JPH11347160A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a clubface which hardly gives rises to plastic deformation in a clubface member at the time of hitting a ball and is capable of exhibiting high elastic force regardless of the different values of a head speed by forming at least the fitting surface of a face part of a metallic material having prescribed specific yield strength and elastic modulus. SOLUTION: A head body 2 exclusive of the face member 1 is formed of a stainless steel (sp. gr. 7.9) and the sweet area portion 1A of the face member 1 is formed of an aluminum-scandium alloy (sp. gr. 2.9) of 2.5 mm in thickness. The face part 1 is fitted to a peripheral edge 2A of the inner peripheral of the head body 2 and at least the hitting surface thereof is formed of the metallic material having the specific yield strength of >=200 and the elastic modulus (GPa) of <=80. The face member 1 is extremely small in sp. gr. and large in the specific yield strength and is small in the elastic modulus and, therefore, there is no need to make the thickness of the face member 1 extremely small and even if the thickness exceeds 3 mm, the so-called peripheral weight distribution is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club head and, more particularly, to a golf club head having an improved member serving as a hitting surface of a face member of a golf club.

[0002]

2. Description of the Related Art The face portion of a golf club head hitting a ball has conventionally been increased in hardness assuming that the coefficient of restitution on the face surface can be increased.
In recent years, the face surface has been made as thin as possible, and while the elastic deformation at the time of impact has been large, the amount of deformation of the ball has been moderately suppressed, the hysteresis loss of the ball has been reduced, and the energy loss of the ball has been reduced as much as possible. Attempts have been made to increase the flight distance of the vehicle (Japanese Patent Laid-Open No. 8-16).
No. 8541).

[0003]

However, by simply increasing the hardness of the face surface, there are few materials having hardness and workability higher than those of titanium alloys, and there is a limit to the increase in the flight distance, and the face surface is hardly improved. Increasing the elastic deformation by making it extremely thin may cause unnecessary vibrations on the face surface at the time of hitting, thereby changing the feeling of hitting and the directionality of the hit ball, and may violate the rules of the golf rules. On the other hand, when the high-strength material described in the above-mentioned publication is used, the flexural rigidity (or elastic modulus) of the face surface becomes too large, and when a general player hits, the elasticity of the face surface material is reduced and a large impact force is applied. This causes a problem that the deformation of the ball is increased, the hysteresis loss increases, the energy loss of the ball increases, and the increase in the flight distance is suppressed.

Accordingly, in view of the above circumstances, it is an object of the present invention to provide a face surface material that is unlikely to undergo plastic deformation when hit with a ball, and that has high elasticity regardless of the magnitude of the head speed. An object of the present invention is to provide a golf club head having a face surface that can be used.

[0005]

According to the present invention, there is provided a golf club head having a metal hollow shell, wherein at least a striking surface of a face portion has a specific yield strength of 200 or more and an elastic modulus. (GPa) is formed of a metal material of 80 or less. Further, this metal material is preferably an aluminum alloy having a Pickers hardness of 200 or more, and particularly preferably an aluminum-scandium alloy. The composition of the aluminum-scandium alloy is such that about 0.02 to about 10.0% by weight of scandium and about 0.10 to about 1.0% by weight of zirconium are contained with aluminum as a main component.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows one embodiment of the present invention.
FIG. 3 is a cross-sectional view of the center of a face of a number iron.

The head body 2 excluding the face member 1 is made of stainless steel (specific gravity 7.9), and an aluminum-scandium alloy (specific gravity 2.9) in which the thickness of the sweet area 1A of the face member 1 is 2.5 mm. It has been. Here, the composition of the aluminum-scandium alloy in this example is such that 0.1% by weight of scandium and 0.11% by weight of zirconium are contained in a 7000 series aluminum alloy. The face member 1 has the face member 1 fitted to the inner peripheral edge 2A of the head main body 2 in accordance with the structure of a normal cavity iron. Symbol 3 in the figure
Denotes a cavity, and reference numeral 4 denotes a hosel. Since the specific gravity of the face member 1 is extremely small, as shown in Table 1 below, the specific yield strength is extremely large and the elastic modulus is small, so that the thickness of the face member 1 does not need to be extremely thin. Is greater than 3 mm, so-called peripheral weight distribution (which increases the moment of inertia of the head to improve the directionality of the hit ball) is possible, and also prevents the plastic deformation due to the high head speed and the elasticity of the face member 1. Improvement can be easily performed. In addition, although it is a kind of aluminum alloy, it has a high Vickers hardness (about three times that of ordinary cast aluminum), is excellent in hitting feeling, further increases the flight distance, and is less likely to damage the face surface 1B.

[0009] In the above embodiment, the number of irons is five, but the present invention is not limited to other iron clubs, but may be a wood club or a utility club (a club having characteristics between wood and iron). ) Can also be applied to the head.

[0010]

[Table 1]

[0011]

As described above, according to the present invention,
In the head made of a metal hollow shell, at least the striking surface of the face portion has a specific yield strength [yield strength (MPa).
Divided by the density (g / cm ³ )] and a metal material having an elastic modulus (GPa) of 80 or less. As a result, when a player with a large head strength with a high head speed hits, a so-called elastic area of the face face material is wide, so that plastic deformation (or permanent deformation) hardly occurs, and a player with a low head speed hits. In this case, much of the impact force at the time of impact is absorbed as internal loss of the face surface material, and the deformation of the ball is suppressed because the elastic modulus is considerably lower than the material of the conventional product (titanium, maraging steel, etc.) The energy loss of the ball can be reduced and the flight distance can be increased. Therefore, it is possible to provide a golf club head that flies well over a wide range of head speeds, that is, for a wide range of players from seniors to average golfers.

Further, the metal material has a Vickers hardness of 2
In the case of an aluminum alloy of 00 or more, in addition to the above-described functions and effects, the hardness of the face surface is 1.3 to 3 times higher than that of a normal aluminum alloy, and the hardness is comparable to that of an iron material. A better hit feeling can be obtained as the flight distance further increases. At the same time, the weight of the face member is reduced, so that the size of the head can be easily increased. In particular, aluminum-
In the case of using a scandium alloy, the yield strength becomes extremely high without increasing the weight of the head, and the Vickers hardness also becomes large. The plastic ball is not plastically deformed, and the large elasticity of the material reduces the energy loss of the hit ball, thereby increasing the flight distance. Moreover, in this case, since the head weight can be reduced, the club can be made longer to further increase the head speed,
It is easy to further increase the flight distance.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a preferred embodiment of the present invention.

[Explanation of symbols]

 1 face member 1A sweet area 1B face surface

Claims (3)

[Claims] 1. A golf club head having a hollow metal shell, wherein at least a striking surface of a face portion is formed of a metal material having a specific yield strength of 200 or more and an elastic coefficient (GPa) of 80 or less. Golf club head characterized by the following. 2. The golf club head according to claim 1, wherein the metal material is an aluminum alloy having a Vickers hardness of 200 or more. 3. The method according to claim 1, wherein the metal material is an aluminum-scandium alloy.
A golf club head according to claim 1.