JP2002065911A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a soft hitting-touch. SOLUTION: The golf club head 1 has a face surface 2 striking a ball formed out of a metal material. The face surface 2 has a coarse face part 45 formed by making abrasive grains, made of ceramics with the average size of 0.3 to 2.0 mm, impinge onto the face surface 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a golf club head capable of improving the feel at impact.

[0002]

2. Description of the Related Art Professional golfers, intermediate golfers, and advanced golfers attach great importance to the feeling of hitting, which is the feeling or feeling transmitted to the hand at the moment of hitting a ball with a golf club. In particular, in the case of an iron type golf club, a soft feel at impact is preferred so as to serve as a guide for properly separating the flight distance. Performance such as the hardness of the ball is strongly related to the feel at impact, but it has been found that different feels can be obtained depending on the club head even when the same ball is hit. Conventionally, in order to obtain a soft feel at impact, for example, using a relatively soft material for the face portion hitting the ball, for example, using a metal material such as fiber reinforced resin or soft iron, or without plating the surface of the face portion Although they are used, they are not yet sufficient, and further improvement in shot feeling is desired.

[0003] The inventors of the present invention have conducted intensive studies in order to obtain a softer feel at impact on the premise that a golf club head in which a ball hitting face is formed of a metal material, and as a result, the face has an average particle size By providing a rough surface formed by injecting and colliding ceramic abrasive grains of 0.3 to 2.0 mm, it is surprisingly found that a very soft shot feeling can be obtained, and completed the present invention. It is.

Conventionally, abrasive grains have been made to collide with the surface of the face portion in shot blasting, shot peening, or the like (for example, see Japanese Patent Laid-Open No. 10-1).
No. 79824). However, this method mainly improves the appearance of the face portion by colliding a metal ball with the face portion surface, and rounds the edge of the face groove formed on the face portion surface to cause damage to the ball. This is fundamentally different from the technical problem of the present invention in that the object is to suppress the above. In addition, in connection with such a difference in technical problems, the above publication is limited to metal balls, and does not suggest the configuration of the present invention using ceramic abrasive grains.

[0005] As described above, an object of the present invention is to provide a golf club head capable of obtaining a soft feel at impact based on the provision of the above-described rough surface portion on the face portion.

[0006]

SUMMARY OF THE INVENTION The present invention is a golf club head in which a face for hitting a ball is formed of a metal material, wherein the face has an average particle diameter of 0.3 to 0.3.
It is characterized by having a rough surface portion formed by colliding 2.0 mm ceramic abrasive grains with the face surface.

The rough surface portion can be formed, for example, by colliding the abrasive grains with a face surface in which a face groove extending in the toe and heel directions is formed in advance. Preferably, at least a part of the rough surface portion is made of a titanium alloy.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of an iron-type golf club head, and FIG. 2 is a partially enlarged cross-sectional view perpendicular to the face surface. As shown in the figure, a golf club head (hereinafter, may be simply referred to as a “head”) 1 of the present embodiment is formed integrally with a head body 1a and a heel h side of the head body 1a. And a shaft mounting portion 1b to which a shaft not to be mounted is mounted.

In this embodiment, an example in which the entire head 1 is made of a metal material is illustrated. As the metal material, for example, carbon steel, stainless steel, titanium, a titanium alloy, and other materials are used. In this example, the head main body 1a includes a face plate 1a1 made of a titanium alloy of Ti-6Al-4V, A face plate 1a1 and a face receiving portion 1a2 arranged on the front surface are shown, and the surface of the face plate 1a constitutes a main portion of a face 2 on which a ball is hit. The face receiving portion 1a2 is made of a metal material such as soft iron or stainless steel having a specific gravity larger than that of the face plate 1a1 to increase the moment of inertia of the head.

In the present embodiment, the face surface 2 is provided with vertical lines L1 and L2 extending substantially vertically on the toe t side and the heel h side, respectively, and an approximate hitting area is visually defined between them. . Then, between the vertical lines L1 and L2, when the head 1 is placed on a horizontal surface in accordance with the prescribed lie angle and loft angle, the toe t,
An example is shown in which the face groove 3 extending in the heel h direction, that is, substantially horizontally, is recessed. The face groove 3 plays an important role in, for example, increasing the frictional force with the ball when hitting the ball on the face surface 2 and giving spin to the ball. In this example, as shown in FIG. In the cross section perpendicular to 2, the cross section is illustrated as having a substantially triangular shape.

The face groove 3 has a groove width GW of 0.9 mm or less according to the golf rules of the Japan Golf Association.
The groove depth GD is specified as 0.5 mm or less. The head 1 of the present embodiment has a face groove 3 conforming to this rule, for example, a groove width GW of 0.5 to 0.9 mm and a groove depth GD
Is set at 0.3 to 0.5 mm. The groove length of the face groove 3 can be variously determined according to the shape of the face surface 2.
Such a face groove 3 can be recessed by various methods using, for example, a convex portion of a mold, or a press, a cutting tool, or the like.

Further, in this embodiment, the face surface 2 on which the face grooves 3 are formed in advance has an average particle size of 0.3 to 2.0.
The head 1 is manufactured by providing a rough surface portion 4 formed by colliding a 0 mm ceramic abrasive grain with the face surface 2. The rough surface portion 4 of this example is formed in a region surrounded by the vertical lines L1 and L2, the upper edge 2a of the face surface 2, and the lower edge 2b of the face surface 2, and the ball is hit normally. In such a case, the ball is formed so as to be able to reliably contact the rough surface portion 4. As a result of various experiments by the inventors, the head 1 having such a rough surface portion 4 was obtained.
Found that a very soft feel at impact was obtained when hitting the ball.

As shown in FIG. 2, the abrasive grains impinge on the face surface 2 on which the face grooves 3 are formed in advance as in the present embodiment, so that the groove walls 3a of the face grooves 3 are formed.
The edge portion 3b where the face 3 intersects with the face 2 can be rounded by abrasive grains, thereby preventing the ball from being damaged. When the face groove 3 is formed at the time of casting, for example, the face surface 2 is polished first to eliminate the so-called “slump” of the face groove 3, and then the abrasive grains are caused to collide with the face surface 2. The edge portion 3b
Is desirable. The face groove 3 is pressed,
In the case of being formed by cutting or the like, it is preferable since the burr formed on the edge of the face groove 3 can be removed at the same time when the rough surface portion 4 is formed.

In the present invention, the shape of the abrasive grains used to form the rough surface portion 4 is not particularly limited. For example, a so-called shot made of a substantially spherical small iron ball as shown in FIG. Abrasive materials such as non-spherical grids having sharp portions as in (A) are preferably used.
It is also possible to use species or a mixture of two or more species.
Further, the abrasive grains need to be made of ceramics. Here, the ceramic is a solid composed of an inorganic nonmetallic substance, and more preferably a sintered body obtained by molding and firing an inorganic powder. The abrasives used in the present invention include, among ceramics,
In particular, those using high-purity artificial raw materials such as new ceramics or fine ceramics are desirable. More specifically, examples include alumina ceramics, silicon carbide ceramics, silicon nitride ceramics, zirconia ceramics, isotropic high-density high-purity graphite, and the like. Examples of the alumina ceramics include abrasive materials such as brown alumina, white alumina, light red alumina, crushed alumina, artificial emery, and alumina zirconia.Examples of silicon carbide ceramics include black silicon carbide and green An abrasive material such as silicon carbide can be used. Among them, the above-mentioned alumina ceramics, which have a high surface hardness and a high toughness and have a long abrasive life, are particularly desirable.

The abrasive preferably has a specific gravity of 3.0.
-4.5, more preferably 3.5-4.0. If the specific gravity exceeds 4.5, for example, it becomes difficult to fly with the air pressure at the time of shot blast, and it is not possible to give a sufficient acceleration force to the abrasive grains. The kinetic energy when colliding with the surface is small, and the effect of roughening the surface is low. Such ceramic abrasive grains have excellent durability and high surface strength, and have a specific gravity smaller than that of metallic abrasive grains. The rough surface portion 4 can be formed by the collision, and the forming efficiency of the rough surface portion 4 can be increased.

In the present specification, the “average particle size” of the abrasive grains means that a plurality of types of meshes having a mesh of 0.1 mm are prepared, the abrasive grains are passed through the respective meshes, and the passing rate at that time. Is determined by weighted average based on For example, the passage rate of the abrasive grains is 97% or more with a mesh of X mm mesh, 5% with the same (X-0.1) mm, 80% with the same (X-0.2) mm, and (X-0.3 ) Mm and 10%, (X-0.
4) When 5% in mm and less than 3% in (X-0.5) mm,
The average grain size of the abrasive grains is {(X-0.1) + X} × 0.05 / 2 + {(X-0.
2) + (X-0.1)｝ × 0.8 / 2 + ｛(X-0.
3) + (X-0.2)｝ × 0.1 / 2 + ｛(X-0.
4) + (X−0.3)｝ × 0.05 / 2. Note that, as described above, the maximum and the minimum of the mesh have a 3% tolerance.

If the average grain size of the abrasive grains is smaller than 0.3 mm, sufficient roughness cannot be given to the rough surface portion 4 and the shot feeling cannot be made soft and mild. On the other hand, if the average grain size of the abrasive grains exceeds 2.0 mm, the rough surface portion 4 becomes too rough, so that it becomes difficult to obtain a mild shot feeling, and the ball is easily damaged, and the face surface 2 Marks of the ball are likely to stick. From such a viewpoint, the average particle diameter of the abrasive grains is more preferably 0.3 to 1.5 m
m, more preferably 0.3 to 1.0 mm.

As a method of causing the abrasive grains to collide with the face surface 2, various methods such as sand blasting, shot peening, grit blasting, and liquid honing are known. In the present invention, any of these methods is used. It can be performed using: The abrasive grains are accelerated by any means such as gas, liquid, or centrifugal force and are ejected toward the face surface 2 and collide with the face surface 2.
The rough surface portion 4 can be formed on the substrate. As an example, in a direct pressure blast machine that accelerates and jets abrasive grains using high-pressure air,
For example, 0.2 to 0.9 MPa, more preferably 0.4
The air pressure is set to about 0.6 MPa.
The collision is desirably performed for 00 seconds, more preferably for 40 to 120 seconds. If the air pressure is too low or the injection time is too short, the rough surface portion 4 cannot be formed with sufficient roughness, and the shot feeling tends not to be improved, and conversely, the air pressure is too high, or If the injection time is too long, the roughness tends to be too large and the shot feeling tends not to be improved.

In particular, such abrasive grains made of ceramics having a high surface hardness collide with the face surface 2 having a titanium alloy such as Ti-6Al-4V, so that even a titanium alloy having a high surface hardness has a particularly good shot feeling. Can provide a mild head 1. Further, when the groove width GW of the face groove 3 is formed to be larger than the average particle diameter of the abrasive grains, the abrasive grains collide with the groove walls 3a of the face grooves 3, and the groove walls 3a
An uneven surface is formed on the surface. If such an uneven surface is formed on the groove wall 3a, for example, the brightness of the groove wall 3a of the face groove 3 is lost, and the appearance tends to deteriorate. In order to solve such a problem, the face groove 3 may be recessed after the rough surface portion 4 is formed on the face surface 2, but in this case, the edge portion 3b of the face groove 3 becomes sharp. , The ball tends to be easily scratched.

For this reason, for example, the groove width GW and the groove depth GD of the face groove 3 are both smaller than the average particle diameter of the abrasive grains, and the abrasive grains collide with the face surface 2 so that the rough surface portion 4 is formed. At the time of formation, an improvement can be made so that abrasive grains do not substantially collide with the groove walls 3 a of the face grooves 3 formed in advance on the face surface 2. Thereby, the face groove 3
Of the face groove 3 can be prevented from being deteriorated, and at the same time, the edge portion 3b can be appropriately rounded to prevent the ball from being damaged. .

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An iron-type golf club head (# 3, # 5, # 7, # 9, P) having the same shape as shown in FIG.
W, AW, SW) were prototyped, and a rough steel portion was formed by colliding a spherical steel shot against the face surface at an air pressure of 0.6 MPa for 20 seconds. Each face groove has a groove width of 0.
8 mm and a groove depth of 0.4 mm were formed at the time of casting. Table 1 shows the specifications of the abrasive grains having a rough surface portion formed on each head.

[0022]

[Table 1]

Each of the abrasive grains was caused to collide with the face surface for 50 seconds at an air pressure of 0.6 MPa using an ascon blast cabinet (model BA-I type direct pressure type) manufactured by Atsushi Tekko Co., Ltd. A shaft is attached to each head to manufacture an iron-type golf club, and a handicap 20
A test hit test was conducted with the following six golfers,
The launch angle of the ball and the amount of back spin were examined. With respect to the feel at impact, a tester of an advanced golfer out of six randomly selected handicap players with a handicap of 20 or less was given a test hit, and evaluated on a 5-point scale, and the average value is shown. The larger the value, the softer the shot feeling and the better the feeling. Table 2-3 shows the test results
Shown in

[0024]

[Table 2]

[0025]

[Table 3]

As a result of the test, the example of the embodiment is a conventional example,
It can be confirmed that the shot feeling is softer than in the comparative example and the backspin amount is sufficiently obtained. Further, as shown in Japanese Patent Application Laid-Open No. H11-253584 previously proposed by the present applicant, the head of the example has a lower backspin in the so-called long iron and middle iron having a lower loft angle than the head of the comparative example. It was confirmed that the state was obtained and the launch angle was large, which was useful for improving the flight distance. In addition, a short iron having a large loft angle has an increased backspin amount, and can provide a club having excellent control performance.

Next, in the head, a rough surface portion is formed by keeping the width of the face groove (square groove) constant at 0.8 mm and the groove depth at 0.4 mm, and changing the average particle diameter of the abrasive grains variously. In addition, a test was performed to measure the radius of curvature of the edge of the face groove and the appearance of the groove wall of the face groove. The results are shown in Table 4. In the case of the example, the edge of the face groove was sufficiently rounded, and the groove wall was not substantially formed with irregularities. It was also confirmed that the appearance of the face groove could be improved while preventing the appearance of the face groove.
The radius of curvature of the edge portion is, as shown in FIG. 4, a cross section passing through the middle position of the vertical line, the intersection A between the virtual extension line V1 of the face surface and the face groove, the virtual extension line V2 of the groove wall and the edge. The radius R of the arc passing through the intersection B of the portion and the intersection C of the straight line V3 inclined at 45 ° with respect to the face surface and the edge C was measured.

[0028]

[Table 4]

[0029]

As described above, according to the first aspect of the present invention, the face surface is formed by colliding abrasive grains made of ceramics having an average particle diameter of 0.3 to 2.0 mm against the face surface. By providing the rough surface portion, a very soft feel at impact can be obtained, and in particular, a golf club head that is easy to use for professionals and advanced users can be provided.

When the rough surface is formed by colliding the abrasive grains with the face surface in which the face grooves are formed in advance as in the second aspect of the present invention, smooth processing is performed by rounding the groove edges of the face grooves. This can prevent the ball from being damaged.

Further, since at least a part of the rough surface portion is made of a titanium alloy, a very soft shot feeling can be obtained even with a titanium alloy having a high surface hardness. become.

[Brief description of the drawings]

FIG. 1 is a front view illustrating an example of a head according to an embodiment.

FIG. 2 is an enlarged sectional view showing the face groove.

FIGS. 3A and 3B are schematic diagrams illustrating abrasive grains.

FIG. 4 is a schematic view showing a method for measuring a radius of curvature of an edge portion of a face groove.

[Explanation of symbols]

 Reference Signs List 1 golf club head 2 face surface 3 face groove 4 rough surface portion

Claims (3)

[Claims] 1. A golf club head in which a face for hitting a ball is formed of a metal material, wherein said face is made of ceramic abrasive grains having an average particle diameter of 0.3 to 2.0 mm. A golf club head comprising a rough surface portion formed by colliding with a surface. 2. The method according to claim 1, wherein the rough surface portion is formed by colliding the abrasive grains with a face surface in which a face groove extending in the toe and heel directions is formed in advance.
The golf club head as described. 3. The golf club head according to claim 1, wherein at least a part of the rough surface portion is made of a titanium alloy.