JP2002301174A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club head which allows a player to easily take up the stance for hitting a golf ball. SOLUTION: In the plan view in a reference state wherein a golf club head 1 is placed on the horizontal surface at a regular lie angle and a regular loft angle, a boundary line La between a face part 2 and a crown part 3 forming the upper surface of the head is composed of a curved line having a radius of curvature Ra of 280-650 mm, while the crown part 3 has a ridge line Lb extending substantially in parallel with the line La. The interval Wa between the line La and the line Lb in the front and rear directions of the head is 25-35% of the width W of the head being the length from the line La to the rearmost end E of the head in the front and rear directions.

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 which is easy to hold on a target.

[0002]

2. Description of the Related Art In a conventional wood-type golf club head, as shown in FIG. 10, a horizontal curved surface (a so-called "face round") of a face portion a for hitting a ball is used. ") Is traditionally 2
Generally, the radius of curvature R is set to 54 mm (10 inches). Therefore, the boundary line c between the face portion a and the crown portion b forming the upper surface of the head is also set as an arc-shaped curve having a radius of curvature of approximately 254 mm.

However, the golfer usually adjusts the head so that the boundary c is perpendicular to the target direction d, so that the boundary c has a relatively small radius of curvature as described above. If it is curved, there is a problem that it is difficult to align the face portion a in the target direction and it is difficult to hold the face portion a.

Conventionally, in order to accurately align the face portion with a target direction, for example, as shown in FIG. 9A, a triangular mark is colored on the crown portion, and furthermore, Japanese Patent Application Laid-Open No. 3-114477. It has been proposed to form an uneven portion extending along the upper edge of the face portion near the face of the crown portion, but no substantial improvement has been made with respect to the shape of the boundary line or the like. However, there is a limit to improvement in ease of setting, and there is room for further improvement.

The present invention has been devised in view of the above-mentioned problems, and a boundary line between a face portion and a crown portion forming the upper surface of a head is constituted by a curve having a radius of curvature of 280 to 650 mm. A ridge line extending substantially in parallel with the boundary line is provided on the portion, and the boundary line Wa in the front-rear direction between the boundary line and the ridge line is basically limited to a certain range. It is an object of the present invention to provide a golf club head capable of improving the golf club head.

[0006]

According to a first aspect of the present invention, a golf club head is mounted on a horizontal plane at a prescribed lie angle and loft angle in a plane view in a reference state and a top surface of the head section. Is formed of a curve having a radius of curvature of 280 to 650 mm, and has a ridge line extending substantially parallel to the boundary line in the crown portion, and a boundary line between the boundary line and the ridge line. The distance Wa in the front-rear direction is 25 to 35% of the head width W, which is the length in the front-rear direction from the boundary line to the end point of the head.

According to a second aspect of the present invention, the crown portion includes a crown front portion formed between the boundary line and the ridge line, and a small-length sub-portion whose outer surface is recessed behind the crown front portion. 2. The golf club head according to claim 1, further comprising a portion, and a rear portion of the crown smoothly connected to the sub-portion and having a convex outer surface.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a golf club head (hereinafter, sometimes simply referred to as “head”) in a reference state where the golf club head is placed on a horizontal plane at a prescribed lie angle α and loft angle β, and FIG. 3 is a sectional view taken along line AA of FIG. The loft angle α is an angle of the face surface F with respect to a vertical line as shown in FIG. 3, and the lie angle β
Is the angle between the axis center line CL of the shaft insertion portion 6 into which the shaft is inserted as shown in FIG. 2 and the horizontal plane. Note that these angles are set for each head.

In FIG. 1, a head 1 has a face portion 2 having a face surface F for hitting a ball, a crown portion 3 forming an upper surface of the head, a sole portion 4 forming a bottom surface of the head, a crown portion 3 and a sole portion 4. Between the toe end 2t of the face portion 2 and the heel end 2h through the back face and the shaft mounting portion 6 to which a shaft (not shown) is attached. 1 illustrates a configuration configured as a utility type head having a typical shape.

[0010] The head 1 has a hollow portion i inside,
In order to achieve a good balance between flight distance and directionality, for example, the head volume may be set to about 50 to 130 cm ³ , the loft angle α may be set to about 15 to 30 °, and the lie angle β may be set to about 57 to 60 °. Further, as a material forming the head 1, for example, one or more materials such as titanium or a titanium alloy, such as stainless steel, maraging steel, and carbon steel, can be adopted.

In the head 1 of the present invention, the boundary line La between the face portion 2 and the crown portion 3 is formed from a curve having a radius of curvature Ra of 280 to 650 mm in plan view in the reference state as shown in FIG. . Such a boundary line L
“a” has a larger radius of curvature than the conventional one.
For this reason, when the golfer holds the head 1 of the present invention, the boundary line La can be felt more linearly than before, and the boundary line La can be easily aligned perpendicularly to the target direction. Thereby, the head 1 of the present invention can be easily held.

The boundary line La is grasped by the golfer when holding it. As shown in a vertical partial cross-sectional view of the head 1 in FIG. 4A, the face portion 2 having a curvature radius Rf and the curvature radius r1 are defined. When the crown 3 intersects with a clear edge e, it is determined by the edge e. On the other hand,
As shown in FIG. 4B, the face portion 2 and the crown portion 3 have different radii of curvature rt from the respective radii of curvature of the outer surface.
Of the arc length of the arc surface 9 (9a to 9b), the face portion 2
In the toe and heel directions.

The radius of curvature Ra of the boundary line La is 28
If it is less than 0 mm, there is no great difference from the conventional one, so the effect of improving ease of holding cannot be expected. Conversely, if it exceeds 650 mm, it becomes a shape that easily causes discomfort when holding it due to the balance with the curved surface of the face round Not preferred. From such a viewpoint, the radius of curvature Ra of the boundary line La is preferably 300 to 500 mm, more preferably 300 to 400 mm,
It is particularly desirable to set the thickness to 300 to 350 mm.
The measurement of the radius of curvature Ra of the boundary line La is performed in a state where the boundary line is projected on the horizontal plane in the reference state.

Further, as shown in FIG. 1, the head 1 of the present invention includes a ridge Lb extending substantially parallel to the boundary La in the crown portion 3. In this embodiment, as shown in FIGS. 1 and 3, the crown portion 3 extends rearwardly from the boundary line La to the head with a small width and extends along the boundary line La. A small-length sub-portion 3b provided behind the portion 3a and having a concave outer surface;
b and a rear crown portion 3c having a convex outer surface.

The front crown portion 3a is formed of an arcuate curved surface whose outer surface is outwardly convex. The crown front portion 3a preferably has a curvature radius r1 of the outer surface of preferably 15 to 25 in a vertical section perpendicular to the face surface F.
It is set to 0 mm, more preferably 20 to 150 mm.
If the radius of curvature r1 of the crown front portion 3a is less than 15 mm, the crown front portion 3a becomes excessively round, the head shape is distorted, and the head tends to be hard to stand by making it difficult to visually recognize the boundary line La. On the contrary, when the radius of curvature r1 exceeds 250 mm, the crown front portion 3a is excessively flattened, so that it appears concave when held by an optical illusion or the like, giving a sense of incongruity.

In this embodiment, the sub-portion 3b has an outer surface formed of a curved surface having a radius of curvature r2 centered outside the head. The curvature radius r2 is, for example, about 15 to 250 mm,
More preferably, it is set to about 20 to 100 mm. In the head 1 of the present embodiment, the crown front portion 3
The edge line Lb is formed by an edge-like intersection of the sub-portion a and the sub-portion 3b where the curvature is reversed. The crown rear portion 3c is connected to the sub-portion 3b and smoothly connected to the head end point E.

The ridge line Lb is formed substantially parallel to the boundary line La. As shown in FIGS. 1 and 3, substantially parallel means that the distance Wa between the boundary line La and the ridge line Lb in the front-rear direction along the horizontal plane is measured at a plurality of positions in the toe and heel directions, and the maximum value Wa1 is measured. And the difference between the minimum value Wa2 (W
a1−Wa2) is in the range of 0 to 3.0 mm, and more preferably, the difference (Wa1−Wa2) is 0 to 3.0 mm.
It is particularly desirable that the thickness be 2.0 mm, more preferably 0 to 1.0 mm.

It is most desirable that the ridge line L is formed substantially parallel along the entire length of the boundary line La. However, in order to achieve the effects of the present invention, for example, the ridge line L has a total length of 50%. It suffices to have substantially parallel portions with a continuous length of at least 65%, more preferably at least 65%. As shown in FIG. 1, the radius of curvature Rb of the ridge line Lb is substantially determined by the gap Wa in the front-rear direction between the boundary line La and the ridge line Lb and the radius of curvature Ra of the boundary line La. / Rb) from 1.05
It is desirable to be about 1.20.

Further, in the present invention, as shown in FIG. 3, the distance Wa in the front-rear direction between the boundary line La and the ridge line Lb is the maximum length in the front-rear direction from the boundary line La to the rearmost point E of the head 1. Limited to 25 to 35% of the head width W. The present inventors have repeatedly conducted experiments with a large number of testers. When the interval Wa was less than 25% of the head width W, or when the interval Wa exceeded 35% of the head width W, FIG. As shown in FIGS. 5 and 6, a statistical finding was obtained that the balance of the head shape visually observed when holding the golf ball was poor, and it was difficult for many golfers to align the face surface F with the target. . Particularly preferably, the interval Wa is set to 25 to 3 of the head width W.
It is desirable to limit to 3%, more preferably 25 to 30%.

As shown in FIG. 3, the sole width SW, which is the maximum length of the head 1 in the front-rear direction, is not particularly limited, but if it is too small, the stability when the head 1 is held is inferior and the sense of security is low. If it is too large, it may give an impression that duffing is likely to occur. From such a viewpoint, the sole width SW is preferably 50 to 80 mm, more preferably 50 to 70 mm, and still more preferably 55 to 65 mm.
It is desirable that

Similarly, as shown in FIG. 1, the head length H, which is the maximum length in the lateral direction (toe heel direction) of the head,
If the size is too large, the head returns poorly and the directional stability of the hit ball tends to deteriorate, and if it is too small, it tends to give psychological anxiety. From such a viewpoint, the head length H is preferably 95 to 120 mm, more preferably 95 to 120 mm.
１１０110 mm, more preferably 100-110 mm. More preferably, the ratio (H / SW) of the sole width SW to the head length H is 1.6.
It is desirably 0 to 1.80, more preferably 1.65 to 1.78, and even more preferably 1.68 to 1.75.

The head 1 of the present embodiment as described above
Can make the boundary line La more approximate to a straight line so that the face portion 2 can be easily aligned with the target direction.
This boundary line La is located at a position away from the
By providing the ridge line Lb substantially parallel to the above, the face portion 2 can be more easily adjusted to the target direction, and the ease of holding can be further improved.

As described above, the embodiment of the present invention has been described by taking a utility type golf club head as an example. However, the present invention is not limited to such a form, and any head having a hollow portion may be used. It goes without saying that the present invention can also be applied to a wood type golf club head such as a driver. Also, the ridgeline is shown as forming a boundary between the crown front portion 3a and the sub-portion 3b, but is not limited to this, and as shown in FIG. May be formed by an arc surface having a radius of curvature different from the radius of curvature of the ridge line L in this case.
b can be determined similarly to the boundary line La.

[0024]

EXAMPLE A utility type golf club head was prototyped according to the specifications shown in Tables 1 and 2, a club having the same shaft and grip attached to the head was manufactured, and each test club was tested by four testers ( A to D) were tested for ease of holding by actually holding. In the evaluation, those that were easy to hold were evaluated as 、, those that were hard to hold were evaluated as x, and those that felt normal were none of them was evaluated as Δ. Each head is set to the same loft angle and lie angle. Tables 1 and 2 show the test results.

[0025]

[Table 1]

[0026]

[Table 2]

As a result of the test, it was confirmed that the example of the present invention was easier to hold than the comparative example.

[0028]

As described above, in the golf club head according to the present invention, the boundary between the face portion and the crown portion can be approximated to a straight line without causing a sense of incongruity, and the face portion can be moved with respect to the target direction. Easy to match. In addition, the ridgeline substantially parallel to the boundary line is provided in a well-balanced manner on the crown portion, which is separated from the boundary line by a certain distance, so that the face portion can be more easily adjusted to the target direction, and the head can be more easily set. Can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a golf club head according to an embodiment in a reference state.

FIG. 2 is a front view of the golf club head of the embodiment in a reference state.

FIG. 3 is a vertical cross-sectional view perpendicular to the outer surface of the face part in a reference state.

FIGS. 4A and 4B are schematic cross-sectional views for explaining a boundary line.

FIG. 5A is a plan view of a golf club head of Comparative Example 1, and FIG. 5B is a cross-sectional view thereof.

FIG. 6A is a plan view of a golf club head of Comparative Example 2, and FIG. 6B is a cross-sectional view thereof.

7A is a plan view of a golf club head of Comparative Example 3, and FIG. 7B is a cross-sectional view thereof.

FIG. 8A is a plan view of a golf club head of Comparative Example 4, and FIG. 8B is a cross-sectional view thereof.

9A is a plan view of a golf club head of Comparative Example 5, and FIG. 9B is a cross-sectional view thereof.

FIG. 10 is a plan view of a conventional golf club head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Golf club head 2 Face part 3 Crown part 3a Crown front part 3b Sub part 3c Crown back part La Boundary line between face part and crown part Lb Ridge Wa Wa Spacing between boundary and ridge W in front and rear direction W Head width E Head Last endpoint

Claims (2)

[Claims] 1. A plan view in a standard state in which a golf club head is mounted on a horizontal plane at a prescribed lie angle and loft angle, a boundary line between a face portion and a crown portion forming the head upper surface has a radius of curvature of 280 to 650 mm. And comprising a ridge line extending substantially parallel to the boundary line in the crown portion, and the front-back distance Wa between the boundary line and the ridge line from the boundary line to the rearmost end point of the head. A golf club head comprising 25 to 35% of the head width W, which is the length in the front-rear direction. 2. The crown portion includes a crown front portion formed between the boundary line and the ridge line, a small-length sub-portion whose outer surface is recessed behind the crown front portion, and a sub-portion. 2. The golf club head according to claim 1, further comprising a rear portion of the crown that is smoothly connected and has a convex outer surface.