Patent Application
20140274451
This invention relates generally to golf clubs. In particular, the invention relates to golf clubs having grooves formed in a front face of a golf club head.
The popularity of the game of golf has increased immensely in recent decades. All manner of players are looking for equipment that will improve an individual's performance, thereby making the game more enjoyable. Golf's regulating bodies, such as the United States Golf Association (“USGA”), institute rules and limitations on the design, configuration, etc. of golf clubs, and thus clubs must be designed to remain within the regulations of the ruling body, while still providing expected or improved performance.
One such regulation deals with club head grooves and their shape, size, spacing, configuration, etc. The USGA has enacted regulations limiting the size, shape, and volume of golf club grooves, including for the groove limitations for clubs having a loft angle greater than 25°. Limiting groove sizes and edge angles is expected to limit the club's ability to channel away water, grass, and other debris during a ball strike and is expected to limit or reduce the spin induced on the ball by the ball strike. These features are expected to result in more inconsistent shots (particularly out of the rough). Accordingly, there is a need in the art for golf club heads having conforming grooves that have improved or more consistent performance.
The following presents a general summary of aspects of the invention in order to provide a basic understanding of the invention and various features of it. This summary is not intended to limit the scope of the invention in any way, but it simply provides a general overview and context for the more detailed description that follows.
Aspects of this invention relate to golf clubs and golf club heads having grooves formed in a ball striking surface of the front face of the golf club head wherein the grooves are formed with a wall angle of approximately 27 degrees from a reference axis extending perpendicular to the front face of the golf club head such that the distance between the sidewalls decrease from the top of the groove to the bottom of the groove. The reference axis may be considered an axis of symmetry centered in the groove.
The groove configurations of the present invention provide optimized collective dimensions allowing the grooves to better grip a golf ball upon impact and as a result, provide highly consistent spin properties and trajectory properties for all playing conditions, wherein, in at least some of the examples of this invention, the groove configurations are in conformance with the Rules of Golf as currently promulgated by the USGA.
A more complete understanding of the present invention and certain advantages thereof may be acquired by referring to the following detailed description in consideration with the accompanying drawings, in which:
The reader is advised that the attached drawings are not necessarily drawn to scale.
In the following description of various example structures in accordance with the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example articles, including one or more golf club or golf club head structures. Additionally, it is to be understood that other specific arrangements of parts and structures may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Also, while the terms “top,” “bottom,” “front,” “back,” “rear,” “side,” “underside,” “overhead,” and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein as a matter of convenience, e.g., based on the example orientations shown in the figures and/or the orientations in typical use. Nothing in this specification should be construed as requiring a specific three dimensional or spatial orientation of structures relative to external structures in order to fall within the scope of this invention. Further, the invention generally will be described as it relates to wedge-type golf clubs. However, aspects of the invention may be used with any of several types of golf clubs, including iron-type clubs, wood-type golf clubs, hybrid type golf clubs, and the like, and nothing in the specification or figures should be construed to limit the invention to use with the wedge-type golf clubs described.
In general, as described above, aspects of this invention relate to golf clubs or golf club head structures. More detailed descriptions of aspects of this invention follow.
Aspects of this invention relate to golf club and golf club head structures. In at least some examples, the golf club head may include a golf club head body having a toe, a heel, a top or crown, a sole, a rear and a front face, the front face including a ball striking surface. The golf club head may further include a plurality of grooves formed in the ball striking surface. In some arrangements, at least one groove of the plurality of grooves has a first sidewall and a second sidewall, each sidewall extending inward from the front ball striking face of the golf club head body to a bottom or interior end of the groove, wherein each side wall slopes inwardly toward the bottom of the groove at an angle of approximately 27 degrees from a reference axis perpendicular to the face of the club such that the distance between the sidewalls decreases from the top of the groove to the bottom of the groove.
Other example golf club head structures in accordance with this invention may include a plurality of grooves formed in the ball striking surface, wherein at least a first groove of the plurality of grooves has a first end arranged proximate the toe and a second end arranged proximate the heel, wherein the first groove has a first sidewall and a second sidewall, each sidewall extending inward from the front ball striking face of the golf club head body to a bottom or interior end of the groove, wherein each side wall slopes inwardly toward the bottom of the groove at an angle of approximately 27 degrees from a reference axis perpendicular to the face of the club such that the distance between the sidewalls decreases from the top of the groove to the bottom of the groove.
Still other aspects of this invention relate to golf clubs including a golf club shaft and a golf club head connected to one end of the shaft, wherein the golf club head is any of the various types described above. While aspects of this invention may be practiced on any type of golf club head (e.g., drivers, fairway woods, hybrids, and putters), in some examples, aspects of this invention will be practiced with wedge type and iron type golf clubs and golf club heads. Also, aspects of this invention may be practiced on clubs generally known as or corresponding to 5-irons to 9-irons, pitching wedges, sand wedges, gap wedges, lob wedges, and the like.
As some more specific examples, golf clubs and golf club heads in accordance with at least some examples of this invention will have a loft angle of 25° or more, and in some examples, within a range of 25° to 68°, or even within a range of 25° to 64°. Some more specific examples of this invention will include golf clubs and golf club heads having loft angles within the range of range of 45° to 64°.
The groove design of the present invention allows for improved ball spin in “mist” conditions creating similar ball spin as in a dry condition (e.g. the ball loses less spin in mist conditions as compared with other groove structures.)
In at least some aspects, methods of forming golf clubs and/or golf club heads may include forming a golf club head body including a toe, a heel, a top or crown, a sole, a rear and a front face, the front face including a ball striking surface (e.g. by a casting, forging, molding, or other process.) The methods further include forming a plurality of grooves in the ball striking surface of the golf club head body. In certain embodiments, the grooves may be formed in a stamping operation or in a cutting or grinding operation. Other suitable manufacturing operations can also be used including a metal injection molding process. The methods may further include connecting the golf club head to a shaft.
Additional aspects and specific examples of the articles described above will be described in detail more fully below. The reader should understand that these specific examples are set forth merely to illustrate examples of the invention, and they should not be construed as limiting the invention.
Referring to the figures and following discussion, example golf clubs and golf club heads in accordance with the present invention are described. As discussed above, the golf club and club head structures described herein may be described in terms of iron-type golf club, including wedge-type clubs. However, the present invention is not limited to the precise arrangements disclosed herein but applies to golf clubs generally, including wood-type clubs, hybrid clubs, and the like.
Golf club heads may generally include a plurality of different regions, segments, portions, ends, etc. In an example embodiment, a golf club head may generally include a front ball striking face, a rear, a toe, a heel, a top or crown and a sole. The golf club heads may include a single or a multiple piece construction and structure, e.g., including one or more individual parts corresponding to a sole, a front face (optionally including a ball striking surface that may be integrally formed therein or attached thereto), a top or crown, a bottom or sole, a rear, etc. If desired, various portions of the club head structure may be integrally formed with one another, as a unitary, one piece construction, without departing from the invention (e.g., the front face and/or rear may be integrally formed with the sole and/or top, etc.). Optionally, if desired, the various portions of the club head structure (such as the sole, the top, the face member, the rear, etc.) individually may be formed from multiple pieces of material without departing from this invention (e.g., a multi-piece top, a multi-piece sole, etc.). Also, as other alternatives, if desired, the entire club head may be made as a single, one piece, unitary construction, or a front face may be attached to a one piece club head rear (optionally, a hollow body, etc.). More specific examples and features of golf club heads and golf club structures according to this invention will be described in detail below in conjunction with the example golf club structures illustrated in the Figures.
The shaft 106 may be received in, engaged with, and/or attached to the club head 102 in any suitable or desired manner, including in conventional manners known and used in the art, without departing from the invention. As more specific examples, the shaft 106 may be engaged with the club head 102 via a hosel 104 and/or directly to the club head structure 102, e.g., via adhesives, cements, welding, soldering, mechanical connectors (such as threads, retaining elements, or the like), etc.; through a shaft-receiving sleeve or element extending into the club head body 102; etc. The shaft 106 also may be made from any suitable or desired materials, including conventional materials known and used in the art, such as graphite based materials, composite or other non-metal materials, steel materials (including stainless steel), aluminum materials, other metal alloy materials, polymeric materials, combinations of various materials, and the like. Also, the grip or handle 108 may be attached to, engaged with, and/or extend from the shaft 106 in any suitable or desired manner, including in conventional manners known and used in the art, e.g., using adhesives or cements; via welding, soldering, or the like; via mechanical connectors (such as threads, retaining elements, etc.); etc. As another example, if desired, the grip or handle 108 may be integrally formed as a unitary, one-piece construction with the shaft 106. Additionally, any desired grip or handle 108 materials may be used without departing from this invention, including, for example: rubber materials, leather materials, rubber or other materials including cord or other fabric material embedded therein, polymeric materials, and the like.
The club head 102 itself also may be constructed in any suitable or desired manner and/or from any suitable or desired materials without departing from this invention, including from conventional materials and/or in conventional manners known and used in the art. For example, in the example club head 102 shown in
A wide variety of overall club head constructions are possible without departing from this invention. For example, if desired, some or all of the various individual parts of the club head 102 described above may be made from multiple pieces that are connected together (e.g., by welding, soldering, or other fusing techniques; by mechanical connectors; by adhesives or cements etc.). The various parts (e.g., crown, sole, front face, rear, etc.) may be made from any desired materials and combinations of different materials, including materials that are conventionally known and used in the art, such as metal materials, including lightweight metal materials, and the like. More specific examples of suitable lightweight metal materials include steel, titanium and titanium alloys, aluminum and aluminum alloys, magnesium and magnesium alloys, nickel and nickel alloys, etc. Additionally or alternatively, the various parts of the club head may be formed of one or more composite materials. The club head 102 also may be made by forging, casting, or other desired processes, including club head forming processes as are conventionally known and used in the art.
The various individual parts that make up a club head structure 102, if made from multiple pieces, may be engaged with one another and/or held together in any suitable or desired manner, including in conventional manners known and used in the art. For example, the various parts of the club head structure 102, such as the front face 101, ball striking surface 102a, the top 103, the sole 105, etc., may be joined and/or fixed together (directly or indirectly through intermediate members) by adhesives, cements, welding, soldering, or other bonding or finishing techniques; by mechanical connectors (such as threads, screws, nuts, bolts, or other connectors); and the like. If desired, the mating edges of various parts of the club head structure 102 may include one or more raised ribs, tabs, ledges, or other engagement elements that fit into or onto corresponding grooves, slots, surfaces, ledges, openings, or other structures provided in or on the facing side edge to which it is joined. Cements, adhesives, mechanical connectors, finishing material, or the like may be used in combination with the raised rib/groove/ledge/edge or other connecting structures described above to further help secure the various parts of the club head structure 102 together.
The dimensions and/or other characteristics of a golf club head structure according to examples of this invention may vary significantly without departing from the invention, and the dimensions may be consistent with those commonly used in the art for similar club heads and clubs.
The golf club head 102 of
As shown in
Golf club heads may be manufactured to have dimensions consistent with Appendix II of The Rules of Golf (2010-2011) as promulgated by the USGA (“the Rules”) hereby incorporated by reference in its entirety. Grooves are within the purview of the Rules and club heads of the present invention must include grooves that fall within the parameters of the groove rules in order to produce a club head that complies with USGA Rules. For example, for clubs other than driving clubs, the cross-sectional area (A) of a groove divided by the groove pitch (W+S) must not exceed 0.0030 square inches per inch (0.0762 mm2/mm).
A/(W+S)≦0.0030 in2/in.
W is the width of each groove and S is the distance between edges of adjacent grooves. Golf club heads in accordance with at least some examples of the present invention will conform to this Rule and yet provide an unexpected superior performance.
The grooves 250 have a cross-section with a bottom portion or surface 256 being narrower than the groove width W at the top or open side. The groove width W at the top is defined as the distance between the tangent points T of a single groove 250. For instance, the grooves 250 may have a generally trapezoidal cross-section with a top portion being open such that sidewalls 254 and 258 of the grooves 250 may taper toward each other as they extend from the front face 240 of the golf club head inward, toward a rear of the golf club head. That is, a bottom portion of opposing sidewalls 254, 258 may be closer together than a top portion of the sidewalls 254, 258. The grooves 250 also may be separated from one another by a distance “S” as shown in
As some additional examples, as shown by
In this illustrated example, the groove 420 has a generally rectangular appearance or outer perimeter from the front, as shown in
The clubs according to the invention may have surface roughness between the grooves, e.g., applied by laser, sand blasting, water jet blasting, milling, grinding, etc. This type of surface Roughness must comply with the Rules, Appendix II, 5b (ii).
Similar to
In the specific, non-limiting, example shown in
In other aspects of the invention, dimensions disclosed herein may be provided with certain tolerances and ranges while still falling within the scope of the present invention. For example, each sidewall has a 25.5 to 28.5 degree angle from a reference line or axis of symmetry AS (a reference axis normal to the face plane shown in
In accordance with at least some examples of this invention, the grooves 650 may have a depth “d” of 0.013 to 0.018 inches (0.33 to 0.46 mm) (and in some examples, from 0.015 to 0.017 inches (from 0.38 to 0.43 mm) and even from 0.015 to 0.016 inches (from 0.38 to 0.41 mm)) The depth is a depth taken from the top of the groove to the bottom of the groove.
In accordance with at least some examples of this invention, the grooves 650 may have a width “W” at the top of the groove is from 0.025 to 0.030 inches (from 0.64 to 0.76 mm) (and in some examples, from 0.027 to 0.028 inches (from 0.68 to 0.72 mm)). The width W2 at the bottom of the groove may be determined by the width W, the depth d, and the side wall angle.
In accordance with at least some examples of this invention, the grooves 650 may also be separated from one another (distance “S” in
In accordance with at least some examples of this invention, the groove area may be (A) is 0.00028 to 0.00036 in2. In accordance with at least some examples of this invention, the area (A) of each of said grooves divided by groove pitch (S+W) is 0.0018 to 0.0030 in2/in or 0.0023 to 0.0030 in2/in.
As shown in
Further, as exemplified in
The number of grooves on a wedge-type golf club head may depend, for instance, on loft angle. For example, a greater loft angle may provide a larger surface area; hence, more grooves may be desired. The determination of the number of the grooves is within the skill of the art and based on the type of club head, size of club head, and the like. With the groove structures described herein, an idealized number of grooves can be positioned within a set linear distance on the ball's striking face.
When a golf ball is struck by a golf club head, the side of the ball in contact with the face flattens as the ball cover and core compress. This flattening puts more area of the ball surface into contact with the club face (the ball/face contact area is represented in
Thus
As discussed above, the present invention may be applicable to any suitable golf club head face. Aspects of the invention are particularly directed to a wedge-type golf club head. Wedge golf club heads having grooves in accordance with the present invention have performance consistent with other wedges having grooves but provides unexpected superior performance under mist or wet conditions, e.g. playing in morning dew, playing in wet conditions, etc.
The grooves may be made in the face of the golf club head by any suitable method such as machining, stamping, grinding, milling, cutting and the like. Such methods are within the skill of the art. One issue recognized with stamping is the stamped groove can create a swell. Hence, if a stamped groove is desired, a double stamping technique may be used to eliminate the swell.
Notwithstanding the claims, the invention is also defined by way of the following clauses:
a groove width extending across the top of the groove of 0.025 to 0.030 inch;
wherein spacing (S) between adjacent grooves is 0.085 to 0.095 inches; and
Five different iron-type club heads with different groove structures were tested under mist and dry conditions. The clubs had the following characteristics:
In a first test, club head performance was compared with respect to spin rates measured from hits using a robot such that the hits had a consistent speed, head path, and angle for a target distance (ball flight distance) of about 30 yards. Such tests were performed under dry and mist conditions.
Mist tests were conducted with a Fluidotech piston pump; 10-20 gpm, water reservoir (1-2 gallons); 30° mist nozzle; and 6-10 feet nylon tubing. The following protocol was followed: 1) Setup the swing robot for club and launch parameters. 2) Prime pump and test mist pattern. 3) Position mist nozzle above ball so the mist cone wets the back of the ball and covers the club head path 4 to 6 inches prior to ball impact; adjust mist nozzle if needed. 4) Wet club face with water using damp towel or nylon brush prior to first hit. 5) Place ball on robot tee, start mist pump and hit one shot to evenly wet and distribute water on club face. Allow club to return through impact area and turn off pump. Discard the shot. 6) Start the shot series within 30 seconds; place ball on tee, start mist pump, and hit shots. Continue to run the mist pump through the test sequence. 7) Repeat steps 4 and 5 when time between sequential shots and/or test setup exceeds 30 seconds.
The table below provides comparisons of the results including % spin lost or gained in mist conditions over dry conditions.
Inventive Sample #2 performed the best followed by Inventive Sample #1. Notably, the wet conditions did not result in as much spin loss for the wedges in accordance with this invention as compared to the comparative wedges. Thus, the wedges according to these examples of the invention performed more consistently under the wet and dry conditions.
In a second test, spin rates were measured from hits using a robot such that the hits had a consistent speed, head path, and angle for a target distance of about 60 yards. The table below provides comparisons of the results including % spin lost or gained in mist conditions over dry conditions.
Again, Inventive Sample #2 performed the best followed by Inventive Sample #1.
Thus it was discovered that the grooves in accordance with this invention provided excellent spin results, and particularly, less loss of spin under mist (wet) conditions. Dispersion results were also improved. This allows the golfer to be more consistent in his/her game (e.g., the golfer can feel more confident that the club will perform similarly under different conditions of play).
In a third test, club head performance was compared with respect to ball speed for a 30 yard test shot and the results are presented in the following table:
In a fourth test, club heads performance was compared with respect to ball speed for a 60 yard test shot, and the results are presented in the following table:
This data demonstrates that the ball speed does not substantially suffer (or is not substantially degraded) for the Inventive Sample grooves under wet conditions. While the inventive grooves show improved maintenance of spin rate under wet conditions, the inventive grooves also showed similar, if not somewhat improved ball speed performance as compared to the other grooves from a ball speed loss point of view (i.e., the inventive grooves lost less ball speed or substantially the same ball speed (wet v. dry) when compared to the other grooves). Thus, again, one using the club would see little change in ball speed performance (wet v. dry), and thus one would expect the ball to fly similar distances (wet v. dry).
In a fifth test, club head performance was compared with respect to launch angle for a 30 yard test shot, and the results are presented in the following table:
In a sixth test, club heads performance was compared with respect to launch angle for a 60 yard test shot, and the results are presented in the following table:
This data shows that the launch angle does not change as much for the Inventive Grooves (wet v. dry) as the other grooves. Again, this would make the club head having grooves according to the present invention perform more consistently under different play conditions (wet v. dry) than the clubs with the other grooves.
In a seventh test, club head performance was compared with respect to maximum height during flight for a 30 yard test shot, and the results are presented in the following table:
In an eighth test, club head performance was compared with respect to maximum height during flight for a 60 yard test shot, and the results are presented in the following table:
This data demonstrates that the ball's maximum launch height does not change as much for the Inventive grooves under different conditions of play (wet v. dry) as compared to the other grooves. One using the clubs with the Inventive grooves would see little change in maximum ball launch height under different play conditions (wet v. dry), and thus one would expect the ball to fly more similar distances under these different conditions (wet v. dry).
In a ninth test, club head performance was compared with respect to total carry distance for a 30 yard test shot, and the results are presented in the following table:
In a tenth test, club head performance was compared with respect to total carry distance for a 60 yard test shot, and the results are presented in the following table:
This data demonstrates that the ball carry distance does not substantially change (or is not substantially degraded) for the Inventive grooves under wet conditions. While the inventive grooves show improved maintenance of spin rate under wet conditions, the inventive grooves also showed similar, if not somewhat improved, wet. dry ball carry distance performance as compared to the other grooves (i.e., in wet conditions, the inventive grooves performed close to the same as the dry grooves, and the inventive grooves performed substantially the same, if not somewhat better than the other grooves). Thus, again, one using the club of the invention would see little change in ball carry performance (wet v. dry), and thus one would expect the ball to fly similar distances (wet v. dry).
In an eleventh test, club head performance was compared with respect to side-carry for a 30 yard test shot, and the results are presented in the following table:
In a twelfth test, club heads performance was compared with respect to side-carry for a 60 yard test shot, and the results are presented in the following table:
This data demonstrates that the Inventive grooves perform comparable to the other grooves from a side carry point of view (“side carry” refers to the amount the ball drifts off the initial center flight line, e.g., due to inducement of side spin on the ball). The wet v. dry data for the inventive grooves is similar to (or even somewhat improved for Inventive Sample 2) the wet v. dry performance data for the other clubs.
In view of the above data, a player using a club with the Inventive grooves could perform more consistently under wet or dry conditions (i.e., the stroke can be played substantially the same in wet or dry conditions and the ball could be expected to react similarly, wet v. dry). This gives the player less variables and more confidence when making the stroke. The data shows the Inventive grooves to be better at maintaining wet to dry performance then the Comparative grooves for spin performance (i.e., less reduction in spin wet v. dry), launch angle performance (i.e., less change in launch angle wet v. dry), and maximum ball height performance (i.e., closer to the same maximum height wet v. dry). The data also show that the Inventive grooves perform substantially the same as (and in some instances, somewhat improved to) the Comparative grooves for ball speed performance (i.e., reduction in spin wet v. dry), carry distance performance (i.e., change in carry distance wet v. dry), and side carry performance (i.e., stays closer to the launch direction wet v. dry).
While aspects of this invention have been described for use in conjunction with conforming grooves (conforming to the 2010-2011 USGA groove regulations), this is not a requirement. Rather, if desired, aspects of this invention may be applied to golf club heads with any desired types of conforming or non-conforming grooves.
While the invention has been described in detail in terms of specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and methods. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims.
