Golf Club Head

Abstract

To improve a carry of a hit ball.SOLUTION: A golf club head 1 having a hollow part in the inside includes a face portion 2 having a face 2a, a crown portion 3, and a sole portion 4. The face portion 2 includes a face inner surface 2i facing the hollow part i, and the crown portion 3 includes a crown inner surface 3i facing the hollow part i. In a vertical cross section of the head passing through a face center FC, (a) a ratio Hf / H of a height Hf of the face measured in a direction T of a tangent line drawn passing the face center FC to a maximum height H of the head measured in the direction T of the tangent line is 0.65 or less, (b) in measuring at a first boundary point B1 between the face inner surface 2i and the crown inner surface 3i, a radius of curvature is 4.0 to 10.0 mm, and (c) at the first boundary point B1, a wall thickness is 1.5 mm or more.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a golf club head. [Background technology]

[0002] Golfers have a desire to increase the distance of their shots. In order to increase the distance of their shots, it is important to improve the repulsion performance of the golf club head, for example. The following Patent Document 1 proposes a golf club head that can control the thickness distribution of the face portion to allow the face portion to bend significantly when hitting the ball, thereby improving the repulsion performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5583827 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to increase the flight distance of a hit ball, it is important to not only improve the repulsion performance of the golf club head, but also to reduce the amount of backspin on the hit ball. The inventors have found that by suppressing the bending of the face part when hitting the ball, while promoting the bending of the body part (crown part and / or sole part), the amount of backspin can be reduced, and thus the flight distance of the hit ball can be increased.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a golf club head capable of improving the flight distance of a hit ball. [Means for solving the problem]

[0006] A first aspect of the present invention is a golf club head having a hollow portion therein, the golf club head including a face portion having a face, a crown portion, and a sole portion, the face portion having a face inner surface facing the hollow portion, the crown portion having a crown inner surface facing the hollow portion, the face having a face center, and in a head longitudinal section passing through the face center, (a) a ratio Hf / H of a face height Hf measured in a tangent direction drawn to the face center to a maximum head height H measured in the tangent direction is 0.65 or less; (b) a radius of curvature at a first boundary point which is a boundary between the face inner surface and the crown inner surface is 4.0 to 10.0 mm; (c) A golf club head, wherein the thickness at the first boundary point is 1.5 mm or more.

[0007] In another aspect of the first invention, in a first region from the first boundary point to a first point that is 10 mm toward the crown, the crown portion may have a smallest thickness at the first point.

[0008] In another aspect of the first aspect of the invention, the thickness of the crown portion may decrease, rather than increase, from the first boundary point to the first point.

[0009] In another aspect of the first invention, the crown portion may have a thickness of 1.0 mm or less at the first point.

[0010] In another aspect of the first invention, the sole portion has a sole inner surface facing the hollow portion, (d) in the head longitudinal section, a radius of curvature at a second boundary point which is a boundary between the face inner surface and the sole inner surface is 3.0 to 10.0 mm; (e) The thickness at the second boundary point may be 1.5 mm or more.

[0011] In another aspect of the first invention, in a second region from the second boundary point to a second point that is 15 mm toward the sole side, the sole portion may have a smallest thickness at the second point.

[0012] In another aspect of the first invention, the thickness of the sole portion may decrease, rather than increase, from the second boundary point to the second point.

[0013] In another aspect of the first invention, the thickness of the sole portion at the second point may be 1.0 mm or less.

[0014] A second invention of the present application is a golf club head having a hollow portion therein, the golf club head including a face portion having a face, a crown portion, and a sole portion, the face portion having a face inner surface facing the hollow portion, the sole portion having a sole inner surface facing the hollow portion, the face having a face center, and in a head longitudinal section passing through the face center, (a) a ratio Hf / H of a face height Hf measured in a tangent direction drawn to the face center to a maximum head height H measured in the tangent direction is 0.65 or less; (d) in the head longitudinal section, a radius of curvature at a second boundary point which is a boundary between the face inner surface and the sole inner surface is 3.0 to 10.0 mm; (e) the wall thickness at the second boundary point is 1.5 mm or more; A golf club head.

[0015] In other aspects of the first and second aspects of the invention, the ratio Hf / H may be 0.50 or more. Effect of the Invention

[0016] The golf club head of the present invention, by adopting the above-mentioned configuration, can improve the flight distance of a hit ball. [Brief description of the drawings]

[0017] [Figure 1]1 is a perspective view of a golf club head according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a front view of the golf club head of the present embodiment. [Diagram 3] FIG. 2 is a plan view of the golf club head of the present embodiment. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 1A is a front view of a golf club head, and FIG. 1B is a cross-sectional view taken along line s1 of the golf club head. [Figure 6] FIG. 5 is an enlarged view of the portion VI-VI in FIG. [Figure 7] FIG. 4 is a contour diagram showing a deformation state near the face of the golf club head of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each embodiment, the same or common elements are given the same symbols, and duplicate explanations are omitted.

[0019] 1 to 3 are respectively a perspective view, a front view, and a plan view of a golf club head (hereinafter simply referred to as "head") 1 of this embodiment. In Figs. 1 to 3, the head 1 is placed in a standard state. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3.

[0020] [Reference condition] In this specification, the "reference state" of the head 1 refers to a state in which the head 1 is placed on a horizontal plane HP at a lie angle α (FIG. 2) and a loft angle (not shown) set for the head 1. As shown in FIG. 3, in the reference state, the head 1 is maintained at the lie angle α and the loft angle with the shaft axis center line CL of the head 1 being disposed within a reference vertical plane VP perpendicular to the horizontal plane HP. In this specification, unless otherwise specified, the head 1 is in the reference state.

[0021] The “shaft axial center line CL” is defined by the axial center line of a shaft insertion hole 5a formed in the hosel portion 5 of the head 1.

[0022] [Head Orientation] As shown in Figure 3, in the reference state of the head 1, the direction x perpendicular to the reference vertical plane VP is defined as the head front-rear direction. With respect to the head front-rear direction, the side of the face 2a is defined as the front side, and the opposite side is defined as the rear side. Moreover, the direction y parallel to both the reference vertical plane VP and the horizontal plane HP is defined as the toe-heel direction. Furthermore, the direction z perpendicular to the horizontal plane HP is defined as the head up-down direction.

[0023] [Basic head structure] The head 1 of this embodiment is a golf club head having a hollow portion i provided therein. Examples of this type of head include wood, hybrid, and iron types. In this embodiment, a wood type head 1 made of a metal material is shown as an example.

[0024] As shown in FIGS. 1 to 4, the head includes, for example, a face portion 2, a crown portion 3, and a sole portion 4.

[0025] The face portion 2 includes a face 2a which is a surface for hitting a ball, and a face inner surface 2i which faces the hollow portion i, as shown in Fig. 4. The face 2a has a bulge and a roll, and is thus configured as a three-dimensional curved surface that is convex toward the outside.

[0026] Although not particularly limited, the maximum thickness of the face portion 2 is, for example, 3.80 mm or less, preferably 3.70 mm or less, and more preferably 3.60 mm or less, from the viewpoint of maintaining high resilience performance. Similarly, the maximum thickness of the face portion 2 is, for example, 3.10 mm or more, preferably 3.20 mm or more, and more preferably 3.30 mm or more, from the viewpoint of maintaining durability.

[0027] Furthermore, the face 2a has a sweet spot SS and a face center FC.

[0028] In this specification, the "sweet spot SS" is the intersection point between the face 2a and a normal line N erected from the head center of gravity CG to the face 2a, as shown in Figure 1. The sweet spot SS is a hitting point where high repulsion can be expected.

[0029] The face 2a is defined by its periphery E. In this specification, the periphery E of the face 2a is defined as follows. First, as shown in FIG. 5(A), each cross section s1, s2, s3... including a normal line N connecting the head center of gravity G and the sweet spot SS is specified. Then, as shown in FIG. 5(B), a position Pe is obtained at each of the cross sections s1, s2, s3... where the radius of curvature r of the contour line Lf on the outer surface side of the head first becomes 200 mm from the sweet spot SS side toward the outside of the face, and the connection of these positions Pe is defined as the periphery E of the face 2a.

[0030] In this specification, "radius of curvature" is measured on the curve of interest. The radius of curvature of any point on a curve is determined as the radius of a single circle that passes through that point, a point 1 mm to one side of that point, and a point 1 mm to the other side of that point. These "1 mm" are the distance along the curve.

[0031] In this specification, the "face center" FC is determined as follows. First, an arbitrary point P is selected in the vicinity of the approximate center of the face 2a in the up-down direction and the toe-heel direction. Next, a plane is determined that passes through this point P, extends along the normal direction of the face 2a at the point P, and is parallel to the toe-heel direction. A line of intersection between this plane and the face 2a is drawn, and its midpoint Px is determined. Next, a plane is determined that passes through this midpoint Px, extends along the normal direction of the face 2a at the point Px, and is parallel to the up-down direction. A line of intersection between this plane and the face surface is drawn, and its midpoint Py is determined. Next, a plane is determined that passes through this midpoint Py, extends along the normal direction of the face 2a at the point Py, and is parallel to the toe-heel direction. A line of intersection between this plane and the face 2a is drawn, and its midpoint Px is newly determined. Next, a plane is determined that passes through the new midpoint Px, extends along the normal direction of the face 2a at the new midpoint Px, and is parallel to the up-down direction. A line of intersection between this plane and the face 2a is drawn, and its midpoint Py is determined anew. This process is repeated to determine Px and Py in sequence. In the repetition of this process, the new position Py (last position Py) at which the distance between the new midpoint Py and the previous midpoint Py becomes 0.5 mm or less for the first time is determined as the face center.

[0032] The face 2a is provided with a plurality of grooves called face lines extending in the toe-heel direction, but these are omitted from the drawings of this embodiment.

[0033] The crown portion 3 extends from the face portion 2 toward the rear of the head so as to form the top surface of the head. A hosel portion 5 is provided on the heel side of the crown portion 3. A shaft insertion hole 5a for fixing a club shaft (not shown) is formed in the hosel portion 5. The crown portion 3 has a crown inner surface 3i facing the hollow portion i.

[0034] The sole portion 4 extends from the face portion 2 toward the rear of the head so as to form the bottom surface of the head. The sole portion 4 is, for example, a portion that is visible in a bottom view of the head.

[0035] The main part of the head 1 is made of, for example, a metal material. The metal material is not particularly limited, but may be, for example, pure titanium, titanium alloy, stainless steel, maraging steel, aluminum alloy, magnesium alloy, tungsten-nickel alloy, etc. A part of the head 1 (for example, the crown portion 3) may be made of a non-metallic material such as fiber reinforced resin. The head 1 of this embodiment is formed of, for example, a titanium alloy.

[0036] Next, the head 1 has the following features (a) to (c) as a first embodiment, and the head 1 has the following features (a), (d) and (e) as a second embodiment.

[0037] [Feature (a)] Fig. 4 is a head longitudinal section passing through the face center FC. This head longitudinal section is a section perpendicular to the horizontal plane HP, like the IV-IV plane in Fig. 2. The characteristic (a) is that the ratio Hf / H of the height Hf of the face 2a measured in the tangent direction T drawn to the face center FC in the head longitudinal section to the maximum head height H measured in the tangent direction T is 0.65 or less. Here, the height Hf of the face 2a is the distance in the tangent direction T between the upper and lower peripheries E, E of the face 2a in the head longitudinal section.

[0038] [Feature (b)] Fig. 6 shows an enlarged view of the VI-VI portion of Fig. 4. As shown in Fig. 6, the feature (b) is that the radius of curvature R1 at a first boundary point B1, which is the boundary between the face inner surface 2i and the crown inner surface 3i, in the head longitudinal section is 4.0 to 10.0 mm. Here, the first boundary point B1 is a point where the radius of curvature of the contour line of the head inner surface is minimum in the vicinity of the boundary between the face inner surface 2i and the crown inner surface 3i. When the part where the radius of curvature is minimum is a curve (arc) rather than a point, the midpoint of the curve is the first boundary point B1.

[0039] [Feature (c)] The characteristic (c) is that the thickness t1 at the first boundary point B1 is 1.5 mm or more.

[0040] [Feature (d)] Feature (d) is that the radius of curvature R2 at the second boundary point B2, which is the boundary between the face inner surface 2i and the sole inner surface 4i, in the head longitudinal section is 3.0 to 10.0 mm. Here, the second boundary point B2 is a point where the radius of curvature of the contour line of the head inner surface is minimum in the vicinity of the boundary between the face inner surface 2i and the sole inner surface 4i. If the part where the radius of curvature is minimum is a curve (arc) rather than a point, the midpoint of the curve is the second boundary point B2.

[0041] [Feature (e)] The characteristic (e) is that the thickness t2 at the second boundary point B2 is 1.5 mm or more.

[0042] [Operation of this embodiment] A detailed study of the deformation of conventional golf club heads when hitting a ball revealed that the boundary between the face and body (i.e., the crown and / or sole) is the starting point of bending, and only the face bends, with the body barely bending at all. Such head bending tends to increase the amount of backspin on a hit ball. In order to improve the head bending so as to reduce the amount of backspin on a hit ball, the inventor adopted the above features (a) to (c) in the first embodiment, and the above features (a), (d) and (e) in the second embodiment.

[0043] That is, in the first and second embodiments, due to the feature (a), the face 2a of the head 1 is relatively small with respect to the maximum head height H. Therefore, in such a head 1, the deflection of the face 2a during hitting of the ball is kept small.

[0044] In the first embodiment, as in features (b) and (c), the first boundary point B1 between the face inner surface 2i and the crown inner surface 3i is formed with a specific radius of curvature R1 and thickness t1, thereby preventing the vicinity of the first boundary point B1 from becoming the starting point of bending when hitting a ball. Therefore, the impact force received by the face 2a is effectively transmitted to the crown portion 3, and the deflection of the crown portion 3 can be increased.

[0045] Similarly, in the second embodiment, as in features (d) and (e), the second boundary point B2, which is the boundary between the face inner surface 2i and the sole inner surface 4i, is formed with a specific radius of curvature R2 and thickness t2, thereby preventing the vicinity of the second boundary point B2 from becoming the starting point of bending when hitting a ball. Therefore, the impact force received by the face 2a is effectively transmitted to the sole portion 4, and the deflection of the sole portion 4 can be increased.

[0046] As described above, in the head 1 of each embodiment, when hitting a ball, the bending of the face portion 2 is suppressed, while the bending of the body portion side is promoted, resulting in a large bending. Such bending characteristics of the head 1 can increase the contact area between the face 2a and the ball compared to the past, while maintaining high repulsion performance of the head 1. When the contact area between the face 2a and the ball is increased, the amount of backspin of the hit ball is reduced due to the recoil effect, and the flight distance of the hit ball is increased.

[0047] In a more preferable third embodiment, the head 1 may have all of the features (a), (b), (c), (d) and (e). This prevents the first boundary point B1 and the second boundary point B2 from bending significantly when hitting the ball, and the impact force received by the face 2a is effectively transmitted to both the crown portion 3 and the sole portion 4, thereby increasing the bending there. Therefore, in the third embodiment, the flight distance can be further increased.

[0048] In the present invention, it is sufficient that the head vertical section passing through the face center FC satisfies the above-mentioned characteristics, but it is preferable that at least one of the characteristics (a) to (e), more preferably two or more, and even more preferably all of the characteristics are formed over a range S in the toe-heel direction centered on the face center FC as shown in Fig. 2. This is desirable because the above-mentioned action can be obtained over a wider range of the face 2a in the toe-heel direction. The range S is, for example, 10 mm or more, preferably 15 mm or more, and even more preferably 20 mm or more.

[0049] [Preferable Hf / H ratio] The ratio Hf / H of the characteristic (a) may be preferably 0.63 or less, more preferably 0.61 or less. This is desirable in that the deflection of the face 2a when hitting the ball is further suppressed. On the other hand, in consideration of the directionality of the hit ball, a certain level of height Hf of the face 2a is desired, so the ratio Hf / H may be, for example, 0.50 or more, more preferably 0.51 or more, and even more preferably 0.53 or more.

[0050] [Preferable aspects of thicknesses t1 and t2] In order to more effectively exert the above-mentioned action, the thickness t1 at the first boundary point B1 and the thickness t2 at the second boundary point B2 may be more preferably 1.8 mm or more, and even more preferably 2.0 mm or more. On the other hand, in order to suppress a decrease in the repulsion performance of the head 1, the thickness t1 at the first boundary point B1 and the thickness t2 at the second boundary point B2 may be, for example, 4.0 mm or less, preferably 3.6 mm or less, and more preferably 3.3 mm or less.

[0051] [Preferable embodiment of the crown part] In order to allow the crown portion 3 side to bend more when hitting a ball, in a first region A1 from the first boundary point B1 to a first point P1, which is 10 mm toward the crown side (head rear side), the crown portion 3 has the smallest thickness at the first point P1. This further suppresses bending at the first boundary point B1 when hitting a ball, while increasing the bending of the crown portion 3 further rearward of the head. Here, the "10 mm" is the distance along the contour line of the inner surface of the head.

[0052] It is desirable that the thickness of the crown portion 3 decreases without increasing from the first boundary point B1 to the first point P1. In other words, it is desirable that the thickness of the crown portion 3 in the first region A1 decreases continuously toward the first point P1, or that the crown portion 3 may have a constant thickness portion but does not increase in thickness toward the first point P1. This further suppresses bending at the first boundary point B1 when hitting the ball, and further enhances the effect of increasing the deflection of the crown portion 3.

[0053] At the first point P1, the thickness t10 of the crown portion 3 is desirably set to, for example, 1.0 mm or less. By thinning the first point P1 in this manner, the deflection of the crown portion 3 when hitting the ball can be shifted toward the first point P1 from the first boundary point B1, and bending at the first boundary point B1 can be more reliably suppressed. From the viewpoint of maintaining the durability of the crown portion 3, the thickness t10 is set to, for example, 0.4 mm or more, preferably 0.6 mm or more.

[0054] [Preferable embodiment of sole part] In order to allow the sole portion 4 side to bend more when hitting the ball, in the second region A2 from the second boundary point B2 to the second point P2, which is 15 mm toward the crown (head rear side), the sole portion 4 has the smallest thickness at the second point P2. This further suppresses bending at the second boundary point B2 when hitting the ball, while increasing the bending of the sole portion 4 further rearward of the head. Here, the "15 mm" refers to the distance along the contour line of the inner surface of the head.

[0055] It is desirable that the thickness of the sole portion 4 decreases without increasing from the second boundary point B2 to the second point P2. In other words, it is desirable that the thickness of the sole portion 4 in the second region A2 decreases continuously toward the second point P2, or that the sole portion 4 may have a constant thickness portion but does not increase in thickness toward the second point P2. This further suppresses bending at the second boundary point B2 when hitting the ball, and further enhances the effect of increasing the deflection of the sole portion 4.

[0056] At the second point P2, the thickness t20 of the sole portion 4 is desirably 1.0 mm or less. By thinning the second point P2 in this manner, the deflection of the sole portion 4 when hitting the ball can be shifted toward the second point P2 from the second boundary point B2, and bending at the second boundary point B2 can be more reliably suppressed. From the viewpoint of maintaining the durability of the sole portion 4, the thickness t20 is, for example, 0.4 mm or more, preferably 0.6 mm or more.

[0057] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above specific disclosure, and can be implemented in various modified forms within the scope of the technical ideas described in the claims. EXAMPLES

[0058] Golf club heads (embodiments) having the basic structure shown in Figures 1 to 4 were prototyped based on the specifications in Table 1, and tests were conducted on the flying distance, backspin amount, and durability of the prototypes. For comparison, similar tests were also conducted on golf club heads (comparative examples) not according to the present invention.

[0059] The golf club heads of the examples and comparative examples were both made of titanium alloy produced by lost wax precision casting, had a head volume of 460cc, a head weight of 200g, and a loft angle of 9.5 degrees, and were essentially the same except for the specifications shown in Table 1. The test method was as follows.

[0060] <Ball speed, distance, and amount of backspin> A shaft and a grip were attached to each head to make a club, which was then attached to a swing robot. The impact point was set at the face center, and five hits were made with a head speed of 50 m / s, and the average launch speed (initial speed), flight distance (total flight distance including run), and backspin amount of the hit ball were calculated. The results are expressed as an index with the flight distance and backspin amount of Comparative Example 1 set at 100.

[0061] <Durability> A shaft and grip were attached to each head to make a club, and this was then attached to a swing robot. The club was hit up to 6,000 times with a head speed of 50 m / s, with the impact point at the face center, and the number of hits at which the head broke was recorded. If the head did not break after 6,000 hits, "OK" was displayed, and if the head broke after less than 5,000 hits, the number of hits at which it broke was displayed.

[0062] The test results are shown in Table 1. [Table 1]

[0063] As a result of the test, it was confirmed that the heads of the examples had a lower amount of backspin on the ball and an increased flight distance compared to the comparative examples.

[0064] Next, the deformation state of the heads of Example 1 and Comparative Example 1 was confirmed by simulation. An FEM model of each head was created, and a simulation was performed in which a ball was collided with the heads by setting the material properties of each member. The position where the ball impacted was the face center, and the impact speed was 48.87 m / s. FIG. 7 shows the results of this simulation. To clarify the difference in deformation of the heads, the cross section of Example 1 (solid line) and the cross section of Comparative Example 1 (dashed line) are superimposed in FIG. 7, and the deformation magnification is set to 20 times.

[0065] As is clear from FIG. 7, in Example 1, compared to Comparative Example 1, the bending originates on the body side, the bending spreads to the crown and sole portions, and a large bending occurs toward the outside of the head. [Explanation of symbols]

[0066] 1 Head 2 Face section 2a Face 2i Face inner surface 3 Crown 3i Crown inner surface 4 Sole 4i Sole inner surface i Hollow part FC Face Center Hf Face height H Maximum head height B1 1st boundary point P1 1st Point A1 1st area B2 2nd boundary point P2 2nd point A2 2nd area T Tangential direction

Claims

1. A golf club head having a hollow portion therein, The golf club includes a face portion having a face, a crown portion, and a sole portion, the face portion has a face inner surface facing the hollow portion, The crown portion has an inner crown surface facing the hollow portion, the face has a face center; In a head longitudinal section passing through the face center, (a) a ratio Hf / H of a face height Hf measured in a tangent direction drawn to the face center to a maximum head height H measured in the tangential direction is 0.65 or less; (b) the face inner surface and the crown inner surface are connected by a smooth arc, and a radius of curvature at a first boundary point which is a boundary between the face inner surface and the crown inner surface is 4.0 to 10.0 mm; (c) the wall thickness at the first boundary point is 1.5 to 4.0 mm; In a first region from the first boundary point to a first point that is 10 mm toward the crown side, the crown portion has a smallest wall thickness at the first point, The thickness of the crown portion decreases without increasing from the first boundary point to the first point, At the first point, the thickness of the crown portion is 0.4 to 1.0 mm. Golf club head.

2. The sole portion has an inner sole surface facing the hollow portion, (d) in the longitudinal section of the head, a radius of curvature at a second boundary point which is a boundary between the face inner surface and the sole inner surface is 3.0 to 10.0 mm; (e) the wall thickness at the second boundary point is 0.4 to 1.5 mm; The golf club head of claim 1 .

3. A golf club head as described in claim 2, wherein in a second region from the second boundary point to a second point 15 mm toward the sole, the sole portion has the smallest thickness at the second point.

4. A golf club head as described in claim 3, wherein the thickness of the sole portion decreases without increasing from the second boundary point to the second point.

5. A golf club head as described in claim 3 or 4, wherein at the second point, the thickness of the sole portion is 0.4 to 1.0 mm.

6. A golf club head having a hollow portion therein, The golf club includes a face portion having a face, a crown portion, and a sole portion, the face portion has a face inner surface facing the hollow portion, The sole portion has a sole inner surface facing the hollow portion, the face has a face center; In a head longitudinal section passing through the face center, (a) a ratio Hf / H of a face height Hf measured in a tangent direction drawn to the face center to a maximum head height H measured in the tangential direction is 0.65 or less; (d) in the longitudinal section of the head, a radius of curvature at a second boundary point which is a boundary between the face inner surface and the sole inner surface is 3.0 to 10.0 mm; (e) the wall thickness at the second boundary point is 1.5 to 4.0 mm; In a second region from the second boundary point to a second point that is 15 mm toward the sole side, the sole portion has a smallest thickness at the second point, The thickness of the sole portion decreases without increasing from the second boundary point to the second point, At the second point, the thickness of the sole portion is 0.4 to 1.0 mm. Golf club head.

7. A golf club head as described in any one of claims 1 to 6, wherein the ratio Hf / H is 0.50 or greater.

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