JPH0443247Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an iron head for a golf club.

(Prior Art) Conventionally, as shown in FIGS. 6a and 6b, the sole portion 2'
An iron head 1' for a golf club is known in which a metal core 3' provided integrally with a metal core 3' is coated with a fiber-reinforced plastic outer skin 4'. There are also products with increased adhesive strength between the plastic part and the plastic part (for example, Utility Model Application No. 16670/1983).

In all of these conventional iron heads, the metal parts, including the shaft insertion part, sole part, and core, account for approximately 90% of the weight of the entire head (approximately 70% by volume), and the strength that the head should have is , most of which depends on the metal parts mentioned above.

(Problems to be solved by the invention) However, since most of the above conventional heads are made of metal, there is a problem in that the lightweight effect of using fiber-reinforced plastic (FRP) cannot be sufficiently achieved. There is a point. In order to solve this problem, if the metal core was made smaller, the adhesive strength between the fiber-reinforced plastic and the core decreased, causing the problem that the fiber-reinforced plastic layer would peel off when the ball was hit with the club face.

(Means for Solving the Problems) In order to solve the above problems, the present invention employs the following configuration.

That is, the golf club head according to the present invention includes a metal sole portion continuous with the shaft insertion portion, and a metal core body integral with the sole portion and protruding upward, and the core body is made of fiber-reinforced plastic. The head of a golf club is formed by covering an outer skin, and the upper half or more of the height of the head is formed of a fiber-reinforced plastic layer without a metal core, and the core is formed under the core. The sole is provided with a through hole that opens on both the front and back sides of the body, and the through hole is filled with fiber-reinforced plastic that is continuous with the fiber-reinforced plastic that serves as the outer skin.

(Function) Since the metal core can be made smaller, the weight of the head can be reduced. The fiber-reinforced plastic on both the front and back sides are bonded together through the holes provided in the sole, so the adhesive strength to the core is high.

(Embodiment) FIGS. 1 and 2 show an embodiment of the present invention, in which a head 1 has a metal sole portion 2
A metal core 3 integrally provided with the sole portion protrudes upward from the sole portion 2, and a shaft insertion portion 5 is integrally formed at the base of the sole portion 2. A through hole 7 is formed in the sole portion 2 so as to pass under the core body 3 and communicate with both the front and back sides of the core body. As shown in FIG.
Alternatively, a shaped groove may be formed in advance, and the core body 3 may be welded onto the groove. In the illustrated example, the protrusion height h of the core body 3 from the sole portion 2 is suppressed to 12.7 mm or less. Therefore, the volume of the core body 3 is significantly smaller than that of the conventional one. Thus, in accordance with the Japan Golf Association's opinion regarding carbon heads (non-metallic club heads), the protruding height of the core 3 is preferably 12.7 mm or less.

A covering layer of fiber-reinforced plastic 4 is provided on the outer surface of the core body 3. The through hole 7 is filled with fiber-reinforced plastic that is continuous with the covering layer. Reinforcing fibers for fiber-reinforced plastics include carbon fiber, glass fiber, silicon carbide fiber,
Various fibers can be used, such as boron fibers, amorphous metal fibers, and stainless steel fibers. In particular, as the plastic reinforcing fibers filled in the through holes 7, it is preferable to use long fibers than the plastic reinforcing fibers in other parts in terms of strength.

Such a head can be manufactured, for example, as follows. First, the metal part may be formed by integrally molding the sole part 2 connected to the shaft insertion part 5 and the core body 3 protruding upward from the sole part, and then the through hole 7 may be bored. Like,
The sole part 2 connected to the shaft insertion part 5 may be provided with a groove in advance, and then the core body 3 may be placed on the groove and integrated by welding.

In either case, the number of through holes 7 may be one,
There may be more than one. It is better to make the cross-sectional shape of the through hole 7 rounded without edges.
This is preferable for improving the flow of fibers and resin.

The metal part thus obtained is set in a predetermined mold, and fiber-reinforced plastic is integrally molded by compression molding. Before this molding, a bundle of long reinforcing fibers 10 or a ball of fibers knitted in a cross shape may be passed through the through hole 7 in advance as shown in FIGS. 4 and 5. . Or,
A fiber-reinforced plastic block that is slightly smaller than the final shape is formed, and a cross-woven fiber is wrapped around it, and a part of it is passed through the hole 7.
It may be passed through and then compression molded.

The head obtained in this way can have fewer metal parts than conventional ones, so
The weight of the head can be reduced, and the degree of freedom in design increases accordingly. Even if there are fewer metal parts, the plastic parts are still bonded through the holes in the sole, so the adhesive strength is high and peeling is less likely to occur. Therefore, even if the height of the metal core of the non-metallic club head is kept to 12.7 mm or less as described above, sufficient strength can be obtained. Furthermore, since the weight of the head can be reduced while maintaining the conventional head shape, it is possible to increase the speed of the head during swing and increase the flight distance of the ball. On the other hand, if the weight of the head is the same as that of conventional products, the shape can be made larger, so for example, the sole can be made wider to make it easier to swing, and the entire head can be made larger. It can also make it easier to hold the ball. Furthermore, if the weight and shape of the head are the same as those of conventional products, a material with a high specific gravity can be buried in any part. For example, if a weight with a large specific gravity is buried in the toe portion 11 of the head,
Since the center of gravity of the head moves toward the toe side, it is possible for golfers who tend to hit the ball to hit the ball farther. Further, by embedding weights in the toe portion 11 and the heel portion 12, the moment of inertia around the center of gravity of the head increases, and the so-called sweet area is expanded, so that miss shots are reduced.

(Effects of the invention) As is clear from the above explanation, the head of the golf club according to the invention has more than the upper half of the height of the head formed of a fiber-reinforced plastic layer without a metal core. In addition, a through hole is provided in the sole portion that goes under the core body and opens on both the front and back sides of the core body, and the fiber-reinforced plastic that becomes the outer skin is inserted into the through hole. Since it is filled with fiber-reinforced plastic that is continuous with the sole, the base of the fiber-reinforced plastic has a structure that embraces the metal core that is integrated with the sole, resulting in a high bonding strength to the metal part.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of an example of the head for a golf club according to the present invention;
Fig. 2 is a side sectional view of the club head, Fig. 3 is a side sectional view showing a different embodiment, Figs. 4 and 5 are explanatory diagrams of reinforcing fiber arrangement method, and Fig. 6 a and b are explanations of a conventional club head. It is a diagram. 1, 1'...Head, 2, 2'...Sole part,
3, 3'... core body, 4, 4'... outer skin, 5... shank insertion part, 7... through hole.

Claims (1)

[Scope of utility model registration request] A metal sole part that is continuous with the shaft insertion part,
A golf club head comprising a metal core integral with the sole portion and projecting upward, the core being covered with a fiber-reinforced plastic outer skin,
The upper half or more of the height of the head is formed of a fiber-reinforced plastic layer without a metal core, and a through hole is provided in the sole portion so as to go under the core and open on both the front and back sides of the core. A head of a golf club, characterized in that the through hole is filled with fiber-reinforced plastic that is continuous with the fiber-reinforced plastic that serves as the outer skin.