JP2878980B2 - Golf club head - Google Patents

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 of a wood type called a driver or fairway wood, and more particularly to a metal golf club head having a volume of 200 cc or more.

[0002]

2. Description of the Related Art In a conventional metal golf club head, for example, a golf club head formed of a stainless steel material, the thickness of a ball striking surface portion is uniform and formed to a thickness of 2.7 mm or more. None of the parts differed in thickness.

[0003]

When the size of a metal golf club head is increased to 200 cc or more, the head weight increases if the thickness of the ball striking portion is made uniform at 2.7 mm or more. If the thickness of the entire ball striking surface is uniformly reduced, the strength is reduced. The wall thickness remains the same to maintain the strength of the ball striking surface, the center of gravity increases when the thickness of the sole is reduced, and the weight around the head cannot be distributed when the thickness of the head is reduced, reducing the moment of inertia. And the sweet area becomes smaller. With a metal golf club head, the volume is 200
In the case of cc or more, it was difficult to design various characteristics such as head weight, strength, center of gravity position, and moment of inertia to desired values.

[0004] Therefore, the present invention is to increase the size
It is an object of the present invention to provide a golf club head capable of preventing a decrease in strength of a ball striking surface portion, suppressing an increase in head weight, and enabling a desired design.

[0005]

In order to achieve the above-mentioned object, the present invention provides a cast stainless steel having a volume of 200 cc or more.
In the wood-based golf club head made of stainless steel, it is the center part including the sweet area of the ball striking part , and
The center part is meat from the crown part to the sole part.
Thickness, and the toe side and
The wall thickness on the side of the wall is set thinner than the center
The thickness of the toe side and heel side adjacent to the center part,
2.0 to 2.5 mm .

[0006]

According to the present invention, the center portion of the ball striking surface where the ball hits frequently has a sufficient thickness in terms of strength.
On the other hand, the flesh of the portion adjacent to the center portion is shaved to reduce the weight of the entire hitting surface portion. The portion adjacent to the center portion is supported by the sole portion, the crown portion, and the side wall portion, so that it can have a sufficient strength even if formed a little thin, and thus has a sufficient strength as the whole head and strength. And the size of the entire head can be increased.

[0007]

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

In the embodiment shown in FIG. 1, the entire head is formed of a metal such as stainless steel, and the thickness of the center portion 2 including the sweet area of the ball striking portion 1 is the same as that of the portion 3 adjacent to the center portion 2 of the ball striking portion 1. It is formed thicker than the wall thickness. Here, the sweet area means an area in the center where the ball flies most. In a wood club such as a driver, the ball striking surface portion 1 is generally measured from the center of gravity of the club head.
The portion close to the intersection on the ball striking surface 1 when the perpendicular is drawn is called a sweet spot. The flight distance when a ball is hit with this sweet spot is set to 100, and the flight distance even when this sweet spot is removed is 100. In the present invention, 95 or more locations are called sweet areas. In FIG. 1, reference numeral 4 denotes a sole portion, reference numeral 5 denotes a crown portion, and reference numeral 6 denotes a hosel which is a rising portion of a head joined to a shaft.

FIG. 2 shows a front view of the head. In this example, the entire area extending in the vertical direction of the ball striking face portion 1 including the sweet area is defined as a center portion 2, and both sides thereof are defined as adjacent portions 3.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. The center portion 2 is formed to be thicker than the adjacent portion 3. The thickness of the center portion 2 is 2.5 to 3.0 mm in a stainless steel wood, and preferably about 2.7 mm. The thickness of the adjacent portion 3 is 2. 0 to 2.5 mm, preferably 2.1 to 2.5 mm.
It is 2.4mm.

In the embodiment shown in FIGS. 1 to 3, when the whole is made of a stainless steel material, the volume is 210 cc, the thickness of the center portion 2 in the ball striking surface portion 1 is 2.7 mm, and the thickness of the adjacent portion is 2 mm. .4 mm, thickness of crown 5 is 1
mm and the thickness around the head was 1 mm, the head weight was the same as a conventional stainless steel head having a volume of 190 cc and the thickness of each part being 2.7 mm. Although the specific gravity of stainless steel was 7.8, even if the volume was increased to 210 cc, the optimum weight was secured, and the strength of the striking face portion 1 could be sufficiently maintained . Contact name to the thickness of the sole portion 4 and less than 1.5mm, since usually the sole portion 4 welded later to other head portion, together with the welding can not be well with more thinning, reduce the center of gravity You will not be able to do it.
When the thickness of the crown portion 5 is less than 1 mm, there is a problem that when casting is performed, a problem of molten metal flow occurs, and good moldability cannot be obtained. Further, if the area around the head is less than 1 mm, there is a problem in strength . It was but <br/>, it is difficult to thinner than the value mentioned above the thickness of the portion other than the striking surface 1. Therefore, the thickness of the ball striking surface portion 1 is partially reduced to reduce the overall weight.

FIG. 4 shows a second embodiment, in which a rib 7 is formed at the boundary between the center portion 2 of the striking surface portion 1 and the portion 3 adjacent thereto. The rib 7 may partially cover the sole portion 4 as shown in FIG.

In any of the embodiments described above, the hollow portion inside the head may be filled with urethane foam.
The filling sound can be improved by filling the urethane foam. In order to further increase the moment of inertia of the head, it is desirable not to fill the urethane foam. Here, the moment of inertia is a force that, when a moving object receives an action from the outside, attempts to maintain a constant movement against the action. If the moment of inertia is large, when the ball is hit, the head is hard to bend even when the center is removed (the ball cannot be turned greatly due to the impact at the time of hitting the ball), and the flight distance does not decrease much.

In the area of the center portion 2 and the area of the adjacent portion 3, the ratio of the center portion 2 to the entire ball striking surface portion 1 is preferably less than 50%. That is, the adjacent part 3
Is preferably larger than the area of the center portion 2.

[0015]

As described above , according to the present invention,
For example, cast stainless steel wood with a volume of 200cc or more
In the golf club head, the sweet area
A center part including a
Set the thickness from the crown to the sole to make it thicker.
Thickness on the toe side and heel side adjacent to the center of the
Is set thinner than the center part, and
The thickness of the adjacent toe side and heel side is 2.0 to 2.5
Since it is mm, the weight of the hitting surface portion can be reduced, the weight of the entire head can be reduced, and the volume can be increased accordingly. In addition, by reducing the thickness of the peripheral portion, it is possible to design the position of the center of gravity and expand the sweet area, thereby increasing the degree of freedom in design.

[Brief description of the drawings]

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

FIG. 2 is a front view.

FIG. 3 is a sectional view taken along the line AA of FIG. 2;

FIG. 4 is a sectional view similar to FIG. 3, showing an example in which ribs are provided.

FIG. 5 is a partial side sectional view of an example in which ribs are provided.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hitting surface part 2 Center part 3 Adjacent part 7 Rib

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Daisuke Sampei, 20 Onohara, Chichibu City, Saitama Prefecture, inside Bridgestone Sports Co., Ltd. (56) References JP-A-4-25664 (JP, A) Jpn. (JP, U) Actually open 1979-149657 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) A63B 53/04

Claims (2)

(57) [Claims] 1. A wood-based golf club head made of cast stainless steel having a volume of 200 cc or more, a center portion including a sweet area of a ball striking surface portion .
And the center part is sole from the crown part
Thickness at the toe side and the heel side adjacent to the center.
Is set thinner than the center part, and the thickness of the toe side and heel side adjacent to the center part
Is 2.0 to 2.5 mm . 2. The golf club head according to claim 1, wherein a rib is formed at a boundary between the center portion of the ball striking surface portion and the thicknesses of the toe side and the heel side portion adjacent thereto.