Golf club head

The present invention relates to a golf club head having a hollow structure.

Currently, large heads with a golf club head volume exceeding 430 cc are being developed. As the head becomes larger, the sweet area of the head expands, making it possible to create a gentle golf club with little reduction in flight distance even on off-core shots. However, when the size of the head having a hollow structure is increased, the thickness of the members constituting the crown portion and the sole portion becomes thinner in order to maintain the weight reduction of the head, so that the hitting sound when hitting the ball is low. It tends to be.

In general, a high hitting sound peculiar to a metal head is preferred, so a device has been made to raise the hitting sound of such a large and lightweight head. For example, in Japanese Patent Application Laid-Open No. 2003-339922, in order to obtain a high-pitched and clear hitting sound, a small metal plate is provided on the inner surface of the golf club head on the toe side of the sole portion, and one of the plate surfaces is the sole portion. It is described that the metal is fixed in close contact with the metal. Further, in Japanese Patent Application Laid-Open No. 2006-204604, when at least one rib extending from the toe side to the heel side is arranged on the sole portion in order to improve a low hitting sound, the toe side end of the rib is arranged. It is stated that the heel side edge is bent and extended so that it is closer to the face side than the center area of the rib.

On the other hand, not all golfers like the high-pitched metallic hitting sound. In JP-A-2008-200319 and JP-A-2008-200339, in order to make the hitting sound of the golf club head louder and reverberate longer, the sole portion is more than the minimum radius of curvature of the face surface of the golf club head. The radius of curvature of the crown or side portion is increased, and ribs or flat plate members are provided in the portion where the radius of curvature is increased, and the value of the resonance frequency of this portion is within ± 10% of the value of the resonance frequency of the face surface. It is stated that it should be.<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2003-339922</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2006-204604</text></patcit><patcit num="3"><text>Japanese Unexamined Patent Publication No. 2008-200319</text></patcit><patcit num="4"><text>Japanese Unexamined Patent Publication No. 2008-200339</text></patcit>

<p> The present invention is unique even if the volume of a golf club head having a hollow structure is increased to 430 to 500 cc and the weight is reduced to 160 to 220 g in order to respond to the variety of golfer's preference for hitting sound. An object of the present invention is to provide a golf club head that emits a low hitting sound.</p>

<p> In order to achieve the above object, the golf club head according to the present invention is provided with a face portion, a sole portion, a crown portion and a side portion as one aspect thereof, has a hollow structure, and has a head volume of 430 to 500 cc. In a golf club head that is within the range and the head weight is within the range of 160 to 220 g, the area of the sole portion is set to a range such that the primary natural frequency of the sole portion is 2400 Hz or less. To do.</p><p> As another aspect, the golf club head according to the present invention includes a face portion, a sole portion, a crown portion and a side portion, has a hollow structure, has a head volume in the range of 430 to 500 cc, and has a head weight of 160. A golf club head having a weight in the range of ~ 220 g is characterized in that a weight is formed on the inner surface of the sole portion so that the primary natural frequency of the sole portion is 2400 Hz or less.</p><p> As yet another aspect, the golf club head according to the present invention includes a face portion, a sole portion, a crown portion and a side portion, has a hollow structure, has a head volume in the range of 430 to 500 cc, and has a head weight of 430 to 500 cc. In a golf club head in the range of 160 to 220 g, the radius of curvature of the outer surface of the sole portion in the toe-heel direction should be 230 mm or more so that the primary natural frequency of the sole portion is 2400 Hz or less. It is a feature.</p><p> In the second and third aspects described above, the area of the sole portion is 3000 to 14000 mm.²It is preferable to keep it within the range of. Further, in the first and third aspects, it is preferable to form a weight on the inner surface of the sole portion at the anti-vibration portion of the sole portion. Further, in the first and second aspects described above, it is preferable that the radius of curvature of the outer surface of the sole portion in the toe-heel direction is 230 mm or more.</p>

<p> As described above, according to the present invention, even in a large and lightweight golf club head having a head volume of 430 to 500 cc and a head weight of 160 to 220 g, the area of the sole portion can be increased or the sole portion can be increased. By attaching a weight to the inner surface on the hollow structure side of the sole, or by setting the radius of curvature of the outer surface of the sole in the toe-heel direction to 230 mm or more, the primary natural frequency of the sole can be set to 2400 Hz or less. Therefore, a unique low hitting sound can be obtained.</p>

Hereinafter, embodiments of the golf club head according to the present invention will be described with reference to the accompanying drawings. FIG. 1 (a) is a bottom view showing a first embodiment of the golf club head according to the present invention, and FIG. 1 (b) is a front view showing the golf club head of FIG. 1 (a). ..

As shown in FIG. 1, the golf club head 10 of the present embodiment includes a face portion 11, a sole portion 12, a crown portion 13, a side portion 14, and a hosel portion 15. The side portion 14 orbits the head 10 from the toe side 14a to the heel side 14b via the back side. Further, the face portion 11 and the sole portion 12 are formed adjacent to each other. Although not particularly shown, the inside of the head 10 has a hollow structure, and the inner surface of each part of the head on the hollow structure side is formed to be substantially smooth like the outer surface.

In the present invention, a golf club head 10 having a large volume of 430 cc or more is targeted. A more preferable volume is 435 cc or more. On the other hand, the upper limit of the head volume is 500 cc or less, preferably 470 cc or less. Further, in the present invention, a golf club head 10 having a weight of 220 g or less is targeted. A more preferable weight is 195 g or less. On the other hand, the lower limit of the head weight is 160 g or more, preferably 165 g or more.

In the present embodiment, the area of the sole portion 12 is designed to be wide so that the primary natural frequency of the vibration of the sole portion 12 generated when the golf club head 10 hits the ball is 2400 Hz or less. For example, the area of the sole portion 12 is 4000 mm.²The above is preferable, 6000 mm²The above is more preferable. By significantly increasing the area of the sole portion 12 with respect to the head volume in this way, the amplitude of the sole portion 12 becomes large, and the primary natural frequency of the sole portion 12 can be set to 2400 Hz or less.

The primary natural frequency is preferably 2200 Hz or less, more preferably 2000 Hz or less. The lower limit of the primary natural frequency is preferably 1300 Hz or higher because it may not be preferable that the head volume is too large. On the other hand, if the area of the sole portion 12 is too large, the swing will be hindered, so the area of the sole portion 12 is 14000 mm.²The following is preferable, 13000 mm²The following is more preferable.

The radius of curvature R of the outer surface of the sole portion 12 in the direction from the toe side 14a to the heel side 14b is preferably 150 mm or more, more preferably 160 mm or more. On the other hand, if the radius of curvature R is too large, there is a problem that it becomes difficult for the golfer to set up the head 10 and hold it, so 500 mm or less is preferable, and 450 mm or less is more preferable.

The wall thickness of the sole portion 12 is preferably 0.6 mm or more, more preferably 0.7 mm or more, in order to maintain a constant strength. On the other hand, if it becomes too thick, the weight increases. Therefore, the wall thickness of the sole portion 12 is preferably 1.5 mm or less, more preferably 1.2 mm or less.

In addition, in this specification, a "sole portion" means a portion having a wall thickness different from that of an adjacent side portion or face portion. When the wall thickness of the sole portion is the same as the wall thickness of the side portion or the face portion, the place where the radius of curvature R of the outer surface of the sole portion changes significantly is defined as the boundary with the side portion or the face portion. Further, the "area of the sole portion" means the area of the outer surface of the sole portion.

FIG. 2 is a second embodiment of the golf club head according to the present invention, (a) is a bottom view thereof, and (b) is a front view thereof. As shown in FIG. 2, the golf club head 20 of the present embodiment also includes a face portion 21, a sole portion 22, a crown portion 23, a side portion 24, and a hosel portion 25. In the present embodiment, the side portion 24 is formed between the face portion 21 and the sole portion 22.

In the present embodiment, the radius of curvature R of the outer surface of the sole portion 22 in the direction from the toe side 24a to the heel side 24b is designed to be as large as 230 mm or more so that the primary natural frequency of the sole portion 22 is 2400 Hz or less. ing. The radius of curvature R is more preferably 350 mm or more, and further preferably 400 mm or more. By significantly increasing the radius of curvature R of the sole portion 22 in this way, the shape of the sole portion becomes flat, and the primary natural frequency of the sole portion 22 can be set to 2400 Hz or less. On the other hand, if the radius of curvature R is too large, the above-mentioned problems occur, so 500 mm or less is preferable, and 450 mm or less is more preferable.

In this embodiment, the area of the sole portion 22 does not necessarily have to be increased to 3000 mm.²The above is preferable, 4000 mm²The above is more preferable, 6000 mm²The above is more preferable. The wall thickness of the sole portion 22 is preferably 0.6 mm or more, more preferably 0.7 mm or more, in order to maintain a constant strength. On the other hand, if it becomes too thick, the weight increases. Therefore, the wall thickness of the sole portion 22 is preferably 1.5 mm or less, more preferably 1.2 mm or less.

FIG. 3 is a third embodiment of the golf club head according to the present invention, (a) is a bottom view thereof, and (b) is a front view thereof. As shown in FIG. 3, the golf club head 30 of the present embodiment also includes a face portion 31, a sole portion 32, a crown portion 33, a side portion 34, and a hosel portion 35.

In the present embodiment, the weight 36 is formed on the inner surface of the sole portion 32 on the hollow structure side so that the primary natural frequency of the sole portion 32 is 2400 Hz or less. Since the weight 36 is formed inside the head 30, it is shown by a broken line in FIG. For example, the weight 36 is preferably formed at the position of the antinode of the vibration generated in the sole portion 32 at the time of hitting the head. By forming the weight 36 at the position of the antinode of vibration in this way, the primary natural frequency of the sole portion 32 can be lowered to 2400 Hz or less. The vibration antinode of the sole portion 32 usually occurs at the position of the center of gravity of the sole portion 32 if the wall thickness of the sole portion 32 is uniform.

The weight of the weight 36 is, for example, preferably 3 g or more, and more preferably 4 g or more. On the other hand, if it is too heavy, there are problems such as affecting the swing balance, making the entire head heavier, and reducing the head volume. Therefore, the weight 36 is preferably 10 g or less, and 9 g or less is more. preferable. In addition, the area of the weight 36 in contact with the sole surface 32 is 200 mm in order to properly control the vibration of the sole portion 32.²The following is preferable, 150 mm²The following is more preferable. The lower limit of this area is 20 mm.²The above is preferable.

The shape of the weight 36 is shown in FIG. 3 as a rectangular parallelepiped, but is not particularly limited thereto, and may be, for example, a rectangular parallelepiped, a sphere, an ellipsoid, a cylinder, a cone, a truncated cone, or another polyhedron. .. Further, the weight 36 can be joined to the sole portion 32 in close contact with one surface by welding or the like, or can be integrally formed by casting or the like.

In this embodiment as well as in the second embodiment, it is not always necessary to increase the area of the sole portion 32, and the area is 3000 mm.²The above is preferable, 4000 mm²The above is more preferable, 6000 mm²The above is more preferable. The wall thickness of the sole portion 32 is preferably 0.6 mm or more, more preferably 0.7 mm or more, as in the second embodiment. Further, 1.5 mm or less is preferable, and 1.2 mm or less is more preferable.

FIG. 4 is a fourth embodiment of the golf club head according to the present invention, (a) is a bottom view thereof, and (b) is a front view thereof. As shown in FIG. 4, in this embodiment, the combination of the first and third embodiments, that is, the area of the sole portion 42 is designed to be large, and the weight 46 is formed on the inner surface of the sole portion 42. It was done.

In the present embodiment, the area of the sole portion 42 is 4000 mm.²The above is preferable, 6000 mm²The above is more preferable. By increasing the area of the sole portion 42 and forming the weight 46 on the inner surface of the sole portion 42 in this way, the primary natural frequency of the sole portion 42 can be reduced to 2200 Hz or less, and further to 2000 Hz or less. The upper limit of the area is 14000mm²The following is preferable, 13000 mm²The following is more preferable. The weight 46 is preferably formed at the position of the antinode of the vibration of the sole portion 42. Although one weight 46 is shown in FIG. 4, if the area of the sole portion 42 is increased and vibration antinodes occur at a plurality of positions of the sole portion 42, a plurality of weights 46 are formed. can do.

As described above, in the present invention, the first to third embodiments can be combined. The first and second embodiments are combined to increase the area and radius of curvature of the sole portion, and the second and third embodiments are combined to increase the radius of curvature on the inner surface of the sole portion. Or by combining the first to third embodiments to form a weight on the inner surface of the sole portion with an increased area and radius of curvature, the primary natural frequency of the sole portion can be reduced to 2200 Hz or less. , And even 2000Hz or less.

In any of the embodiments, the face portion, sole portion, crown portion, side portion, hosel portion, and weight can be made of a metal material having the same or different composition. For example, it is preferably made of a titanium alloy or an aluminum alloy, for example, a titanium alloy having a composition of 5.5 to 6.75 wt% Al, 3.5 to 4.5 wt% V, the balance Ti and unavoidable impurities (Ti-6Al- 4V) can be used.

Golf club heads of Examples 1 to 4 and Comparative Examples having the specifications shown in Table 1 were manufactured. In Table 1, the "length" is the distance between the toe and heel of the sole portion, and the "depth" is the distance between the face and back of the sole portion. The appearances of Examples 1 to 4 and Comparative Examples correspond to FIGS. 1 to 5. In both Examples and Comparative Examples, Ti-6Al-4V alloy was used and the head volume was 450 cc. Then, the primary natural frequencies of the sole portions of Examples 1 to 4 and Comparative Examples were determined by FEM analysis. The results are shown in Table 1.

<tables num="1"><img file="JP2010142448A_D0001.tif" /></tables>

Sole area is about 4500mm²As shown in Table 1, the primary natural frequency of the sole portion was very high at about 2700 Hz. On the other hand, the sole area is about 7100 mm²In Example 1 which was widened, the primary natural frequency of the sole portion could be significantly reduced to about 2200 Hz. In addition, the sole area is about 7100 mm²In Example 2 in which the radius of curvature R of the sole was increased to about 400, the primary natural frequency of the sole could be reduced to about 1900 Hz. Even if the sole area was the same as that of the comparative example, in Example 3 in which a weight of 5 g was attached to the antinode of the vibration of the sole portion, the primary natural frequency of the sole portion could be significantly reduced to about 2100 Hz. In addition, the sole area is about 7100 mm²In Example 4 in which a weight of 5 g was attached to the antinode of the vibration of the sole portion, the primary natural frequency of the sole portion could be lowered to about 1800 Hz.

<figref num="1">(a) is a bottom view showing the first embodiment of the golf club head according to the present invention, and (b) is a front view of the golf club head shown in (a).</figref><figref num="2">(a) is a bottom view showing a second embodiment of the golf club head according to the present invention, and (b) is a front view of the golf club head shown in (a).</figref><figref num="3">(a) is a bottom view showing a third embodiment of the golf club head according to the present invention, and (b) is a front view of the golf club head shown in (a).</figref><figref num="4">(a) is a bottom view showing a fourth embodiment of the golf club head according to the present invention, and (b) is a front view of the golf club head shown in (a).</figref><figref num="5">(a) is a bottom view of the golf club head of the comparative example, and (b) is a front view of the golf club head shown in (a).</figref>

Code description

10, 20, 30, 40 Golf Club Head 11, 21, 31, 41 Face 12, 22, 32, 42 sole 13, 23, 33, 43 Crown 14, 24, 34, 44 Sides 15, 25, 35, 45 hosel part 36, 46 weights