JP2003038690A - Golf club head and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club head having a metallic face of sufficient strength changed in thickness. SOLUTION: The golf club head has the face 10 formed with a thick section 10a and a thin section 10b by forging a metallic sheet subjected to rolling.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a golf club head and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in a golf club head made of metal, it is possible to improve the directionality of a hit ball by increasing the moment of inertia, and to improve the flight distance with a high-resilience hit ball by thinning the face. Are known. Also,
With regard to such a face, partially increasing the strength,
Golf clubs equipped with a golf club head partially provided with a thick portion and a thin portion in order to partially increase the repulsion and to make the stress of the face uniform against impacts are actually sold. No. 9-168613, JP-A-10
-137372, JP-A-9-192273 and the like.

[0003]

However, the metal face of the conventional golf club head whose wall thickness is changed is cast or forged from a metal lump (round bar). In this case, when a metal face having a changed wall thickness is created by casting, the metal structure becomes coarse, voids are likely to occur, and strength is likely to be uneven. In addition, when the metal ingot is manufactured by forging, the metal structure is largely plastically deformed, so that the metal structure becomes dense, but the density is not stable and the density of the structure becomes uneven. Moreover, since it is usually manufactured by hot forging, the characteristics of the material change, and the durability strength also decreases.

As described above, the conventional metal face manufactured by casting or forging and having a varied wall thickness has a problem that the strength is uneven and breakage easily occurs.

The present invention has been made on the basis of the above problems, and a golf club head having a metal face having a sufficient strength with a changed wall thickness, and a golf club head having such a metal face. The purpose is to provide a method.

[0006]

In order to solve the above problems, the golf club head of the present invention is provided with a face having a thick portion and a thin portion formed by forging a rolled metal plate. And Further, in order to solve the above problems, the method for manufacturing a golf club head of the present invention is a method of manufacturing a golf club head having a metal face in which a thick portion and a thin portion are formed. The plate is forged to form a face having a thick portion and a thin portion.

As described above, in the golf club head according to the present invention, the face is made of a metal plate which is previously rolled, and by forging this, a thick portion and a thin portion are formed in the face portion. To be done.

[0008]

1 to 3 are views showing a first embodiment of a golf club head according to the present invention. FIG. 1 is a front view, FIG. 2 is a plan sectional view, and FIG. FIG. 4 is a side sectional view.

A golf club head (hereinafter referred to as a head) 1 according to this embodiment is formed in a hollow shape by fixing a face 10 to an opening portion of a head main body 5 by, for example, welding. Is indicated by the symbol A). In this embodiment, the head body 5 is made of a titanium alloy (Ti-6Al-
4V), and a face 10 formed as will be described later is fixed to its opening.

The head body 5 is composed of an outer shell member including a top 5a, a sole 5b, a toe 5c, a heel 5d, and a back 5e, which are integrally formed by casting (forging or pressing. May be). in this case,
Each outer shell member may be formed individually, or arbitrary members (for example, toe, heel, back) may be integrally formed, and these separate outer shell members may be integrated by welding or the like. The head body 5 is formed by slicing.

A hosel 7 is formed on the top 5a, and a shaft (not shown) is inserted into and fixed to a shaft hole 7a of the hosel.

In the present embodiment, the face 10
The peripheral area (area surrounded by the dotted line in FIG. 1) 10a of the central sweet spot S is formed thick (thick portion 10a), and the area from the periphery to the edge is formed thin. (Thin portion 10b). In this case, face 1
0 is a β-based titanium alloy (for example, Ti-15Mo-5Zr-3Al, Ti-15M, etc.) according to the manufacturing method described later.
o-5Zr-4V-4Al) rolled plate is forged,
It is formed by being plastically deformed to have the above-mentioned shape.

Although the positions where the thick portion and the thin portion are formed are arbitrary, as described above, the thickness of the face 10 is
By thickening the center side where the hit ball concentrates, it becomes difficult to be damaged by the impact at the time of hitting, and by thinning the peripheral side, the shot feeling is soft and the rebound is good and the flight distance The configuration can be improved.

By the way, in the rolled plate obtained by rolling the material as described above, the crystal grains of the material are made fine, and the rolled plate is oriented in the rolling direction as a whole. The arrow direction in FIG. 1 indicates such a rolling direction (a direction in which the crystal grains of the metal structure are elongated). That is, when the face is rolled in the top / sole direction, the long crystal grains are oriented in the top / sole direction.

On the other hand, when the face is bent due to the impact at the time of hitting a ball,
Since the face is formed to have a width in the toe-heel direction larger than that in the top-sole direction, the bending of the flexure becomes tighter in the top-sole direction than in the toe-heel direction. Therefore, a normal face is prone to crack and break along the toe-heel direction near the sweet spot where the hit points are concentrated, but as described above, the long crystal grains are oriented in the top-sole direction. Top
The strength in the sole direction is increased, and it is possible to prevent cracks from being caused by the bending of the tight deflection. Further, even if the thick portion and the thin portion are formed at the positions as described above, since the metal structure is dense and has little unevenness due to rolling, sufficient strength is obtained in addition to the above effect. Will be obtained.

Regarding the thick and thin parts of the face,
If there is a sudden change in thickness between the two, stress tends to concentrate. Therefore, as shown in FIG. 2 and FIG.
It is preferable that the shape of 0a and the thin portion 10b be smoothly continuous.

According to the above face structure, the strength can be improved as compared with the conventional one formed by casting.
The thickness of the thick portion 10a is in the range of 2.0 to 3.0 mm,
The thin portion 10b can be formed to have a wall thickness in the range of 1.3 to 2.5 mm.
When formed of a titanium-based alloy, the thickness of the thick portion 10a is
The thickness of the thin portion 10b is about 2.0 to 2.7 mm and is 1.
It can be formed with a thickness of about 3 to 2.2 mm. In this case, the score line groove formed on the ball striking face side and the rib inside the face (for example, the height is 0.3 mm or less)
Is not the thickness of the thin or thick part.

Actually, the rolled plate before forging which is a face material is 4.5 mm or less, preferably 3.0 mm or less (1.
(0 mm or more), a general face has a wall thickness of 3.0 mm or less, which makes it possible to reduce plastic deformation during forging.

FIG. 4 is a front view showing a second embodiment of the golf club head according to the present invention. In the head of this embodiment, the rolling direction of the face 20 is the top-sole direction, but the thick portion 20 on the center side of the face is used.
It is plastically deformed so as to spread outward when the periphery of a is forged and thinned. For this reason, the center side, which is not plastically deformed, remains as a thick part as it is,
The long direction of the crystal grains is the same as the top-sole direction at the time of rolling, but the long side of the crystal grains is changed to the peripheral direction (radial direction) on the peripheral side when forming the thin portion.

According to such a face structure, since the long crystal grains are oriented in a direction intersecting with the direction of the edges around the face, the edges (top edge E1, leading edge E2, toe side edge E3, heel side edge E4) are formed. )
It is possible to effectively prevent cracks along the line.

Although not shown, the crystal grains may have random directions depending on the forging method around the face, but the present invention includes such a structure. In this case, it is preferable that the long direction of the crystal grains is directed in a constant direction (top / sole direction) at least on the center side of the thick portion where the pressing force for forging is not applied so much as in rolling.

Next, in manufacturing the above golf club head, the manufacturing process of the face portion fixed to the head body will be described with reference to FIGS. The head body is made by welding each outer shell member as described above, and the face fixed to the head body is manufactured as follows.

As shown in FIG. 5, the face 10 described above is used.
Is first formed by punching a rolled metal plate 30 of β-type titanium alloy with a chain double-dashed line. In this case, the direction indicated by the arrow indicates the rolling direction when forming the rolled metal plate 30, and the thickness is 4.5 mm or less, preferably 3.0 mm.
It has been rolled to an extent of less than mm. Therefore, the face material F punched from here is in a state in which the long crystal grains are oriented along the rolling direction,
This direction directly corresponds to the top / sole direction.

The above-mentioned rolling direction is the final rolling direction when rolling is performed a plurality of times. The rolling direction is
In the case of the top-sole direction, it is preferably 0 ° with respect to the designated direction, but may be within a predetermined angle (within ± 30 °) at which the above-described operational effects are sufficiently exhibited.

Next, the punched face material F is shown in FIG.
It is arranged between the molds (upper mold 33, lower piece 35) shown in FIG. In this case, the upper die 33 has a face pressing portion 33a formed in a concave shape whose central side is deepest, and the central portion forms a thick portion. Also,
The lower die 35 has a recess 35a having a dimension slightly wider than that of the face material F, which is a space for plastic deformation, and has generally the same depth, and the face material F is mounted in the recess 35a. Then, it is pressed against the upper mold 33 described above.

FIG. 7 shows a state in which the upper die 33 is pressed against the lower die 35 and the face material F is plastically deformed by forging to thin the periphery of the face material. At this time,
The upper mold 33 also presses the center side of the face material, but since the pressing amount at that part is small, a thick portion is formed,
Since the amount of pressure around the face is large, a thin portion is formed. Therefore, at least at the center side of the face material F, the direction of the crystal grains by the above-mentioned rolling is maintained.

FIG. 8 is a perspective view of the face 10 formed by the steps of FIGS. 5 to 7 as viewed from the back side. In the figure, the ridgeline indicating the thickness change in the toe / heel direction is indicated by X, and the ridgeline indicating the thickness change in the top / sole direction is indicated by Y so that the change in the thickness can be seen, and the arrow indicates the rolling direction. (Long direction of crystal grains) is shown.

According to the above-described manufacturing process, the face material which is initially rolled has a dense and less uneven metal structure, which is punched out and then pressed by the die to forge, which results in a large size. No plastic deformation occurs.
Therefore, it is possible to easily manufacture a face having a thick portion and a thin portion and having sufficient strength (a golf club head having such a face fixed thereto).

Moreover, according to the above-mentioned manufacturing process, since the plastic deformation on the center side where a large number of balls are hit is small,
A metal structure is maintained by the rolling process in the sole direction, which makes it hard to crack against bending in the top / sole direction, and has a thin periphery to improve repulsion (golf with such a face attached. The club head) can be easily manufactured.

The forging step shown in FIG. 7 may be performed by hot forging or cold forging. In this case, cold forging is more preferable because a thin-walled portion (and a thick-walled portion) is formed without changing the characteristics of the material so much that a face having high durability can be manufactured.

When the head is a wood type, the face is bulged and rolled. Figure 9
Is for the face 10 formed as shown in FIG.
It is sectional drawing which showed the face curved in the toe-heel direction and the top-sole direction by performing a press process further.

By the forging process, the thickness of the thick portion 10a at the center position P1 is about 2.3 mm, and the thickness of the thin portion 10b at the position P2 near the center is about 2.1 mm.
The thickness at the position P3 near the periphery of b is about 1.5 to 1.8 m.
It is processed to have a thickness of m (in the wood type head, it is preferable that there is a thickness difference of about 0.3 to 0.8 mm between the thin portion and the thick portion). In addition, bulge on the face,
The die may be designed in advance so that the pressing step for rolling can be performed simultaneously with the forging step shown in FIGS. 6 and 7. Further, in this case, if a rolled material having a thickness of 2.3 mm, which is the same as the thickness of the thick portion 10a, is used, the amount of plastic deformation of the thin portion can be reduced and the manufacturing becomes easy.

FIG. 10 is a view showing a modified example of the face obtained by the above-mentioned manufacturing process, showing an example in which the thick-walled portion is formed without pressing the center side of the face at all in the above-mentioned forging process. ing. With this configuration,
Since the thick portion 10a is not pressed at all, the thick portion 10a is formed in a flat shape, and the rolling direction (long crystal grain direction) of this portion is not affected by the forging process and is oriented in the top / sole direction. It is in a state.

The face created as described above is
As shown in FIGS. 2 and 3, the head body 5 is fixed to the opening by welding or the like. In this case, the peripheral edge of the face is bent to the back side by a press or the like to project the collar,
This collar may be fixed to the head body by welding or the like.

Although the embodiment of the present invention has been described by taking the wood type golf club head as an example, the present invention can be applied to an iron type head. Of course, also in this case, the rolled metal plate is forged to form a face having a thick portion and a thin portion.

[0036]

As described above, according to the present invention,
It is possible to obtain a golf club head having a metal face of sufficient strength with varying wall thickness, and a method for manufacturing such a golf club head.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of a golf club head according to the present invention.

FIG. 2 is a plan sectional view of the golf club head shown in FIG.

3 is a side sectional view of the golf club head shown in FIG.

FIG. 4 is a front view showing a second embodiment of the golf club head according to the present invention.

FIG. 5 is a view showing the method of manufacturing the golf club head according to the present invention, showing the first step of forming a face.

FIG. 6 is a cross-sectional view showing a second step (forging step) of forming a face.

FIG. 7 is a cross-sectional view showing a step that follows FIG.

FIG. 8 is a perspective view of a face created by the steps of FIGS.

9 is a cross-sectional view showing a state where the face shown in FIG. 8 is further processed.

FIG. 10 is a view showing a modified example of the face.

[Explanation of symbols]

1 golf club head 5 head body 10, 20 faces 10a, 20a thick part 10b, 20b Thin part 30 rolled metal sheet F face material

Claims (7)

[Claims] 1. A golf club head comprising a face having a thick portion and a thin portion formed by forging a rolled metal plate. 2. The golf club head according to claim 1, wherein the face is rolled in the top-sole direction and has a thick central portion. 3. The golf club head according to claim 1, wherein the thin wall portion has crystal grains oriented in the same direction as the thick wall portion. 4. The thin portion has crystal grains oriented in the peripheral direction of the face.
Alternatively, the golf club head according to item 2. 5. When manufacturing a golf club head having a metal face having a thick portion and a thin portion, a rolled metal plate is forged to form a face having a thick portion and a thin portion. A method for manufacturing a golf club head, characterized in that 6. The metal plate constituting the face is rolled in the direction of the top / sole, and thereafter, the pressing amount by the forging is increased from the central side to the peripheral side.
A method for manufacturing a golf club head according to 1. 7. The method of manufacturing a golf club head according to claim 5, wherein the forging is cold forging.