JP5583717B2 - Golf club head and golf club - Google Patents

Description

  The present invention relates to a golf club head and a golf club provided with the same.

  In golf clubs, the ball flight distance is reduced when the sweet spot is removed and the ball is hit with a sweet spot. That is, when the sweet spot is removed and the ball is hit, the golf club head rotates around the center of gravity because the hit point deviates from the sweet spot. This rotation reduces the flight distance of the ball.

  In order to suppress the decrease in the flight distance, it has been proposed to suppress the rotation of the golf club head. In order to suppress the rotation of the golf club head, it has been proposed to increase the moment of inertia of the golf club head.

  For example, Japanese Patent Laying-Open No. 2005-278800 (Patent Document 1) discloses increasing the moment of inertia around the center of gravity in the crown / sole direction while matching the sweet spot of the golf club head with the center of the face. Yes. Japanese Patent Laid-Open No. 2006-296500 (Patent Document 2) discloses that a fiber reinforced resin material member is used for a golf club head to increase the moment of inertia by increasing the volume of a hollow portion while suppressing an increase in mass. Is disclosed. Japanese Patent Laid-Open No. 2007-7276 (Patent Document 3) realizes weight reduction and increase of moment of inertia by using a laminate of a carbon fiber reinforcing material and a titanium alloy fibrous material for a golf club head. Is disclosed.

JP-A-2005-278800 JP 2006-296500 A JP 2007-7276 A

  However, in recent years, the upper limit of the head volume is determined by a rule, and it is difficult to increase the moment of inertia by increasing the head volume. In particular, each golf club head described in each of the above publications has a shape that lies on an extension line of a conventional golf club head, and thus it is difficult to greatly improve the moment of inertia of the golf club head. .

  The present invention has been made in view of the above problems, and an object thereof is to provide a golf club head capable of greatly improving the moment of inertia and a golf club provided with the same.

The golf club head of the present invention has a crown portion having a crown side opening, a sole portion facing the crown portion and having a sole side opening, and a wall defining an internal space that communicates the crown side opening and the sole side opening. Part, face part, toe part and heel part . The projected area of the internal space viewed from the crown side is the position viewed from the crown side when the golf club head is installed on a horizontal plane so as to form the set loft angle and lie angle (hereinafter referred to as the installed state). The projected area of the golf club head is 40% or more and 90% or less. The sole side opening has an arch shape that curves toward the crown side. A hollow region is formed between each of the face portion, the toe portion, the heel portion, and the rear end of the golf club head and the wall portion, and the weight portion is formed in the hollow region between the rear end of the golf club head and the wall portion. Is formed.

  According to the golf club head of the present invention, the golf club head can be significantly reduced in weight by the internal space that connects the crown side opening and the sole side opening. By distributing the excess mass generated by the weight reduction to a portion closer to the outer side of the head body, it is possible to concentrate the mass on a portion away from the center of gravity of the golf club head. Thereby, the moment of inertia of the golf club head can be greatly improved. Moreover, surplus mass can be arrange | positioned in arbitrary positions, and the freedom degree of design can be raised. As described above, a golf club head having desired performance can be obtained.

  By greatly improving the moment of inertia of the golf club head, the golf club head can be prevented from rotating around the center of gravity when the sweet spot is removed and hit. Thereby, when the sweet spot is removed and the ball is hit, the degree of decrease in the flight distance of the ball can be reduced.

  Further, since the crown side opening and the sole side opening are supported by the wall portion that defines the internal space that communicates the crown side opening and the sole side opening, the rigidity of the golf club head can be maintained. Therefore, the moment of inertia can be greatly improved while maintaining the rigidity of the golf club head.

  A large surplus mass can be generated by setting the projected area of the internal space viewed from the crown side to 40% or more of the projected area of the golf club head viewed from the crown side. Further, the strength can be secured by setting the projected area of the internal space viewed from the crown side to 90% or less of the projected area of the golf club head viewed from the crown side.

  In the above golf club head, the internal space is preferably partitioned into a plurality of spaces by a partition member. Thereby, since the partition member is supported by the internal space, the rigidity of the golf club head can be further improved.

  The above golf club head preferably further includes a lid, and the lid is attached so as to cover the crown side opening. By covering the crown side opening with the lid, the crown portion can be reinforced, and at the same time, the appearance can be eliminated.

  In the above golf club head, preferably, the crown portion includes a receiving portion provided at an outer peripheral end portion of the crown side opening and a joint portion provided so as to bridge the receiving portion. Since the receiving portion and the joint portion can be bonded to the lid, the bonding area of the lid can be increased. For this reason, the adhesive strength of the lid can be increased.

  The golf club of the present invention includes a shaft, a grip attached to one end of the shaft, and the above-described golf club head attached to the other end opposite to the grip of the shaft. Thereby, a golf club having a large moment of inertia can be obtained.

  As described above, according to the golf club head and the golf club of the present invention, it is possible to provide a golf club head capable of greatly improving the moment of inertia and a golf club including the same.

1 is a schematic top view of a golf club head according to an embodiment of the present invention. It is the schematic side view seen from the heel side of the golf club head in one embodiment of the present invention. 1 is a schematic perspective view of a golf club head according to an embodiment of the present invention. It is a schematic sectional drawing which follows the IV-IV line of FIG. It is a schematic sectional drawing in alignment with the VV line of FIG. It is a schematic top view which shows the golf club head in one embodiment of this invention, and the projection area of internal space. It is a schematic top view which shows the projection area of the golf club head in one embodiment of this invention. 1 is a schematic perspective view of an outer member of a golf club head in an embodiment of the present invention. It is a schematic sectional drawing in alignment with IX-IX of FIG. 1 is a schematic perspective view of an inner member of a golf club head according to an embodiment of the present invention. It is a schematic sectional drawing in alignment with XI-XI of FIG. It is a schematic perspective view of the modification 1 of the golf club head in one embodiment of the present invention. It is a schematic perspective view of the modification 2 of the golf club head in one embodiment of the present invention. It is a schematic perspective view of the modification 3 of the golf club head in one embodiment of the present invention. It is a schematic perspective view of the modification 4 of the golf club head in one embodiment of the present invention. 1 is a schematic rear view of a golf club according to an embodiment of the present invention. 1 is a schematic perspective view of a golf club head reflecting the concept of the present invention. 1 is a schematic top view of a golf club head reflecting the concept of the present invention. 1 is a schematic perspective view of an example of a golf club head reflecting the concept of the present invention. It is a schematic perspective view of the other example of the golf club head in which the concept of this invention was reflected.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the configuration of a golf club head according to an embodiment of the present invention will be described.

  1 to 3, a golf club head 10 is a wood type golf club head. The golf club head 10 includes a crown portion 1, a sole portion 2, a wall portion 3, a hosel portion 4, a face portion 5, a leading edge portion 6, a toe portion 7, a heel portion 8, and a top edge portion. 9 mainly.

  The crown part 1 is a part constituting the upper part of the golf club head 10. The crown portion 1 is disposed so as to cover the upper surface of the sole portion 2. The crown portion 1 has a crown side opening 1a. The crown side opening 1a is formed, for example, in a substantially circular shape when viewed from the crown portion 1 side.

  The sole portion 2 is a portion constituting the bottom portion of the golf club head 10. The sole part 2 has a sole side opening 2a. The sole side opening 2a is formed in a substantially circular shape when viewed from the sole portion 2 side, for example. The shape of the sole side opening 2a may have an arch shape that curves toward the crown portion 1 side. Thereby, since the contact area of the sole part 2 and the ground can be reduced at the time of impact, the friction caused by the contact between the sole part 2 and the ground can be reduced. For this reason, it is possible to suppress a reduction in head speed caused by contact between the sole portion 2 and the ground.

  The wall portion 3 is configured to define an internal space IS that allows the crown side opening 1a and the sole side opening 2a to communicate with each other. The internal space IS is a space surrounded by the wall 3. The components of the golf club head 10 are not arranged in the internal space IS. The center of gravity of the golf club head 10 is located in the internal space IS. The wall 3 is formed so as to connect the outer peripheral end of the crown side opening 1a and the outer peripheral end of the sole side opening 2a. By connecting the entire circumference of the crown side opening 1a and the sole side opening 2a, the stress concentration in the wall 3 can be suppressed.

  The hosel part 4 is a part connected to the shaft (FIG. 16). The face portion 5 has a hitting surface. A plurality of score line (groove) portions (not shown) may be formed on the hitting surface. The leading edge portion 6 is a portion where the sole portion 2 and the face portion 5 are in contact with each other. The toe portion 7 is a portion that connects the top edge portion 9 on the side away from the hosel portion 4 and the sole portion 2. The heel portion 8 is a portion from the lower end of the hosel portion 4 to the sole portion 2. The top edge portion 9 is a portion constituting the upper edge of the golf club head 10 from the hosel portion 4 to the toe portion 7.

  Referring to FIGS. 4 and 5, wall 3 is formed to be continuous from crown side opening 1 a to sole side opening 2 a. The internal space IS has substantially the same diameter from the crown portion 1 side to the sole portion 2 side. That is, the diameter of the crown side opening 1a and the diameter of the sole side opening 2a have substantially the same dimensions.

  In addition, the diameter of the crown side opening 1a and the diameter of the sole side opening 2a may not have substantially the same dimensions. That is, the diameter of the crown side opening 1a may be larger than the diameter of the sole side opening 2a. In this case, the internal space IS is formed in a tapered shape whose diameter decreases from the crown side opening 1a toward the sole side opening 2a. The diameter of the sole side opening 2a may be larger than the diameter of the crown side opening 1a. In this case, the internal space IS is formed in a tapered shape whose diameter increases from the crown side opening 1a toward the sole side opening 2a.

  The golf club head 10 has a hollow region between the wall portion 3 and the face portion 5. Similarly, a hollow region is formed between the wall 3 and the toe 7 and between the wall 3 and the heel 8. On the other hand, a hollow region is also formed between the wall 3 and the rear end of the golf club head 10, and a weight portion 11 is formed in the region. The weight distribution of the golf club head 10 can be adjusted by the weight portion 11. The moment of inertia can be increased by positioning the weight portion 11 at a position away from the center of gravity of the golf club head 10 by the weight portion 11.

  With reference to FIG. 6 and FIG. 7, the projected area PA1 of the internal space IS viewed from the crown portion 1 side and the projected area PA2 of the golf club head 10 viewed from the crown portion 1 side will be described. The projected area PA1 of the internal space IS viewed from the crown portion 1 side is obtained by projecting the opening 1a on the crown portion 1 side onto a horizontal plane in a state viewed from the crown portion 1 side to the sole portion 2 side in the installed state. It is the smaller one of the area of the crown side opening 1a and the area of the sole side opening 2a obtained by projecting the opening 2a on the sole portion 2 side on a horizontal plane. The projected area PA2 of the golf club head 10 viewed from the crown 1 side is an area in which the crown 1 is drawn on a horizontal plane when viewed from the crown 1 side to the sole 2 side.

  FIG. 6 is a view of the golf club head 10 viewed from the crown portion 1 side in the installed state, where the areas of the crown side opening 1a and the sole side opening 2a are substantially equal, and the crown side opening 1a and the sole side opening 2a Are in a positional relationship where they overlap each other on a horizontal plane. In FIG. 6, since the area of the crown side opening 1a and the sole side opening 2a is substantially the same, the projected area PA1 of the internal space IS is either the area of the crown side opening 1a or the area of the sole portion 2 side opening 2a. It corresponds to crab. As shown in FIG. 6, it is preferable that the projected area PA1 of the internal space IS viewed from the crown 1 side is 40% or more and 90% or less of the projected area PA2 of the golf club head 10 viewed from the crown 1 side. For convenience of explanation, FIG. 7 shows a projected area PA2 as viewed from the crown 1 side of the golf club head 10.

The projected area PA2 of the golf club head 10 viewed from the crown 1 side can be set to 1275.6 mm ² , for example. As shown in FIG. 6, the projected area PA1 of the internal space IS viewed from the crown 1 side can be set to 8459.7 mm ² , for example. In this case, the projected area PA1 of the internal space IS is approximately 67% of the projected area PA2 of the golf club head 10.

Further, in the golf club head 10 provided with the internal space IS having a mass substantially equal to the mass of the golf club head 10 not provided with the internal space IS, the projected area PA1 of the internal space IS viewed from the crown portion 1 side. Is, for example, 5222.7 mm ² . In this case, the projected area PA1 of the internal space IS is about 41% of the projected area PA2 of the golf club head 10. Since the ratio of the projected area PA1 of the internal space IS to the projected area PA2 of the golf club head 10 is also affected by the shape of the golf club head 10 main body, the ratio is approximately 40% or more, and the effect of weight reduction is achieved.

  Further, if the projected area PA1 of the internal space IS viewed from the crown 1 side exceeds 90% of the projected area PA2 of the golf club head 10 viewed from the crown 1 side, it is difficult to ensure the durability of the head body. Furthermore, it is difficult to manufacture the golf club head 10.

  When the area of the crown side opening 1a is different from the area of the sole side opening 2a, the ratio of the projected area PA1 of the smaller opening to the projected area PA2 of the golf club head 10 is approximately 40%. The ratio of the projected area PA1 of the opening having the larger area to the projected area PA2 of the golf club head 10 should be approximately 90% or less, thereby obtaining the effect of reducing the weight and ensuring the strength. Can do.

Next, a method for manufacturing the golf club head according to the present embodiment will be described.
The golf club head 10 of the present embodiment can be manufactured by various methods. For example, the upper member (crown portion 1 side member) and the lower member (sole portion 2 side member) of the golf club head 10 are respectively casted. Both members are welded at the split surface between the upper member and the lower member. All the upper members may be made by casting, and the face portion 5 may be plate-welded. The weight portion 11 may be welded after the lower member is manufactured, or may be manufactured by casting integrally with the lower member.

  Further, the front portion of the golf club head 10 may be manufactured with a cup face by forging. In this case, the hosel part 4 is welded to the front part.

  Moreover, the crown part 1, the hosel part 4, the face part 5, the sole part 2, and the side part may be produced by forging. In this case, an opening may be formed in the crown portion 1 and the sole portion 2 by a trim mold. The wall 3 may be a cylindrical casting or a pipe obtained by a general manufacturing method.

  8 to 11, the golf club head 10 may be manufactured by welding an outer member 10a and an inner member 10b manufactured by casting. With reference to FIGS. 8 and 9, the outer member 10 a is configured by a portion other than the wall portion 3. With reference to FIG. 10 and FIG. 11, the inner member 10 b is configured by the wall portion 3. The outer member 10a and the inner member 10b are welded to each other at a portion constituting the crown opening 1a and a portion constituting the sole side opening 2a. The face portion 5 may be welded later with a plate or cup-shaped member. According to this manufacturing method, the golf club head 10 can be easily manufactured.

Subsequently, a modified example of the golf club head of the present embodiment will be described.
With reference to FIG. 12, Modification 1 of the golf club head 10 of the present embodiment includes a partition member 12. The internal space IS is partitioned by a partition member 12 into a plurality of space portions SP. Since the partition member 12 is provided so as to extend from one side to the other side of the internal space IS, the rigidity of the golf club head 10 is improved.

  In the first modification, the partition member 12 is provided so as to extend from the face part 5 side to the rear side, and is provided so as to extend from the toe part 7 side to the heel part 8 side. Since the partition member 12 extends from the face portion 5 side to the rear side, the rigidity at the time of hitting can be increased. The partition member 12 is provided so as to intersect at the center of the internal space IS. As a result, the internal space IS is divided into four space portions SP by the partition member 12.

  With reference to FIG. 13, the second modification of the golf club head 10 of the present embodiment is formed so that the thickness of the partition member 12 is larger than that of the first modification. The inside of the partition member 12 is also formed in a hollow shape. Moreover, the junction part of the crown part 1 and the wall part 3 is formed in the taper shape toward the inner side of internal space IS.

  With reference to FIG. 14, Modification 3 of the golf club head 10 of the present embodiment includes a lid 13. The lid 13 is attached so as to cover the crown side opening 1a. The outer peripheral part of the lid body 13 may be bonded to the outer peripheral end part of the crown side opening 1a with an adhesive. The lid 13 is preferably lightweight.

  Referring to FIG. 15, the crown portion 1 includes a receiving portion 14 and a joint portion 15. The receiving part 14 is provided in the outer peripheral end part of the crown side opening 1a. The receiving portion 14 may have a certain width along the outer peripheral end portion of the crown side opening 1a. The joining portion 15 is provided so as to bridge the receiving portion 14.

  The joint portion 15 is provided so as to extend from the face portion 5 side to the rear side, and is provided so as to extend from the toe portion 7 side to the heel portion 8 side. Since the joint portion 15 extends from the face portion 5 side to the rear side, the rigidity at the time of hitting can be increased. The partition member 12 is provided so as to intersect at the center of the internal space IS in plan view. The lid 13 is bonded to the receiving portion 14 and the joint portion 15 with an adhesive. By providing the lid 13 in this way, it is possible to obtain an appearance similar to that of a conventional golf club head.

Next, the configuration of the golf club of the present embodiment will be described.
Referring to FIG. 16, golf club 20 is configured by combining golf club head 10 with shaft 21 and grip 22. The golf club 20 includes a shaft 21, a grip 22 attached to one end of the shaft 21, and a golf club head 10 attached to the other end opposite to the grip 22 of the shaft 21. Note that well-known shafts 21 and grips 22 can be employed. A socket 23 is attached to the shaft 21 so as to be adjacent to the hosel part 4 of the golf club head 10.

Next, the effect of this Embodiment is demonstrated.
According to the golf club head 10 of the present embodiment, the golf club head 10 can be significantly reduced in weight by the internal space IS that connects the crown side opening 1a and the sole side opening 2a. By distributing the surplus mass generated by the weight reduction to a portion closer to the outer side of the head body, the mass can be concentrated on a portion away from the center of gravity of the golf club head 10. Thereby, the moment of inertia of the golf club head 10 can be greatly improved. Moreover, surplus mass can be arrange | positioned in arbitrary positions, and the freedom degree of design can be raised. As described above, a golf club head having desired performance can be obtained.

  By greatly improving the moment of inertia of the golf club head 10, the golf club head 10 can be prevented from rotating around the center of gravity when the sweet spot is removed and hit. Thereby, when the sweet spot is removed and the ball is hit, the degree of decrease in the flight distance of the ball can be reduced.

  Further, since the crown side opening 1a and the sole side opening 2a are supported by the wall portion 3 that defines the internal space IS that communicates the crown side opening 1a and the sole side opening 2a, the rigidity of the golf club head 10 is maintained. can do. Therefore, the moment of inertia can be greatly improved while maintaining the rigidity of the golf club head 10.

  A large surplus mass can be generated by setting the projected area PA1 of the internal space IS viewed from the crown portion 1 side to 40% or more of the projected area PA2 of the golf club head 10 viewed from the crown portion 1 side. Further, the strength can be ensured by setting the projected area PA1 of the internal space IS viewed from the crown portion 1 side to 90% or less of the projected area PA2 of the golf club head 10 viewed from the crown portion 1 side.

  In the golf club head 10 of the present embodiment, the internal space IS is preferably partitioned by the partition member 12 into a plurality of space portions SP. Thereby, since the partition member 12 is supported by the internal space IS, the rigidity of the golf club head 10 can be further improved.

  In the golf club head 10 of the present embodiment, it is preferable that the golf club head 10 further includes a lid body 13 and the lid body 13 is attached so as to cover the crown side opening 1a. By covering the crown-side opening 1a with the lid 13, the crown portion 1 can be reinforced, and at the same time, the appearance can be eliminated. The appearance is not impaired.

  In the golf club head 10 of the present embodiment, the crown portion 1 includes a receiving portion 14 provided at the outer peripheral end of the crown side opening 1a and a joint portion 15 provided so as to bridge the receiving portion 14. Preferably it is. Since the receiving portion 14 and the joint portion 15 can be bonded to the lid body 13, the bonding area of the lid body 13 can be increased. For this reason, the adhesive strength of the lid can be increased. In addition, the lid 13 can be easily adhered.

  The golf club 20 of the present embodiment includes the golf club head 10 described above. Thereby, the golf club 20 having a large moment of inertia can be obtained.

  The configuration of the golf club head of the present embodiment is not limited to the above configuration. The golf club head may be configured to reflect the concept of the present invention. Next, the concept of the present invention will be described based on a golf club head in which the concept of the present invention is reflected.

  Referring to FIGS. 17 and 18, the golf club head 10 reflecting the concept of the present invention has a front part FP and a ring part RP attached to the rear of the front part FP. The upper part of the front part FP and the ring part RP constitutes a crown equivalent part. The portion corresponding to the crown corresponds to the crown portion 1. The crown side opening 1 a is formed at the upper end portion of the crown portion 1. That is, the crown side opening 1a is located at the upper end portion of the ring portion RP.

  A lower part of the front part FP, a part of the back part BP connected to the ring part RP from the lower part of the front part FP, and a lower part of the ring part RP constitute a sole equivalent part. A portion corresponding to the sole corresponds to the sole portion 2. The sole side opening 2 a is formed at the lower end portion of the sole portion 2. That is, the sole side opening 2a is located at the lower end of the ring portion RP.

  The portion of the back portion BP sandwiched between the inner peripheral portion of the ring portion RP and the ring portion RP constitutes a wall equivalent portion. A wall equivalent portion corresponds to the wall portion 3. A space defined by the wall portion 3 corresponds to the internal space IS. Since the ring portion RP has a cylindrical shape, the area of the internal space IS increases at the crown side opening 1a and the sole side opening 2a, and the inner diameter side of the ring portion RP (the crown side opening 1a and the sole side opening 2a It becomes smaller at the middle position. The projected area PA1 of the internal space IS viewed from the crown part 1 side corresponds to the area on the innermost diameter side of the ring part RP.

  The hosel part 4 is provided in the front part FP. The face part 5 is provided in front of the front part FP. A leading edge portion 6, a toe portion 7, a heel portion 8 and a top edge portion 9 are provided on the front portion FP.

  The golf club head 10 reflecting the concept of the present invention can be manufactured by various methods. For example, the front part FP may be cast. For example, the face portion 5 may be plate-welded. The ring part RP that has been bent may be welded to the back part BP. The ring portion RP may be cast in a curved state in advance. The weight part 11 may be provided in the ring part RP.

  Moreover, with reference to FIG. 19, the partition member 12 may be provided. In this example, the partition member 12 is provided so as to extend from the back portion BP to the rear end of the ring portion RP. As a result, two space portions SP are provided.

  Referring to FIG. 20, partition member 12 may be provided so as to intersect at the center of the space defined by ring portion RP and back portion BP. In this other example, the partition member 12 provides four space portions SP.

  A lid may be provided in the same manner as described above. In this case, the lid is preferably provided so as to cover the crown side opening 1a.

  Thus, if the concept of the present invention is reflected, the same effects as described above can be obtained.

Examples of the present invention will be described below.
With reference to Tables 1 to 3, Invention Examples 1 to 3 are examples of the present invention. Inventive Examples 1 to 3 have the same configuration as that of the above embodiment, and the area of the crown side opening 1a and the area of the sole part side opening 2a are substantially the same. Comparative Examples 1 to 3 are comparative examples for the present invention. Comparative Examples 1 to 3 do not have a crown side opening and a sole side opening. Therefore, no internal space is formed.

  As shown in Tables 1 to 3, the inertia moment TH in the toe heel direction and the inertia moment in the crown sole direction (vertical direction) UD were calculated for each case where the total mass of the golf club head was 180 g, 190 g, and 200 g. .

Referring to Table 1, when the total mass of the golf club head is 180 g, respectively inertia UD of inertia TH and crown sole direction Touhiru direction of Comparative Example 1 became ^{4280g · cm 2, 2680g · cm} 2 It was. On the other hand, the moment of inertia TH and inertia UD crown sole direction Touhiru direction of Invention Example 1 became ^{5050g · cm 2, 3310g · cm} 2 , respectively.

  Thus, the moment of inertia TH in the toe heel direction of Example 1 of the present invention was larger than that of Comparative Example 1. Further, the moment of inertia UD in the crown sole direction of Example 1 of the present invention was larger than that of Comparative Example 1.

Moment of inertia TH of Touhiru direction of Invention Example 1 becomes 4500 g · cm ² or more, the moment of inertia UD crown sole direction of the present invention Example 1 became 3000 g · cm ² or more.

Referring to Table 2, when the total mass of the golf club head is 190 g, respectively inertia UD of inertia TH and crown sole direction Touhiru direction of Comparative Example 2 became ^{4780g · cm 2, 2720g · cm} 2 It was. On the other hand, the moment of inertia UD of inertia TH and crown sole direction Touhiru direction of Invention Example 2 became ^{5500g · cm 2, 3740g · cm} 2 , respectively.

  Thus, the moment of inertia TH in the toe heel direction of Example 2 of the present invention was larger than that of Comparative Example 2. Further, the moment of inertia UD in the crown sole direction of Example 2 of the present invention was larger than that of Comparative Example 2.

Table 3 with reference to when the whole mass of the golf club head is 200 g, respectively inertia UD of inertia TH and crown sole direction Touhiru direction of Comparative Example 3 became ^{5160g · cm 2, 2810g · cm} 2 It was. On the other hand, the moment of inertia UD of inertia TH and crown sole direction Touhiru direction of Invention Example 3 became ^{5920g · cm 2, 4070g · cm} 2 , respectively.

  As a result, the moment of inertia TH in the toe heel direction of Example 3 of the present invention was larger than that of Comparative Example 3. Further, the moment of inertia UD in the crown sole direction of Example 3 of the present invention was larger than that of Comparative Example 3.

  Next, the mass of the golf club head according to the ratio (projection ratio) of the projected area PA1 of the internal space seen from the crown side to the projected area PA2 of the golf club head seen from the crown side was examined.

  As shown in Table 4, the head mass of the golf club head and the ratio (projection ratio) of the projected area PA1 of the internal space to the projected area PA2 were measured.

  Referring to Table 4, Invention Examples 4 and 5 are examples of the present invention. Invention Examples 4 and 5 have the same configuration as that of the above embodiment. Comparative Examples 4 to 6 are comparative examples for the present invention. Comparative Example 4 does not have a crown side opening, a sole, or a side opening. Therefore, no internal space is formed. Comparative Examples 5 and 6 have an internal space, but are different from Invention Examples 4 and 5 in that the projection ratio is smaller than that of Invention Examples 4 and 5.

  The head mass of Comparative Example 4 in which no internal space is formed is 180 g. In Comparative Examples 5 and 6 in which the internal space is formed, the head masses are 187 g and 181.8 g, respectively. Compared to Comparative Example 4, the head masses of Comparative Examples 5 and 6 are heavier. This is because the mass of the wall portions of Comparative Examples 5 and 6 is heavier than the mass of the crown portion and the sole portion of Comparative Example 4.

Since the internal space is not formed, in Comparative Example 4, the projected area PA1 of the internal space viewed from the crown side is 0 (zero). The projection area PA2 of Comparative Example 4 is 1275.6 mm ² . In Comparative Examples 5 and 6, the projection areas PA1 are 3769.8 mm ² and 4947.9 mm ² , respectively. In Comparative Examples 5 and 6, the projection area PA2 is 12715.6 mm ² . In Comparative Examples 5 and 6, the ratio (projection ratio) of the projection area PA1 to the projection area PA2 is 30% and 39%, respectively.

The head mass of Invention Example 4 is 180 g, the same as the head mass of Comparative Example 4. In Example 4 of the present invention, the projection area PA1 is 5222.7 mm ² . In the fourth example of the present invention, the projection area PA2 is 12715.6 mm ² . In Example 4 of the present invention, the projection ratio is 41%. Further, the head mass of Invention Example 5 is 179 g, which is lighter than the head mass of Comparative Example 4. In Example 5 of the present invention, the projection area PA1 is 5387.7 mm ² . In Example 5 of the present invention, the projection ratio is 42%.

  From the above, it was found that Example 4 of the present invention can have the same head mass as that of Comparative Example 4. Moreover, it turned out that it can be reduced in weight by this invention example 5 compared with the comparative example 4. Thereby, when the projection ratio exceeded 41%, it turned out that it can reduce in weight compared with the comparative example 4. Since the projection ratio is also affected by the shape of the golf club head main body, it is considered that the projection ratio can be reduced by approximately 40% or more.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be applied particularly advantageously to golf club heads and golf clubs.

  DESCRIPTION OF SYMBOLS 1 Crown part, 1a Crown side opening, 2 Sole part, 2a Sole side opening, 3 Wall part, 4 Hosel part, 5 Face part, 6 Leading edge part, 7 Toe part, 8 Heel part, 9 Top edge part, 10 Golf Club head, 11 weight part, 20 golf club, 21 shaft, 22 grip, 23 socket, IS internal space, projected area of PA1 internal space, projected area of PA2 golf club head.

Claims (5)

A crown portion having a crown side opening;
A sole portion facing the crown portion and having a sole-side opening;
A wall portion defining an internal space communicating the crown side opening and the sole side opening ;
With a face part, toe part and heel part ,
Projected area of the inner space viewed from the crown portion side, Ri 90% der than 40 percent of the projected area of the golf club head as viewed from the crown portion,
The sole side opening has an arch shape that curves toward the crown portion side,
A hollow region is formed between each of the face portion, the toe portion, the heel portion, and the rear end of the golf club head and the wall portion, and the rear end of the golf club head and the wall portion. the weight portions in the hollow area that is formed, the golf club head between.   The golf club head according to claim 1, wherein the internal space is partitioned into a plurality of space portions by a partition member. Further comprising a lid,
The golf club head according to claim 1, wherein the lid is attached so as to cover the crown side opening. The crown part is a receiving part provided at an outer peripheral end of the crown side opening;
The golf club head according to claim 3, further comprising a joint portion provided so as to bridge the receiving portion. A shaft,
A grip attached to one end of the shaft;
A golf club comprising: the golf club head according to claim 1, which is attached to the other end of the shaft opposite to the grip.

Images