Golf club head

Abstract

To provide a golf club head that can be swung by a user easily.SOLUTION: A golf club head of the present invention is a golf club head of 400-460 cc in cubic volume, and includes a face part with a face surface, which serves as a hitting surface, and a body part formed of carbon. The body part includes a sole part with a weight member on its inner surface side and a crown part. The weight member includes a first weight member disposed directly below the gravity center of the golf club head, and a second weight member extending in a toe-heel direction from the first weight member.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] In recent years, the volume of golf club heads has been increasing. A golf club head with a large volume gives users a visual sense of security. However, a weight member may be arranged at a position away from the center of gravity of the golf club head. In such a case, users may feel that the golf club head is difficult to swing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a golf club head that is easy for a user to swing.

Means for Solving the Problems

[0005] The present golf club head is a golf club head having a volume of 400 cc or more and 460 cc or less, and includes a face portion having a face surface serving as a striking surface and a body portion formed of carbon. The body portion includes a sole portion and a crown portion. A weight member is provided on the inner surface side of the sole portion. The weight member includes a first weight member disposed directly below the center of gravity of the golf club head and a second weight member extending from the first weight member in the toe-heel direction. The first weight member is positioned so that its bottom surface is in contact with the inner surface of the sole, and the second weight member is positioned along the inner surface of the sole, and in plan view, the second weight member is crescent-shaped. .

Effects of the Invention

[0006] According to the disclosed technology, it is possible to provide a golf club head that is easy for the user to swing. [Brief explanation of the drawing]

[0007] [Figure 1] This is a perspective view illustrating a golf club head 1 according to the first embodiment. [Figure 2] This is a plan view illustrating a golf club head 1 according to the first embodiment. [Figure 3] This is a bottom view illustrating a golf club head 1 according to the first embodiment. [Figure 4] This is a cross-sectional view illustrating a golf club head 1 according to the first embodiment. [Figure 5] This is a diagram illustrating the weight member 70. [Figure 6] This diagram illustrates how the weight member 70 is embedded between the layers of the fiber-reinforced resin sheet. [Figure 7] This is a perspective view illustrating a golf club head 1A according to a modified example 1 of the first embodiment. [Figure 8] This is a plan view illustrating a golf club head 1A according to a modified example 1 of the first embodiment. [Figure 9] This is a cross-sectional view illustrating a golf club head 1A according to a modified example 1 of the first embodiment. [Figure 10] This is a plan view illustrating the sole portion of a golf club head 1A according to a modified example 1 of the first embodiment. [Figure 11] This figure shows an example of a method for fastening the weight member 70. [Modes for carrying out the invention]

[0008] The embodiments will be described below with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] <First Embodiment> FIG. 1 is a perspective view illustrating a golf club head 1 according to the first embodiment. FIG. 2 is a plan view illustrating the golf club head 1 according to the first embodiment. FIG. 3 is a bottom view illustrating the golf club head 1 according to the first embodiment. FIG. 4 is a cross-sectional view illustrating the golf club head 1 according to the first embodiment. Note that FIG. 4 shows a cross-section taken along a plane that passes through the center of gravity G of the golf club head 1, is perpendicular to the horizontal plane H (corresponding to the ground), and faces the toe-heel direction when the golf club head 1 is grounded at the reference lie angle and the reference loft angle with respect to the horizontal plane H.

[0010] In FIGS. 1 to 4, arrow d1 indicates the toe-heel direction (left-right direction), arrow d2 indicates the crown-sole direction (up-down direction), and arrow d3 indicates the face-back direction (front-back direction). Note that in subsequent figures, the same directions may be indicated.

[0011] The golf club head 1 shown in FIGS. 1 to 4 is a wood-type golf club head, for example, a driver. The golf club head 1 includes a face portion 10 and a body portion 20, and is a hollow structure in which the face portion 10 and the body portion 20 are joined and integrated. The volume of the golf club head 1 is 400 cc or more and 460 cc or less.

[0012] The body portion 20 has an opening that opens to the face side. A step for positioning the face portion 10 is provided on the outer peripheral portion of the opening of the body portion 20, and the face portion 10 is joined to the body portion 20 so as to fit into the step and close the opening. Note that the inner surface of the hollow structure may be referred to as the inner surface, and the outer surface may be referred to as the outer surface.

[0013] The face portion 10 is a portion provided with a face surface 10f that serves as a striking surface. Note that the face portion 10 has a predetermined thickness, and the face surface 10f forms the outer surface of the face portion 10. The face portion 10 can be formed using, for example, titanium, a titanium alloy, stainless steel, aluminum, an aluminum alloy, an iron-based metal, magnesium, a magnesium alloy, or the like.

[0014] The face portion 10 may be formed using a fiber-reinforced resin. Here, the fiber-reinforced resin is a composite material of fibers serving as reinforcing members and a resin. Examples of the fibers constituting the fiber-reinforced resin include carbon fibers, glass fibers, aramid fibers, polyethylene fibers, zylon fibers, boron fibers, and the like. Examples of the resin constituting the fiber-reinforced resin include epoxy resins, phenolic resins, polyester resins, polycarbonate resins, and the like. The face portion 10 can be formed using, for example, a carbon fiber-reinforced resin.

[0015] The body portion 20 includes a crown portion 21 and a sole portion 22. The body portion 20 may further include a hosel housing portion 23. The crown portion 21 is a portion that forms the upper part of the golf club head 1. The sole portion 22 is a portion that forms the bottom part of the golf club head 1. The hosel housing portion 23 is a portion that houses a hosel connected to a shaft.

[0016] The body portion 20 is formed of carbon. The body portion 20 can be formed, for example, by laminating and molding carbon fiber-reinforced resin sheets. The crown portion 21, the sole portion 22, and the hosel housing portion 23 may be integrally formed by laminating carbon fiber-reinforced resin sheets.

[0017] The golf club head 1 includes a weight member 70 on the inner surface side of the sole portion 22. The weight member 70 is located slightly on the heel side from the substantially central portion in the toe-heel direction and on the face portion 10 side in the face-back direction. The weight member 70 is formed, for example, such that the weight on the toe side and the weight on the heel side are substantially equal. Note that the weight member 70 cannot be visually recognized from the outside of the golf club head 1.

[0018] Figure 5 is a diagram illustrating the weight member 70. Figure 5(a) is a view of the weight member 70 from the crown portion 21 side, and Figure 5(b) is a view of the weight member 70 from the sole portion 22 side. Figure 5(c) shows a cross-section of the golf club head 1 when it is placed on the horizontal plane H in the same manner as in Figure 4, according to the standard lie angle and standard loft angle, and is cut by a plane that passes through the center of gravity G of the golf club head 1, is perpendicular to the horizontal plane H, and faces in the face-back direction.

[0019] As shown in Figure 5, the weight member 70 includes a first weight member 71 and a second weight member 72. In other words, the first weight member 71 and the second weight member 72 are combined to form the weight member 70. The first weight member 71 is located near the center of the weight member 70 in the longitudinal direction in a plan view. A plan view is a view from the crown portion 21 side in a direction perpendicular to the horizontal plane H. The second weight member 72 extends from the first weight member 71 in the toe-heel direction in a plan view.

[0020] The first weight member 71 is positioned directly below the center of gravity G of the golf club head 1. Here, "directly below the center of gravity G" means that when the golf club head 1 is placed on the horizontal plane H in accordance with the standard lie angle and standard loft angle as shown in Figure 4, a line passing through the center of gravity G and perpendicular to the horizontal plane H intersects with any part of the first weight member 71.

[0021] The first weight member 71 is, for example, frustoconical in shape, and is positioned so that its base contacts the inner surface of the sole portion 22. When the first weight member 71 is frustoconical, for example, the diameter of the top surface is 8 mm to 16 mm, the diameter of the base surface is 18 mm to 26 mm, and the height is 7 mm to 15 mm. Preferably, the diameter of the top surface is 9 mm to 15 mm, the diameter of the base surface is 19 mm to 25 mm, and the height is 8 mm to 14 mm. More preferably, the diameter of the top surface is 10 mm to 14 mm, the diameter of the base surface is 20 mm to 24 mm, and the height is 9 mm to 13 mm. By making the first weight member 71 frustoconical, the center of gravity of the golf club head 1 can be lowered. Note that the first weight member 71 is not limited to frustoconical shape, but may be cylindrical or frustoconical.

[0022] The second weight member 72 is a thinner, elongated member than the first weight member 71. The second weight member 72 is positioned along the inner surface of the sole portion 22. The width of the second weight member 72 (length in the face-back direction in a plan view) may be constant, but it is preferable that the center in the longitudinal direction is the widest and the width gradually decreases toward both ends in the longitudinal direction. In this way, the weight of the second weight member 72 becomes lighter as it moves away from the first weight member 71, thereby suppressing the change in the position of the center of gravity G due to the presence of the weight member 70.

[0023] In plan view, the second weight member 72 can be, for example, crescent-shaped. Here, a crescent shape is a closed shape in plan view in which both ends of a first curve having a predetermined radius of curvature are connected to both ends of a second curve that curves in the same direction as the first curve and has a larger radius of curvature than the first curve. In plan view, the second weight member 72 is positioned so that the convex side of the crescent shape faces the face portion 10. The radius of curvature of the first curve is, for example, 50 mm or more and 100 mm or less, and the radius of curvature of the second curve is, for example, 200 mm or more and 250 mm or less.

[0024] The second weight member 72 serves to reinforce the sole portion 22 as a rib, and the reinforcing effect as a rib can be enhanced by setting the radius of curvature of the first curve to 100 mm or less and the radius of curvature of the second curve to 250 mm or less. On the other hand, the smaller the radius of curvature of the first and second curves, the greater the reinforcing effect as a rib, but the center of gravity of the golf club head 1 will shift to the rear. By setting the radius of curvature of the first curve to 50 mm or more and the radius of curvature of the second curve to 200 mm or more, the reinforcing effect as a rib can be enhanced while suppressing the shift of the center of gravity of the golf club head 1 to the rear. Note that the first and second curves do not need to be perfect arcs; they just need to be curved.

[0025] As shown in Figure 4, the sole portion 22 is curved convexly toward the horizontal line H. Therefore, if the second weight member 72 is not crescent-shaped but an elongated rectangle extending linearly in the toe-heel direction, both ends of the rectangle reach the toe-side portion and heel-side portion that curve from the sole portion 22 toward the crown portion 21. Since the toe-side portion and heel-side portion that curve from the sole portion 22 toward the crown portion 21 are at a high position relative to the horizontal line H, the golf club head 1 will have a high center of gravity.

[0026] In contrast, when the second weight member 72 is crescent-shaped, the crescent extends in the toe-heel direction as a whole, while both ends of the crescent curve toward the back. Therefore, compared to the case of a long, narrow rectangle, both ends of the crescent can remain lower relative to the horizontal line H, which can suppress the golf club head 1 from having a high center of gravity. Also, since both ends of the crescent are located on the sole portion 22, the rigidity of the sole portion 22 is increased, which can suppress vibrations of the golf club head 1 during impact.

[0027] In a plan view, the second weight member 72 has, for example, a toe-heel length L1 of 40 mm or more and 95 mm or less. The length L1 is preferably 45 mm or more and 90 mm or less, and more preferably 50 mm or more and 85 mm or less. The maximum height of the second weight member 72 in the d2 direction is preferably 2 mm or more and 7 mm or less, decreasing as it extends toward the toe-heel direction. The maximum width of the second weight member 72 in the d3 direction is preferably 7 mm or more and 15 mm or less, narrowing as it extends toward the toe-heel direction.

[0028] A concave receiving portion 71x is formed on the bottom surface of the first weight member 71. The receiving portion 71x opens on the bottom surface side of the first weight member 71, as well as on the toe side and heel side of the side surface. The second weight member 72 is positioned integrally with the first weight member 71 by fitting its longitudinal central portion near the receiving portion 71x. The bottom surface of the second weight member 72 is, for example, flush with the bottom surface of the first weight member 71.

[0029] The specific gravity of the first weight member 71 is, for example, 8 to 14. The specific gravity of the second weight member 72 is less than the specific gravity of the first weight member 71 and greater than the specific gravity of the body 20. For example, tungsten, tungsten alloy, etc. can be used as the material for the first weight member 71. For example, stainless steel, titanium, aluminum, etc. can be used as the material for the second weight member 72.

[0030] If the specific gravity of the second weight member 72 is high, the position of the center of gravity G will change. However, by making the specific gravity of the second weight member 72 lower than that of the first weight member 71 and higher than that of the body 20, the change in the position of the center of gravity G can be suppressed.

[0031] The first weight member 71 is, for example, 10g or more and 60g or less. Preferably, the first weight member 71 is 15g or more and 55g or less, and more preferably 20g or more and 50g or less. By making the first weight member 71 10g or more, the effect of providing the first weight member 71 can be fully realized. By making the first weight member 71 60g or less, sufficient adhesive strength to the sole portion 22 can be ensured. The second weight member 72 is, for example, 3g or more and 12g or less. Preferably, the second weight member 72 is 4g or more and 11g or less, and more preferably 5g or more and 10g or less.

[0032] As shown in Figure 6, it is preferable that the weight member 70 is embedded between the fiber-reinforced resin sheet 221 forming the sole portion 22 and the fiber-reinforced resin sheet 222 laminated on the fiber-reinforced resin sheet 221. The fiber-reinforced resin sheets 221 and 222 are, for example, carbon fiber-reinforced resin sheets. The side of the fiber-reinforced resin sheet 221 facing the fiber-reinforced resin sheet 222 becomes the inner surface of the sole portion 22. By making the first weight member 71 a frustoconical shape, the adhesive strength with the fiber-reinforced resin sheets 221 and 222 can be improved compared to the case of a cylindrical shape.

[0033] In Figure 6, the bottom surfaces of the first weight member 71 and the second weight member 72 are in contact with the fiber-reinforced resin sheet 221. Furthermore, the top and side surfaces of the first weight member 71, and the top and side surfaces of the second weight member 72 exposed from the first weight member 71, are in contact with the fiber-reinforced resin sheet 222. In other words, the fiber-reinforced resin sheet 222 is positioned along the top surface of the weight member 70. Note that the fiber-reinforced resin sheet 221 and / or 222 may have a laminated structure of multiple layers of fiber-reinforced resin.

[0034] Thus, in the golf club head 1, the weight member 70 is sandwiched between layers of adjacent fiber-reinforced resin sheets and is not exposed to the inner or outer surface of the body portion 20. This structure allows the weight member 70 to be easily fixed to the inner surface of the sole portion 22. Furthermore, since the weight member 70 includes a second weight member 72 extending in the toe-heel direction in addition to the first weight member 71, it can be embedded between layers of adjacent fiber-reinforced resin sheets over a wider area compared to the case where only the first weight member 71 is used. As a result, it is possible to ensure sufficient embedding strength of the weight member 70 by the fiber-reinforced resin sheet, and the peeling of the fiber-reinforced resin sheet during impact can be suppressed. In order to suppress the peeling of the fiber-reinforced resin sheet during impact, it is preferable that the length L1 is within the aforementioned range.

[0035] The golf club head 1 can be manufactured, for example, using a mold assembly and a pneumatic molding apparatus. The mold assembly is assembleable and disassembled, and the pneumatic molding apparatus comprises an openable and closable sealed container, and a pressure generating mechanism and a heating mechanism attached to the openable and closable sealed container.

[0036] Specifically, the golf club head 1 is manufactured by, for example, the following method. First, a mold assembly that can be assembled and disassembled from one another is prepared. Then, multiple pre-impregnated materials made of fiber-reinforced resin are prepared, and these pre-impregnated materials are attached to the mold assembly in a layered manner to form the basic shape of the body 20.

[0037] Furthermore, in order to integrally mold the weight member 70 with the fiber-reinforced resin of the crown portion 21 and / or sole portion 22, when forming the basic shape of the body portion 20 by attaching multiple pre-soaking materials to the mold assembly in a layered manner, the weight member 70 can be placed within the basic shape of the body portion 20. Specifically, the weight member 70 may be attached to the pre-soaking material, or the weight member 70 may be wrapped in the pre-soaking material.

[0038] Next, the mold assembly containing the prototype of the body part 20 is placed in a bag. This bag is then placed in a resealable airtight container, and vacuum negative pressure is applied using a pressure generation mechanism, while heat is applied using a heating mechanism. As a result, the pre-impregnated material made of fiber-reinforced resin in the prototype of the body part 20 hardens through a cross-linking reaction. After the body part is heat-molded, it is bonded to the pre-molded face part 10 to form a semi-finished product of the golf club head 1. The burrs of this semi-finished product of the golf club head 1 are removed, and the surface is finished to complete the golf club head 1.

[0039] Furthermore, when applying vacuum negative pressure using a pressure generation mechanism and adding heat using a heating mechanism, for example, the vacuum negative pressure value can be set in the range of -0.1 mbar to -1000 mbar, the heating temperature in the range of 40°C to 250°C, and the time for applying vacuum negative pressure and heat can be set from 1 minute to 60 minutes.

[0040] As a pneumatic molding apparatus, for example, a pressure vessel can be used. When a pressure vessel is used as the pneumatic molding apparatus, the original shape of the golf club head 1 can be subjected to vacuum suction, heating, and air pressurization, and the pressure value of the pressurized air can be in the range of, for example, 2 bar to 100 bar.

[0041] Furthermore, the vacuum negative pressure value, heating temperature, and pressurized air pressure value can be adjusted, for example, by using wood-type golf club heads with different external shapes or pre-soaked materials made of fiber-reinforced resin with different thicknesses. Moreover, the vacuum negative pressure value, heating temperature, and pressurized air pressure value can also be adjusted according to the cross-linking reaction of the pre-soaked material made of fiber-reinforced resin. In other words, by forming the body from fiber-reinforced resin, it is easy to control the shape and weight of the golf club head.

[0042] Thus, the golf club head 1 is equipped with a weight member 70 on the inner surface of the sole portion 22. The weight member 70 includes a first weight member 71 positioned directly below the center of gravity G, and a second weight member 72 extending from the first weight member 71 in the toe-heel direction.

[0043] In a golf club head 1 with a large volume (400cc to 460cc), by placing the first weight member 71 directly below the center of gravity G, the user can feel that the golf club head 1 is easier to swing compared to when the first weight member 71 is placed at a position away from the center of gravity G. Furthermore, the user can feel that the golf club head 1 is easier to control.

[0044] Furthermore, if only the first weight member 71 were placed directly below the center of gravity G, the sound of impact would be unstable, and the strength of the golf club head would not be sufficient. By placing a second weight member 72 extending from the first weight member 71 in the toe-heel direction on the inner surface of the sole portion 22, in addition to the first weight member 71, the second weight member 72 acts as a rib, thereby stabilizing the sound of impact and improving the strength of the golf club head 1.

[0045] <Variation 1 of the First Embodiment> Modification 1 of the first embodiment shows an example of a golf club head in which a different material from that of the first embodiment is used for the body. In Modification 1 of the first embodiment, descriptions of components that are the same as those described in the previously described embodiment may be omitted.

[0046] Figure 7 is a perspective view illustrating a golf club head 1A according to Modification 1 of the First Embodiment. Figure 8 is a plan view illustrating a golf club head 1A according to Modification 1 of the First Embodiment. Figure 9 is a cross-sectional view illustrating a golf club head 1A according to Modification 1 of the First Embodiment. Note that Figure 9 shows a cross-section obtained by cutting the golf club head 1A through a plane that passes through the center of gravity G of the golf club head 1A, is perpendicular to the horizontal plane H (corresponding to the ground), and faces in the face-back direction, when the golf club head 1A is placed on the horizontal plane H (corresponding to the ground) according to the standard lie angle and standard loft angle. Figure 10 is a plan view illustrating the sole portion of the golf club head 1A according to Modification 1 of the First Embodiment, omitting the illustration of the upper part of the sole portion, and schematically showing the inner surface of the sole portion as viewed from the crown side.

[0047] The golf club head 1A shown in Figures 7 to 10 is a wood-type golf club head, such as a driver. The golf club head 1A comprises a face portion 10A, a body portion 20A, and a crown portion 30.

[0048] The body portion 20A has an opening that opens towards the face, and the face portion 10A is joined to close this opening. The body portion 20A also has an opening that opens towards the crown, and the crown portion 30 is joined to close this opening. The golf club head 1A is a hollow structure in which the body portion 20A, the face portion 10A and the crown portion 30 are joined to form a single unit. The volume of the golf club head 1A is between 400cc and 460cc.

[0049] The face portion 10A is the part that has a face surface 10f which serves as the striking surface. The face portion 10A has a predetermined thickness, and the face surface 10f forms the outer surface of the face portion 10A. The face portion 10A and the body portion 20A are made of metal, for example. The face portion 10A, the body portion 20A, and the crown portion 30 can be formed using, for example, titanium, titanium alloy, stainless steel, aluminum, aluminum alloy, ferrous metal, magnesium, magnesium alloy, etc. The face portion 10A may be formed using fiber-reinforced resin. The crown portion 30 may also be formed using fiber-reinforced resin.

[0050] The body portion 20A includes a sole portion 22. The body portion 20A may further include a hosel housing portion 23. The sole portion 22 is the part that forms the bottom of the golf club head 1A. The hosel housing portion 23 is the part that houses the hosel which is connected to the shaft. The crown portion 30 is the part that forms the upper part of the golf club head 1A.

[0051] Similar to golf club head 1, golf club head 1A is equipped with a weight member 70 on the inner surface of the sole portion 22. The weight member 70 includes a first weight member 71 and a second weight member 72, with the first weight member 71 positioned directly below the center of gravity G of golf club head 1A. Similar to golf club head 1, the weight member 70 is not visible from the outside of golf club head 1A.

[0052] The specific gravity and material of the first weight member 71 and the second weight member 72 can be the same as those of the golf club head 1, for example. The first weight member 71 is, for example, 10g or more and 30g or less. Preferably, the first weight member 71 is 12g or more and 28g or less, and more preferably 14g or more and 26g or less. The second weight member 72 is, for example, 2g or more and 10g or less. Preferably, the second weight member 72 is 2.5g or more and 9.5g or less, and more preferably 3g or more and 9g or less. The reason why the first weight member 71 and the second weight member 72 are lighter than the golf club head 1 is that the body portion 20A is heavier than the body portion 20 and has less excess weight, so the overall weight of the golf club head 1A is not made too heavy.

[0053] The golf club head 1A is provided with a protrusion 22x that projects from the outer side to the inner side of the sole portion 22. The protrusion 22x is for fastening the first weight member 71 and the second weight member 72. The weight member 70 is fastened to the protrusion 22x by the fastening portion 40. Furthermore, as shown in Figure 10, it is preferable that the sole portion 22 has a groove portion 22y in which the second weight member 72 is positioned. This allows the second weight member 72 to be positioned and prevents it from moving during impact.

[0054] Figure 11 shows an example of a method for fastening the weight member 70. Figure 11(a) shows a cross-section of the golf club head 1A when it is placed on the horizontal plane H in the same manner as in Figure 4, according to the reference lie angle and reference loft angle, and is cut by a plane that passes through the center of gravity G of the golf club head 1A, is perpendicular to the horizontal plane H, and faces in the face-back direction. Figure 11(b) is a view of the weight member 70 from the sole portion 22 side. Figure 11(c) is an exploded view of Figure 11(a).

[0055] As shown in Figure 11, a recess 72x is formed on the bottom surface of the second weight member 72, recessed to the receiving portion 71x side of the first weight member 71. The recess 72x is circular when viewed from the sole portion 22 side, for example. A through hole 72y is formed in the center of the recess 72x. The through hole 72y is circular with a smaller diameter than the recess 72x when viewed from the sole portion 22 side, for example. A female threaded portion 71y is formed in the center of the receiving portion 71x, communicating with the through hole 72y.

[0056] The fastening portion 40 comprises, for example, a head 41, a cylindrical portion 42, and a male threaded portion 43. The cylindrical portion 42 and the male threaded portion 43 are provided concentrically with the head 41 on one side of the head 41. The head 41 is circular when viewed, for example, from the sole portion 22 side. The cylindrical portion 42 and the male threaded portion 43 are circular with a smaller diameter than the head 41 when viewed, for example, from the crown portion 30 side.

[0057] The head 41 is provided with, for example, cross-shaped or hexagonal grooves. The head 41 does not protrude from the outer surface of the sole portion 22. As materials for the head 41, cylindrical portion 42, and male thread portion 43, metal members such as titanium, titanium alloy, aluminum, aluminum alloy, tungsten, tungsten alloy, stainless steel, and ferrous metals can be used.

[0058] To fasten the weight member 70 to the protrusion 22x, first, the recess 72x of the second weight member 72 is fitted into the protrusion 22x, and then the second weight member 72 is fitted into the receiving portion 71x of the first weight member 71. Then, the male threaded portion 43 side of the fastening part 40 is placed in the through hole 72y, and the tip of a Phillips screwdriver or hex wrench is inserted into the groove of the head 41 and the fastening part 40 is rotated, so that the male threaded portion 43 of the fastening part 40 can be screwed into the female threaded portion 71y of the first weight member 71. As a result, the weight member 70 is fastened to the protrusion 22x by the fastening part 40. Alternatively, the male threaded portion 43 of the fastening part 40 and the female threaded portion 71y of the first weight member 71 may be bonded together. This can improve the mounting strength of the weight member 70.

[0059] Thus, the first weight member 71 and the second weight member 72 are fastened to the protrusion 22x using different fastening methods. Specifically, the first weight member 71 can be fastened to the protrusion 22x of the sole portion 22 by screw fastening. The second weight member 72 can be fastened to the protrusion 22x by fitting it into the receiving portion 71x of the first weight member 71 and by screw fastening.

[0060] Thus, the golf club head 1A is equipped with a weight member 70 on the inner surface of the sole portion 22. The weight member 70 includes a first weight member 71 positioned directly below the center of gravity G, and a second weight member 72 extending from the first weight member 71 in the toe-heel direction. This allows the user to feel that the golf club head 1A is easy to swing, similar to the case of the golf club head 1. It also allows the user to feel that the golf club head 1A is easy to control.

[0061] Furthermore, similar to the case of the golf club head 1, by placing a second weight member 72 extending from the first weight member 71 in the toe-heel direction on the inner surface of the sole portion 22 in addition to the first weight member 71, the second weight member 72 acts as a rib, thereby stabilizing the sound of impact and improving the strength of the golf club head 1A.

[0062] Although preferred embodiments have been described in detail above, the invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the claims. [Explanation of Symbols]

[0063] 1.1A Golf Club Head 10,10A Face section 10f Face 20,20A Body section 21,30 Crown section 22 Sole 22x convex part 22y groove 23. Hosel Detention Unit 40 Fastening part 41 Head 42 Cylindrical section 43 Male threaded section 70 Weight component 71 First weight member 71x Receiving part 71y Female thread section 72 Second weight member 72x recess 72y through hole 221,222 Fiber-reinforced resin sheets

Claims

1. A golf club head having a volume of 400cc or more and 460cc or less, It comprises a face section with a face surface that serves as the striking surface, and a body section made of carbon, The body portion comprises a sole portion and a crown portion, A weight member is provided on the inner surface of the sole portion. The weight member includes a first weight member positioned directly below the center of gravity of the golf club head, and a second weight member extending from the first weight member in the toe-heel direction. The first weight member is positioned such that its bottom surface is in contact with the inner surface of the sole portion. The second weight member is positioned along the inner surface of the sole portion, In plan view, the second weight member is crescent-shaped, forming a golf club head.

2. A concave receiving portion is formed on the bottom surface of the first weight member. The golf club head according to claim 1, wherein the second weight member is fitted into the receiving portion and is positioned integrally with the first weight member.

3. The aforementioned body section is constructed by laminating carbon fiber reinforced resin sheets. The golf club head according to claim 1, wherein the first weight member and the second weight member are embedded between the layers of the carbon fiber reinforced resin sheet.

4. The first weight member weighs 20g or more and 50g or less. The golf club head according to claim 1, wherein the second weight member weighs 5g or more and 10g or less.

5. A golf club head having a volume of 400cc or more and 460cc or less, It comprises a face portion with a face surface that serves as the striking surface, and a metal body portion, The body portion comprises a sole portion, A weight member is provided on the inner surface of the sole portion. The weight member includes a first weight member positioned directly below the center of gravity of the golf club head, and a second weight member extending from the first weight member in the toe-heel direction. The first weight member is positioned such that its bottom surface is in contact with the inner surface of the sole portion. The second weight member is positioned along the inner surface of the sole portion, In plan view, the second weight member is crescent-shaped, forming a golf club head.

6. The sole portion has a projection that extends from the outer side to the inner side and has a protrusion for fastening the first weight member and the second weight member, The first weight member is fastened to the protrusion using the first fastening method, The golf club head according to claim 5, wherein the second weight member is fastened to the protrusion by the second fastening method.

7. The first weight member weighs 14g or more and 26g or less. The golf club head according to claim 5, wherein the second weight member weighs 3g or more and 9g or less.

8. The golf club head according to any one of claims 1 to 7, wherein the first weight member is frustoconical in shape and is positioned so that its base faces the inner surface of the sole portion.

9. In a plan view, the second weight member has a toe-heel length of 40 mm or more and 95 mm or less, as described in any one of claims 1 to 7, for a golf club head.

10. The specific gravity of the first weight member is 8 or more and 14 or less. The golf club head according to any one of claims 1 to 7, wherein the specific gravity of the second weight member is less than the specific gravity of the first weight member and greater than the specific gravity of the body portion.

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