JP4946160B2 - Golf club head and golf club - Google Patents

Description

  The present invention relates to a golf club head and a golf club that can reduce the influence of a situation where a golf ball is placed and can obtain a relatively stable flight distance.

One of the functions required of a golf club is to obtain a stable flight distance. In recent years, attempts have been made to improve golf clubs, focusing on the aspect of stabilizing the flight of a golf ball hit in order to obtain a stable flight distance.
For example, by providing a score line with a groove having a concave cross section on the face surface of the golf club in the toe-heel direction of the golf club, the friction force received by the face surface and the golf ball at the time of hitting is increased. The amount of spin has been increased.
It is believed that an increase in the backspin amount results in a relatively stable flight of the golf ball, resulting in a stable flight distance.

On the other hand, it has been found that, particularly when used for anything other than a tee shot, it is generally affected by the flight of a hit ball depending on the situation where a golf ball called a lie is placed. Here, the impact on the flight of the hit ball is, in addition to the absolute effect such as increase or decrease of the flight distance, the possibility of flight that cannot be predicted, that is, when the ball is hit in the same situation (condition) Nevertheless, the flight distance varies.
In particular, when foreign matter such as moisture, grass, or soil intervenes between the golf ball and the face surface when hitting a ball, the frictional force that the face surface and the golf ball receive when hitting the ball tends to decrease, and the backspin amount is reduced. I know that

In addition, it has been found that the degree of backspin amount is uncertain and the possibility of flying is likely to be unpredictable.
Even under such circumstances, by providing a score line in only one direction of the toe-heel direction of the golf club, foreign matter intervening at the time of hitting can be eliminated to some extent, but it adversely affects the flight of the hit ball. It was not possible to reduce to a certain extent, and the score line alone was not enough to remove foreign substances.
Therefore, various golf clubs having a function of eliminating foreign matters intervening at the time of hitting are disclosed (for example, see Patent Documents 1 to 3).

Patent Document 1 discloses a golf club having a face provided with a groove perpendicular to the sole.
Patent Document 2 discloses a golf club in which a radial face groove is provided on a face surface. In the golf club of Patent Document 2, a radial face groove prevents a water film from being formed between the face surface and the ball, thereby preventing a hydroplaning phenomenon. Thereby, in the golf club of patent document 2, a flight distance and directionality can be stabilized.

  Further, Patent Document 3 discloses a golf club in which a large number of face grooves are formed in a polygonal shape around the sweet spot area on the face surface. In the golf club of Patent Document 3, when a golf ball in a lawn or a rough is hit by a face groove formed in a polygonal shape and rains in the rain, the sweet spot area In addition, moisture is not guided, and a water film is prevented from being formed between the face surface and the ball, thereby preventing a hydroplaning phenomenon. Thus, in the golf club of patent document 3, a flight distance and directionality can be stabilized.

Japanese Utility Model Publication No. 1-90574 Japanese Patent No. 3555774 JP-A-8-777

  However, foreign substances intervening between the golf ball and the face surface include grass or soil in addition to moisture. For example, it has been found by the inventor's examination that fibrous grasses and the like enter a groove portion (concave portion) of a score line at the time of hitting and then stay and cannot be eliminated. For this reason, even if it is a structure of the head of the golf club disclosed by the above-mentioned patent document 1-patent document 3, there exists a problem that the capability to exclude the grass etc. which entered at the time of hitting is still inadequate. As described above, there is not sufficient capability to exclude grass or soil other than moisture intervening between the golf ball and the face surface at the time of hitting.

  An object of the present invention is to solve the above-described problems of the prior art, and effectively eliminates foreign matter such as moisture, grass or soil that intervenes between the golf ball and the face surface at the time of hitting. It is an object of the present invention to provide a golf club head and a golf club that can obtain a relatively stable flight distance without being influenced by the situation in which the golf ball is placed.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a golf club head having a face surface for hitting a golf ball, wherein the face surface is formed at a predetermined loft angle. A first groove group in which a plurality of first grooves each having a depth of 200 to 600 μm and a width of 250 to 1000 μm are formed on the surface; and a depth of 5 to 50 μm and a width on the face surface. A second groove group in which a plurality of second grooves of 5 to 100 μm are formed, and the total length of the first grooves of the first groove group is 250 to 1200 mm. The total length of each second groove in the second groove group is 100 to 1200 mm, and further, a horizontal virtual line on the first groove and the face surface of the first groove group. The angle α between the second groove group and the angle α is 0 ° to 15 °. It is to provide a golf club head, wherein the angle between the second groove and said horizontal virtual line β is 45 ° to 90 °.

In the present invention, the depth of the first groove is preferably 300 to 600 μm, and the width of the first groove is preferably 400 to 1000 μm.
Moreover, in this invention, it is preferable that the depth in a 2nd groove | channel is 5-35 micrometers, More preferably, it is 5-25 micrometers.
Moreover, in this invention, it is preferable that the width | variety of a 2nd groove | channel is 5-60 micrometers, More preferably, it is 5-40 micrometers.
Moreover, in this invention, it is preferable that the total length of the length of each 1st groove | channel of a 1st groove group is 400-1200 mm. Further, it is preferable that the total length of the second grooves of the second groove group is 200 to 1200 mm.
Furthermore, the angle α between the first groove of the first groove group and the horizontal imaginary line on the face surface is preferably 0 ° to 5 °. Further, the angle γ formed by the first groove of the first groove group and the second groove of the second groove group is preferably 60 ° to 90 °.

In this invention, it is preferable that the arrangement | positioning space | interval of each said 1st groove | channel in the said 1st groove group is 1.5-4.0 mm.
Moreover, in this invention, it is preferable that the arrangement | positioning space | interval of each said 2nd groove | channel in the said 2nd groove group is 1.0-6.0 mm.
Furthermore, in the present invention, it is preferable that the first groove and the second groove have a curvature radius of 500 mm or more.

Further, in the present invention, when the face surface is arranged on a horizontal plane so as to have the predetermined loft angle, a perpendicular line passing through the center of gravity of the golf club head and perpendicular to the face surface intersects the face surface. When the height of the center of gravity reaching F is F _GH (mm), the center of gravity height F _GH is preferably 22 mm or less.
Furthermore, in the present invention, the loft angle is preferably 45 ° or more.

  According to a second aspect of the present invention, there is provided a golf club comprising the golf club head according to the first aspect of the present invention.

  According to the golf club head of the first aspect of the present invention and the golf club of the second aspect of the present invention, the first groove having a depth of 200 to 600 μm and a width of 250 to 1000 μm is formed on the face surface. A plurality of first groove groups formed, and a second groove group formed by forming a plurality of second grooves having a depth of 5 to 50 μm and a width of 5 to 100 μm are provided. The total length is 250 to 1200 mm, the total length of the second grooves is 100 to 1200 mm, and the angle α is set to 0 ° to the horizontal imaginary line on the face surface of the first groove of the first groove group. By setting the angle β between the second groove of the second groove group and the horizontal imaginary line to be 45 ° to 90 °, the golf ball is hit between the golf ball and the face surface. Effectively eliminate foreign substances such as moisture, grass, or soil that intervene Can, consequently it is possible to obtain a relatively stable flight distance without the golf ball is dependent on the placed circumstances. In particular, even when the length of turf, which is generally called semi-rough, is long, foreign matter such as grass or soil can be effectively removed, and it is relatively stable compared to the case of hitting on a fairway. Flying distance can be obtained.

  Hereinafter, a golf club head and a golf club of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

At present, when a golf ball is hit, there is no golf club having sufficient ability to exclude grass, soil, and the like other than moisture intervening between the golf ball and the face surface.
In the golf club, a first groove group in which a plurality of first grooves each having a depth of 200 to 600 μm and a width of 250 to 1000 μm are formed, and a first groove group having a depth of 5 to 50 μm and a width of 5 to 100 μm. A second groove group in which a plurality of grooves are formed on the face surface, and the total length of the first grooves in the first groove group is 250 to 1200 mm. When the second groove group has a depth or width larger than the above range as a result of the present inventors diligently examining the total length of each second groove of 100 to 1200 mm, That is, when the 1st groove group and the 2nd groove group were comparatively big groove parts, it discovered that stability of flight distance was spoiled by conditions.

  In particular, when a golf ball placed in a long grass is hit, moisture, grass, soil, etc. intervening between the golf ball and the face surface, and surrounding water, grass, soil, etc., pass through the groove. The priority is lost in the direction of exiting, and the main reason is that the grass mainly stays among them, and the hit ball becomes unstable and the stability of the flight distance is impaired. For example, grass is mainly caught at the edge where relatively large grooves intersect. Thus, if the first groove group and the second groove group are relatively large groove portions, the grass cannot be excluded.

  As described above, as a result of the diligent study by the present inventors, in general, the larger the groove portion, the greater the point that it is considered that there is an effect of eliminating foreign matters. The present invention has been achieved by paying attention not only to let a certain grass or the like enter the groove but also to quickly remove it so as not to stay.

  In the present invention, a first groove group in which a plurality of first grooves having a depth of 200 to 600 μm and a width of 250 to 1000 μm are formed, and a depth of 5 to 50 μm and a width of 5 to 100 μm. A second groove group in which a plurality of second grooves are formed is formed on the face surface, and has a relatively large first groove group and a relatively small second groove group. The total length of the first grooves in the first groove group is 250 to 1200 mm, and the total length of the second grooves in the second groove group is 100 to 1200 mm. Furthermore, the angle of the first groove of the first groove group is 0 ° to 15 °, and the first groove having a deep and wide width is formed in the lateral direction. In this way, by forming the relatively large first groove group in the lateral direction and further forming the angle of the second groove of the relatively small second groove group on the face surface at 45 ° to 90 °. The present invention has been made by finding that a golf club capable of obtaining a relatively stable flight distance regardless of conditions can be provided.

FIG. 1 is a schematic plan view showing a first embodiment of a golf club having a golf club head of the present invention.
As shown in FIG. 1, the golf club 10 has a golf club head 12, a socket 14, a golf club shaft 16, and a grip 18.
In the golf club 10, a golf club shaft 16 is attached to a hosel portion 24 of the golf club head 12 via a socket 14. The golf club shaft 16 has a grip 18 attached to the opposite side to which the golf club head 12 is attached.

  The golf club head 12 is a type of head generally called an iron, and has a face portion 20, a sole portion 22 and a hosel portion 24. In the golf club head 12, the face portion 20, the sole portion 22 and the hosel portion 24 are integrally formed.

The surface of the face portion 20 is a face surface 20a for hitting a golf ball. The sole portion 22 is provided below the face portion 20 continuously.
In the golf club head of the present embodiment, the loft angle θ (see FIG. 6) is preferably 45 ° or more. This loft angle will be described in detail later.

Further, the face length in the face portion 20, that is, the length from the rearmost end of the heel portion of the golf club head 12 to the rearmost end of the toe portion is not particularly limited, and is a size of a general golf club head. From about 70 to 130 mm.
The face length in the face portion 20 is the position where the rearmost end of the heel portion of the golf club head 12 is 22.23 mm above the reference surface when the golf club head 12 is set at a normal address position on the reference surface. The distance in the direction of a plane that includes the shaft axis and is perpendicular to the reference plane when the rearmost end of the toe part is the most overhanging position.

Further, the face height in the face portion 20, that is, the length from the rearmost end of the sole portion of the golf club head 12 to the rearmost end of the crown portion or the top blade portion is not particularly limited. It is about 35 to 75 mm from the size of the club head.
The face height in the face portion 20 is that when the golf club head 12 is set to a normal address position on the reference surface, the sole end of the golf club head 12 is grounded to the sole surface of the sole portion. It is the distance in the vertical direction when the rear end of the crown part or the top blade part is the most protruding position.

  The hosel portion 24 fixes the golf club shaft 16 to the golf club head 12 and is integrally provided on the heel side of the face portion 20. The hosel portion 24 is provided with an opening (not shown) into which the golf club shaft 16 is inserted. The golf club shaft 16 is fixed to the golf club head 12 via a socket 14. The golf club shaft 16 does not necessarily have to be fixed to the golf club head 12 via the socket 14, and some golf clubs have no socket and the golf club shaft is directly fixed to the golf club head. .

  In the present embodiment, first grooves 32a to 32f (score lines) extending in the toe direction from the heel are formed in parallel on the face surface 20a of the face portion 20, respectively. Further, a plurality of second grooves 34a different from the first grooves 32a to 32f are formed on the face surface 20a so as to be orthogonal to the first grooves 32a to 32f.

  In the present embodiment, the first groove group 32 is constituted by the plurality of first grooves 32a to 32f, and the second groove group 34 is constituted by the plurality of second grooves 34a.

As shown in FIG. 3, each groove 32a~32f the first groove group 32 is parallel to the horizontal imaginary line _{H L} on the face 20a. That is, the angle α formed by each of the grooves 32a to 32f of the first groove group 32 and the horizontal virtual line _HL is 0 °. In the present invention, the angle α formed between the grooves 32a to 32f of the first groove group 32 and the horizontal imaginary line _HL is set to 0 ° to 15 °. Preferably, the angle α is 0 ° to 5 °.
Here, the horizontal virtual line H _L in the present invention, since the installation surface plane H _p parallel to (the horizontal plane H) and the face surface 20a and intersects the line in the case of setting the golf club at normal address position is there. The horizontal virtual line _HL will be described later in detail.

In the present invention, the angle α formed by each of the first grooves 32a to 32f of the first groove group 32 and the horizontal imaginary line _HL is set to 0 ° to 15 °. Removes foreign matter such as moisture, grass, or soil intervening between the golf ball and the face surface, and can obtain a relatively stable flight distance without being influenced by the surrounding conditions (situation) of the golf ball. It becomes possible. In particular, even in a case where the grass is a little bit, generally called semi-rough, for example, when the turf length is about 40 mm, the fairway, for example, the turf length is about 20 mm. Compared to such a case, a relatively stable flight distance can be obtained.
In the present invention, in the first grooves 32a to 32f corresponding to 80% or more of the total length of the first grooves 32a to 32f in the first groove group 32, the angle α formed with the horizontal virtual line _HL is 0. The angle is preferably from 15 ° to 15 °, more preferably 100%.

Each second groove 34a of the second groove group 34 is formed perpendicular to the horizontal imaginary line _HL on the face surface 20a. That is, the angle β formed by each groove 34a of the second groove group 34 and the horizontal imaginary line _HL is 90 °. In the present invention, the angle β formed by each groove 34a of the second groove group 34 and the horizontal imaginary line _HL is set to 45 ° to 90 °.

In the present invention, the angle β formed by all the grooves 34a on the face surface 20a with the horizontal imaginary line _HL is set to 45 ° to 90 °, so that the golf ball and the face surface can be more effectively hit when hit. It is possible to eliminate foreign matter such as moisture, grass, or soil intervening during this period, and to obtain a relatively stable flight distance without being influenced by the situation where the golf ball is placed.
In the present invention, in the second groove 34a corresponding to 80% or more of the total length of the second groove 34a in the second groove group 34, the angle β formed with the horizontal virtual line _HL is 45 ° to 45 °. It is preferably 90 °, more preferably 100%.

Further, as shown in FIG. 3, the first groove 32a (32b to 32f) of the first groove group 32 and the second groove 34a of the second groove group 34 are orthogonal to each other. The angle γ is 90 °.
In the present invention, the angle γ is the smaller of the angles formed by the first groove 32a (32b to 32f) of the first groove group 32 and the second groove 34a of the second groove group 34. The angle (one of 90 ° or less). Further, an angle γ formed by the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 is different from that of the first groove group 32 on the face surface 20a. This is an angle formed by the second groove group 34, and the angle γ is preferably 45 ° to 90 °. The angle γ is more preferably 60 ° to 90 °.
In the present invention, the angle γ formed by the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 is set to 45 ° to 90 °, so that it is more effective. In particular, it removes foreign matter such as moisture, grass, or soil that has intervened between the golf ball and the face surface at the time of hitting the ball, and has a relatively stable flight distance without being affected by the conditions on which the golf ball is placed. It becomes possible to obtain.

Further, as shown in FIG. 4, the first groove 32a is one with a rectangular cross section, the first groove 32a has a depth _{h 1} is 200 to 600 [mu] m, the width _{W 1} 250～1000Myuemu It is. The first grooves 32b to 32f other than the first groove 32a have the same configuration, and the first groove 32a will be described as a representative, and description of the other first grooves 32b to 32f will be omitted.

The second groove 34a has a rectangular cross section, and the second groove 34a has a depth h ₂ of 5 to 50 μm and a width W _{2 of} 5 to 100 μm.
The depth _{h 2} of the second groove 34a is preferably 5 to 35 m, more preferably 5 to 25 [mu] m.
Furthermore, the width W2 of the _second groove 34a is preferably 5 to 60 μm, and more preferably 5 to 40 μm.
In the present invention, the second groove 34a is formed so that the second groove 34a is orthogonal to the first groove 32a and a part of the first groove 32a is notched. The first groove 32a is wider and deeper than the second groove 34a.

In the present invention, the first groove 32a (32b to 32f) has a depth h ₁ of 200 to 600 μm and a width W ₁ of 250 to 1000 μm.
Further, in the first groove 32a of the present invention (32b~32f), the upper limit of the depth _{h 1} and width _{W 1,} although not particularly limited, in the present invention, to more efficiently hitting Therefore, the upper limit value of the depth h ₁ is set to 600 μm, and the upper limit value of the width W ₁ is set to 1000 μm. The first groove 32a of the present invention (32b~32f), the depth _{h 1} is 600 .mu.m, when the width _{W 1} is larger than 1000μm, the unevenness of the face surface is relatively large with respect to the golf ball, hitting Sometimes it can have an adverse effect.

The first groove 32a of the present invention (32b~32f), the depth _{h 1} is 200 to 600 [mu] m, when the width _{W 1} is less than the range of 250～1000Myuemu, effectively, the golf ball and the face surface at the time of hitting Foreign matter such as water, grass, or soil intervening during the period cannot be excluded. For this reason, a relatively stable flight distance cannot be obtained without being influenced by the condition where the golf ball is placed.

On the other hand, in the first groove 32a (32b to 32f) of the present invention, when the depth h ₁ is larger than the range of 200 to 600 μm and the width W ₁ is larger than the range of 250 to 1000 μm, the unevenness of the face surface is It becomes relatively large and may adversely affect the shot.

In the present invention, the second groove 34 a has a depth h ₂ of 5 to 50 μm and a width W _{2 of} 5 to 100 μm.
When the depth h ₂ is 5 to 50 μm and the width W ₂ is smaller than the range of 5 to 100 μm, the second groove 34a of the present invention effectively intervenes between the golf ball and the face surface at the time of hitting. Foreign matter such as moisture, grass or soil cannot be excluded. For this reason, a relatively stable flight distance cannot be obtained without being influenced by the condition where the golf ball is placed.

On the other hand, when the depth h ₂ is larger than the range of 5 to 50 μm and the width W ₂ is 5 to 100 μm, the second groove 34a according to the present invention has moisture, grass, intervening between the golf ball and the face surface. Priorities are lost in the direction in which the soil and the surrounding water, grass, soil and the like are removed through the groove, and the foreign matter stays in the second groove. Furthermore, foreign matter may remain at the edge where the grooves intersect. For this reason, the foreign substance removal capability is reduced. As a result, a relatively stable flight distance cannot be obtained without being influenced by the condition where the golf ball is placed.

In the present invention, the width W ₁ and the depth h _{1 of the first} groove 32a and the width W ₂ and the depth h ₂ of the second groove 34a are, for example, a contact type surface roughness measuring machine (for example, a corporation) Using Mitutoyo Surf Test SJ-301), each groove portion of the first groove 32a and the second groove 34a is measured one by one with respect to the long side of each groove portion or the cross-sectional direction perpendicular to the virtual center line. It is obtained.
In the present invention, the width W ₂ of width W ₁ and the second grooves 34a of the first groove 32a on the basis of the measured chart by meter, which was determined by internal rules of the R & A "30 degrees measurement rule" is there.
The depth h ₂ of the first groove 32a of the depth h ₁ and second grooves 34a was maximum height measured by the measuring instrument.

The reference of the angles α and γ in the first groove 32a is that when the first groove 32a is parallel and the long sides 100a constituting the first groove 32a are parallel, the long side 100a is the angle α. And γ. On the other hand, when the first groove 32a is non-linear, or when the long side 100a constituting the first groove 32a is nonparallel, the long side 100a of the first groove 32a is not a reference for the angle. , the virtual central line C ₁ calculated in the first groove 32a, substituting the imaginary center line C ₁ angle alpha, the criteria of gamma.
Imaginary center line C ₁ intersects the points of vertical bisector and the end of the edges of each end of the short side 100b direction of the first groove, calculated at both longitudinal ends of the first groove , Indicated by a line connecting both ends.

In addition, the standard of the angles β and γ in the second groove 34a is that when the second groove 34a is parallel and the long sides 102a constituting the second groove 34a are parallel, the long side 102a is angle β And γ. On the other hand, when the second groove 34a is non-linear, or when the long side 102a constituting the second groove 34a is non-parallel, the long side 102a of the second groove 34a is not a reference for the angle. , the virtual center line C ₂ calculated in the second groove 34a, substituting the imaginary center line C ₂ angle beta, the criteria of gamma.
Imaginary center line C ₂ intersects the points of vertical bisector and the end of the edges of each end of the short side 102b direction of the second groove, calculated at both longitudinal ends of the second groove , Indicated by a line connecting both ends.

In the present invention, it is preferable that the first grooves 32a to 32f have the same cross-sectional shape. Since the cross-sectional shape does not change without changing the depth or width, foreign matters such as grass or soil can be quickly removed, and a more stable flight distance can be obtained.
Furthermore, it is preferable that the cross-sectional shape of the second groove 34a does not change similarly to the first grooves 32a to 32f. Even in the second groove 34a, since the cross-sectional shape does not change, foreign matters such as grass or soil can be quickly removed, and a more stable flight distance can be obtained.

In the present invention, the arrangement interval of the first grooves 32a to 32f of the first groove group 32 is preferably 1.5 to 4.0 mm. An arrangement | positioning space | interval is the distance of the edge parts of each 1st groove | channel 32a-32f, if the 1st groove | channels 32a-32f are mutually parallel. On the other hand, if the first grooves 32a to 32f are not parallel to each other, a close distance is set as an arrangement interval among the distances between adjacent grooves.
In the present invention, the arrangement interval of the first grooves 32a to 32f of the first groove group 32 is set to 1.5 to 4.0 mm, so that the golf ball and the face surface are more effectively hit when hit. Foreign matter such as moisture, grass, or soil intervening in the meantime can be eliminated, and a relatively stable flight distance can be obtained without being influenced by the situation (condition) on which the golf ball is placed.
The first grooves 32a to 32f of the first groove group 32 are preferably parallel to each other. Thereby, foreign matters, such as grass or soil, can be removed more rapidly.
In the present invention, it is preferable that five or more first grooves having an arrangement interval of 1.5 to 4.0 mm are provided, and more preferably, the arrangement intervals of all the first grooves are 1. .5 to 4.0 mm.

Moreover, in this invention, it is preferable that the arrangement | positioning space | interval of each 2nd groove | channel 34a of the 2nd groove group 34 is 1.0-6.0 mm.
In the present invention, the arrangement interval of the second grooves 34a of the second groove group 34 is set to 1.0 to 6.0 mm, so that it is more effective between the golf ball and the face surface at the time of hitting. It is possible to eliminate a foreign matter such as intervening moisture, grass, or soil, and to obtain a relatively stable flight distance without being influenced by the situation (condition) on which the golf ball is placed.
The second grooves 34a of the second groove group 34 are also preferably parallel to each other. Thereby, foreign matters, such as grass or soil, can be removed more rapidly.
Furthermore, the second grooves 34a of the second groove group 34 may be formed to overlap each other in addition to being parallel.
In the present invention, it is preferable that five or more second grooves having an arrangement interval of 1.0 to 6.0 mm are provided, and more preferably, the arrangement intervals of all the second grooves are 1. 0.0 to 6.0 mm.

Moreover, in each of the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34, it is preferable that the curvature radius is 500 mm or more. More preferably, the radius of curvature is 900 mm or more, and the most preferable is a straight line having an infinite curvature radius. That is, it is most preferable that the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 are respectively straight lines.
In other words, in the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34, the straightness may be 1 mm or less, respectively. Preferably, it is 0.5 mm or less, and most preferably a straight line with a straightness of 0 mm. This straightness is specified, for example, in JIS B0621-1984.

In the present invention, the curvature radii (straightness) of the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 are set in the above-described range. Effectively eliminates foreign matter such as moisture, grass, or soil that has intervened between the golf ball and the face surface at the time of hitting the ball, and is relatively stable without being influenced by the situation (condition) where the golf ball is placed. Can be obtained.
In the present invention, the radius of curvature and straightness are determined by measuring the edge of each groove in the long side direction.
Furthermore, in the present invention, with respect to the first groove group 32 and the second groove group 34, grooves corresponding to 80% or more of the total length of each groove group are within the above-mentioned range with respect to the radius of curvature (straightness). It is preferable that it is 100%.

Further, the center of gravity height F _GH of the golf club head 12, which will be described in detail later, is from a horizontal plane H at a point g where a vertical line L passing through the center of gravity G of the golf club head 12 and orthogonal to the face surface 20 a intersects the face surface 20 a. It is the height of. The height of the center of gravity _{F GH} is preferably at 22mm or less.

In the present invention, the effect is manifested particularly in a golf club having a relatively low center of gravity position where the center of gravity height _FGH is 22 mm or less.
Generally, when a ball is hit with a relatively long grass, the hit position tends to be upward. In this case, in a golf club having a relatively low center of gravity, there is a high possibility of hitting at a portion above the center of gravity. When the ball is hit at a portion above the center of gravity, the backspin amount is reduced due to the gear effect. As described above, when a ball is hit with a relatively long grass, there is a high possibility that foreign matter such as moisture, grass or soil will intervene between the golf ball and the face surface when the ball is hit. When intervening, the amount of backspin decreases. For this reason, as a result, the backspin amount is further reduced. Thereby, the hit ball will fly more unstable, and the flying distance is likely to be unstable. For this reason, in order to suppress a decrease in the backspin amount, a golf club having a center-of-gravity height _FGH of 22 mm or less is more preferably configured as the golf club of the present invention.
In the present invention, the lower limit value of the center of gravity height _FGH is not particularly limited, but about 10 mm is considered to be the lower limit value depending on the shape and mass distribution of the golf club head.

In the present invention, the golf club having a loft angle θ of 45 ° or more is more effective. In a golf club having a loft angle θ of 45 ° or more, a particularly required function is to obtain a stable flight distance. Therefore, a golf club having a loft angle of 45 ° or more is a golf club that has a particularly large backspin amount, greatly contributes to controlling the flight distance by backspin, and has a relatively stable flight distance. When such a golf club hits a ball with a relatively long grass, a desired backspin amount cannot be obtained, and an unexpected variation in flight distance, that is, a relatively longer flight distance Is likely to become unstable. For this reason, the golf club of the present invention is preferably configured in order to suppress a decrease in the backspin amount.
In the present invention, the upper limit value of the loft angle is not particularly limited, but about 70 ° is considered to be the upper limit value depending on the shape and required performance of the golf club head.

In the present invention, the formation positions of the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 on the face surface 20a are not particularly limited. .
In addition, another groove or other groove group that does not fall within any range of the first grooves 32a to 32f of the first groove group 32 and the second groove 34a of the second groove group 34 in the present invention is further provided. It may be formed.

In the present invention, the formation positions of the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 are, for example, ranges defined by golf rules. It can form suitably in the inside.
Further, for the purpose of decoration, the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34 may be appropriately formed. Furthermore, for example, linear grooves are formed in parallel as a general form in which each groove group is effectively arranged within a range defined in the golf rules. In this case, particularly in the case of an iron golf club, since the face surface is trapezoidal, a parallel groove having the same length is formed from the sole side of the face surface to a certain position, and above the certain position. Can be formed so as to gradually shorten as the groove becomes the upper part.
Furthermore, in the golf club of the present invention, in addition to the first grooves 32a to 32f of the first groove group 32 and the second grooves 34a of the second groove group 34, other grooves on the face surface, and A punch mark may be provided.

  In the present invention, the length of the first grooves 32a to 32f of the first groove group 32 and the length of the second groove 34a of the second groove group 34 are the most in each groove. It is defined by the length of the long side. In the present invention, the length of the groove is preferably 15 mm or more. The upper limit of the groove length is defined by the size of the golf club head and the like, and is about 130 mm.

Furthermore, in the present invention, the total length of the first grooves 32a to 32f of the first groove group 32 is 250 mm to 1200 mm. Moreover, in this invention, the total length of the 2nd groove | channel 34a of the 2nd groove group 34 is 100 mm-1200 mm. Note that the upper limit of the total length is defined by the size of the golf club head and the like.
In the present invention, the total length of the first grooves 32a to 32f of the first groove group 32 is preferably 400 to 1200 mm. Furthermore, the total length of the second grooves 34a of the second groove group 34 is preferably 200 to 1200 mm.

Moreover, in this invention, it is not limited to the structure of a 1st groove group and a 2nd groove group as shown in FIG. For example, as shown in FIG. 5, as in the first groove group 36, the angle α formed with the horizontal virtual straight line _HL may be 0 ° or more. In this case, the angle γ formed by the first groove group 36 (first groove 36a) and the second groove group 34 (second groove group 34a) is 45 ° to 90 °.

Hereinafter, a method for measuring the center-of-gravity height _FGH will be described in detail.
As shown in FIG. 6, the center of gravity height F _GH defines a point g where a perpendicular L perpendicular to the face surface 20 a passing through the center of gravity G intersects the face surface 20 a, and the face surface 20 a is set on the golf club head 12. This is the height from the horizontal plane H to the point g when the golf club 10 is placed at the normal address position on the horizontal plane H when the golf club 10 is placed on the horizontal plane H so as to have a predetermined loft angle θ.

Here, when the golf club 10 is installed at the normal address position, the golf club head 12 is installed at the lie angle, and the shaft axis S and the leading edge 13a of the golf club 10 are mutually connected as shown in FIG. Installation means that they are parallel, that is, the face angle is 0 °.
FIG. 7 is a schematic view for explaining a state in which the golf club is installed at the address position, and shows a view as seen from above the horizontal plane H.

Further, the installation according to the lie angle means that the clearance between the round of the sole portion 22 and the horizontal plane H in FIG. 2 is set to be substantially equal on the toe side and the heel side (hosel portion 24 side). . When the round of the sole portion 22 is unclear, when the angle α of the first groove group formed on the face surface 20a is 0 °, the first groove of the first groove group is in the horizontal plane H. You may install so that it may become parallel. Incidentally, the score line in most golf clubs, that is, the first groove group (first groove) of the present invention is designed so that the angle α is 0 °. As long as α does not indicate that it is other than 0 °, the angle α may be regarded as 0 °.
When the round of the sole portion 22 is unclear and the score line is not linear, for example, the parallel to the horizontal plane H cannot be determined, the lie angle is lie angle (degrees) = (100−club length (inch). ). For example, if the club length is 40 inches, the lie angle is 100−40 = 60 °.

Here, the club length is measured by a measuring method defined by the Japan Golf Equipment Association. An example of the measuring device is Club Major II manufactured by Kamoshita Seikosho Co., Ltd. That is, the distance between the end on the heel side and the grip end is the club length.
At the address position, the direction of the leading edge 13a is set to a direction perpendicular to the direction indicated by the face surface 20a.

  As described above, the direction of the face surface 20a is specified, and the golf club head dimensions are measured with the normal address position set. This is possible with a measuring instrument such as a club angle measuring instrument or a golf club gauge manufactured by Golf Smith. Such a measuring device may be any known one, and is not particularly limited in the present invention.

On the other hand, the point g that defines the above-described center-of-gravity height _FGH is obtained by a center-of-gravity measuring instrument 40 as shown in FIG. The center-of-gravity measuring instrument 40 includes a support part 42 that supports the center-of-gravity measurement object at the top, and the support part 42 can know the position of the measurement object that supports the measurement object in equilibrium. That is, in the method of measuring the center of gravity, as shown in FIG. 9A, the golf club head 12 is placed on the support portion 42 and an equilibrium position that does not fall even if the hand is released is searched for. That is, as shown in FIG. 9A, if the point g is included in the contact portion between the face surface 20a and the support portion 42, the golf club head 22 will not fall even if it is released on the support portion 42 and released. As shown in FIG. 9B, if the point g is not included in the contact portion between the face surface 20a and the support portion 42, the golf club head 12 falls when it is put on the support portion 42 and released. Using this, the point g is obtained.

It is preferable that the support part 42 is a form supported on a plane or at three or more points. Moreover, it is preferable that the area of the support part 42 is 15 mm < ² > or less. The lower limit is not particularly limited as long as the golf club head is supported. The area of the support part 42 is indicated by the area of the plane part if it is a plane, or by the area of a figure connecting the points if it is supported by three or more points. By setting the area of the support portion within the above range, the point g can be obtained more accurately.

  The plane supported by the support portion 42 is preferably horizontal or substantially horizontal. Here, “substantially horizontal” means that the inclination with respect to the horizontal plane is within 2 °, preferably within 1 °. As shown in FIG. 10, for example, as shown in FIG. 10, a flat plate 44 is placed on and supported by a support portion 42 and a level 46 is placed on the flat plate 44 to confirm and adjust. can do. By setting within the above range, the point g can be obtained more accurately.

  Further, the loft angle θ (°) referred to in the present invention is an angle formed between the shaft axis S and the face surface 20a as shown in FIG. 6, and is measured by a loft angle measuring device 50 as shown in FIG. The FIG. 11 shows an example in which the golf club 10 of the present embodiment is attached to the loft angle measuring device 50, and FIG. 12 shows the periphery of the golf club head 12 in FIG. 11 in an enlarged manner.

  The measurement of the loft angle θ is performed by adjusting the attachment angle in the lie angle adjustment unit 53 so that the golf club 10 is installed at the lie angle with respect to the reference plane 52 in a state where the golf club 10 is attached to the loft angle measuring device 50. Then, the golf club 10 attached to the loft angle measuring device 50 is arranged so that the sole portion 22 is in contact with the reference surface 52 and the face surface 20a is in close contact with the front end portion 56a of the face angle adjuster 56. That is, the golf club 10 is fixed by the chuck portion 58 so that the face angle is 0 °, that is, a normal address position.

Thereafter, as shown in FIG. 13, the loft angle θ is measured by using a protractor 60 that stands vertically to the reference surface 52 of the face surface 20 a of the golf club head 12. When the face surface 20a is a flat surface, the loft angle θ is obtained by the above measurement.
As described above, the loft angle θ can be measured by inserting a shaft pin into a single golf club head as well as by using a golf club. The numerical value of the loft angle θ obtained by measuring with a single golf club head is substantially the same as the loft angle θ obtained by measuring with the above-described golf club.

  Such a measuring device for the loft angle θ may be a known one that is commercially available, for example, as in the case of the above-described dimension measurement. And a measuring device such as a golf club angle measuring device and a golf club gauge manufactured by Golf Smith. Such a measuring device may be any known one, and is not particularly limited in the present invention.

As described above, in the golf club head 12 of the present embodiment and the golf club 10 using the golf club head 12, the first having a depth of 200 to 600 μm and a width of 250 to 1000 μm on the face surface 20a. The first groove group 32 is formed by forming a plurality of grooves 32a to 32f. In addition, a second groove group 34 is formed on the face surface 20a. The second groove group 34 includes a plurality of second grooves 34a each having a depth of 5 to 50 μm and a width of 5 to 100 μm. Furthermore, the angle α between the horizontal imaginary line _{H L} on the first groove 32a~32f and face 20a of the first groove group 32 and 0 ° to 15 °, the grooves 34a of the second groove group 34 And the horizontal phantom line _HL is set to 45 ° to 90 ° so that foreign matter such as moisture, grass, or soil that intervenes between the golf ball and the face surface at the time of hitting the ball effectively As a result, a relatively stable flight distance can be obtained without depending on the situation where the golf ball is placed.

  Thus, in the present invention, grass is mainly excluded by the relatively large first groove, and moisture, soil, and the like are excluded by the relatively small second groove. In this case, moisture, soil, etc. often ooze out from between the grasses, and the relatively small second groove as in the present invention acts as a bypass, so that moisture, soil, etc. oozed out. Is effectively eliminated. Due to the action of the first groove and the second groove, foreign matters intervening between the golf ball and the face surface can be more effectively eliminated. For this reason, in the present invention, a relatively stable flight distance can be obtained without being influenced by the situation where the golf ball is placed.

  In the present invention, in order to reliably exhibit the above-described effect, when the golf ball is hit, the first groove portion and the second groove portion are present in the contact portion between the golf ball and the face surface, or It is desirable for the golf ball to contact a portion where the first groove and the second groove intersect. According to the present invention, regardless of where the ball is hit on the face surface, the contact portion where the golf ball and the face surface come in contact has the first groove portion and the second groove portion, or the first groove There is a portion where the second groove intersects. For this reason, as described above, a relatively stable flight distance is obtained without being influenced by the situation where the golf ball is placed, that is, the average is stable without being influenced by the situation where the golf ball is placed. It is possible to obtain the flying distance.

Next, a second embodiment of the present invention will be described.
FIG. 14 is a schematic plan view showing a second embodiment of the golf club having the golf club head of the present invention, and FIG. 15 is an enlarged view of a main part of the golf club head of the second embodiment shown in FIG. is there. In the golf club 10a shown in FIG. 14, the grip 18 (see FIG. 1) is not shown.
In the present embodiment, the same components as those of the golf club of the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 14 and FIG. 15, the golf club 10a (golf club head 12a) of the present embodiment is different in the configuration of the second groove group 70 from the golf club 10 of the first embodiment. Since the configuration other than that is the same as that of the golf club 10 of the first embodiment, a detailed description thereof will be omitted.
In the golf club 10a (golf club head 12a) of the present embodiment, as each of the second grooves 70a of the second groove group 70 goes upward from the sole portion 22, the heel side (hosel portion 24 side) to the toe side It is formed so as to extend obliquely toward. Each of the second grooves 70a of the second groove group 70 has an angle β with the horizontal imaginary straight line _{HL of} less than 90 ° and is 45 ° to 90 °.
Also in this embodiment, the same effect as that of the first embodiment can be obtained.

In the present embodiment, as shown in FIG. 16, the angle α formed with the horizontal virtual straight line _HL of each first groove 72a of the first groove group 72 may be 0 ° or more. In this case, the angle β formed by the first groove group and the second groove group is 45 ° to 90 °.

  Although the golf club head and the golf club of the present invention have been described above, the present invention is not limited to the above-described embodiment, and various improvements or changes may be made without departing from the gist of the present invention. Of course.

Hereinafter, a golf club using the golf club head of the present invention will be specifically described.
In this example, for the golf clubs of Experimental Examples 1 to 36 shown in Tables 1 and 2 below, the flight distance of the hit ball (carry flight distance + roll flight distance total flight distance (m)) is an evaluation item. An evaluation test was conducted. The evaluation results are shown in Tables 1 and 2 below.
Moreover, the evaluation test of the flight distance of the hit ball was also performed on the reference example as a reference for evaluation.
Note that “* Note 1” in Table 2 below indicates that second grooves with an angle γ of 90 ° and second grooves with an angle γ of 85 ° are alternately arranged from the heel portion toward the toe portion. Is.
In “* Note 2” in Table 2 below, the second groove is gradually formed to a depth of 17.5 μm to 22.5 μm from the sole portion side to the upper portion, and further, from the sole portion side to the upper portion, 17. It shows that the width is gradually increased from 5 μm to 22.5 μm.
In addition, “* Note 3” in the following Table 2 indicates that the angle β can be expressed as angle γ−angle α, and the second groove having an angle γ of 90 ° and the second groove having an angle γ of 85 °. Are alternately arranged from the heel part toward the toe part side, indicating that there are two types of angles β of 90 ° and 85 °.

In this example, an evaluation test was performed using a golf club in which the same golf club shaft was attached to each golf club head. All loft angles were 48 °.
In this example, unless otherwise specified, TRX (trade name) balls manufactured by Yokohama Rubber Co., Ltd. were used as golf balls.
In the present embodiment, the width and depth of the first groove 32a and the second groove 34a are determined using a contact type surface roughness measuring instrument (for example, Mitutoyo Surf Test SJ-301). One groove 32a and one groove 32a were measured one by one in the long side of each groove or in the cross-sectional direction perpendicular to the virtual center line.

  Further, in this example, the golf club head shown in FIGS. 1 and 2 was used in Experimental Example 1, Experimental Examples 7-15, and Experimental Examples 26-29, 31, 32. In the golf club heads used in Experimental Example 1 and Experimental Examples 5 to 8, the length of the first groove 32a is 55 mm, the length of the first groove 32b is 48 mm, and the length of the first groove 32c is 41 mm. The length of the first groove 32d was 34 mm, the length of the first groove 32e was 27 mm, and the length of the first groove 32f was 20 mm. The total length of the first groove was 610 mm. Moreover, about the 2nd groove group, 16 2nd grooves were formed and each length was 30 mm. The total length of the second groove was 480 mm. In Experimental Example 1, the width of the first grooves 32a to 32f was 700 μm. The width of the second groove was 20 μm.

In Experimental Examples 7 to 9, the width of the first groove was 300, 450, and 600 μm, respectively.
In Experimental Examples 10 and 11, the depth of the first groove was 250 and 350 μm, respectively.
In Experimental Examples 12 and 13, the width of the second groove was 45 and 80 μm, respectively.
In Experimental Examples 14 and 15, the depth of the second groove was 35 and 45 μm, respectively.
In Experimental Examples 26 and 27, the width of the second groove was 3 and 110 μm, respectively.
In Experimental Examples 28 and 29, the depth of the second groove was 3, 60 μm, respectively.
In Experimental Example 31, the depth of the first groove was 180 μm.
In Experimental Example 32, the width of the first groove was 220 μm.

  Moreover, the golf clubs shown in FIG. 14 were used in Experimental Examples 2 to 4 and 25. About the 1st groove group, it is the same composition as example 1 of an experiment. In addition, as for the second groove group, the second grooves 70 are formed so as to extend obliquely from the heel side toward the toe side as they go upward from the sole portion, and only the angle β is different. Except for this, the configuration is the same as in Experimental Example 1. In Experimental Example 2, the angle β is 80 °, in Experimental Example 3, the angle β is 65 °, in Experimental Example 4, the angle β is 50 °, and in Experimental Example 25, the angle β is 40 °. °.

  In Experimental Examples 5, 6, and 30, golf clubs having the first groove group and the second groove group shown in FIG. 5 were used. About the 2nd groove group, it is the same composition as example 1 of an experiment. As for the first groove group, the first grooves are formed so as to extend obliquely from the heel side toward the toe side as they go upward from the sole portion, and only the angle α is different. Except for this, the configuration is the same as in Experimental Example 1. In Experimental Example 5, the angle α was 3 °, in Experimental Example 6, the angle α was 10 °, and in Experimental Example 30, the angle α was 20 °.

  In Experimental Example 16, the golf club head used in Experimental Example 1 and the same configuration except that the radius of curvature of the first groove group was 400 mm were used.

In Experimental Examples 17 to 19 and 33, golf club heads shown in FIGS. 1 and 2 were used. The golf club heads used in Experimental Examples 17 to 19 and 33 differ from Experimental Example 1 in the total length of the first groove, and the other configurations are the same as in Experimental Example 1.
In Experimental Examples 17 to 19 and 33, the total length of the first groove was 300, 430, 900, and 230 mm, respectively.

In Experimental Examples 20-22 and 34, the golf club head shown in FIGS. 1 and 2 was used. The golf club heads used in Experimental Examples 20 to 22 and 34 differ from Experimental Example 1 in the total length of the second grooves, and the other configurations are the same as in Experimental Example 1.
In Experimental Examples 20 to 22, and 34, the total length of the second groove was 130, 300, 800, and 90 mm, respectively.

In Experimental Example 23, the golf club head shown in FIGS. 1 and 2 was used. The golf club head used in Experimental Example 23 differs from Experimental Example 1 in the total length and interval of the first grooves, and the other configurations are the same as in Experimental Example 1.
In Experimental Example 23, the total length of the first grooves was 377 mm, and the interval was 4.5 mm.

In Experimental Example 24, the golf club head shown in FIGS. 1 and 2 was used. The golf club head used in Experimental Example 24 differs from Experimental Example 1 in the total length and interval of the second grooves, and the other configurations are the same as in Experimental Example 1.
In Experimental Example 24, the total length of the second grooves was 240 mm, and the interval was 6.5 mm.

  In Experimental Example 35, the golf club shown in FIG. 14 was used. About the 1st groove group, it is the same composition as example 1 of an experiment. Note that Experimental Example 35 is formed so that each of the second grooves of the second groove group extends obliquely from the heel side (hosel part side) to the toe side as it goes upward from the sole part. In Experimental Example 35, the second grooves having an angle β of 90 ° and the second grooves having an angle β of 85 ° were alternately arranged from the heel portion toward the toe portion. Further, 16 second grooves having a length of 30 mm were formed, and the total length of the second grooves was 480 mm. The interval between the second grooves was 1.7 mm.

In Experimental Example 36, the golf club head shown in FIGS. 1 and 2 was used. The golf club head used in Experimental Example 36 differs from Experimental Example 1 in the cross-sectional shape (depth and width) of the second groove, and the other configurations are the same as in Experimental Example 1.
Experimental Example 36 is formed so that the depth of the second groove gradually increases from 17.5 μm to 22.5 μm from the sole part side to the upper part, and the width further increases from 17.5 μm to the upper part from the sole part side to the upper part. It is formed so as to be gradually widened to 22.5 μm.

Further, as a reference example, a golf club head formed only with the first groove group was used. The first groove group in the reference example has the same configuration as the first groove group in Experimental Example 1.
In the experimental examples 1 to 36 and the reference example, except for the experimental examples 35 and 36, the cross-sectional shape does not change, but is a constant cross-sectional shape formed with a predetermined dimension.

About the flight distance of a hit ball, it targeted 20 golfers. Each person used the golf clubs of Experimental Examples 1 to 36 and the reference example to strike each golf club, and measured the flight distance of the hit ball. Next, for each golf club, the standard deviation of the flight distance of five balls was determined. Next, the average value of the standard deviation of the flying distance of each hit ball in each golf club obtained for 20 golfers was used as the final evaluation result (standard deviation 1 and standard deviation 2).
The conditions for hitting the golf ball were two types of turf lengths of 15 mm and 45 mm. In Table 1 below, the evaluation result when the turf length is 15 mm is shown as standard deviation 1, and the evaluation result when the turf length is 45 mm is shown as standard deviation 2.

The “ratio” shown in Table 1 below is a value obtained by standard deviation 2 / standard deviation 1. It was evaluated that a relatively stable flight distance can be obtained as the ratio is smaller, regardless of conditions.
Furthermore, the “index” shown in Tables 1 and 2 below is a value obtained by dividing the ratio of the reference example by the ratio of each experimental example and multiplying by 100. That is, the “index” indicates how much result is obtained for each experimental example with the reference example being 100. It was evaluated that as the numerical value of the “index” is larger, a relatively stable flight distance can be obtained without being influenced by the condition (turf condition).

As shown in Table 1 above, Experimental Examples 1 to 36 had a smaller ratio than the reference example, that is, a large index and a relatively stable flight distance.
Experimental Example 1 to Experimental Example 4 and 25 differ only in the angle β, Experimental Example 1 has an angle β of 90 °, Experimental Example 2 has an angle β of 80 °, Experimental Example 3 has an angle β of 65 °, In Experimental Example 4, the angle β was 50 °, and in Experimental Example 25, the angle β was 40 °.
Experimental example 4 is more preferable than experimental example 25, experimental example 3 is more preferable than experimental example 4, experimental example 2 is preferable to experimental example 3, experimental example 1 is preferable to experimental example 2 in angle β. Since the angle β is within a preferable range, the ratio was smaller than those of Experimental Examples 4 and 25, that is, the index was large and a relatively stable flight distance was obtained.
Further, in Experimental Example 25, the angle β was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental examples 1, 5, 6, and 30 are different only in the angle α, the experimental example 1 has an angle α of 0 °, the experimental example 5 has an angle α of 3 °, the experimental example 6 has an angle α of 10 °, In Experimental Example 30, the angle α was 20 °. Experimental example 6 is more preferable than experimental example 30, experimental example 5 is more preferable than experimental example 6, experimental example 1 is more preferable than experimental example 5, in the angle α, and experimental examples 1 and 5 are in the preferable range for the angle α. The ratio was smaller than Examples 6 and 30, that is, the index was large, and a relatively stable flight distance was obtained.
Furthermore, in Experimental Example 30, the angle α was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental examples 1, 7 to 9 and 32 differ only in the width of the first groove, experimental example 1 has a width of the first groove of 700 μm, experimental example 7 has a width of the first groove of 300 μm, In Experimental Example 8, the width of the first groove was 450 μm, in Experimental Example 9, the width of the first groove was 600 μm, and in Experimental Example 32, the width of the first groove was 220 μm.
Experimental example 7 is more preferable than experimental example 32, experimental example 8 is more preferable than experimental example 7, experimental example 9 is more preferable than experimental example 8, and experimental example 1 is more preferable than experimental example 9 in the width of the first groove. Since the width of the first groove was within a preferable range, the ratios of 1, 8, and 9 were smaller than those of Experimental Examples 7 and 32, that is, the index was large and a relatively stable flight distance was obtained.
Further, in Experimental Example 32, the width of the first groove was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental examples 1, 10, 11, and 31 differ only in the depth of the first groove, experimental example 1 has a depth of the first groove of 400 μm, and experimental example 10 has a depth of the first groove. 250 μm, Experimental Example 11 had a first groove depth of 350 μm, and Experimental Example 31 had a first groove depth of 180 μm.
Experimental example 10 is more preferable than experimental example 31, experimental example 11 is more preferable than experimental example 10, and experimental example 1 is more preferable than experimental example 11 in the depth of the first groove. Since the depth is in a preferable range, the ratio is smaller than those of Experimental Examples 10 and 31, that is, the index is large and a relatively stable flight distance is obtained.
Further, in Experimental Example 31, the depth of the first groove was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental Examples 1, 12, 13, 26, and 27 differ only in the width of the second groove, Experimental Example 1 has a width of the second groove of 20 μm, and Experimental Example 12 has a width of the second groove. In Experimental Example 13, the width of the second groove was 80 μm, in Experimental Example 26, the width of the second groove was 3 μm, and in Experimental Example 27, the width of the second groove was 110 μm.
Experimental example 13 is more preferable than experimental example 26, experimental example 12 is more preferable than experimental example 13, experimental example 1 is more preferable than experimental example 12, in the width of the second groove, and experimental example 12 is the width of the second groove. Is in a preferable range, and in Experimental Example 1, the width of the second groove is in a more preferable range. Of Experimental Examples 1, 12, 13, 26, and 27, Experimental Example 1 has the smallest ratio, then Experimental Example 12 has the smallest ratio, that is, Experimental Example 1 has the largest index, and then Experimental Example 12 The index was large and a relatively stable flight distance was obtained.
Further, in Experimental Examples 26 and 27, the width of the second groove was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental Examples 1, 14, 15, 28, and 29 differ only in the depth of the second groove, Experimental Example 1 has a second groove depth of 20 μm, and Experimental Example 14 has a second groove depth. The depth was 35 μm, Experimental Example 15 had a second groove depth of 45 μm, Experimental Example 28 had a second groove depth of 3 μm, and Experimental Example 29 had a second groove depth of 60 μm.
The experimental example 15 is more preferable than the experimental example 28, the experimental example 14 is more preferable than the experimental example 15, and the experimental example 1 is preferable to the experimental example 14 in the depth of the second groove. The depth is in a preferable range, and in Experimental Example 1, the depth of the second groove is in a more preferable range. Of Experimental Examples 1, 14, 15, 28, and 29, Experimental Example 1 has the smallest ratio, then Experimental Example 14 has the smallest ratio, that is, Experimental Example 1 has the highest index, and then Experimental Example 14 The index was large and a relatively stable flight distance was obtained.
Further, in Experimental Examples 28 and 29, the depth of the second groove was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

  Experimental examples 1 and 16 differ only in the radius of curvature of the first groove, experimental example 1 is a straight line, and experimental example 16 has a radius of curvature of 400 mm. In Experimental Example 1 in which the first groove group is configured in a straight line rather than Experimental Example 16, since the numerical value of the radius of curvature is in a more preferable range, the ratio is small, that is, the index is large and the flight is relatively stable. The distance was obtained.

Experimental examples 1, 17, 18, 19, and 33 differ only in the total length of the first groove. Experimental example 1 has a total length of the first groove of 610 mm, and experimental example 17 has a total length of the first groove. 300 mm, Experimental Example 18 had a total length of the first groove of 430 mm, Experimental Example 19 had a total length of the first groove of 900 mm, and Experimental Example 33 had a total length of the first groove of 230 mm.
Experimental Example 17 is more preferable than Experimental Example 33, Experimental Example 18 is more preferable than Experimental Example 17, Experimental Example 1 is preferable to Experimental Example 18, and Experimental Example 19 is preferable to Experimental Example 1 in terms of the total length of the first groove. 1, 18 and 19 have a preferable total length of the first groove. Of Experimental Examples 1, 17, 18, 19, and 33, Experimental Example 19 has the smallest ratio, and then, Experimental Example 1 and Experimental Example 18 have the smallest ratio, that is, Experimental Example 19 has the largest index, Subsequently, the index was large in the order of Experimental Example 1 and Experimental Example 18, and a relatively stable flight distance was obtained.
Further, in Experimental Example 33, the total length of the first grooves was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

Experimental examples 1, 20, 21, 22, and 34 differ only in the total length of the second groove, experimental example 1 has a total length of the second groove of 480 mm, and experimental example 20 has a total length of the second groove. 130 mm, Experimental Example 21 had a total length of the second groove of 300 mm, Experimental Example 22 had a total length of the second groove of 800 mm, and Experimental Example 34 had a total length of the first groove of 90 mm.
Experimental example 20 is more preferable than Experimental example 34, Experimental example 21 is more preferable than Experimental example 20, Experimental example 1 is preferable to Experimental example 21, and Experimental example 22 is preferable to Experimental example 1 in terms of the total length of the second groove. 1, 2, 22 are within the preferable range of the total length of the second groove. Of Experimental Examples 1, 20, 21, 22, and 34, Experimental Example 22 has the smallest ratio, then Experimental Example 1 and Experimental Example 21 have the smallest ratio, that is, Experimental Example 1 has the largest index, Subsequently, the index was large in the order of Experimental Example 22 and Experimental Example 21, and a relatively stable flight distance was obtained.
Further, in Experimental Example 34, the total length of the second groove was out of the range of the present invention, and the ratio was large, that is, the index was small, and a relatively stable flight distance could not be obtained.

  Experimental examples 1 and 23 differ only in the total length and interval of the first grooves. In Experimental example 1, the total length of the first grooves is 610 mm and the interval is 2.8 mm. The total length of the first grooves was 377 mm and the interval was 4.5 mm. In Experimental Example 1, the total length and interval of the first grooves are in a preferable range than in Experimental Example 23, so the ratio is small, that is, the index is large, and a relatively stable flight distance is obtained.

  Experimental examples 1 and 24 differ only in the total length and interval of the second groove. Experimental example 1 has a total length of the second groove of 480 mm and an interval of 3.0 mm. The total length of the second grooves was 240 mm, and the interval was 6.5 mm. In Experimental Example 1, the total length and interval of the second grooves are in a preferable range than in Experimental Example 24, so the ratio was small, that is, the index was large, and a relatively stable flight distance was obtained.

  Experimental examples 1 and 35 differ only in the interval and angle γ of the second groove, and in experimental example 1, the total length of the second groove is 480 mm and the interval is 3.0 mm. In Experimental Example 35, second grooves having an angle γ of 90 ° and second grooves having an angle γ of 85 ° are alternately arranged from the heel portion toward the toe portion side. It was 1.7 mm. Since the distance between the second grooves and the angle γ are in the preferable ranges in Experimental Example 1 than in Experimental Example 35, the ratio is small, that is, the index is large, and a relatively stable flight distance is obtained.

  Experimental examples 1 and 36 differ only in the cross-sectional shape (depth and width) of the second groove, and in experimental example 1, the second groove has a depth of 20 μm and a width of 20 μm. In Experimental Example 36, the depth of the second groove is gradually increased from 17.5 μm to 22.5 μm from the sole side to the upper part, and further from 17.5 μm to 22.5 μm from the sole part side to the upper part. Widely formed. In Experimental Example 1, the depth and width of the first groove are constant, that is, since the cross-sectional shape is constant, the ratio is small, that is, the index is large and relatively stable. The flight distance was obtained.

Next, the effect of the center-of-gravity height _FGH of the golf club using the golf club head of the present invention will be specifically described.
In this example, for the golf clubs of Experimental Examples 40 and 41 shown in Table 3 below, an evaluation test was conducted with the hit distance (carry flight distance + roll flight distance (m)) as an evaluation item. went. The evaluation results are shown in Table 3 below.
In addition, with respect to the reference examples 10 and 11 as the reference for evaluation, an evaluation test of the hit distance of the hit ball was performed.

Also in this example, an evaluation test was conducted using a golf club in which the same golf club shaft was attached to each golf club head. All loft angles were 48 °.
In this example, unless otherwise specified, TRX (trade name) balls manufactured by Yokohama Rubber Co., Ltd. were used as golf balls.
Further, in this example, the width and depth of the first groove and the second groove are determined using a contact type surface roughness measuring machine (for example, Mitutoyo Surf Test SJ-301). Each groove of the groove and the second groove was measured one by one in the long side of each groove or in the cross-sectional direction perpendicular to the virtual center line.
In addition, about the evaluation test of the flight distance of a hit ball, it implemented similarly to the above-mentioned Example 1 (Experimental example 1 etc.). Further, in the same manner as in Example 1 (Experimental Example 1 and the like) described above, standard deviation 1 and standard deviation 2 were obtained, and “ratio” shown in Table 3 below was obtained. Evaluation based on the result of this ratio was performed in the same manner as in Example 1 (Experimental Example 1 and the like) described above.
Furthermore, the “index” shown in Table 3 below was also obtained in the same manner as in Example 1 (Experimental Example 1 and the like). Evaluation based on the result of this index was performed in the same manner as in Example 1 (Experimental Example 1 and the like) described above.

Reference example 10 shown in Table 3, as compared to the reference _example, except _{F GH} is 21.5 mm, the other configuration is the same configuration as the reference example.
Experimental Example 40 is different from the above Experimental Example _1, except _{F GH} is 21.5 mm, the other structure is the same structure as Experimental example 1.
Reference example 11, compared to the reference _example, except _{F GH} is 22.5 mm, the other configuration is the same configuration as the reference example.
Experimental Example 41 is different from the above Experimental Example _1, except _{F GH} is 22.5 mm, the other structure is the same structure as Experimental example 1.

As shown in Table _3, in _{F GH} is 21.5 mm, towards the Experimental Example 40 than the reference example 10 has a second groove is formed, the experimental example 40, the percentage than the reference example 10 Was small, that is, the index was large, and a relatively stable flight distance was obtained.
_In the _{F GH} is 22.5 mm, towards the Experimental Example 41 than the reference example 11 has a second groove is formed, the experimental example 41 has a smaller proportion than the reference example 11, i.e., index And a relatively stable flight distance was obtained.
Furthermore, the experimental example 40 (F _GH : 21.5 mm) and the reference example 10 (F _GH ) were compared to the difference in index between the experimental example 41 (F _GH : 22.5 mm) and the reference example 11 (F _GH : 22.5 mm). : 21.5 mm), and a relatively stable flight distance was obtained. Thus, in the present invention, a great effect was obtained particularly in a golf club having a relatively low center of gravity position where the center of gravity height _FGH is 22 mm or less.

Next, the effect of the loft angle of a golf club using the golf club head of the present invention will be specifically described.
In this example, for the golf clubs of Experimental Examples 50 and 51 shown in Table 4 below, an evaluation test was conducted with the hit distance (carry flight distance + roll flight distance (m)) as an evaluation item. went. The evaluation results are shown in Table 4 below.
Moreover, the evaluation example of the flight distance of the hit ball was also performed on the reference examples 20 and 21 as the evaluation reference.

Also in this example, an evaluation test was conducted using a golf club in which the same golf club shaft was attached to each golf club head.
In this example, unless otherwise specified, TRX (trade name) balls manufactured by Yokohama Rubber Co., Ltd. were used as golf balls.
Further, in this example, the width and depth of the first groove and the second groove are determined using a contact type surface roughness measuring machine (for example, Mitutoyo Surf Test SJ-301). Each groove of the groove and the second groove was measured one by one in the long side of each groove or in the cross-sectional direction perpendicular to the virtual center line.
In addition, about the evaluation test of the flight distance of a hit ball, it implemented similarly to the above-mentioned Example 1 (Experimental example 1 etc.). Further, in the same manner as in Example 1 (Experimental Example 1 and the like) described above, standard deviation 1 and standard deviation 2 were obtained, and “ratio” shown in Table 3 below was obtained. Evaluation based on the result of this ratio was performed in the same manner as in Example 1 (Experimental Example 1 and the like) described above.
Furthermore, the “index” shown in Table 3 below was also obtained in the same manner as in Example 1 (Experimental Example 1 and the like). Evaluation based on the result of this index was performed in the same manner as in Example 1 (Experimental Example 1 and the like) described above.

The reference example 20 shown in the following Table 4 is different from the reference example in that the loft angle is 46 °, and other configurations are the same as the reference example.
Experimental Example 50 is different from Experimental Example 1 in that the loft angle is 46 °, and the other configuration is the same as that of Experimental Example 1.
The reference example 21 is different from the reference example in that the loft angle is 44 °, and other configurations are the same as the reference example.
Experimental Example 51 is different from Experimental Example 1 in that the loft angle is 44 °, and the other configuration is the same as that of Experimental Example 1.

As shown in Table 4 above, when the loft angle is 46 °, the second groove is formed in the experimental example 50 than in the reference example 20, and the ratio of the experimental example 50 is higher than that of the reference example 20. Small, that is, a large index, a relatively stable flight distance was obtained.
When the loft angle is 44 °, the second groove is formed in the experimental example 51 compared to the reference example 21, and the ratio of the experimental example 51 is smaller than that of the reference example 21, that is, the index is higher. A large and relatively stable flight distance was obtained.
Furthermore, the difference in index between the experimental example 50 having a loft angle of 46 ° and the reference example 20 is larger than the difference in index between the experimental example 51 having a loft angle of 44 ° and the reference example 21, and a relatively stable flight distance is achieved. Obtained. Thus, in the present invention, a great effect was obtained particularly in a golf club having a loft angle of 45 ° or more.

1 is a schematic plan view showing a first embodiment of a golf club having a golf club head of the present invention. It is a principal part enlarged view of the golf club of 1st Embodiment shown in FIG. It is a schematic diagram showing the geometric relationship between the first groove group and the second groove group of the golf club head of the present invention. It is a typical perspective view showing composition of the 1st slot group and the 2nd slot group of the golf club head of the present invention. It is a typical front view showing a modification of the golf club of the first embodiment of the present invention. It is a mimetic diagram for explaining the center-of-gravity height and loft angle defined in the golf club head of the present invention. It is a schematic diagram for demonstrating the state which installs a golf club in an address position. It is a schematic diagram which shows the gravity center measuring device used in order to prescribe | regulate the gravity center height in this invention. (A) And (b) is a schematic diagram for demonstrating the measuring method using the gravity center measuring device when finding the point g in FIG. It is explanatory drawing explaining a part of measuring method when using a gravity center measuring device. It is explanatory drawing explaining the measurement of the loft angle of a golf club using the loft angle measuring device. It is the elements on larger scale of explanatory drawing shown in FIG. It is explanatory drawing explaining the measurement of the loft angle of a golf club using the loft angle measuring device shown in FIG. It is a typical top view showing a 2nd embodiment of a golf club which has a golf club head of the present invention. It is a principal part enlarged view of the golf club of 2nd Embodiment shown in FIG. It is a mimetic diagram showing the modification of the golf club which has the golf club head concerning a 2nd embodiment of the present invention.

Explanation of symbols

10, 10a Golf club 12, 12a Golf club head 14 Socket 16 Golf club shaft 18 Grip 20 Face portion 20a Face surface 22 Sole portion 24 Hosel portions 32, 36, 72 First groove groups 32a to 32f, 72a First groove 34, 70 Second groove group 34a, 70a Second groove H Horizontal plane _HL Horizontal imaginary line

Claims (7)

A golf club head having a face surface for hitting a golf ball, wherein the face surface is formed at a predetermined loft angle,
A first groove group in which a plurality of first grooves having a depth of 200 to 600 μm and a width of 250 to 1000 μm are formed on the face surface;
A second groove group in which a plurality of second grooves each having a depth of 5 to 50 μm and a width of 5 to 100 μm are formed on the face surface;
The first groove of the first groove group and the second groove of the second groove group are arranged so as to intersect with each other,
The total length of the first grooves of the first groove group is 250 to 1200 mm, and the total length of the second grooves of the second groove group is 100 to 1200 mm. Yes,
Furthermore, an angle α formed between the first groove of the first groove group and a horizontal imaginary line on the face surface is 0 ° to 15 °, and the second groove of the second groove group And the horizontal imaginary line has an angle β of 45 ° to 90 °.   2. The golf club head according to claim 1, wherein an interval between the first grooves in the first groove group is 1.5 to 4.0 mm.   3. The golf club head according to claim 1, wherein an interval between the second grooves in the second groove group is 1.0 to 6.0 mm.   The golf club head according to claim 1, wherein the first groove and the second groove have a radius of curvature of 500 mm or more. When the face surface is arranged on the horizontal plane so as to have the predetermined loft angle, the height of the center of gravity from the point where the perpendicular perpendicular to the face surface passing through the center of gravity of the golf club head intersects the face surface to the horizontal plane is F. The golf club head according to any one of claims 1 to 4, wherein the center-of-gravity height _FGH is 22 mm or less when _GH (mm) is used.   The golf club head according to claim 1, wherein the loft angle is 45 ° or more.   A golf club comprising the golf club head according to claim 1.

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