Iron-type golf club head having a sole stress reducing feature

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was not made as part of a federally sponsored research or development project.

TECHNICAL FIELD

The present invention relates to the field of golf clubs, namely hollow golf club heads. The present invention is a hollow golf club head characterized by a stress reducing feature that includes a stress reducing feature having an aperture.

BACKGROUND OF THE INVENTION

The impact associated with a golf club head, often moving in excess of 100 miles per hour, impacting a stationary golf ball results in a tremendous force on the face of the golf club head, and accordingly a significant stress on the face. It is desirable to reduce the peak stress experienced by the face and to selectively distribute the force of impact to other areas of the golf club head where it may be more advantageously utilized.

SUMMARY OF INVENTION

In its most general configuration, the present invention advances the state of the art with a variety of new capabilities and overcomes many of the shortcomings of prior methods in new and novel ways. In its most general sense, the present invention overcomes the shortcomings and limitations of the prior art in any of a number of generally effective configurations.

The present golf club incorporating a stress reducing feature including a crown located SRF, short for stress reducing feature, located on the crown of the club head and/or a sole located SRF located on the sole of the club head. The SRF may contain an aperture extending through the shell of the golf club head. The location and size of the SRF and aperture play a significant role in reducing the peak stress seen on the golf club's face during an impact with a golf ball, as well as selectively increasing deflection of the face.

Numerous variations, modifications, alternatives, and alterations of the various preferred embodiments, processes, and methods may be used alone or in combination with one another as will become more readily apparent to those with skill in the art with reference to the following detailed description of the preferred embodiments and the accompanying figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Without limiting the scope of the present invention as claimed below and referring now to the drawings and figures:

FIG. 1 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 2 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 3 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 4 shows a toe side elevation view of an embodiment of the present invention, not to scale;

FIG. 5 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 6 shows a toe side elevation view of an embodiment of the present invention, not to scale;

FIG. 7 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 8 shows a toe side elevation view of an embodiment of the present invention, not to scale;

FIG. 9 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 10 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 11 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 12 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 13 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 14 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 15 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 16 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 17 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 18 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 19 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 20 shows a toe side elevation view of an embodiment of the present invention, not to scale;

FIG. 21 shows a front elevation view of an embodiment of the present invention, not to scale;

FIG. 22 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 23 shows a bottom plan view of an embodiment of the present invention, not to scale;

FIG. 24 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 25 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 26 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 27 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 28 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 29 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 30 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 31 shows a bottom plan view of an embodiment of the present invention, not to scale;

FIG. 32 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 33 shows a bottom plan view of an embodiment of the present invention, not to scale;

FIG. 34 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 35 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 36 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 37 shows a bottom plan view of an embodiment of the present invention, not to scale;

FIG. 38 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 39 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 40 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 41 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 42 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 43 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 44 shows a graph of face displacement versus load;

FIG. 45 shows a graph of peak stress on the face versus load;

FIG. 46 shows a graph of the stress-to-deflection ratio versus load;

FIG. 47 shows a top plan view of an embodiment of the present invention, not to scale;

FIG. 48 shows a bottom plan view of an embodiment of the present invention, not to scale;

FIG. 49 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 50 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 51 shows a partial cross-sectional view of an embodiment of the present invention, not to scale;

FIG. 52 shows a partial cross-sectional view of an embodiment of the present invention, not to scale; and

FIG. 53 shows a partial cross-sectional view of an embodiment of the present invention, not to scale.

These drawings are provided to assist in the understanding of the exemplary embodiments of the present golf club as described in more detail below and should not be construed as unduly limiting the golf club. 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

The hollow golf club of the present invention enables a significant advance in the state of the art. The preferred embodiments of the golf club accomplish this by new and novel 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 golf club, and is not intended to represent the only form in which the present golf club may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the golf club 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 claimed golf club head.

In order to fully appreciate the present disclosed golf club some common terms must be defined for use herein. First, one of skill in the art will know the meaning of “center of gravity,” referred to herein as CG, from an entry level course on the mechanics of solids. With respect to wood-type golf clubs, hybrid golf clubs, and hollow iron type golf clubs, which are may have non-uniform density, the CG is often thought of as the intersection of all the balance points of the club head. In other words, if you balance the head on the face and then on the sole, the intersection of the two imaginary lines passing straight through the balance points would define the point referred to as the CG.

It is helpful to establish a coordinate system to identify and discuss the location of the CG. In order to establish this coordinate system one must first identify a ground plane (GP) and a shaft axis (SA). First, the ground plane (GP) is the horizontal plane upon which a golf club head rests, as seen best in a front elevation view of a golf club head looking at the face of the golf club head, as seen in FIG. 1. Secondly, the shaft axis (SA) is the axis of a bore in the golf club head that is designed to receive a shaft. Some golf club heads have an external hosel that contains a bore for receiving the shaft such that one skilled in the art can easily appreciate the shaft axis (SA), while other “hosel-less” golf clubs have an internal bore that receives the shaft that nonetheless defines the shaft axis (SA). The shaft axis (SA) is fixed by the design of the golf club head and is also illustrated in FIG. 1.

Now, the intersection of the shaft axis (SA) with the ground plane (GP) fixes an origin point, labeled “origin” in FIG. 1, for the coordinate system. While it is common knowledge in the industry, it is worth noting that the right side of the club head seen in FIG. 1, the side nearest the bore in which the shaft attaches, is the “heel” side of the golf club head; and the opposite side, the left side in FIG. 1, is referred to as the “toe” side of the golf club head. Additionally, the portion of the golf club head that actually strikes a golf ball is referred to as the face of the golf club head and is commonly referred to as the front of the golf club head; whereas the opposite end of the golf club head is referred to as the rear of the golf club head and/or the trailing edge.

A three dimensional coordinate system may now be established from the origin with the Y-direction being the vertical direction from the origin; the X-direction being the horizontal direction perpendicular to the Y-direction and wherein the X-direction is parallel to the face of the golf club head in the natural resting position, also known as the design position; and the Z-direction is perpendicular to the X-direction wherein the Z-direction is the direction toward the rear of the golf club head. The X, Y, and Z directions are noted on a coordinate system symbol in FIG. 1. It should be noted that this coordinate system is contrary to the traditional right-hand rule coordinate system; however it is preferred so that the center of gravity may be referred to as having all positive coordinates.

Now, with the origin and coordinate system defined, the terms that define the location of the CG may be explained. One skilled in the art will appreciate that the CG of a hollow golf club head such as the wood-type golf club head illustrated in FIG. 2 will be behind the face of the golf club head. The distance behind the origin that the CG is located is referred to as Zcg, as seen in FIG. 2. Similarly, the distance above the origin that the CG is located is referred to as Ycg, as seen in FIG. 3. Lastly, the horizontal distance from the origin that the CG is located is referred to as Xcg, also seen in FIG. 3. Therefore, the location of the CG may be easily identified by reference to Xcg, Ycg, and Zcg.

The moment of inertia of the golf club head is a key ingredient in the playability of the club. Again, one skilled in the art will understand what is meant by moment of inertia with respect to golf club heads; however it is helpful to define two moment of inertia components that will be commonly referred to herein. First, MOIx is the moment of inertia of the golf club head around an axis through the CG, parallel to the X-axis, labeled in FIG. 4. MOIx is the moment of inertia of the golf club head that resists lofting and delofting moments induced by ball strikes high or low on the face. Secondly, MOIy is the moment of the inertia of the golf club head around an axis through the CG, parallel to the Y-axis, labeled in FIG. 5. MOIy is the moment of inertia of the golf club head that resists opening and closing moments induced by ball strikes towards the toe side or heel side of the face.

Continuing with the definitions of key golf club head dimensions, the “front-to-back” dimension, referred to as the FB dimension, is the distance from the furthest forward point at the leading edge of the golf club head to the furthest rearward point at the rear of the golf club head, i.e. the trailing edge, as seen in FIG. 6. The “heel-to-toe” dimension, referred to as the HT dimension, is the distance from the point on the surface of the club head on the toe side that is furthest from the origin in the X-direction, to the point on the surface of the golf club head on the heel side that is 0.875″ above the ground plane and furthest from the origin in the negative X-direction, as seen in FIG. 7.

A key location on the golf club face is an engineered impact point (EIP). The engineered impact point (EIP) is important in that it helps define several other key attributes of the present golf club head. The engineered impact point (EIP) is generally thought of as the point on the face that is the ideal point at which to strike the golf ball. Generally, the score lines on golf club heads enable one to easily identify the engineered impact point (EIP) for a golf club. In the embodiment of FIG. 9, the first step in identifying the engineered impact point (EIP) is to identify the top score line (TSL) and the bottom score line (BSL). Next, draw an imaginary line (IL) from the midpoint of the top score line (TSL) to the midpoint of the bottom score line (BSL). This imaginary line (IL) will often not be vertical since many score line designs are angled upward toward the toe when the club is in the natural position. Next, as seen in FIG. 10, the club must be rotated so that the top score line (TSL) and the bottom score line (BSL) are parallel with the ground plane (GP), which also means that the imaginary line (IL) will now be vertical. In this position, the leading edge height (LEH) and the top edge height (TEH) are measured from the ground plane (GP). Next, the face height is determined by subtracting the leading edge height (LEH) from the top edge height (TEH). The face height is then divided in half and added to the leading edge height (LEH) to yield the height of the engineered impact point (EIP). Continuing with the club head in the position of FIG. 10, a spot is marked on the imaginary line (IL) at the height above the ground plane (GP) that was just calculated. This spot is the engineered impact point (EIP).

The engineered impact point (EIP) may also be easily determined for club heads having alternative score line configurations. For instance, the golf club head of FIG. 11 does not have a centered top score line. In such a situation, the two outermost score lines that have lengths within 5% of one another are then used as the top score line (TSL) and the bottom score line (BSL). The process for determining the location of the engineered impact point (EIP) on the face is then determined as outlined above. Further, some golf club heads have non-continuous score lines, such as that seen at the top of the club head face in FIG. 12. In this case, a line is extended across the break between the two top score line sections to create a continuous top score line (TSL). The newly created continuous top score line (TSL) is then bisected and used to locate the imaginary line (IL). Again, then the process for determining the location of the engineered impact point (EIP) on the face is determined as outlined above.

The engineered impact point (EIP) may also be easily determined in the rare case of a golf club head having an asymmetric score line pattern, or no score lines at all. In such embodiments the engineered impact point (EIP) 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. In these limited cases of asymmetric score line patterns, or no score lines at all, this USGA face center shall be the engineered impact point (EIP) that is referenced throughout this application.

The engineered impact point (EIP) on the face is an important reference to define other attributes of the present golf club head. The engineered impact point (EIP) is generally shown on the face with rotated crosshairs labeled EIP. The precise location of the engineered impact point (EIP) can be identified via the dimensions Xeip, Yeip, and Zeip, as illustrated in FIGS. 22-24. The X coordinate Xeip is measured in the same manner as Xcg, the Y coordinate Yeip is measured in the same manner as Ycg, and the Z coordinate Zeip is measured in the same manner as Zcg, except that Zeip is always a positive value regardless of whether it is in front of the origin point or behind the origin point.

One important dimension that utilizes the engineered impact point (EIP) is the center face progression (CFP), seen in FIGS. 8 and 14. The center face progression (CFP) is a single dimension measurement and is defined as the distance in the Z-direction from the shaft axis (SA) to the engineered impact point (EIP). A second dimension that utilizes the engineered impact point (EIP) is referred to as a club moment arm (CMA). The CMA is the two dimensional distance from the CG of the club head to the engineered impact point (EIP) on the face, as seen in FIG. 8. Thus, with reference to the coordinate system shown in FIG. 1, the club moment arm (CMA) includes a component in the Z-direction and a component in the Y-direction, but ignores any difference in the X-direction between the CG and the engineered impact point (EIP). Thus, the club moment arm (CMA) can be thought of in terms of an impact vertical plane passing through the engineered impact point (EIP) and extending in the Z-direction. First, one would translate the CG horizontally in the X-direction until it hits the impact vertical plane. Then, the club moment arm (CMA) would be the distance from the projection of the CG on the impact vertical plane to the engineered impact point (EIP). The club moment arm (CMA) has a significant impact on the launch angle and the spin of the golf ball upon impact.

Another important dimension in golf club design is the club head blade length (BL), seen in FIG. 13 and FIG. 14. The blade length (BL) is the distance from the origin to a point on the surface of the club head on the toe side that is furthest from the origin in the X-direction. The blade length (BL) is composed of two sections, namely the heel blade length section (Abl) and the toe blade length section (Bbl). The point of delineation between these two sections is the engineered impact point (EIP), or more appropriately, a vertical line, referred to as a face centerline (FC), extending through the engineered impact point (EIP), as seen in FIG. 13, when the golf club head is in the normal resting position, also referred to as the design position.

Further, several additional dimensions are helpful in understanding the location of the CG with respect to other points that are essential in golf club engineering. First, a CG angle (CGA) is the one dimensional angle between a line connecting the CG to the origin and an extension of the shaft axis (SA), as seen in FIG. 14. The CG angle (CGA) is measured solely in the X-Z plane and therefore does not account for the elevation change between the CG and the origin, which is why it is easiest understood in reference to the top plan view of FIG. 14.

Lastly, another important dimension in quantifying the present golf club only takes into consideration two dimensions and is referred to as the transfer distance (TD), seen in FIG. 17. The transfer distance (TD) is the horizontal distance from the CG to a vertical line extending from the origin; thus, the transfer distance (TD) ignores the height of the CG, or Ycg. Thus, using the Pythagorean Theorem from simple geometry, the transfer distance (TD) is the hypotenuse of a right triangle with a first leg being Xcg and the second leg being Zcg.

The transfer distance (TD) is significant in that is helps define another moment of inertia value that is significant to the present golf club. This new moment of inertia value is defined as the face closing moment of inertia, referred to as MOIfc, which is the horizontally translated (no change in Y-direction elevation) version of MOIy around a vertical axis that passes through the origin. MOIfc is calculated by adding MOIy to the product of the club head mass and the transfer distance (TD) squared. Thus,

MOIfc=MOIy+(mass*(TD)²)

The face closing moment (MOIfc) is important because is represents the resistance that a golfer feels during a swing when trying to bring the club face back to a square position for impact with the golf ball. In other words, as the golf swing returns the golf club head to its original position to impact the golf ball the face begins closing with the goal of being square at impact with the golf ball.

The presently disclosed hollow golf club incorporates stress reducing features unlike prior hollow type golf clubs. The hollow type golf club includes a shaft (200) having a proximal end (210) and a distal end (220); a grip (300) attached to the shaft proximal end (210); and a golf club head (100) attached at the shaft distal end (220), as seen in FIG. 21. The overall hollow type golf club has a club length of at least 36 inches and no more than 45 inches, as measure in accordance with USGA guidelines.

The golf club head (400) itself is a hollow structure that includes a face (500) positioned at a front portion (402) of the golf club head (400) where the golf club head (400) impacts a golf ball, a sole (700) positioned at a bottom portion of the golf club head (400), a crown (600) positioned at a top portion of the golf club head (400), and a skirt (800) positioned around a portion of a periphery of the golf club head (400) between the sole (700) and the crown (800). The face (500), sole (700), crown (600), and skirt (800) define an outer shell that further defines a head volume that is less than 300 cubic centimeters for the golf club head (400). Additionally, the golf club head (400) has a rear portion (404) opposite the face (500). The rear portion (404) includes the trailing edge of the golf club head (400), as is understood by one with skill in the art. The face (500) has a loft (L) of at least 12 degrees and no more than 30 degrees, and the face (500) includes an engineered impact point (EIP) as defined above. One skilled in the art will appreciate that the skirt (800) may be significant at some areas of the golf club head (400) and virtually nonexistent at other areas; particularly at the rear portion (404) of the golf club head (400) where it is not uncommon for it to appear that the crown (600) simply wraps around and becomes the sole (700).

The golf club head (100) includes a bore having a center that defines a shaft axis (SA) that intersects with a horizontal ground plane (GP) to define an origin point, as previously explained. The bore is located at a heel side (406) of the golf club head (400) and receives the shaft distal end (220) for attachment to the golf club head (400). The golf club head (100) also has a toe side (408) located opposite of the heel side (406). The presently disclosed golf club head (400) has a club head mass of less than 270 grams, which combined with the previously disclosed loft, club head volume, and club length establish that the presently disclosed golf club is directed to a hollow golf club such as a fairway wood, hybrid, or hollow iron.

The golf club head (400) may include a stress reducing feature (1000) including a crown located SRF (1100) located on the crown (600), seen in FIG. 22, and/or a sole located SRF (1300) located on the sole (700), seen in FIG. 23. As seen in FIGS. 22 and 25, the crown located SRF (1100) has a CSRF length (1110) between a CSRF toe-most point (1112) and a CSRF heel-most point (1116), a CSRF leading edge (1120), a CSRF trailing edge (1130), a CSRF width (1140), and a CSRF depth (1150). Similarly, as seen in FIGS. 23 and 25, the sole located SRF (1300) has a SSRF length (1310) between a SSRF toe-most point (1312) and a SSRF heel-most point (1316), a SSRF leading edge (1320), a SSRF trailing edge (1330), a SSRF width (1340), and a SSRF depth (1350).

With reference now to FIG. 24, in embodiments which incorporate both a crown located SRF (1100) and a sole located SRF (1300), a SRF connection plane (1500) passes through a portion of the crown located SRF (1100) and the sole located SRF (1300). To locate the SRF connection plane (1500) a vertical section is taken through the club head (400) in a front-to-rear direction, perpendicular to a vertical plane created by the shaft axis (SA); such a section is seen in FIG. 24. Then a crown SRF midpoint of the crown located SRF (1100) is determined at a location on a crown imaginary line following the natural curvature of the crown (600). The crown imaginary line is illustrated in FIG. 24 with a broken, or hidden, line connecting the CSRF leading edge (1120) to the CSRF trailing edge (1130), and the crown SRF midpoint is illustrated with an X. Similarly, a sole SRF midpoint of the sole located SRF (1300) is determined at a location on a sole imaginary line following the natural curvature of the sole (700). The sole imaginary line is illustrated in FIG. 24 with a broken, or hidden, line connecting the SSRF leading edge (1320) to the SSRF trailing edge (1330), and the sole SRF midpoint is illustrated with an X. Finally, the SRF connection plane (1500) is a plane in the heel-to-toe direction that passes through both the crown SRF midpoint and the sole SRF midpoint, as seen in FIG. 24. While the SRF connection plane (1500) illustrated in FIG. 24 is approximately vertical, the orientation of the SRF connection plane (1500) depends on the locations of the crown located SRF (1100) and the sole located SRF (1300) and may be angled toward the face, as seen in FIG. 26, or angled away from the face, as seen in FIG. 27.

The SRF connection plane (1500) is oriented at a connection plane angle (1510) from the vertical, seen in FIGS. 26 and 27, which aids in defining the location of the crown located SRF (1100) and the sole located SRF (1300). In one particular embodiment the crown located SRF (1100) and the sole located SRF (1300) are not located vertically directly above and below one another; rather, the connection plane angle (1510) is greater than zero and less than ninety percent of a loft (L) of the club head (400), as seen in FIG. 26. The sole located SRF (1300) could likewise be located in front of, i.e. toward the face (500), the crown located SRF (1100) and still satisfy the criteria of this embodiment; namely, that the connection plane angle (1510) is greater than zero and less than ninety percent of a loft of the club head (400).

In an alternative embodiment, seen in FIG. 27, the SRF connection plane (1500) is oriented at a connection plane angle (1510) from the vertical and the connection plane angle (1510) is at least ten percent greater than a loft (L) of the club head (400). The crown located SRF (1100) could likewise be located in front of, i.e. toward the face (500), the sole located SRF (1300) and still satisfy the criteria of this embodiment; namely, that the connection plane angle (1510) is at least ten percent greater than a loft (L) of the club head (400). In an even further embodiment the SRF connection plane (1500) is oriented at a connection plane angle (1510) from the vertical and the connection plane angle (1510) is at least fifty percent greater than a loft (L) of the club head (400), but less than one hundred percent greater than the loft (L). These three embodiments recognize a unique relationship between the crown located SRF (1100) and the sole located SRF (1300) such that they are not vertically aligned with one another, while also not merely offset in a manner matching the loft (L) of the club head (400).

With reference now to FIGS. 30 and 31, in the event that a crown located SRF (1100) or a sole located SRF (1300), or both, do not exist at the location of the CG section, labeled as section 24-24 in FIG. 22, then the crown located SRF (1100) located closest to the front-to-rear vertical plane passing through the CG is selected. For example, as seen in FIG. 30 the right crown located SRF (1100) is nearer to the front-to-rear vertical CG plane than the left crown located SRF (1100). In other words the illustrated distance “A” is smaller for the right crown located SRF (1100). Next, the face centerline (FC) is translated until it passes through both the CSRF leading edge (1120) and the CSRF trailing edge (1130), as illustrated by broken line “B”. Then, the midpoint of line “B” is found and labeled “C”. Finally, imaginary line “D” is created that is perpendicular to the “B” line.

The same process is repeated for the sole located SRF (1300), as seen in FIG. 31. It is simply a coincidence that both the crown located SRF (1100) and the sole located SRF (1300) located closest to the front-to-rear vertical CG plane are both on the heel side (406) of the golf club head (400). The same process applies even when the crown located SRF (1100) and the sole located SRF (1300) located closest to the front-to-rear vertical CG plane are on opposites sides of the golf club head (400). Now, still referring to FIG. 31, the process first involves identifying that the right sole located SRF (1300) is nearer to the front-to-rear vertical CG plane than the left sole located SRF (1300). In other words the illustrated distance “E” is smaller for the heel-side sole located SRF (1300). Next, the face centerline (FC) is translated until it passes through both the SSRF leading edge (1320) and the SSRF trailing edge (1330), as illustrated by broken line “F”. Then, the midpoint of line “F” is found and labeled “G”. Finally, imaginary line “H” is created that is perpendicular to the “F” line. The plane passing through both the imaginary line “D” and imaginary line “H” is the SRF connection plane (1500).

Next, referring back to FIG. 24, a CG-to-plane offset (1600) is defined as the shortest distance from the center of gravity (CG) to the SRF connection plane (1500), regardless of the location of the CG. In one particular embodiment the CG-to-plane offset (1600) is at least twenty-five percent less than the club moment arm (CMA) and the club moment arm (CMA) is less than 1.3 inches. The locations of the crown located SRF (1100) and the sole located SRF (1300) described herein, and the associated variables identifying the location, are selected to preferably reduce the stress in the face (500) when impacting a golf ball while accommodating temporary flexing and deformation of the crown located SRF (1100) and sole located SRF (1300) in a stable manner in relation to the CG location, and/or origin point, while maintaining the durability of the face (500), the crown (600), and the sole (700). Experimentation and modeling has shown that the crown located SRF (1100) and the sole located SRF (1300) increase the deflection of the face (500), while also reduce the peak stress on the face (500) at impact with a golf ball. This reduction in stress allows a substantially thinner face to be utilized, permitting the weight savings to be distributed elsewhere in the club head (400). Further, the increased deflection of the face (500) facilitates improvements in the coefficient of restitution (COR) of the club head (400), particularly for club heads having a volume of 300 cc or less.

In fact, further embodiments even more precisely identify the location of the crown located SRF (1100) and/or the sole located SRF (1300) to achieve these objectives. For instance, in one further embodiment the CG-to-plane offset (1600) is at least twenty-five percent of the club moment arm (CMA) and less than seventy-five percent of the club moment arm (CMA). In still a further embodiment, the CG-to-plane offset (1600) is at least forty percent of the club moment arm (CMA) and less than sixty percent of the club moment arm (CMA).

Alternatively, another embodiment relates the location of the crown located SRF (1100) and/or the sole located SRF (1300) to the difference between the maximum top edge height (TEH) and the minimum lower edge (LEH), referred to as the face height, rather than utilizing the CG-to-plane offset (1600) variable as previously discussed to accommodate embodiments in which a single SRF is present. As such, two additional variables are illustrated in FIG. 24, namely the CSRF leading edge offset (1122) and the SSRF leading edge offset (1322). The CSRF leading edge offset (1122) is the distance from any point along the CSRF leading edge (1120) directly forward, in the Zcg direction, to the point at the top edge (510) of the face (500). Thus, the CSRF leading edge offset (1122) may vary along the length of the CSRF leading edge (1120), or it may be constant if the curvature of the CSRF leading edge (1120) matches the curvature of the top edge (510) of the face (500). Nonetheless, there will always be a minimum CSRF leading edge offset (1122) at the point along the CSRF leading edge (1120) that is the closest to the corresponding point directly in front of it on the face top edge (510), and there will be a maximum CSRF leading edge offset (1122) at the point along the CSRF leading edge (1120) that is the farthest from the corresponding point directly in front of it on the face top edge (510). Likewise, the SSRF leading edge offset (1322) is the distance from any point along the SSRF leading edge (1320) directly forward, in the Zcg direction, to the point at the lower edge (520) of the face (500). Thus, the SSRF leading edge offset (1322) may vary along the length of the SSRF leading edge (1320), or it may be constant if the curvature of SSRF leading edge (1320) matches the curvature of the lower edge (520) of the face (500). Nonetheless, there will always be a minimum SSRF leading edge offset (1322) at the point along the SSRF leading edge (1320) that is the closest to the corresponding point directly in front of it on the face lower edge (520), and there will be a maximum SSRF leading edge offset (1322) at the point along the SSRF leading edge (1320) that is the farthest from the corresponding point directly in front of it on the face lower edge (520). Generally, the maximum CSRF leading edge offset (1122) and the maximum SSRF leading edge offset (1322) will be less than seventy-five percent of the face height. For the purposes of this application and ease of definition, the face top edge (510) is the series of points along the top of the face (500) at which the vertical face roll becomes less than one inch, and similarly the face lower edge (520) is the series of points along the bottom of the face (500) at which the vertical face roll becomes less than one inch.

In this particular embodiment, the minimum CSRF leading edge offset (1122) is less than the face height, while the minimum SSRF leading edge offset (1322) is at least two percent of the face height. In an even further embodiment, the maximum CSRF leading edge offset (1122) is also less than the face height. Yet another embodiment incorporates a minimum CSRF leading edge offset (1122) that is at least ten percent of the face height, and the minimum CSRF width (1140) is at least fifty percent of the minimum CSRF leading edge offset (1122). A still further embodiment more narrowly defines the minimum CSRF leading edge offset (1122) as being at least twenty percent of the face height.

Likewise, many embodiments are directed to advantageous relationships of the sole located SRF (1300). For instance, in one embodiment, the minimum SSRF leading edge offset (1322) is at least ten percent of the face height, and the minimum SSRF width (1340) is at least fifty percent of the minimum SSRF leading edge offset (1322). Even further, another embodiment more narrowly defines the minimum SSRF leading edge offset (1322) as being at least twenty percent of the face height.

Still further building upon the relationships among the CSRF leading edge offset (1122), the SSRF leading edge offset (1322), and the face height, one embodiment further includes an engineered impact point (EIP) having a Yeip coordinate such that the difference between Yeip and Ycg is less than 0.5 inches and greater than −0.5 inches; a Xeip coordinate such that the difference between Xeip and Xcg is less than 0.5 inches and greater than −0.5 inches; and a Zeip coordinate such that the total of Zeip and Zcg is less than 2.0 inches. These relationships among the location of the engineered impact point (EIP) and the location of the center of gravity (CG) in combination with the leading edge locations of the crown located SRF (1100) and/or the sole located SRF (1300) promote stability at impact, while accommodating desirable deflection of the SRFs (1100, 1300) and the face (500), while also maintaining the durability of the club head (400) and reducing the peak stress experienced in the face (500).

While the location of the crown located SRF (1100) and/or the sole located SRF (1300) is important in achieving these objectives, the size of the crown located SRF (1100) and the sole located SRF (1300) also plays a role. In one particular long blade length embodiment directed to fairway wood type golf clubs and hybrid type golf clubs, illustrated in FIGS. 42 and 43, the golf club head (400) has a blade length (BL) of at least 3.0 inches with a heel blade length section (Abl) of at least 0.8 inches. In this embodiment, preferable results are obtained when the CSRF length (1110) is at least as great as the heel blade length section (Abl) and the maximum CSRF depth (1150) is at least ten percent of the Ycg distance, thereby permitting adequate compression and/or flexing of the crown located SRF (1100) to significantly reduce the stress on the face (500) at impact. Similarly, in some SSRF embodiments, preferable results are obtained when the SSRF length (1310) is at least as great as the heel blade length section (Abl) and the maximum SSRF depth (1350) is at least ten percent of the Ycg distance, thereby permitting adequate compression and/or flexing of the sole located SRF (1300) to significantly reduce the stress on the face (500) at impact. It should be noted at this point that the cross-sectional profile of the crown located SRF (1100) and the sole mounted SRF (1300) may include any number of shapes including, but not limited to, a box-shape, as seen in FIG. 24, a smooth U-shape, as seen in FIG. 28, and a V-shape, as seen in FIG. 29. Further, the crown located SRF (1100) and the sole located SRF (1300) may include reinforcement areas as seen in FIGS. 40 and 41 to further selectively control the deformation of the SRFs (1100, 1300). Additionally, the CSRF length (1110) and the SSRF length (1310) are measured in the same direction as Xcg rather than along the curvature of the SRFs (1100, 1300), if curved.

The crown located SRF (1100) has a CSRF wall thickness (1160) and sole located SRF (1300) has a SSRF wall thickness (1360), as seen in FIG. 25. In most embodiments the CSRF wall thickness (1160) and the SSRF wall thickness (1360) will be at least 0.010 inches and no more than 0.150 inches. In particular embodiment has found that having the CSRF wall thickness (1160) and the SSRF wall thickness (1360) in the range often percent to sixty percent of the face thickness (530) achieves the required durability while still providing desired stress reduction in the face (500) and deflection of the face (500). Further, this range facilitates the objectives while not have a dilutive effect, nor overly increasing the weight distribution of the club head (400) in the vicinity of the SRFs (1100, 1300).

Further, the terms maximum CSRF depth (1150) and maximum SSRF depth (1350) are used because the depth of the crown located SRF (1100) and the depth of the sole located SRF (1300) need not be constant; in fact, they are likely to vary, as seen in FIGS. 32-35. Additionally, the end walls of the crown located SRF (1100) and the sole located SRF (1300) need not be distinct, as seen on the right and left side of the SRFs (1100, 1300) seen in FIG. 35, but may transition from the maximum depth back to the natural contour of the crown (600) or sole (700). The transition need not be smooth, but rather may be stepwise, compound, or any other geometry. In fact, the presence or absence of end walls is not necessary in determining the bounds of the claimed golf club. Nonetheless, a criteria needs to be established for identifying the location of the CSRF toe-most point (1112), the CSRF heel-most point (1116), the SSRF toe-most point (1312), and the SSRF heel-most point (1316); thus, when not identifiable via distinct end walls, these points occur where a deviation from the natural curvature of the crown (600) or sole (700) is at least ten percent of the maximum CSRF depth (1150) or maximum SSRF depth (1350). In most embodiments a maximum CSRF depth (1150) and a maximum SSRF depth (1350) of at least 0.100 inches and no more than 0.500 inches is preferred.

The CSRF leading edge (1120) may be straight or may include a CSRF leading edge radius of curvature (1124), as seen in FIG. 36. Likewise, the SSRF leading edge (1320) may be straight or may include a SSRF leading edge radius of curvature (1324), as seen in FIG. 37. One particular embodiment incorporates both a curved CSRF leading edge (1120) and a curved SSRF leading edge (1320) wherein both the CSRF leading edge radius of curvature (1124) and the SSRF leading edge radius of curvature (1324) are within forty percent of the curvature of the bulge of the face (500). In an even further embodiment both the CSRF leading edge radius of curvature (1124) and the SSRF leading edge radius of curvature (1324) are within twenty percent of the curvature of the bulge of the face (500). These curvatures further aid in the controlled deflection of the face (500).

One particular embodiment, illustrated in FIGS. 32-35, has a CSRF depth (1150) that is less at the face centerline (FC) than at a point on the toe side (408) of the face centerline (FC) and at a point on the heel side (406) of the face centerline (FC), thereby increasing the potential deflection of the face (500) at the heel side (406) and the toe side (408), where the COR is generally lower than the USGA permitted limit. In another embodiment, the crown located SRF (1100) and/or the sole located SRF (1300) have reduced depth regions, namely a CSRF reduced depth region (1152) and a SSRF reduced depth region (1352), as seen in FIG. 35. Each reduced depth region is characterized as a continuous region having a depth that is at least twenty percent less than the maximum depth for the particular SRF (1100, 1300). The CSRF reduced depth region (1152) has a CSRF reduced depth length (1154) and the SSRF reduced depth region (1352) has a SSRF reduced depth length (1354). In one particular embodiment, each reduced depth length (1154, 1354) is at least fifty percent of the heel blade length section (Abl). A further embodiment has the CSRF reduced depth region (1152) and the SSRF reduced depth region (1352) approximately centered about the face centerline (FC), as seen in FIG. 35. Yet another embodiment incorporates a design wherein the CSRF reduced depth length (1154) is at least thirty percent of the CSRF length (1110), and/or the SSRF reduced depth length (1354) is at least thirty percent of the SSRF length (1310). In addition to aiding in achieving the objectives set out above, the reduced depth regions (1152, 1352) may improve the life of the SRFs (1100, 1300) and reduce the likelihood of premature failure, while increasing the COR at desirable locations on the face (500).

As seen in FIG. 25, the crown located SRF (1100) has a CSRF cross-sectional area (1170) and the sole located SRF (1300) has a SSRF cross-sectional area (1370). The cross-sectional areas are measured in cross-sections that run from the front portion (402) to the rear portion (404) of the club head (400) in a vertical plane. Just as the cross-sectional profiles (1190, 1390) of FIGS. 28 and 29 may change throughout the CSRF length (1110) and the SSRF length (1310), the CSRF cross-sectional area (1170) and/or the SSRF cross-sectional area (1370) may also vary along the lengths (1110, 1310). In fact, in one particular embodiment, the CSRF cross-sectional area (1170) is less at the face centerline (FC) than at a point on the toe side (408) of the face centerline (FC) and a point on the heel side (406) of the face centerline (FC). Similarly, in another embodiment, the SSRF cross-sectional area (1370) is less at the face centerline than at a point on the toe side (408) of the face centerline (FC) and a point on the heel side (406) of the face centerline (FC); and yet a third embodiment incorporates both of the prior two embodiments related to the CSRF cross-sectional area (1170) and the SSRF cross-sectional area (1370). In one particular embodiment, the CSRF cross-sectional area (1170) and/or the SSRF cross-sectional area (1370) fall within the range of 0.005 square inches to 0.375 square inches. Additionally, the crown located SRF (1100) has a CSRF volume and the sole located SRF (1300) has a SSRF volume. In one embodiment the combined CSRF volume and SSRF volume is at least 0.5 percent of the club head volume and less than 10 percent of the club head volume, as this range facilitates the objectives while not have a dilutive effect, nor overly increasing the weight distribution of the club head (400) in the vicinity of the SRFs (1100, 1300). In yet another embodiment directed to single SRF variations, the individual volume of the CSRF volume or the SSRF volume is preferably at least 1 percent of the club head volume and less than 5 percent of the club head volume to facilitate the objectives while not have a dilutive effect, nor overly increasing the weight distribution of the club head (400) in the vicinity of the SRFs (1100, 1300). The volumes discussed above are not meant to limit the SRFs (1100, 1300) to being hollow channels, for instance the volumes discussed will still exist even if the SRFs (1100, 1300) are subsequently filled with a secondary material, as seen in FIG. 51, or covered, such that the volume is not visible to a golfer. The secondary material should be elastic, have a compressive strength less than half of the compressive strength of the outer shell, and a density less than 3 g/cm³.

Now, in another separate embodiment seen in FIGS. 36 and 37, a CSRF origin offset (1118) is defined as the distance from the origin point to the CSRF heel-most point (1116) in the same direction as the Xcg distance such that the CSRF origin offset (1118) is a positive value when the CSRF heel-most point (1116) is located toward the toe side (408) of the golf club head (400) from the origin point, and the CSRF origin offset (1118) is a negative value when the CSRF heel-most point (1116) is located toward the heel side (406) of the golf club head (400) from the origin point. Similarly, in this embodiment, a SSRF origin offset (1318) is defined as the distance from the origin point to the SSRF heel-most point (1316) in the same direction as the Xcg distance such that the SSRF origin offset (1318) is a positive value when the SSRF heel-most point (1316) is located toward the toe side (408) of the golf club head (400) from the origin point, and the SSRF origin offset (1318) is a negative value when the SSRF heel-most point (1316) is located toward the heel side (406) of the golf club head (400) from the origin point.

In one particular embodiment, seen in FIG. 37, the SSRF origin offset (1318) is a positive value, meaning that the SSRF heel-most point (1316) stops short of the origin point. Further, yet another separate embodiment is created by combining the embodiment illustrated in FIG. 36 wherein the CSRF origin offset (1118) is a negative value, in other words the CSRF heel-most point (1116) extends past the origin point, and the magnitude of the CSRF origin offset (1118) is at least five percent of the heel blade length section (Abl). However, an alternative embodiment incorporates a CSRF heel-most point (1116) that does not extend past the origin point and therefore the CSRF origin offset (1118) is a positive value with a magnitude of at least five percent of the heel blade length section (Abl). In these particular embodiments, locating the CSRF heel-most point (1116) and the SSRF heel-most point (1316) such that they are no closer to the origin point than five percent of the heel blade length section (Abl) is desirable in achieving many of the objectives discussed herein over a wide range of ball impact locations.

Still further embodiments incorporate specific ranges of locations of the CSRF toe-most point (1112) and the SSRF toe-most point (1312) by defining a CSRF toe offset (1114) and a SSRF toe offset (1314), as seen in FIGS. 36 and 37. The CSRF toe offset (1114) is the distance measured in the same direction as the Xcg distance from the CSRF toe-most point (1112) to the most distant point on the toe side (408) of golf club head (400) in this direction, and likewise the SSRF toe offset (1314) is the distance measured in the same direction as the Xcg distance from the SSRF toe-most point (1312) to the most distant point on the toe side (408) of golf club head (400) in this direction. One particular embodiment found to produce preferred face stress distribution and compression and flexing of the crown located SRF (1100) and the sole located SRF (1300) incorporates a CSRF toe offset (1114) that is at least fifty percent of the heel blade length section (Abl) and a SSRF toe offset (1314) that is at least fifty percent of the heel blade length section (Abl). In yet a further embodiment the CSRF toe offset (1114) and the SSRF toe offset (1314) are each at least fifty percent of a golf ball diameter; thus, the CSRF toe offset (1114) and the SSRF toe offset (1314) are each at 0.84 inches. These embodiments also minimally affect the integrity of the club head (400) as a whole, thereby ensuring the desired durability, particularly at the heel side (406) and the toe side (408) while still allowing for improved face deflection during off center impacts.

Even more embodiments now turn the focus to the size of the crown located SRF (1100) and the sole located SRF (1300). One such embodiment has a maximum CSRF width (1140) that is at least ten percent of the Zcg distance, and the maximum SSRF width (1340) is at least ten percent of the Zcg distance, further contributing to increased stability of the club head (400) at impact. Still further embodiments increase the maximum CSRF width (1140) and the maximum SSRF width (1340) such that they are each at least forty percent of the Zcg distance, thereby promoting deflection and selectively controlling the peak stresses seen on the face (500) at impact. An alternative embodiment relates the maximum CSRF depth (1150) and the maximum SSRF depth (1350) to the face height rather than the Zcg distance as discussed above. For instance, yet another embodiment incorporates a maximum CSRF depth (1150) that is at least five percent of the face height, and a maximum SSRF depth (1350) that is at least five percent of the face height. An even further embodiment incorporates a maximum CSRF depth (1150) that is at least twenty percent of the face height, and a maximum SSRF depth (1350) that is at least twenty percent of the face height, again, promoting deflection and selectively controlling the peak stresses seen on the face (500) at impact. In most embodiments a maximum CSRF width (1140) and a maximum SSRF width (1340) of at least 0.050 inches and no more than 0.750 inches is preferred.

Additional embodiments focus on the location of the crown located SRF (1100) and the sole located SRF (1300) with respect to a vertical plane defined by the shaft axis (SA) and the Xcg direction. One such embodiment has recognized improved stability and lower peak face stress when the crown located SRF (1100) and/or the sole located SRF (1300) are located behind the shaft axis plane. Further embodiments additionally define this relationship. In one such embodiment, the CSRF leading edge (1120) is located behind the shaft axis plane a distance that is at least twenty percent of the Zcg distance. Yet anther embodiment focuses on the location of the sole located SRF (1300) such that the SSRF leading edge (1320) is located behind the shaft axis plane a distance that is at least ten percent of the Zcg distance. An even further embodiment focusing on the crown located SRF (1100) incorporates a CSRF leading edge (1120) that is located behind the shaft axis plane a distance that is at least seventy-five percent of the Zcg distance. A similar embodiment directed to the sole located SRF (1300) has a SSRF leading edge (1320) that is located behind the shaft axis plane a distance that is at least seventy-five percent of the Zcg distance. Similarly, the locations of the CSRF leading edge (1120) and SSRF leading edge (1320) behind the shaft axis plane may also be related to the face height instead of the Zcg distance discussed above. For instance, in one embodiment, the CSRF leading edge (1120) is located a distance behind the shaft axis plane that is at least ten percent of the face height. A further embodiment focuses on the location of the sole located SRF (1300) such that the SSRF leading edge (1320) is located behind the shaft axis plane a distance that is at least five percent of the Zcg distance. An even further embodiment focusing on both the crown located SRF (1100) and the sole located SRF (1300) incorporates a CSRF leading edge (1120) that is located behind the shaft axis plane a distance that is at least fifty percent of the face height, and a SSRF leading edge (1320) that is located behind the shaft axis plane a distance that is at least fifty percent of the face height.

The club head (400) is not limited to a single crown located SRF (1100) and/or a single sole located SRF (1300). In fact, many embodiments incorporating multiple crown located SRFs (1100) and/or multiple sole located SRFs (1300) are illustrated in FIGS. 30, 31, and 39, showing that the multiple SRFs (1100, 1300) may be positioned beside one another in a heel-toe relationship, or may be positioned behind one another in a front-rear orientation. As such, one particular embodiment includes at least two crown located SRFs (1100) positioned on opposite sides of the engineered impact point (EIP) when viewed in a top plan view, as seen in FIG. 31, thereby further selectively increasing the COR and improving the peak stress on the face (500). Traditionally, the COR of the face (500) gets smaller as the measurement point is moved further away from the engineered impact point (EIP); and thus golfers that hit the ball toward the heel side (406) or toe side (408) of the a golf club head do not benefit from a high COR. As such, positioning of the two crown located SRFs (1100) seen in FIG. 30 facilitates additional face deflection for shots struck toward the heel side (406) or toe side (408) of the golf club head (400). Another embodiment, as seen in FIG. 31, incorporates the same principles just discussed into multiple sole located SRFs (1300).

The impact of a club head (400) and a golf ball may be simulated in many ways, both experimentally and via computer modeling. First, an experimental process will be explained because it is easy to apply to any golf club head and is free of subjective considerations. The process involves applying a force to the face (500) distributed over a 0.6 inch diameter centered about the engineered impact point (EIP). A force of 4000 lbf is representative of an approximately 100 mph impact between a club head (400) and a golf ball, and more importantly it is an easy force to apply to the face and reliably reproduce. The club head boundary condition consists of fixing the rear portion (404) of the club head (400) during application of the force. In other words, a club head (400) can easily be secured to a fixture within a material testing machine and the force applied. Generally, the rear portion (404) experiences almost no load during an actual impact with a golf ball, particularly as the “front-to-back” dimension (FB) increases. The peak deflection of the face (500) under the force is easily measured and is very close to the peak deflection seen during an actual impact, and the peak deflection has a linear correlation to the COR. A strain gauge applied to the face (500) can measure the actual stress. This experimental process takes only minutes to perform and a variety of forces may be applied to any club head (400); further, computer modeling of a distinct load applied over a certain area of a club face (500) is much quicker to simulate than an actual dynamic impact.

A graph of displacement versus load is illustrated in FIG. 44 for a club head having no stress reducing feature (1000), a club head (400) having only a sole located SRF (1300), and a club head (400) having both a crown located SRF (1100) and a sole located SRF (1300), at the following loads of 1000 lbf, 2000 lbf, 3000 lbf, and 4000 lbf, all of which are distributed over a 0.6 inch diameter area centered on the engineered impact point (EIP). The face thickness (530) was held a constant 0.090 inches for each of the three club heads. Incorporation of a crown located SRF (1100) and a sole located SRF (1300) as described herein increases face deflection by over 11% at the 4000 lbf load level, from a value of 0.027 inches to 0.030 inches. In one particular embodiment, the increased deflection resulted in an increase in the characteristic time (CT) of the club head from 187 microseconds to 248 microseconds. A graph of peak face stress versus load is illustrated in FIG. 45 for the same three variations just discussed with respect to FIG. 44. FIG. 45 nicely illustrates that incorporation of a crown located SRF (1100) and a sole located SRF (1300) as described herein reduces the peak face stress by almost 25% at the 4000 lbf load level, from a value of 170.4 ksi to 128.1 ksi. The stress reducing feature (1000) permits the use of a very thin face (500) without compromising the integrity of the club head (400). In fact, the face thickness (530) may vary from 0.050 inches, up to 0.120 inches.

Combining the information seen in FIGS. 44 and 45, a new ratio may be developed; namely, a stress-to-deflection ratio of the peak stress on the face to the displacement at a given load, as seen in FIG. 46. In one embodiment, the stress-to-deflection ratio is less than 5000 ksi per inch of deflection, wherein the approximate impact force is applied to the face (500) over a 0.6 inch diameter, centered on the engineered impact point (EIP), and the approximate impact force is at least 1000 lbf and no more than 4000 lbf, the club head volume is less than 300 cc, and the face thickness (530) is less than 0.120 inches. In yet a further embodiment, the face thickness (530) is less than 0.100 inches and the stress-to-deflection ratio is less than 4500 ksi per inch of deflection; while an even further embodiment has a stress-to-deflection ratio that is less than 4300 ksi per inch of deflection.

In addition to the unique stress-to-deflection ratios just discussed, one embodiment of the present invention further includes a face (500) having a characteristic time of at least 220 microseconds and the head volume is less than 200 cubic centimeters. Even further, another embodiment goes even further and incorporates a face (500) having a characteristic time of at least 240 microseconds, a head volume that is less than 170 cubic centimeters, a face height between the maximum top edge height (TEH) and the minimum lower edge (LEH) that is less than 1.50 inches, and a vertical roll radius between 7 inches and 13 inches, which further increases the difficulty in obtaining such a high characteristic time, small face height, and small volume golf club head.

Those skilled in the art know that the characteristic time, often referred to as the CT, value of a golf club head is limited by the equipment rules of the United States Golf Association (USGA). The rules state that the characteristic time of a club head shall not be greater than 239 microseconds, with a maximum test tolerance of 18 microseconds. Thus, it is common for golf clubs to be designed with the goal of a 239 microsecond CT, knowing that due to manufacturing variability that some of the heads will have a CT value higher than 239 microseconds, and some will be lower. However, it is critical that the CT value does not exceed 257 microseconds or the club will not conform to the USGA rules. The USGA publication “Procedure for Measuring the Flexibility of a Golf Clubhead,” Revision 2.0, Mar. 25, 2005, is the current standard that sets forth the procedure for measuring the characteristic time.

With reference now to FIGS. 47-49, another embodiment of the crown located SRF (1100) may include a CSRF aperture (1200) recessed from the crown (600) and extending through the outer shell. As seen in FIG. 49, the CSRF aperture (1200) is located at a CSRF aperture depth (1250) measured vertically from the top edge height (TEH) toward the center of gravity (CG), keeping in mind that the top edge height (TEH) varies across the face (500) from the heel side (406) to the toe side (408). Therefore, as illustrated in FIG. 49, to determine the CSRF aperture depth (1250) one must first take a section in the front-to-rear direction of the club head (400), which establishes the top edge height (TEH) at this particular location on the face (500) that is then used to determine the CSRF aperture depth (1250) at this particular location along the CSRF aperture (1200). For instance, as seen in FIG. 47, the section that is illustrated in FIG. 49 is taken through the center of gravity (CG) location, which is just one of an infinite number of sections that can be taken between the origin and the toewardmost point on the club head (400). Just slightly to the left of the center of gravity (CG) in FIG. 47 is a line representing the face center (FC), if a section such as that of FIG. 49 were taken along the face center (FC) it would illustrate that the top edge height (TEH) is generally the greatest at this point.

At least a portion of the CSRF aperture depth (1250) is greater than zero. This means that at some point along the CSRF aperture (1200), the CSRF aperture (1200) will be located below the elevation of the top of the face (400) directly in front of the point at issue, as illustrated in FIG. 49. In one particular embodiment the CSRF aperture (1200) has a maximum CSRF aperture depth (1250) that is at least ten percent of the Ycg distance. An even further embodiment incorporates a CSRF aperture (1200) that has a maximum CSRF aperture depth (1250) that is at least fifteen percent of the Ycg distance. Incorporation of a CSRF aperture depth (1250) that is greater than zero, and in some embodiments greater than a certain percentage of the Ycg distance, preferably reduces the stress in the face (500) when impacting a golf ball while accommodating temporary flexing and deformation of the crown located SRF (1100) in a stable manner in relation to the CG location, engineered impact point (EIP), and/or outer shell, while maintaining the durability of the face (500) and the crown (600).

The CSRF aperture (1200) has a CSRF aperture width (1240) separating a CSRF leading edge (1220) from a CSRF aperture trailing edge (1230), again measured in a front-to-rear direction as seen in FIG. 49. In one embodiment the CSRF aperture (1200) has a maximum CSRF aperture width (1240) that is at least twenty-five percent of the maximum CSRF aperture depth (1250) to allow preferred flexing and deformation while maintaining durability and stability upon repeated impacts with a golf ball. An even further variation achieves these goals by maintaining a maximum CSRF aperture width (1240) that is less than maximum CSRF aperture depth (1250). In yet another embodiment the CSRF aperture (1200) also has a maximum CSRF aperture width (1240) that is at least fifty percent of a minimum face thickness (530), while optionally also being less than the maximum face thickness (530).

In furtherance of these desirable properties, the CSRF aperture (1200) has a CSRF aperture length (1210) between a CSRF aperture toe-most point (1212) and a CSRF aperture heel-most point (1216) that is at least fifty percent of the Xcg distance. In yet another embodiment the CSRF aperture length (1210) is at least as great as the heel blade length section (Abl), or even further in another embodiment in which the CSRF aperture length (1210) is also at least fifty percent of the blade length (BL).

Referring again to FIG. 49, the CSRF aperture leading edge (1220) has a CSRF aperture leading edge offset (1222). In one embodiment preferred flexing and deformation occur, while maintaining durability, when the minimum CSRF aperture leading edge offset (1222) is at least ten percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH). Even further, another embodiment has found preferred characteristics when the minimum CSRF aperture leading edge offset (1222) at least twenty percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH), and optionally when the maximum CSRF aperture leading edge offset (1222) less than seventy-five percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH).

Again with reference now to FIGS. 47-49 but now turning our attention to the sole located SRF (1300), an embodiment of the sole located SRF (1300) may include a SSRF aperture (1400) recessed from the sole (700) and extending through the outer shell. As seen in FIG. 49, the SSRF aperture (1400) is located at a SSRF aperture depth (1450) measured vertically from the leading edge height (LEH) toward the center of gravity (CG), keeping in mind that the leading edge height (LEH) varies across the face (500) from the heel side (406) to the toe side (408). Therefore, as illustrated in FIG. 49, to determine the SSRF aperture depth (1450) one must first take a section in the front-to-rear direction of the club head (400), which establishes the leading edge height (LEH) at this particular location on the face (500) that is then used to determine the SSRF aperture depth (1450) at this particular location along the SSRF aperture (1400). For instance, as seen in FIG. 47, the section that is illustrated in FIG. 49 is taken through the center of gravity (CG) location, which is just one of an infinite number of sections that can be taken between the origin and the toewardmost point on the club head (400). Just slightly to the left of the center of gravity (CG) in FIG. 47 is a line representing the face center (FC), if a section such as that of FIG. 49 were taken along the face center (FC) it would illustrate that the leading edge height (LEH) is generally the least at this point.

At least a portion of the SSRF aperture depth (1450) is greater than zero. This means that at some point along the SSRF aperture (1400), the SSRF aperture (1400) will be located above the elevation of the bottom of the face (400) directly in front of the point at issue, as illustrated in FIG. 49. In one particular embodiment the SSRF aperture (1400) has a maximum SSRF aperture depth (1450) that is at least ten percent of the Ycg distance. An even further embodiment incorporates a SSRF aperture (1400) that has a maximum SSRF aperture depth (1450) that is at least fifteen percent of the Ycg distance. Incorporation of a SSRF aperture depth (1450) that is greater than zero, and in some embodiments greater than a certain percentage of the Ycg distance, preferably reduces the stress in the face (500) when impacting a golf ball while accommodating temporary flexing and deformation of the sole located SRF (1300) in a stable manner in relation to the CG location, engineered impact point (EIP), and/or outer shell, while maintaining the durability of the face (500) and the sole (700).

The SSRF aperture (1400) has a SSRF aperture width (4240) separating a SSRF leading edge (1420) from a SSRF aperture trailing edge (1430), again measured in a front-to-rear direction as seen in FIG. 49. In one embodiment the SSRF aperture (1400) has a maximum SSRF aperture width (1440) that is at least twenty-five percent of the maximum SSRF aperture depth (1450) to allow preferred flexing and deformation while maintaining durability and stability upon repeated impacts with a golf ball. An even further variation achieves these goals by maintaining a maximum SSRF aperture width (1440) that is less than maximum SSRF aperture depth (1450). In yet another embodiment the SSRF aperture (1400) also has a maximum SSRF aperture width (1440) that is at least fifty percent of a minimum face thickness (530), while optionally also being less than the maximum face thickness (530).

In furtherance of these desirable properties, the SSRF aperture (1400) has a SSRF aperture length (1410) between a SSRF aperture toe-most point (1412) and a SSRF aperture heel-most point (1416) that is at least fifty percent of the Xcg distance. In yet another embodiment the SSRF aperture length (1410) is at least as great as the heel blade length section (Abl), or even further in another embodiment in which the SSRF aperture length (1410) is also at least fifty percent of the blade length (BL).

Referring again to FIG. 49, the SSRF aperture leading edge (1420) has a SSRF aperture leading edge offset (1422). In one embodiment preferred flexing and deformation occur, while maintaining durability, when the minimum SSRF aperture leading edge offset (1422) is at least ten percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH). Even further, another embodiment has found preferred characteristics when the minimum SSRF aperture leading edge offset (1422) at least twenty percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH), and optionally when the maximum SSRF aperture leading edge offset (1422) less than seventy-five percent of the difference between the maximum top edge height (TEH) and the minimum lower edge height (LEH).

As previously discussed, the SRFs (1100, 1300) may be subsequently filled with a secondary material, as seen in FIG. 51, or covered, such that the volume is not visible to a golfer, similarly, the apertures (1200, 1400) may be covered or filled so that they are not noticeable to a user, and so that material and moisture is not unintentionally introduced into the interior of the club head. In other words, one need not be able to view the inside of the club head through the aperture (1200, 1400) in order for the aperture (1200, 1400) to exist. The apertures (1200, 1400) may be covered by a badge extending over the apertures (1200, 1400), or a portion of such cover may extend into the apertures (1200, 1400), as seen in FIG. 52. If a portion of the cover extends into the aperture (1200, 1400) then that portion should be compressible and have a compressive strength that is less than fifty percent of the compressive strength of the outer shell. A badge extending over the aperture (1200, 1400) may be attached to the outer shell on only one side of the aperture (1200, 1400), or on both sides of the aperture (1200, 1400) if the badge is not rigid or utilizes non-rigid connection methods to secure the badge to the outer shell.

The size, location, and configuration of the CSRF aperture (1200) and the SSRF aperture (1400) are selected to preferably reduce the stress in the face (500) when impacting a golf ball while accommodating temporary flexing and deformation of the crown located SRF (1100) and sole located SRF (1300) in a stable manner in relation to the CG location, and/or origin point, while maintaining the durability of the face (500), the crown (600), and the sole (700). While the generally discussed apertures (1200, 1400) of FIGS. 47-49 are illustrated in the bottom wall of the SRF's (1100, 1300), the apertures (1200, 1400) may be located at other locations in the SRF's (1100, 1300) including the front wall as seen in the CSRF aperture (1100) of FIG. 50 and both the CSRF aperture (1200) and SSRF aperture (1400) of FIG. 53, as well as the rear wall as seen in the SSRF aperture (1400) of FIG. 50.

As previously explained, the golf club head (100) has a blade length (BL) that is measured horizontally from the origin point toward the toe side of the golf club head a distance that is parallel to the face and the ground plane (GP) to the most distant point on the golf club head in this direction. In one particular embodiment, the golf club head (100) has a blade length (BL) of at least 3.1 inches, a heel blade length section (Abl) is at least 1.1 inches, and a club moment arm (CMA) of less than 1.3 inches, thereby producing a long blade length golf club having reduced face stress, and improved characteristic time qualities, while not being burdened by the deleterious effects of having a large club moment arm (CMA), as is common in oversized fairway woods. The club moment arm (CMA) has a significant impact on the ball flight of off-center hits. Importantly, a shorter club moment arm (CMA) produces less variation between shots hit at the engineered impact point (EIP) and off-center hits. Thus, a golf ball struck near the heel or toe of the present invention will have launch conditions more similar to a perfectly struck shot. Conversely, a golf ball struck near the heel or toe of an oversized fairway wood with a large club moment arm (CMA) would have significantly different launch conditions than a ball struck at the engineered impact point (EIP) of the same oversized fairway wood. Generally, larger club moment arm (CMA) golf clubs impart higher spin rates on the golf ball when perfectly struck in the engineered impact point (EIP) and produce larger spin rate variations in off-center hits. Therefore, yet another embodiment incorporate a club moment arm (CMA) that is less than 1.1 inches resulting in a golf club with more efficient launch conditions including a lower ball spin rate per degree of launch angle, thus producing a longer ball flight.

Conventional wisdom regarding increasing the Zcg value to obtain club head performance has proved to not recognize that it is the club moment arm (CMA) that plays a much more significant role in golf club performance and ball flight. Controlling the club moments arm (CMA), along with the long blade length (BL), long heel blade length section (Abl), while improving the club head's ability to distribute the stresses of impact and thereby improving the characteristic time across the face, particularly off-center impacts, yields launch conditions that vary significantly less between perfect impacts and off-center impacts than has been seen in the past. In another embodiment, the ratio of the golf club head front-to-back dimension (FB) to the blade length (BL) is less than 0.925, as seen in FIGS. 6 and 13. In this embodiment, the limiting of the front-to-back dimension (FB) of the club head (100) in relation to the blade length (BL) improves the playability of the club, yet still achieves the desired high improvements in characteristic time, face deflection at the heel and toe sides, and reduced club moment arm (CMA). The reduced front-to-back dimension (FB), and associated reduced Zcg, of the present invention also significantly reduces dynamic lofting of the golf club head. Increasing the blade length (BL) of a fairway wood, while decreasing the front-to-back dimension (FB) and incorporating the previously discussed characteristics with respect to the stress reducing feature (1000), minimum heel blade length section (Abl), and maximum club moment arm (CMA), produces a golf club head that has improved playability that would not be expected by one practicing conventional design principles. In yet a further embodiment a unique ratio of the heel blade length section (Abl) to the golf club head front-to-back dimension (FB) has been identified and is at least 0.32. Yet another embodiment incorporates a ratio of the club moment arm (CMA) to the heel blade length section (Abl). In this embodiment the ratio of club moment arm (CMA) to the heel blade length section (Abl) is less than 0.9. Still a further embodiment uniquely characterizes the present fairway wood golf club head with a ratio of the heel blade length section (Abl) to the blade length (BL) that is at least 0.33. A further embodiment has recognized highly beneficial club head performance regarding launch conditions when the transfer distance (TD) is at least 10 percent greater than the club moment arm (CMA). Even further, a particularly effective range for fairway woods has been found to be when the transfer distance (TD) is 10 percent to 40 percent greater than the club moment arm (CMA). This range ensures a high face closing moment (MOIfc) such that bringing club head square at impact feels natural and takes advantage of the beneficial impact characteristics associated with the short club moment arm (CMA) and CG location.

Referring now to FIG. 10, in one embodiment it was found that a particular relationship between the top edge height (TEH) and the Ycg distance further promotes desirable performance and feel. In this embodiment a preferred ratio of the Ycg distance to the top edge height (TEH) is less than 0.40; while still achieving a long blade length of at least 3.1 inches, including a heel blade length section (Abl) that is at least 1.1 inches, a club moment arm (CMA) of less than 1.1 inches, and a transfer distance (TD) of at least 1.2 inches, wherein the transfer distance (TD) is between 10 percent to 40 percent greater than the club moment arm (CMA). This ratio ensures that the CG is below the engineered impact point (EIP), yet still ensures that the relationship between club moment arm (CMA) and transfer distance (TD) are achieved with club head design having a stress reducing feature (1000), a long blade length (BL), and long heel blade length section (Abl). As previously mentioned, as the CG elevation decreases the club moment arm (CMA) increases by definition, thereby again requiring particular attention to maintain the club moment arm (CMA) at less than 1.1 inches while reducing the Ycg distance, and a significant transfer distance (TD) necessary to accommodate the long blade length (BL) and heel blade length section (Abl). In an even further embodiment, a ratio of the Ycg distance to the top edge height (TEH) of less than 0.375 has produced even more desirable ball flight properties. Generally the top edge height (TEH) of fairway wood golf clubs is between 1.1 inches and 2.1 inches.

In fact, most fairway wood type golf club heads fortunate to have a small Ycg distance are plagued by a short blade length (BL), a small heel blade length section (Abl), and/or long club moment arm (CMA). With reference to FIG. 3, one particular embodiment achieves improved performance with the Ycg distance less than 0.65 inches, while still achieving a long blade length of at least 3.1 inches, including a heel blade length section (Abl) that is at least 1.1 inches, a club moment arm (CMA) of less than 1.1 inches, and a transfer distance (TD) of at least 1.2 inches, wherein the transfer distance (TD) is between 10 percent to 40 percent greater than the club moment arm (CMA). As with the prior disclosure, these relationships are a delicate balance among many variables, often going against traditional club head design principles, to obtain desirable performance. Still further, another embodiment has maintained this delicate balance of relationships while even further reducing the Ycg distance to less than 0.60 inches.

As previously touched upon, in the past the pursuit of high MOIy fairway woods led to oversized fairway woods attempting to move the CG as far away from the face of the club, and as low, as possible. With reference again to FIG. 8, this particularly common strategy leads to a large club moment arm (CMA), a variable that the present embodiment seeks to reduce. Further, one skilled in the art will appreciate that simply lowering the CG in FIG. 8 while keeping the Zcg distance, seen in FIGS. 2 and 6, constant actually increases the length of the club moment arm (CMA). The present invention is maintaining the club moment arm (CMA) at less than 1.1 inches to achieve the previously described performance advantages, while reducing the Ycg distance in relation to the top edge height (TEH); which effectively means that the Zcg distance is decreasing and the CG position moves toward the face, contrary to many conventional design goals.

As explained throughout, the relationships among many variables play a significant role in obtaining the desired performance and feel of a golf club. One of these important relationships is that of the club moment arm (CMA) and the transfer distance (TD). One particular embodiment has a club moment arm (CMA) of less than 1.1 inches and a transfer distance (TD) of at least 1.2 inches; however in a further particular embodiment this relationship is even further refined resulting in a fairway wood golf club having a ratio of the club moment arm (CMA) to the transfer distance (TD) that is less than 0.75, resulting in particularly desirable performance. Even further performance improvements have been found in an embodiment having the club moment arm (CMA) at less than 1.0 inch, and even more preferably, less than 0.95 inches. A somewhat related embodiment incorporates a mass distribution that yields a ratio of the Xcg distance to the Ycg distance of at least two.

A further embodiment achieves a Ycg distance of less than 0.65 inches, thereby requiring a very light weight club head shell so that as much discretionary mass as possible may be added in the sole region without exceeding normally acceptable head weights, as well as maintaining the necessary durability. In one particular embodiment this is accomplished by constructing the shell out of a material having a density of less than 5 g/cm³, such as titanium alloy, nonmetallic composite, or thermoplastic material, thereby permitting over one-third of the final club head weight to be discretionary mass located in the sole of the club head. One such nonmetallic composite may include composite material such as continuous fiber pre-preg material (including thermosetting materials or thermoplastic materials for the resin). In yet another embodiment the discretionary mass is composed of a second material having a density of at least 15 g/cm³, such as tungsten. An even further embodiment obtains a Ycg distance is less than 0.55 inches by utilizing a titanium alloy shell and at least 80 grams of tungsten discretionary mass, all the while still achieving a ratio of the Ycg distance to the top edge height (TEH) is less than 0.40, a blade length (BL) of at least 3.1 inches with a heel blade length section (Abl) that is at least 1.1 inches, a club moment arm (CMA) of less than 1.1 inches, and a transfer distance (TD) of at least 1.2 inches.

A further embodiment recognizes another unusual relationship among club head variables that produces a fairway wood type golf club exhibiting exceptional performance and feel. In this embodiment it has been discovered that a heel blade length section (Abl) that is at least twice the Ycg distance is desirable from performance, feel, and aesthetics perspectives. Even further, a preferably range has been identified by appreciating that performance, feel, and aesthetics get less desirable as the heel blade length section (Abl) exceeds 2.75 times the Ycg distance. Thus, in this one embodiment the heel blade length section (Abl) should be 2 to 2.75 times the Ycg distance.

Similarly, a desirable overall blade length (BL) has been linked to the Ycg distance. In yet another embodiment preferred performance and feel is obtained when the blade length (BL) is at least 6 times the Ycg distance. Such relationships have not been explored with conventional golf clubs because exceedingly long blade lengths (BL) would have resulted. Even further, a preferable range has been identified by appreciating that performance and feel become less desirable as the blade length (BL) exceeds 7 times the Ycg distance. Thus, in this one embodiment the blade length (BL) should be 6 to 7 times the Ycg distance.

Just as new relationships among blade length (BL) and Ycg distance, as well as the heel blade length section (Abl) and Ycg distance, have been identified; another embodiment has identified relationships between the transfer distance (TD) and the Ycg distance that produce a particularly playable golf club. One embodiment has achieved preferred performance and feel when the transfer distance (TD) is at least 2.25 times the Ycg distance. Even further, a preferable range has been identified by appreciating that performance and feel deteriorate when the transfer distance (TD) exceeds 2.75 times the Ycg distance. Thus, in yet another embodiment the transfer distance (TD) should be within the relatively narrow range of 2.25 to 2.75 times the Ycg distance for preferred performance and feel.

All the ratios used in defining embodiments of the present invention involve the discovery of unique relationships among key club head engineering variables that are inconsistent with merely striving to obtain a high MOIy or low CG using conventional golf club head design wisdom. 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 invention. Further, 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 invention 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 invention as defined in the following claims.

Claims

1. An iron-type golf club head (400) comprising: (i) a face (500) positioned at a front portion (402) of the golf club head (400) where the golf club head (400) impacts a golf ball, opposite a rear portion (404) of the golf club head (400), wherein the face (500) includes an engineered impact point (EIP), a face height, a top edge height (TEH), and a lower edge height (LEH), wherein the face (500) has a blade length (BL) measured horizontally from an origin point toward a toe side (408) of the golf club head (400) to the most distant point on the golf club head (400) in this direction, wherein the blade length (BL) includes a toe blade length section (Bbl) and a heel blade length section (Abl) measured in the same direction as the blade length (BL) from the origin point to the engineered impact point (EIP);(ii) a sole (700) positioned at a bottom portion of the golf club head (400);(iii) a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define the origin point, wherein the bore is located at a heel side (406) of the golf club head (400), and wherein the toe side (408) of the golf club head (400) is located opposite of the heel side (406);(iv) a center of gravity (CG) located: (a) vertically from the origin point a distance Ycg;(b) horizontally from the origin point toward the toe side (408) of the golf club head (400) a distance Xcg; and(c) a distance Zcg from the origin toward the rear portion (404) in a direction generally orthogonal to the vertical direction used to measure Ycg and generally orthogonal to the horizontal direction used to measure Xcg; and(v) a stress reducing feature (1000) including a sole located SRF (1300) located at least partially on the sole (700), wherein the sole located SRF (1300) has a SSRF length (1310) that is at least as great as the heel blade length section (Abl), a SSRF leading edge (1320) having a SSRF leading edge offset (1322), a SSRF width (1340), a SSRF depth (1350, and a SSRF front wall spaced away from a rear surface of the face (500) by a void, wherein at least one point along the SSRF length (1310) has the SSRF width (1340) of at least ten percent of the Zcg distance and at least one point along the SSRF length (1310) has the SSRF depth (1350) of at least ten percent of the Ycg distance.
2. The iron-type golf club head (400) of claim 1, wherein at least a portion of the SSRF leading edge (1320) is located behind a plane defined by the shaft axis (SA) and the Xcg direction.
3. The iron-type golf club head (400) of claim 1, wherein the sole located SRF (1300) has a SSRF cross-sectional area (1370), and the SSRF cross-sectional area (1370) is not constant over the SSRF length (1310).
4. The iron-type golf club head (400) of claim 1, wherein at least one point along the SSRF length (1310) has the SSRF depth (1350) of at least at least twenty percent of the face height.
5. The iron-type golf club head (400) of claim 1, wherein the sole located SRF (1300) has a SSRF aperture (1400) recessed from the sole (700) and extending through a portion of the sole located SRF (1300), wherein the SSRF aperture (1400) is located at a SSRF aperture depth (1450) measured vertically from the lower edge height (LEH) toward the center of gravity (CG), wherein at least one point of the SSRF aperture (1400) has the SSRF aperture depth (1450) of at least ten percent of the Ycg distance, and the SSRF aperture (1400) has a SSRF aperture length (1410), and a SSRF aperture width (1440).
6. The iron-type golf club head (400) of claim 5, the SSRF aperture length (1410) is at least fifty percent of the Xcg distance.
7. The iron-type golf club head (400) of claim 6, the SSRF aperture length (1410) is at least as great as the heel blade length section (Abl).
8. The iron-type golf club head (400) of claim 5, wherein at least one point of the SSRF aperture (1400) has the SSRF aperture depth (1450) of at least fifteen percent of the Ycg distance.
9. The iron-type golf club head (400) of claim 5, wherein at least one point of the SSRF aperture (1400) has a SSRF aperture width (1440) that is at least fifty percent of a minimum face thickness (530).
10. The iron-type golf club head (400) of claim 9, wherein the SSRF aperture (1400) has a maximum SSRF aperture width (1440) that is less than the maximum face thickness (530).
11. The iron-type golf club head (400) of claim 5, wherein at least one point of the SSRF aperture (1400) has the SSRF aperture width (1440) of at least twenty-five percent of the maximum SSRF aperture depth (1450).
12. The iron-type golf club head (400) of claim 5, wherein the maximum SSRF aperture width (1440) is less than the maximum SSRF aperture depth (1450).
13. The iron-type golf club head (400) of claim 5, wherein the SSRF aperture (1400) is located in the SSRF front wall.
14. The iron-type golf club head (400) of claim 5, wherein stress reducing feature (1000) has a SSRF bottom wall and the SSRF aperture (1400) is located in the SSRF bottom wall.
15. The iron-type golf club head (400) of claim 5, wherein stress reducing feature (1000) has a SSRF rear wall and the SSRF aperture (1400) is located in the SSRF rear wall.
16. An iron-type golf club head (400) comprising: (i) a face (500) positioned at a front portion (402) of the golf club head (400) where the golf club head (400) impacts a golf ball, opposite a rear portion (404) of the golf club head (400), wherein the face (500) includes an engineered impact point (EIP), a face height, a top edge height (TEH), and a lower edge height (LEH), wherein the face (500) has a blade length (BL) measured horizontally from an origin point toward a toe side (408) of the golf club head (400) to the most distant point on the golf club head (400) in this direction, wherein the blade length (BL) includes a toe blade length section (Bbl) and a heel blade length section (Abl) measured in the same direction as the blade length (BL) from the origin point to the engineered impact point (EIP);(ii) a sole (700) positioned at a bottom portion of the golf club head (400);(iii) a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define the origin point, wherein the bore is located at a heel side (406) of the golf club head (400), and wherein the toe side (408) of the golf club head (400) is located opposite of the heel side (406);(iv) a center of gravity (CG) located: (a) vertically from the origin point a distance Ycg;(b) horizontally from the origin point toward the toe side (408) of the golf club head (400) a distance Xcg; and(c) a distance Zcg from the origin toward the rear portion (404) in a direction generally orthogonal to the vertical direction used to measure Ycg and generally orthogonal to the horizontal direction used to measure Xcg;(v) a stress reducing feature (1000) including a sole located SRF (1300) located at least partially on the sole (700), wherein the sole located SRF (1300) has a SSRF length (1310) that is at least as great as the heel blade length section (Abl), a SSRF leading edge (1320) having a SSRF leading edge offset (1322), a SSRF width (1340), a SSRF depth (1350, and a SSRF front wall spaced away from a rear surface of the face (500) by a void, wherein at least one point along the SSRF length (1310) has the SSRF width (1340) of at least ten percent of the Zcg distance and at least one point along the SSRF length (1310) has the SSRF depth (1350) of at least ten percent of the Ycg distance; and(vi) the sole located SRF (1300) has a SSRF aperture (1400) recessed from the sole (700) and extending through a portion of the sole located SRF (1300), wherein the SSRF aperture (1400) is located at a SSRF aperture depth (1450) measured vertically from the lower edge height (LEH) toward the center of gravity (CG), wherein at least one point of the SSRF aperture (1400) has the SSRF aperture depth (1450) of at least ten percent of the Ycg distance, and the SSRF aperture (1400) has a SSRF aperture length (1410), and a SSRF aperture width (1440).
17. The iron-type golf club head (400) of claim 16, wherein at least a portion of the SSRF leading edge (1320) is located behind a plane defined by the shaft axis (SA) and the Xcg direction.
18. The iron-type golf club head (400) of claim 16, wherein at least one point along the SSRF length (1310) has the SSRF depth (1350) of at least at least twenty percent of the face height.
19. The iron-type golf club head (400) of claim 16, the SSRF aperture length (1410) is at least fifty percent of the Xcg distance.
20. The iron-type golf club head (400) of claim 16, wherein at least one point of the SSRF aperture (1400) has a SSRF aperture width (1440) that is at least fifty percent of a minimum face thickness (530).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 14/472,415, filed on Aug. 29, 2014, which is a continuation of U.S. patent application Ser. No. 13/397,122, now U.S. Pat. No. 8,821,312, filed on Feb. 15, 2012, which is a continuation-in-part of U.S. patent application Ser. No. 12/791,025, now U.S. Pat. No. 8,235,844, filed on Jun. 1, 2010, all of which is incorporated by reference as if completely written herein.

US Referenced Citations (722)

Number	Name	Date	Kind
411000	Anderson	Sep 1889	A
708575	Mules	Sep 1902	A
727819	Mattern	May 1903	A
819900	Martin	May 1906	A
1133129	Govan	Mar 1915	A
1518316	Ellingham	Dec 1924	A
1526438	Scott	Feb 1925	A
1538312	Beat	May 1925	A
1592463	Marker	Jul 1926	A
1658581	Tobia	Feb 1928	A
1704119	Buhrke	Mar 1929	A
1705997	Williams	Mar 1929	A
1970409	Wiedemann	Aug 1934	A
2004968	Young	Jun 1935	A
2034936	Barnhart	Mar 1936	A
D107007	Cashmore	Nov 1937	S
2198981	Sullivan	Apr 1940	A
2214356	Wettlaufer	Sep 1940	A
2225930	Sexton	Dec 1940	A
2328583	Reach	Sep 1943	A
2332342	Reach	Oct 1943	A
2360364	Reach	Oct 1944	A
2375249	Richer	May 1945	A
2460435	Schaffer	Feb 1949	A
2681523	Sellers	Jun 1954	A
2968486	Jackson	Jan 1961	A
3064980	Steiner	Nov 1962	A
3084940	Cissel	Apr 1963	A
3085804	Pieper	Apr 1963	A
3166320	Onions	Jan 1965	A
3466047	Rodia et al.	Sep 1969	A
3486755	Hodge	Dec 1969	A
3556533	Hollis	Jan 1971	A
3589731	Chancellor	Jun 1971	A
3606327	Gorman	Sep 1971	A
3610630	Glover	Oct 1971	A
3652094	Glover	Mar 1972	A
3672419	Fischer	Jun 1972	A
3692306	Glover	Sep 1972	A
3743297	Dennis	Jul 1973	A
3860244	Cosby	Jan 1975	A
3893672	Schonher	Jul 1975	A
3897066	Belmont	Jul 1975	A
3970236	Rogers	Jul 1976	A
3976299	Lawrence et al.	Aug 1976	A
3979122	Belmont	Sep 1976	A
3979123	Belmont	Sep 1976	A
3985363	Jepson et al.	Oct 1976	A
3997170	Goldberg	Dec 1976	A
4008896	Gordos	Feb 1977	A
4027885	Rogers	Jun 1977	A
4043563	Churchward	Aug 1977	A
4052075	Daly	Oct 1977	A
4065133	Gordos	Dec 1977	A
4076254	Nygren	Feb 1978	A
4077633	Studen	Mar 1978	A
4085934	Churchward	Apr 1978	A
4121832	Ebbing	Oct 1978	A
4139196	Riley	Feb 1979	A
4147349	Jeghers	Apr 1979	A
4150702	Holmes	Apr 1979	A
4165076	Cella	Aug 1979	A
4189976	Becker	Feb 1980	A
4193601	Reid, Jr. et al.	Mar 1980	A
4214754	Zebelean	Jul 1980	A
D256709	Reid, Jr. et al.	Sep 1980	S
4247105	Jeghers	Jan 1981	A
4262562	MacNeill	Apr 1981	A
D259698	MacNeill	Jun 1981	S
4322083	Imai	Mar 1982	A
4340229	Stuff, Jr.	Jul 1982	A
4398965	Campau	Aug 1983	A
4411430	Dian	Oct 1983	A
4423874	Stuff, Jr.	Jan 1984	A
4431192	Stuff, Jr.	Feb 1984	A
4432549	Zebelean	Feb 1984	A
4438931	Motomiya	Mar 1984	A
4471961	Masghati et al.	Sep 1984	A
4489945	Kobayashi	Dec 1984	A
4527799	Solheim	Jul 1985	A
4530505	Stuff	Jul 1985	A
D284346	Masters	Jun 1986	S
4592552	Garber	Jun 1986	A
4602787	Sugioka et al.	Jul 1986	A
4607846	Perkins	Aug 1986	A
D285473	Flood	Sep 1986	S
4712798	Preato	Dec 1987	A
4730830	Tilley	Mar 1988	A
4736093	Braly	Apr 1988	A
4754974	Kobayashi	Jul 1988	A
4754977	Sahm	Jul 1988	A
4762322	Molitor et al.	Aug 1988	A
4787636	Honma	Nov 1988	A
4795159	Nagamoto	Jan 1989	A
4803023	Enomoto et al.	Feb 1989	A
4809983	Langert	Mar 1989	A
4867457	Lowe	Sep 1989	A
4867458	Sumikawa et al.	Sep 1989	A
4869507	Sahm	Sep 1989	A
4881739	Garcia	Nov 1989	A
4890840	Kobayashi	Jan 1990	A
4895367	Kajita et al.	Jan 1990	A
4895371	Bushner	Jan 1990	A
4915558	Muller	Apr 1990	A
4919428	Perkins	Apr 1990	A
4962932	Anderson	Oct 1990	A
4994515	Washiyama et al.	Feb 1991	A
5006023	Kaplan	Apr 1991	A
5020950	Ladouceur	Jun 1991	A
5028049	McKeighen	Jul 1991	A
5039267	Wollar	Aug 1991	A
5042806	Helmstetter	Aug 1991	A
5050879	Sun et al.	Sep 1991	A
5058895	Igarashi	Oct 1991	A
5076585	Bouquet	Dec 1991	A
D323035	Yang	Jan 1992	S
5078400	Desbiolles et al.	Jan 1992	A
5092599	Okumoto et al.	Mar 1992	A
5116054	Johnson	May 1992	A
5121922	Harsh, Sr.	Jun 1992	A
5122020	Bedi	Jun 1992	A
5172913	Bouquet	Dec 1992	A
5190289	Nagai et al.	Mar 1993	A
5193810	Antonious	Mar 1993	A
5203565	Murray et al.	Apr 1993	A
5221086	Antonious	Jun 1993	A
5232224	Zeider	Aug 1993	A
5244210	Au	Sep 1993	A
5251901	Solheim et al.	Oct 1993	A
5253869	Dingle et al.	Oct 1993	A
5255919	Johnson	Oct 1993	A
D343558	Latraverse et al.	Jan 1994	S
5297794	Lu	Mar 1994	A
5301944	Koehler	Apr 1994	A
5306008	Kinoshita	Apr 1994	A
5316305	McCabe	May 1994	A
5318297	Davis et al.	Jun 1994	A
5320005	Hsiao	Jun 1994	A
5328176	Lo	Jul 1994	A
5340106	Ravaris	Aug 1994	A
5346216	Aizawa	Sep 1994	A
5346217	Tsuchiya et al.	Sep 1994	A
5385348	Wargo	Jan 1995	A
5395113	Antonious	Mar 1995	A
5410798	Lo	May 1995	A
5419556	Take	May 1995	A
5421577	Kobayashi	Jun 1995	A
5429365	McKeighen	Jul 1995	A
5437456	Schmidt et al.	Aug 1995	A
5439222	Kranenberg	Aug 1995	A
5441274	Clay	Aug 1995	A
5447309	Vincent	Sep 1995	A
5449260	Whittle	Sep 1995	A
D365615	Shimatani	Dec 1995	S
D366508	Hutin	Jan 1996	S
5482280	Yamawaki	Jan 1996	A
5492327	Biafore, Jr.	Feb 1996	A
5511786	Antonious	Apr 1996	A
5518243	Redman	May 1996	A
5533730	Ruvang	Jul 1996	A
D372512	Simmons	Aug 1996	S
5558332	Cook	Sep 1996	A
D375130	Hlinka et al.	Oct 1996	S
5564705	Kobayashi et al.	Oct 1996	A
5571053	Lane	Nov 1996	A
5573467	Chou et al.	Nov 1996	A
5582553	Ashcraft et al.	Dec 1996	A
D377509	Katayama	Jan 1997	S
5613917	Kobayashi et al.	Mar 1997	A
D378770	Hlinka et al.	Apr 1997	S
5616088	Aizawa et al.	Apr 1997	A
5620379	Borys	Apr 1997	A
5624331	Lo et al.	Apr 1997	A
5629475	Chastonay	May 1997	A
5632694	Lee	May 1997	A
5632695	Hlinka et al.	May 1997	A
D382612	Oyer	Aug 1997	S
5658206	Antonious	Aug 1997	A
5669827	Nagamoto	Sep 1997	A
5681228	Mikame et al.	Oct 1997	A
5683309	Reimers	Nov 1997	A
5688189	Bland	Nov 1997	A
5695412	Cook	Dec 1997	A
5700208	Nelms	Dec 1997	A
5709613	Sheraw	Jan 1998	A
5718641	Lin	Feb 1998	A
5720674	Galy	Feb 1998	A
D392526	Nicely	Mar 1998	S
5735754	Antonious	Apr 1998	A
D394688	Fox	May 1998	S
5746664	Reynolds, Jr.	May 1998	A
5749795	Schmidt	May 1998	A
5755627	Yamazaki et al.	May 1998	A
5759114	Bluto et al.	Jun 1998	A
5762567	Antonious	Jun 1998	A
5766095	Antonious	Jun 1998	A
5769737	Holladay et al.	Jun 1998	A
5772527	Liu	Jun 1998	A
5776010	Helmstetter et al.	Jul 1998	A
5776011	Su et al.	Jul 1998	A
5785608	Collins	Jul 1998	A
5788587	Tseng	Aug 1998	A
5797807	Moore	Aug 1998	A
5798587	Lee	Aug 1998	A
D397750	Frazetta	Sep 1998	S
RE35955	Lu	Nov 1998	E
5830084	Kosmatka	Nov 1998	A
D403037	Stone et al.	Dec 1998	S
5851160	Rugge et al.	Dec 1998	A
D405488	Burrows	Feb 1999	S
5876293	Musty	Mar 1999	A
5885166	Shiraishi	Mar 1999	A
5890971	Shiraishi	Apr 1999	A
D409463	McMullin	May 1999	S
5908356	Nagamoto	Jun 1999	A
5911638	Parente et al.	Jun 1999	A
5913735	Kenmi	Jun 1999	A
5916042	Reimers	Jun 1999	A
D412547	Fong	Aug 1999	S
5935019	Yamamoto	Aug 1999	A
5935020	Stites et al.	Aug 1999	A
5941782	Cook	Aug 1999	A
D413952	Oyer	Sep 1999	S
5947840	Ryan	Sep 1999	A
5954595	Antonious	Sep 1999	A
5967905	Nakahara et al.	Oct 1999	A
5971867	Galy	Oct 1999	A
5976033	Takeda	Nov 1999	A
5997415	Wood	Dec 1999	A
6001029	Kobayashi	Dec 1999	A
6015354	Ahn et al.	Jan 2000	A
6017177	Lanham	Jan 2000	A
6019686	Gray	Feb 2000	A
6023891	Robertson et al.	Feb 2000	A
6032677	Blechman et al.	Mar 2000	A
6033318	Drajan, Jr. et al.	Mar 2000	A
6033319	Farrar	Mar 2000	A
6033321	Yamamoto	Mar 2000	A
6042486	Gallagher	Mar 2000	A
6048278	Meyer et al.	Apr 2000	A
6056649	Imai	May 2000	A
6062988	Yamamoto	May 2000	A
6074308	Domas	Jun 2000	A
6077171	Yoneyama	Jun 2000	A
6083115	King	Jul 2000	A
6086485	Hamada	Jul 2000	A
6089994	Sun	Jul 2000	A
6093113	Mertens	Jul 2000	A
6123627	Antonious	Sep 2000	A
6139445	Werner et al.	Oct 2000	A
6146286	Masuda	Nov 2000	A
6149533	Finn	Nov 2000	A
6162132	Yoneyama	Dec 2000	A
6162133	Peterson	Dec 2000	A
6168537	Ezawa	Jan 2001	B1
6171204	Starry	Jan 2001	B1
6186905	Kosmatka	Feb 2001	B1
6190267	Marlowe et al.	Feb 2001	B1
6193614	Sasamoto et al.	Feb 2001	B1
6203448	Yamamoto	Mar 2001	B1
6206789	Takeda	Mar 2001	B1
6206790	Kubica et al.	Mar 2001	B1
6210290	Erickson et al.	Apr 2001	B1
6217461	Galy	Apr 2001	B1
6238303	Fite	May 2001	B1
6244974	Hanberry, Jr.	Jun 2001	B1
6244976	Murphy et al.	Jun 2001	B1
6248025	Murphey et al.	Jun 2001	B1
6254494	Hasebe et al.	Jul 2001	B1
6264414	Hartmann et al.	Jul 2001	B1
6270422	Fisher	Aug 2001	B1
6277032	Smith	Aug 2001	B1
6290609	Takeda	Sep 2001	B1
6296579	Robinson	Oct 2001	B1
6299547	Kosmatka	Oct 2001	B1
6306048	McCabe et al.	Oct 2001	B1
6319149	Lee	Nov 2001	B1
6319150	Werner et al.	Nov 2001	B1
6325728	Helmstetter et al.	Dec 2001	B1
6332847	Murphy et al.	Dec 2001	B2
6334817	Ezawa et al.	Jan 2002	B1
6334818	Cameron et al.	Jan 2002	B1
6338683	Kosmatka	Jan 2002	B1
6340337	Hasebe et al.	Jan 2002	B2
6344000	Hamada	Feb 2002	B1
6344001	Hamada	Feb 2002	B1
6344002	Kajita	Feb 2002	B1
6348012	Erickson et al.	Feb 2002	B1
6348013	Kosmatka	Feb 2002	B1
6348014	Chiu	Feb 2002	B1
6354962	Galloway et al.	Mar 2002	B1
6364788	Helmstetter et al.	Apr 2002	B1
6368232	Hamada	Apr 2002	B1
6368234	Galloway	Apr 2002	B1
6371868	Galloway et al.	Apr 2002	B1
6379264	Forzano	Apr 2002	B1
6379265	Hirakawa et al.	Apr 2002	B1
6383090	ODoherty et al.	May 2002	B1
6386987	Lejeune, Jr.	May 2002	B1
6386990	Reyes et al.	May 2002	B1
6390933	Galloway et al.	May 2002	B1
6398666	Evans et al.	Jun 2002	B1
6406378	Murphy et al.	Jun 2002	B1
6409612	Evans et al.	Jun 2002	B1
6425832	Cackett et al.	Jul 2002	B2
6434811	Helmstetter et al.	Aug 2002	B1
6435977	Helmstetter et al.	Aug 2002	B1
6436142	Paes et al.	Aug 2002	B1
6440008	Murphy et al.	Aug 2002	B2
6440009	Guibaud et al.	Aug 2002	B1
6440010	Deshmukh	Aug 2002	B1
6443851	Liberatore	Sep 2002	B1
6458042	Chen	Oct 2002	B1
6458044	Vincent et al.	Oct 2002	B1
6461249	Liberatore	Oct 2002	B2
6464598	Miller	Oct 2002	B1
6471604	Hocknell et al.	Oct 2002	B2
6475101	Burrows	Nov 2002	B2
6475102	Helmstetter et al.	Nov 2002	B2
6478692	Kosmatka	Nov 2002	B2
6482106	Saso	Nov 2002	B2
6491592	Cackett et al.	Dec 2002	B2
6508978	Deshmukh	Jan 2003	B1
6514154	Finn	Feb 2003	B1
6524194	McCabe	Feb 2003	B2
6524197	Boone	Feb 2003	B2
6524198	Takeda	Feb 2003	B2
6527649	Neher et al.	Mar 2003	B1
6527650	Reyes et al.	Mar 2003	B2
6530847	Antonious	Mar 2003	B1
6530848	Gillig	Mar 2003	B2
6533679	McCabe et al.	Mar 2003	B1
6547676	Cackett et al.	Apr 2003	B2
6558273	Kobayashi et al.	May 2003	B2
6565448	Cameron	May 2003	B2
6565452	Helmstetter et al.	May 2003	B2
6569029	Hamburger	May 2003	B1
6569040	Bradstock	May 2003	B2
6572489	Miyamoto et al.	Jun 2003	B2
6575845	Galloway et al.	Jun 2003	B2
6582323	Soracco et al.	Jun 2003	B2
6592466	Helmstetter et al.	Jul 2003	B2
6592468	Vincent et al.	Jul 2003	B2
6602149	Jacobson	Aug 2003	B1
6605007	Bissonnette et al.	Aug 2003	B1
6607452	Helmstetter et al.	Aug 2003	B2
6612398	Tokimatsu et al.	Sep 2003	B1
6616547	Vincent et al.	Sep 2003	B2
6620056	Galloway et al.	Sep 2003	B2
6638180	Tsurumaki	Oct 2003	B2
6638183	Takeda	Oct 2003	B2
D482089	Burrows	Nov 2003	S
D482090	Burrows	Nov 2003	S
D482420	Burrows	Nov 2003	S
6641487	Hamburger	Nov 2003	B1
6641490	Ellemor	Nov 2003	B2
6648772	Vincent et al.	Nov 2003	B2
6648773	Evans	Nov 2003	B1
6652387	Liberatore	Nov 2003	B2
D484208	Burrows	Dec 2003	S
6663504	Hocknell et al.	Dec 2003	B2
6663506	Nishimoto et al.	Dec 2003	B2
6669571	Cameron et al.	Dec 2003	B1
6669576	Rice	Dec 2003	B1
6669577	Hocknell et al.	Dec 2003	B1
6669578	Evans	Dec 2003	B1
6669580	Cackett et al.	Dec 2003	B1
6676536	Jacobson	Jan 2004	B1
6679786	McCabe	Jan 2004	B2
D486542	Burrows	Feb 2004	S
6695712	Iwata et al.	Feb 2004	B1
6716111	Liberatore	Apr 2004	B2
6716114	Nishio	Apr 2004	B2
6719510	Cobzaru	Apr 2004	B2
6719641	Dabbs et al.	Apr 2004	B2
6719645	Kouno	Apr 2004	B2
6723002	Barlow	Apr 2004	B1
6739982	Murphy et al.	May 2004	B2
6739983	Helmstetter et al.	May 2004	B2
6743118	Soracco	Jun 2004	B1
6749523	Forzano	Jun 2004	B1
6757572	Forest	Jun 2004	B1
6758763	Murphy et al.	Jul 2004	B2
6766726	Schwarzkopf	Jul 2004	B1
6773359	Lee	Aug 2004	B1
6773360	Willett et al.	Aug 2004	B2
6773361	Lee	Aug 2004	B1
6776723	Bliss et al.	Aug 2004	B2
6776726	Sano	Aug 2004	B2
6783465	Matsunaga	Aug 2004	B2
6800038	Willett et al.	Oct 2004	B2
6800040	Galloway et al.	Oct 2004	B2
6805643	Lin	Oct 2004	B1
6808460	Namiki	Oct 2004	B2
6811496	Wahl et al.	Nov 2004	B2
6821214	Rice	Nov 2004	B2
6824475	Burnett et al.	Nov 2004	B2
6835145	Tsurumaki	Dec 2004	B2
D501036	Burrows	Jan 2005	S
D501523	Dogan et al.	Feb 2005	S
D501903	Tanaka	Feb 2005	S
6855068	Antonious	Feb 2005	B2
6860818	Mahaffey et al.	Mar 2005	B2
6860823	Lee	Mar 2005	B2
6860824	Evans	Mar 2005	B2
D504478	Burrows	Apr 2005	S
6875124	Gilbert et al.	Apr 2005	B2
6875129	Erickson et al.	Apr 2005	B2
6875130	Nishio	Apr 2005	B2
6881158	Yang et al.	Apr 2005	B2
6881159	Galloway et al.	Apr 2005	B2
6887165	Tsurumaki	May 2005	B2
6890267	Mahaffey et al.	May 2005	B2
D506236	Evans et al.	Jun 2005	S
6902497	Deshmukh et al.	Jun 2005	B2
6904663	Willett et al.	Jun 2005	B2
D508274	Burrows	Aug 2005	S
D508275	Burrows	Aug 2005	S
6923734	Meyer	Aug 2005	B2
6926619	Helmstetter et al.	Aug 2005	B2
6932717	Hou et al.	Aug 2005	B2
6960142	Bissonnette et al.	Nov 2005	B2
6964617	Williams	Nov 2005	B2
6974393	Caldwell et al.	Dec 2005	B2
6988960	Mahaffey et al.	Jan 2006	B2
6991558	Beach et al.	Jan 2006	B2
D515165	Zimmerman et al.	Feb 2006	S
6994636	Hocknell et al.	Feb 2006	B2
6994637	Murphy et al.	Feb 2006	B2
6997820	Willett et al.	Feb 2006	B2
7004849	Cameron	Feb 2006	B2
7004852	Billings	Feb 2006	B2
7025692	Erickson et al.	Apr 2006	B2
7029403	Rice et al.	Apr 2006	B2
D520585	Hasebe	May 2006	S
D523104	Hasebe	Jun 2006	S
7070512	Nishio	Jul 2006	B2
7070517	Cackett et al.	Jul 2006	B2
7077762	Kouno et al.	Jul 2006	B2
7082665	Deshmukh et al.	Aug 2006	B2
7097572	Yabu	Aug 2006	B2
7101289	Gibbs et al.	Sep 2006	B2
7112148	Deshmukh	Sep 2006	B2
7118493	Galloway	Oct 2006	B2
7121957	Hocknell et al.	Oct 2006	B2
7125344	Hocknell et al.	Oct 2006	B2
7128661	Soracco et al.	Oct 2006	B2
7134971	Franklin et al.	Nov 2006	B2
7137905	Kohno	Nov 2006	B2
7137906	Tsunoda et al.	Nov 2006	B2
7137907	Gibbs et al.	Nov 2006	B2
7140974	Chao et al.	Nov 2006	B2
7144334	Ehlers et al.	Dec 2006	B2
7147572	Kohno	Dec 2006	B2
7147573	DiMarco	Dec 2006	B2
7153220	Lo	Dec 2006	B2
7156750	Nishitani et al.	Jan 2007	B2
7163468	Gibbs et al.	Jan 2007	B2
7163470	Galloway et al.	Jan 2007	B2
7166038	Williams et al.	Jan 2007	B2
7166040	Hoffman et al.	Jan 2007	B2
7166041	Evans	Jan 2007	B2
7169058	Fagan	Jan 2007	B1
7169060	Stevens et al.	Jan 2007	B2
D536402	Kawami	Feb 2007	S
7179034	Ladouceur	Feb 2007	B2
7186190	Beach et al.	Mar 2007	B1
7189169	Billings	Mar 2007	B2
7198575	Beach et al.	Apr 2007	B2
7201669	Stites et al.	Apr 2007	B2
D543600	Oldknow	May 2007	S
7211005	Lindsay	May 2007	B2
7211006	Chang	May 2007	B2
7214143	Deshmukh	May 2007	B2
7223180	Willett et al.	May 2007	B2
D544939	Radcliffe et al.	Jun 2007	S
7226366	Galloway	Jun 2007	B2
7250007	Lu	Jul 2007	B2
7252600	Murphy et al.	Aug 2007	B2
7255654	Murphy et al.	Aug 2007	B2
7258626	Gibbs et al.	Aug 2007	B2
7258631	Galloway et al.	Aug 2007	B2
7267620	Chao et al.	Sep 2007	B2
7273423	Imamoto	Sep 2007	B2
D552701	Ruggiero et al.	Oct 2007	S
7278927	Gibbs et al.	Oct 2007	B2
7281985	Galloway	Oct 2007	B2
D554720	Barez et al.	Nov 2007	S
7291074	Kouno et al.	Nov 2007	B2
7294064	Tsurumaki	Nov 2007	B2
7294065	Liang et al.	Nov 2007	B2
7297072	Meyer et al.	Nov 2007	B2
7303488	Kakiuchi et al.	Dec 2007	B2
7306527	Williams et al.	Dec 2007	B2
7314418	Galloway et al.	Jan 2008	B2
7318782	Imamoto et al.	Jan 2008	B2
7320646	Galloway	Jan 2008	B2
D561286	Morales et al.	Feb 2008	S
7344452	Imamoto et al.	Mar 2008	B2
7347795	Yamgishi et al.	Mar 2008	B2
7354355	Tavares et al.	Apr 2008	B2
7377860	Breier et al.	May 2008	B2
7387577	Murphy et al.	Jun 2008	B2
7390266	Gwon	Jun 2008	B2
7396293	Soracco	Jul 2008	B2
7396296	Evans	Jul 2008	B2
7402112	Galloway	Jul 2008	B2
7407447	Beach et al.	Aug 2008	B2
7407448	Stevens et al.	Aug 2008	B2
7413520	Hocknell et al.	Aug 2008	B1
D577090	Pergande et al.	Sep 2008	S
7419441	Hoffman et al.	Sep 2008	B2
D579507	Llewellyn et al.	Oct 2008	S
7431667	Vincent et al.	Oct 2008	B2
7438647	Hocknell	Oct 2008	B1
7438649	Ezaki et al.	Oct 2008	B2
7448963	Beach et al.	Nov 2008	B2
7455598	Williams et al.	Nov 2008	B2
7470201	Nakahara et al.	Dec 2008	B2
D584784	Barez et al.	Jan 2009	S
7476161	Williams et al.	Jan 2009	B2
7491134	Murphy et al.	Feb 2009	B2
D588223	Kuan	Mar 2009	S
7497787	Murphy et al.	Mar 2009	B2
7500924	Yokota	Mar 2009	B2
7520820	Dimarco	Apr 2009	B2
D592723	Chau et al.	May 2009	S
7530901	Imamoto et al.	May 2009	B2
7530904	Beach et al.	May 2009	B2
7540811	Beach et al.	Jun 2009	B2
7549933	Kumamoto	Jun 2009	B2
7549935	Foster et al.	Jun 2009	B2
7563175	Nishitani et al.	Jul 2009	B2
7568985	Beach et al.	Aug 2009	B2
7572193	Yokota	Aug 2009	B2
7578751	Williams et al.	Aug 2009	B2
7578753	Beach et al.	Aug 2009	B2
D600767	Horacek et al.	Sep 2009	S
7582024	Shear	Sep 2009	B2
7591737	Gibbs et al.	Sep 2009	B2
7591738	Beach et al.	Sep 2009	B2
D604784	Horacek et al.	Nov 2009	S
7621823	Beach et al.	Nov 2009	B2
7628707	Beach et al.	Dec 2009	B2
7632194	Beach et al.	Dec 2009	B2
7632196	Reed	Dec 2009	B2
D608850	Oldknow	Jan 2010	S
D609294	Oldknow	Feb 2010	S
D609295	Oldknow	Feb 2010	S
D609296	Oldknow	Feb 2010	S
D609763	Oldknow	Feb 2010	S
D609764	Oldknow	Feb 2010	S
D611555	Oldknow	Mar 2010	S
D612004	Oldknow	Mar 2010	S
D612005	Oldknow	Mar 2010	S
D612440	Oldknow	Mar 2010	S
7674187	Cackett et al.	Mar 2010	B2
7674189	Beach et al.	Mar 2010	B2
7682264	Hsu et al.	Mar 2010	B2
7717807	Evans et al.	May 2010	B2
D616952	Oldknow	Jun 2010	S
7731603	Beach et al.	Jun 2010	B2
7744484	Chao	Jun 2010	B1
7749096	Gibbs et al.	Jul 2010	B2
7749097	Foster et al.	Jul 2010	B2
7753806	Beach et al.	Jul 2010	B2
7771291	Willett et al.	Aug 2010	B1
7789773	Rae et al.	Sep 2010	B2
7815520	Frame et al.	Oct 2010	B2
7857711	Shear	Dec 2010	B2
7857713	Yokota	Dec 2010	B2
D631119	Albertsen et al.	Jan 2011	S
7867105	Moon	Jan 2011	B2
7887434	Beach et al.	Feb 2011	B2
7927229	Jertson et al.	Apr 2011	B2
7946931	Oyama	May 2011	B2
7988565	Abe	Aug 2011	B2
8012038	Beach et al.	Sep 2011	B1
8012039	Greaney et al.	Sep 2011	B2
8083609	Burnett	Dec 2011	B2
8088021	Albertsen	Jan 2012	B2
8096897	Beach et al.	Jan 2012	B2
8118689	Beach et al.	Feb 2012	B2
8157672	Greaney et al.	Apr 2012	B2
8162775	Tavares et al.	Apr 2012	B2
8167737	Oyama	May 2012	B2
8187119	Rae et al.	May 2012	B2
8206241	Boyd et al.	Jun 2012	B2
8206244	Honea et al.	Jun 2012	B2
8216087	Breier et al.	Jul 2012	B2
8235841	Stites et al.	Aug 2012	B2
8235844	Albertsen et al.	Aug 2012	B2
8241143	Albertsen	Aug 2012	B2
8241144	Albertsen et al.	Aug 2012	B2
8292756	Greaney et al.	Oct 2012	B2
8328659	Shear	Dec 2012	B2
8353786	Beach et al.	Jan 2013	B2
8403771	Rice et al.	Mar 2013	B1
8430763	Beach et al.	Apr 2013	B2
8435134	Tang	May 2013	B2
8496544	Curtis et al.	Jul 2013	B2
8517860	Albertsen et al.	Aug 2013	B2
8529368	Rice	Sep 2013	B2
8591351	Albertsen et al.	Nov 2013	B2
8616999	Greaney et al.	Dec 2013	B2
8641555	Stites et al.	Feb 2014	B2
8663029	Beach et al.	Mar 2014	B2
8696491	Myers	Apr 2014	B1
8721471	Albertsen et al.	May 2014	B2
8753222	Beach et al.	Jun 2014	B2
8821312	Burnett	Sep 2014	B2
8858360	Rice et al.	Oct 2014	B2
8900069	Beach et al.	Dec 2014	B2
9089749	Burnett	Jul 2015	B2
9174101	Burnett	Nov 2015	B2
20010049310	Cheng et al.	Dec 2001	A1
20020022535	Takeda	Feb 2002	A1
20020025861	Ezawa	Feb 2002	A1
20020032075	Vatsvog	Mar 2002	A1
20020055396	Nishimoto et al.	May 2002	A1
20020072434	Yabu	Jun 2002	A1
20020115501	Chen	Aug 2002	A1
20020123394	Tsurumaki	Sep 2002	A1
20020137576	Dammen	Sep 2002	A1
20020160854	Beach et al.	Oct 2002	A1
20020183130	Pacinella	Dec 2002	A1
20020183134	Allen et al.	Dec 2002	A1
20030013545	Vincent et al.	Jan 2003	A1
20030032500	Nakahara et al.	Feb 2003	A1
20030036442	Chao et al.	Feb 2003	A1
20030130059	Billings	Jul 2003	A1
20030176238	Galloway et al.	Sep 2003	A1
20030220154	Anelli	Nov 2003	A1
20040087388	Beach	May 2004	A1
20040121852	Tsurumaki	Jun 2004	A1
20040157678	Kohno	Aug 2004	A1
20040176180	Yamaguchi et al.	Sep 2004	A1
20040176183	Tsurumaki	Sep 2004	A1
20040192463	Tsurumaki et al.	Sep 2004	A1
20040235584	Chao	Nov 2004	A1
20040242343	Chao	Dec 2004	A1
20050003905	Kim et al.	Jan 2005	A1
20050026716	Wahl et al.	Feb 2005	A1
20050049081	Boone	Mar 2005	A1
20050101404	Long	May 2005	A1
20050119070	Kumamoto	Jun 2005	A1
20050137024	Stites	Jun 2005	A1
20050181884	Beach et al.	Aug 2005	A1
20050239575	Chao et al.	Oct 2005	A1
20050239576	Stites et al.	Oct 2005	A1
20060009305	Lindsay	Jan 2006	A1
20060035722	Beach et al.	Feb 2006	A1
20060052177	Nakahara et al.	Mar 2006	A1
20060058112	Haralason et al.	Mar 2006	A1
20060073910	Imamoto et al.	Apr 2006	A1
20060084525	Imamoto et al.	Apr 2006	A1
20060094535	Cameron	May 2006	A1
20060116218	Burnett et al.	Jun 2006	A1
20060122004	Chen et al.	Jun 2006	A1
20060154747	Beach	Jul 2006	A1
20060172821	Evans	Aug 2006	A1
20060240908	Adams et al.	Oct 2006	A1
20060281581	Yamamoto	Dec 2006	A1
20070026961	Hou	Feb 2007	A1
20070049416	Shear	Mar 2007	A1
20070049417	Shear	Mar 2007	A1
20070082751	Lo et al.	Apr 2007	A1
20070105646	Beach et al.	May 2007	A1
20070105647	Beach et al.	May 2007	A1
20070105648	Beach et al.	May 2007	A1
20070105649	Beach et al.	May 2007	A1
20070105650	Beach et al.	May 2007	A1
20070105651	Beach et al.	May 2007	A1
20070105652	Beach et al.	May 2007	A1
20070105653	Beach et al.	May 2007	A1
20070105654	Beach et al.	May 2007	A1
20070105655	Beach et al.	May 2007	A1
20070117648	Yokota	May 2007	A1
20070117652	Beach et al.	May 2007	A1
20070275792	Horacek et al.	Nov 2007	A1
20080146370	Beach et al.	Jun 2008	A1
20080161127	Yamamoto	Jul 2008	A1
20080254911	Beach et al.	Oct 2008	A1
20080261717	Hoffman et al.	Oct 2008	A1
20080280698	Hoffman et al.	Nov 2008	A1
20090088269	Beach et al.	Apr 2009	A1
20090088271	Beach et al.	Apr 2009	A1
20090137338	Kajita	May 2009	A1
20090170632	Beach et al.	Jul 2009	A1
20090181789	Reed et al.	Jul 2009	A1
20090286622	Yokota	Nov 2009	A1
20100029404	Shear	Feb 2010	A1
20100048316	Honea et al.	Feb 2010	A1
20100048321	Beach et al.	Feb 2010	A1
20100113176	Boyd et al.	May 2010	A1
20100178997	Gibbs et al.	Jul 2010	A1
20110021284	Stites et al.	Jan 2011	A1
20110151989	Golden et al.	Jun 2011	A1
20110151997	Shear	Jun 2011	A1
20110218053	Tang et al.	Sep 2011	A1
20110244979	Snyder	Oct 2011	A1
20110281663	Stites et al.	Nov 2011	A1
20110281664	Boyd et al.	Nov 2011	A1
20110294599	Albertsen et al.	Dec 2011	A1
20120034997	Swartz	Feb 2012	A1
20120083362	Albertsen et al.	Apr 2012	A1
20120083363	Albertsen et al.	Apr 2012	A1
20120135821	Boyd et al.	May 2012	A1
20120142447	Boyd et al.	Jun 2012	A1
20120142452	Burnett et al.	Jun 2012	A1
20120178548	Tavares et al.	Jul 2012	A1
20120196701	Stites et al.	Aug 2012	A1
20120196703	Sander	Aug 2012	A1
20120244960	Tang et al.	Sep 2012	A1
20120270676	Berger et al.	Oct 2012	A1
20120277029	Albertsen et al.	Nov 2012	A1
20120277030	Albertsen et al.	Nov 2012	A1
20120289361	Beach et al.	Nov 2012	A1
20130184100	Burnett et al.	Jul 2013	A1
20140148270	Oldknow	May 2014	A1
20150105177	Beach et al.	Apr 2015	A1
20150231453	Harbert et al.	Aug 2015	A1

Foreign Referenced Citations (105)

Number	Date	Country
2436182	Jun 2001	CN
201353407	Dec 2009	CN
9012884	Sep 1990	DE
0470488	Feb 1992	EP
0617987	Nov 1997	EP
1001175	May 2000	EP
194823	Dec 1921	GB
57-157374	Oct 1982	JP
01091876	Apr 1989	JP
03049777	Mar 1991	JP
03151988	Jun 1991	JP
04180778	Jun 1992	JP
4180778	Jun 1992	JP
05337220	Dec 1993	JP
H05317465	Dec 1993	JP
H06126004	May 1994	JP
06182004	Jul 1994	JP
06190088	Jul 1994	JP
06190088	Jul 1994	JP
H06238022	Aug 1994	JP
06285186	Oct 1994	JP
H06304271	Nov 1994	JP
08117365	May 1996	JP
H09028844	Feb 1997	JP
H09308717	Dec 1997	JP
H09327534	Dec 1997	JP
10155943	Jun 1998	JP
H10234902	Sep 1998	JP
10263118	Oct 1998	JP
H10277187	Oct 1998	JP
H11114102	Apr 1999	JP
11-155982	Jun 1999	JP
2000167089	Jun 2000	JP
2000288131	Oct 2000	JP
2000300701	Oct 2000	JP
2000342721	Dec 2000	JP
2000014841	Jan 2001	JP
2001054595	Feb 2001	JP
2001129130	May 2001	JP
2001170225	Jun 2001	JP
2001204856	Jul 2001	JP
2001231888	Aug 2001	JP
2001346918	Dec 2001	JP
2004351054	Dec 2001	JP
2002003969	Jan 2002	JP
2002017910	Jan 2002	JP
2002052099	Feb 2002	JP
2002052099	Feb 2002	JP
2002136625	May 2002	JP
2002248183	Sep 2002	JP
2002248183	Sep 2002	JP
2002253706	Sep 2002	JP
2003024481	Jan 2003	JP
2003038691	Feb 2003	JP
2003052866	Feb 2003	JP
2003093554	Apr 2003	JP
2003093554	Apr 2003	JP
2003126311	May 2003	JP
2003210621	Jul 2003	JP
2003210627	Jul 2003	JP
2003226952	Aug 2003	JP
2003524487	Aug 2003	JP
2004008409	Jan 2004	JP
2004174224	Jun 2004	JP
2004174224	Jun 2004	JP
2004183058	Jul 2004	JP
2004222911	Aug 2004	JP
2004232397	Aug 2004	JP
2004261451	Sep 2004	JP
2004265992	Sep 2004	JP
2004267438	Sep 2004	JP
2004271516	Sep 2004	JP
2004275700	Oct 2004	JP
2004313762	Nov 2004	JP
2004313762	Nov 2004	JP
2004-351054	Dec 2004	JP
2004351054	Dec 2004	JP
2004351173	Dec 2004	JP
2004351173	Dec 2004	JP
2005028170	Feb 2005	JP
2005073736	Mar 2005	JP
2005111172	Apr 2005	JP
2005137494	Jun 2005	JP
2005137788	Jun 2005	JP
2005193069	Jul 2005	JP
2005193069	Jul 2005	JP
2005296458	Oct 2005	JP
2005296582	Oct 2005	JP
2005323978	Nov 2005	JP
2006320493	Nov 2006	JP
2007136069	Jun 2007	JP
2007136069	Jun 2007	JP
2007275253	Oct 2007	JP
4128970	Jul 2008	JP
2009000281	Jan 2009	JP
2010029590	Feb 2010	JP
2010279847	Dec 2010	JP
2011024999	Feb 2011	JP
WO8802642	Apr 1988	WO
WO0166199	Sep 2001	WO
WO02062501	Aug 2002	WO
WO03061773	Jul 2003	WO
WO2004043549	May 2004	WO
WO2005009543	Feb 2005	WO
WO2006044631	Apr 2006	WO

Non-Patent Literature Citations (27)

Entry
“Cleveland HiBore Driver Review,” http//thesandtrip.com, 7 pages, May 19, 2006.
“Invalidity Search Report for Japanese Registered Patent No. 4128970,” 4 pp (Nov. 29, 2013).
Office action from the U.S. Patent and Trademark Office in U.S. Appl. No. 13/401,690, dated Feb. 6, 2013.
Office action from the U.S. Patent and Trademark Office in U.S. Appl. No. 13/469,023, dated Jul. 31, 2012.
Office action from the U.S. Patent and Trademark Office in U.S. Appl. No. 13/338,197, dated Jun. 5, 2014.
Office action from the U.S. Patent and Trademark Office in U.S. Appl. No. 13/828,675, dated Jun. 30, 2014.
Restriction Requirement from the U.S. Patent and Trademark Office in U.S. Appl. No. 13/469,031, dated Jun. 5, 2014.
Office action from the U.S. Patent and Trademark office in the U.S. Appl. No. 13/401,690, dated May 23, 2012.
Adams Golf Speedline F11 Ti 14.5 degree fairway wood (www.bombsquadgolf.com, posted Oct. 18, 2010).
Callaway Golf, World's Straightest Driver: FT-i Driver downloaded from www.callawaygolf.com/ft%2Di/driver.aspx?lang=en on Apr. 5, 2007.
Jackson,Jeff, The Modern Guide to Golf Clubmaking, Ohio: Dynacraft Golf Products, Inc., copyright 1994, p. 237.
Nike Golf, Sasquatch 460, downloaded from www.nike.com/nikegolf/index.htm on Apr. 5, 2007.
Nike Golf, Sasquatch Sumo Squared Driver, downloaded from www.nike.com/nikegolf/index.htm on Apr. 5, 2007.
Office action from the U.S. Patent and Trademark office in the U.S. Appl. No. 12/781,727, dated Aug. 5, 2010.
Taylor Made Golf Company, Inc. Press Release, Burner Fairway Wood, www.tmag.com/media/pressreleases/2007/011807—burner—fairway—rescue.html, Jan. 26, 2007.
Taylor Made Golf Company Inc., R7 460 Drivers, downloaded from www.taylormadegolf.com/product—detail.asp?pID=14section=overview on Apr. 5, 2007.
Titleist 907D1, downloaded from www.tees2greens.com/forum/Uploads/Images/7ade3521-192b-4611-870b-395d.jpg on Feb. 1, 2007.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2004, pp. 82-86.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2005, pp. 120-130.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2005, pp. 131-143.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2006, pp. 122-132.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2006, pp. 133-143.
Mike Stachura, “The Hot List”, Golf Digest Magazine, Feb. 2007, pp. 130-151.
“The Hot List”, Golf Digest Magazine, Feb. 2008, pp. 114-139.
Mike Stachura, Stina Sternberg, “Editor's Choices and Gold Medal Drivers”, Golf Digest Magazine, Feb. 2010, pp. 95-109.
The Hot List, Golf Digest Magazine, Feb. 2009, pp. 101-127.
International Searching Authority (USPTO), International Search Report and Written Opinion for International Application No. PCT/US2011/038150, mailed Sep. 16, 2011, 13 pages.

Related Publications (1)

	Number	Date	Country
	20150231455 A1	Aug 2015	US

Continuations (2)

	Number	Date	Country
Parent	14472415	Aug 2014	US
Child	14701962		US
Parent	13397122	Feb 2012	US
Child	14472415		US

Continuation in Parts (1)

	Number	Date	Country
Parent	12791025	Jun 2010	US
Child	13397122		US

Iron-type golf club head having a sole stress reducing feature

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

Field of Search

US

International Classifications

Disclaimer

Term Extension

Abstract