JP2011125723A - Golf club with improved performance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a golf club head that is capable of achieving an improved sweet spot, defined as a portion of a striking face that has at least 99.7% of the maximum ball speed. <P>SOLUTION: The golf club head 100 has the significantly circular shaped sweet spot which surrounds at least about 1.5% of a total striking face 102. The golf club head 100 includes: an improved face geometry whose elliptical factor is, generally, greater than about 0.5; a beveled transition portion 112 around the striking face 102 of the golf club head 100; a variable thickness area which decreases thickness; or a tilt bulge and roll radius. These are all useful to improve performance of the golf club head 100. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention generally relates to a golf club head capable of realizing an improved sweet spot, defined as a portion of a striking face, wherein the ball speed is at least 99.7% of the maximum ball speed. More specifically, the present invention relates to a golf club head in which a sweet spot covers at least 1.5% of the overall golf club striking face. More specifically, the present invention provides a significantly elliptical shape that achieves an improved sweet spot with an elliptical factor greater than about 0.50 when the elliptical factor is defined as the minor axis divided by the major axis. The present invention relates to a golf club head having the upper striking face. The present invention may also relate to a golf club head that further improves the performance of the golf club head with an inclined bulge and roll diameter.

  In the competitive industry of golf club design, distance and accuracy are two of the most important performance factors that help meet the demands of metal wood type golf clubs. Some argue that the appearance, feel, and sound of a golf club may affect the evaluation of the golf club, but claim that performance factors play a major role in determining the demands of a golf club There is no. Performance factors that maintain accuracy while maximizing distance are becoming even more important in metal wood type golf club heads. Unlike iron-type golf club heads, where golf shot accuracy clearly prioritizes the benefits of distance achieved by any individual golf club, metal-wood type golf club heads are as far as possible and as straight as possible to the golfer. Designed to hit golf balls.

  In order to maximize the distance of the metal wood type golf club head and still maintain accuracy, the metal wood type golf club head is hit by the golf club head near the geometric center of the golf club head. It has been designed with the goal of maximizing distance. This geometric center of the golf club head can generally achieve a golf shot that maximizes distance by reducing energy loss between the golf ball and the golf club head in accordance with inherent physical laws. In order to quantify this value, the United States Golf Association (USGA) has worked with the golf industry as a way to quantify the rebound characteristics of a golf ball after it has collided with a golf club head. Various methods of calculation and feature time (CT) calculation have been provided.

  US Pat. No. 6,390,933 (Galloway, “'933 patent”, first patent document) has a coefficient of restitution greater than 0.845 and is 2000 times with a golf ball of 110 miles per hour. Disclosed is a golf club head that is durable to withstand impacts and is exploring one approach to increasing the COR of a golf club head, where the club head is comprised of three parts: a face, a sole, and a crown. good. More specifically, the '933 patent may be composed of a titanium material, with a volume ranging from 175 cubic cm to 400 cubic cm, a weight ranging from 165 grams to 300 grams, and a striking plate area. A golf club head that is in the range of 4.00 square inches to 7.50 square inches is disclosed.

  US Patent Application Publication No. 2004/0116202 (Lin, “'202 Patent Application Publication”, 2nd Patent Document), which pursues accuracy in place of distance, includes a plurality of holes around the club head. By disclosing a golf club head in which most vibration waves and acoustic waves are dissipated from these holes when the club head strikes the golf ball so as to improve the accuracy of the direction of the striking golf ball. We are investigating ways to improve the accuracy of the head.

  However, when well tested, developments that maximize the distance while maintaining the accuracy of a metalwood golf club head are based on the premise that a golfer can hit a golf ball at a sweet spot. The sweet spot generally matches the geometric center of the golf club and is such a small area of the golf club head's striking face, making it difficult for the average golfer to consistently hit the golf ball at the sweet spot. I will. Thus, in addition to the performance factors described above, the size of the sweet spot is increased to design the distance and accuracy of the golf club head without requiring the average golfer to hit the golf ball perfectly every time. It would also be desirable to be able to take advantage of the above advantages.

  To address the challenge that golfers are not always able to hit golf balls at the center of the hitting face, the industry has attempted to experiment with different variable face thickness hitting faces. In fact, various golf club heads may even have multiple zones of varying thickness, improving the size of the sweet spot, even when the average golfer does not hit the golf ball at the center of the hitting face. It is designed to achieve the best results. Despite the fact that these approaches can improve the size of the club head, they do not take into account the performance benefits realized by adjusting the actual geometry of the golf club head's striking face.

  From the above, it can be seen that there is a need in the art for golf club heads that can utilize the golf club head striking face geometry itself to increase the size of the sweet spot of the golf club head. More specifically, it enables an average golfer to achieve similar performance benefits that an experienced professional golfer can achieve, even when not directly hitting a golf ball at the center of the golf club head. There is a need in this field for golf club heads.

US Pat. No. 6,390,933 US Patent Application Publication No. 2004/0116202

One aspect of the invention is a golf club head having a striking face, a rear body portion, and a beveled transition portion. The striking face may comprise a front surface area greater than about 3500 mm ² . The rear body portion may further include a crown portion coupled to the upper portion of the striking face and a sole portion coupled to the lower portion of the striking face. The beveled transition portion at least partially surrounds the perimeter of the striking face and couples the striking face to the rear body portion. The striking face may be accompanied by a sweet spot, defined as the area of the front surface area, with at least 99.7% of the maximum ball speed achievable with the golf club head, which is about the front surface area of the striking face. Includes more than 1.5%.

Another aspect of the invention is a golf club head having a striking face, a rear body portion, and a beveled transition portion. The striking face may comprise a front surface area greater than about 3500 mm ² . The rear body portion may further include a crown portion coupled to the upper portion of the striking face and a sole portion coupled to the lower portion of the striking face. The beveled transition portion at least partially surrounds the perimeter of the striking face and connects the striking face to the rear body portion, the beveled transition portion is the beveled transition of the toe and the heel Transition portion. The toe beveled transition portion has a radius of curvature greater than about 30 mm and the heel beveled transition portion has a radius of curvature greater than about 25 mm.

Yet another aspect of the present invention is a golf club head having a striking face and a rear body portion. The striking face may comprise a front surface area greater than about 3500 mm ² . The rear body portion may further include a crown portion coupled to the upper portion of the striking face and a sole portion coupled to the lower portion of the striking face. The front surface area of the striking face further includes a bulge radius extending from the heel portion to the toe portion in a substantially horizontal direction across the front surface area of the striking face, and a crown portion in a substantially vertical direction across the front surface area of the striking face. Roll radius extending from the base to the sole portion, the bulge radius and the roll radius being inclined in the direction from high toe to low heel.

  These and other features, aspects, and advantages of the present invention will be understood with reference to the following drawings, description, and claims.

    The foregoing and other features and advantages of the invention will be apparent from the following description of the invention, illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and constitute a part of the specification, serve to explain the principles of the invention and enable those skilled in the art to practice the invention.

1 is an overhead view of a golf club head according to an exemplary embodiment of the present invention. 1 is a front view of a golf club head according to an exemplary embodiment of the present invention. 2 is a graphical representation of a typical collision pattern between a golf club and a golf ball. 1 is a front view of a golf club head illustrating the relative size, shape, and position of a sweet spot according to an exemplary embodiment of the present invention. FIG. It is a graph display of the enlarged view of the conventional sweet spot relevant to the conventional golf club head. 2 is a graphical representation of an enlarged view of an improved sweet spot according to an exemplary embodiment of the present invention. 1 is a plan view of a golf club head according to an exemplary embodiment of the present invention. FIG. 8 is a cross-sectional view of the golf club head according to the exemplary embodiment of the present invention, taken along the line A-A ′ of FIG. 7. 1 is a front view of a golf club head according to an exemplary embodiment of the present invention, showing the back geometry of the striking face. FIG. 2 is a graphical representation of an enlarged view of an improved sweet spot according to an exemplary embodiment of the present invention. 1 is a perspective view from the toe of a golf club head according to an exemplary embodiment of the present invention. FIG. 1 is a perspective view from the heel of a golf club head according to an exemplary embodiment of the present invention. FIG. 2 is a graphical representation of an enlarged view of an improved sweet spot according to an exemplary embodiment of the present invention. 1 is a front view of a golf club head showing an inclined bulge and roll diameter according to an exemplary embodiment of the present invention. FIG.

  The following detailed description is of the best current project model for practicing this invention. This description should not be taken in a limiting sense, but is made only for the purpose of illustrating the general principles of the invention. This is because the scope of the invention is best defined by the appended claims.

  Various inventive features are described below, each of which may be employed independently of other features or may be used in combination with other features. However, any one feature of the invention may not address any or all of the above-mentioned problems, or may handle only one of the above-mentioned problems. Further, one or more of the problems described above may not be addressed with any of the features described below.

  FIG. 1 shows an overhead view of a golf club head 100 in accordance with an exemplary embodiment of the present invention. The golf club head 100 shown in FIG. 1 may generally include a striking face 102, a rear body portion 104, and a hosel 105. The rear body portion 104 may generally further comprise a crown portion 106, a sole portion (not shown), and a skirt portion 110. The crown portion 106 is generally coupled to the upper portion of the striking face 102, while the sole portion (not shown) may be generally coupled to the lower portion of the striking face 102. The skirt portion 110 may be generally disposed between the crown portion 106 and the sole portion (not shown) to complete the posterior body portion 104, as shown in current example embodiments. The golf club head 100 may generally include a beveled transition portion 116, as shown in the current example embodiment illustrated by FIG. At least besiege. More specifically, as can be seen from FIG. 1, the slope transition portion 112 may further comprise a toe slope transition portion 114 and a heel slope transition portion 116, which are near the toe and heel portions of the striking face 102, respectively. The hitting face 102 is surrounded. Although the current example embodiment shown in FIG. 1 shows only a slope transition portion 112 that covers the toe and heel portions of the golf club head 100, the slope transition portion 112 does not depart from the scope and content of the present invention. Note that the perimeter of the striking face 102 may be completely enclosed.

1, a surface area of the striking face 102 is generally greater than about 3600 mm ^2, more preferably greater than 3700 mm ^2, and most preferably it should be noted that may be greater than about 3750mm ^2. Furthermore, the surface area of the inclined transition portion 112 is generally less than about 850 mm ^2, more preferably less than 825 mm ^2, and most preferably may be less than about 810 mm ^2. Finally, the overall surface area of the golf club head 100 is between about 32000 mm ² and about 35000 mm ² . In relation to the surface area values described above, it is important to determine the ratio of the surface area of the striking face 102 to the overall total area of the golf club head 100. The striking face surface area ratio is generally greater than about 9%, more preferably greater than about 10%, and most preferably greater than about 11%. Alternatively, the surface area described above also determines the slope transition partial surface area ratio. This slope transition portion surface area is generally less than about 3.0%, more preferably less than about 2.75%, and most preferably less than about 2.5%.

FIG. 2 shows a front view of a golf club head 200 in accordance with an exemplary embodiment of the present invention. The front view of this golf club head 200 can show the striking face 202 more directly, with the striking face 202 being significantly elliptical, the long axis 220 running significantly from the heel to the toe, Shows that the shaft runs significantly from the crown to the sole. The striking face 202 of the golf club head 200 according to an exemplary embodiment of the present invention generally has an ellipticity factor of greater than about 0.33, more preferably greater than about 0.41, and most preferably about 0.50. It can be accompanied. The elliptic factor discussed above may be defined by Equation 1 below.
Elliptic factor = length of minor axis 222 / length of major axis 220 Formula (1)
The major axis length 220 may be generally defined as the distance of the longest line that can be drawn on the striking face 202. In the current example embodiment shown here in FIG. 2, the major axis 220 extends significantly in the heel-to-toe direction, but the major axis 220 is oriented in any other direction that deviates from the current orientation. May be. However, it represents the longest line that can be drawn on the striking face 202 without departing from the scope and content of the present invention. The minor axis 222 may be generally defined as a line that runs perpendicular to the major axis 220 and traverses the striking face 202 as shown in the current example embodiment, but the geometric center of the striking face 202 Go through 201.

  The length of major axis 220 may generally be less than about 120 mm, more preferably less than about 110 mm, and most preferably less than about 100 mm, as shown in current example embodiments. On the other hand, the length of the minor axis 222 may generally be greater than about 40 mm, more preferably greater than about 45 mm, and most preferably greater than about 50 mm, as shown in current example embodiments. . Therefore, when the length of the minor axis 222 is divided by the length of the major axis 220, the resulting elliptic factor may be in the range previously discussed.

  The front view of the golf club head 200 shown in FIG. 2 shows how much the striking face 202 of the golf club head 200 is tilted to a more upright position even when the golf club head 200 is maintained in a relatively flat position. Help to show. In other words, the vertical minor axis 222 of the striking face 202 may generally be inclined by an angle θ when compared to the vertical axis 223 perpendicular to the ground 225. The angle θ is generally greater than about 3.0 degrees and less than about 16.0 degrees, and more preferably greater than about 3.0 degrees and about 12 degrees, as shown in current example embodiments. It may be less than 0.0 degrees, and most preferably greater than about 3.0 degrees and less than about 8.0 degrees. As can be seen from FIG. 2, the inclination of the hitting face 202 of the golf club head 200 relative to the ground 225 causes the major axis 220 and the minor axis 222 to be tilted in the same direction by the same degree. Viewed another way, the slope of the striking face 202 is greater than about 3.0 degrees and less than about 16.0 degrees from the high toe to the low heel direction of the major axis 220 and minor axis 222, more preferably It can also be defined as tilting by an angle greater than about 3.0 degrees and less than about 12.0 degrees, and most preferably greater than about 3.0 degrees and less than about 8.0 degrees.

  It is useful to look at FIG. 3 to understand the reason behind the slope of the striking face 202 of the golf club head 200, which shows a golfer's typical impact pattern against the striking face 202, and the points on the graph Indicates a typical hitting position when a golfer hits a golf ball with a golf club. F. Werner and R.W. Greg, How Golf Clubs Really Working and How to Optimize The Designs, Ch. 4, pp. 17-21 (2000), the typical dispersion of golf ball hits on the face of a driver club follows an elliptical pattern with the major axis oriented from high toe to low heel. Matches the elliptical pattern shown in FIG. When examining the collision pattern shown in FIG. 3 closer, it can be seen that the major axis 320 of the impact pattern forms an angle α with respect to the horizontal axis 323. This angle α may generally coincide with the inclination angle θ of the hitting face 202 of the golf club head 200 shown in FIG. More specifically, α is generally greater than about 3.0 degrees and less than about 16.0 degrees, more preferably greater than about 3.0 degrees and less than about 12.0 degrees, most preferably It is larger than about 3.0 degrees and smaller than about 8.0 degrees.

  Returning to FIG. 2, it can be seen from the striking pattern shown in FIG. 3 that the striking face of the golf club head 200 is preferably tilted by an angle θ corresponding to the tilt angle α of the impact pattern. More importantly, tilting the striking face 202 of the golf club head 200 will tilt the major axis 220 and the minor axis 222. This is because the hitting face 202 can be made to more closely match the typical hitting pattern shown in FIG. 3 by inclining the above-mentioned axis.

  Referring to FIG. 4, this shows another front view of a golf club head according to an embodiment of the present invention where the golf club head 400 is located near the geometric center 401 of the striking face 402 of the golf club head 400. It can be seen that the sweet spot 430 is shown. More specifically, the sweet spot 430 is generally concentric with the geometric center 401 of the striking face 402 of the golf club head 400. One of the main advantages of a golf club head 400 designed in accordance with the present invention is that it can provide an improved sweet spot that is significantly larger than previously achieved. More specifically, the golf club head 400 according to an exemplary embodiment of the present invention preferably has a portion greater than about 1.5% of the total surface area of the striking face 402, more preferably the total of the striking face 402. A sweet spot 430 may be provided that surrounds a portion greater than about 1.75% of the surface area, most preferably greater than about 2.0% of the total surface area of the striking face 402. In the context of this application, the sweet spot 430 is generally defined as the area of all striking faces 402 that can achieve at least 99.7% of the maximum ball speed achievable by the golf club head 400. good. A value of 99.7% would be reasonable to use in determining the size of the sweet spot 430. This is because a golf ball that can achieve 99.7% of the maximum ball speed is about 1/2 when compared to a direct center hit that achieves 100% of the maximum ball speed that can be achieved with the golf club head 400. Only mile, par, and time are lost. The maximum ball speed that can be achieved with the golf club head 400 as shown in the current example embodiment is generally achieved with the golf club head, regardless of where the golf club head 400 strikes the golf ball. Associated with the highest ball speed possible.

Here, in FIG. 4, the area of the striking face 402 of the golf club head 400 according to an exemplary embodiment of the present invention is generally greater than about 3600 mm ² , more preferably greater than 3700 mm ² , most preferably It may be greater than about 3750 mm ² . On the other hand, the area of the sweet spot 430, generally greater than about 75 mm ^2, more preferably greater than 110 mm ^2, and most preferably be greater than about 120 mm ^2. A better view of the sweet spot 430 showing an improved geometric profile will be shown later in FIGS. Here, this can focus on an enlarged ball velocity grid showing an enlarged view of the sweet spot 430. Considering the striking face 402 and the sweet spot 430 above, the sweet spot 430 represents a portion of the striking face 402 that is greater than about 1.5%, more preferably a portion of the striking face 402 that is greater than about 1.75%. Most preferably, it surrounds a portion of the striking face 402 that is greater than about 2.0%.

In order to adequately describe the size of the sweet spot 430 according to an exemplary embodiment of the present invention, it would be beneficial to examine whether the hitting face portion of a conventional golf club head is generally a sweet spot. FIG. 5 shows a conventional golf club head sweet spot 530 having at least 99.7% of the maximum ball speed within a ball speed grid 531 positioned on the hitting face of the conventional golf club head. The ball velocity grid 531 may be a rectangular area generally 40 mm wide and 20 mm high positioned on the striking face of a golf club head, as defined in this context. A typical conventional golf club head sweet spot 530 is typically about 45 mm ² in area and is significantly smaller than the sweet spot 430 that can be achieved with a golf club head 400 in accordance with an exemplary embodiment of the present invention.

  It is meaningful to understand that the prior art sweet spot 530 shown in FIG. 5 is significantly oval in addition to being significantly smaller in size. Here, the major axis 532 extends significantly in the horizontal direction, and the minor axis significantly extends in the vertical direction. Examining a conventional sweet spot 530 in a conventional golf club head closer, the long axis of the sweet spot is significantly longer than the short axis, here the horizontal end around the sweet spot along the long axis Is significantly away from the periphery of the sweet spot at the vertical edge. Such an elliptical sweet spot 530 would be undesirable. This is because it fails to grasp the tip of a typical impact pattern as shown in FIG. This is particularly noticeable when the mistake is at a high toe or low heel position.

FIG. 6 shows a sweet spot 630 of a golf club head according to an example embodiment of the present invention within a ball speed grid 631 of the same size. Initially and most importantly, as can be seen from FIG. 6, the size of the sweet spot 639 is significantly larger than the size of the conventional sweet spot 530 shown in FIG. More specifically, the area of the sweet spot 630 shown in the current example embodiment is typically about 75 mm ² , which is derived from the improved face shape previously shown in FIG. Let's go. In addition to the large sweet spot 630, the improved sweet spot 630 has an improved more circular shape so that the sweet spot 630 covers a greater portion of the impact area shown in FIG. More specifically, the sweet spot 630 may generally have a more circular shape, as shown in the current example embodiment of FIG. 6, with the major axis 632 and the minor axis 634 being approximately the same length. In other words, while maintaining the area of the sweet spot 630 at about 75 mm ² , none of the points around the sweet spot 630 will be further than about 5.0 mm from the geometric center of the sweet spot 630.

  Although the improved face geometry shown in FIG. 2 improves the size and shape of the sweet spot 630 shown in FIG. 6, further example embodiments of the golf club head shown in FIGS. Additional features and advantages are realized that would further improve the performance of the golf club head 200 shown in FIG. Reference is now made to FIG. 7, which shows a top view of a golf club head 700 according to another exemplary embodiment of the present invention, which comprises a variable thickness striking face 702. Although the variable thickness is not understandable from FIG. 7, FIG. 7 provides a cross-sectional line AA ′ through the center of the golf club head 700 so that the cross-sectional profile of the golf club head 700 is the variable thickness profile in FIG. Shown with.

  FIG. 8a shows a cross-section of the golf club head 700 along the cross-sectional line A-A 'shown in FIG. Golf club head 800 includes a striking face 802, with a variable face thickness profile 840 behind it, as shown in the current example embodiment of FIG. 8a. More specifically, the variable face thickness profile 840 generally comprises a thickness center portion 842, as shown in the current example embodiment, which is surrounded by a transition portion 843, which Is surrounded by a thin peripheral portion 844. The striking face 802 of the golf club head 800 deforms like a trampoline when colliding with a golf ball, and the variable face thickness profile 840 makes the peripheral portion 844 of the striking face 802 thin enough to achieve the trampoline effect. Nevertheless, the thick central portion 842 of the variable face thickness profile 840 provides sufficient thickness to withstand the stress associated with the golf ball. Because the slope transition portion 112 (shown in FIG. 1) can provide additional structural rigidity to the striking face 802 of the golf club head 800, the golf club head striking face 802 can be made thinner to achieve a larger sweet spot. More specifically, as the structural rigidity is increased, the thickness of the thin peripheral portion 844 can be less than about 3.0 mm, more preferably less than about 2.9 mm, and most preferably less than about 2.8 mm. A detailed description of using a variable face thickness to improve golf club head performance can be found in US Pat. No. 7,029,403 (Rice et al.). These details are incorporated herein by reference.

  FIG. 8 b shows a front view of the internal geometry of the golf club head 800 with a variable face thickness profile 840. More specifically, FIG. 8b shows the size and position of the central portion 842, the transition portion 843, and the thin peripheral portion 844. Although not specifically labeled in FIG. 8b, because the striking face 802 of the golf club head 800 is inclined from high heel to low toe, the variable face thickness profile 840 is high toe to low heel. It may be inclined in the direction by an angle θ. The angle θ is generally greater than about 3.0 degrees and less than about 16.0 degrees, more preferably greater than about 3.0 degrees and about 12.0 degrees, as discussed above in FIG. It may be smaller, most preferably greater than about 3.0 degrees and less than about 8.0 degrees.

  It can also be noted in FIG. 8b that the central portion 842 generally comprises an elliptical profile shape with a major axis 820 that runs substantially from heel to toe and a minor axis 822 that runs substantially from crown to sole. is important. The shape and protrusion of the central portion 842 is defined by the relative lengths of the major axis 820 and the minor axis 822 and may generally relate to the ellipticity factor discussed in FIG. The central portion 842 of the striking face 902 according to an exemplary embodiment of the present invention generally has an elliptic factor that is greater than about 0.33, more preferably greater than about 0.41, and most preferably greater than about 0.50. This can be accompanied by calculation based on the previous equation (1).

  An enlarged view of the variable face thickness profile 840 also shows an interesting relationship of the transition portion 843 to the various thickness central portions 842. More specifically, as can be seen from FIG. 8b, the transition portion 843 may be accompanied by a variable transition width C1, C2, C3, or C4 that varies depending on the measurement position. The transition widths C1, C2, C3, and C4 may take different values, so that the central portion 842 is displaced within the transition portion 843 without departing from the scope and content of the present invention. “Transition Width”, as employed herein, generally refers to the distances C1, C2, C3, and C4 and is measured from a point perpendicular to the tangent taken at a point across the center portion 842. The distance between the periphery of the central portion 842 and the periphery of the transition portion 843 is represented.

  In other words, the geometric center of the central portion 842 shown in FIG. 8b may be offset from the geometric center of the transition portion 843 in the two-dimensional plane shown in FIG. 8b. In one exemplary embodiment of the present invention, the transition width C1 near the top of the transition portion 843 may generally be greater than the transition width C2 near the bottom of the transition portion 843. More specifically, transition width C2 may be generally equal to about 80% of transition width C1 to improve the performance of variable face thickness profile 840. Such a ratio of the wide transition width C1 to the narrow transition width C2 can provide a central portion 842 located near the bottom or sole of the striking face 802, where the position is sole biased. In the present example embodiment of the invention, the transition width C1 may generally be greater than about 8.0 mm, while the width C2 may generally be less than about 7.0 mm. More specifically, the transition width C1 may generally be about 8.5 mm, while the transition width C2 may generally be about 6.8 mm. However, in other alternative embodiments of the invention, a central portion located near the top or crown of the striking face 802 having a transition width C2 greater than the transition width C1 without departing from the scope and content of the invention. 842 may be realized.

  Without changing the transition widths C1 and C2 of the transition portion 843 along the minor axis 822 and without departing from the scope and content of the present invention, the transition widths C3 and C4 along the major axis 820 are adjusted to adjust the transition portion 843. Note that the size and position of the central portion 842 may be varied internally. Indeed, the present invention may include adjusting transition widths C1, C2, C3, and C4 all at the same time without departing from the scope and content of the present invention. In one exemplary embodiment of the present invention, transition widths C3 and C4 are approximately the same width as transition width C1, and central portion 842 may be more centrally located within transition portion 843. In alternative embodiments of the invention, the transition width C3 or C4 may be greater than the transition width C1, thereby further increasing the size or position of the central portion 842 without departing from the scope and content of the invention. You may adjust. In other alternative embodiments of the invention, transition widths C3 and C4 are generally greater than about 8.0 mm, more preferably greater than about 8.2 mm, and most preferably greater than about 8.3 mm. .

FIG. 9 shows a sweet spot 930 according to another exemplary embodiment of the present invention, which employs both the improved face geometry shown in FIG. 2 and the variable face thickness profile shown in FIG. ing. As can be seen from FIG. 9 using the same size ball velocity grid 931 as previously shown, the sweet spot 930 is significantly larger than any of the previous plots. More specifically, the size of the sweet spot 930 corresponds to a golf club head 900 that incorporates a variable face thickness profile in addition to improved face geometry, typically having an area of about 110 mm ² . Accompany. In addition to the larger sweet spot 930, the sweet spot 930 may have a more circular shape so that the sweet spot 930 can surround a greater portion of the impact area shown in FIG. As already described in FIG. 6, the sweet spot 930 is generally more circular, and in this shape, the area of the sweet spot 930 is maintained around 110 mm ² while surrounding the sweet spot 930. None of these points is more than about 6.0 mm away from the geometric center of the sweet spot 930.

  FIGS. 10, 11 and 12 illustrate another alternative embodiment of the present invention wherein the slope transition portion at least partially surrounding the striking face increases the performance of the golf club by increasing the sweet spot. To improve. More specifically, since the slope transition portion at least partially surrounds the striking face, the slope transition portion provides additional structural rigidity, thereby making the striking face thinner. A thin striking face golf club head would be beneficial in terms of performance characteristics. This is because according to this, by adjusting the thickness of various positions, the weight available for forming a large sweet spot by being distributed around the hitting face of the golf club head can be increased. .

  In addition to the above points, the slope transition portion could also improve the golfer's confidence factor when the golfer hits the golf ball with the golf club head. Golfers are becoming golf clubs with specific shapes and geometries, so if the golf club's shape or geometry deviates from its traditional shape or size, the golfer will be distracted by the unusual shape and geometry, and will be confident. I will lose it. With the above-described elliptic factor that improves the performance of a golf club head, the golf club head's striking face deviates from its normal shape and size, so some people will consider a golf club head of such shape, size, and geometry as I think it is not idiomatic. The slope transition portion helps to address this challenge by removing useless material from the perimeter of the striking face and returns the golf club head to a more traditional shape. More specifically, the slope transition portion may have a larger radius of curvature around the toe and heel portions, reconstructing the traditional shape and geometry of the golf club head and breathing confidence in the golfer.

  FIG. 10 shows a perspective view of a golf club head 1000 of the present invention as viewed from the toe portion of the golf club head 1000 in accordance with an exemplary embodiment of the present invention. The perspective view with emphasis on the toe of the golf club head 1000 shows an inclined transition portion 1012 around the toe portion of the golf club head 1000. More specifically, FIG. 10 illustrates various radii of curvature around the striking face 1002 that are used to form the slope transition portion 1012. The radius of curvature of the crown transition portion 1015 of the golf club head 1000 may be generally less than about 5 mm, more preferably less than about 3 mm, and most preferably less than about 2 mm between the striking face 1002 and the crown 1006. . In contrast, the radius of curvature of the toe slope transition portion 1014 may generally be variable to achieve an appropriate transition between the crown transition portion 1015 and the sole transition portion 1017. More specifically, the radius of curvature for the toe slope transition portion 1014 is greater than about 25 mm at the flattest point, more preferably greater than about 30 mm at the flattest point, and most preferably at about the flattest point. It may be larger than 35 mm. Thus, as can be seen from FIG. 10, the crown transition portion 1015 generally has a constant radius of curvature, while the toe slope transition portion 1014 has a variable radius of curvature of about 2 mm to about 35 mm, and Smooth transitions between them may be ensured. Although the toe transition portion 1014 generally refers to the toe portion around the striking face 1002, it extends to the crown transition portion 1015 or to the sole transition portion 1017, which departs from the scope and content of the present invention. Note that it may be possible to smooth between variable radii of curvature.

  FIG. 11 shows a perspective view of a golf club head 1100 of the present invention as viewed from the heel portion of the golf club head 1100 in accordance with an exemplary embodiment of the present invention. Similar to FIG. 10, the golf club head 1100 has a crown transition portion with the same radius of curvature as previously discussed in FIGS. 10 and 11, but this is greater than about 20 mm at the flattest point, more preferably Shows a heel slope transition portion 1116 with a radius of curvature greater than about 25 mm at the flattest point and most preferably greater than about 27.5 mm at the flattest point. Similar to the toe slope transition portion 1014 (shown in FIG. 10), the heel slope transition portion 1116 may have a variable radius of curvature from about 2 mm to about 2.75 mm to ensure a smooth transition between the two transition portions. . The heel transition portion 1116 extends to the crown transition portion 1115 or also extends to the sole transition portion 1117 to allow smoothing between variable radii without departing from the scope and content of the present invention. good.

FIG. 12 shows a sweet spot 1230 according to another example embodiment of the present invention, which includes the improved face geometry shown in FIG. 2, the variable face thickness profile shown in FIG. 8, and FIGS. 11 is employed. As can be seen from FIG. 12 using the same size ball velocity grid 1231 as previously shown, the sweet spot 1231 is significantly larger than any of the previous plots. More specifically, the size of the sweet spot 1230 is generally associated with an area of about 120 mm ² , corresponding to a golf club head 1200 incorporating all of the features described above. In addition to the larger sweet spot 1230, the sweet spot 1230 may also be more circular, in which shape any area around the sweet spot 1230 while maintaining the area of the sweet spot 1230 at about 120 mm ² . The point is not further than about 7.0 mm from the geometric center of the sweet spot 1230.

  FIG. 13 illustrates another alternative embodiment of the present invention in which the striking face 1302 includes a tilted bulge radius 1350 as well as a tilted roll radius to help improve the performance of the golf club head. You can do it. The bulge radius 1350 may refer to the curvature of the striking face 1302 extending substantially horizontally across the striking face 1302 from the heel portion to the toe portion. On the other hand, the roll radius 1352 may generally refer to the curvature of the striking face 1302 extending generally vertically across the striking face 1302 from the crown portion to the sole portion. Inclined Bulge Radius 1350 and Inclined Roll Radius 1352 will not further increase the size of the golf club head sweet spot, but will help correct missed shots by imparting a corrective spin to the golf ball. Will. A detailed discussion can be found in US Pat. No. 6,595,869 (McCabe et al.) Regarding the effect of a striking face 1302 with a bulge radius 1350 and a roll radius 1252, the contents of which are incorporated herein by reference.

  It is important to note that in the current example embodiment shown in FIG. 13, the striking face 1302 of the golf club head 1300 is tilted more upright by an angle θ, as already shown in FIG. is there. As described above, the angle θ makes it possible to match many portions of the hitting face 1302 with the normal golfer's collision pattern shown in FIG. However, without any adjustment to the bulge radius 1350 and roll radius 1352, bulge and roll compensation will no longer fit correctly in that the golf ball is spun to the center position. Accordingly, it may be preferred that the bulge radius 1350 and the roll radius 1352 be tilted upright by an angle Φ. The angle Φ is greater than about 1 degree and less than about 16 degrees, more preferably greater than about 1 degree and less than about 12 degrees, and most preferably greater than about 1 degree and less than about 8 degrees. In other words, the bulge radius 1350 and roll radius 1352 are from greater than about 1 degree to less than about 16 degrees, more preferably greater than about 1 degree and less than about 12 degrees, most preferably about 1 in the high toe to low heel direction. It may be tilted by an angle greater than about 8 degrees and less than about 8 degrees. Although the current tilt angle Φ may generally match the tilt angle θ of the golf club head 1300, the tilt angles Φ of the bulge radius 1350 and the roll radius 1352 do not depart from the scope and content of the present invention, respectively. Note that it can be determined independently of the inclination angle θ of the golf club head 1300.

  Outside the examples, or unless otherwise stated, all numerical ranges, quantities, values and percentages such as amount of material in the specification, moment of inertia, center of gravity, loft, drposter, various Such performance ratios, etc., can be recognized as having the term “about”, even if the term “about” is not clearly indicated with the value, amount, or range. Accordingly, unless indicated to the contrary, the numerical parameters in the specification and claims are approximations, which vary depending upon the desired properties desired to be realized by the present invention. Although not intended to exclude the application of the equivalence theory of the claims, at least the parameters of each quantity should be understood under the reported number of execution digits and understood by the usual rounding method.

  Although the quantity ranges and parameters representing the broad scope of this invention are approximate, the quantity values shown in the examples of the specification are reported as accurately as possible. However, any quantity value has inherent errors due to the standard deviations found in the measurements of each experiment. Further, where ranges of quantities are indicated for various things, it should be understood that combinations of the above indicated value ranges can be used.

  It should be noted that the foregoing relates to exemplary embodiments of the present invention and modifications can be made without departing from the scope and extent of the invention as set forth in the following claims.

100 golf club head 102 hitting face 104 rear body portion 105 hosel 106 crown portion 110 skirt portion 112 inclined transition portion

Claims (14)

A striking face having a front surface area greater than about 3500 mm ² ;
A rear body portion having a crown portion and a sole portion, wherein the crown portion is coupled to an upper portion of the striking face, and the sole portion is coupled to a lower portion of the striking face;
A beveled transition portion that at least partially surrounds the perimeter of the striking face and couples the striking face to the back body portion;
The striking face is a sweet spot defined as an area of the front surface area with at least 99.7% of the maximum ball speed that can be achieved by the golf club head, and is about 1 of the front surface area of the striking face. A golf club head having the sweet spot including a portion exceeding 5%.   The golf club head according to claim 1, wherein the sweet spot is concentric with a geometric center of the hitting face. The golf club head of claim 1, wherein the sweet spot area is greater than about 75.00 mm ² . The hitting face has an elliptical shape with an ellipticity factor greater than about 0.50,
4. A golf club head according to claim 3, wherein the elliptic factor is defined as a minor axis of the hitting face divided by a major axis of the hitting face.   The golf club head according to claim 4, wherein the major axis and the minor axis are inclined in a direction from a high toe to a low heel. A striking face having a front surface area greater than about 3500 mm ² ;
A rear body portion having a crown portion and a sole portion;
The crown portion is coupled to the upper portion of the striking face, the sole portion is coupled to the lower portion of the striking face, and
The front surface area of the hitting face is further
A bulge radius extending from the heel portion to the toe portion in a substantially horizontal direction across the front surface area of the striking face;
Roll radius extending from the crown portion to the sole portion in a substantially vertical direction across the front surface area of the striking face;
The bulge radius is inclined from high toe to low heel, and
The above-mentioned roll radius is a golf club head inclined from a high toe to a low heel.   The golf club head of claim 6, wherein the bulge radius and the roll radius have an inclination angle of between about 1 degree and about 16 degrees.   The golf club head of claim 6, wherein the bulge radius and the roll radius have an inclination angle between about 1 degree and about 8 degrees.   The golf club head further includes a beveled transition portion that at least partially surrounds the perimeter of the striking face and couples the striking face to the back body portion. The golf club head of claim 7, comprising at most 3.0% of the total surface area. The golf club head of claim 9, wherein the beveled transition portion is less than about 850 mm ² . A striking face having a front surface area greater than about 3500 mm ² ;
A rear body portion having a crown portion and a sole portion, wherein the crown portion is coupled to an upper portion of the striking face, and the sole portion is coupled to a lower portion of the striking face;
A beveled transition portion that at least partially surrounds the perimeter of the striking face and couples the striking face to the rear body portion;
The hitting face has an elliptical shape with an ellipticity factor greater than about 0.50,
The elliptical factor is a golf club head defined as a minor axis of the striking face divided by a major axis of the striking face.   The golf club head according to claim 11, wherein the major axis and the minor axis are inclined in a direction from a high toe to a low heel.   The golf club head of claim 12, wherein the major axis and the minor axis have an inclination greater than about 3 degrees and less than about 16 degrees. The striking face has a variable thickness, and the variable thickness is further
A thick central part,
A transition part,
With a thin surrounding portion,
The transition portion surrounds the thick central portion,
The thin surrounding portion surrounds the transition portion;
The golf club head of claim 11, wherein the thick central portion is disposed in the transition portion biased toward the sole of the golf club head.

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