US20230364477A1 - Golf club head - Google Patents
Golf club head Download PDFInfo
- Publication number
- US20230364477A1 US20230364477A1 US18/140,810 US202318140810A US2023364477A1 US 20230364477 A1 US20230364477 A1 US 20230364477A1 US 202318140810 A US202318140810 A US 202318140810A US 2023364477 A1 US2023364477 A1 US 2023364477A1
- Authority
- US
- United States
- Prior art keywords
- slit
- golf club
- main body
- head
- club head
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005484 gravity Effects 0.000 claims abstract description 44
- 239000000463 material Substances 0.000 claims abstract description 29
- 229920002430 Fibre-reinforced plastic Polymers 0.000 claims description 6
- 239000011151 fibre-reinforced plastic Substances 0.000 claims description 6
- 238000005452 bending Methods 0.000 description 8
- 230000002093 peripheral effect Effects 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 229910001069 Ti alloy Inorganic materials 0.000 description 4
- 239000007769 metal material Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 239000004918 carbon fiber reinforced polymer Substances 0.000 description 3
- 239000002023 wood Substances 0.000 description 3
- 229920000049 Carbon (fiber) Polymers 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 239000004917 carbon fiber Substances 0.000 description 2
- 238000005094 computer simulation Methods 0.000 description 2
- 235000009508 confectionery Nutrition 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 238000003780 insertion Methods 0.000 description 2
- 230000037431 insertion Effects 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 239000013585 weight reducing agent Substances 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910000952 Be alloy Inorganic materials 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910001240 Maraging steel Inorganic materials 0.000 description 1
- 229910000861 Mg alloy Inorganic materials 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000037396 body weight Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 239000013013 elastic material Substances 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000012783 reinforcing fiber Substances 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- LKJMGLFKGKSOCH-UHFFFAOYSA-N titanium Chemical compound [Ti].[Ti].[Ti] LKJMGLFKGKSOCH-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B53/00—Golf clubs
- A63B53/04—Heads
- A63B53/0466—Heads wood-type
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B53/00—Golf clubs
- A63B53/04—Heads
- A63B53/0408—Heads characterised by specific dimensions, e.g. thickness
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B53/00—Golf clubs
- A63B53/04—Heads
- A63B53/0433—Heads with special sole configurations
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B53/00—Golf clubs
- A63B53/04—Heads
- A63B53/0437—Heads with special crown configurations
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B60/00—Details or accessories of golf clubs, bats, rackets or the like
- A63B60/52—Details or accessories of golf clubs, bats, rackets or the like with slits
-
- A—HUMAN NECESSITIES
- A63—SPORTS; GAMES; AMUSEMENTS
- A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
- A63B2209/00—Characteristics of used materials
- A63B2209/02—Characteristics of used materials with reinforcing fibres, e.g. carbon, polyamide fibres
Definitions
- the face portion is lightened by using low specific gravity material for the face member.
- a weight margin is obtained. Distributing this weight margin away from the head center of gravity can provide a golf club head with a high moment of inertia.
- low specific gravity materials such as fiber reinforced plastic generally have low durability. Therefore, the face members made of low specific gravity materials need to be thick-walled.
- a thick-walled face member has high bending rigidity, which may reduce the repulsion performance of the club head when striking a ball.
- One object of the present disclosure is to provide a golf club head capable of reducing the weight of the face portion without deteriorating repulsion performance.
- a golf club head having a hollow portion therein, the head includes a main body including a crown portion and a sole portion, and a face member forming at least a part of a striking face for striking a ball.
- the main body is made of a first material having a first specific gravity.
- the face member is formed of a second material having a second specific gravity smaller than the first specific gravity.
- the main body is provided with at least one slit that penetrates the main body, and the at least one slit extends in a head-front-back direction.
- FIG. 1 is a perspective view of a golf club head according to an embodiment
- FIG. 2 is a front view of the golf club head according to an embodiment
- FIG. 3 is a plan view of the golf club head according to an embodiment
- FIG. 4 is a bottom view of the golf club head according to an embodiment
- FIG. 5 is a cross-sectional view taken along the lines V-V of FIG. 3 ;
- FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 3 ;
- FIG. 7 is a plan view of a slit
- FIG. 8 is a plan view of the slit according to another example.
- FIG. 9 is a plan view of the slit according to yet another example.
- FIG. 10 is a cross-sectional view taken along the lines X-X of FIG. 9 ;
- FIG. 11 is a bottom view of the golf club head according to another embodiment.
- FIG. 12 A is a front view of a golf club head
- FIG. 12 B is a cross-sectional view taken along the line s 1 of FIG. 12 A .
- FIGS. 1 to 4 respectively show a perspective view, a front view, a plan view, and a bottom view of a golf club head (hereinafter, simply referred to as “head”) 1 according to the present embodiment.
- an x-y-z coordinate system is associated with the head 1 .
- the x-axis is defined as the axis orthogonal to the reference vertical plane VP and parallel to the horizontal plane HP.
- the y-axis is parallel to both the reference vertical plane VP and the horizontal plane HP.
- the z-axis is defined as the axis orthogonal to both the x-axis and y-axis.
- the direction along the x-axis is defined as the head-front-back direction, the direction along the y-axis as the toe-heel direction, and the direction along the z-axis as the head-up-down direction.
- the side of the face portion 2 is the front side and the opposite side is the back side with respect to the head-front-back direction.
- the head 1 includes a hollow portion (i) therein.
- this hollow portion (i) may be used as a space as it is, or a gel agent for weight adjustment may be placed in a part of it.
- the head 1 is configured as a wood type.
- the head 1 of the wood type includes, for example, at least a driver, a fairway wood, a hybrid, and the like.
- the head 1 in this embodiment is configured as a driver.
- the head 1 includes a face portion 2 , a crown portion 3 , a sole portion 4 , a toe 5 and a heel 6 which are arranged so as to surround the hollow portion (i).
- the face portion 2 is the portion that strikes a ball and is formed on the front side of the head 1 .
- the face portion 2 includes a striking face 2 a that is in direct contact with the ball.
- the striking face 2 a may be provided with face lines.
- the face lines are grooves extending in the toe-heel direction.
- the face portion 2 includes a periphery E defining the boundary of the striking face 2 a .
- the periphery E of the face portion 2 is the ridge line if it is visible to the naked eye as a clear ridge line. On the other hand, if such a ridge line is not clearly formed, the periphery E of the face portion 2 is obtained as follows. First, as illustrated in FIG. 12 A , cross sections s 1 , s 2 , s 3 . . . , including the normal N passing the center of gravity G of the head and the sweet spot SS are specified. Next, as illustrated in FIG. 12 B , in each of the cross sections s 1 , s 2 , s 3 . . .
- the positions E where the radius of curvature r of the contour line Lf of the striking face 2 a becomes 200 mm for the first time from the sweet spot SS side toward outwardly of the face portion are specified, and a series of these positions E in the cross sections is defined as the periphery E of the face portion 2 .
- the boundary portion with the crown portion 3 is defined as the upper edge 2 b of the face portion 2
- the boundary portion with the sole portion 4 is defined as the lower edge 2 c of the face portion 2 .
- the crown portion 3 extends from the upper edge 2 b of the face portion 2 backwardly of the head so as to form an upper surface of the head.
- the hosel portion 7 is provided on the heel side of the crown portion 3 .
- the hosel portion 7 has the shaft insertion hole 7 a for fixing a shaft (not illustrated).
- the crown portion 3 is the portion excluding the face portion 2 and the hosel portion 7 in a plan view of the head shown in FIG. 3 .
- the sole portion 4 extends from the lower edge 2 c of the face portion 2 backwardly of the head so as to form a bottom surface of the head.
- the sole portion 4 is the portion excluding the hosel portion 7 in a bottom view of the head.
- FIG. 5 is a cross-sectional view taken along the lines V-V of FIG. 3 .
- the head 1 includes a main body 100 and a face member 200 .
- the main body 100 includes the crown portion 3 and the sole portion 4 .
- the main body 100 further includes the hosel portion 7 and a face peripheral portion 101 .
- the face peripheral portion 101 is the peripheral portion of the opening O formed in the face portion 2 .
- the face peripheral portion 101 forms the peripheral portion of the opening O formed in the face portion 2 .
- the main body 100 for example, includes the crown portion 3 , the sole portion 4 , the hosel portion 7 , and the face peripheral portion 101 integrally formed.
- the main body 100 may be formed by joining multiple members.
- the main body 100 is made of a first material having a first specific gravity.
- the first material is not particularly limited, one or more metallic materials may be suitable, for example. Examples of such metallic materials include titanium, titanium alloys, stainless steel, maraging steel, and the like.
- the first material is a metal material having a specific gravity equal to or more than 4.0, preferably equal to or more than 4.4, and titanium alloy (specific gravity of about 4.5) is particularly suitable.
- the first specific gravity may be specified by an average specific gravity obtained by weighting the specific gravity of each material by their volume.
- the face member 200 for example, has a plate-like shape. As shown in FIG. 1 , in the present embodiment, the face member 200 has a contour shape 200 e that is located inside of the periphery E of the striking face 2 a . The face member 200 is attached to an opening O formed in the main body 100 . Thus, the face member 200 constitutes at least a portion (in this embodiment, a major portion) of the striking face 2 a .
- the face member 200 is not limited to the plate-like shape of this embodiment, and may be, for example, a cup-like shape having a short length turnback portion extending behind of the head.
- the face peripheral portion 101 of the main body 100 is formed with a receiving portion 102 that supports the periphery of the back surface of the face member 200 .
- the face member 200 is more firmly attached to the face peripheral portion 101 .
- the fixing between the main body 100 and the face member 200 is not particularly limited, but may be performed using, for example, an adhesive or the like.
- the face member 200 is formed of a second material having a second specific gravity smaller than the first specific gravity.
- the second material is not particularly limited as long as it has a second specific gravity smaller than the first specific gravity.
- metal materials such as magnesium, magnesium alloys, aluminum, aluminum alloys, beryllium alloys, and the like may be employed.
- plastic materials such as fiber reinforced plastic can be adopted.
- a carbon fiber-reinforced plastic material (with a specific gravity of about 1.4) is used.
- the reinforcing fibers may be fibers other than carbon fibers.
- the thickness T of the face member 200 is, for example, equal to or less than 9.0 mm, preferably equal to or less than 8.5 mm, and more preferably equal to or less than 8.0 mm.
- FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 3
- FIG. 7 is an enlarged view of one of the slits 10 .
- each slit 10 has a Length L in the head-front-back direction, and a width W in the toe-heel direction.
- the length L of each slit 10 is larger than the width W of the slit 10 .
- each slit 10 is elongated in the head-front-back direction.
- the face portion 2 includes the face member 200 having the second specific gravity smaller than the first specific gravity of the main body 100 .
- the face portion 2 can be reduced in weight.
- the reduced weight of the face portion 2 provides a new weight margin.
- the weight margin means a discretionary and arbitrarily usable amount of weight not exceeding the weight limit set for the head 1 , usually used to adjust the center of gravity of the head 1 to a preferred location. By placing the weight margin farther from the center of gravity of the head, for example, it is possible to increase the moment of inertia around the axis passing through the center of gravity of the head.
- Such a golf club head can provide flexibility and stabilizes the direction of hit balls.
- the crown portion 3 is subjected to tensile deformation in the toe-heel direction in addition to bending deformation in the head-front-back direction.
- the sole portion 4 also shows almost the same deformation as the crown portion 3 . Therefore, if the tensile stiffness in the toe-heel direction of the main body 100 is reduced, the repulsion performance of the head 1 can be improved.
- the head 1 according to the present embodiment is composed of the face member 200 with high rigidity and the main body 100 with slits 10 extending in the head-front-back direction.
- the head 1 according to the present embodiment can reduce the weight of the face portion 2 without decreasing the repulsion performance.
- each slit 10 includes a frontmost end 10 a and a backmost end 10 b in the head-front-back direction. These frontmost end 10 a and backmost end 10 b are respectively located on the frontmost side of the slit 10 and on the backmost side of the head.
- the length L of the slits 10 is, for example, equal to or more than 10 mm, preferably equal to or more than 12 mm, more preferably equal to or more than 15 mm.
- the length L of the slits 10 is, for example, equal to or less than 40 mm, preferably equal to or less than 30 mm, more preferably equal to or less than 25 mm.
- the width W of the slits 10 is, for example, equal to or more than 0.5 mm, preferably equal to or more than 1 mm, more preferably equal to or more than 2 mm.
- a larger width W of the slits 10 may decrease the durability of the main body 100 .
- the width W of slits 10 is, for example, equal to or less than 10 mm, preferably equal to or less than 8 mm, more preferably equal to or less than 6 mm.
- the width W of the slits 10 can be constant or variable. Note that the width W of the slits 10 may be constant except at both ends, or it may vary as described below.
- each slit 10 defines a reference straight line 10 c passing through the frontmost end 10 a and the backmost end 10 b .
- the reference straight line 10 c of each slit 10 has an angle equal to or less than 15 degrees with respect to the head-front-back direction (i.e., the x-axis).
- Such a slit 10 can effectively promote the deflection of the main body 100 in the toe-heel direction when hitting a ball on the toe or heel side of the face portion.
- the angle of the reference straight line 10 c of each slit 10 is preferably equal to or less than 10 degrees, more preferably equal to or less than 5 degrees.
- the inclination direction of the reference straight line 10 c is not particularly limited.
- Each slit 10 of the present embodiment extends linearly parallel to the head-front-back direction, but one or more slits 10 may be formed in an arc, zigzag, wave, or other non-linear shape.
- each of contours on a frontmost end 10 a side and a backmost end 10 b side of the slit 10 preferably has an arc shape.
- each slit 10 does not have sharp corners near the frontmost end 10 a and/or the backmost end 10 b , which can relieve the stress concentration thereto.
- the frontmost end 10 a and the backmost end 10 b are both arc-shaped.
- FIG. 8 illustrates a plan view of another example of a slit 10 .
- a width Wb on the backmost end 10 b side of the slit 10 is preferably greater than a width Wa on the frontmost end 10 a side of the slit 10 .
- the tensile deformation of the crown portion 3 and the sole portion 4 in the toe-heel direction tends to be larger when the ball is struck as it moves away from the periphery E of the face portion 2 toward the back of the head.
- the main body 100 can be elastically deformed more effectively when the ball is struck, and the decrease in the repulsion performance can be further suppressed.
- the increase in stress near the backmost end 10 b side of the slit 10 can be effectively suppressed and the durability of the main body 100 can be improved.
- one or more slits 10 are provided in the crown portion 3 , in a plan view of the head shown in FIG. 3 , it is preferable that at least one slit 10 is provided within the projection area A 1 of the face member 200 to the back of the head.
- at least one slit 10 is provided within the projection area A 1 of the face member 200 to the back of the head.
- the thick-walled portion 11 includes, for example, an inner thick-walled portion 11 a raised on the hollow portion (i) side.
- the inner thick-walled portion 11 a is raised toward the hollow portion (i) from the inner surface of the reference thick-walled portion 3 a formed by the reference thickness tc of the crown portion 3 .
- the thickness boundary between the inner thick-walled portion 11 a and the reference thick-walled portion 3 a is a virtual boundary defined by a smooth extension of the inner surface of the reference thick-walled portion 3 a to the slit 10 .
- a thickness ta of the inner thick-walled portion 11 a is not particularly limited, it is preferably, for example, equal to or more than 0.5 mm, preferably equal to or more than 1.0 mm, more preferably equal to or more than 1.5 mm, in order to fully demonstrate the stress reduction effect in the region around the slit 10 .
- the thickness ta of the inner thick-walled portion 11 a is, for example, equal to or less than 5.0 mm, preferably equal to or less than 4.0 mm, more preferably equal to or less than 3.0 mm.
- a width TW of the inner thick-walled portion 11 a and the outer thick-walled portion 11 b is not particularly limited, but it is, for example, equal to or more than 1.0 mm, preferably equal to or more than 2.0 mm, more preferably equal to or more than 3.0 mm, in order to fully demonstrate the stress reduction effect in the periphery of the slit 10 .
- the width TW of the inner thick-walled portion 11 a and the outer thick-walled portion 11 b is, for example, equal to or less than 15.0 mm, preferably equal to or less than 12.0 mm, mor preferably equal to or less than 10.0 mm.
- the width TW is measured orthogonally to the edge of the slit 10 , as illustrated in FIG. 9 .
- a cover made of an elastic material such as rubber, plastic, elastomer, etc. may be provided. Such a cover can prevent foreign objects from entering the slits 10 without interfering with the deformation of the main body 100 in any way.
- the coefficient of restitution at the face center of the example was calculated by computer simulation.
- the coefficient of restitution of the golf club head whose face member is made of titanium alloy (Comparative Example 1) and the golf club head whose slits are removed from the Example (Comparative Example 2) are also calculated by the computer simulation in the same way.
- the weight member and sleeve are identical.
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- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Physical Education & Sports Medicine (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Golf Clubs (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2022079499A JP2023167940A (ja) | 2022-05-13 | 2022-05-13 | ゴルフクラブヘッド |
JP2022-079499 | 2022-05-13 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20230364477A1 true US20230364477A1 (en) | 2023-11-16 |
Family
ID=88700166
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US18/140,810 Pending US20230364477A1 (en) | 2022-05-13 | 2023-04-28 | Golf club head |
Country Status (2)
Country | Link |
---|---|
US (1) | US20230364477A1 (ja) |
JP (1) | JP2023167940A (ja) |
-
2022
- 2022-05-13 JP JP2022079499A patent/JP2023167940A/ja active Pending
-
2023
- 2023-04-28 US US18/140,810 patent/US20230364477A1/en active Pending
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Publication number | Publication date |
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JP2023167940A (ja) | 2023-11-24 |
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AS | Assignment |
Owner name: SUMITOMO RUBBER INDUSTRIES, LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OZAKI, YOHEI;HAYASE, SEIJI;ONUKI, MASAHIDE;REEL/FRAME:063494/0862 Effective date: 20230412 |
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STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |