Golf club head with grooves   

The present application claims priority to U.S. Provisional Patent Application No. 61/260,666, filed on Nov. 12, 2009, which is hereby incorporated by reference in its entirety.

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a golf club head. More specifically, the present invention relates to a golf club head having a plurality of grooves.

2. Description of the Related Art

The prior art discloses various methods to manufacture golf club heads, especially iron-type golf club heads. For example, Rogers, U.S. Pat. No. 4,027,885 for Golf Iron Manufacture, discloses scoring grooves into a face for the club head.

Taylor, U.S. Pat. No. 4,077,632 for a Lined Face For A Golf Club discloses grooves in compliance with the Rules of Golf at that time.

Ribaudo, U.S. Pat. No. 4,529,203, for Golf Club discloses a golf club face having grooves to eliminate the slice or the hook of the golf ball.

Shira, U.S. Pat. No. 4,768,787, for a Golf Club Including High Friction Striking Face discloses grit blasting the horizontal grooves to provide a friction generating surface when the striking surface of the golf club head engages a ball. The metallic matrix of the golf ball striking face contains hard particles which are harder than the metallic matrix and protrude above the surface.

Stuff, U.S. Pat. No. 5,354,059, for Golf Club Heads With Means For Imparting Corrective Action, discloses a club head with at least two non-parallel sets of grooves.

Doolen, U.S. Pat. No. 6,179,725, for a Golf Club Having Angular Grooves discloses grooves oriented at various angles. The plurality of grooves across the golf club face are angled at an angle that is substantially non-parallel with the club sole. All grooves however are sloped in the same direction as one another.

Hirota, U.S. Pat. No. 6,193,615, for a Head Of Golf Clubs That Spins More, discloses a face having grooves that allow for pressure to act specially on the edges of the grooves to increase ball spin.

Vokey et al, U.S. Pat. No. 7,473,187, for Spin Milled Grooves For A Golf Club, discloses machining grooves into a face.

Hettinger et al., U.S. Pat. No. 7,452,283, for a Putterhead With Dual Milled Face Pattern, discloses milling grooves into a face of a putter.

Kennedy, III, U.S. Pat. No. 7,179,175, for a Golf Club Having Stepped Grooves, discloses a golf club head with V-shaped and U-shaped grooves.

U.S Patent Application Publication Number 2009/0264217 to Johnson et al., for Golf Club Head Having a Grooved Face, discloses a spin milling or fly cutting method for forming grooves. This manner allows for tighter draft angles, increases the rate of production, and allows for tighter tolerances than casting or forging.

U.S. Patent Application Publication Number 2009/0247318 to Ban et al., for Golf Club Head, discloses a plurality of striations formed on the face and extending from a toe side to a heel side, where the cross sectional shape of each striation is a triangle asymmetric with regard to the a virtual center line in a width direction and the smallest interior angle of the three interior angles of the triangle being placed at the sole side of the golf club head.

Although these inventions have provided novel methods for forming grooves on the face of the golf club head, the prior art has not optimized groove formation.

Scoreline designs generally have a cross-section geometry that includes two edges, two side walls and a bottom. The side walls are at a predetermined angle from a vertical line. Usually, each wall has more than one section and those sections are straight or curved. Alternatively, the scoreline design is a “V” shape, in which case there is no bottom other than a vertex or fillet radius.

Iron-type golf clubs having scorelines with sharp edges and relatively vertical side walls are advantageous to golfers since such sharp edged grooves allow golfers to induce higher levels of spin on a ball struck with such an iron-type golf club having sharp edged grooves. Iron-type golf clubs without sharp edged grooves or essentially vertical side walls will induce less spin when impacting a golf ball, especially higher-lofted (40 degrees+) golf clubs.

The following requirements apply to apply to the collective set of grooves on any individual club head. Groove width (W) is measured per the USGA 30° method. Less than 50% of groove widths shall be greater than 0.035 inch and no single groove width shall be greater than 0.037 inch. Groove widths shall not vary by more than 0.010 inch from narrowest to widest. Groove depth (D) is measured per the USGA method from adjoining land areas. Less than 50% of groove depths shall be greater than 0.020 inch and no single groove depths shall be greater than 0.022 inch. Groove depths shall not vary by more than 0.010 inch from shallowest to deepest. Groove spacing (S) is measured per the USGA 30° method. Less than 50% of groove spaces shall be less than 0.075 inch or be less than three times the width of the widest amount adjacent groove. No single groove space shall be less than 0.073 inch or be less than three times the width of the widest adjacent groove minus 0.008 inch.

For heads other than drivers and putters, the area/pitch “A/P” is measured per the USGA method from adjoining land areas. Less than 50% of A/P values shall be greater than 0.0030 inch and no single A/P value shall be greater than 0.0032 inch. For heads having loft equal or greater than 25°, the effective radius “ER” is measured per the USGA 0.0110 inch R circle method. Less than 50% of the grooves shall have more than 10° of effective radius greater than 0.0110 inch and no single groove shall have any amount of effective radius greater than 0.0113 inch.

Backspin is the primary mechanism by which a golfer can control a golf ball upon landing after being struck. Backspin is especially important for short shots where proximity to the hole is of greater consequence to the golfer. High lofted clubs (50 degrees to 75 degrees) have grooves designs which are meant to interact with the surface of a golf ball at impact and remove debris from the contacting surface in order to increase friction and thereby impart more spin on the ball. Unlike intermediate lofts whose spin can either be increased or decreased with increased friction, the high lofted club will almost always increase spin through increased friction. Traditionally groove designs have focused on increasing the groove area underneath the golf ball at impact.

SUMMARY

The present invention provides a novel solution to imparting backspin by using high lofted golf clubs. The present invention increases the number of sharp edges that contact a golf ball during impact in order to increase the backspin. The sharp edges slice through debris and “grab” a soft cover of a golf ball better than grooves that have fewer edges. This leads to higher effective coefficients of friction for the golf club which in turn leads to more backspin.

For high lofted clubs, the sliding between the golf ball and the face of the golf club occurs during the majority of time of the impact between the golf ball and the face. Due to this sliding time period of the impact time, the backspin of a golf ball is increased by increasing the effective coefficient of friction between the two surfaces, the golf ball and the face of the golf club.

The effective coefficient of friction between the two surfaces, the golf ball and the face of the golf club, is primarily a function of the number of edges that the golf ball contacts and the sharpness of the edges. The impact also results in a finite area of contact between the golf ball and the face of the golf club. The area of contact is generally circular in shape. Due to the finite area of contact, there is a design of grooves that will maximize the length of edges that contact the ball during impact. The present invention maximizes the number of grooves in contact with a golf ball during an impact.

One aspect of the present invention is an iron-type golf club head with a body having a face. On the face is a first and second plurality of grooves. Each of the first plurality of grooves has a depth of at least 0.010 inch and each of the first plurality of grooves is spaced at least 0.9 inch from any other of the first plurality of grooves. Each of the second plurality of grooves has a depth of less than 0.001 inch.

Another aspect of the present invention is an iron-type golf club head with a body having a face. A first plurality of grooves is located on the face. Each of the first plurality of grooves has a depth of at least 0.010 inch and each of the first plurality of grooves is spaced at least 0.07 inch from any other of the first plurality of grooves. Additionally, a second plurality of grooves is located on the face. Each of the second plurality of grooves has a depth of less than 0.001 inch and each of the second plurality of grooves is spaced no more than 0.002 inch from an adjacent second plurality of grooves.

Yet another aspect of the present invention is a body having a face and a first plurality of grooves located on the face. Each of the first plurality of grooves has a depth of at least 0.010 inch and each of the first plurality of grooves is spaced at least 0.07 inch from any other of the first plurality of grooves. A plurality of second set of grooves is also located on the face, each of the plurality of second set of grooves having five microgrooves with a depth of less than 0.001 inch and spaced no more than 0.002 inch from an adjacent microgroove. Each second set of grooves of the plurality of second set of grooves is positioned between each of the first plurality of grooves.

Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

FIG. 1 is a perspective view of an iron-type golf club head.

FIG. 2 is a front view of an iron-type golf club head.

FIG. 3 is a rear view of an iron-type golf club head.

FIG. 4 is a top plan view of an iron-type golf club head.

FIG. 5 is a bottom plan view of an iron-type golf club head.

FIG. 6 is a toe side view of an iron-type golf club head.

FIG. 7 is heel side view of an iron-type golf club head.

FIG. 8 is an isolated and enlarged cross-sectional view of a groove.

FIG. 9 is an isolated and enlarged cross-sectional view of grooves on a face of an iron-type golf club head.

FIG. 10 is an isolated and enlarged image showing the effective radius of a groove.

FIG. 11 is a cross sectional view of a both the first set of plurality of grooves and the second set of plurality of grooves.

FIG. 11A is a view of an alternative cross sectional shape for the second set of plurality of grooves.

FIG. 11B is a view of another alternative cross sectional shape for the second set of plurality of grooves.

DETAILED DESCRIPTION

As shown in FIG. 1-7, an iron-type golf club is generally designated 20. The golf club head 20 also has a top portion 46, a sole portion 48, a heel portion 50, a toe portion 52 and a rear surface 54. The top wall 46 extends rearward from the top end of the front surface 23. The golf club head 20 includes a body 21 having a face 22 with a surface 23 and a plurality of grooves 25. The body 21 is preferably composed of a material such as titanium materials, stainless steel, carpenter steel, 1020 steel, amorphous metals and the like. The material of the body 21 preferably has a density between 4 g/cm3 and 10 g/cm3. Such titanium materials include pure titanium and titanium alloys such as 6-4 titanium alloy, 6-22-22 titanium alloy, 4-2 titanium alloy, SP-700 titanium alloy (available from Nippon Steel of Tokyo, Japan), DAT 55G titanium alloy available from Diado Steel of Tokyo, Japan, Ti 10-2-3 Beta-C titanium alloy available from RTI International Metals of Ohio, and the like. The body 21 is preferably manufactured through casting. Alternatively, the body 21 is manufactured through forging, forming, machining, powdered metal forming, metal-injection-molding, electro-chemical milling, and the like.

As shown in FIG. 8, a groove 25 of the first set of plurality of grooves has a width, W1, preferably ranging from 0.024 inch to 0.030 inch. The width is defined as the distance across a groove 25 from an inflection point of one end to an inflection point of the opposing end. Also, as shown in FIG. 8, a groove of the first set of plurality of grooves has a depth (D1) of at least 0.010 inch. Further, as shown in FIG. 9, a distance between grooves 25 is the spacing (S1) and each of the first plurality of grooves is spaced at least 0.1 inch from any other of the first plurality of grooves and is preferably between 0.075 inch and 0.11 inch. The distance (P) from the center of the groove (25) in the first set of plurality of grooves to the adjacent groove of the first set of grooves preferably ranges from 0.102 inch to 0.142 inch.

As shown in FIGS. 9-10, each of the grooves 25 of the second set of plurality of grooves has a depth (D2) of less than 0.001 inch. A groove 25 of the second set of plurality of grooves has a width, W2, preferably ranging from 0.001 inch to 0.010 inch. Further, as shown in FIG. 9 the spacing (S2) between each of the second plurality of grooves is spaced no more than 0.002 inch from an adjacent second plurality of grooves.

Additionally, each of the second plurality of grooves may have a V-like cross-sectional shape as shown in FIG. 11, square cross-sectional shape as shown in FIG. 11A, or U-like cross-sectional shape as shown in FIG. 11B.

As shown in FIG. 10, the effective radius (“ER”) of a groove (25) is shown. The “ER” is preferably 0.010 inch.

As shown in FIG. 11, a groove (25) in the first set of plurality of grooves may have a base (“B”) which ranges from 0.005 inch to 0.009 inch.

The following is used to calculate the number of grooves (n) in the second set of plurality of grooves between the first set of plurality of grooves:

n = S   1 S   2

wherein 0.002 inch≦S2≦0.20 inch

Although a preferred embodiment of an iron-type golf club head is illustrated in the figures, other structures are used with the scorelines as disclosed herein.

Alternatively, the structure of the iron-type golf club is such as disclosed in Helmstetter, et al., U.S. Pat. No. 5,776,010, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Schmidt, et al., U.S. Pat. No. 5,749,795, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Schmidt, et al., U.S. Pat. No. 5,704,849, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Blough et al., U.S. Pat. No. 5,921,869, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Kosmatka, U.S. Pat. No. 5,971,868, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Kosmatka, U.S. Pat. No. 6,045,455, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Kosmatka, U.S. Pat. No. 6,186,905, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Erickson, et al., U.S. Pat. No. 6,210,290, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Reyes, et al., U.S. Pat. No. 7,144,336, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Deshmukh, U.S. Pat. No. 7,112,148, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Aguinaldo, et al., U.S. Pat. No. 7,083,531, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Wieland, et al., U.S. Pat. No. 7,338,389, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Nycum, et al., U.S. Pat. No. 7,338,387, which is hereby incorporated by reference in its entirety.

Alternatively, the structure of the iron-type golf club is such as disclosed in Holt, et al., U.S. Pat. No. 7,326,126, which is hereby incorporated by reference in its entirety.

From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims.