mark a transition from the curvature of the face (200) to adjoining regions of the club head (100), such as the crown section (400), the sole section (300), or a transition region (230) between the face (200) and the crown section (400) or sole section (300) (see, e.g.,
(54) One of many significant advances of this embodiment of the present club head (100) is the design of an apex ratio that encourages airflow reattachment on the crown section (400) of the golf club head (100) as close to the face (200) as possible. In other words, the sooner that airflow reattachment is achieved, the better the aerodynamic performance and the smaller the aerodynamic drag force. The apex ratio is the ratio of apex height (AH) to the maximum top edge height (TEH). As previously explained, in many large FB dimension golf club heads the apex height (AH) is no more than the top edge height (TEH). In this embodiment, the apex ratio is at least 1.13, thereby encouraging airflow reattachment as soon as possible.
(55) Still further, this embodiment of the club head (100) has a frontal cross sectional area that is less than 11 square inches. The frontal cross sectional area is the single plane area measured in a vertical plane bounded by the outline of the golf club head (100) when it is resting on the ground plane (GP) at the design lie angle and viewed from directly in front of the face (200). The frontal cross sectional area is illustrated by the cross-hatched area of
(56) In a further embodiment, a second aerodynamic drag force is introduced, namely the 30 degree offset aerodynamic drag force, as previously explained with reference to
(57) Yet another embodiment introduces a third aerodynamic drag force, namely the heel normalized aerodynamic drag force, as previously explained with reference to
(58) A still further embodiment has recognized that having the apex-to-front radius of curvature (Ra-f) at least 25% less than the apex-to-rear radius of curvature (Ra-r) produces a particularly aerodynamic golf club head (100) further assisting in airflow reattachment and preferred airflow attachment over the crown section (400). Yet another embodiment further encourages quick airflow reattachment by incorporating an apex ratio of the apex height (AH) to the maximum top edge height (TEH) that is at least 1.2. This concept is taken even further in yet another embodiment in which the apex ratio of the apex height (AH) to the maximum top edge height (TEH) is at least 1.25. Again, these large apex ratios produce a bulbous crown section (400) that facilitates airflow reattachment as close to the face (200) as possible, thereby resulting in reduced aerodynamic drag forces and resulting in higher club head speeds.
(59) Reducing aerodynamic drag by encouraging airflow reattachment, or conversely discouraging extended lengths of airflow separation, may be further obtained in yet another embodiment in which the apex-to-front radius of curvature (Ra-f) is less than the apex-to-rear radius of curvature (Ra-r), and the apex-to-rear radius of curvature (Ra-r) is less than the heel-to-toe radius of curvature (Rh-t). Such a shape is contrary to conventional high volume, long FB dimension golf club heads, yet produces a particularly aerodynamic shape.
(60) Taking this embodiment a step further in another embodiment, a high volume aerodynamic golf club head (100) having the apex-to-front radius of curvature (Ra-f) less than 2.85 inches and the heel-to-toe radius of curvature (Rh-t) less than 3.85 inches produces a reduced face-on aerodynamic drag force. Another embodiment focuses on the playability of the high volume aerodynamic golf club head (100) by having a maximum top edge height (TEH) that is at least 2 inches, thereby ensuring that the face area is not reduced to an unforgiving level. Even further, another embodiment incorporates a maximum top edge height (TEH) that is at least 2.15 inches, further instilling confidence in the golfer that they are not swinging a golf club head (100) with a small striking face (200).
(61) The foregoing embodiments may be utilized having even larger FB dimensions. For example, the previously described aerodynamic attributes may be incorporated into an embodiment having a front-to-back dimension (FB) that is at least 4.6 inches, or even further a front-to-back dimension (FB) that is at least 4.75 inches. These embodiments allow the high volume aerodynamic golf club head (100) to obtain even higher MOIy values without reducing club head speed due to excessive aerodynamic drag forces.
(62) Yet a further embodiment balances all of the radii of curvature requirements to obtain a high volume aerodynamic golf club head (100) while minimizing the risk of an unnatural appearing golf club head by ensuring that less than 10% of the club head volume is above the elevation of the maximum top edge height (TEH). A further embodiment accomplishes the goals herein with a golf club head (100) having between 5% to 10% of the club head volume located above the elevation of the maximum top edge height (TEH). This range achieves the desired crown apex (410) and radii of curvature to ensure desirable aerodynamic drag while maintaining an aesthetically pleasing look of the golf club head (100).
(63) The location of the crown apex (410) is dictated to a degree by the apex-to-front radius of curvature (Ra-f); however, yet a further embodiment identifies that the crown apex (410) should be behind the forwardmost point on the face (200) a distance that is a crown apex setback dimension (412), seen in
(64) Additionally, the heel-to-toe location of the crown apex (410) also plays a significant role in the aerodynamic drag force. The location of the crown apex (410) in the heel-to-toe direction is identified by the crown apex ht dimension (414), as seen in
(65) The present high volume aerodynamic golf club head (100) has a club head volume of at least 400 cc. Further embodiments incorporate the various features of the above described embodiments and increase the club head volume to at least 440 cc, or even further to the current USGA limit of 460 cc. However, one skilled in the art will appreciate that the specified radii and aerodynamic drag requirements are not limited to these club head sizes and apply to even larger club head volumes. Likewise, a heel-to-toe (HT) dimension of the present club head (100), as seen in
(66) As one skilled in the art understands, the hollow body (110) has a center of gravity (CG). The location of the center of gravity (CG) is described with reference to an origin point, seen in
(67) Several more embodiments, seen in
(68) As with the prior embodiments, the embodiments containing the post apex attachment promoting region (420) include a maximum top edge height (TEH) of at least 2 inches and an apex ratio of the apex height (AH) to the maximum top edge height (TEH) of at least 1.13. As seen in
(69) In this particular embodiment, the crown section (400) includes a post apex attachment promoting region (420) on the surface of the crown section (400). Many of the previously described embodiments incorporate characteristics of the crown section (400) located between the crown apex (410) and the face (200) that promote airflow attachment to the club head (100) thereby reducing aerodynamic drag. The post apex attachment promoting region (420) is also aimed at reducing aerodynamic drag by encouraging the airflow passing over the crown section (400) to stay attached to the club head (100); however, the post apex attachment promoting region (420) is located between the crown apex (410) and the back (114) of the club head (100), while also being above the maximum top edge height (TEH), and thus above the maximum top edge plane (MTEP).
(70) Many conventional high volume, large MOIy golf club heads having large FB dimensions have crown sections that often never extend above the face. Further, these prior clubs often have crown sections that aggressively slope down to the sole section. While these designs appear as though they should cut through the air, the opposite is often true with such shapes achieving poor airflow reattachment characteristics and increased aerodynamic drag forces. The present club head (100) has recognized the significance of proper club head shaping to account for rapid airflow reattachment in the crown section (400) trailing the face (200) via the apex ratio, as well as encouraging the to airflow remain attached to the club head (100) behind the crown apex (410) via the apex ratio and the post apex attachment promoting region (420).
(71) With reference to
(72) While the post apex attachment promoting region (420) has both a length (422) and a width (424), the post apex attachment promoting region (420) need not be rectangular in nature. For instance,
(73) Like the previous embodiments having aerodynamic characteristics in front of the crown apex (410), the present embodiment incorporating the post apex attachment promoting region (420) located behind the crown apex (410) also has a face-on normalized aerodynamic drag force of less than 1.5 lbf when exposed to a 100 mph wind parallel to the ground plane (GP) when the high volume aerodynamic golf club head having a post apex attachment promoting region (100) is positioned in a design orientation and the wind is oriented at the front (112) of the high volume aerodynamic golf club head having a post apex attachment promoting region (100), as previously explained in detail.
(74) In a further embodiment, a second aerodynamic drag force is introduced, namely the 30 degree offset aerodynamic drag force, as previously explained with reference to
(75) Yet another embodiment introduces a third aerodynamic drag force, namely the heel normalized aerodynamic drag force, as previously explained with reference to
(76) Just as the embodiments that don't incorporate a post apex attachment promoting region (420) benefit from a relatively high apex ratio of the apex height (AH) to the maximum top edge height (TEH), so to do the embodiments incorporating a post apex attachment promoting region (420). After all, by definition the post apex attachment promoting region (420) is located above the maximum top edge plane (MTEP), which means that if the apex ratio is less than 1 then there can be no post apex attachment promoting region (420). An apex ratio of at least 1.13 provides for the height of the crown apex (410) that enables the incorporation of the post apex attachment promoting region (420) to reduce aerodynamic drag forces. Yet another embodiment further encourages airflow attachment behind the crown apex (410) by incorporating an apex ratio that is at least 1.2, thereby further increasing the available area on the crown section (400) above the maximum top edge height (TEH) suitable for a post apex attachment promoting region (420). The greater the amount of crown section (400) behind the crown apex (410), but above the maximum top edge height (TEH), and having the claimed attributes of the post apex attachment promoting region (420); the more likely the airflow is to remain attached to the club head (100) as it flows past the crown apex (410) and reduce the aerodynamic drag force.
(77) With reference to
(78) In a further embodiment seen in
(79) Yet another embodiment focuses not solely on the size of the post apex attachment promoting region (420), but also on the location of it. It is helpful to define a new dimension to further characterize the placement of the post apex attachment promoting region (420); namely, as seen in
(80) Another embodiment builds upon the post apex attachment promoting region (420) by having at least 7.5 percent of the club head volume located above the maximum top edge plane (MTEP), illustrated in
(81) As previously mentioned, in order to facilitate the post apex attachment promoting region (420), at least a portion of the crown section (400) has to be relatively flat and not aggressively sloped from the crown apex (410) toward the ground plane (GP). In fact, in one embodiment, a portion of the post apex attachment promoting region (420) has an apex-to-rear radius of curvature (Ra-r), seen in
(82) Further embodiments incorporate a post apex attachment promoting region (420) in which a majority of the cross sections taken from the face (200) to the back (114) of the club head (100), perpendicular to the vertical plane through the shaft axis (SA), which pass through the post apex attachment promoting region (420), have an apex-to-rear radius of curvature (Ra-r) that is greater than 5 inches. In fact, in one particular embodiment, at least seventy five percent of the vertical plane cross sections taken perpendicular to a vertical plane passing through the shaft axis (SA), which pass through the post apex attachment promoting region (420), are characterized by an apex-to-rear radius of curvature (Ra-r) that is greater than 5 inches within the post apex attachment promoting region (420); thereby further promoting airflow attachment between the crown apex (410) and the back (114) of the club head (100).
(83) Another embodiment incorporates features that promote airflow attachment both in front of the crown apex (410) and behind the crown apex (410). In this embodiment, seen in
(84) The attributes of the claimed crown section (400) tend to keep the crown section (400) distant from the sole section (300). One embodiment, seen in
(85) In this particular embodiment the rearwardmost SSTR point (512) and the rearwardmost SCTR point (522) need not be located vertically in-line with one another, however they are both located within the profile region angle (552) of
(86) In a further embodiment, illustrated best in
(87) Another embodiment advancing this principle has the rearwardmost SSTR point (512) is located on the heel (116) side of the center of gravity, and the rearwardmost SCTR point (522) is located on the toe (118) side of the center of gravity, as seen in
(88) Several more high volume aerodynamic golf club head embodiments, seen in and described by reference to
(89) As discussed above, the present high volume aerodynamic golf club heads have a face (200) that is intended to hit the golf ball. In a transition zone (230) of a club head the face (200) transitions to the external contour of the body (110), as shown in
(90) For consideration of the high volume aerodynamic golf club heads seen in and described in relation to
(91) As noted above, the face center (660) of the face (200) is determined in accordance with the USGA “Procedure for Measuring the Flexibility of a Golf Clubhead,” Revision 2.0, Mar. 25, 2005, which is incorporated herein by reference. A typical face center (660) is shown in
(92) The club head desirably is cut first along the offset bulge radius cut plane (664) (
(93) To determine the projected area of the face portion A.sub.f, and turning now to
A.sub.f=P.sub.f*(A.sub.r/P.sub.r)
wherein A.sub.f is the projected area of the face portion, P.sub.f is the pixel count in the face portion (670), A.sub.r is the area of the reference portion (672), and P.sub.r is the pixel count in the reference portion (672). In the example, if A.sub.r=7.77 in.sup.2, P.sub.f=298,890 pixels, and P.sub.r=259,150 pixels, then A.sub.f=9.14 in.sup.2.
(94) It will be understood that the pixel-counting technique described above is an example of a technique capable of measuring area accurately and precisely. Other area-measurement techniques can be employed in alternative methods
(95) In various embodiments, the projected area of the face portion A.sub.f is generally greater than 8.3 in.sup.2, desirably in the range of 8.3 to 15.5 in.sup.2, more desirably in the range of 9.0 to 12.5 in.sup.2, and most desirably in the range of 9.5 to 10.5 in.sup.2.
(96) The golf club head (100) embodiments shown in and described in relation to
(97) Using the foregoing methods for measuring projected area of the face portion (A.sub.f) and the 8 mm drop contour area (CA), swing path data was investigated for a number of example golf clubs. For a given golf club head orientation, the drag force of the club head moving through air can be calculated according to the following equation:
Drag Force=0.5*ρ*u.sup.2*Cd*A
where ρ is the air density, u is the airspeed of the club head, Cd is the drag coefficient, and A is the projected area of the golf club head. Resolving the equation for the product Cd*A provides the following:
Cd*A=Drag Force/0.5*ρ*u.sup.2
Through swing path analysis, it was found that the range along the swing path between 6 degree and 12 degree pitched up orientations of the golf club head were the most important for contributing to club head aerodynamics because it is within this range of club head orientation that the club head aerodynamic performance will have the most impact on club head speed. A drag force for the number of example golf clubs described above was measured experimentally under known conditions of air speed and air density. Values for the product of Cd*A were then determined for the golf club heads. These results were then plotted against the measured 8 mm drop contour area for the golf club heads in the 6 degree pitched up orientation. The results are provided in the graph shown in
(98) Turning next to
(99) In particular, as shown in
CA=−1.5395*A.sub.f+19.127 Eq. 1
In Equation 1, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region extends between a projected area of the face portion (A.sub.f) of 8.3 in.sup.2 to 11.25 in.sup.2 on the x-axis, and extends between about 6.5 in.sup.2 down to the boundary of Equation 1 described above on the y-axis. A narrower novel club head region extends between about 6.0 in.sup.2 and the boundary of Equation 1 on the y-axis, and has an x-axis limit between a projected area of the face portion (A.sub.f) of 8.5 in.sup.2 to 10.75 in.sup.2, 8.75 in.sup.2 to 10.75 in.sup.2, 9.0 in.sup.2 to 10.5 in.sup.2, or 9.0 in.sup.2 to 10.25 in.sup.2.
(100) Turning to
CA=−1.5395*A.sub.f+19.627 Eq. 2
In Equation 2, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region shown in
(101) Turning to
CA=−1.5395*A.sub.f+19.877 Eq. 3
In Equation 3, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region shown in
(102) Turning next to
CA=−1.5395*A.sub.f+17.625 Eq. 4
(103) In Equation 4, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region shown in
(104) Turning next to
CA=−1.5395*A.sub.f+18.725 Eq. 5
In Equation 5, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region shown in
(105) Turning next to
CA=−1.5395*A.sub.f+19.825 Eq. 6
In Equation 6, CA is the 8 mm drop contour area (at the 12 degree pitched orientation), expressed in square inches, and A.sub.f is the projected area of the face portion (as defined hereinabove), also expressed in square inches. The novel club head region shown in
(106) In several embodiments, the larger projected area of the face portion (A.sub.f) may be achieved by providing a golf club head (100) that includes one or more parts formed from a lightweight material, including conventional metallic and nonmetallic materials known and used in the art, such as steel (including stainless steel), titanium alloys, magnesium alloys, aluminum alloys, carbon fiber composite materials, glass fiber composite materials, carbon pre-preg materials, polymeric materials, and the like. For example, in some embodiments, the face (200) may be provided as a face insert formed of a composite material.
(107)
(108)
(109) According to several additional embodiments, a desired combination of a relatively large projected area of the face portion (A.sub.f) and relatively large 8 mm drop contour area (CA) may be obtained by the provision of thin wall construction for one or more parts of the golf club head. Among other advantages, thin wall construction facilitates the redistribution of material from one part of a club head to another part of the club head. Because the redistributed material has a certain mass, the material may be redistributed to locations in the golf club head to enhance performance parameters related to mass distribution, such as CG location and moment of inertia magnitude. Club head material that is capable of being redistributed without affecting the structural integrity of the club head is commonly called discretionary weight. In some embodiments of the presently described high volume aerodynamic golf club head, thin wall construction enables discretionary weight to be removed from one or a combination of the striking plate, crown, skirt, or sole and redistributed in the form of weight ports and corresponding weights.
(110) Thin wall construction can include a thin sole construction, e.g., a sole with a thickness less than about 0.9 mm but greater than about 0.4 mm over at least about 50% of the sole surface area; and/or a thin skirt construction, e.g., a skirt with a thickness less than about 0.8 mm but greater than about 0.4 mm over at least about 50% of the skirt surface area; and/or a thin crown construction, e.g., a crown with a thickness less than about 0.8 mm but greater than about 0.4 mm over at least about 50% of the crown surface area. In one embodiment, the club head is made of titanium and has a thickness less than 0.65 mm over at least 50% of the crown in order to free up enough weight to achieve the desired CG location.
(111) The thin wall construction can be described according to areal weight as defined by the equation below:
AW=ρ.Math.t
In the above equation, AW is defined as areal weight, ρ is defined as density, and t is defined as the thickness of the material. In one exemplary embodiment, the golf club head is made of a material having a density, ρ, of about 4.5 g/cm.sup.3 or less. In one embodiment, the thickness of a crown or sole portion is between about 0.04 cm and about 0.09 cm. Therefore the areal weight of the crown or sole portion is between about 0.18 g/cm.sup.2 and about 0.41 g/cm.sup.2. In some embodiments, the areal weight of the crown or sole portion is less than 0.41 g/cm.sup.2 over at least about 50% of the crown or sole surface area. In other embodiments, the areal weight of the crown or sole is less than about 0.36 g/cm.sup.2 over at least about 50% of the entire crown or sole surface area.
(112) In certain embodiments, the thin wall construction may be implemented according to U.S. patent application Ser. No. 11/870,913 and/or U.S. Pat. No. 7,186,190, which are incorporated by reference herein in their entirety.
(113) Several of the features of the high volume aerodynamic golf club heads described herein—including the provision of a relatively large projected area of the face portion (A.sub.f) and relatively large 8 mm drop contour area (CA)—will tend to cause the location of the center of gravity (CG) to be relatively higher (i.e., larger Ycg value) than a comparably constructed golf club head that does not include these features. Through the provision of one or more of the features described above, such as a lightweight face and/or lightweight construction in other parts of the golf club head, along with relocation of discretionary weight to other parts of the club head, several embodiments of the presently described high volume aerodynamic golf club heads may obtain a desirable downward shift in the location of the center of gravity (CG).
(114) As noted above, the hollow body (110) has center of gravity coordinates (Xcg, Ycg, Zcg) that are described with reference to the origin point, seen in
(115) Several of the high volume aerodynamic golf club embodiments described above in relation to
(116) The high volume aerodynamic golf club head (100) described in relation to
(117) Moreover, several embodiments of the high volume aerodynamic golf club head (100) described in relation to
(118) Still other embodiments of the high volume aerodynamic golf club head (100) described in relation to
(119) Still other embodiments of the club head described in relation to
(120) Several additional embodiments may include a crown apex setback dimension (412) that is less than 1.75 inches. Still other embodiments may include a crown apex (410) location that results in a crown apex ht dimension (414) that is greater than 30% of the HT dimension and less than 70% of the HT dimension, thereby aiding in reducing the period of airflow separation. In an even further embodiment, the crown apex (410) may be located in the heel-to-toe direction between the center of gravity (CG) and the toe (118).
(121) Moreover, the high volume aerodynamic golf club head embodiments described above in relation to
(122) All of the previously described aerodynamic characteristics with respect to the crown section (400) apply equally to the sole section (300) of the high volume aerodynamic golf club head (100). In other words, one skilled in the art will appreciate that just like the crown section (400) has a crown apex (410), the sole section (300) may have a sole apex. Likewise, the three radii of the crown section (400) may just as easily be three radii of the sole section (300). Thus, all of the embodiments described herein with respect to the crown section (400) are incorporated by reference with respect to the sole section (300).
(123) The various parts of the golf club head (100) may be made from any suitable or desired materials without departing from the claimed club head (100), including conventional metallic and nonmetallic materials known and used in the art, such as steel (including stainless steel), titanium alloys, magnesium alloys, aluminum alloys, carbon fiber composite materials, glass fiber composite materials, carbon pre-preg materials, polymeric materials, and the like. The various sections of the club head (100) may be produced in any suitable or desired manner without departing from the claimed club head (100), including in conventional manners known and used in the art, such as by casting, forging, molding (e.g., injection or blow molding), etc. The various sections may be held together as a unitary structure in any suitable or desired manner, including in conventional manners known and used in the art, such as using mechanical connectors, adhesives, cements, welding, brazing, soldering, bonding, and other known material joining techniques. Additionally, the various sections of the golf club head (100) may be constructed from one or more individual pieces, optionally pieces made from different materials having different densities, without departing from the claimed club head (100).
(124) Numerous alterations, modifications, and variations of the preferred embodiments disclosed herein will be apparent to those skilled in the art and they are all anticipated and contemplated to be within the spirit and scope of the instant club head. For example, although specific embodiments have been described in detail, those with skill in the art will understand that the preceding embodiments and variations can be modified to incorporate various types of substitute and or additional or alternative materials, relative arrangement of elements, and dimensional configurations. Accordingly, even though only few variations of the present club head are described herein, it is to be understood that the practice of such additional modifications and variations and the equivalents thereof, are within the spirit and scope of the club head as defined in the following claims. The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or acts for performing the functions in combination with other claimed elements as specifically claimed.