Golf club head

Abstract

A golf club head includes a striking face. The head further includes: a head body having a face opening and a weight member receiving portion; a face member covering the face opening and forming at least a part of the striking face; a weight member inserted into the weight member receiving portion from a face side and fixed thereto; and a joint portion formed on a boundary between the weight member receiving portion and the weight member. The weight member receiving portion includes: a lower support portion supporting a lower side of the weight member; a toe-side support portion supporting a toe side of the weight member; a heel-side support portion supporting a heel side of the weight member; an upper support portion supporting an upper side of the weight member; and an upward opening formed by an absence of a portion of material in the upper support portion.

Description

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to Japanese Patent Application No. 2024-118939 filed on Jul. 24, 2024. The entire contents of this Japanese Patent Application are hereby incorporated by reference.BACKGROUNDTechnical Field

[0002] The present disclosure relates to golf club heads.Description of the Related Art

[0003] A golf club head including a weight member has been known. JP2020-178933A discloses a golf club head that includes a head body, a face plate fixed to the head body, and a weight member. In this head, the head body has a body recess that opens toward the face plate, and the weight member is inserted into the body recess.SUMMARY

[0004] A weight member enables adjustments of the position of the center of gravity and the weight distribution of a head. The inventor of the present disclosure has developed a new structure that includes a weight member and makes it possible to lower the position of the center of gravity for a head. One of the objectives of the present disclosure is to provide a golf club head including a weight member and having a lower center of gravity of the head.

[0005] In one aspect, a golf club head includes a striking face and a sole surface. The golf club head further includes: a head body that has a face opening and a weight member receiving portion; a face member that covers the face opening and forms at least a part of the striking face; a weight member that is inserted into the weight member receiving portion from a face side and fixed to the weight member receiving portion; and a joint portion formed on a boundary between the weight member receiving portion and the weight member. The weight member receiving portion includes: a lower support portion that supports a lower side of the weight member; a toe-side support portion that supports a toe side of the weight member; a heel-side support portion that supports a heel side of the weight member; an upper support portion that supports an upper side of the weight member; and an upward opening formed by an absence of a portion of material in the upper support portion.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 shows a golf club head according to a first embodiment as viewed from the front of its striking face;

[0007] FIG. 2 is the same drawing as FIG. 1, but additionally shows hidden lines with dashed lines;

[0008] FIG. 3 is a perspective view of the head in FIG. 1 as viewed from the back side;

[0009] FIG. 4 is an exploded perspective view of the head in FIG. 1;

[0010] FIG. 5 shows a head body of the head according to the first embodiment as viewed from the same viewpoint as in FIG. 1;

[0011] FIG. 6 is a perspective view of the head body of the head according to the first embodiment as viewed from the back side;

[0012] FIG. 7 is a cross-sectional view taken along line A-A in FIG. 2;

[0013] FIG. 8 is a cross-sectional view taken along line B-B in FIG. 2;

[0014] FIG. 9 is a cross-sectional view taken along line C-C in FIG. 2;

[0015] FIG. 10 is a cross-sectional view taken along line D-D in FIG. 2;

[0016] FIG. 11 is a cross-sectional view taken along line E-E in FIG. 2;

[0017] FIG. 12 shows a golf club head according to a second embodiment as viewed from the front of its striking face;

[0018] FIG. 13 is the same drawing as FIG. 12, but additionally shows hidden lines with dashed lines;

[0019] FIG. 14 is a perspective view of the head in FIG. 12 as viewed from the back side;

[0020] FIG. 15 is an exploded perspective view of the head in FIG. 12;

[0021] FIG. 16 shows a head body of the head according to the second embodiment as viewed from the same viewpoint as in FIG. 12;

[0022] FIG. 17 is a perspective view of the head body of the head according to the second embodiment as viewed from the back side;

[0023] FIG. 18 is a cross-sectional view taken along line A-A in FIG. 13;

[0024] FIG. 19 is a cross-sectional view taken along line B-B in FIG. 13;

[0025] FIG. 20 is a cross-sectional view taken along line C-C in FIG. 13;

[0026] FIG. 21 is a cross-sectional view taken along line D-D in FIG. 13;

[0027] FIG. 22 is a cross-sectional view taken along line E-E in FIG. 13;

[0028] FIG. 23 shows a golf club head according to a third embodiment as viewed from the front of its striking face;

[0029] FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate hidden lines;

[0030] FIG. 25 is a perspective view of the head in FIG. 23 as viewed from the back side;

[0031] FIG. 26 is an exploded perspective view of the head in FIG. 23;

[0032] FIG. 27 shows a head body of the head according to the third embodiment as viewed from the same viewpoint as in FIG. 23;

[0033] FIG. 28 is a perspective view of the head body of the head according to the third embodiment as viewed from the back side;

[0034] FIG. 29 is a cross-sectional view taken along line A-A in FIG. 24;

[0035] FIG. 30 is a cross-sectional view taken along line B-B in FIG. 24;

[0036] FIG. 31 is a cross-sectional view taken along line C-C in FIG. 24;

[0037] FIG. 32 is a cross-sectional view taken along line D-D in FIG. 24;

[0038] FIG. 33 is a cross-sectional view taken along line E-E in FIG. 24;

[0039] FIG. 34 is an exploded perspective view of a head according to a fourth embodiment;

[0040] FIG. 35 is a vertical cross-sectional view of a head according to a fifth embodiment;

[0041] FIG. 36A is a perspective view of the head body having a weight member attached thereto according to the first embodiment, FIG. 36B is a perspective view of the head body having a weight member attached thereto according to the second embodiment, and FIG. 36C is a perspective view of the head body having a weight member attached thereto according to the third embodiment; and

[0042] FIG. 37 is a conceptual diagram for illustrating a reference state.DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Hereinafter, the present disclosure will be described in detail based on preferred embodiments with appropriate references to the accompanying drawings. In the following embodiments, the same or common elements are denoted by the same reference symbols, and duplicated explanations will be omitted as appropriate.

[0044] The following terms are defined in the present disclosure.[Reference State]

[0045] In a head having a flat striking face such as an iron type head, the reference state refers to a state where a head is placed on a ground plane HP in a state where score lines and the ground plane HP are parallel to each other. In a head having a curved striking face such as a wood type head, the reference state refers to a state where a head is placed at a predetermined lie angle on the ground plane HP. In these reference states, the center line Z (shaft axis line Z) of a hosel hole of the head lies on (is contained in) a perpendicular plane VP (see FIG. 37). The perpendicular plane VP is a plane perpendicular to the ground plane HP.

[0046] When a head is in the reference state, its face angle is 0°. This means that, in a planar view of the head as viewed from above, a line normal to its striking face at the geometric center of the striking face is set to be perpendicular to an intersection line NL. The intersection line NL refers to an intersection line between the perpendicular plane VP and the ground plane HP. When the head has a flat striking face, the intersection line NL is parallel to the score lines.

[0047] A club including a mechanism that enables the adjustment of its loft angle, lie angle and face angle by changing the rotational position of a sleeve or the like provided at a tip portion of a shaft is known. In a head used for such a club, the shaft axis line Z of the head which is in the reference state is determined in a state where all adjustable items are set to a neutral position. The term “neutral” refers to the center of the adjustment range. To achieve this neutral setting for all adjustable items, a shaft equipped with a sleeve in which the shaft hole of the sleeve is not inclined relative to the outer shape of the sleeve, and where the center line of the sleeve coincides with the shaft axis, can be used.[Toe-Heel Direction]

[0048] The toe-heel direction is defined as the direction of the intersection line NL. In a head having a flat striking face, the toe-heel direction is parallel to the score lines.[Front-Rear Direction]

[0049] The front-rear direction is defined as a direction that is perpendicular to the toe-heel direction and parallel to the ground plane HP.[Face-Back Direction]

[0050] The face-back direction is defined as the direction of a normal line that is normal to a striking face at its face center. In a head having a flat striking face, the face-back direction is perpendicular to the striking face.[UP-Down Direction]

[0051] The up-down direction is the direction perpendicular to the ground plane HP.[Toe Reference Position]

[0052] A plurality of score lines have their respective toe-side ends. The position of the toe-most end among the toe-side ends is defined as the toe reference position. In a normal iron type golf club head, the toe-side ends of all the score lines coincide with each other, and this position of the toe-side ends is the toe reference position. In some iron type heads, such as wedges, the score lines are formed on substantially the entirety of the striking face. Such a head is also referred to as a full scoreline head. In such a head, the toe reference position can be a position that is spaced 18.5 mm apart from the toe-most point of the striking face toward the heel side. The toe reference position is a position in the toe-heel direction.[Heel Reference Position]

[0053] The score lines have their respective heel-side ends. The position of the heel-most end among the heel-side ends is the heel reference position. In a normal iron type golf club head, the position of the heel-side end of a longest score line coincides with the heel reference position. The heel reference position is a position in the toe-heel direction.[Score Line Center Position]

[0054] A position that divides a distance between the toe reference position and the heel reference position into two equal parts is defined as the score line center position. In a normal iron type golf club head, the center position of the longest score line coincides with the score line center position. The score line center position is a position in the toe-heel direction.[Toe Middle Position]

[0055] A position that divides a distance between the toe reference position and the score line center position into two equal parts is defined as the toe middle position. The toe middle position is a position in the toe-heel direction.[Heel Middle Position]

[0056] A position that divides a distance between the heel reference position and the score line center position into two equal parts is defined as the heel middle position. The heel middle position is a position in the toe-heel direction.[Vertical Cross Section]

[0057] The vertical cross section is a cross section taken along the face-back direction and the up-down direction. A drawing that shows a vertical cross section is referred to as a vertical cross-sectional view.[Leading Edge]

[0058] In a vertical cross section of a head, a point located at the front-most position in the front-rear direction is determined. This point is determined in each of vertical cross sections taken at different positions in the toe-heel direction. A set of these points is defined as the leading edge.[Trailing Edge]

[0059] When a radius of curvature of a sole surface is sequentially measured rearward in a vertical cross section of a head, a point at which the radius of curvature becomes first less than or equal to 5 mm is determined. This point is determined in each of vertical cross sections taken at different positions in the toe-heel direction. A set of these points is defined as the trailing edge. The trailing edge is the rear edge of the sole surface.[Face Center]

[0060] On the score line center position, a point that divides the width of the striking face into two equal parts is defined as the face center. In a head in which the score line center position cannot be determined, a geometric center (center of figure) of the striking face in a planar view of the striking face can be determined as the face center. The planar view of the striking face can be a projected figure of the striking face obtained by projecting the striking face onto a plane perpendicular to the face-back direction.

[0061] FIG. 1 shows a head 100 according to a first embodiment as viewed from the front of its striking face 102. FIG. 2 is the same drawing as FIG. 1, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 3 is a perspective view of the head 100 as viewed from the back side.

[0062] The head 100 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The sole surface 104a is the outer surface of the sole portion 104. The hosel 108 has a hosel hole 110. The hosel hole 110 has a center line Z. A shaft (not shown in the drawings) is attached to the hosel hole 110. The center line Z coincides with the shaft axis line. The striking face 102 and the sole surface 104a constitute a part of the outer surface of the head 100.

[0063] As shown in FIG. 3, the head 100 includes a leading edge Le and a trailing edge Te. The trailing edge Te is the rear edge of the sole surface 104a. The sole surface 104a includes a ridgeline 112 that extends from the toe side to the heel side. The ridgeline 112 is located between the leading edge Le and the trailing edge Te.

[0064] As shown in FIG. 1, the striking face 102 includes a plurality of score lines gv. The score lines gv include a longest score line gv1. All of the score lines gv are formed on the face member 122.

[0065] The head 100 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 3, the head 100 has a back cavity 114. The back cavity 114 is a cavity formed on the back side of the head 100. The back cavity 114 forms a cavity space SP. The cavity space SP refers to an internal empty space of the back cavity 114. An iron type head having such a back cavity 114 is referred to as a cavity back iron head by those skilled in the art. The head 100 is a cavity back iron head. Alternatively, the head 100 does not have to be a cavity back iron head. For example, the head 100 may be a muscle back iron head. In this case, the muscle back iron head may be a hollow iron head having a hollow interior. When the head 100 is a hollow iron head, a portion of an upper surface 162 of a weight member wt1 (described later), which is exposed by an upward opening 190, may face the hollow interior.

[0066] The head 100 includes a back surface 116. The back surface 116 is located at an upper position relative to the trailing edge Te. It should be noted that a portion located in the back cavity 114 (for example, a rear surface 152 of the face member 122) may be excluded from the back surface 116. The back surface 116 forms a part of the outer surface of the head 100.

[0067] Note that the head 100 does not have to be an iron type head. The head 100 may be a wood type head, a hybrid type head, or a putter type head. The striking face 102 does not have to be a flat surface. The head 100 is preferably an iron type head.

[0068] As shown in FIG. 1, the head 100 has a face center Fc, a toe reference position Pt, a heel reference position Ph, a score line center position Pc, a toe middle position Pt1 and a heel middle position Ph1. Definitions of these positions are as described above. In the present embodiment, the toe reference position Pt coincides with the position of the toe-side ends of the score lines gv.

[0069] FIG. 4 is an exploded perspective view of the head 100. FIG. 5 shows the head body 120 to which the weight member wt1 is attached. FIG. 6 is a perspective view of the head body 120 as viewed from the back side. In FIG. 4, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 4, the score lines gv on the face member 122 are omitted.

[0070] FIG. 7 is a cross-sectional view taken along line A-A in FIG. 2. FIG. 7 is a vertical cross-sectional view taken at a position on the toe side relative to the toe reference position Pt. FIG. 7 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 8 is a cross-sectional view taken along line B-B in FIG. 2. The line B-B is also shown in FIG. 1. FIG. 8 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 9 is a cross-sectional view taken along line C-C in FIG. 2. FIG. 9 is a vertical cross-sectional view taken at the score line center position Pc. The line C-C is also shown in FIG. 1. FIG. 10 is a cross-sectional view taken along line D-D in FIG. 2. FIG. 10 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 11 is a cross-sectional view taken along line E-E in FIG. 2. The line E-E is also shown in FIG. 1. FIG. 11 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of the positions of these cross sections, lines A-A to E-E are shown also in FIG. 5. In FIG. 5, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0071] The head 100 is constituted by a plurality of members. From the viewpoint of constituent members, the head 100 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. The weight member wt1 is fixed to the head body 120. The face member 122 forms at least a part of the striking face 102. In the present embodiment, the face member 122 forms the entirety of the striking face 102. The head body 120 forms at least a part of the sole portion 104 (sole surface 104a). In the present embodiment, the head body 120 forms the entirety of the sole portion 104 (sole surface 104a). The head body 120 forms the hosel 108.

[0072] As shown in FIG. 8, the weight member wt1 is located at the toe reference position Pt. As shown in FIG. 9, the weight member wt1 is located at the score line center position Pc. As shown in FIG. 11, the weight member wt1 is not located at the heel reference position Ph.

[0073] The head body 120 is made of a metal. Examples of the metal include stainless steel, soft iron, maraging steel, and a titanium alloy. In the present embodiment, the head body 120 is made of stainless steel. The face member 122 is made of a metal. Examples of the metal include a titanium alloy, stainless steel, chrome vanadium steel, and maraging steel. In the present embodiment, the face member 122 is made of a titanium alloy. There is no limitation on the materials of the head body 120 and the face member 122. From the viewpoint of forgiveness, the specific gravity of the face member 122 is preferably smaller than the specific gravity of the head body 120. In the present embodiment, the face member 122 is produced by forging. There is no limitation on the method for producing the face member 122.

[0074] The weight member wt1 is made of a metal. The specific gravity of the weight member wt1 is greater than the specific gravity of the head body 120. The specific gravity of the weight member wt1 is greater than the specific gravity of the face member 122. From the viewpoint of having a high specific gravity, the material of the weight member wt1 is preferably an alloy containing tungsten and / or nickel. Considering also formability, the material of the weight member wt1 is more preferably an alloy containing tungsten and nickel. The material of the weight member wt1 may be weldable to the head body 120, or may be non-weldable to the head body 120.

[0075] From the viewpoint of the design flexibility of the center of gravity of the head, the specific gravity of the weight member wt1 is preferably greater than or equal to 9.0, more preferably greater than or equal to 9.1, and still more preferably greater than or equal to 9.2. Considering availability of the material, the specific gravity of the weight member wt1 is preferably less than or equal to 20.0, more preferably less than or equal to 19.9, and still more preferably less than or equal to 19.8. Considering a material having a sufficient strength for the head body 120, the specific gravity of the head body 120 is preferably greater than or equal to 4.0, more preferably greater than or equal to 4.1, and still more preferably greater than or equal to 4.2. In order to enhance the design flexibility of the center of gravity of the head, the difference between the specific gravity of the head body 120 and the specific gravity of the weight member wt1 is preferably large. From this viewpoint, the specific gravity of the head body 120 is preferably less than or equal to 8.0, more preferably less than or equal to 7.95, and still more preferably less than or equal to 7.9. Considering a material having a sufficient strength for the face member 122, the specific gravity of the face member 122 is preferably greater than or equal to 4.0, more preferably greater than or equal to 4.1, and still more preferably greater than or equal to 4.2. In order to enhance the design flexibility of the center of gravity of the head, the difference between the specific gravity of the face member 122 and the specific gravity of the weight member wt1 is preferably large. From this viewpoint, the specific gravity of the face member 122 is preferably less than or equal to 8.0, more preferably less than or equal to 7.95, and still more preferably less than or equal to 7.9.

[0076] The entirety of the head body 120 is integrally formed as a single-piece member. Alternatively, a plurality of members may be joined together by, for example, welding to form the head body 120. The head body 120 is produced by casting. More specifically, the casting method is lost-wax precision casting. There is no limitation on the method for producing the head body 120.

[0077] The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122. The head body 120 forms a frame that surrounds the periphery of the face opening 134.

[0078] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134. The receiving surface 136 forms a flat surface. This flat surface is parallel to the striking face 102.

[0079] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0080] In the present embodiment, the face member 122 which is larger than the face opening 134 covers the face opening 134, whereby the face opening 134 is closed. Alternatively, the face member 122 may be fitted into the face opening 134.

[0081] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. The weight member wt1 is accommodated in the weight member receiving portion h1. The weight member wt1 is heled by the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. A wall that forms the recess has an upward opening (refer to upward opening 190, described later). The weight member receiving portion h1 is open toward the face side. The weight member wt1 is inserted into the weight member receiving portion h1 from the face side.

[0082] Note that the weight member receiving portion h1 does not have to be a recess. As described later, the weight member receiving portion h1 may be a through hole, for example.

[0083] The face member 122 has a plate shape as a whole. The face member 122 includes a front surface 150 and the rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136. The face member 122 does not have to have a plate shape.

[0084] For example, the face member 122 may be a cup face. The weight member wt1 includes a front surface 160, the upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. As shown in FIG. 7 to FIG. 10, the front surface 160 faces a pocket space SP1 of the cavity space SP. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0085] The center of gravity of the weight member wt1 is positioned on the toe side relative to the score line center position Pc. The center of gravity of the weight member wt1 is positioned on the toe side relative to the toe middle position Pt1. The weight member wt1 contributes to locating the center of gravity of the head at a toe-side position.

[0086] The center of gravity of the weight member wt1 is positioned on the sole side relative to the face center Fc. The entirety of the weight member wt1 is positioned on the sole side relative to the face center Fc. The weight member wt1 contributes to lowering the position of the center of gravity of the head.

[0087] The position of the weight member wt1 is not limited. In the present embodiment, the weight member wt1 includes a portion positioned on the toe side relative to the score line center position Pc. The weight member wt1 includes a portion positioned on the toe side relative to the toe reference position Pt. The weight member wt1 includes a portion positioned between the toe reference position Pt and the score line center position Pc. The weight member wt1 is not located at the heel reference position Ph. The entirety of the weight member wt1 is positioned on the toe side relative to the heel reference position Ph. The weight member wt1 is not located at the heel middle position Ph1. The entirety of the weight member wt1 is positioned on the toe side relative to the heel middle position Ph1. The center of gravity of the weight member wt1 is positioned on the sole side relative to the face center Fc. The entirety of the weight member wt1 is positioned on the sole side relative to the face center Fc.

[0088] As shown in FIG. 7 to FIG. 11, the head 100 has the pocket space SP1. The pocket space SP1 is a gap having a width in the face-back direction. The pocket space SP1 forms a part of the cavity space SP defined by the back cavity 114. The face-side boundary of the pocket space SP1 is defined by the rear surface 152 of the face member 122. The back-side boundary of the pocket space SP1 is defined by a surface opposite to the rear surface 152. The surface opposite to the rear surface 152 is formed by the head body 120 and / or the weight member wt1. The pocket space SP1 is continuous with an external space surrounding the head 100.

[0089] The surface defining the back-side boundary of the pocket space SP1 may include the front surface 160 of the weight member wt1. The front surface 160 faces the pocket space SP1. A gap between the front surface 160 and the rear surface 152 is included in the pocket space SP1. The front surface 160 is positioned opposite the rear surface 152.

[0090] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 4). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 7 to FIG. 10, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172. However, the joint portion 170 is not necessarily limited to the welded portion 172, and may alternatively be a portion joined by press fitting, or a portion bonded using an adhesive, for example. In FIG. 7 to FIG. 10, the joint portion 170 (welded portion 172) has a defined shape. However, the joint portion 170 is not required to have a specific shape. That is, the joint portion 170 (welded portion 172) may be only a portion present within the interface between the weigh member receiving portion h1 and the weight member wt1.

[0091] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only around the front surface 160 of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the pocket space SP1. The welded portion 172 is not present on the outer surface of the head 100. The position of the welded portion 172 is not limited.

[0092] The welded portion 172 is a portion formed by welding. Welding in the present disclosure includes fusion welding, pressure welding, brazing and soldering. In the welding of the present disclosure, either one of base materials (the head body 120 and the weight member wt1) may be melted, or both of the base materials may be melted. Alternatively, in the welding of the present disclosure, neither of the base materials are melted, and only a filler material (including brazing filler material) may be melted. The filler material may be used, or does not have to be used. The welded portion 172 is a concept including the following structure a, structure b, structure c, structure d, or structure e. A weld bead is an example of the welded portion 172.

[0093] (Structure a) A portion formed by melting and then solidifying a part of the head body 120 when the weight member wt1 is not melted

[0094] (Structure b) A portion formed by melting and then solidifying a part of the head body 120 and a part of the weight member wt1

[0095] (Structure c) A portion formed by melting and then solidifying a part of the head body 120 and a filler material when the weight member wt1 is not melted

[0096] (Structure d) A portion formed by melting and then solidifying a part of the head body 120, a part of the weight member wt1, and a filler material

[0097] (Structure e) A portion formed by melting and then solidifying only a filler material (brazing filler material) when neither the head body 120 nor the weight member wt1 is melted

[0098] The weight member wt1 may be integrated into the head body 120 with the welded portion 172. Alternatively, the weight member wt1 is not integrated into the head body 120, and may physically engage with the welded portion 172 integrated into the head body 120. Further alternatively, the weight member wt1 is not integrated into the head body 120 and may be joined to the head body 120 with a brazing filler material. As long as the welded portion 172 is positioned on the face side of the weight member wt1, and engages with the weight member receiving portion h1 so that the weight member wt1 cannot move backward, the welded portion 172 can fix the weight member wt1 even when the welded portion 172 only physically engages with the weight member wt1.

[0099] In the head 100, the welded portion 172 has the above structure d. That is, the welded portion 172 is formed by melting and then solidifying a part of the head body 120, a part of the weight member wt1, and a filler material.

[0100] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 7 to FIG. 10). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The outer surface of a wall forming the lower support portion 180 constitutes a part of the sole surface 104a. The lower support portion 180 abuts the lower surface 164 of the weight member wt1.

[0101] The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 4). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1.

[0102] The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1 (see FIG. 4). The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0103] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1 (see FIG. 4). The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a toe upper support portion 186a that supports the toe-side end of the weight member wt1 from the upper side, and a heel upper support portion 186b that supports the heel-side end of the weight member wt1 from the upper side. The toe upper support portion 186a extends from the toe-side support portion 182 and terminates at a position on the upper side of the weight member wt1. The heel upper support portion 186b extends from the heel-side support portion 184 and terminates at a position on the upper side of the weight member wt1.

[0104] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186 (see FIG. 4). Due to the presence of the upward opening 190, the weight member receiving portion h1 is open on its upper side. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. The upward opening 190 is positioned between the toe upper support portion 186a and the heel upper support portion 186b. The upper support portion 186 is separated into the toe upper support portion 186a and the heel upper support portion 186b by the upward opening 190.

[0105] The upward opening 190 penetrates through the upper support portion 186 in the face-back direction. Of the upper support portion 186, only the toe upper support portion 186a and the heel upper support portion 186b abut against the upper surface 162 of the weight member wt1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP, which is the internal empty space of the back cavity 114.

[0106] FIG. 12 shows a head 200 according to a second embodiment as viewed from the front of its striking face 102. FIG. 13 is the same drawing as FIG. 12, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 14 is a perspective view of the head 200 as viewed from the back side.

[0107] The head 200 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 has a hosel hole 110. The head 200 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 14, the head 200 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 200. The head 200 includes a back surface 116.

[0108] FIG. 15 is an exploded perspective view of the head 200. In FIG. 15, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 15, the score lines gv on the face member 122 are omitted. FIG. 16 is a front view of the head body 120 to which the weight member wt1 is attached. FIG. 17 is a perspective view of the head body 120 as viewed from the back side. FIG. 18 is a cross-sectional view taken along line A-A in FIG. 13. FIG. 18 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 19 is a cross-sectional view taken along line B-B in FIG. 13. FIG. 19 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 20 is a cross-sectional view taken along line C-C in FIG. 13. FIG. 20 is a vertical cross-sectional view taken at the score line center position Pc. FIG. 21 is a cross-sectional view taken along line D-D in FIG. 13. FIG. 21 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 22 is a cross-sectional view taken along line E-E in FIG. 13. FIG. 22 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of the positions of these cross sections, lines A-A to E-E are shown also in FIG. 16. In FIG. 16, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0109] The head 200 is constituted by a plurality of members. From the viewpoint of constituent members, the head 200 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. This fixing is achieved by welding. The weight member wt1 is fixed to the head body 120. The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122.

[0110] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134.

[0111] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0112] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. The weight member receiving portion h1 is open toward the face side.

[0113] The face member 122 includes a front surface 150 and a rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136.

[0114] The weight member wt1 includes a front surface 160, an upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. The front surface 160 faces the pocket space SP1. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0115] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 15). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 18 to FIG. 21, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172.

[0116] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the cavity space SP. The welded portion 172 is disposed only at a position that faces the pocket space SP1. The welded portion 172 is disposed only around the front surface 160.

[0117] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 18 to FIG. 21). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The lower support portion 180 abuts the lower surface 164 of the weight member wt1. The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 15). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1. The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1. The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0118] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1. The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a continuously extending part 186c that extends continuously from the toe-side support portion 182 to the heel-side support portion 184. The continuously extending part 186c is disposed on the face side. The continuously extending part 186c abuts the face-side edge part of the upper surface 162 of the weight member wt1 (see FIG. 19 and FIG. 20).

[0119] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186. The weight member receiving portion h1 is open on its upper side in the region where the upward opening 190 is located. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP. The upward opening 190 is located on the back side of the continuously extending part 186c. The head 200 of the present embodiment differs from the above-described head 100 only in the configurations of the upper support portion 186 and the upward opening 190.

[0120] The head 200 of the present embodiment also includes a toe upper support portion 186a and a heel upper support portion 186b. Although not shown in FIG. 15, FIG. 18 illustrates that the toe upper support portion 186a is disposed on the toe side of the upward opening 190 formed on the back side of the continuously extending part 186c. As shown in FIG. 15, the heel upper support portion 186b is disposed on the heel side of the upward opening 190 formed on the back side of the continuously extending part 186c. The upward opening 190 is located between the toe upper support portion 186a and the heel upper support portion 186b. The face-side end portion of the toe upper support portion 186a is continuous with the continuously extending part 186c. The face-side end portion of the heel upper support portion 186b is continuous with the continuously extending part 186c. The toe upper support portion 186a extends from the toe-side support portion 182 and supports the toe-side end portion of the weight member wt1 from the upper side. The heel upper support portion 186b extends from the heel-side support portion 184 and supports the heel-side end portion of the weight member wt1 from the upper side. Alternatively, the head does not necessarily have to include the toe upper support portion 186a or the heel upper support portion 186b.

[0121] FIG. 23 shows a head 300 according to a third embodiment as viewed from the front of its striking face 102. FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 25 is a perspective view of the head 300 as viewed from the back side.

[0122] The head 300 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 includes a hosel hole 110. The head 300 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 25, the head 300 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 300. The head 300 includes a back surface 116.

[0123] FIG. 26 is an exploded perspective view of the head 300. In FIG. 26, a weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 26, the score lines gv on the face member 122 are omitted. FIG. 27 is a front view of the head body 120 to which the weight member wt1 is attached. FIG. 28 is a perspective view of the head body 120 as viewed from the back side. FIG. 29 is a cross-sectional view taken along line A-A in FIG. 24. FIG. 29 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 30 is a cross-sectional view taken along line B-B in FIG. 24. FIG. 30 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 31 is a cross-sectional view taken along line C-C in FIG. 24. FIG. 31 is a vertical cross-sectional view taken at the score line center position Pc. FIG. 32 is a cross-sectional view taken along line D-D in FIG. 24. FIG. 32 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 33 is a cross-sectional view taken along line E-E in FIG. 24. FIG. 33 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of positions of these cross sections, lines A-A to E-E are shown also in FIG. 27. In FIG. 27, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0124] The head 300 is constituted by a plurality of members. From the viewpoint of constituent members, the head 300 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. The weight member wt1 is fixed to the head body 120. The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122.

[0125] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134.

[0126] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0127] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. The weight member receiving portion h1 is open toward the face side.

[0128] The face member 122 includes a front surface 150 and a rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136. The rear surface 152 faces the cavity space SP.

[0129] The weight member wt1 includes a front surface 160, an upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. The front surface 160 faces the pocket space SP1. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0130] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 26). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 29 to FIG. 32, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172.

[0131] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the cavity space SP. The welded portion 172 is disposed only at a position that faces the pocket space SP1.

[0132] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 29 to FIG. 32). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The lower support portion 180 abuts the lower surface 164 of the weight member wt1. The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 26). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1. The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1. The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0133] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1. The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a continuously extending part 186c that extends continuously from the toe-side support portion 182 to the heel-side support portion 184. The continuously extending part 186c is disposed on the back side. The continuously extending part 186c abuts the back-side edge part of the upper surface 162 of the weight member wt1. The back-side end portion of the continuously extending part 186c is continuous with a wall 188 that forms the back surface 116 (see FIG. 30 and FIG. 31).

[0134] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186. The weight member receiving portion h1 is open on its upper side in the region where the upward opening 190 is located. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP defined by the back cavity 114. The upward opening 190 is located on the face side (front side) of the continuously extending part 186c. The head 300 of the present embodiment differs from the above-described head 100 only in the configurations of the upper support portion 186 and the upward opening 190.

[0135] The head 300 of the present embodiment also includes a toe upper support portion 186a and a heel upper support portion 186b. As shown in FIG. 26, the toe upper support portion 186a is disposed on the toe side of the upward opening 190 formed on the front side of the continuously extending part 186c. The heel upper support portion 186b is disposed on the heel side of the upward opening 190 formed on the front side of the continuously extending part 186c. The upward opening 190 is located between the toe upper support portion 186a and the heel upper support portion 186b. The back-side end portion of the toe upper support portion 186a is continuous with the continuously extending part 186c. The back-side end portion of the heel upper support portion 186b is continuous with the continuously extending part 186c. The toe upper support portion 186a extends from the toe-side support portion 182 and supports the toe-side end portion of the weight member wt1 from the upper side. The heel upper support portion 186b extends from the heel-side support portion 184 and supports the heel-side end portion of the weight member wt1 from the upper side. Alternatively, the head does not necessarily have to include the toe upper support portion 186a or the heel upper support portion 186b.

[0136] FIG. 34 is an exploded perspective view of a head 400 according to a fourth embodiment. The head 400 includes a cover member 192. Except for the presence of the cover member 192, the head 400 has the same configuration as the head 100 of the first embodiment.

[0137] The cover member 192 covers the upper side of the weight member wt1. Of the upper surface 162 of the weight member wt1, a portion exposed to the cavity space SP by the upward opening 190 is covered by the cover member 192. The cover member 192 covers the weight member wt1 such that the weight member wt1 is not visible from the outside of the head 400. The upper surface 192a of the cover member 192 is exposed to the cavity space SP. The cover member 192 may be fixed to either the weight member wt1 or the head body 120.

[0138] A plate-shaped member may be used as the cover member 192, for example. A badge may be used as the cover member 192, for example. Examples of the material of the cover member 192 include resins, metals, and combinations thereof. From the viewpoint of not impairing the advantageous effects brought about by the upward opening 190, the specific gravity of the cover member 192 is preferably lower than the specific gravity of the head body 120. From this viewpoint, the specific gravity of the cover member 192 is preferably less than or equal to 3.0, more preferably less than or equal to 2.0, and still more preferably less than or equal to 1.5. Considering the availability of materials, the specific gravity of the cover member 192 is preferably greater than or equal to 0.8, more preferably greater than or equal to 0.9, and still more preferably greater than or equal to 1.0.

[0139] FIG. 35 is a cross-sectional view of a head 500 according to a fifth embodiment. FIG. 35 is a cross-sectional view taken at the position of the above-described line D-D. In the head 500, the weight member receiving portion h1 forms a through hole that penetrates through the head body 120. However, a wall that defines the through hole further has an upward opening 190 formed by an absence of a portion of material in the wall, in addition to the openings of the through hole. The weight member wt1 is exposed to the outside of the head 500 on the sole side and / or the back side. The head 500 has the same configuration as the head 100, except for the configurations of the weight member receiving portion h1 and the weight member wt1.

[0140] The weight member receiving portion h1 forms the through hole that is open toward both the face side and the back side. The weight member wt1 is inserted into the weight member receiving portion h1 from the face side. The weight member wt1 includes an exposed surface 194 that forms a part of the outer surface of the head 500. The exposed surface 194 forms a part of the sole surface 104a and / or a part of the back surface 116.

[0141] The weight member receiving portion h1 has a structure that prevents the weight member wt1 from passing through the weight member receiving portion h1 from the face side to the back side. When the weight member wt1 is inserted into the weight member receiving portion h1 from the face side, the weight member wt1 is retained by the weight member receiving portion h1 at a predetermined position in the face-back direction. The weight member receiving portion h1 includes a body tapered portion 196 that becomes narrower toward the back side. The body tapered portion 196 includes a first taper surface 196a and a second taper surface 196b that are disposed opposite each other, and the distance (shortest distance) between the first taper surface 196a and the second taper surface 196b decreases toward the back side. The weight member wt1 includes a taper abutment surface 198 that abuts the body tapered portion 196. The taper abutment surface 198 includes a first surface 198a and a second surface 198b. The distance (shortest distance) between the first surface 198a and the second surface 198b decreases toward the back side. The first surface 198a abuts the first taper surface 196a. The second surface 198b abuts the second taper surface 196b. As described above, the weight member receiving portion h1 may penetrate through the head body 120.

[0142] FIG. 36A is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 100 of the first embodiment. FIG. 36B is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 200 of the second embodiment. FIG. 36C is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 300 of the third embodiment. As described above, the weight member wt1 is fixed by the joint portion 170 in each embodiment. The joint portion 170 is the welded portion 172. The welded portion 172 is indicated by a bold solid line in FIG. 36A, FIG. 36B and FIG. 36C. In all embodiments, the welded portion 172 is disposed only on the periphery of the front surface 160 of the weight member wt1. In the first embodiment (FIG. 36A), the upward opening 190 penetrates through the upper support portion 186 from its front end to its rear end. In the first embodiment, the welded portion 172 is disposed around the front surface 160, excluding the region where the upward opening 190 is located. The welded portion 172 extends parallel to the toe upper support portion 186a, the toe-side support portion 182, the lower support portion 180, the heel-side support portion 184, and the heel upper support portion 186b. This holds true for the third embodiment (FIG. 36C). In the third embodiment (FIG. 36C), the upward opening 190 is located on the face side of the upper support portion 186. Also in the third embodiment, the welded portion 172 is disposed around the front surface 160, excluding the region where the upward opening 190 is located. The welded portion 172 extends parallel to the toe upper support portion 186a, the toe-side support portion 182, the lower support portion 180, the heel-side support portion 184, and the heel upper support portion 186b.

[0143] In the second embodiment (FIG. 36B), the upward opening 190 is located on the back side of the upper support portion 186. The upward opening 190 is not present on the face side of the weight member wt1 in the second embodiment. In the second embodiment, the face-side opening (opening for receiving the weight member wt1) of the weight member receiving portion h1 is a fully circumferential opening. The term “fully circumferential opening” refers to an opening defined by a continuous peripheral edge extending around its entire circumference. The welded portion 172 in the second embodiment is disposed around the entire circumference of the opening.

[0144] In all embodiments, the process for forming the joint portion 170 (welded portion 172) is carried out in a state where the face member 122 is not fixed to the head body 120. When the face member 122 is not fixed, the weight member receiving portion h1 is open toward the front side. This facilitates joining operations.

[0145] The above-shown embodiments exhibit the following advantageous effects.

[0146] In the first through fifth embodiments, the upward opening 190 is formed. The presence of the upward opening 190 can reduce the weight of the weight member receiving portion h1 on the upper side of the weight member wt1. This weight reduction can lower the position of the center of gravity of the head. The weight saved by the upward opening 190 can be allocated to other part(s), which can increase design flexibility for weight distribution of the head body 120. Allocating the saved weight to a lower-side part of the head body 120 can further lower the position of the center of gravity of the head. Allocating the saved weight to a toe-side part and / or a heel-side part of the head body 120 can increase the moment of inertia of the head.

[0147] The head body 120 including the weight member receiving portion h1 has a complicated shape. The head body 120 is often produced by casting. When the head body 120 is produced by casting, the wall constituting the weight member receiving portion h1 is required to have a wall thickness of greater than or equal to 2.5 mm to ensure castability. Because of this wall thickness, the weight member receiving portion h1 is required to have a large weight. In addition, increasing the dimensions of the weight member wt1 also increases the dimensions of the weight member receiving portion h1, which can further increase the weight of the wall in the upper part of the weight member receiving portion h1. The increased weight of the weight member receiving portion h1 can diminish the design advantage in the center of gravity of the head achieved through the weight member wt1. The wall of the upper part of the weight member receiving portion h1 is positioned on the upper side relative to the weight member wt1, and thus contributes less to lowering the position of the center of gravity of the head. The upward opening 190 can reduce the weight allocated to the portion located on the upper side relative to the weight member wt1, and can further lower the center of gravity of the head. The upward opening 190 can also effectively provide the above-mentioned saved weight. This can further enhance the effect of lowering the center of gravity brought about by the weight member wt1. This can also improve the flexibility of designing both the center of gravity of the head and weight distribution.

[0148] In the first through fifth embodiments, the upper support portion 186 is disposed in a region where the upward opening 190 is not present. Accordingly, the weight member wt1 cannot be removed upward from the weight member receiving portion h1.

[0149] In the first, fourth and fifth embodiments, the upward opening 190 penetrates through the upper support portion 186 in the face-back direction (see FIG. 36A). This structure can enlarge the area of the upward opening 190, thereby further reducing the weight of the upper support portion 186. Since the toe upper support portion 186a and the heel upper support portion 186b are disposed on both sides of the weight member wt1, the weight member wt1 cannot be removed upward from the weight member receiving portion h1.

[0150] In the second and third embodiments, the upper support portion 186 includes the continuously extending part 186c (see FIG. 36B and FIG. 36C). Accordingly, the reliability of fixation of the weight member wt1 is further enhanced. In the second embodiment, the joint portion 170 (welded portion 172) is disposed around the entire circumference of the weight member wt1. This structure further enhances the reliability of fixation of the weight member wt1. In the third embodiment, the continuously extending part 186c covers the rear edge part of the weight member wt1 from the upper side (see FIG. 30 and FIG. 31). The rear edge part of the weight member wt1 is not visible from the outside of the head 300. A gap between the rear edge part of the weight member wt1 and the head body 120 is not visible, either. This configuration can improve the appearance of the head 300.

[0151] In the fourth embodiment, the portion of the weight member wt1 exposed by the upward opening 190 is covered by the cover member 192. The weight member wt1 is not visible from the outside of the head 400. This configuration can improve the appearance of the head 400.

[0152] In the first through fifth embodiments, the weight member wt1 is inserted into the weight member receiving portion h1 from the face side, and is disposed at a position at which the weight member wt1 cannot move further backward. Accordingly, the weight member wt1 is securely fixed, even though the joint portion 170 (welded portion 172) is located only on the face side of the weight member wt1.

[0153] A double-pointed arrow D1 in FIG. 2 indicates the width of the weight member wt1. The width D1 is measured in the toe-heel direction. There is no limitation on the width D1. From the viewpoint of lowering the center of gravity of the head, the width D1 can be greater than or equal to 20 mm, further can be greater than or equal to 30 mm, and still further can be greater than or equal to 40 mm. From the viewpoint of dimensional restrictions on the head, the width D1 can be less than or equal to 70 mm, further can be less than or equal to 65 mm, and still further can be less than or equal to 60 mm.

[0154] A double-pointed arrow D2 in FIG. 2 indicates the width of the upward opening 190. The width D2 is measured in the toe-heel direction. There is no limitation on the width D2. From the viewpoint of increasing the above-mentioned saved weight, the ratio of the width D2 to the width D1 is preferably greater than or equal to 70%, more preferably greater than or equal to 75%, still more preferably greater than or equal to 80%, and yet more preferably greater than or equal to 85%. From the viewpoint of ensuring sufficient width for the toe upper support portion 186a and the heel upper support portion 186b, the ratio of the width D2 to the width D1 is preferably less than or equal to 95%, more preferably less than or equal to 92%, and still more preferably less than or equal to 90%.

[0155] The sum of the width (measured in the toe-heel direction) of the toe upper support portion 186a and the width (measured in the toe-heel direction) of the heel upper support portion 186b is equal to the difference (D1−D2). From the viewpoint of ensuring reliable fixation of the weight member wt1, the ratio of the difference (D1−D2) to the width D1 is preferably greater than or equal to 5%, more preferably greater than or equal to 8%, and still more preferably greater than or equal to 10%. From the viewpoint of ensuring sufficient width D2 of the upward opening 190, the ratio of the difference (D1−D2) to the width D1 is preferably less than or equal to 30%, more preferably less than or equal to 25%, still more preferably less than or equal to 20%, and yet more preferably less than or equal to 15%.

[0156] A double-pointed arrow D3 in FIG. 19 indicates the width of the continuously extending part 186c disposed on the face side. The width D3 is measured in the face-back direction. The width D3 is measured on the upper surface of the continuously extending part 186c. From the viewpoint of the amount of welding material permeated during the welding process, as well as from the viewpoint of preventing deformation during the welding process, the width D3 is preferably greater than or equal to 4 mm, more preferably greater than or equal to 4.5 mm, and still more preferably greater than or equal to 5 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the width D3 is preferably less than or equal to 12 mm, more preferably less than or equal to 10 mm, and still more preferably less than or equal to 8 mm. From the viewpoint of castability, the thickness of the continuously extending part 186c disposed on the face side is preferably greater than or equal to 2.5 mm, more preferably greater than or equal to 2.6 mm, and still more preferably greater than or equal to 2.7 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the thickness of the continuously extending part 186c disposed on the face side is preferably less than or equal to 6.0 mm, more preferably less than or equal to 5.5 mm, and still more preferably less than or equal to 5.0 mm.

[0157] A double-pointed arrow D4 in FIG. 30 indicates the width of the continuously extending part 186c disposed on the back side. The width D4 is measured in the face-back direction. The width D4 is measured on the upper surface of the continuously extending part 186c. From the viewpoint of concealing the rear edge part of the weight member wt1, the width D4 is preferably greater than or equal to 2 mm, more preferably greater than or equal to 2.5 mm, and still more preferably greater than or equal to 3 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the width D4 is preferably less than or equal to 10 mm, more preferably less than or equal to 8 mm, and still more preferably less than or equal to 6 mm. From the viewpoint of castability, the thickness of the continuously extending part 186c disposed on the back side is preferably greater than or equal to 2.5 mm, more preferably greater than or equal to 2.6 mm, and still more preferably greater than or equal to 2.7 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the thickness of the continuously extending part 186c disposed on the back side is preferably less than or equal to 6.0 mm, more preferably less than or equal to 5.5 mm, and still more preferably less than or equal to 5.0 mm.

[0158] In the second embodiment, the continuously extending part 186c is located at the face-most position. In this configuration, the continuously extending part 186c forms a portion of the wall that defines the opening for receiving the weight member receiving portion h1. In the third embodiment, the continuously extending part 186c is located at the back-most position. In this configuration, a back-side portion of the continuously extending part 186c is continuous with another portion (the wall 188, for example) of the head body. In contrast to the second and third embodiments, the continuously extending part 186c may be located at an intermediate position in the face-back direction. In this configuration, the upward opening 190 is formed on both the face side and the back side of the continuously extending part 186c.

[0159] From the viewpoint of lowering the center of gravity of the head, the weight saved by the upward opening 190 is preferably greater than or equal to 5 g, more preferably greater than or equal to 7 g, and still more preferably greater than or equal to 9 g. From the viewpoint of dimensional restrictions on the head, the weight saved by the upward opening 190 is preferably less than or equal to 20 g, more preferably less than or equal to 18 g, and still more preferably less than or equal to 16 g. The saved weight is the amount of weight removed from the upper support portion 186 by the upward opening 190. A part of the weight member wt1 that is exposed to the outside by the upward opening 190 has an area denoted by M (cm2). The thickness of the upper support portion 186 is denoted by t (cm). The specific gravity of the upper support portion 186 is denoted by S. The saved weight (grams) is calculated as M×t×S. As described above, a part of the upper surface 162 of the weight member wt1 is exposed to the cavity space SP. The area of the exposed part is denoted by M. The thickness t is the thickness of the upper support portion 186 in a region where the upward opening 190 is not formed. When the upper support portion 186 does not have a constant thickness, the thickness t is defined as the average thickness of the upper support portion 186. The average thickness can be calculated by dividing the volume of the upper support portion 186 by the area of the upper surface 162 covered by the upper support portion 186.

[0160] From the viewpoint of lowering the center of gravity of the head, the ratio of the saved weight to the head weight is preferably greater than or equal to 2%, more preferably greater than or equal to 2.5%, still more preferably greater than or equal to 3%, and yet more preferably greater than or equal to 3.5%. Considering the dimensional limitations of the weight member receiving portion h1, the ratio of the saved weight to the head weight is preferably less than or equal to 10%, more preferably less than or equal to 9%, and still more preferably less than or equal to 8%.

[0161] From the viewpoint of lowering the center of gravity of the head, the center of gravity of the weight member wt1 is preferably located on the lower side relative to the center of gravity of the head. From the viewpoint of a lateral moment of inertia, the center of gravity of the weight member wt1 is preferably located on the toe side relative to the face center Fc. In this configuration, the head weight is distributed toward peripheral portions in the toe-heel direction by the weight of the hosel 108 located on the heel side and the weight of the weight member wt1 located on the toe side. The lateral MI refers to the moment of inertia of a head about an axis that passes through the center of gravity of the head and extends in the up-down direction.

[0162] The method of producing the heads 100, 200, 300, 400, and 500 described in the above embodiments can include the following steps (1) to (3).

[0163] (1) A first step of inserting the weight member wt1 into the weight member receiving portion h1 of the head body 120 from the face side, prior to attaching the face member 122 to the head body 120.

[0164] (2) A second step of forming the joint portion 170 (welded portion 172) on the boundary between the weight member wt1 and the weight member receiving portion h1 on the face side of the weight member wt1 in the assembly produced during the first step.

[0165] (3) A third step of attaching the face member 122 to the head body 120 that has been processed in the second step.

[0166] The following clauses are part of the invention included in the present disclosure.[Clause 1]

[0167] A golf club head including a striking face and a sole surface, wherein

[0168] the golf club head further includes:

[0169] a head body that includes a face opening and a weight member receiving portion;

[0170] a face member that covers the face opening and forms at least a part of the striking face;

[0171] a weight member that is inserted into the weight member receiving portion from a face side and is fixed to the weight member receiving portion; and

[0172] a joint portion formed on a boundary between the weight member receiving portion and the weight member, and

[0173] the weight member receiving portion includes:

[0174] a lower support portion that supports a lower side of the weight member;

[0175] a toe-side support portion that supports a toe side of the weight member;

[0176] a heel-side support portion that supports a heel side of the weight member;

[0177] an upper support portion that supports an upper side of the weight member; and

[0178] an upward opening formed by an absence of a portion of material in the upper support portion.[Clause 2]

[0179] The golf club head according to clause 1, wherein

[0180] the upper support portion includes a toe upper support portion that extends from the toe-side support portion and supports a toe-side end of the weight member from an upper side, and a heel upper support portion that extends from the heel-side support portion and supports a heel-side end of the weight member from the upper side, and

[0181] the upward opening is located between the toe upper support portion and the heel upper support portion.[Clause 3]

[0182] The golf club head according to clause 1 or 2, wherein

[0183] the upward opening penetrates through the upper support portion in a face-back direction.[Clause 4]

[0184] The golf club head according to clause 1 or 2, wherein

[0185] the upper support portion includes a continuously extending part that extends continuously from the toe-side support portion to the heel-side support portion, and the upward opening is formed on a face side and / or a back side of the continuously extending part.[Clause 5]

[0186] The golf club head according to any one of clauses 1 to 4, wherein

[0187] the face member includes a front surface that forms at least a part of the striking face, and a rear surface that is a surface opposite to the front surface,

[0188] the weight member includes a front surface located on the face side, and

[0189] the rear surface of the face member and the front surface of the weight member face each other across a space.LIST OF REFERENCE SYMBOLS100, 200, 300, 400, 500 Golf club head

[0191] 102 Striking face

[0192] 104 Sole portion

[0193] 104a Sole surface

[0194] 108 Hosel

[0195] 114 Back cavity

[0196] 116 Back surface

[0197] 120 Head body

[0198] 122 Face member

[0199] 134 Face opening

[0200] 150 Front surface of the face member

[0201] 152 Rear surface of the face member

[0202] 170 Joint portion

[0203] 172 Welded portion

[0204] 180 Lower support portion of the weight member receiving portion

[0205] 182 Toe-side support portion of the weight member receiving portion

[0206] 184 Heel-side support portion of the weight member receiving portion

[0207] 186 Upper support portion of the weight member receiving portion

[0208] 186a Toe upper support portion

[0209] 186b Heel upper support portion

[0210] 186c Continuously extending part

[0211] 190 Upward opening

[0212] 192 Cover member

[0213] Fc Face center

[0214] SP Cavity space

[0215] SP1 Pocket space

[0216] h1 Weight member receiving portion

[0217] wt1 Weight member

[0218] gv Score lines

[0219] gv1 Longest score line

[0220] Pt Toe reference position

[0221] Pc Score line center position

[0222] Ph Heel reference position

[0223] Le Leading edge

[0224] Te Trailing edge

[0225] The foregoing descriptions are merely illustrative, and various modifications may be made without departing from the principles of the present disclosure.

[0226] The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The use of the terms “a”, “an”, “the”, and similar referents in the context of throughout this disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. As used throughout this disclosure, the word “may” is used in a permissive sense (i.e., meaning “having the potential to”), rather than the mandatory sense (i.e., meaning “must”). Similarly, as used throughout this disclosure, the terms “comprising,”“having,”“including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted.

Examples

first embodiment

[0061]FIG. 1 shows a head 100 as viewed from the front of its striking face 102. FIG. 2 is the same drawing as FIG. 1, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 3 is a perspective view of the head 100 as viewed from the back side.

[0062]The head 100 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The sole surface 104a is the outer surface of the sole portion 104. The hosel 108 has a hosel hole 110. The hosel hole 110 has a center line Z. A shaft (not shown in the drawings) is attached to the hosel hole 110. The center line Z coincides with the shaft axis line. The striking face 102 and the sole surface 104a constitute a part of the outer surface of the head 100.

[0063]As shown in FIG. 3, the head 100 includes a leading edge Le and a trailing edge Te. The trailing edge Te is the rear edge of the sole surface 10...

second embodiment

[0106]FIG. 12 shows a head 200 as viewed from the front of its striking face 102. FIG. 13 is the same drawing as FIG. 12, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 14 is a perspective view of the head 200 as viewed from the back side.

[0107]The head 200 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 has a hosel hole 110. The head 200 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 14, the head 200 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 200. The head 200 includes a back surface 116.

[0108]FIG. 15 is an exploded perspective view of the head 200. In FIG. 15, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 15, the score lines gv on the f...

third embodiment

[0121]FIG. 23 shows a head 300 as viewed from the front of its striking face 102. FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 25 is a perspective view of the head 300 as viewed from the back side.

[0122]The head 300 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 includes a hosel hole 110. The head 300 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 25, the head 300 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 300. The head 300 includes a back surface 116.

[0123]FIG. 26 is an exploded perspective view of the head 300. In FIG. 26, a weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 26, the score lines gv on th...

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to Japanese Patent Application No. 2024-118939 filed on Jul. 24, 2024. The entire contents of this Japanese Patent Application are hereby incorporated by reference.BACKGROUNDTechnical Field

[0002] The present disclosure relates to golf club heads.Description of the Related Art

[0003] A golf club head including a weight member has been known. JP2020-178933A discloses a golf club head that includes a head body, a face plate fixed to the head body, and a weight member. In this head, the head body has a body recess that opens toward the face plate, and the weight member is inserted into the body recess.SUMMARY

[0004] A weight member enables adjustments of the position of the center of gravity and the weight distribution of a head. The inventor of the present disclosure has developed a new structure that includes a weight member and makes it possible to lower the position of the center of gravity for a head. One of the objectives of the present disclosure is to provide a golf club head including a weight member and having a lower center of gravity of the head.

[0005] In one aspect, a golf club head includes a striking face and a sole surface. The golf club head further includes: a head body that has a face opening and a weight member receiving portion; a face member that covers the face opening and forms at least a part of the striking face; a weight member that is inserted into the weight member receiving portion from a face side and fixed to the weight member receiving portion; and a joint portion formed on a boundary between the weight member receiving portion and the weight member. The weight member receiving portion includes: a lower support portion that supports a lower side of the weight member; a toe-side support portion that supports a toe side of the weight member; a heel-side support portion that supports a heel side of the weight member; an upper support portion that supports an upper side of the weight member; and an upward opening formed by an absence of a portion of material in the upper support portion.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 shows a golf club head according to a first embodiment as viewed from the front of its striking face;

[0007] FIG. 2 is the same drawing as FIG. 1, but additionally shows hidden lines with dashed lines;

[0008] FIG. 3 is a perspective view of the head in FIG. 1 as viewed from the back side;

[0009] FIG. 4 is an exploded perspective view of the head in FIG. 1;

[0010] FIG. 5 shows a head body of the head according to the first embodiment as viewed from the same viewpoint as in FIG. 1;

[0011] FIG. 6 is a perspective view of the head body of the head according to the first embodiment as viewed from the back side;

[0012] FIG. 7 is a cross-sectional view taken along line A-A in FIG. 2;

[0013] FIG. 8 is a cross-sectional view taken along line B-B in FIG. 2;

[0014] FIG. 9 is a cross-sectional view taken along line C-C in FIG. 2;

[0015] FIG. 10 is a cross-sectional view taken along line D-D in FIG. 2;

[0016] FIG. 11 is a cross-sectional view taken along line E-E in FIG. 2;

[0017] FIG. 12 shows a golf club head according to a second embodiment as viewed from the front of its striking face;

[0018] FIG. 13 is the same drawing as FIG. 12, but additionally shows hidden lines with dashed lines;

[0019] FIG. 14 is a perspective view of the head in FIG. 12 as viewed from the back side;

[0020] FIG. 15 is an exploded perspective view of the head in FIG. 12;

[0021] FIG. 16 shows a head body of the head according to the second embodiment as viewed from the same viewpoint as in FIG. 12;

[0022] FIG. 17 is a perspective view of the head body of the head according to the second embodiment as viewed from the back side;

[0023] FIG. 18 is a cross-sectional view taken along line A-A in FIG. 13;

[0024] FIG. 19 is a cross-sectional view taken along line B-B in FIG. 13;

[0025] FIG. 20 is a cross-sectional view taken along line C-C in FIG. 13;

[0026] FIG. 21 is a cross-sectional view taken along line D-D in FIG. 13;

[0027] FIG. 22 is a cross-sectional view taken along line E-E in FIG. 13;

[0028] FIG. 23 shows a golf club head according to a third embodiment as viewed from the front of its striking face;

[0029] FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate hidden lines;

[0030] FIG. 25 is a perspective view of the head in FIG. 23 as viewed from the back side;

[0031] FIG. 26 is an exploded perspective view of the head in FIG. 23;

[0032] FIG. 27 shows a head body of the head according to the third embodiment as viewed from the same viewpoint as in FIG. 23;

[0033] FIG. 28 is a perspective view of the head body of the head according to the third embodiment as viewed from the back side;

[0034] FIG. 29 is a cross-sectional view taken along line A-A in FIG. 24;

[0035] FIG. 30 is a cross-sectional view taken along line B-B in FIG. 24;

[0036] FIG. 31 is a cross-sectional view taken along line C-C in FIG. 24;

[0037] FIG. 32 is a cross-sectional view taken along line D-D in FIG. 24;

[0038] FIG. 33 is a cross-sectional view taken along line E-E in FIG. 24;

[0039] FIG. 34 is an exploded perspective view of a head according to a fourth embodiment;

[0040] FIG. 35 is a vertical cross-sectional view of a head according to a fifth embodiment;

[0041] FIG. 36A is a perspective view of the head body having a weight member attached thereto according to the first embodiment, FIG. 36B is a perspective view of the head body having a weight member attached thereto according to the second embodiment, and FIG. 36C is a perspective view of the head body having a weight member attached thereto according to the third embodiment; and

[0042] FIG. 37 is a conceptual diagram for illustrating a reference state.DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Hereinafter, the present disclosure will be described in detail based on preferred embodiments with appropriate references to the accompanying drawings. In the following embodiments, the same or common elements are denoted by the same reference symbols, and duplicated explanations will be omitted as appropriate.

[0044] The following terms are defined in the present disclosure.[Reference State]

[0045] In a head having a flat striking face such as an iron type head, the reference state refers to a state where a head is placed on a ground plane HP in a state where score lines and the ground plane HP are parallel to each other. In a head having a curved striking face such as a wood type head, the reference state refers to a state where a head is placed at a predetermined lie angle on the ground plane HP. In these reference states, the center line Z (shaft axis line Z) of a hosel hole of the head lies on (is contained in) a perpendicular plane VP (see FIG. 37). The perpendicular plane VP is a plane perpendicular to the ground plane HP.

[0046] When a head is in the reference state, its face angle is 0°. This means that, in a planar view of the head as viewed from above, a line normal to its striking face at the geometric center of the striking face is set to be perpendicular to an intersection line NL. The intersection line NL refers to an intersection line between the perpendicular plane VP and the ground plane HP. When the head has a flat striking face, the intersection line NL is parallel to the score lines.

[0047] A club including a mechanism that enables the adjustment of its loft angle, lie angle and face angle by changing the rotational position of a sleeve or the like provided at a tip portion of a shaft is known. In a head used for such a club, the shaft axis line Z of the head which is in the reference state is determined in a state where all adjustable items are set to a neutral position. The term “neutral” refers to the center of the adjustment range. To achieve this neutral setting for all adjustable items, a shaft equipped with a sleeve in which the shaft hole of the sleeve is not inclined relative to the outer shape of the sleeve, and where the center line of the sleeve coincides with the shaft axis, can be used.[Toe-Heel Direction]

[0048] The toe-heel direction is defined as the direction of the intersection line NL. In a head having a flat striking face, the toe-heel direction is parallel to the score lines.[Front-Rear Direction]

[0049] The front-rear direction is defined as a direction that is perpendicular to the toe-heel direction and parallel to the ground plane HP.[Face-Back Direction]

[0050] The face-back direction is defined as the direction of a normal line that is normal to a striking face at its face center. In a head having a flat striking face, the face-back direction is perpendicular to the striking face.[UP-Down Direction]

[0051] The up-down direction is the direction perpendicular to the ground plane HP.[Toe Reference Position]

[0052] A plurality of score lines have their respective toe-side ends. The position of the toe-most end among the toe-side ends is defined as the toe reference position. In a normal iron type golf club head, the toe-side ends of all the score lines coincide with each other, and this position of the toe-side ends is the toe reference position. In some iron type heads, such as wedges, the score lines are formed on substantially the entirety of the striking face. Such a head is also referred to as a full scoreline head. In such a head, the toe reference position can be a position that is spaced 18.5 mm apart from the toe-most point of the striking face toward the heel side. The toe reference position is a position in the toe-heel direction.[Heel Reference Position]

[0053] The score lines have their respective heel-side ends. The position of the heel-most end among the heel-side ends is the heel reference position. In a normal iron type golf club head, the position of the heel-side end of a longest score line coincides with the heel reference position. The heel reference position is a position in the toe-heel direction.[Score Line Center Position]

[0054] A position that divides a distance between the toe reference position and the heel reference position into two equal parts is defined as the score line center position. In a normal iron type golf club head, the center position of the longest score line coincides with the score line center position. The score line center position is a position in the toe-heel direction.[Toe Middle Position]

[0055] A position that divides a distance between the toe reference position and the score line center position into two equal parts is defined as the toe middle position. The toe middle position is a position in the toe-heel direction.[Heel Middle Position]

[0056] A position that divides a distance between the heel reference position and the score line center position into two equal parts is defined as the heel middle position. The heel middle position is a position in the toe-heel direction.[Vertical Cross Section]

[0057] The vertical cross section is a cross section taken along the face-back direction and the up-down direction. A drawing that shows a vertical cross section is referred to as a vertical cross-sectional view.[Leading Edge]

[0058] In a vertical cross section of a head, a point located at the front-most position in the front-rear direction is determined. This point is determined in each of vertical cross sections taken at different positions in the toe-heel direction. A set of these points is defined as the leading edge.[Trailing Edge]

[0059] When a radius of curvature of a sole surface is sequentially measured rearward in a vertical cross section of a head, a point at which the radius of curvature becomes first less than or equal to 5 mm is determined. This point is determined in each of vertical cross sections taken at different positions in the toe-heel direction. A set of these points is defined as the trailing edge. The trailing edge is the rear edge of the sole surface.[Face Center]

[0060] On the score line center position, a point that divides the width of the striking face into two equal parts is defined as the face center. In a head in which the score line center position cannot be determined, a geometric center (center of figure) of the striking face in a planar view of the striking face can be determined as the face center. The planar view of the striking face can be a projected figure of the striking face obtained by projecting the striking face onto a plane perpendicular to the face-back direction.

[0061] FIG. 1 shows a head 100 according to a first embodiment as viewed from the front of its striking face 102. FIG. 2 is the same drawing as FIG. 1, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 3 is a perspective view of the head 100 as viewed from the back side.

[0062] The head 100 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The sole surface 104a is the outer surface of the sole portion 104. The hosel 108 has a hosel hole 110. The hosel hole 110 has a center line Z. A shaft (not shown in the drawings) is attached to the hosel hole 110. The center line Z coincides with the shaft axis line. The striking face 102 and the sole surface 104a constitute a part of the outer surface of the head 100.

[0063] As shown in FIG. 3, the head 100 includes a leading edge Le and a trailing edge Te. The trailing edge Te is the rear edge of the sole surface 104a. The sole surface 104a includes a ridgeline 112 that extends from the toe side to the heel side. The ridgeline 112 is located between the leading edge Le and the trailing edge Te.

[0064] As shown in FIG. 1, the striking face 102 includes a plurality of score lines gv. The score lines gv include a longest score line gv1. All of the score lines gv are formed on the face member 122.

[0065] The head 100 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 3, the head 100 has a back cavity 114. The back cavity 114 is a cavity formed on the back side of the head 100. The back cavity 114 forms a cavity space SP. The cavity space SP refers to an internal empty space of the back cavity 114. An iron type head having such a back cavity 114 is referred to as a cavity back iron head by those skilled in the art. The head 100 is a cavity back iron head. Alternatively, the head 100 does not have to be a cavity back iron head. For example, the head 100 may be a muscle back iron head. In this case, the muscle back iron head may be a hollow iron head having a hollow interior. When the head 100 is a hollow iron head, a portion of an upper surface 162 of a weight member wt1 (described later), which is exposed by an upward opening 190, may face the hollow interior.

[0066] The head 100 includes a back surface 116. The back surface 116 is located at an upper position relative to the trailing edge Te. It should be noted that a portion located in the back cavity 114 (for example, a rear surface 152 of the face member 122) may be excluded from the back surface 116. The back surface 116 forms a part of the outer surface of the head 100.

[0067] Note that the head 100 does not have to be an iron type head. The head 100 may be a wood type head, a hybrid type head, or a putter type head. The striking face 102 does not have to be a flat surface. The head 100 is preferably an iron type head.

[0068] As shown in FIG. 1, the head 100 has a face center Fc, a toe reference position Pt, a heel reference position Ph, a score line center position Pc, a toe middle position Pt1 and a heel middle position Ph1. Definitions of these positions are as described above. In the present embodiment, the toe reference position Pt coincides with the position of the toe-side ends of the score lines gv.

[0069] FIG. 4 is an exploded perspective view of the head 100. FIG. 5 shows the head body 120 to which the weight member wt1 is attached. FIG. 6 is a perspective view of the head body 120 as viewed from the back side. In FIG. 4, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 4, the score lines gv on the face member 122 are omitted.

[0070] FIG. 7 is a cross-sectional view taken along line A-A in FIG. 2. FIG. 7 is a vertical cross-sectional view taken at a position on the toe side relative to the toe reference position Pt. FIG. 7 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 8 is a cross-sectional view taken along line B-B in FIG. 2. The line B-B is also shown in FIG. 1. FIG. 8 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 9 is a cross-sectional view taken along line C-C in FIG. 2. FIG. 9 is a vertical cross-sectional view taken at the score line center position Pc. The line C-C is also shown in FIG. 1. FIG. 10 is a cross-sectional view taken along line D-D in FIG. 2. FIG. 10 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 11 is a cross-sectional view taken along line E-E in FIG. 2. The line E-E is also shown in FIG. 1. FIG. 11 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of the positions of these cross sections, lines A-A to E-E are shown also in FIG. 5. In FIG. 5, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0071] The head 100 is constituted by a plurality of members. From the viewpoint of constituent members, the head 100 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. The weight member wt1 is fixed to the head body 120. The face member 122 forms at least a part of the striking face 102. In the present embodiment, the face member 122 forms the entirety of the striking face 102. The head body 120 forms at least a part of the sole portion 104 (sole surface 104a). In the present embodiment, the head body 120 forms the entirety of the sole portion 104 (sole surface 104a). The head body 120 forms the hosel 108.

[0072] As shown in FIG. 8, the weight member wt1 is located at the toe reference position Pt. As shown in FIG. 9, the weight member wt1 is located at the score line center position Pc. As shown in FIG. 11, the weight member wt1 is not located at the heel reference position Ph.

[0073] The head body 120 is made of a metal. Examples of the metal include stainless steel, soft iron, maraging steel, and a titanium alloy. In the present embodiment, the head body 120 is made of stainless steel. The face member 122 is made of a metal. Examples of the metal include a titanium alloy, stainless steel, chrome vanadium steel, and maraging steel. In the present embodiment, the face member 122 is made of a titanium alloy. There is no limitation on the materials of the head body 120 and the face member 122. From the viewpoint of forgiveness, the specific gravity of the face member 122 is preferably smaller than the specific gravity of the head body 120. In the present embodiment, the face member 122 is produced by forging. There is no limitation on the method for producing the face member 122.

[0074] The weight member wt1 is made of a metal. The specific gravity of the weight member wt1 is greater than the specific gravity of the head body 120. The specific gravity of the weight member wt1 is greater than the specific gravity of the face member 122. From the viewpoint of having a high specific gravity, the material of the weight member wt1 is preferably an alloy containing tungsten and / or nickel. Considering also formability, the material of the weight member wt1 is more preferably an alloy containing tungsten and nickel. The material of the weight member wt1 may be weldable to the head body 120, or may be non-weldable to the head body 120.

[0075] From the viewpoint of the design flexibility of the center of gravity of the head, the specific gravity of the weight member wt1 is preferably greater than or equal to 9.0, more preferably greater than or equal to 9.1, and still more preferably greater than or equal to 9.2. Considering availability of the material, the specific gravity of the weight member wt1 is preferably less than or equal to 20.0, more preferably less than or equal to 19.9, and still more preferably less than or equal to 19.8. Considering a material having a sufficient strength for the head body 120, the specific gravity of the head body 120 is preferably greater than or equal to 4.0, more preferably greater than or equal to 4.1, and still more preferably greater than or equal to 4.2. In order to enhance the design flexibility of the center of gravity of the head, the difference between the specific gravity of the head body 120 and the specific gravity of the weight member wt1 is preferably large. From this viewpoint, the specific gravity of the head body 120 is preferably less than or equal to 8.0, more preferably less than or equal to 7.95, and still more preferably less than or equal to 7.9. Considering a material having a sufficient strength for the face member 122, the specific gravity of the face member 122 is preferably greater than or equal to 4.0, more preferably greater than or equal to 4.1, and still more preferably greater than or equal to 4.2. In order to enhance the design flexibility of the center of gravity of the head, the difference between the specific gravity of the face member 122 and the specific gravity of the weight member wt1 is preferably large. From this viewpoint, the specific gravity of the face member 122 is preferably less than or equal to 8.0, more preferably less than or equal to 7.95, and still more preferably less than or equal to 7.9.

[0076] The entirety of the head body 120 is integrally formed as a single-piece member. Alternatively, a plurality of members may be joined together by, for example, welding to form the head body 120. The head body 120 is produced by casting. More specifically, the casting method is lost-wax precision casting. There is no limitation on the method for producing the head body 120.

[0077] The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122. The head body 120 forms a frame that surrounds the periphery of the face opening 134.

[0078] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134. The receiving surface 136 forms a flat surface. This flat surface is parallel to the striking face 102.

[0079] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0080] In the present embodiment, the face member 122 which is larger than the face opening 134 covers the face opening 134, whereby the face opening 134 is closed. Alternatively, the face member 122 may be fitted into the face opening 134.

[0081] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. The weight member wt1 is accommodated in the weight member receiving portion h1. The weight member wt1 is heled by the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. A wall that forms the recess has an upward opening (refer to upward opening 190, described later). The weight member receiving portion h1 is open toward the face side. The weight member wt1 is inserted into the weight member receiving portion h1 from the face side.

[0082] Note that the weight member receiving portion h1 does not have to be a recess. As described later, the weight member receiving portion h1 may be a through hole, for example.

[0083] The face member 122 has a plate shape as a whole. The face member 122 includes a front surface 150 and the rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136. The face member 122 does not have to have a plate shape.

[0084] For example, the face member 122 may be a cup face. The weight member wt1 includes a front surface 160, the upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. As shown in FIG. 7 to FIG. 10, the front surface 160 faces a pocket space SP1 of the cavity space SP. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0085] The center of gravity of the weight member wt1 is positioned on the toe side relative to the score line center position Pc. The center of gravity of the weight member wt1 is positioned on the toe side relative to the toe middle position Pt1. The weight member wt1 contributes to locating the center of gravity of the head at a toe-side position.

[0086] The center of gravity of the weight member wt1 is positioned on the sole side relative to the face center Fc. The entirety of the weight member wt1 is positioned on the sole side relative to the face center Fc. The weight member wt1 contributes to lowering the position of the center of gravity of the head.

[0087] The position of the weight member wt1 is not limited. In the present embodiment, the weight member wt1 includes a portion positioned on the toe side relative to the score line center position Pc. The weight member wt1 includes a portion positioned on the toe side relative to the toe reference position Pt. The weight member wt1 includes a portion positioned between the toe reference position Pt and the score line center position Pc. The weight member wt1 is not located at the heel reference position Ph. The entirety of the weight member wt1 is positioned on the toe side relative to the heel reference position Ph. The weight member wt1 is not located at the heel middle position Ph1. The entirety of the weight member wt1 is positioned on the toe side relative to the heel middle position Ph1. The center of gravity of the weight member wt1 is positioned on the sole side relative to the face center Fc. The entirety of the weight member wt1 is positioned on the sole side relative to the face center Fc.

[0088] As shown in FIG. 7 to FIG. 11, the head 100 has the pocket space SP1. The pocket space SP1 is a gap having a width in the face-back direction. The pocket space SP1 forms a part of the cavity space SP defined by the back cavity 114. The face-side boundary of the pocket space SP1 is defined by the rear surface 152 of the face member 122. The back-side boundary of the pocket space SP1 is defined by a surface opposite to the rear surface 152. The surface opposite to the rear surface 152 is formed by the head body 120 and / or the weight member wt1. The pocket space SP1 is continuous with an external space surrounding the head 100.

[0089] The surface defining the back-side boundary of the pocket space SP1 may include the front surface 160 of the weight member wt1. The front surface 160 faces the pocket space SP1. A gap between the front surface 160 and the rear surface 152 is included in the pocket space SP1. The front surface 160 is positioned opposite the rear surface 152.

[0090] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 4). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 7 to FIG. 10, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172. However, the joint portion 170 is not necessarily limited to the welded portion 172, and may alternatively be a portion joined by press fitting, or a portion bonded using an adhesive, for example. In FIG. 7 to FIG. 10, the joint portion 170 (welded portion 172) has a defined shape. However, the joint portion 170 is not required to have a specific shape. That is, the joint portion 170 (welded portion 172) may be only a portion present within the interface between the weigh member receiving portion h1 and the weight member wt1.

[0091] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only around the front surface 160 of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the pocket space SP1. The welded portion 172 is not present on the outer surface of the head 100. The position of the welded portion 172 is not limited.

[0092] The welded portion 172 is a portion formed by welding. Welding in the present disclosure includes fusion welding, pressure welding, brazing and soldering. In the welding of the present disclosure, either one of base materials (the head body 120 and the weight member wt1) may be melted, or both of the base materials may be melted. Alternatively, in the welding of the present disclosure, neither of the base materials are melted, and only a filler material (including brazing filler material) may be melted. The filler material may be used, or does not have to be used. The welded portion 172 is a concept including the following structure a, structure b, structure c, structure d, or structure e. A weld bead is an example of the welded portion 172.

[0093] (Structure a) A portion formed by melting and then solidifying a part of the head body 120 when the weight member wt1 is not melted

[0094] (Structure b) A portion formed by melting and then solidifying a part of the head body 120 and a part of the weight member wt1

[0095] (Structure c) A portion formed by melting and then solidifying a part of the head body 120 and a filler material when the weight member wt1 is not melted

[0096] (Structure d) A portion formed by melting and then solidifying a part of the head body 120, a part of the weight member wt1, and a filler material

[0097] (Structure e) A portion formed by melting and then solidifying only a filler material (brazing filler material) when neither the head body 120 nor the weight member wt1 is melted

[0098] The weight member wt1 may be integrated into the head body 120 with the welded portion 172. Alternatively, the weight member wt1 is not integrated into the head body 120, and may physically engage with the welded portion 172 integrated into the head body 120. Further alternatively, the weight member wt1 is not integrated into the head body 120 and may be joined to the head body 120 with a brazing filler material. As long as the welded portion 172 is positioned on the face side of the weight member wt1, and engages with the weight member receiving portion h1 so that the weight member wt1 cannot move backward, the welded portion 172 can fix the weight member wt1 even when the welded portion 172 only physically engages with the weight member wt1.

[0099] In the head 100, the welded portion 172 has the above structure d. That is, the welded portion 172 is formed by melting and then solidifying a part of the head body 120, a part of the weight member wt1, and a filler material.

[0100] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 7 to FIG. 10). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The outer surface of a wall forming the lower support portion 180 constitutes a part of the sole surface 104a. The lower support portion 180 abuts the lower surface 164 of the weight member wt1.

[0101] The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 4). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1.

[0102] The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1 (see FIG. 4). The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0103] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1 (see FIG. 4). The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a toe upper support portion 186a that supports the toe-side end of the weight member wt1 from the upper side, and a heel upper support portion 186b that supports the heel-side end of the weight member wt1 from the upper side. The toe upper support portion 186a extends from the toe-side support portion 182 and terminates at a position on the upper side of the weight member wt1. The heel upper support portion 186b extends from the heel-side support portion 184 and terminates at a position on the upper side of the weight member wt1.

[0104] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186 (see FIG. 4). Due to the presence of the upward opening 190, the weight member receiving portion h1 is open on its upper side. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. The upward opening 190 is positioned between the toe upper support portion 186a and the heel upper support portion 186b. The upper support portion 186 is separated into the toe upper support portion 186a and the heel upper support portion 186b by the upward opening 190.

[0105] The upward opening 190 penetrates through the upper support portion 186 in the face-back direction. Of the upper support portion 186, only the toe upper support portion 186a and the heel upper support portion 186b abut against the upper surface 162 of the weight member wt1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP, which is the internal empty space of the back cavity 114.

[0106] FIG. 12 shows a head 200 according to a second embodiment as viewed from the front of its striking face 102. FIG. 13 is the same drawing as FIG. 12, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 14 is a perspective view of the head 200 as viewed from the back side.

[0107] The head 200 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 has a hosel hole 110. The head 200 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 14, the head 200 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 200. The head 200 includes a back surface 116.

[0108] FIG. 15 is an exploded perspective view of the head 200. In FIG. 15, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 15, the score lines gv on the face member 122 are omitted. FIG. 16 is a front view of the head body 120 to which the weight member wt1 is attached. FIG. 17 is a perspective view of the head body 120 as viewed from the back side. FIG. 18 is a cross-sectional view taken along line A-A in FIG. 13. FIG. 18 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 19 is a cross-sectional view taken along line B-B in FIG. 13. FIG. 19 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 20 is a cross-sectional view taken along line C-C in FIG. 13. FIG. 20 is a vertical cross-sectional view taken at the score line center position Pc. FIG. 21 is a cross-sectional view taken along line D-D in FIG. 13. FIG. 21 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 22 is a cross-sectional view taken along line E-E in FIG. 13. FIG. 22 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of the positions of these cross sections, lines A-A to E-E are shown also in FIG. 16. In FIG. 16, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0109] The head 200 is constituted by a plurality of members. From the viewpoint of constituent members, the head 200 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. This fixing is achieved by welding. The weight member wt1 is fixed to the head body 120. The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122.

[0110] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134.

[0111] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0112] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. The weight member receiving portion h1 is open toward the face side.

[0113] The face member 122 includes a front surface 150 and a rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136.

[0114] The weight member wt1 includes a front surface 160, an upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. The front surface 160 faces the pocket space SP1. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0115] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 15). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 18 to FIG. 21, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172.

[0116] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the cavity space SP. The welded portion 172 is disposed only at a position that faces the pocket space SP1. The welded portion 172 is disposed only around the front surface 160.

[0117] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 18 to FIG. 21). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The lower support portion 180 abuts the lower surface 164 of the weight member wt1. The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 15). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1. The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1. The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0118] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1. The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a continuously extending part 186c that extends continuously from the toe-side support portion 182 to the heel-side support portion 184. The continuously extending part 186c is disposed on the face side. The continuously extending part 186c abuts the face-side edge part of the upper surface 162 of the weight member wt1 (see FIG. 19 and FIG. 20).

[0119] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186. The weight member receiving portion h1 is open on its upper side in the region where the upward opening 190 is located. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP. The upward opening 190 is located on the back side of the continuously extending part 186c. The head 200 of the present embodiment differs from the above-described head 100 only in the configurations of the upper support portion 186 and the upward opening 190.

[0120] The head 200 of the present embodiment also includes a toe upper support portion 186a and a heel upper support portion 186b. Although not shown in FIG. 15, FIG. 18 illustrates that the toe upper support portion 186a is disposed on the toe side of the upward opening 190 formed on the back side of the continuously extending part 186c. As shown in FIG. 15, the heel upper support portion 186b is disposed on the heel side of the upward opening 190 formed on the back side of the continuously extending part 186c. The upward opening 190 is located between the toe upper support portion 186a and the heel upper support portion 186b. The face-side end portion of the toe upper support portion 186a is continuous with the continuously extending part 186c. The face-side end portion of the heel upper support portion 186b is continuous with the continuously extending part 186c. The toe upper support portion 186a extends from the toe-side support portion 182 and supports the toe-side end portion of the weight member wt1 from the upper side. The heel upper support portion 186b extends from the heel-side support portion 184 and supports the heel-side end portion of the weight member wt1 from the upper side. Alternatively, the head does not necessarily have to include the toe upper support portion 186a or the heel upper support portion 186b.

[0121] FIG. 23 shows a head 300 according to a third embodiment as viewed from the front of its striking face 102. FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 25 is a perspective view of the head 300 as viewed from the back side.

[0122] The head 300 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 includes a hosel hole 110. The head 300 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 25, the head 300 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 300. The head 300 includes a back surface 116.

[0123] FIG. 26 is an exploded perspective view of the head 300. In FIG. 26, a weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 26, the score lines gv on the face member 122 are omitted. FIG. 27 is a front view of the head body 120 to which the weight member wt1 is attached. FIG. 28 is a perspective view of the head body 120 as viewed from the back side. FIG. 29 is a cross-sectional view taken along line A-A in FIG. 24. FIG. 29 is a cross-sectional view taken at the position of the toe-side end of the weight member wt1. FIG. 30 is a cross-sectional view taken along line B-B in FIG. 24. FIG. 30 is a vertical cross-sectional view taken at the toe reference position Pt. FIG. 31 is a cross-sectional view taken along line C-C in FIG. 24. FIG. 31 is a vertical cross-sectional view taken at the score line center position Pc. FIG. 32 is a cross-sectional view taken along line D-D in FIG. 24. FIG. 32 is a vertical cross-sectional view taken at the position of the heel-side end of the weight member wt1. FIG. 33 is a cross-sectional view taken along line E-E in FIG. 24. FIG. 33 is a vertical cross-sectional view taken at the heel reference position Ph. For easy understanding of positions of these cross sections, lines A-A to E-E are shown also in FIG. 27. In FIG. 27, lines A-A to E-E are indicated by dash-dot-dot-dash lines.

[0124] The head 300 is constituted by a plurality of members. From the viewpoint of constituent members, the head 300 includes the head body 120, the face member 122, and the weight member wt1. The face member 122 is fixed to the head body 120. The weight member wt1 is fixed to the head body 120. The head body 120 has a face opening 134. The face opening 134 penetrates through the head body 120 in the face-back direction. The face opening 134 is covered by the face member 122.

[0125] The head body 120 includes a receiving surface 136. The receiving surface 136 is a surface that faces toward the face side. The receiving surface 136 supports the peripheral part of the face member 122 from the back side. In the present embodiment, the receiving surface 136 is disposed outside and around the face opening 134. The receiving surface 136 extends along an opening edge 138 of the face opening 134.

[0126] The head body 120 includes a heel stepped surface 140. The heel stepped surface 140 extends frontward from the receiving surface 136. The height of the heel stepped surface 140 is equal to the wall thickness of the face member 122. The heel stepped surface 140 abuts a side surface 142 on the heel side of the face member 122.

[0127] The head body 120 includes a weight member receiving portion h1. The weight member wt1 is inserted into the weight member receiving portion h1. In the present embodiment, the weight member receiving portion h1 is a recess. The weight member receiving portion h1 is open toward the face side.

[0128] The face member 122 includes a front surface 150 and a rear surface 152. The front surface 150 forms at least a part of the striking face 102. In the present embodiment, the front surface 150 constitutes the entirety of the striking face 102. The rear surface 152 is a surface opposite to the front surface 150. The peripheral part of the rear surface 152 abuts the receiving surface 136. The rear surface 152 faces the cavity space SP.

[0129] The weight member wt1 includes a front surface 160, an upper surface 162, a lower surface 164, and a side surface 168. The side surface 168 includes a toe side surface 168a and a heel side surface 168b. The front surface 160 faces the pocket space SP1. The front surface 160 forms an opposite surface that is opposite to the rear surface 152 of the face member 122. The front surface 160 and the rear surface 152 face each other across the space (cavity space SP, pocket space SP1). The lower surface 164 abuts the inner surface of the weight member receiving portion h1. The side surface 168 abuts the inner surface of the weight member receiving portion h1.

[0130] The weight member wt1 is inserted into the weight member receiving portion h1 from the face side (see dashed-line arrow in FIG. 26). The weight member wt1 is fixed to the weight member receiving portion h1. As shown in FIG. 29 to FIG. 32, a joint portion 170 is formed on the boundary between the weight member receiving portion h1 and the weight member wt1. In the present embodiment, the joint portion 170 is a welded portion 172.

[0131] In the present embodiment, the welded portion 172 is disposed on the face side of the weight member wt1. The welded portion 172 is disposed only on the face side of the weight member wt1. The welded portion 172 is disposed only at a position that faces the cavity space SP. The welded portion 172 is disposed only at a position that faces the pocket space SP1.

[0132] The weight member receiving portion h1 includes a lower support portion 180 that supports the lower side of the weight member wt1 (see FIG. 29 to FIG. 32). In the present embodiment, the lower support portion 180 is formed by a part of the sole portion 104. The lower support portion 180 abuts the lower surface 164 of the weight member wt1. The weight member receiving portion h1 includes a toe-side support portion 182 that supports the toe side of the weight member wt1 (see FIG. 26). The toe-side support portion 182 abuts the toe side surface 168a of the weight member wt1. The weight member receiving portion h1 includes a heel-side support portion 184 that supports the heel side of the weight member wt1. The heel-side support portion 184 abuts the heel side surface 168b of the weight member wt1.

[0133] The weight member receiving portion h1 includes an upper support portion 186 that supports the upper side of the weight member wt1. The upper support portion 186 abuts the upper surface 162 of the weight member wt1. The upper support portion 186 includes a continuously extending part 186c that extends continuously from the toe-side support portion 182 to the heel-side support portion 184. The continuously extending part 186c is disposed on the back side. The continuously extending part 186c abuts the back-side edge part of the upper surface 162 of the weight member wt1. The back-side end portion of the continuously extending part 186c is continuous with a wall 188 that forms the back surface 116 (see FIG. 30 and FIG. 31).

[0134] The weight member receiving portion h1 has an upward opening 190 formed by an absence of a portion of material in the upper support portion 186. The weight member receiving portion h1 is open on its upper side in the region where the upward opening 190 is located. The upward opening 190 prevents a part of the upper surface 162 of the weight member wt1 from abutting the weight member receiving portion h1. In the region where the upward opening 190 is located, the upper surface 162 of the weight member wt1 is exposed to the cavity space SP defined by the back cavity 114. The upward opening 190 is located on the face side (front side) of the continuously extending part 186c. The head 300 of the present embodiment differs from the above-described head 100 only in the configurations of the upper support portion 186 and the upward opening 190.

[0135] The head 300 of the present embodiment also includes a toe upper support portion 186a and a heel upper support portion 186b. As shown in FIG. 26, the toe upper support portion 186a is disposed on the toe side of the upward opening 190 formed on the front side of the continuously extending part 186c. The heel upper support portion 186b is disposed on the heel side of the upward opening 190 formed on the front side of the continuously extending part 186c. The upward opening 190 is located between the toe upper support portion 186a and the heel upper support portion 186b. The back-side end portion of the toe upper support portion 186a is continuous with the continuously extending part 186c. The back-side end portion of the heel upper support portion 186b is continuous with the continuously extending part 186c. The toe upper support portion 186a extends from the toe-side support portion 182 and supports the toe-side end portion of the weight member wt1 from the upper side. The heel upper support portion 186b extends from the heel-side support portion 184 and supports the heel-side end portion of the weight member wt1 from the upper side. Alternatively, the head does not necessarily have to include the toe upper support portion 186a or the heel upper support portion 186b.

[0136] FIG. 34 is an exploded perspective view of a head 400 according to a fourth embodiment. The head 400 includes a cover member 192. Except for the presence of the cover member 192, the head 400 has the same configuration as the head 100 of the first embodiment.

[0137] The cover member 192 covers the upper side of the weight member wt1. Of the upper surface 162 of the weight member wt1, a portion exposed to the cavity space SP by the upward opening 190 is covered by the cover member 192. The cover member 192 covers the weight member wt1 such that the weight member wt1 is not visible from the outside of the head 400. The upper surface 192a of the cover member 192 is exposed to the cavity space SP. The cover member 192 may be fixed to either the weight member wt1 or the head body 120.

[0138] A plate-shaped member may be used as the cover member 192, for example. A badge may be used as the cover member 192, for example. Examples of the material of the cover member 192 include resins, metals, and combinations thereof. From the viewpoint of not impairing the advantageous effects brought about by the upward opening 190, the specific gravity of the cover member 192 is preferably lower than the specific gravity of the head body 120. From this viewpoint, the specific gravity of the cover member 192 is preferably less than or equal to 3.0, more preferably less than or equal to 2.0, and still more preferably less than or equal to 1.5. Considering the availability of materials, the specific gravity of the cover member 192 is preferably greater than or equal to 0.8, more preferably greater than or equal to 0.9, and still more preferably greater than or equal to 1.0.

[0139] FIG. 35 is a cross-sectional view of a head 500 according to a fifth embodiment. FIG. 35 is a cross-sectional view taken at the position of the above-described line D-D. In the head 500, the weight member receiving portion h1 forms a through hole that penetrates through the head body 120. However, a wall that defines the through hole further has an upward opening 190 formed by an absence of a portion of material in the wall, in addition to the openings of the through hole. The weight member wt1 is exposed to the outside of the head 500 on the sole side and / or the back side. The head 500 has the same configuration as the head 100, except for the configurations of the weight member receiving portion h1 and the weight member wt1.

[0140] The weight member receiving portion h1 forms the through hole that is open toward both the face side and the back side. The weight member wt1 is inserted into the weight member receiving portion h1 from the face side. The weight member wt1 includes an exposed surface 194 that forms a part of the outer surface of the head 500. The exposed surface 194 forms a part of the sole surface 104a and / or a part of the back surface 116.

[0141] The weight member receiving portion h1 has a structure that prevents the weight member wt1 from passing through the weight member receiving portion h1 from the face side to the back side. When the weight member wt1 is inserted into the weight member receiving portion h1 from the face side, the weight member wt1 is retained by the weight member receiving portion h1 at a predetermined position in the face-back direction. The weight member receiving portion h1 includes a body tapered portion 196 that becomes narrower toward the back side. The body tapered portion 196 includes a first taper surface 196a and a second taper surface 196b that are disposed opposite each other, and the distance (shortest distance) between the first taper surface 196a and the second taper surface 196b decreases toward the back side. The weight member wt1 includes a taper abutment surface 198 that abuts the body tapered portion 196. The taper abutment surface 198 includes a first surface 198a and a second surface 198b. The distance (shortest distance) between the first surface 198a and the second surface 198b decreases toward the back side. The first surface 198a abuts the first taper surface 196a. The second surface 198b abuts the second taper surface 196b. As described above, the weight member receiving portion h1 may penetrate through the head body 120.

[0142] FIG. 36A is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 100 of the first embodiment. FIG. 36B is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 200 of the second embodiment. FIG. 36C is a perspective view of the head body 120 to which the weight member wt1 is fixed in the head 300 of the third embodiment. As described above, the weight member wt1 is fixed by the joint portion 170 in each embodiment. The joint portion 170 is the welded portion 172. The welded portion 172 is indicated by a bold solid line in FIG. 36A, FIG. 36B and FIG. 36C. In all embodiments, the welded portion 172 is disposed only on the periphery of the front surface 160 of the weight member wt1. In the first embodiment (FIG. 36A), the upward opening 190 penetrates through the upper support portion 186 from its front end to its rear end. In the first embodiment, the welded portion 172 is disposed around the front surface 160, excluding the region where the upward opening 190 is located. The welded portion 172 extends parallel to the toe upper support portion 186a, the toe-side support portion 182, the lower support portion 180, the heel-side support portion 184, and the heel upper support portion 186b. This holds true for the third embodiment (FIG. 36C). In the third embodiment (FIG. 36C), the upward opening 190 is located on the face side of the upper support portion 186. Also in the third embodiment, the welded portion 172 is disposed around the front surface 160, excluding the region where the upward opening 190 is located. The welded portion 172 extends parallel to the toe upper support portion 186a, the toe-side support portion 182, the lower support portion 180, the heel-side support portion 184, and the heel upper support portion 186b.

[0143] In the second embodiment (FIG. 36B), the upward opening 190 is located on the back side of the upper support portion 186. The upward opening 190 is not present on the face side of the weight member wt1 in the second embodiment. In the second embodiment, the face-side opening (opening for receiving the weight member wt1) of the weight member receiving portion h1 is a fully circumferential opening. The term “fully circumferential opening” refers to an opening defined by a continuous peripheral edge extending around its entire circumference. The welded portion 172 in the second embodiment is disposed around the entire circumference of the opening.

[0144] In all embodiments, the process for forming the joint portion 170 (welded portion 172) is carried out in a state where the face member 122 is not fixed to the head body 120. When the face member 122 is not fixed, the weight member receiving portion h1 is open toward the front side. This facilitates joining operations.

[0145] The above-shown embodiments exhibit the following advantageous effects.

[0146] In the first through fifth embodiments, the upward opening 190 is formed. The presence of the upward opening 190 can reduce the weight of the weight member receiving portion h1 on the upper side of the weight member wt1. This weight reduction can lower the position of the center of gravity of the head. The weight saved by the upward opening 190 can be allocated to other part(s), which can increase design flexibility for weight distribution of the head body 120. Allocating the saved weight to a lower-side part of the head body 120 can further lower the position of the center of gravity of the head. Allocating the saved weight to a toe-side part and / or a heel-side part of the head body 120 can increase the moment of inertia of the head.

[0147] The head body 120 including the weight member receiving portion h1 has a complicated shape. The head body 120 is often produced by casting. When the head body 120 is produced by casting, the wall constituting the weight member receiving portion h1 is required to have a wall thickness of greater than or equal to 2.5 mm to ensure castability. Because of this wall thickness, the weight member receiving portion h1 is required to have a large weight. In addition, increasing the dimensions of the weight member wt1 also increases the dimensions of the weight member receiving portion h1, which can further increase the weight of the wall in the upper part of the weight member receiving portion h1. The increased weight of the weight member receiving portion h1 can diminish the design advantage in the center of gravity of the head achieved through the weight member wt1. The wall of the upper part of the weight member receiving portion h1 is positioned on the upper side relative to the weight member wt1, and thus contributes less to lowering the position of the center of gravity of the head. The upward opening 190 can reduce the weight allocated to the portion located on the upper side relative to the weight member wt1, and can further lower the center of gravity of the head. The upward opening 190 can also effectively provide the above-mentioned saved weight. This can further enhance the effect of lowering the center of gravity brought about by the weight member wt1. This can also improve the flexibility of designing both the center of gravity of the head and weight distribution.

[0148] In the first through fifth embodiments, the upper support portion 186 is disposed in a region where the upward opening 190 is not present. Accordingly, the weight member wt1 cannot be removed upward from the weight member receiving portion h1.

[0149] In the first, fourth and fifth embodiments, the upward opening 190 penetrates through the upper support portion 186 in the face-back direction (see FIG. 36A). This structure can enlarge the area of the upward opening 190, thereby further reducing the weight of the upper support portion 186. Since the toe upper support portion 186a and the heel upper support portion 186b are disposed on both sides of the weight member wt1, the weight member wt1 cannot be removed upward from the weight member receiving portion h1.

[0150] In the second and third embodiments, the upper support portion 186 includes the continuously extending part 186c (see FIG. 36B and FIG. 36C). Accordingly, the reliability of fixation of the weight member wt1 is further enhanced. In the second embodiment, the joint portion 170 (welded portion 172) is disposed around the entire circumference of the weight member wt1. This structure further enhances the reliability of fixation of the weight member wt1. In the third embodiment, the continuously extending part 186c covers the rear edge part of the weight member wt1 from the upper side (see FIG. 30 and FIG. 31). The rear edge part of the weight member wt1 is not visible from the outside of the head 300. A gap between the rear edge part of the weight member wt1 and the head body 120 is not visible, either. This configuration can improve the appearance of the head 300.

[0151] In the fourth embodiment, the portion of the weight member wt1 exposed by the upward opening 190 is covered by the cover member 192. The weight member wt1 is not visible from the outside of the head 400. This configuration can improve the appearance of the head 400.

[0152] In the first through fifth embodiments, the weight member wt1 is inserted into the weight member receiving portion h1 from the face side, and is disposed at a position at which the weight member wt1 cannot move further backward. Accordingly, the weight member wt1 is securely fixed, even though the joint portion 170 (welded portion 172) is located only on the face side of the weight member wt1.

[0153] A double-pointed arrow D1 in FIG. 2 indicates the width of the weight member wt1. The width D1 is measured in the toe-heel direction. There is no limitation on the width D1. From the viewpoint of lowering the center of gravity of the head, the width D1 can be greater than or equal to 20 mm, further can be greater than or equal to 30 mm, and still further can be greater than or equal to 40 mm. From the viewpoint of dimensional restrictions on the head, the width D1 can be less than or equal to 70 mm, further can be less than or equal to 65 mm, and still further can be less than or equal to 60 mm.

[0154] A double-pointed arrow D2 in FIG. 2 indicates the width of the upward opening 190. The width D2 is measured in the toe-heel direction. There is no limitation on the width D2. From the viewpoint of increasing the above-mentioned saved weight, the ratio of the width D2 to the width D1 is preferably greater than or equal to 70%, more preferably greater than or equal to 75%, still more preferably greater than or equal to 80%, and yet more preferably greater than or equal to 85%. From the viewpoint of ensuring sufficient width for the toe upper support portion 186a and the heel upper support portion 186b, the ratio of the width D2 to the width D1 is preferably less than or equal to 95%, more preferably less than or equal to 92%, and still more preferably less than or equal to 90%.

[0155] The sum of the width (measured in the toe-heel direction) of the toe upper support portion 186a and the width (measured in the toe-heel direction) of the heel upper support portion 186b is equal to the difference (D1−D2). From the viewpoint of ensuring reliable fixation of the weight member wt1, the ratio of the difference (D1−D2) to the width D1 is preferably greater than or equal to 5%, more preferably greater than or equal to 8%, and still more preferably greater than or equal to 10%. From the viewpoint of ensuring sufficient width D2 of the upward opening 190, the ratio of the difference (D1−D2) to the width D1 is preferably less than or equal to 30%, more preferably less than or equal to 25%, still more preferably less than or equal to 20%, and yet more preferably less than or equal to 15%.

[0156] A double-pointed arrow D3 in FIG. 19 indicates the width of the continuously extending part 186c disposed on the face side. The width D3 is measured in the face-back direction. The width D3 is measured on the upper surface of the continuously extending part 186c. From the viewpoint of the amount of welding material permeated during the welding process, as well as from the viewpoint of preventing deformation during the welding process, the width D3 is preferably greater than or equal to 4 mm, more preferably greater than or equal to 4.5 mm, and still more preferably greater than or equal to 5 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the width D3 is preferably less than or equal to 12 mm, more preferably less than or equal to 10 mm, and still more preferably less than or equal to 8 mm. From the viewpoint of castability, the thickness of the continuously extending part 186c disposed on the face side is preferably greater than or equal to 2.5 mm, more preferably greater than or equal to 2.6 mm, and still more preferably greater than or equal to 2.7 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the thickness of the continuously extending part 186c disposed on the face side is preferably less than or equal to 6.0 mm, more preferably less than or equal to 5.5 mm, and still more preferably less than or equal to 5.0 mm.

[0157] A double-pointed arrow D4 in FIG. 30 indicates the width of the continuously extending part 186c disposed on the back side. The width D4 is measured in the face-back direction. The width D4 is measured on the upper surface of the continuously extending part 186c. From the viewpoint of concealing the rear edge part of the weight member wt1, the width D4 is preferably greater than or equal to 2 mm, more preferably greater than or equal to 2.5 mm, and still more preferably greater than or equal to 3 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the width D4 is preferably less than or equal to 10 mm, more preferably less than or equal to 8 mm, and still more preferably less than or equal to 6 mm. From the viewpoint of castability, the thickness of the continuously extending part 186c disposed on the back side is preferably greater than or equal to 2.5 mm, more preferably greater than or equal to 2.6 mm, and still more preferably greater than or equal to 2.7 mm. From the viewpoint of suppressing the weight of the upper support portion 186, the thickness of the continuously extending part 186c disposed on the back side is preferably less than or equal to 6.0 mm, more preferably less than or equal to 5.5 mm, and still more preferably less than or equal to 5.0 mm.

[0158] In the second embodiment, the continuously extending part 186c is located at the face-most position. In this configuration, the continuously extending part 186c forms a portion of the wall that defines the opening for receiving the weight member receiving portion h1. In the third embodiment, the continuously extending part 186c is located at the back-most position. In this configuration, a back-side portion of the continuously extending part 186c is continuous with another portion (the wall 188, for example) of the head body. In contrast to the second and third embodiments, the continuously extending part 186c may be located at an intermediate position in the face-back direction. In this configuration, the upward opening 190 is formed on both the face side and the back side of the continuously extending part 186c.

[0159] From the viewpoint of lowering the center of gravity of the head, the weight saved by the upward opening 190 is preferably greater than or equal to 5 g, more preferably greater than or equal to 7 g, and still more preferably greater than or equal to 9 g. From the viewpoint of dimensional restrictions on the head, the weight saved by the upward opening 190 is preferably less than or equal to 20 g, more preferably less than or equal to 18 g, and still more preferably less than or equal to 16 g. The saved weight is the amount of weight removed from the upper support portion 186 by the upward opening 190. A part of the weight member wt1 that is exposed to the outside by the upward opening 190 has an area denoted by M (cm2). The thickness of the upper support portion 186 is denoted by t (cm). The specific gravity of the upper support portion 186 is denoted by S. The saved weight (grams) is calculated as M×t×S. As described above, a part of the upper surface 162 of the weight member wt1 is exposed to the cavity space SP. The area of the exposed part is denoted by M. The thickness t is the thickness of the upper support portion 186 in a region where the upward opening 190 is not formed. When the upper support portion 186 does not have a constant thickness, the thickness t is defined as the average thickness of the upper support portion 186. The average thickness can be calculated by dividing the volume of the upper support portion 186 by the area of the upper surface 162 covered by the upper support portion 186.

[0160] From the viewpoint of lowering the center of gravity of the head, the ratio of the saved weight to the head weight is preferably greater than or equal to 2%, more preferably greater than or equal to 2.5%, still more preferably greater than or equal to 3%, and yet more preferably greater than or equal to 3.5%. Considering the dimensional limitations of the weight member receiving portion h1, the ratio of the saved weight to the head weight is preferably less than or equal to 10%, more preferably less than or equal to 9%, and still more preferably less than or equal to 8%.

[0161] From the viewpoint of lowering the center of gravity of the head, the center of gravity of the weight member wt1 is preferably located on the lower side relative to the center of gravity of the head. From the viewpoint of a lateral moment of inertia, the center of gravity of the weight member wt1 is preferably located on the toe side relative to the face center Fc. In this configuration, the head weight is distributed toward peripheral portions in the toe-heel direction by the weight of the hosel 108 located on the heel side and the weight of the weight member wt1 located on the toe side. The lateral MI refers to the moment of inertia of a head about an axis that passes through the center of gravity of the head and extends in the up-down direction.

[0162] The method of producing the heads 100, 200, 300, 400, and 500 described in the above embodiments can include the following steps (1) to (3).

[0163] (1) A first step of inserting the weight member wt1 into the weight member receiving portion h1 of the head body 120 from the face side, prior to attaching the face member 122 to the head body 120.

[0164] (2) A second step of forming the joint portion 170 (welded portion 172) on the boundary between the weight member wt1 and the weight member receiving portion h1 on the face side of the weight member wt1 in the assembly produced during the first step.

[0165] (3) A third step of attaching the face member 122 to the head body 120 that has been processed in the second step.

[0166] The following clauses are part of the invention included in the present disclosure.[Clause 1]

[0167] A golf club head including a striking face and a sole surface, wherein

[0168] the golf club head further includes:

[0169] a head body that includes a face opening and a weight member receiving portion;

[0170] a face member that covers the face opening and forms at least a part of the striking face;

[0171] a weight member that is inserted into the weight member receiving portion from a face side and is fixed to the weight member receiving portion; and

[0172] a joint portion formed on a boundary between the weight member receiving portion and the weight member, and

[0173] the weight member receiving portion includes:

[0174] a lower support portion that supports a lower side of the weight member;

[0175] a toe-side support portion that supports a toe side of the weight member;

[0176] a heel-side support portion that supports a heel side of the weight member;

[0177] an upper support portion that supports an upper side of the weight member; and

[0178] an upward opening formed by an absence of a portion of material in the upper support portion.[Clause 2]

[0179] The golf club head according to clause 1, wherein

[0180] the upper support portion includes a toe upper support portion that extends from the toe-side support portion and supports a toe-side end of the weight member from an upper side, and a heel upper support portion that extends from the heel-side support portion and supports a heel-side end of the weight member from the upper side, and

[0181] the upward opening is located between the toe upper support portion and the heel upper support portion.[Clause 3]

[0182] The golf club head according to clause 1 or 2, wherein

[0183] the upward opening penetrates through the upper support portion in a face-back direction.[Clause 4]

[0184] The golf club head according to clause 1 or 2, wherein

[0185] the upper support portion includes a continuously extending part that extends continuously from the toe-side support portion to the heel-side support portion, and the upward opening is formed on a face side and / or a back side of the continuously extending part.[Clause 5]

[0186] The golf club head according to any one of clauses 1 to 4, wherein

[0187] the face member includes a front surface that forms at least a part of the striking face, and a rear surface that is a surface opposite to the front surface,

[0188] the weight member includes a front surface located on the face side, and

[0189] the rear surface of the face member and the front surface of the weight member face each other across a space.LIST OF REFERENCE SYMBOLS100, 200, 300, 400, 500 Golf club head

[0191] 102 Striking face

[0192] 104 Sole portion

[0193] 104a Sole surface

[0194] 108 Hosel

[0195] 114 Back cavity

[0196] 116 Back surface

[0197] 120 Head body

[0198] 122 Face member

[0199] 134 Face opening

[0200] 150 Front surface of the face member

[0201] 152 Rear surface of the face member

[0202] 170 Joint portion

[0203] 172 Welded portion

[0204] 180 Lower support portion of the weight member receiving portion

[0205] 182 Toe-side support portion of the weight member receiving portion

[0206] 184 Heel-side support portion of the weight member receiving portion

[0207] 186 Upper support portion of the weight member receiving portion

[0208] 186a Toe upper support portion

[0209] 186b Heel upper support portion

[0210] 186c Continuously extending part

[0211] 190 Upward opening

[0212] 192 Cover member

[0213] Fc Face center

[0214] SP Cavity space

[0215] SP1 Pocket space

[0216] h1 Weight member receiving portion

[0217] wt1 Weight member

[0218] gv Score lines

[0219] gv1 Longest score line

[0220] Pt Toe reference position

[0221] Pc Score line center position

[0222] Ph Heel reference position

[0223] Le Leading edge

[0224] Te Trailing edge

[0225] The foregoing descriptions are merely illustrative, and various modifications may be made without departing from the principles of the present disclosure.

[0226] The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The use of the terms “a”, “an”, “the”, and similar referents in the context of throughout this disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. As used throughout this disclosure, the word “may” is used in a permissive sense (i.e., meaning “having the potential to”), rather than the mandatory sense (i.e., meaning “must”). Similarly, as used throughout this disclosure, the terms “comprising,”“having,”“including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted.

Examples

first embodiment

[0061]FIG. 1 shows a head 100 as viewed from the front of its striking face 102. FIG. 2 is the same drawing as FIG. 1, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 3 is a perspective view of the head 100 as viewed from the back side.

[0062]The head 100 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The sole surface 104a is the outer surface of the sole portion 104. The hosel 108 has a hosel hole 110. The hosel hole 110 has a center line Z. A shaft (not shown in the drawings) is attached to the hosel hole 110. The center line Z coincides with the shaft axis line. The striking face 102 and the sole surface 104a constitute a part of the outer surface of the head 100.

[0063]As shown in FIG. 3, the head 100 includes a leading edge Le and a trailing edge Te. The trailing edge Te is the rear edge of the sole surface 10...

second embodiment

[0106]FIG. 12 shows a head 200 as viewed from the front of its striking face 102. FIG. 13 is the same drawing as FIG. 12, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 14 is a perspective view of the head 200 as viewed from the back side.

[0107]The head 200 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 has a hosel hole 110. The head 200 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 14, the head 200 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 200. The head 200 includes a back surface 116.

[0108]FIG. 15 is an exploded perspective view of the head 200. In FIG. 15, the weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 15, the score lines gv on the f...

third embodiment

[0121]FIG. 23 shows a head 300 as viewed from the front of its striking face 102. FIG. 24 is the same drawing as FIG. 23, except that dashed lines are additionally used to illustrate the contours of a head body 120 concealed by a face member 122. FIG. 25 is a perspective view of the head 300 as viewed from the back side.

[0122]The head 300 includes the striking face 102, a sole portion 104, a top blade 106, and a hosel 108. The sole portion 104 includes a sole surface 104a. The hosel 108 includes a hosel hole 110. The head 300 is an iron type golf club head. The striking face 102 is a flat surface. As shown in FIG. 25, the head 300 has a back cavity 114. The back cavity 114 forms a cavity space SP on the back side of the head 300. The head 300 includes a back surface 116.

[0123]FIG. 26 is an exploded perspective view of the head 300. In FIG. 26, a weight member wt1 fixed to the head body 120 is indicated by virtual lines (dash-dot-dot-dash lines). In FIG. 26, the score lines gv on th...

Claims

1. A golf club head comprising a striking face and a sole surface, whereinthe golf club head further includes:a head body that includes a face opening and a weight member receiving portion;a face member that covers the face opening and forms at least a part of the striking face;a weight member that is inserted into the weight member receiving portion from a face side and is fixed to the weight member receiving portion; anda joint portion formed on a boundary between the weight member receiving portion and the weight member, andthe weight member receiving portion includes:a lower support portion that supports a lower side of the weight member;a toe-side support portion that supports a toe side of the weight member;a heel-side support portion that supports a heel side of the weight member;an upper support portion that supports an upper side of the weight member; andan upward opening formed by an absence of a portion of material in the upper support portion.

2. The golf club head according to claim 1, whereinthe upper support portion includes a toe upper support portion that extends from the toe-side support portion and supports a toe-side end of the weight member from an upper side, and a heel upper support portion that extends from the heel-side support portion and supports a heel-side end of the weight member from the upper side, andthe upward opening is located between the toe upper support portion and the heel upper support portion.

3. The golf club head according to claim 2, whereinthe upward opening penetrates through the upper support portion in a face-back direction.

4. The golf club head according to claim 1, whereinthe upper support portion includes a continuously extending part that extends continuously from the toe-side support portion to the heel-side support portion, andthe upward opening is formed on a face side and / or a back side of the continuously extending part.

5. The golf club head according to claim 1, whereinthe face member includes a front surface that forms at least a part of the striking face, and a rear surface that is a surface opposite to the front surface,the weight member includes a front surface located on the face side, andthe rear surface of the face member and the front surface of the weight member face each other across a space.

6. The golf club head according to claim 1, whereinthe golf club head is a cavity back iron head that includes a back cavity, andin a region where the upward opening is located, an upper surface of the weight member is exposed to a cavity space that is an internal empty space of the back cavity.

7. The golf club head according to claim 1, whereina saved weight produced by the upward opening is greater than or equal to 5 g and less than or equal to 20 g, the saved weight (grams) being calculated as M×t×S, whereM is an area (cm2) of a surface of a part of the weight member that is exposed to an outside by the upward opening, t is a thickness (cm) of the upper support portion, and S is a specific gravity of the upper support portion.

8. The golf club head according to claim 1, whereina ratio of a saved weight produced by the upward opening to a weight of the golf club head is greater than or equal to 2% and less than or equal to 10%, the saved weight (grams) being calculated as M×t×S, whereM is an area (cm2) of a surface of a part of the weight member that is exposed to an outside by the upward opening, t is a thickness (cm) of the upper support portion, and S is a specific gravity of the upper support portion.

9. The golf club head according to claim 1, whereina width of the weight member measured in a toe-heel direction is denoted by D1,a width of the upward opening measured in the toe-heel direction is denoted by D2, anda ratio of the width D2 to the width D1 is greater than or equal to 70% and less than or equal to 95%.

10. A golf club head comprising a striking face and a sole surface, whereinthe golf club head further includes:a head body that includes a face opening and a weight member receiving portion;a face member that covers the face opening and forms at least a part of the striking face;a weight member that is inserted into the weight member receiving portion from a face side and is fixed to the weight member receiving portion; anda joint portion formed on a boundary between the weight member receiving portion and the weight member, andthe weight member receiving portion includes:a lower support portion that supports a lower side of the weight member;a toe-side support portion that supports a toe side of the weight member;a heel-side support portion that supports a heel side of the weight member;an upper support portion that supports an upper side of the weight member; andan upward opening that opens the weight member receiving portion on its upper side.

11. The golf club head according to claim 10, whereinthe upper support portion includes a toe upper support portion that extends from the toe-side support portion and supports a toe-side end of the weight member from an upper side, and a heel upper support portion that extends from the heel-side support portion and supports a heel-side end of the weight member from the upper side, andthe upward opening is located between the toe upper support portion and the heel upper support portion.

12. The golf club head according to claim 11, whereinthe upward opening penetrates through the upper support portion in a face-back direction.

13. The golf club head according to claim 10, whereinthe upper support portion includes a continuously extending part that extends continuously from the toe-side support portion to the heel-side support portion, andthe upward opening is formed on a face side and / or a back side of the continuously extending part.

14. The golf club head according to claim 10, whereinthe face member includes a front surface that forms at least a part of the striking face, and a rear surface that is a surface opposite to the front surface,the weight member includes a front surface located on the face side, andthe rear surface of the face member and the front surface of the weight member face each other across a space.

15. The golf club head according to claim 10, whereinthe golf club head is a cavity back iron head that includes a back cavity, andin a region where the upward opening is located, an upper surface of the weight member is exposed to a cavity space that is an internal empty space of the back cavity.

16. The golf club head according to claim 10, whereina saved weight produced by the upward opening is greater than or equal to 5 g and less than or equal to 20 g, the saved weight (grams) being calculated as M×t×S, whereM is an area (cm2) of a surface of a part of the weight member that is exposed to an outside by the upward opening, t is a thickness (cm) of the upper support portion, and S is a specific gravity of the upper support portion.

17. The golf club head according to claim 10, whereina ratio of a saved weight produced by the upward opening to a weight of the golf club head is greater than or equal to 2% and less than or equal to 10%, the saved weight (grams) being calculated as M×t×S, whereM is an area (cm2) of a surface of a part of the weight member that is exposed to an outside by the upward opening, t is a thickness (cm) of the upper support portion, and S is a specific gravity of the upper support portion.

18. The golf club head according to claim 10, whereina width of the weight member measured in a toe-heel direction is denoted by D1,a width of the upward opening measured in the toe-heel direction is denoted by D2, anda ratio of the width D2 to the width D1 is greater than or equal to 70% and less than or equal to 95%.

19. A golf club head comprising a striking face and a sole surface, whereinthe golf club head further includes:a head body that includes a face opening and a weight member receiving portion;a face member that covers the face opening and forms at least a part of the striking face;a weight member that is inserted into the weight member receiving portion from a face side and is fixed to the weight member receiving portion; anda joint portion formed on a boundary between the weight member receiving portion and the weight member, andthe weight member receiving portion includes:a lower support portion that supports a lower side of the weight member;an upper support portion that supports an upper side of the weight member; andan upward opening formed by an absence of a portion of material in the upper support portion.

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