JPH11104283A - Club head for golf - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a sweet area wider and centroid lower. SOLUTION: This club head is constituted by forming a recessed part 4 on the back face 2b side corresponding to the club face 2a in the ball hitting part 2 of a head 1 consisting of a metallic preform molded by a powder metal injection molding means. The sole face 2c side thereof is formed to a thick and broad bulging part 5 and the inner peripheral part 4a on the club-face 2a side of the recessed part 4 on the back face side is provided with a slit 6.

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 such as an iron club or a putter club, and more particularly to a golf club head having a wider hitting portion formed on a back surface side of a hitting portion of a head and an expanding sweet area. , Lowering the center of gravity.

[0002]

2. Description of the Related Art Conventionally, in a golf club of this kind, for example, an iron club, a head is formed by casting or forging, a center of gravity is lowered, a sweet area is expanded by adjusting a depth of a center of gravity, and a peripheral weight is increased. As shown in FIG. 4, a concave portion d is formed on the side of the back surface c corresponding to the face surface b of the head hitting portion a to improve the hitting characteristics such as an increase in the moment of inertia due to the distribution. Some have a cavity-type structure in which the e side is formed as a thick and wide bulged portion f.

[0003]

However, in the head having such a conventional structure, in order to promote a lower center of gravity, the thickness T of the swelling portion f on the sole surface e side of the head hitting portion a is required. However, the width W of the concave portion d is reduced, and the sweet area cannot be enlarged by widening the concave portion d, so that a soft shot feeling cannot be obtained.

Therefore, as shown in FIG. 5, in order to increase the width W of the concave portion d in the head hitting portion a to enlarge the sweet area, the thickness T on the sole surface e side must be changed to the thickness of the die. Although it is conceivable to reduce the thickness as much as the punching taper allows, reducing the thickness dimension T on the sole surface e side itself is
Not only is there a limit due to the taper of the die, but also the height of the center of gravity increases, so that the center of gravity cannot be lowered.

An object of the present invention is to provide a golf club head capable of reducing the center of gravity as well as expanding the sweet area.

[0006]

In order to solve the above-mentioned problems, the present invention is directed to a back surface side corresponding to a face surface of a hitting portion of a head made of a metal base material formed by powder metal injection molding means. A golf club head having a sole surface side formed as a thick and wide bulged portion, and a slit formed in a face surface side inner peripheral portion of the back surface side concave portion of the hitting portion. In this case, an elastic body is filled in the slit, or the sole surface side swelling part is a weight body having a higher specific gravity than the metal base material of the hitting part. It is formed by forming.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings shown in FIGS. 1 to 3. As shown in FIG. 1, reference numeral 1 denotes a head.

In this head 1, a ball hitting portion 2 and a hosel portion 3 are integrally formed by a powder metal injection molding means described later from a metal base material such as titanium or a titanium alloy, and as shown in FIG. In addition, there is a cavity type structure in which a concave portion 4 is formed on the side of the back surface 2b corresponding to the face surface 2a of the hitting portion 2.

The sole surface 2 of the head hitting portion 2
The c-side is formed in a thick and wide bulged portion 5, and a slit 6 is formed in the face surface 2 a side of the inner peripheral portion 4 a of the recess 4 on the back surface 2 b side corresponding to the bulged portion 5. The inside of the slit 6 is filled with an elastic body 7 such as rubber.

The head 1 is manufactured by a powder metal injection molding method. The powder metal injection molding method is, for example, a method in which a fine metal powder raw material having a size of 1 to 600 μm, preferably about 5 to 100 μm is mixed with wax, A binder such as a resin is added and the compound of the kneaded metamold is granulated by a granulator and pelletized, and the pelletized head molding material is supplied to an injection molding machine and fluidized to a desired level. A head green body is formed by injecting and filling into a cavity of a molding die having an outer shape of the head, a heat treatment is performed on the head green body to remove a binder, and the head green body after the removal of the binder is sintered. The inside of the head 1 after molding exhibits a porous structure containing microbubbles.

With this, the degree of freedom of the head shape at the time of molding is increased, and the head material density can be easily controlled.
The setting can be adjusted in the range of% to less than 100%.

That is, in order to manufacture the head 1 having the above structure, as shown in FIG. 3, a titanium or titanium alloy powder raw material is placed in a cavity 11 of a molding die 10 having a predetermined head outer shape. Head molding material 2
The head green body 20 is injection-molded by filling 1 with two-color molding or the like.

Next, the head green body 20 is subjected to heat treatment, and after sintering after binder removal, a completed product of the head 1 as shown in FIGS. 1 and 2 is obtained.

As described above, by molding the head 1 by powder metal injection molding means, it is possible to increase the thickness dimension T of the bulging portion 5 formed on the sole surface 2c side of the head hitting portion 2. Therefore, the center of gravity can be reduced by increasing the thickness of the bulging portion 5, and at the same time, the slit 6 formed by cutting the inner peripheral portion 4 a of the concave portion 4 on the back surface 2 b side into the face surface 2 a side can form the concave portion 4. Since the width W can be increased, the sweet area can be enlarged.

In the above-described embodiment, the slit 6 cut into the concave portion 4 on the back surface 2b side of the hitting portion 2 of the head 1 is formed only at a portion corresponding to the bulging portion 5 on the sole surface 2c side. However, it is also possible to form it on the upper side of the head, the toe side and the heel side, and the cut depth is also uniform, or the depth becomes gradually shallower, for example, from the head center to the toe side and the heel side. It may be formed in such a size distribution, and is adjusted to an appropriate form according to the hitting characteristics such as the moment of inertia due to the peripheral weight distribution.

The bulging portion 5 formed on the sole surface 2c side of the head 1 is made to have a specific gravity higher than that of the metal base material forming the hitting portion 2 by, for example, two-color molding using powder metal injection molding means. May be formed of a weight body made of a molding material containing a dissimilar metal such as a tungsten alloy, thereby making it possible to promote lowering of the center of gravity.

Furthermore, although an iron club has been described as an example of a golf club head, the present invention can also be applied to a putter club and the like.

[0018]

As is apparent from the above description, according to the present invention, a recess is formed on the back surface side corresponding to the face surface in the hitting portion of the head made of a metal base material formed by powder metal injection molding means. Since the sole surface side is formed as a thick and wide bulging portion and a slit is provided in the face surface side inner peripheral portion of the back surface side concave portion, the width dimension of the concave portion can be increased. In addition, since the thickness of the bulging portion formed to bulge on the sole surface side of the head hitting portion can be made thick, the sweet area can be enlarged and the center of gravity can be lowered.

Further, by filling an elastic body such as rubber into the slit formed by cutting the concave portion on the back surface side of the head, it is possible to prevent foreign substances such as dust and dirt from entering the slit.

Further, by forming the bulging portion formed on the sole surface side of the head with a weight having a higher specific gravity than the metal base material forming the hitting ball portion, it is possible to promote a lowering of the center of gravity.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of an iron club head as a golf club head according to the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is an explanatory view showing a molding state of a head green body by the same powder metal injection molding means.

FIG. 4 is a sectional view showing a conventional iron club head.

FIG. 5 is a sectional view showing another example of the conventional iron club head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Head, 2 ... Hitting part, 2a ... Face surface, 2b ... Back surface, 2c ... Sole surface, 4 ... Depression, 4a ... Inner peripheral part, 5 ... ··· Swelling part, 6 ··· slit, 7 ··· elastic body, T · · · thickness of the bulging part, W · width of the recess.

Claims (3)

[Claims] 1. A concave portion is formed on a back surface side corresponding to a face surface of a hitting portion of a head made of a metal base material formed by a powder metal injection molding means, and a sole surface side of the head surface is made thick and wide. A golf club head formed in a bulging portion, wherein a slit is provided in an inner peripheral portion of a face side of a back surface side concave portion of the hitting portion. 2. The golf club head according to claim 1, wherein an elastic body is filled in the slit. 3. The golf club head according to claim 1, wherein the bulge portion on the sole surface side of the hitting portion is formed of a weight having a higher specific gravity than the metal base material of the hitting portion.