Iron type golf club head

Abstract

To provide an iron type golf club head capable of further improving a repulsion performance on a sole side of a face.SOLUTION: An iron type golf club head 1 comprises: a head main body 10 which has, a face, a top 3, a sole 4, and a face rear face 5; and a plurality of ribs 20 which extends in a head vertical direction on the face rear face 5 side of the head main body 10. The ribs 20 are arranged at intervals in a toe-heel direction. Each rib 20 is provided in a face upper part area which is an upper half area of the head vertical direction at a position where the rib is arranged. The rib 20 is made from a material having relative density smaller than that of a material of the face.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an iron-type golf club head. [Background technology]

[0002] Iron type golf clubs are often used to hit balls placed directly on the grass. For this reason, there is a tendency for iron type golf clubs to frequently hit the ball below (sole side) the geometric center of the face. Therefore, in order to increase the flight distance of a hit ball with an iron type golf club, it is effective to configure the lower side of the face to bend more.

[0003] The following Patent Document 1 describes a golf club head in which a rib extending in the toe-heel direction is formed on the back surface of the face. This golf club head is expected to improve the flexure characteristics in the vicinity of the position where the ball is actually hit (approximately 15 mm above the sole), thereby improving and stabilizing the flight distance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-110974 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the golf club head of Patent Document 1, the rib extending in the toe-heel direction on the back surface of the face inhibits the face from bending in the toe-heel direction when hitting the ball, leaving room for further improvement in terms of increasing the flight distance of the ball.

[0006] The present invention has been devised in consideration of the above problems, and has as its main object to provide an iron-type golf club head which can further improve the repulsion performance on the sole side of the face. [Means for solving the problem]

[0007] The present invention is an iron-type golf club head comprising: a head body having a face, a top, a sole, and a back surface of the face; and a plurality of ribs extending in a head-up / down direction on the back surface side of the face of the head body, the ribs being spaced apart in the toe-heel direction, each of the ribs being located within an upper face region which is the upper half of the up-down length of the face at the position where the rib is located, and the ribs being made of a material having a smaller specific gravity than the material of the face.

[0008] In another aspect of the invention, each of the ribs may be independent of one another and not connected to one another.

[0009] In another aspect of the present invention, the rib may have a thickness of 1 to 10 mm in a direction perpendicular to the face.

[0010] In another aspect of the present invention, the width of the rib in the toe-heel direction may be 1 to 5 mm.

[0011] In another aspect of the present invention, the length of the rib in the vertical direction of the head may be 5 to 20 mm.

[0012] In another aspect of the present invention, each of the ribs may have a length in the head up-down direction that is 60% or more of the face upper region.

[0013] In another aspect of the present invention, a badge may be further provided to cover the rib from a rear side of the head.

[0014] In another aspect of the present invention, an elastic body for absorbing vibrations may be disposed between the badge and the back surface of the face.

[0015] In another aspect of the present invention, the elastic body may be disposed between the rib and the back surface of the face.

[0016] In another aspect of the present invention, the elastic body may be disposed between the rib and the badge. Effect of the Invention

[0017] By adopting the above-described configuration, the iron-type golf club head of the present invention makes the sole side of the face more flexible, and therefore can further improve the repulsion performance when hitting the sole side of the face. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a front view of the iron golf club head of the present embodiment. [Diagram 2] FIG. 2 is a rear view of FIG. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 13 is a rear view of an iron-type golf club head according to another embodiment. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 5. [Figure 7] 7 is a cross-sectional view taken along line VII-VII in FIG. 5. [Figure 8] FIG. 11 is a horizontal cross-sectional view of a head body showing another embodiment. [Figure 9] FIG. 11 is a horizontal cross-sectional view of a head body showing another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, when there are multiple embodiments, the same or common elements are designated by the same reference numerals throughout the specification, and duplicate explanations are omitted.

[0020] FIG. 1 is a front view of an iron-type golf club head (hereinafter simply referred to as "head") 1 of this embodiment, FIG. 2 is a rear view thereof, FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

[0021] 1 and 2, the head 1 is in a forward-leaning state. In this specification, the "forward-leaning state" of the head 1 refers to a state in which the head 1, which is in a reference state, is inclined forward so that its loft angle is zero and is grounded on a horizontal plane HP. Also, the "reference state" refers to a state in which the head 1 is held at a prescribed lie angle and loft angle determined for the head 1 with respect to the horizontal plane HP. In the reference state, the shaft axis center line CL (FIG. 1) is disposed within a reference vertical plane, and the score lines 7 formed on the face 2 of the head 1 are parallel to the horizontal plane HP. In this specification, unless otherwise specified, the head 1 is described as being in a forward-leaning state.

[0022] [Head Orientation] In this specification, when the head 1 is in a forward tilted state, the direction x that is parallel to the horizontal plane HP and perpendicular to the scoreline 7 is defined as the front-to-rear direction of the head. With respect to the front-to-rear direction of the head, the side of the face 2 is defined as the front side, and the opposite side is defined as the rear side (back side). Moreover, the direction y that is parallel to the scoreline 7 is defined as the toe-heel direction. Furthermore, the direction z that is perpendicular to the horizontal plane HP is defined as the up-down direction of the head.

[0023] [Basic head structure] 1 to 4, the head 1 of this embodiment includes a head body 10. The head body 10 includes, for example, a face 2, a top 3, a sole 4, a face back surface 5, a toe 8, and a heel 9. The head body 10 of this embodiment is made of a metal material. The metal material is not particularly limited, but examples of the metal material that can be used include stainless steel, soft iron, etc.

[0024] The head body 10 may be formed by using two or more kinds of metal materials, in addition to being an integrally molded product by casting or the like. In the latter case, the head body 10 may be formed by, for example, fixing a face plate and a face receiving portion, or may be further compounded with a weight member or the like as a separate part.

[0025] The face 2 is a striking surface that strikes a ball. This striking surface is made of a metal material. A plurality of scorelines 7 extending in the toe-heel direction are formed on the face 2. The face 2 of this embodiment provides a striking surface consisting of a single plane except for the scorelines 7. When the head 1 is in a forward-leaning state, the scorelines 7 are parallel to the horizontal plane HP. Note that some of the scorelines 7 are omitted in FIG. 1.

[0026] A face thickness is defined between the face 2 and the face back surface 5. The face thickness can be appropriately determined according to convention, but is preferably 1.0 mm or more, more preferably 1.3 mm or more, and even more preferably 1.6 mm or more so as not to impair durability. On the other hand, the face thickness is preferably 3.0 mm or less, more preferably 2.7 mm or less, and even more preferably 2.4 mm or less so that the face 2 can be sufficiently flexed when hitting the ball. In this embodiment, the face thickness is almost constant, but the sole side of the face 2 close to the actual hitting position may be formed relatively thin.

[0027] The top 3 extends rearward from the face 2 to form the upper surface of the head. In an iron-type golf club head, the top 3 typically slopes obliquely downward from the toe 8 side to the heel 9 side.

[0028] The sole 4 extends from the face 2 toward the rear of the head so as to form the bottom surface of the head.

[0029] The head 1 of this embodiment further includes a hosel 6. The hosel 6 is provided on the heel 9 side of the face 2. The hosel 6 is cylindrical and defines a shaft insertion hole 6a into which a shaft (not shown) is attached. The axial center line of the shaft insertion hole 6a is utilized as the shaft axial center line CL.

[0030] [rib] The head 1 of this embodiment further includes a plurality of ribs 20 extending in the up-down direction of the head on the back surface 5 side of the face of the head body 10. In this embodiment, four ribs 20 are depicted, but it is sufficient that at least two ribs are provided, and preferably three or more ribs.

[0031] The rib 20 has a length L (FIG. 3) in the up-down direction of the head, a width W (FIG. 4) in the toe-heel direction, and a thickness t (FIG. 4) in the direction perpendicular to the face 2. For example, each of the ribs 20 is formed so that its width W is smaller than its length L. This gives the rib 20 an elongated shape in the up-down direction of the head.

[0032] The rib 20 is shown in such a manner that the longitudinal direction of the rib 20 (the direction defined by the straight line connecting both ends of the center line of the width W) extends linearly parallel to the head vertical direction. In another embodiment, the longitudinal direction of the rib 20 may be inclined at an angle of 15 degrees or less with respect to the head vertical direction. In another embodiment, the rib 20 may be bent.

[0033] In addition, the rib 20 in this embodiment is configured to have a quadrangular shape in a cross section perpendicular to the longitudinal direction thereof. In other embodiments, the rib 20 may be configured to have various shapes such as a trapezoid, a triangle, a semicircle, or the like.

[0034] The ribs 20 are arranged at intervals in the toe-heel direction. As a preferred embodiment, the ribs 20 are arranged at a constant pitch P in the toe-heel direction. In another embodiment, the ribs 20 may be arranged at a different pitch P in the toe-heel direction. The formation range of the ribs 20 is, for example, a region C ( FIG. 1 ) in the toe-heel direction where the scorelines 7 of the face 2 are formed, and it is desirable to provide a plurality of ribs 20 within this region C.

[0035] In this embodiment, each rib 20 can be fixed to the back surface 5 of the face by various fixing means, for example, adhesive, double-sided tape, screws, welding, or the like.

[0036] 3, each of the ribs 20 is located within a face upper region A which is the upper half of the vertical length Hi of the face 2 at the position where the rib 20 is disposed. In other words, the lower end of each of the ribs 20 is located so as not to protrude into a face lower region B which is the lower half of the vertical length Hi of the face 2 at the position where the rib 20 is disposed.

[0037] The rib 20 as described above relatively increases the vertical bending rigidity of the face upper region A, making this portion less likely to bend. Here, the "vertical bending rigidity" of the face 2 means the bending rigidity in the direction indicated by the arrow M1 in FIG. 3. The head 1 provided with such a rib 20 can shift the maximum bending position of the face 2 when hitting a ball closer to the sole 4 side than the geometric center point of the face. This helps to improve the bending characteristics near the hitting position (near the height of 15 mm from the sole) where balls are actually hit frequently.

[0038] Furthermore, the degree of deflection of the face 2 when hitting a ball is affected not only by the bending rigidity in the vertical direction but also by the bending rigidity in the toe-heel direction. Here, "bending rigidity in the toe-heel direction" means bending rigidity in the direction shown by arrow M2 in Fig. 4. The ribs 20 of this embodiment extend in the up-down direction of the head and are arranged at intervals in the toe-heel direction, so they do little to increase the bending rigidity in the toe-heel direction of the face upper region A.

[0039] Therefore, in the head 1 of the present embodiment, the sole side of the face 2 is made more flexible, and the repulsion performance upon impact with the sole side of the face 2 can be further improved.

[0040] Furthermore, the rib 20 of this embodiment is made of a material having a smaller specific gravity than the material of the face 2. Therefore, the rib 20 does not excessively raise the head center of gravity. Therefore, the head 1 of this embodiment can maintain the sweet spot low and move it closer to the actual hitting position of the ball, thereby further increasing the flight distance. In a preferred embodiment, the height of the sweet spot from the horizontal plane is, for example, 25 mm or less, more preferably 23 mm or less, and even more preferably 21 mm or less.

[0041] The material for forming the rib 20 is not particularly limited as long as it has a lower specific gravity than the material for forming the face 2, and may be, for example, a metal material, a resin, a composite material thereof, or the like. Suitable metal materials include, for example, titanium, aluminum, magnesium, or alloys thereof. Suitable resin materials include, for example, thermoplastic resins such as polyvinyl chloride, polyethylene, polypropylene, polycarbonate, and polyamide, and thermosetting resins such as phenol resin, epoxy resin, and unsaturated polyester resin. The rib 20 may also be made of, for example, a fiber-reinforced resin that is a composite of fiber and resin.

[0042] In a preferred embodiment, the ribs 20 are arranged independently of each other without being connected to each other as in this embodiment. That is, adjacent ribs 20 are only indirectly connected to each other via the face back surface 5, and are not directly connected to each other. Such a rib structure is useful for increasing the bending rigidity of the face 2 in the vertical direction, while further reducing the bending rigidity in the toe-heel direction.

[0043] The thickness t of the rib 20 in the direction perpendicular to the face is desirably, for example, 1 to 10 mm. By making the thickness t of the rib 20 1 mm or more, the bending rigidity in the vertical direction of the face upper region A can be increased. Furthermore, by making the thickness t of the rib 20 10 mm or less, the center of gravity of the head 1 can be kept low. Particularly preferably, the thickness t of the rib 20 is, for example, 1.5 mm or more, more preferably 2.0 mm or more, and, for example, 7 mm or less, more preferably 4 mm or less.

[0044] The width W of the rib 20 in the toe-heel direction is desirably, for example, 1 to 5 mm. By making the width W of the rib 20 1 mm or more, the vertical bending rigidity of the face upper region A can be increased. Furthermore, by making the width W of the rib 20 5 mm or less, the center of gravity of the head 1 can be kept low. In particular, the width W of the rib 20 is preferably, for example, 2 mm or more, more preferably 2.5 mm or more, and, for example, 4.5 mm or less, more preferably 4 mm or less.

[0045] The length L of the rib 20 in the head up-down direction is desirably, for example, 50% to 100% of the face upper region A. By making the length L of the rib 20 50% or more of the face upper region A, the effect of improving the vertical bending rigidity of the face upper region A can be sufficiently exhibited. Furthermore, by making the length L of the rib 20 100% or less of the face upper region A, the center of gravity of the head 1 can be kept low. Particularly preferably, the length L of the rib 20 is, for example, 55% or more, more preferably 60% or more, and, for example, 90% or less, more preferably 80% or less of the face upper region A. Furthermore, the lengths of the ribs 20 may be the same or different.

[0046] The upper end of each rib 20 is desirably located at the uppermost part of the back surface 5 of the face. In the head 1 of this embodiment, a cavity is formed on the top 3 side, and the rib 20 enters therein and is located at the uppermost part of the back surface 5 of the face. On the other hand, the position of the lower end of each rib 20 is appropriately determined according to the length L. For example, the lower ends of each rib 20 may be provided at the same position in the vertical direction of the head.

[0047] The ribs 20 may also be defined in relation to the length of each of the face upper regions A. For example, each of the ribs 20 may have a length L that is 60% or more, more preferably 70% or more, and even more preferably 80% or more of the length of each of the face upper regions A. This allows the ribs 20 to effectively increase the vertical bending rigidity of the face upper region A at each position, and provide a large deflection to the face lower region B when the ball is hit on the sole side.

[0048] The pitch P of the rib 20 in the toe-heel direction is not particularly limited, but in order to suppress the vertical deflection of the face upper region A while suppressing an increase in weight of the head 1, it is, for example, 5 mm or more, preferably 10 mm or more, and more preferably 20 mm or more, and for example, 50 mm or less, preferably 45 mm or less, and more preferably 40 mm or less.

[0049] [Other embodiments] Next, a head 1 of another embodiment will be described. Fig. 5 is a rear view of the head 1 of the other embodiment, Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5, and Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 5. As shown in Figs. 5 to 7, this embodiment differs from the previous embodiment in that a badge 30 is further provided to cover the rib 20 from the rear of the head. The badge 30 of this embodiment covers all of the ribs 20. In another embodiment, the badge 30 may cover only a portion of the rib 20.

[0050] The badge 30 of this embodiment is, for example, a thin plate made of resin or metal. For example, a logo mark or a decorative pattern may be formed on the back surface of the badge 30 (the surface visible in FIG. 5). The badge 30 is useful for improving the appearance of the head 1.

[0051] The badge 30 is fixed, for example, to the back surface of the rib 20 (the surface opposite to the face 2) via an adhesive or the like. In the head 1 of the present embodiment, the rib 20 is entirely covered with the badge 30, and therefore is protected from impacts, and thus its durability is improved.

[0052] 6 and 7, in this embodiment, an elastic body 40 for absorbing vibrations is disposed between the badge 30 and the face back surface 5. The elastic body 40 has a function of absorbing vibrations that occur when the ball is struck with the face 2. Therefore, the head 1 of this embodiment is useful for giving the golfer a good shot feeling.

[0053] 7, the elastic body 40 of this embodiment fills the space surrounded by the face back surface 5, the rib 20, and the badge 30, and is in contact with not only the face back surface 5 but also the rib 20 and the badge 30. Such an elastic body 40 serves to more effectively dampen the vibration of the face 2 when hitting the ball, and to provide a better hitting feel.

[0054] The material constituting the elastic body 40 is preferably an elastic body such as resin, rubber, or elastomer.

[0055] Fig. 8 shows a horizontal cross-sectional view of the head body 10 as yet another embodiment. As shown in Fig. 8, the front surface (the face 2 side) of the rib 20 is separated from the face back surface 5. In this embodiment, an elastic body 40 is disposed between the rib 20 and the face back surface 5. If the distance G1 between the rib 20 and the face back surface 5 becomes large, there is a risk that the effect of suppressing the vertical deflection of the face upper region A will decrease, and therefore, it is desirable that the distance G1 be, for example, 2 mm or less, more preferably 1 mm or less.

[0056] Fig. 9 shows a horizontal cross-sectional view of the face 2 as yet another embodiment. As shown in Fig. 9, the front surface (the face 2 side) of the rib 20 is separated from the face back surface 5. The rear surface (the side opposite to the face 2) of the rib 20 is also separated from the badge 30. In this embodiment, an elastic body 40 is disposed between the rib 20 and the face back surface 5 and between the rib 20 and the badge 30. If the distance G2 between the rib 20 and the badge 30 becomes large, the effect of suppressing the vertical deflection of the face upper region A may decrease, so the distance G2 is desirably, for example, 4 mm or less, more desirably 2 mm or less.

[0057] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above specific disclosure, and can be implemented in various modified forms within the scope of the technical ideas described in the claims. EXAMPLES

[0058] In order to confirm the effects of the present invention, more detailed examples of the present invention will be described. However, the present invention is not limited to these examples.

[0059] [Example] An iron-type golf club head (#7) having the basic structure of Figures 1 to 4 and having three ribs made of CFRP (material) extending in the vertical direction of the head arranged on the back surface of the face of the head body made of stainless steel was prototyped based on the specifications in Table 1, and its repulsion performance was tested by simulation (Example).

[0060] [Comparative Example] For comparison, an iron-type golf club head having the same head body as the embodiment except for the rib (Comparative Example 1) and an iron-type golf club head having a rib extending in the toe-heel direction made of the same material as the rib (Comparative Example 2) were prepared and similarly evaluated for resilience performance. The rib in the toe-heel direction was located 30 mm above the sole.

[0061] [Rebound performance] As the repulsion performance, COR was measured. COR stands for Coefficient of Restitution. COR was measured based on the "Interim Procedure for Measuring the Coefficient of Restitution of an Iron Clubhead Relative to a Baseline Plate Revision 1.3 January 1, 2006" stipulated by the USGA (United States Golf Association). The higher the COR value, the better the repulsion of the face at the measurement position (the greater the deflection).

[0062] COR values ​​were measured at three locations: Center-lower hitting position: The center of the longest score line in the toe-heel direction and 15 mm above the ground Toe side impact position: 15mm shifted from the center bottom impact position toward the toe side Heel side impact position: 10mm offset from the center bottom impact position toward the heel side The test results are shown in Table 1.

[0063] [Table 1]

[0064] As a result of the test, it was confirmed that the head of the embodiment exhibited high resilience not only at the lower center hitting position, but also at the toe side hitting position and the heel side hitting position. [Explanation of symbols]

[0065] 1 Head 2 Face 3 Top 4 Sole 5 Back of face 10 Head body 20 Ribs 30 Badges 40 Elastic Body A Upper Face Area

Claims

1. An iron-type golf club head, a head body having a face, a top, a sole, and a face back surface; and a plurality of ribs extending in a head up-down direction on the face back surface side of the head body, The ribs are spaced apart in a toe-heel direction, Each of the ribs is located within a face upper region that is an upper half region of the face in the up-down direction at the position where the rib is disposed, the rib is made of a material having a lower specific gravity than a material of the face; the top extends from the face to the rear of the head so as to form an upper surface of the head, and extends further rearward than the back surface of the face, An upper end of each of the ribs is located at the uppermost part of the back surface of the face so as to contact the top, Each of the ribs has a length in the head up-down direction that is 60% or more of the face upper region. Iron type golf club head.

2. 2. The iron-type golf club head according to claim 1, wherein each of said ribs is independent of one another and not connected to one another.

3. 3. The iron-type golf club head according to claim 1, wherein the thickness of said rib in a direction perpendicular to said face is 1 to 10 mm.

4. 4. The iron-type golf club head according to claim 1, wherein the width of said rib in the toe-heel direction is 1 to 5 mm.

5. 5. The iron-type golf club head according to claim 1, wherein the length of said rib in the vertical direction of the head is 5 to 20 mm.

6. 6. The iron-type golf club head according to claim 1, wherein the lower ends of the ribs are positioned so as not to extend into a face lower region B which is a lower half region of the face having a vertical length Hi at the position where each rib is disposed.

7. 7. The iron-type golf club head according to claim 1, further comprising a badge covering said rib from a rear side of the head.

8. 8. The iron-type golf club head according to claim 7, further comprising an elastic body for absorbing vibrations disposed between said badge and said back surface of said face.

9. 9. The iron-type golf club head according to claim 8, wherein the elastic body is disposed between the rib and the back surface of the face.

10. 10. The iron-type golf club head according to claim 8, wherein the elastic body is disposed between the rib and the badge.

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