JP2001212271A - Iron head for golf club, its manufacturing method and iron golf club using thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an iron golf club head which has a large moment of inertia, a low center of gravity and much freedom in designing. SOLUTION: In an iron golf club head, an impact face is composed of a particle enhanced composite material with an aluminum alloy containing at least one element selected from the group consisting of beryllium, magnesium, silica, nickel, copper, zinc and manganese and at least one element selected from the group consisting of beryllium, magnesium, silica, nickel, copper, zinc and manganese and one element selected from the group consisting of chromium, iron, titan and zirconium. Further, the body part is composed of at least one element selected from the group consisting of titanium alloys, soft iron, iron alloys, nickel alloys and copper alloys.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron club head for a golf club having at least a striking surface portion, a body portion and a shaft fitting portion and formed into an iron club head shape, a method of manufacturing the same, and a golf using the head. About the Iron Club.

[0002]

2. Description of the Related Art In the past, soft iron was mainly used as an iron-shaped golf club head. However, in recent years, titanium alloys, stainless steels, maraging steels, and the like having higher strength have been used. To reduce the wall thickness of the ball striking surface and distribute the weight around the body,
The sweet spot is enlarged or distributed to the bottom to reduce the center of gravity. Recently, a titanium alloy having a small specific gravity has been used for a ball striking surface portion, and a stainless steel having a large specific gravity has been used for a body portion, thereby increasing the moment of inertia and changing the material of the face portion. The weight loss due to this is also increased by increasing the weight of the sole portion of the body portion, thereby lowering the center of gravity.

[0003]

SUMMARY OF THE INVENTION

In the latest head described above, the specific gravity of the titanium alloy used for the ball striking face portion and the specific gravity of the stainless steel used for the body portion are 4.43 and 7.8, respectively.
7, the difference in specific gravity increases the inertia moment of the head by distributing a large amount of weight at the center of the head to the periphery of the head. As a result, although a certain degree of effect is obtained, the difference in specific gravity between the two metals is 1.78, which does not sufficiently increase the moment of inertia and lower the center of gravity.

Therefore, there has been a strong demand for an iron club head having a lower center of gravity with a larger inertia moment of the iron club head itself.

The present invention has been made to improve the above-mentioned drawbacks of the conventional iron club head and the prior-art wood club head.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art. The present inventor has conducted a study to improve the moment of inertia of the iron-shaped golf club head and to obtain a club head having a large hitting surface sweet spot and a low center of gravity. went. As a result, they have found that beryllium having a much lower specific gravity is used instead of conventional titanium alloy, stainless steel, maraging steel, and the like.

[0008] The specific gravity of beryllium is very low at 1.85. 1.48th of aluminum (2.699) and 2.14 of titanium (4.43) conventionally used for golf club heads.
It is a very light metal with a 1 / 47th ratio and 4.32 times smaller than iron (7.87). Nevertheless, the high modulus, especially the specific modulus, is surprising, about 6.3 times that of aluminum, titanium and iron. Also, the specific strength is high, and if titanium (6Al-4V) is 1, the aluminum alloy (7075-T
6) is 0.92 and alloy steel (4340) is 0.75, while beryllium is 1.23. Also, the specific fatigue strength is remarkably superior to these materials, and when notched, when compared with the time strength of 10 to the fourth power, beryllium is twice as much as aluminum, 1.45 times as much as titanium, and alloy steel. 2.63 times that of Based on such knowledge, the present invention has been completed. According to the present invention, a metal golf club head having a much larger inertial moment than conventional products and a superior degree of freedom in designing a center of gravity is provided. Can be manufactured.

Further, the beryllium used in the present invention
The aluminum alloy particle reinforced composite material will be described.
The beryllium-aluminum alloy particle reinforced composite material used in the present invention is obtained by mixing fine powder of beryllium and fine powder of an aluminum alloy and subjecting the mixture to hot isostatic pressing or hot extrusion. And manufacture. In contrast, what is usually called an alloy is produced by melting raw materials, casting this, and, if necessary, hot working.
The manufacturing process mainly used in the present invention is thus completely different. By adopting the manufacturing method used in the present invention, a material having extremely excellent mechanical properties and other performances, which cannot be obtained by an alloy manufactured by the manufacturing method, can be obtained. The microstructure of the beryllium-aluminum alloy particle reinforced composite material used in the present invention is one in which fine particles of beryllium are finely dispersed in a matrix of an aluminum alloy. Since it is a composite material having such a structure, it is unlikely to be deformed even when subjected to external stress, that is, it has high strength, high toughness, and high elastic modulus. Further, the aluminum alloy of the matrix can be heat-treated depending on the composition. Accordingly, for example, when an aluminum alloy of 5.6% of zinc, 2.5% of magnesium, 1.6% of copper, 0.25% of chromium, and remaining aluminum is used and subjected to T6 heat treatment, the specific gravity is 2.38 and the tensile strength is increased. Strength 54kgf / square m
m, specific strength 22.7, elastic modulus 12654 kgf / square m
Very excellent mechanical properties such as m and specific elastic modulus 5317 can be obtained.

Still referring to the present invention, the body portion is made of an iron-based alloy such as a titanium alloy, a soft iron, a stainless steel, a maraging steel, a nickel alloy or a copper alloy; A structure is obtained by combining a ball striking surface portion made of a beryllium-aluminum alloy particle reinforced composite material having a much lower specific gravity than that of. Then, the inertia moment of the club head increases due to the difference in specific gravity between the two materials. Thus, the sweet spot is enlarged.

Further, as described in the preceding section,
The weight of the club head is changed by changing from an iron-based alloy such as titanium alloy, soft iron, stainless steel, maraging steel or the like, a nickel alloy or a copper alloy having a higher specific gravity to a beryllium-aluminum particle reinforced composite material having a lower specific gravity. Decrease. Thus, this weight can be placed at any position on the club head. For example, if a material having a very large specific gravity, such as tungsten or a tungsten alloy, is attached to the bottom of the body, the center of gravity becomes low. In this method, a concave portion is provided at the bottom of the body portion, and a material having a very large specific gravity, such as tungsten or a tungsten alloy, is mounted on the concave portion. It is also possible to make the entire bottom portion of the body portion from a material having a very large specific gravity, such as tungsten or a tungsten alloy. By using beryllium for the striking surface, the degree of freedom in designing the club head is greatly improved.

Beryllium has a very high specific modulus as described above. Because of this, the shot feeling is good, and soft iron,
As compared with the case where the ball striking portion is made of an iron-based alloy such as stainless steel or maraging steel, a nickel alloy, or a titanium alloy, there is an effect that the repulsive force at the time of striking is higher and the flight distance is longer.

Beryllium is an expensive material. Therefore,
The inventor has further studied the manufacturing method in order to reduce the manufacturing cost. As a result, beryllium and an aluminum alloy are mixed in a powder state, compression-molded in a cold state, and then sintered and / or hot extruded and / or hot isostatically pressed (Hot Isostatic Pr).
essing), but it has been found possible. This has made it possible to provide the product of the present invention industrially at low cost.

In the case where the ball striking face is made of a particle-reinforced composite material of beryllium and an aluminum alloy, it has been successfully manufactured by the investment casting method. The production of castings from the molten metal or alloy by the investment casting method has already been performed for some metals. However, beryllium and beryllium alloys have poor performance when manufactured by a melting method. However, the inventors have found that by including nickel that particularly improves the flowability in the molten state, the investment casting method using the mixed state of the aluminum alloy in the molten state and beryllium in the solid phase allows the alloy to be beryllium. It has been found that a casting of a particle-reinforced composite material with an aluminum alloy can be manufactured. According to this method, the ball striking surface portion of the golf club head can be provided industrially at low cost.

In the case where the ball striking portion is made of a particle-reinforced composite material of beryllium and an aluminum alloy, the inventors have further studied to reduce the manufacturing cost. As a result, while containing at least one selected from the group consisting of magnesium, silicon, nickel, copper, zinc, and manganese, at least one selected from the group consisting of chromium, iron, titanium, and zirconium Using a semi-molten aluminum alloy containing helium and a solid phase beryllium and solidifying it under pressure to the product shape or a shape close to it, and found that a casting of particle-reinforced composite material can be manufactured. Was. According to this method, it is possible to industrially and inexpensively provide a highly accurate and lightweight ball striking surface portion of a golf club head.

The composition of the material used in the present invention will be described. Beryllium is a pure metal. As impurities
Less than 3% BeO, less than 0.3% Al, less than 0.5% C, less than 0.2% C, less than 0.2% ppm Fe,
It can contain 0.2% or less of Mg and 0.2% or less of Si. The aluminum alloy contains at least one selected from the group consisting of aluminum and magnesium, silicon, nickel, copper, zinc, and manganese, and at least one selected from chromium, iron, titanium, and zirconium. If the content of magnesium is 1% or less, a remarkable improvement in strength cannot be expected, and if it is 10% or more, the ductility sharply decreases. Therefore, the content of magnesium is set to 1% or more and 10% or less. If the content of silicon is 0.3% or less, a remarkable improvement in strength cannot be expected, and if it is 10.0% or more, the ductility sharply decreases.
% Or less. If the content of nickel is 0.1% or less, remarkable improvement in fluidity in the molten state cannot be expected, and 10.0%
Above, the degree of improvement of the effect decreases,
1% or more and 10.0% or less. If the content of copper is 0.1% or less, remarkable improvement in mechanical properties by heat treatment cannot be expected, and if it is 10.0% or more, the degree of improvement in its effect is reduced. It was as follows. If the content of zinc is 0.01% or less, remarkable improvement in mechanical properties by heat treatment cannot be expected, and if it is 10.0% or more, stress corrosion cracking is likely to occur.
It was as follows. When manganese is 0.1% or less, remarkable improvement in strength cannot be expected, and when manganese is 2.0% or more, the ductility rapidly decreases. Therefore, chromium and zirconium are used in an amount of 0.1% or more and 2.0% or less. Means that recrystallized grains are refined and stress corrosion cracking resistance is prevented, but significant improvement cannot be expected in both chromium and zirconium at 0.01% or less, and the improvement of the effect decreases at 5.0% or more. Therefore, the content is set to 0.01% or more and 5.0% or less. Iron improves the strength, but if it is 0.01% or less, no remarkable improvement can be expected. If it is 5.0% or more, the degree of improvement in its effect is reduced. Therefore, iron is 0.01% or more and 5.0% or less. And Titanium improves the corrosion resistance, but if it is 0.01% or less, no remarkable improvement can be expected. If it is 5.0% or more, the degree of improvement in its effect is reduced, so that 0.01% or more and 5.0% or less.
It was as follows.

Further, since beryllium is an expensive material, it is better to reduce the thickness of the ball striking surface as much as possible.
However, the strength decreases when the plate thickness is reduced. Therefore, the striking surface can be made up of a multilayer structure to supplement the strength. That is, the ball striking face portion contains: a) beryllium and at least one selected from the group consisting of magnesium, silicon, nickel, copper, zinc, and manganese, and further comprises chromium, iron, titanium, zirconium, and boron. Another material is bonded to the surface of the particle-reinforced composite material with an aluminum alloy containing at least one selected from the group. The shape is not limited to a plate shape, but may be a three-dimensional structure such as a honeycomb structure. Other materials can be selected from at least one of: b) titanium and titanium alloys, aluminum and aluminum alloys, magnesium and magnesium alloys. In this case, the material selected is not limited to one type but may be two or more types. Also, when the ball striking surface is made of a plurality of materials,
The surface portion of the club that directly receives a hit ball is the above (a),
Any of (b) may be used.

Since the surface of the ball striking surface is often subjected to groove processing, it is sometimes necessary to take measures to improve the notch toughness of the ball striking surface. For this purpose, a multi-layer structure with other materials may be used as described above, but it is selected from the group consisting of iron and iron alloys, nickel and nickel alloys, chromium and chromium alloys, and copper and copper alloys. At least one
The surface may be coated with a seed. As a method of coating, a method such as plating or vapor deposition may be used.

The environment in which the head of a golf club is used is apt to be humid, and is subjected to repeated stress.
Therefore, electrolytic corrosion is likely to occur on the ball striking surface,
Measures are needed to prevent this. Coating the surface is one of the methods. The coating method can be selected from a vapor deposition treatment, a chemical conversion treatment, a ceramic dispersion plating treatment, a CVD coating treatment, a PVD coating treatment, an HCD ion plating treatment, a DLC treatment and a diamond coating treatment.

The basic feature of the present invention is that, as described above, the ball striking surface portion is made of a particle-reinforced composite material of beryllium and an aluminum alloy, whereby excellent properties can be obtained. In some cases, however, these may need to be sacrificed to some extent to reduce costs. In that case, instead of the above-described method based on the powder metallurgy method, it is possible to employ a melting method which is a method of manufacturing an ordinary alloy. A) beryllium b) aluminum c) at least one component of a, b and c selected from the group consisting of magnesium, silicon, nickel, copper, zinc, manganese, chromium, iron, titanium and zirconium. The material contained is uniformly melted by a melting method, then solidified, and plastically worked to form a predetermined shape for use. This makes it possible to supply an iron club head at low cost. .

The above description of the present invention is common to so-called back cavity type irons and hollow type irons.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. It is needless to say that the present invention is not limited to the illustrated one.

First, a golf iron club shown in FIG. 1 according to a first embodiment of the present invention will be described. As shown in FIG. 1, the iron club 1 includes an iron club head 3 and a shaft 5 having a distal end portion 5a fixed to a hosel portion 4d of the head 3 in a fitted state. The head 3 is composed of a body part 4 made of 430 stainless steel, a face part 7 made of a beryllium-7075 aluminum alloy particle reinforced composite material, a sole weight part made of copper-tungsten, and a hosel part 4d. The members are connected to each other. Further, the shaft may be one conventionally used. In the body part,
A window 4 is formed so as to fit the ball striking surface, and the ball striking surface 1 is fixed to the window 4 by press fitting. The surface on the hitting surface side of the body portion and the hitting surface portion are configured to be flat.

FIG. 2 shows a second embodiment of the present invention. When it is desired to reduce the plate thickness of the ball striking surface portion 7, a structure is adopted in which the window 4d at the center of the body portion 4 is closed with a thin wall of another material, and the striking force applied to the ball striking surface portion 7 at the time of ball striking is shared by this portion. hand,
A decrease in strength due to a decrease in the thickness of the ball striking face 7 can be compensated.

FIG. 3 shows a third embodiment of the present invention. In this case, the striking surface has a multiplex structure. That is, the surface of the ball striking surface portion is a beryllium-7075 aluminum alloy particle reinforced composite material, and the back surface is a titanium alloy (Ti-6Al).
-4V). By doing so, the amount of expensive beryllium used can be saved.

[0026]

According to the present invention, in an iron golf clap head, a ball striking surface portion includes beryllium, magnesium,
Group consisting of silicon, nickel, copper, zinc and manganese
And at least one selected from the group consisting of chromium, iron, titanium, zirconium, and boron, and an aluminum alloy containing at least one selected from the group consisting of boron. Is what it is. This particle-reinforced composite material has a lower specific gravity, a higher specific elastic modulus, and a higher specific strength than conventionally used iron-based alloys such as soft iron, stainless steel, and maraging steel, or titanium alloys. Excellent material with high specific fatigue strength. For this reason, according to the present invention, compared with the conventional one, it is light, has a low center of gravity, and has a large repulsive force when hitting a ball,
A golf club head having a large moment of inertia and a large degree of freedom in design can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of a golf iron club according to a first embodiment of the present invention, showing only a tip portion of a shaft.

FIG. 2 is a sectional view of a golf iron club head according to a second embodiment of the present invention;

FIG. 3 is a sectional view of a ball striking surface portion of a golf iron club head according to a third embodiment of the present invention.

[Explanation of symbols]

 1 Golf iron club 3 Iron club head 4 Body part 4 a Body part hosel part 4 b Body part window part Reference numeral 4c: Cover plate portion of the window portion of the body portion 4d: Sole portion of the body portion 5: Shaft 5a: Fitting portion of the shaft 7: Ball striking portion 7a ... Surface portion of the ball striking surface portion having a multilayer structure 7b.

Claims (11)

[Claims] 1. A golf iron club head having at least a ball striking surface portion provided on a front surface, a body portion supporting the same, and a shaft fitting portion for attaching a shaft, and formed in an iron club head shape. , The ball striking surface is beryllium, magnesium, silicon,
Contains at least one selected from the group consisting of nickel, copper, zinc, and manganese;
A golf iron club head comprising a particle-reinforced composite material with an aluminum alloy containing at least one selected from the group consisting of iron, titanium and zirconium. 2. A golf iron club head having at least a ball striking surface portion provided on a front surface, a body portion supporting the same, and a shaft fitting portion for attaching a shaft, and having an iron club head shape. The ball striking portion contains beryllium and at least one selected from the group consisting of magnesium, silicon, nickel, copper, zinc and manganese, and is selected from the group consisting of chromium, iron, titanium and zirconium. Composite material having a multilayer structure of a particle-reinforced composite material with an aluminum alloy containing at least one selected from the group consisting of at least one selected from the group consisting of titanium and titanium alloys, aluminum and aluminum alloys, and magnesium and magnesium alloys A golf iron club, comprising: For the head. 3. The surface according to claim 1, wherein the ball striking surface is made of at least one selected from the group consisting of iron and iron alloys, nickel and nickel alloys, chromium and chromium alloys, and copper and copper alloys. A golf iron club head comprising: 4. The method according to claim 1, wherein the striking surface portion is formed by vapor deposition, chemical conversion coating, ceramic dispersion coating, and CV.
D coating processing, PVD coating processing, HCD
A golf iron club head having a surface coated with at least one selected from the group consisting of an ion plating treatment, a DLC treatment, and a diamond coating treatment. 5. A golf iron club head according to claim 1, wherein at least one member selected from the group consisting of tungsten and a tungsten alloy is attached to a lower portion of the body portion. 6. A golf iron club head according to claim 1, wherein said lower portion of said body is made of at least one selected from the group consisting of tungsten and a tungsten alloy. 7. The method according to claim 1, wherein the striking surface portion is formed by cold-pressing the raw material in a mixed powder state, and thereafter sintering and / or hot extrusion and / or hot-pressing. Pressure (Hot Isostatic Press)
ing) to produce a golf iron club head. 8. The method according to claim 1, wherein the hitting surface portion is made of aluminum, magnesium, silicon, nickel,
It contains at least one selected from the group consisting of copper, zinc, and manganese, and has chromium, iron, titanium,
It is produced by casting by an investment casting method from a coexistence state of a molten aluminum alloy containing at least one selected from a group consisting of zirconium and beryllium in a solid phase. A method of manufacturing a head for a golf iron club. 9. The method according to claim 1, wherein the hitting surface portion is made of aluminum, magnesium, silicon, nickel,
It contains at least one selected from the group consisting of copper, zinc, and manganese, and has chromium, iron, titanium,
It is characterized by being manufactured by solidifying under a pressurized state from a coexistence state of a molten aluminum alloy containing at least one selected from a group consisting of zirconium and beryllium in a solid phase. A method of manufacturing a head for a golf iron club. 10. A golf iron club head having at least a ball striking surface portion provided on a front surface, a body portion for supporting the same, and a shaft fitting portion for attaching a shaft, and having an iron club head shape. The ball striking surface portion is a) beryllium, b) aluminum,
And c) an alloy containing at least one selected from the group consisting of magnesium, silicon, nickel, copper, zinc, manganese, chromium, iron, titanium, zirconium, and boron. A golf iron club head comprising: 11. A golf iron club head comprising a shaft to which the head of any one of claims 1 to 10 is fixed.