Golf club head

Abstract

To provide a novel fixing structure in a golf club head including an adjustment member that is fixed to a head outer surface.SOLUTION: A head 100 includes at least one adjustment member 120 detachably fixed to a head outer surface 102a while holding a body wall part 114. A head body 102 includes at least one opening 154 that penetrates the body wall part 114. The adjustment member 120 includes an inner part 122, an outer part 124, and a rotation connection part 126. A rotational position of the inner part 122 has a passage position that may pass through the opening 154 and a non-passage position that cannot pass through the opening 154. In the non-passage position, an inner surface abutment part 152 of the inner part 122 abuts on a head inner surface 102b. The head body 102 or the adjustment member 120 includes a corotation prevention part for preventing the inner part 122 in the non-passage position from co-rotating with the rotation connection part 126.SELECTED DRAWING: Figure 3

Description

Technical Field

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

Background Art

[0002] A golf club head with a weight member attached is known. Japanese Patent Application Laid-Open No. 2016-55109 discloses a golf club head including an attachment hole portion provided in a sole portion and a weight member that can be inserted into the attachment hole portion. In this head, by rotating the weight member in the clockwise direction, the weight member reaches a locked position where it cannot be removed from the attachment hole portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Adjustment members fixed to the outer surface of the head can be used for various purposes. For example, by attaching or replacing this adjustment member, it is possible to adjust various characteristics of the head. Examples of the characteristics of the head that can be adjusted include the aerodynamic characteristics of the head, the center of gravity position of the head, the shape of the head, and the like.

[0005] The inventor has found a new fixing structure for the adjustment member. This fixing structure can sandwich the head body and enables retrofitting of the adjustment member.

[0006] One object of the present invention is to provide a new fixing structure in a golf club head having an adjustment member fixed to the outer surface of the head.

Means for Solving the Problems

[0007] In one embodiment, the golf club head comprises a head body having a main body wall portion that forms the inner surface and outer surface of the head, and at least one adjustment member detachably fixed to the outer surface of the head in a manner that sandwiches the main body wall portion. The head body has at least one opening that penetrates the main body wall portion. The adjustment member has an inner portion having an inner surface contact portion that abuts against the inner surface of the head, an outer portion having an outer surface contact portion that abuts against the outer surface of the head, and a rotatable connecting portion that connects the inner portion and the outer portion. The rotational position of the inner portion has a passing position in which it can pass through the opening and a non-passing position in which it cannot pass through the opening. In the non-passing position, the inner surface contact portion abuts against the inner surface of the head. The head body or the adjustment member has a co-rotation prevention portion that prevents the inner portion in the non-passing position from rotating together with the rotatable connecting portion. [Effects of the Invention]

[0008] One aspect of this is that a new fixing structure can be provided for a golf club head having an adjustment member fixed to the outer surface of the head. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view of the golf club head of the first embodiment. [Figure 2] Figure 2 is a perspective view of the head body of the head shown in Figure 1. [Figure 3] Figure 3 is a cross-sectional view along line AA in Figure 1. [Figure 4] Figure 4(a) is a plan view of the outer part of the adjustment member according to the first embodiment, Figure 4(b) is a bottom view of the outer part, and Figure 4(c) is a perspective view of the outer part as seen from the bottom side. [Figure 5] Figure 5(a) is a perspective view of the inner part of the adjustment member according to the first embodiment, Figure 5(b) is a plan view of this inner part, Figure 5(c) is a bottom view of this inner part, and Figure 5(d) is a side view of this inner part. [Figure 6]Figure 6 is a perspective view of an assembly in which the adjustment members according to the first embodiment are assembled. [Figure 7] Figure 7 is a view from the inside of the head showing the process of inserting and fixing the adjustment member according to the first embodiment into the head body. [Figure 8] Figure 8 is a perspective view of the golf club head of the second embodiment. [Figure 9] Figure 9 is a perspective view of the head body in the head of the second embodiment. [Figure 10] Figure 10(a) is a plan view of the outer part of the adjustment member according to the second embodiment, and Figure 10(b) is a perspective view of this outer part as seen from the bottom side. [Figure 11] Figure 11 is a perspective view of an assembly in which the adjustment members according to the second embodiment are assembled. [Figure 12] Figure 12 is a view from the inside of the head showing the process of inserting and fixing the adjustment member according to the second embodiment into the head body. [Figure 13] Figure 13 is a perspective view of the golf club head of the third embodiment. [Figure 14] Figure 14 is a perspective view of the head body in the head of the third embodiment. [Figure 15] Figure 15(a) is a plan view of the outer part of the adjustment member according to the third embodiment, Figure 15(b) is a bottom view of this outer part, and Figure 15(c) is a perspective view of this outer part as seen from the bottom side. [Figure 16] Figure 16(a) is a perspective view of the inner part of the adjustment member according to the third embodiment, Figure 16(b) is a plan view of this inner part, Figure 16(c) is a bottom view of this inner part, and Figure 16(d) is a side view of this inner part. [Figure 17] Figure 17 is a perspective view of the assembly in which the adjustment members according to the third embodiment are assembled. [Figure 18] Figure 18 is a view from inside the head showing the process of inserting and fixing the adjustment member according to the third embodiment into the head body. For ease of understanding, in this figure, two internal components of the inner part are distinguished by hatching. [Figure 19]FIG. 19(a) is a perspective view of a head body according to the fourth embodiment, FIG. 19(b) is a perspective view of an outer portion of an adjustment member according to the fourth embodiment, and FIG. 19(c) is a perspective view of the head according to the fourth embodiment. [Figure 20] FIG. 20(a) is a perspective view of a head body according to the fifth embodiment, FIG. 20(b) is a perspective view of an outer portion of an adjustment member according to the fifth embodiment, and FIG. 20(c) is a perspective view of the head according to the fifth embodiment. [Figure 21] FIG. 21(a) is a perspective view of a head body according to the sixth embodiment, FIG. 21(b) is a perspective view of an outer portion of an adjustment member according to the sixth embodiment, and FIGS. 21(c) and 21(d) are perspective views of the head according to the sixth embodiment. [Figure 22] FIG. 22(a) is a perspective view of a head body according to the seventh embodiment, FIG. 22(b) is a bottom view of an outer portion of an adjustment member according to the seventh embodiment, and FIG. 22(c) is a perspective view of the head according to the seventh embodiment. [Figure 23] FIG. 23(a) is a perspective view of a head body according to the eighth embodiment, FIG. 23(b) is a bottom view of an outer portion of an adjustment member according to the eighth embodiment, and FIG. 23(c) is a perspective view of the head according to the eighth embodiment. [Figure 24] FIG. 24(a) is a perspective view of the head according to the ninth embodiment as viewed from the crown side, and FIG. 24(b) is a perspective view of this head as viewed from the sole side. [Figure 25] FIG. 25(a) is a cross-sectional view of the vicinity of an adjustment member in the head according to the tenth embodiment, and FIG. 25(b) is a cross-sectional view of the vicinity of an adjustment member in a modified head according to the tenth embodiment. [Figure 26] FIG. 26 is a cross-sectional view of the vicinity of an adjustment member in the head according to the eleventh embodiment. [Figure 27] FIG. 27 is a cross-sectional view of the vicinity of an adjustment member in the head according to the twelfth embodiment. [Figure 28] FIG. 28 is a cross-sectional view of the vicinity of an adjustment member in the head according to the thirteenth embodiment. [Figure 29] FIG. 29 is a cross-sectional view of the vicinity of an adjustment member in the head according to the fourteenth embodiment. [Figure 30]Figure 30 is a cross-sectional view of the head near the adjustment member in the 15th embodiment. [Figure 31] Figure 31(a) is a perspective view of the head body according to the 16th embodiment, Figure 31(b) is a bottom view of the outer part of the adjustment member according to the 16th embodiment, and Figure 31(c) is a perspective view of the head according to the 16th embodiment. [Figure 32] Figure 32 is a conceptual diagram illustrating the reference state. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below, with reference to drawings as appropriate.

[0011] In this application, the reference state, reference vertical plane, toe-heel direction, face-back direction, vertical direction, and face center are defined.

[0012] The reference state is defined as the state in which the club head is placed on the ground plane HP at a predetermined lie angle. As shown in Figure 32, in this reference state, the shaft axis Z is contained within the plane VP perpendicular to the ground plane HP. The shaft axis Z is the center line of the shaft. Typically, the shaft axis Z coincides with the center line of the hosel hole. The plane VP is defined as the reference vertical plane. The predetermined lie angle is listed, for example, in the product catalog.

[0013] Furthermore, clubs equipped with a variable mechanism that allows adjustment of loft angle, lie angle, and face angle by the rotational position of a sleeve or similar component located at the tip of the shaft are known. In the head used in such a club, under the above-mentioned standard conditions, all adjustment items are set to neutral, and the shaft axis Z is determined. Neutral means the center of the adjustment range.

[0014] In this standard state, the face angle is considered to be 0 degrees. That is, in a plan view from above, the normal to the face center of the striking face is considered to be perpendicular to the toe-heel direction. The definitions of the face center and the toe-heel direction are described below.

[0015] In this application, the toe-heel direction is the direction of the intersection line NL between the reference vertical plane VP and the ground plane HP (see Figure 32).

[0016] In this application, the face-back direction is the direction perpendicular to the toe-heel direction and parallel to the ground plane HP. The face side in the face-back direction is also simply referred to as the "face side." The back side in the face-back direction is also simply referred to as the "back side."

[0017] In this application, the vertical direction is the direction perpendicular to the toe-heel direction and perpendicular to the face-back direction. In other words, in this application, the vertical direction is the direction perpendicular to the ground plane HP.

[0018] In this application, the face center is determined as follows: First, an arbitrary point Pr is selected near the approximate center of the striking face in the vertical and toe-heel directions. Next, a plane is determined that passes through this point Pr, extends along the normal direction of the striking face at point Pr, and is parallel to the toe-heel direction. A line is drawn between this plane and the striking face, and its midpoint Px is determined. Next, a plane is determined that passes through this midpoint Px, extends along the normal direction of the striking face at point Px, and is parallel to the vertical direction. A line is drawn between this plane and the striking face, and its midpoint Py is determined. Next, a plane is determined that passes through this midpoint Py, extends along the normal direction of the striking face at point Py, and is parallel to the toe-heel direction. A line is drawn between this plane and the striking face, and its midpoint Px is newly determined. Next, a plane is determined that passes through this new midpoint Px, extends along the normal direction of the striking face at point Px, and is parallel to the vertical direction. A line is drawn at the intersection of this plane and the hitting face, and the midpoint Py is newly determined. This process is repeated to sequentially determine Px and Py. In the repetition of this process, the new position Py (the last position Py) at which the distance between the new midpoint Py and the immediately preceding midpoint Py becomes 0.5 mm or less is the face center.

[0019] Multiple embodiments are described below. In the following description, the same reference numerals are used when the same components are used in different embodiments.

[0020] Figure 1 is a perspective view of the head 100 of the first embodiment. Figure 2 is a perspective view of the head body 102. Figure 3 is a cross-sectional view along line AA in Figure 1.

[0021] The head 100 has a face portion 104, a crown portion 106, a sole portion 108, and a hosel portion 110. The hosel portion 110 has a hosel hole 112. The head 100 has a hollow structure. The head body 102 has a head outer surface 102a and a head inner surface 102b. The head outer surface 102a includes the crown outer surface 106a. The head inner surface 102b includes the crown inner surface 106b. The head inner surface 102b faces the hollow portion k1 of the head 100.

[0022] The head body 102 has a body wall portion 114. The body wall portion 114 constitutes the outer shell of the head body 102. The outer surface of the body wall portion 114 is the head outer surface 102a. The inner surface of the body wall portion 114 is the head inner surface 102b.

[0023] Head 100 is a wood-type head. Head 100 is a driver head. The type of head is not limited. Head 100 may be a hybrid-type head, an iron-type head, or a putter-type head.

[0024] The head 100 has an adjustment member 120. The adjustment member 120 is attached to the head body 102. The adjustment member 120 is attached to the body wall 114. The adjustment member 120 is attached to the outer surface 102a of the head. The adjustment member 120 is fixed in a detachable manner. The adjustment member 120 is fixed to the crown portion 106. The adjustment member 120 is attached to the heel side of the face center. The position of the adjustment member 120 is not limited.

[0025] The adjustment member 120 has an inner portion 122, an outer portion 124, and a rotatable connecting portion 126. In this embodiment, the rotatable connecting portion 126 is a screw. The rotatable connecting portion 126 has a head 127 and a threaded portion 128. The threaded portion 128 forms a male thread. The outer portion 124 is located outside the head 100 relative to the inner portion 122. The outer portion 124 rotatably holds the rotatable connecting portion 126. The inner portion 122 is screwed into the rotatable connecting portion 126. By tightening the rotatable connecting portion 126, the inner portion 122 is pulled towards the outer portion 124, and the head body 102 is sandwiched between the inner portion 122 and the outer portion 124. As a result, the adjustment member 120 is fixed.

[0026] The adjustment member 120 is a separate component from the head body 102. The inner part 122 is a separate component from the outer part 124 and the rotating connecting part 126. The outer part 124 is a separate component from the inner part 122 and the rotating connecting part 126. As will be described later, the outer part 124 and the rotating connecting part 126 may be a single unit.

[0027] Figure 4(a) is a plan view of the outer part 124, Figure 4(b) is a bottom view of the outer part 124, and Figure 4(c) is a perspective view of the outer part 124. Figure 4(c) is a perspective view of the outer part 124 as seen from the bottom side.

[0028] The outer portion 124 has an upper surface 130 and a bottom surface 132. In the fixed state of the adjustment member 120, the upper surface 130 is exposed. In the fixed state of the adjustment member 120, the bottom surface 132 faces the outer surface 102a of the head.

[0029] The outer portion 124 has a boss portion 134. The boss portion 134 has a cylindrical portion 138 and a through hole 140 formed at the bottom of the cylindrical portion 138. The head 127 of the rotatable connecting portion 126 is housed in the cylindrical portion 138. The through hole 140 has an inner diameter that the head 127 cannot pass through. The boss portion 134 protrudes from the bottom surface 132 of the outer portion 124 (see Figure 4(c)). The threaded portion 128 of the rotatable connecting portion 126 is inserted through the through hole 140. The through hole 140 does not screw into the threaded portion 128. The boss portion 134 holds the rotatable connecting portion 126 so that it can rotate freely.

[0030] The outer portion 124 has an outer contact portion 136. When the adjustment member 120 is fixed, the outer contact portion 136 contacts the outer surface 102a of the head. In this embodiment, the portion other than the boss portion 134 is the outer contact portion 136.

[0031] Figure 5(a) is a perspective view of the inner part 122, Figure 5(b) is a plan view of the inner part 122, Figure 5(c) is a bottom view of the inner part 122, and Figure 5(d) is a side view of the inner part 122.

[0032] The inner portion 122 has a base portion 142 and an outwardly extending portion 144. The base portion 142 has a cylindrical portion 146, a bottom portion 148, and a screw hole 150. The outwardly extending portion 144 extends outward from the outer edge (cylindrical portion 146) of the base portion 142. The outwardly extending portion 144 is provided at multiple locations (2 locations) in the circumferential direction of the base portion 142. The screw hole 150 forms an internal thread. The screw hole 150 is screwed into the threaded portion 128.

[0033] The inner portion 122 has an inner surface contact portion 152. When the adjustment member 120 is fixed, the inner surface contact portion 152 contacts the inner surface 102b of the head. In this embodiment, the cylindrical portion 146 (upper end surface) and the outwardly extending portion 144 are the inner surface contact portion 152.

[0034] As shown in Figure 2, an opening 154 is formed in the main body wall 114 of the head body 102. The opening 154 penetrates the main body wall 114. The shape of the opening 154 corresponds to the shape of the inner part 122 in a plan view (see Figure 5(b)). The opening 154 has a circular part 156 and an outwardly extending part 158 ​​that extends outward from the circular part 156.

[0035] As shown in Figure 3, when the adjustment member 120 is fixed, rotating the pivoting connector 126 pulls the inner part 122, which screws into the threaded part 128, towards the outer part 124. Further tightening the pivoting connector 126 causes the main body wall 114 to be sandwiched between the inner part 122 and the outer part 124, thereby fixing the adjustment member 120. The main body wall 114 is sandwiched between the outer surface contact part 136 of the outer part 124 and the inner surface contact part 152 of the inner part 122.

[0036] The boss portion 134 of the outer portion 124 is inserted into the base portion 142 (cylindrical portion 146) of the inner portion 122. The outer diameter of the boss portion 134 corresponds to the inner diameter of the cylindrical portion 146. The inner portion 122 can rotate around the boss portion 134. Thus, the base portion 142 has a shape that allows the inner portion 122 to rotate around the boss portion 134 when the boss portion 134 is inserted. As will be described later, when the rotating connecting portion 126 is rotated, the inner portion 122 can rotate together with it.

[0037] The diameter of the circular portion 156 of the opening 154 corresponds to the outer diameter of the cylindrical portion 146 of the inner portion 122. As described later, the inner portion 122 can pass through the opening 154.

[0038] Figure 6 is a perspective view of the assembly 160, in which all the components of the adjustment member 120 have been assembled. The relationships between the components in the assembly 160 are the same as those of the adjustment member 120 in its fixed state. The adjustment member 120 is attached to the head body 102 in its assembled state 160. The adjustment member 120 can be retrofitted to the head body 102. The adjustment member 120 can be attached to the head body 102 from the outside. The adjustment member 120 can also be removed from the outside of the head body 102.

[0039] Figure 7 is a diagram illustrating the method of attaching the adjustment member 120. Figure 7 is a view of the head 100 (head body 102) from the inside (hollow portion k1 side).

[0040] The head body 102 has a co-rotation prevention portion 162 on the inner surface 102b of the head (see Figures 7 and 2). The co-rotation prevention portion 162 is a projection that protrudes from the inner surface 102b of the head toward the inside of the head 100. This projection is also called a co-rotation prevention projection. This co-rotation prevention projection is a body projection 164 provided on the body wall portion 114.

[0041] To install the adjustment member 120, first, an assembly 160 (Figure 6) is created. In this assembly 160, a gap is provided between the inner surface contact portion 152 of the inner portion 122 and the outer surface contact portion 136 of the outer portion 124 so that the main body wall portion 114 can be sandwiched between them.

[0042] Next, the inner part 122 of the assembly 160 is inserted into the opening 154 (step St1). During this insertion, the phases of the inner part 122 and the opening 154 are aligned. That is, the rotational position of the inner part 122 is adjusted so that it can pass through the opening 154. The rotational position of the inner part 122 at this time is called the passing position. The top diagram of Figure 7 shows the state in which the inner part 122 has passed through the opening 154, as seen from inside the head 100. At this stage, the inner part 122 is located inside the head body 102.

[0043] Next, the rotating coupling portion 126 is rotated in the fastening direction (step St2). At this time, the inner portion 122 rotates together with the rotating coupling portion 126. As the co-rotation progresses, the outwardly extending portion 144 of the inner portion 122 approaches the main body protrusion 164 (co-rotation prevention portion 162).

[0044] Next, the outwardly extending portion 144 comes into contact with the main body projection portion 164 (anti-rotation portion 162) (step St3). This contact prevents co-rotation. With co-rotation prevented, the rotating connecting portion 126 is further rotated in the fastening direction. This rotation causes the rotating connecting portion 126 to rotate without the inner portion 122 rotating, and screw fastening proceeds. As a result, fastening by the rotating connecting portion 126 is completed, and the fixed state (Figure 3) is achieved.

[0045] When removing the adjustment member 120, the rotating connecting part 126 is rotated in the opposite direction to when it was fastened. At this time, the inner part 122 may rotate together, but it will eventually come into contact with the main body protrusion 164 (anti-rotation part 162), preventing it from rotating together. Thus, the fastening by the rotating connecting part 126 can be loosened. After that, the rotational position of the inner part 122 is adjusted to the passing position, allowing the inner part 122 to pass through the opening 154. As a result, the assembly 160 can be separated from the head body 102, and the adjustment member 120 can be removed.

[0046] In step St2, as the inner portion 122 begins to rotate, the rotational position of the inner portion 122 shifts to a non-passing position where it cannot pass through the opening 154. Even when the outwardly extending portion 144 is in contact with the main body projection 164, the rotational position of the inner portion 122 is a non-passing position. In this embodiment, all rotational positions other than the passing position are non-passing positions. With the inner portion 122 in a non-passing position, the inner portion 122 can come into contact with the inner surface 102b of the head. The inner portion 122 in a non-passing position can sandwich the main body wall 114 between itself and the outer portion 124.

[0047] Figure 8 is a perspective view of the head 200 of the second embodiment. Figure 9 is a perspective view of the head body 202.

[0048] The head 200 has a face portion 204, a crown portion 206, a sole portion 208, and a hosel portion 210. The hosel portion 210 has a hosel hole 212. The head 200 has a hollow structure. The head 200 has an adjustment member 220.

[0049] Figure 10(a) is a plan view of the outer portion 224 used in the adjustment member 220, and Figure 10(b) is a perspective view of the outer portion 224 viewed from the bottom side. Figure 11 is a perspective view of the assembly 260 in which the adjustment member 220 is assembled.

[0050] The adjustment member 220 (assembly 260) has an inner part 122, an outer part 224, and a rotating connecting part 126. The rotating connecting part 126 has a head 127 (see Figure 8) and a threaded part 128 (see Figure 11).

[0051] The outer portion 224 has an upper surface 230 and a bottom surface 232. In the fixed state of the adjustment member 220, the upper surface 230 is exposed. In the fixed state of the adjustment member 220, the bottom surface 232 faces the outer surface of the head (outer surface of the crown). The outer portion 224 has a boss portion 234 (see Figure 10(b)). The boss portion 234 has a cylindrical portion 238 and a through hole 240 formed at the bottom of the cylindrical portion 238. The head 127 of the pivotable connecting portion 126 is housed in the cylindrical portion 238. The through hole 240 has an inner diameter that the head 127 cannot pass through. On the bottom surface 232 of the outer portion 224, the boss portion 234 protrudes (see Figure 10(b)). The threaded portion 128 of the pivotable connecting portion 126 is inserted through the through hole 240. The through hole 240 is not screwed into the threaded portion 128. The boss portion 234 holds the rotatable connecting portion 126 so that it can rotate freely.

[0052] The outer portion 224 has an outer surface contact portion 236. When the adjustment member 220 is fixed, the outer surface contact portion 236 contacts the outer surface of the head (outer surface of the crown). In this embodiment, the portion excluding the boss portion 234 and the through projection portion 241 is the outer surface contact portion 236.

[0053] The outer portion 224 has a through projection 241. The through projection 241 protrudes from the outer surface contact portion 236 (bottom surface 232). When the adjustment member 220 is fixed, the through projection 241 protrudes from the inner surface of the head toward the inside of the head 200 while penetrating the main body wall portion 214. Except for the presence or absence of the through projection 241, the outer portion 224 is the same as the outer portion 124 of the first embodiment.

[0054] The inner portion 122 is the same as the inner portion 122 of the first embodiment (Figures 5(a) to (d)). The inner portion 122 has a base portion 142 and an outwardly extending portion 144. The base portion 142 has a cylindrical portion 146, a bottom portion 148, and a screw hole 150. The outwardly extending portion 144 extends outward from the outer edge (cylindrical portion 146) of the base portion 142. The outwardly extending portion 144 is provided at multiple locations (2 locations) in the circumferential direction of the base portion 142. The screw hole 150 forms an internal thread. The screw hole 150 is screwed into the threaded portion 128 of the rotating connecting portion 126. The inner portion 122 has an internal contact portion 152. When the adjustment member 220 is fixed, the internal contact portion 152 contacts the inner surface of the head (inner surface of the crown). In this embodiment, the cylindrical portion 146 and the outwardly extending portion 144 constitute the inner surface contact portion 152.

[0055] The cross-sectional view of the fixed state in the second embodiment (the cross-sectional view along line AA in Figure 8) is the same as that in Figure 3 of the first embodiment.

[0056] As shown in Figure 9, an opening 254 is formed in the main body wall 214 of the head body 202. The opening 254 penetrates the main body wall 214. The opening 254 has a circular portion 256, an outward-extending portion 258 extending outward from the circular portion 256, and a secondary opening 259. The shape formed by the circular portion 256 and the outward-extending portion 258 corresponds to the shape of the inner portion 122 in a plan view. The secondary opening 259 is connected to the opening 254 (circular portion 256). The secondary opening 259 is located at a different position from the outward-extending portion 258. The penetrating projection 241 penetrates the secondary opening 259.

[0057] In this embodiment, the sub-opening 259 is connected to the opening 254. The sub-opening 259 does not have to be connected to the opening 254. The sub-opening 259 may be separate from the opening 254.

[0058] Figure 12 is a diagram illustrating the method of attaching the adjustment member 220. Figure 12 is a plan view of the head 200 (head body 202) as seen from the inside.

[0059] The head body 202 has a head inner surface 202b. The head inner surface 202b includes the crown inner surface 206b. In the first embodiment described above, the head body 102 (body wall portion 114) has a body projection 164 that protrudes from the head inner surface 102b. In contrast, in the second embodiment, the head body 202 does not have a body projection. As described above, in the second embodiment, the outer portion 224 has a through projection 241. The through projection 241 penetrates the body wall portion 214 and protrudes from the head inner surface 202b toward the inside of the head 200. This through projection 241 is the anti-rotation portion 262. This projection 241 is also called the anti-rotation projection.

[0060] To install the adjustment member 220, first, an assembly 260 (Figure 11) is created. In this assembly 260, a gap is provided between the inner surface contact portion 152 of the inner portion 122 and the outer surface contact portion 236 of the outer portion 224 so that the main body wall portion 214 can be sandwiched between them.

[0061] Next, the inner part 122 of the assembly 260 is inserted into the opening 254 (step St1). During this insertion, the rotational position of the inner part 122 is adjusted so that it can pass through the opening 254. That is, the inner part 122 is adjusted to a position where it can pass through. In addition, the rotational position of the outer part 224 is adjusted so that the through projection 241 passes through the sub-opening 259. The topmost figure in Figure 12 is a view from the inside of the head 200 showing the state in which the inner part 122 has passed through the opening 254 and the through projection 241 has passed through the sub-opening 259. At this stage, the inner part 122 is located inside the head body 202. The through projection 241 also protrudes from the inner surface 202b of the head toward the inside of the head 200.

[0062] Next, the pivoting connecting portion 126 is rotated in the fastening direction (step St2). At this time, the inner portion 122 rotates together with the pivoting connecting portion 126. As the co-rotation progresses, the outwardly extending portion 144 of the inner portion 122 approaches the through projection 241 (co-rotation prevention portion 262).

[0063] Next, the outwardly extending portion 144 comes into contact with the through-projection portion 241 (step St3). This contact prevents the inner portion 122 from rotating together. With rotation prevented, the rotating connecting portion 126 is further rotated in the fastening direction. This rotation causes the rotating connecting portion 126 to rotate without the inner portion 122 rotating, and the screw fastening proceeds. As a result, fastening by the rotating connecting portion 126 is completed, and a fixed state is achieved.

[0064] In the second embodiment as well, the inner portion 122 is prevented from rotating together. In the second embodiment, there is no need to provide the main body projection 164, and it is sufficient to provide the sub-opening 259. Therefore, the molding of the head body 202 becomes easier. Also, by using a material with excellent moldability for the outer portion 224, the through projection 241 can be easily formed. Furthermore, the rotational position of the outer portion 224 can be precisely specified by the engagement between the sub-opening 259 and the through projection 241. Therefore, the mounting accuracy of the outer portion 224 is improved. Although the outer portion 224 and the rotating connection portion 126 are not screw-connected, the outer portion 224 can rotate together with the rotating connection portion 126 due to frictional force. The engagement between the sub-opening 259 and the through projection 241 can prevent the outer portion 224 from rotating together.

[0065] Figure 13 is a perspective view of the head 300 of the third embodiment. Figure 14 is a perspective view of the head body 302 of the head 300.

[0066] The head 300 has a face portion 304, a crown portion 306, a sole portion 308, and a hosel portion 310. The hosel portion 310 has a hosel hole 312. The head 300 has a hollow structure. The head 300 has an adjustment member 320.

[0067] The adjustment member 320 has an inner portion 322, an outer portion 324, and a pivotable connecting portion 126. The pivotable connecting portion 126 is the same as the pivotable connecting portion 126 of the first embodiment.

[0068] As shown in Figure 14, the head body 302 has an opening 354. The shape of the opening 354 corresponds to the shape of the inner portion 322 in a plan view (see Figure 16(b)). The opening 354 has a circular portion 356 and an outwardly extending portion 358 that extends outward from the circular portion 356.

[0069] Figure 15(a) is a plan view of the outer part 324, Figure 15(b) is a bottom view of the outer part 324, and Figure 15(c) is a perspective view of the outer part 324 as seen from the bottom side.

[0070] The outer portion 324 has an upper surface 330 and a bottom surface 332. In the fixed state of the adjustment member 320, the upper surface 330 is exposed. In the fixed state of the adjustment member 320, the bottom surface 332 faces the outer surface of the head (outer surface of the crown). The outer portion 324 has a boss portion 334. The boss portion 334 has a cylindrical portion 338 and a through hole 340 formed at the bottom of the cylindrical portion 338. The head 127 of the pivotable connecting portion 126 is housed in the cylindrical portion 338. The through hole 340 has an inner diameter that the head 127 cannot pass through. On the bottom surface 332 of the outer portion 324, the boss portion 334 protrudes (see Figure 15(c)). The threaded portion 128 of the pivotable connecting portion 126 is inserted through the through hole 340. The through hole 340 is not screwed into the threaded portion 128. The boss portion 334 holds the rotatable connecting portion 126 so that it can rotate freely.

[0071] The outer portion 324 has an outer surface contact portion 336. When the adjustment member 320 is fixed, the outer surface contact portion 336 contacts the outer surface of the head (outer surface of the crown). In this embodiment, the portion excluding the boss portion 334 is the outer surface contact portion 336.

[0072] The outer circumferential surface of the boss portion 334 has a small diameter portion 360 and a large diameter portion 362. The large diameter portion 362 constitutes a projection that protrudes radially outward. Two large diameter portions 362 (projections) are formed at two locations in the circumferential direction of the boss portion 334. The two large diameter portions 362 are arranged at equal intervals (180° intervals) in the circumferential direction. There may be only one large diameter portion 362 (projection).

[0073] Figure 16(a) is a perspective view of the inner part 322, Figure 16(b) is a plan view of the inner part 322, Figure 16(c) is a bottom view of the inner part 322, and Figure 16(d) is a side view of the inner part 322.

[0074] The inner portion 322 has a base portion 342 and an outwardly extending portion 344. The base portion 342 has a cylindrical portion 346, a bottom portion 348, and a screw hole 350. The outwardly extending portion 344 extends outward from the outer edge (cylindrical portion 346) of the base portion 342. The outwardly extending portion 344 is provided at multiple locations (2 locations) in the circumferential direction of the base portion 342. The screw hole 350 forms an internal thread. The screw hole 350 is screwed into the threaded portion 128.

[0075] The inner portion 322 has an inner surface contact portion 352. When the adjustment member 320 is fixed, the inner surface contact portion 352 contacts the inner surface of the head. In this embodiment, the cylindrical portion 346 (upper end surface) and the outwardly extending portion 344 are the inner surface contact portion 352.

[0076] The inner portion 322 has an inward projection 364. The inward projection 364 protrudes radially inward from the inner circumferential surface of the cylindrical portion 346. The projection height of the inward projection 364 corresponds to the projection height of the large diameter portion 362 in the boss portion 334 of the outer portion 324. Two inward projections 364 are provided. The multiple inward projections 364 are arranged at equal intervals in the circumferential direction. Except for the presence of the inward projections 364, the inner portion 322 is the same as the inner portion 122 of the first embodiment.

[0077] Figure 17 is a perspective view of the assembly 370, in which all the components of the adjustment member 320 have been assembled. The adjustment member 320 is attached to the head body 302 in its assembled state as the assembly 370. The difference between the adjustment member 320 and the adjustment member 120 lies in the shape of the boss portion on the outer side and the presence or absence of an inward protrusion on the inner side. Therefore, the assembly 370 is visually identical to the assembly 160 (Figure 6) of the first embodiment. The adjustment member 320 can be retrofitted to the head body 302. The adjustment member 320 can be attached to the head body 302 from the outside. The adjustment member 320 can also be removed from the outside of the head body 302.

[0078] Figure 18 is a diagram illustrating the method of attaching the adjustment member 320. Similar to Figures 7 and 12, Figure 18 is a view from the inside of the head 300 (head body 302).

[0079] In Figure 18, the portion hidden by the bottom 348 of the inner portion 322 is shown by a dashed line. The dashed lines represent the inward projection 364 and the boss portion 334 of the inner portion 322. However, since the movement of each component is difficult to understand from these dashed lines alone, separate hatching has been added to the inner portion 322 and the boss portion 334.

[0080] The head body 302 has an inner surface 302b. Unlike the first embodiment (Figure 7), the head body 302 does not have a body projection 164. Also, unlike the second embodiment (Figure 10(b)), the outer part 324 does not have a through projection 241.

[0081] In installing the adjustment member 320, first an assembly 370 (Figure 17) is created. In this assembly 370, a gap is provided between the inner surface contact portion 352 of the inner portion 322 and the outer surface contact portion 336 of the outer portion 324 so that the main body wall portion 114 can be sandwiched between them.

[0082] Next, the inner part 322 of the assembly 370 is inserted into the opening 354 (Figure 14) (Step St1). During this insertion, the phases of the inner part 322 and the opening 354 are aligned. That is, the rotational position of the inner part 322 is adjusted to the passing position. The top diagram of Figure 18 shows the state in which the inner part 322 has passed through the opening 354, as seen from inside the head 300. At this stage, the inner part 322 is located inside the head body 302.

[0083] Next, the pivoting coupling portion 126 is rotated in the fastening direction (step St2). At this time, the inner portion 322 rotates together with the pivoting coupling portion 126. As the co-rotation progresses, the inward projection 364 of the inner portion 322 approaches the large diameter portion 362 of the boss portion 334. Due to this co-rotation, the rotational position of the inner portion 322 shifts to a non-passing position.

[0084] Next, the inward projection 364 comes into contact with the large-diameter portion 362 (step St3). This contact prevents co-rotation. With co-rotation prevented, the rotating connecting portion 126 is further rotated in the fastening direction. This rotation causes the rotating connecting portion 126 to rotate without the inner portion 322 rotating, and screw fastening proceeds. As a result, fastening by the rotating connecting portion 126 is completed, and a fixed state is achieved.

[0085] When removing the adjustment member 320, the rotating connecting portion 126 is rotated in the opposite direction to when it was fastened. At this time, the inner portion 322 may rotate together, but eventually the inwardly protruding portion 364 will come into contact with the large-diameter portion 362, preventing it from rotating together. Thus, the fastening by the rotating connecting portion 126 can be loosened. After that, the rotational position of the inner portion 322 is adjusted to the passing position, and the opening 354 is passed through the inner portion 322, thereby separating the assembly 370 (adjustment member 320) from the head body 302. In this embodiment, a rotation restricting portion is formed between the inner portion 322 and the outer portion 324, which restricts their relative rotation at a predetermined rotational position. In this embodiment, this rotation restricting portion is a co-rotation prevention portion.

[0086] Figure 19(a) is a perspective view of the head body 402 according to the fourth embodiment, Figure 19(b) is a perspective view of the outer portion 424 of the adjustment member 420 according to the fourth embodiment, and Figure 19(c) is a perspective view of the head 400 according to the fourth embodiment. The head 400 has a head body 402 and an adjustment member 420. The adjustment member 420 has an outer portion 424, an inner portion, and a rotating connecting portion 126. The inner portion is not shown in Figures 19(a) to (c), but is the same as the inner portion 122 of the first embodiment (Figures 5(a) to (d)).

[0087] The outer portion 424 has through-projections 441 on its bottom surface 432 (outer surface contact portion 436). Two through-projections 441 are provided. In the second embodiment (Figure 10(b)), there was one through-projection 241, but in this embodiment, two through-projections 441 are provided. Except for this point, the outer portion 424 is the same as the outer portion 224 of the second embodiment.

[0088] An opening 454 is formed in the head body 402. The opening 454 has a circular portion 456, an outward-extending portion 458 extending outward from the circular portion 456, and a sub-opening 459. The shape formed by the circular portion 456 and the outward-extending portion 458 corresponds to the shape of the inner portion 122 in a plan view. The sub-opening 459 is connected to the circular portion 456. The sub-opening 459 is located at a different position from the outward-extending portion 458. Two sub-openings 459 are provided. Each of the through-projections 441 penetrates each of the sub-openings 459. Similar to the second embodiment, the through-projections 441 protrude from the inner surface of the head toward the inside of the head 400. The through-projections 441 function as anti-rotation projections (anti-rotation parts).

[0089] When the two through-projections 441 are inserted into the two sub-openings 459, there are two possible rotational positions for the outer portion 424. These are referred to as the first rotational position and the second rotational position. The phase difference between the first rotational position and the second rotational position is 180°. The case where the outer portion 424 is in the first rotational position is shown by a solid line in Figure 19(c). The case where the outer portion 424 is in the second rotational position is shown by a dashed line in Figure 19(c). Depending on the rotational position of the outer portion 424, for example, the aerodynamic characteristics of the head 400 change. Depending on the rotational position of the outer portion 424, for example, the center of gravity of the head 400 changes. In the head 400, the orientation (rotational position) of the outer portion 424 can be adjusted.

[0090] Figure 20(a) is a perspective view of the head body 502 according to the fifth embodiment, Figure 20(b) is a perspective view of the outer portion 224 of the adjustment member 220 according to the fifth embodiment, and Figure 20(c) is a perspective view of the head 500 according to the fifth embodiment. The head 500 has a head body 502 and an adjustment member 220. The adjustment member 220 has an outer portion 224, an inner portion, and a rotating connecting portion 126. The adjustment member 220 is the same as the adjustment member 220 of the second embodiment. The inner portion is not shown in Figures 20(a) to (c), but is the same as the inner portion 122 of the first embodiment (Figures 5(a) to (d)).

[0091] The outer portion 224 is the same as the outer portion 224 of the second embodiment. The outer portion 224 has a through projection 241 on its bottom surface 232 (outer surface contact portion 236). One through projection 241 is provided.

[0092] An opening 554 is formed in the head body 502. The opening 554 has a circular portion 556, an outward-extending portion 558 extending outward from the circular portion 556, and a sub-opening 559. The shape formed by the circular portion 556 and the outward-extending portion 558 corresponds to the shape of the inner portion 122 in a plan view. There are two sub-openings 559. The sub-openings 559 are connected to the circular portion 556. Each sub-opening 559 is located at a different position from the outward-extending portion 558. The through-projection 241 penetrates one of the sub-openings 559. Similar to the second embodiment, the through-projection 241 protrudes from the inner surface of the head toward the inside of the head 500. The through-projection 241 functions as a co-rotation prevention projection (co-rotation prevention portion).

[0093] The through projection 241 can be inserted into either of the two sub-openings 559. The rotational position of the outer portion 224 changes depending on which sub-opening 559 is selected. Therefore, the outer portion 224 can be fixed in two rotational positions. The first rotational position and the second rotational position have a phase difference of 45°. The case where the outer portion 224 is in the first rotational position is shown by a solid line in Figure 20(c). The case where the outer portion 224 is in the second rotational position is shown by a dashed line in Figure 20(c). The rotational position of the outer portion 224 changes, for example, the aerodynamic characteristics of the head 500. The rotational position of the outer portion 224 changes, for example, the center of gravity of the head 500. The orientation (rotational position) of the outer portion 224 can be adjusted in the head 500.

[0094] Figure 21(a) is a perspective view of the head body 602 according to the sixth embodiment, Figure 21(b) is a perspective view of the outer portion 624 of the adjustment member 620 according to the sixth embodiment, and Figures 21(c) and 21(d) are perspective views of the head 600 according to the sixth embodiment. The head 600 has a head body 602 and an adjustment member 620. The adjustment member 620 has an outer portion 624, an inner portion (not shown), and a rotating connecting portion 626. The adjustment member 620 is the same as the adjustment member 420 of the fourth embodiment except that its overall dimensions have been reduced. The inner portion is not shown in Figures 21(a) to (d), but it has the same shape as the inner portion 122 of the first embodiment, and its overall dimensions have been reduced. The rotating connecting portion 626 also corresponds to these dimensions.

[0095] The outer portion 624 is the same as the outer portion 424 of the fourth embodiment, except that its overall dimensions have been reduced. The outer portion 624 has a boss portion 634 and a through projection 641 on its bottom surface 632 (outer surface contact portion 636). Two through projections 641 are provided. The two through projections 641 are arranged along a straight line that intersects with and is perpendicular to the center line of the boss portion 634.

[0096] An opening 654 is formed in the head body 602. The opening 654 has a circular portion 656, an outward-extending portion 658 extending outward from the circular portion 656, and a sub-opening 659. The shape formed by the circular portion 656 and the outward-extending portion 658 corresponds to the shape of the inner portion in a plan view. There are four sub-openings 659. Two sub-openings 659 are arranged along a straight line, and two other sub-openings 659 are arranged along another straight line. The sub-openings 659 are connected to the circular portion 656. Each sub-opening 659 is located at a different position from the outward-extending portion 658. Two through-projections 641 pass through two of the four sub-openings 659. Similar to the second embodiment, the through-projections 641 project from the inner surface of the head toward the inside of the head 600. The through-projections 641 function as anti-rotation projections (anti-rotation parts).

[0097] When the two through-projections 641 are inserted into any two of the four sub-openings 659, there are four possible rotational positions for the outer portion 624. Therefore, the outer portion 624 can be fixed in four rotational positions, from the first to the fourth. The first rotational position and the second rotational position are 180° apart in phase. The case where the outer portion 624 is in the first rotational position is shown by a solid line in Figure 21(c). The case where the outer portion 624 is in the second rotational position is shown by a dashed-dot line in Figure 21(c). The third rotational position and the fourth rotational position are 180° apart in phase. The case where the outer portion 624 is in the third rotational position is shown by a solid line in Figure 21(d). The case where the outer portion 624 is in the fourth rotational position is shown by a dashed-dot line in Figure 21(d). The first rotational position and the third rotational position differ in phase by 60°. The rotational position of the outer part 624 changes, for example, the aerodynamic characteristics of the head 600. The rotational position of the outer part 624 also changes, for example, the center of gravity of the head 600. The orientation (rotational position) of the outer part 624 can be adjusted in the head 600.

[0098] Figure 22(a) is a perspective view of the head body 702 according to the seventh embodiment, Figure 22(b) is a bottom view of the outer portion 724 of the adjustment member 720 according to the seventh embodiment, and Figure 22(c) is a perspective view of the head 700 according to the seventh embodiment. The head 700 has a head body 702 and an adjustment member 720. The adjustment member 720 has an outer portion 724, an inner portion (not shown), and a pivotable connecting portion 126. The adjustment member 720 is the same as the adjustment member 320 of the third embodiment, except that the outer portion 724 has an outer engaging portion 741. The inner portion is not shown in Figures 22(a) to (c), but is the same as the inner portion 322 of the third embodiment (Figures 16(a) to (d)).

[0099] The outer portion 724 is the same as the outer portion 324 of the third embodiment (Figures 15(a) to (c)), except that it has an outer engaging portion 741. The outer portion 724 has a boss portion 734 and an outer engaging portion 741. The outer engaging portion 741 is a protrusion that protrudes from the bottom surface 772 of the outer portion 724. In this embodiment, as in the third embodiment (Figure 18), a co-rotation prevention portion is formed between the outer portion and the inner portion. The outer engaging portion 741 may also be a recess.

[0100] An opening 754 is formed in the head body 702. The opening 754 has a circular portion 756 and an outwardly extending portion 758 that extends outward from the circular portion 756. Furthermore, a body engagement portion 759 is provided in the head body 702. The body engagement portion 759 is a through hole. The body engagement portion 759 is provided away from the opening 754. An outer engagement portion 741 is inserted into the body engagement portion 759. The outer engagement portion 741, which is a convex portion, penetrates the body engagement portion 759. The outer engagement portion 741 is in a position where the inner portion cannot come into contact with it. The outer engagement portion 741 is not a co-rotation prevention portion. In this embodiment, since a co-rotation prevention portion is formed between the outer portion and the inner portion, the outer engagement portion 741 does not need to be a co-rotation prevention portion. The engagement between the body engagement portion 759 and the outer engagement portion 741 specifies the orientation (rotation position) of the outer portion 724. The engagement between the main engagement portion 759 and the outer engagement portion 741 prevents the outer portion 724 from rotating together when the pivoting connecting portion 126 is rotated. The main engagement portion 759 may be a recess that does not penetrate the main body wall, or it may be a protrusion. The main engagement portion 759 is shaped to engage with the outer engagement portion 741. If the outer engagement portion 741 is a recess, the main engagement portion 759 may be a protrusion.

[0101] Figure 23(a) is a perspective view of the head body 802 according to the eighth embodiment, Figure 23(b) is a bottom view of the outer portion 824 of the adjustment member 820 according to the eighth embodiment, and Figure 23(c) is a perspective view of the head 800 according to the eighth embodiment. The head 800 has a head body 802 and an adjustment member 820. The adjustment member 820 has an outer portion 824, an inner portion (not shown), and a pivotable connecting portion 126. The adjustment member 820 is the same as the adjustment member 320 of the third embodiment, except that the outer portion 824 has an outer engaging portion 841. The inner portion is not shown in Figures 23(a) to (c), but is the same as the inner portion 322 of the third embodiment (Figures 16(a) to (d)).

[0102] The outer portion 824 is the same as the outer portion 324 of the third embodiment (Figures 15(a) to (c)), except that it has an outer engaging portion 841. The outer portion 824 has a boss portion 834 and an outer engaging portion 841. Two outer engaging portions 841 are provided. The outer engaging portion 841 is a protrusion that protrudes from the bottom surface 872 of the outer portion 824. In this embodiment, as in the third embodiment (Figure 18), a co-rotation prevention portion is formed between the outer portion and the inner portion. Note that the outer engaging portion 841 may be a recess.

[0103] An opening 854 is formed in the head body 802. The opening 854 has a circular portion 856 and an outwardly extending portion 858 that extends outward from the circular portion 856. Furthermore, the head body 802 has a body engagement portion 859. Two body engagement portions 859 are provided corresponding to two outer engagement portions 841. The body engagement portions 859 are provided away from the opening 854. The body engagement portions 859 are recesses that do not penetrate the body wall. Each of the outer engagement portions 841 is inserted into each of the body engagement portions 859. Each outer engagement portion 841 is in a position where the inner portion cannot come into contact with it. Each outer engagement portion 841 is not a co-rotation prevention portion. In this embodiment, since a co-rotation prevention portion is formed between the outer portion and the inner portion, the outer engagement portion 841 does not need to be a co-rotation prevention portion. The engagement between the body engagement portion 859 and the outer engagement portion 841 determines the orientation (rotation position) of the outer portion 824. The two main engagement portions 859 and the outer engagement portion 841 further improve the accuracy of aligning the rotational position of the outer portion 824. The engagement between the main engagement portion 859 and the outer engagement portion 841 can prevent the outer portion 824 from rotating together when the pivoting coupling portion 126 is rotated. The main engagement portion 859 may be a through hole or a protrusion. The main engagement portion 859 is shaped to engage with the outer engagement portion 841. If the outer engagement portion 841 is a recess, the main engagement portion 859 may be a protrusion.

[0104] Figure 24(a) is a perspective view of the head 900 of the ninth embodiment as seen from the crown side, and Figure 24(b) is a perspective view of the head 900 as seen from the sole side. The head 900 has a face portion 904, a crown portion 906, a sole portion 908, and a hosel portion 910. The head 900 has an adjustment member 120 and an adjustment member 920. The adjustment member 120 is provided on the crown portion 906. The adjustment member 120 is positioned on the heel side of the face center. The adjustment member 920 is provided on the sole portion 908. The adjustment member 920 is positioned on the toe side of the face center. Multiple adjustment members may be provided as in this embodiment. The number of adjustment members is not limited. The position of the adjustment members is not limited. The position and number of adjustment members can be appropriately set according to the purpose of providing the adjustment members.

[0105] Figure 25(a) is a cross-sectional view of the head 1000 of the tenth embodiment near the adjustment member. Figure 25(a) is a cross-sectional view in a fixed state. The main body wall portion 1014 of the head body 1002 of the head 1000 has an opening 1054. The adjustment member 1020 is fixed to this opening 1054. The adjustment member 1020 has an inner portion 1022, an outer portion 1024, and a pivotable connecting portion 126. The main body wall portion 1014 is sandwiched between the inner portion 1022 and the outer portion 1024.

[0106] Figure 25(b) is a cross-sectional view of the vicinity of the adjustment member in head 1000a according to a modified example of the 10th embodiment. In the adjustment member 1030 of head 1000a, an outer part 1032 is used instead of an outer part 1024. The outer part 1032 has a different outer shape from the outer part 1024. Except for the difference in the outer part, head 1000a is the same as head 1000.

[0107] The difference between head 1000 and head 100 of the first embodiment is that the head body 1002 is provided with a flat portion 1040 whose radius of curvature on the outer surface of the head is larger than that of the peripheral portion 1042. Adjustment members 1020 and 1030 are fixed to the flat portion 1040. The head body 1002 has a peripheral portion 1042 around the flat portion 1040. The peripheral portion 1042 is adjacent to the flat portion 1040. In the peripheral portion 1042, the outer surface of the head body 1002 is a convex curved surface. The peripheral portion 1042 is provided on the crown portion.

[0108] In Figures 25(a) and 25(b), the symbol R1 indicates the radius of curvature of the outer surface of the head body 1002 in the flat portion 1040. In Figures 25(a) and 25(b), the symbol R2 indicates the radius of curvature of the outer surface of the head body 1002 in the peripheral portion 1042. The radius of curvature R1 is greater than the radius of curvature R2. The radii of curvature R1 and R2 are measured in a cross-section that includes the center line S of the pivoting coupling portion 126. In all cross-sections that include the center line S, the radius of curvature R1 is greater than the radius of curvature R2. As in this embodiment, the radius of curvature R1 may be infinite. That is, in the flat portion 1040, the outer surface of the head may be a plane. The peripheral portion 1042 surrounds the entire perimeter of the flat portion 1040.

[0109] By providing the flat portion 1040, the effective protrusion height of the adjustment member on the outer surface of the head can be reduced. In the embodiment shown in Figure 25(a), the radius of curvature of the outer surface of the outer portion 1024 is made to substantially match the radius of curvature R2 of the surrounding portion 1042. As a result, the adjustment member is in a state where it does not substantially protrude. Also, the outer edge 1026 of the outer portion 1024 coincides with the outer edge of the flat portion 1040. The outer surface of the outer portion 1024 is connected to the outer surface of the surrounding portion 1042. In the embodiment shown in Figure 25(b), the protrusion height of the adjustment member 1030 is also reduced due to the flat portion 1040.

[0110] In Figure 25(a), the double arrow W1 indicates the width of the peripheral portion 1042. From the viewpoint of suppressing the appearance of the adjustment member protruding, the width W1 is preferably 5 mm or more, more preferably 7 mm or more, and more preferably 10 mm or more. Considering the dimensions of the head, the width W1 may be 40 mm or less, more preferably 30 mm or less, and more preferably 20 mm or less. The width W1 is measured in a cross section including the center line S of the pivoting connection portion 126. The width W1 is measured in a direction perpendicular to the center line S. The minimum value of W1 is the minimum value of the width W1 measured in each cross section including the center line S. Note that when the outer portion 1024 is positioned near the contour of the crown portion, the width from the outer edge 1026 of the outer portion 1024 to the contour of the crown portion may be the above width W1. In this case, at the outer edge 1026 close to the contour of the crown portion, the width W1 may be less than 5 mm, more preferably 3 mm or less, more preferably 1 mm or less, and even 0 mm. This 0mm means that the outer edge 1026 coincides with the contour of the crown. For the outer edge 1026 that is 5mm or more away from the contour of the crown, the width W1 may be within the above preferred range (5mm to 40mm).

[0111] Figure 26 is a cross-sectional view of the head 1100 of the 11th embodiment near the adjustment member. Figure 26 is a cross-sectional view in a fixed state. The adjustment member 1120 of the head 1100 has an inner portion 1122, an outer portion 1124, and a pivotable connecting portion 1126. The outer portion 1124 has a boss portion 1134. The pivotable connecting portion 1126 has a head portion 1127 and a screw portion 1128. The head portion 1127 is housed in the boss portion 1134. The adjustment member 1120 is fixed to the main body wall portion 114 (head body 102). Except for the configuration described below, the adjustment member 1120 is the same as the adjustment member 120, and the head 1100 is the same as the head 100.

[0112] The head portion 1127 of the pivoting coupling portion 1126 has a recess 1136 on its outer circumferential surface. The recess 1136 is a circumferential groove. The boss portion 1134 has a recess 1138 on its inner circumferential surface. The recess 1138 is a circumferential groove. In the fixed state of the adjustment member 1120, the recesses 1136 and 1138 face each other. A ring member 1140 is positioned between the recesses 1136 and 1138. The ring member 1140 may be, for example, a C-shaped washer. The ring member 1140 is fitted into the recess 1136. By engaging with the recesses 1136 and 1138, the ring member 1140 prevents the pivoting coupling portion 1126 from falling off the outer portion 1124. Thus, a fall prevention part is provided between the rotatable connecting part 1126 and the outer part 1124, which allows the rotatable connecting part 1126 to rotate relative to the outer part 1124 while preventing the rotatable connecting part 1126 from falling off the outer part 1124.

[0113] Figure 27 is a cross-sectional view of the head 1200 of the twelfth embodiment near the adjustment member. Figure 27 is a cross-sectional view in a fixed state. The adjustment member 1220 of the head 1200 has an inner part 122, an outer part 124, and a rotating connecting part 126. The rotating connecting part 126 has a head 127 and a threaded part 128. A cap 1222 is attached to the tip of the threaded part 128. The adjustment member 1220 is fixed to the main body wall 114 (head body 102). Except for the presence of the cap 1222, the adjustment member 1220 is the same as the adjustment member 120 of the first embodiment, and the head 1200 is the same as the head 100.

[0114] The presence of the cap 1222 prevents the threaded portion 128 from screwing into the threaded hole 150 of the inner portion 122. The cap 1222 restricts the range of motion of the inner portion 122 relative to the threaded portion 128. The cap 1222 restricts the movement of the inner portion 122 toward the tip of the threaded portion 128. When installing the adjustment member 1220, if the inner portion 122 is excessively far from the main body wall portion 114, the inner portion 122 will have difficulty contacting the anti-rotation portion 162 (see Figure 7). In this case, contact with the anti-rotation portion 162 can be achieved by lifting the entire adjustment member 1220, but this may reduce the ease of installation of the adjustment member 1220. By restricting the movement of the inner portion 122 toward the tip of the threaded portion 128, the inner portion 122 can more easily come into smooth contact with the anti-rotation portion 162. Therefore, the ease of installation of the adjustment member 1220 is improved.

[0115] Figure 28 is a cross-sectional view of the head 1300 of the 13th embodiment near the adjustment member. Figure 28 is a cross-sectional view in a fixed state. The adjustment member 1320 of the head 1300 has an inner portion 122, an outer portion 1324, and a rotating connecting portion 126. The adjustment member 1320 is fixed to the main body wall portion 114 (head body 102). Except for the shape of the outer portion 1324, the adjustment member 1320 is the same as the adjustment member 120 of the first embodiment, and the head 1300 is the same as the head 100.

[0116] The outer part 1324 has a large height from the outer surface of the head. The outer part 1324 is a heavy component. The weight of the outer part 1324 is greater than the weight of the inner part 122. The specific gravity of the outer part 1324 is greater than the specific gravity of the inner part 122. The volume of the outer part 1324 is greater than the volume of the inner part 122. If the outer part 1324 is a heavy component, the large height of the outer part 1324 can allow for a larger adjustment range of the head's center of gravity.

[0117] In Figure 28, the double arrow H1 indicates the height of the outer part 1324. Height H1 is the height from the outer surface of the main body wall 114 (head body 102). Height H1 may differ at each point on the outer surface of the main body wall 114. Height H1 is measured along the normal to the outer surface of the main body wall 114. Height H1 is measured in a fixed state. From the viewpoint of increasing the adjustment amount of the head's center of gravity, the maximum value of height H1 can be 3 mm or more, further 4 mm or more, and further 5 mm or more. If height H1 is excessive, the weight distributed to the head body will decrease, and the design freedom of the head body will decrease. From this viewpoint, the maximum value of height H1 can be 10 mm or less, further 9 mm or less, and further 8 mm or less.

[0118] Figure 29 is a cross-sectional view of the head 1400 of the 14th embodiment near the adjustment member. Figure 29 is a cross-sectional view of the fixed state. The adjustment member 1420 of the head 1400 has an inner portion 1422, an outer portion 1424, and a rotating connecting portion 126. The adjustment member 1420 is fixed to the main body wall portion 114 (head body 102).

[0119] The outer part 1424 has a small height from the outer surface of the head. The outer part 1424 is a heavy component. The inner part 1422 is a heavy component. The weight of the inner part 1422 is greater than the weight of the outer part 1424. The volume of the inner part 1422 is greater than the volume of the outer part 1424. The small protrusion height of the outer part 1424 can reduce its influence on the head's center of gravity. Therefore, for example, if the adjustment member 1420 is placed on the crown, the rise in the head's center of gravity is suppressed.

[0120] From the perspective of minimizing the impact on the head's center of gravity, the maximum value of height H1 may be 6mm or less, even 5mm or less, and even 4mm or less. From the perspective of increasing the weight of the outer part 1424, the maximum value of height H1 may be 3mm or more, even 2mm or more, and even 1mm or more.

[0121] In Figure 29, the double arrow H2 indicates the height of the inner part 1422. Height H2 is the height from the inner surface of the main body wall 114 (head body 102). Height H2 may differ at each point on the inner surface of the main body wall 114 (head body 102). Height H2 is measured along the normal to the inner surface of the main body wall 114. Height H2 is measured in a fixed state. From the viewpoint of increasing the weight of the inner part 1422, the maximum value of height H2 may be 3 mm or more, further 4 mm or more, and further 5 mm or more. If the weight of the inner part 1422 is excessive, the weight distributed to the head body will decrease, reducing the design freedom of the head body. From this viewpoint, the maximum value of height H2 may be 15 mm or less, further 12 mm or less, and further 10 mm or less.

[0122] Figure 30 is a cross-sectional view of the head 1500 of the 15th embodiment near the adjustment member. In the head 1500, an elastic portion 1502 is provided between the head outer surface 102a and the outer portion 124. Except for the presence of the elastic portion 1502, the head 1500 is the same as the head 100 of the first embodiment. The elastic portion 1502 is fixed to the bottom surface 132 of the outer portion 124.

[0123] The elastic portion 1502 fills the gap between the head outer surface 102a and the outer portion 124. The elastic portion 1502 contributes to the stable fixing of the adjustment member 120. As in the fourth to sixth embodiments described above, when the rotational position of the outer portion 124 is selectable, a gap is likely to occur between the head outer surface 102a and the outer portion 124. The elastic portion 1502 can absorb the difference in shape between the head outer surface 102a and the bottom surface 132 of the outer portion 124 and fill this gap.

[0124] From the viewpoint of effectively absorbing the shape difference between the head outer surface 102a and the outer part 124, the Young's modulus of the elastic body constituting the elastic part 1502 is preferably 0.3 GPa or less, more preferably 0.2 GPa or less, and even more preferably 0.1 GPa or less. From the viewpoint of stably fixing the adjustment member 120, this Young's modulus is preferably 0.01 GPa or more, more preferably 0.02 GPa or more, and even more preferably 0.03 GPa or more. Examples of this elastic body include elastomers such as rubber and sponges. Examples of sponges include synthetic sponges and rubber sponges made by foaming resin.

[0125] Figure 31(a) is a perspective view of the head body 1602 according to the 16th embodiment, Figure 31(b) is a bottom view of the outer portion 1624 of the adjustment member 1620 according to the 16th embodiment, and Figure 31(c) is a perspective view of the head 1600 according to the 16th embodiment. The head 1600 has a head body 1602 and an adjustment member 1620. The adjustment member 1620 has an outer portion 1624, an inner portion (not shown), and a rotating connecting portion 126. The adjustment member 1620 is the same as the adjustment member 720 of the 7th embodiment. The inner portion is not shown in Figures 31(a) to (c), but is the same as the inner portion 322 of the 3rd embodiment (Figures 16(a) to (d)).

[0126] The outer portion 1624 is the same as the outer portion 724 in the seventh embodiment. The outer portion 1624 has a boss portion 1634 and an outer engaging portion 1641. The outer engaging portion 1641 is a protrusion that protrudes from the bottom surface 1672 of the outer portion 1624. In this embodiment, as in the third embodiment (Figure 18), a co-rotation prevention portion is formed between the outer portion 1624 and the inner portion. The outer engaging portion 1641 may also be a recess.

[0127] An opening 1654 is formed in the head body 1602. The opening 1654 has a circular portion 1656 and an outwardly extending portion 1658 that extends outward from the circular portion 1656. Furthermore, the head body 1602 is provided with a body engagement portion 1659. The body engagement portion 1659 is a through hole. Multiple (two) body engagement portions 1659 are provided. The body engagement portions 1659 are provided away from the opening 1654. An outer engagement portion 1641 is inserted into one of the two body engagement portions 1659. The engagement between the body engagement portion 1659 and the outer engagement portion 1641 specifies the orientation (rotation position) of the outer portion 1624. The engagement between one of the body engagement portions 1659 and the outer engagement portion 1641 prevents the outer portion 1624 from rotating together when the rotating coupling portion 126 is rotated. The main body engagement portion 1659 may be a recess that does not penetrate the main body wall, or it may be a protrusion. The main body engagement portion 1659 is shaped to engage with the outer engagement portion 1641. If the outer engagement portion 1641 is a recess, the main body engagement portion 1659 may be a protrusion. Except for the provision of the second main body engagement portion 1659, the head body 1602 is the same as the head body 702 of the seventh embodiment.

[0128] In this 16th embodiment, the rotational position of the outer portion 1624 changes depending on which body engagement portion 1659 is selected. In this 16th embodiment, there are multiple rotational positions of the outer portion 1624 when the outer engagement portion 1641 engages with the body engagement portion 1659.

[0129] When one outer engaging portion 1641 is engaged with two main body engaging portions 1659, there are two possible rotational positions of the outer portion 1624. These are referred to as the first rotational position and the second rotational position. The phase difference between the first rotational position and the second rotational position is 180°. The case where the outer portion 1624 is in the first rotational position is shown by a solid line in Figure 31(c). The case where the outer portion 1624 is in the second rotational position is shown by a dashed line in Figure 31(c). Depending on the rotational position of the outer portion 1624, for example, the aerodynamic characteristics of the head 1600 change. Depending on the rotational position of the outer portion 1624, for example, the center of gravity of the head 1600 changes. In the head 1600, the orientation (rotational position) of the outer portion 1624 can be adjusted.

[0130] Each embodiment described above has the following effects. Note that reference numerals will be omitted as appropriate in the following description.

[0131] Despite the fact that each adjustment component is structured to sandwich the main body wall from both the inside and outside of the head body, the adjustment component can be retrofitted to the head body. In other words, the adjustment component can be attached and detached from the outside of the head. Therefore, the adjustment component can be attached, detached, and replaced on the product's head.

[0132] The anti-rotation mechanism prevents the inner part, located inside the head body, from rotating together with the rotating coupling. Therefore, the adjustment member can be securely fixed from the outside of the head.

[0133] The anti-rotation part can be provided on the main body wall of the head body, as shown in the main body protrusion 164 of the first embodiment (Figures 2 and 7). In this case, it is not necessary to provide the anti-rotation part on the adjustment member.

[0134] As explained in Figure 7, when the inner part 122 is inserted from the outside of the head, the inner part 122 is in a state where it can pass through the opening 154. That is, at this time, the rotational position of the inner part 122 is in a passing position where it can pass through the opening 154. In this passing position, the inner part 122 cannot clamp the main body wall 114. By utilizing the co-rotation with the rotating connecting part 126, the rotational position of the inner part 122 is shifted from the passing position to a non-passing position where it cannot pass through the opening 154. In the non-passing position, the inner part 122 can clamp the main body wall 114 between itself and the outer part 124. The position of the co-rotation prevention part is set so that when the inner part 122 comes into contact with it, the rotational position of the inner part 122 becomes the non-passing position. Therefore, the inner part 122 can be reliably shifted to the non-passing position.

[0135] The anti-rotation portion can also be provided on the outer side, as in the through-projection portion 241 of the second embodiment (Figure 10(b)). The through-projection portion 241 penetrates the sub-opening 259 of the head body (Figure 9) and protrudes from the inner surface of the head toward the inside of the head. The engagement of the through-projection portion 241 and the sub-opening 259 determines the orientation (rotation position) of the adjustment member 220. Therefore, the adjustment member 220 can be accurately attached. In addition, misalignment of the adjustment member 220 is prevented, and the fixing strength of the adjustment member 220 is increased.

[0136] Both the through-projection on the outer part and the body projection on the head body are positioned so that the inner part, which rotates together with the pivoting coupling, can come into contact with them. As a result, these projections function as anti-rotation parts.

[0137] The anti-co-rotation part can also be provided within the adjustment member 220, as in the third embodiment. As explained in Figure 18, in the third embodiment, an engagement part is formed between the inner part 322 and the outer part 324 that restricts relative rotation between them at a specific rotation position. This engagement part is a rotation restricting part that restricts relative rotation between the inner part 322 and the outer part 324 at a specific rotation position. In the third embodiment, this rotation restricting part is the anti-co-rotation part.

[0138] In the fourth embodiment (Figure 19(c)), the fifth embodiment (Figure 20(c)), and the sixth embodiment (Figures 21(c), (d)), the adjustment member can be fixed in multiple orientations (rotational positions). In these embodiments, multiple sub-openings are provided. There are multiple rotational positions of the outer part when the through-projection is inserted into the sub-opening. Therefore, the orientation of the adjustment member can be adjusted. Furthermore, the through-projection also functions as a co-rotation prevention part. In the sixteenth embodiment (Figure 31(c)), the adjustment member can also be fixed in multiple orientations (rotational positions). In these embodiments, multiple main body engagement parts are provided. There are multiple rotational positions of the outer part when the outer engagement part engages with the main body engagement part. Therefore, the orientation of the adjustment member can be adjusted.

[0139] The anti-rotation part does not have to be a protruding part. For example, the shape of the inner surface of the head may be configured so that it makes contact with the rotating inner part.

[0140] The role of the adjustment member is not limited. The adjustment member may, for example, be an aerodynamic member that adjusts the aerodynamic characteristics of the head. When used as an aerodynamic member, it is preferable that the average specific gravity of the entire adjustment member is smaller than the average specific gravity of the entire head body. The adjustment member may also be a weight. When used as a weight, it is preferable that the average specific gravity of the entire adjustment member is larger than the average specific gravity of the entire head body. The adjustment member may also adjust the shape (outer shape) of the head.

[0141] The specific gravity of each part constituting the adjustment member is not limited. For example, the specific gravity of the inner part can be made greater than that of the outer part, and the specific gravity of the rotating joint can be made greater than that of the inner part. In this order, the movement of the center of gravity to the outside of the head can be suppressed. Therefore, for example, when the adjustment member is provided on the crown, the rise of the head's center of gravity is suppressed. This effect is particularly preferable when the adjustment member is used as an aerodynamic member. On the other hand, the specific gravity of the rotating joint can be made greater than that of the inner part, and the specific gravity of the outer part can be made greater than that of the rotating joint. In this order, the head's center of gravity is more likely to move to the outside of the head. This effect is particularly preferable when it is used as a weight.

[0142] In each of the embodiments described above, the outer part and the rotating connecting part are separate components. The outer part and the rotating connecting part may be integrated. In this case, the outer part will rotate together with the rotating connecting part. For example, if the outer part is circular, the outer part may be equivalent regardless of its rotational position. In such a case, for example, the outer part and the rotating connecting part may be integrated.

[0143] The following additional information is disclosed regarding the embodiments described above. [Note 1] A head body having a main body wall portion that forms the inner surface and outer surface of the head, At least one adjustment member is detachably fixed to the outer surface of the head in a manner that it sandwiches the main body wall, It is equipped with, The head body has at least one opening that penetrates the body wall, The adjustment member, An inner portion having an inner surface contact portion that contacts the inner surface of the head, An outer portion having an outer surface contact portion that contacts the outer surface of the head, It has a rotating connecting part that connects the inner part and the outer part, The rotational position of the inner portion includes a passing position in which it can pass through the opening and a non-passing position in which it cannot pass through the opening. In the non-pass position, the inner surface contact portion is in contact with the inner surface of the head. A golf club head having a co-rotation prevention portion that prevents the head body or the adjustment member from rotating together with the rotating connecting portion at the non-passing position. [Note 2] The golf club head according to Appendix 1, wherein the anti-rotation portion is at least one anti-rotation projection that protrudes from the inner surface of the head toward the inside of the head. [Note 3] The main body wall portion has at least one main body projection that protrudes from the inner surface of the head toward the inside of the head, The golf club head as described in Appendix 2, wherein the main body protrusion is the anti-rotation protrusion. [Note 4] The outer portion has at least one through-projection that penetrates the main body wall and protrudes from the inner surface of the head toward the inside of the head, The head body has at least one sub-opening through which the through-projection passes, The golf club head as described in Appendix 2, wherein the through-projection is the anti-rotation projection. [Note 5] The aforementioned sub-openings are multiple, The golf club head according to Appendix 4, wherein the rotational position of the outer portion when the through-projection is inserted into the sub-opening is multiple. [Note 6] A rotation restricting portion is formed between the outer portion and the inner portion, which restricts their relative rotation at a specific rotational position. The golf club head as described in Appendix 1, wherein the rotation restricting portion is the co-rotation prevention portion. [Note 7] The aforementioned outer portion further includes an outer engaging portion which is a convex or concave portion that engages with the main body wall portion. The aforementioned main body wall portion further has a main body engaging portion that engages with the aforementioned outer engaging portion, A golf club head according to any one of the appendices 1 to 6, wherein the outer engaging portion and the main body engaging portion do not constitute the anti-rotation portion. [Note 8] The main body engagement portion is a through hole that penetrates the main body wall, The golf club head as described in Appendix 7, wherein the outer engaging portion is the convex portion and penetrates the main body engaging portion. [Note 9] The golf club head as described in Appendix 7, wherein the main body engagement portion is a main body recess that engages with the protrusion on the outer part and does not penetrate the main body wall, or a main body protrusion that engages with the recess on the outer part. [Note 10] The main body engagement portion is multiple, The golf club head according to any one of the appendices 7 to 9, wherein there are multiple rotational positions of the outer portion when the outer portion engages with the main body engaging portion. [Note 11] The golf club head according to any one of the appendices 1 to 10, wherein the outer portion and the rotating connecting portion are separate components. [Note 12] The golf club head as described in Appendix 11, wherein a fall prevention portion is formed between the outer portion and the rotatable connecting portion, which allows the rotatable connecting portion to rotate relative to the outer portion while preventing the rotatable connecting portion from falling off the outer portion. [Explanation of Symbols]

[0144] 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1000a, 1100, 1200, 1300, 1400, 1500, 1600... Golf club heads 102, 202, 302, 402, 502, 602, 702, 802, 1002, 1602... Head body 114, 214, 1014... Main wall section 120, 220, 320, 420, 620, 720, 820, 920, 1020, 1030, 1120, 1220, 1320, 1420, 1620... Adjustment parts 122, 322, 1022, 1122, 1422, 1622...Inside 124, 224, 324, 424, 624, 724, 824, 1024, 1032, 1124, 1324, 1424, 1624...Outer part 136, 236, 336, 436, 636...Outer surface contact part 126, 1126... Rotating coupling section 152, 352...Inner surface contact part 154, 254, 354, 454, 554, 654, 754, 854, 1054, 1654... Openings 162... Anti-rotation section 164... Main body protrusion (anti-rotation protrusion) 241, 441, 641, ... Through-projection (anti-rotation projection) 262... Anti-rotation section

Claims

1. A head body having a main body wall portion that forms the inner surface and outer surface of the head, At least one adjustment member is detachably fixed to the outer surface of the head in a manner that it sandwiches the main body wall, It is equipped with, The head body has at least one opening that penetrates the body wall, The adjustment member, An inner portion having an inner surface contact portion that contacts the inner surface of the head, An outer portion having an outer surface contact portion that contacts the outer surface of the head, It has a rotating connecting part that connects the inner part and the outer part, The inner portion is a separate component from the rotating connecting portion. The rotational position of the inner portion includes a passing position in which it can pass through the opening and a non-passing position in which it cannot pass through the opening. In the non-pass position, the inner surface contact portion is in contact with the inner surface of the head. A golf club head having a co-rotation prevention portion that prevents the head body or the adjustment member from rotating together with the rotating connecting portion at the non-passing position.

2. The golf club head according to claim 1, wherein the anti-rotation portion is at least one anti-rotation projection that protrudes from the inner surface of the head toward the inside of the head.

3. The main body wall portion has at least one main body projection that protrudes from the inner surface of the head toward the inside of the head, The golf club head according to claim 2, wherein the main body protrusion is the co-rotation prevention protrusion.

4. The outer portion has at least one through-projection that penetrates the main body wall and protrudes from the inner surface of the head toward the inside of the head, The head body has at least one sub-opening through which the through-projection passes, The golf club head according to claim 2, wherein the through-projection is the co-rotation prevention projection.

5. The aforementioned sub-openings are multiple, The golf club head according to claim 4, wherein there are multiple rotational positions of the outer portion when the through-projection is inserted into the sub-opening.

6. A rotation restricting portion is formed between the outer portion and the inner portion, which restricts their relative rotation at a specific rotational position. The golf club head according to claim 1, wherein the rotation restricting portion is the co-rotation prevention portion.

7. The aforementioned outer portion further includes an outer engaging portion which is a convex or concave portion that engages with the main body wall portion. The aforementioned main body wall portion further has a main body engaging portion that engages with the aforementioned outer engaging portion, The golf club head according to any one of claims 2 to 6, wherein the outer engaging portion and the main body engaging portion do not constitute the co-rotation prevention portion.

8. The main body engagement portion is a through hole that penetrates the main body wall, The golf club head according to claim 7, wherein the outer engaging portion is the protruding portion and penetrates the main body engaging portion.

9. The golf club head according to claim 7, wherein the main body engaging portion is a main body recess that engages with the protrusion on the outer portion and does not penetrate the main body wall, or a main body protrusion that engages with the recess on the outer portion.

10. The main body engagement portion is multiple, The golf club head according to claim 7, wherein there are multiple rotational positions of the outer portion when the outer portion engages with the main body engaging portion.

11. The golf club head according to any one of claims 1 to 6, wherein the outer portion and the rotating connecting portion are separate members.

12. The golf club head according to claim 11, wherein a fall prevention portion is formed between the outer portion and the rotatable connecting portion, which allows the rotatable connecting portion to rotate relative to the outer portion while preventing the rotatable connecting portion from falling off the outer portion.

13. The golf club head according to any one of claims 1 to 6, wherein the rotating connecting portion is a screw and the inner portion is screwed into the rotating connecting portion.

14. The golf club head according to any one of claims 1 to 6, wherein the inner portion is pulled toward the outer portion, so that the main body wall is sandwiched between the inner portion and the outer portion.

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