JPH09140836A - Wood-club metal head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wood-club metal head that is further excellent in the directivity of hit balls regardless of a large head volume by setting the head volume and the depth of the center of gravity at specific values. SOLUTION: This wood-club metal head is formed into a hollow shape from a single metallic material with a small specific gravity, such as titanium, with the head volume set at 220 to 320cc. The head volume is an overall volume surrounded by the outer surface of the metal head. The thickness T1 of a face 1 is increased, and the thickness T1 of the remaining part, i.e., the thickness T2 of a sole 2 and a crown 3 is reduced to set the depth D of the center of gravity at 16 to 26mm. The depth D of the center of gravity is the length of a perpendicular M extending down from the center G of gravity of the head to the face 1. When a ball is struck at a position off the sweet spot, the wood- club metal head improves the directivity of the hit ball if the club has collided flat against the ball.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal head whose main material is a metal material among golf wood club heads.

[0002]

2. Description of the Related Art Recently, lightweight metal such as titanium has been used as a material for a metal head of a wood club, and the head volume of the club has been increased. This increases the moment of inertia around the center of gravity, reduces the rotation of the head during collision when hitting the ball at a position outside the sweet spot on the face surface of the head, and improves the directionality of the ball flight. Along with that, to widen the sweet area.

[0003]

However, due to the increase in volume of the metal head as described above, the depth of the center of gravity tends to be deeper structurally. Therefore, when the club collides flat with the ball, the launch angle of the ball in the left-right direction (the deflection angle in the left-right direction) is not so small, and there is room for further improvement in the left-right directionality.

As a result of simulations and experiments conducted by the present inventors based on the above-mentioned actual situation, the mechanical quantities of the club head relating to the direction of flight of the ball are not limited to the moment of inertia about the center of gravity of the head. However, the present inventors have found that it depends on the depth of the center of gravity.

Further, the inventors of the present invention measured the depth of the center of gravity of a head having a volume of 220 cc or more among the commercially available metal heads of the respective companies, and as a result, as is clear from Table 1 below, a conventional head volume of 220 cc or more. It was found that the depth of center of gravity of the metal head in the range of about 28 mm to 39 mm.

[0006]

[Table 1]

Therefore, the present invention relates to a metal head,
An object of the present invention is to provide a metal head for a wood club, which has a greater head volume and is more excellent in directionality of a hit ball than a conventional metal head.

[0008]

In order to achieve the above object, the metal head of the wood club according to the present invention has a head volume of 220 to 320 cc and a depth of center of gravity of 16 to.
It is set to 26 mm.

The metal head of the wood club according to the present invention has a head volume set to 220 to 320 cc, and
The thickness of the face portion and its vicinity is increased and the thickness of the remaining portion is decreased so that the depth of the center of gravity is 16 to 26 mm.

The metal head of the wood club according to the present invention has a head volume set to 220 to 320 cc, and
The specific gravity of the first material forming the face portion or its vicinity is made larger than the specific gravity of the second material forming the remaining portion, and the depth of the center of gravity D is increased.
It is configured to be 16 to 26 mm.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail based on the embodiments.

1 and 2 show an embodiment of a metal head of a wood club according to the present invention, in which 1 is a face portion,
Reference numeral 2 is a sole portion, 3 is a crown portion, 4 is a neck portion, 5 is a toe portion, 6 is a heel portion, and G is a center of gravity of the head.

However, this metal head is formed in a hollow shape from a single metal material such as titanium having a small specific gravity,
In addition, the head volume is set to 220-320cc. Here, the head volume means the entire volume surrounded by the outer surface of the metal head. In addition, the head volume is actually obtained by the following method.

First, water having a specific gravity of ρg / cc is placed in a container in which the metal head is sufficiently contained, and the container is placed on an electronic balance, and the weight of the whole is measured. After that, as shown in FIG. 5, the wood club C having the metal head H mounted thereon is suspended by a suspending tool 10 such as a wire, and the entire head H (up to the upper end of the neck portion 4) is poured into the water V of the container E. Sink in. As a result, the water level V ₂ after the head H is put in rises higher than the water level V ₁ before the head H is put in, and the total weight is increased by the amount of the water that the head H has pushed away. Then, the head volume is obtained from the equation of dw / ρ.

Further, (returning to FIGS. 1 and 2), the wall thickness T ₁ of the face portion ₁ is increased and the wall thickness T _{2 of the} remaining portion is increased.
That is, the wall thickness T _{2 of the} sole portion 2 and the crown portion 3 is reduced so that the depth of the center of gravity D is 16 to 26 mm.
The depth of the center of gravity D is the length of a perpendicular line M drawn from the center of gravity G of the head to the face portion 1.

With the above-described structure, the center of gravity G of the metal head of this wood club is located in front of the center of gravity of a conventional metal head having a head volume of 220 cc or more--that is, the depth of the center of gravity becomes shallow.

With this metal head, however, the ball is hit at a position deviating from the sweet spot--a point where the perpendicular line M drawn from the center of gravity G to the face portion 1 intersects with the face of the face portion 1--. In this case, when the club collides flat with the ball, the directionality of the flying ball is improved.

It is considered that the value of the depth of center of gravity D is 16 mm, which is the minimum design limit. In addition, the value of the depth of center of gravity D
When it is larger than 26 mm, the launch angle in the left-right direction (the deflection angle in the left-right direction) becomes large, and it becomes necessary to increase the bulge, and the trajectory draws a large arc when seen in a plan view, so the flight distance performance also deteriorates.

If the head volume is less than 220 cc, a sufficient moment of inertia cannot be obtained and the sweet area becomes narrow. At the same time, the appearance of the entire head becomes smaller, making beginners feel uneasy. In addition, 320cc is considered to be the maximum design head value.

In the illustrated example, only the wall thickness T ₁ of the face portion 1 is increased, but the wall thickness T _{1 in the} vicinity of the face portion 1 in the sole portion 2 and the crown portion 3 as well as in the face portion _1.
It is also preferable that the thickness is increased and the thickness T _{2 of the} remaining portion is decreased so that the depth of center of gravity D is 16 to 26 mm.

By the way, the depth of the center of gravity D is obtained by the following method. First, as shown in FIG. 9A, when viewed from the front, a length a of a perpendicular line drawn from a center of gravity G to a plane J orthogonal to the shaft axis N and passing through the upper end of the neck portion 4 and the shaft axis A distance (length) b between a plane including the center N and orthogonal to the plane of the paper and the center of gravity G, and a plane including the shaft axis N and orthogonal to the plane as shown in FIG. 9B. And three parameters (a, b, c) between the distance (length) c from the center of gravity G and the center of gravity G. That is, the center of gravity is
It is defined by three parameters (a, b, c).

To measure the parameters (a, b, c), a center of gravity measuring device (for example, manufactured by Kamoshita Seikosho Co., Ltd.) is used.
The principle is as follows. As shown in (a) of FIG. 10, a head H is attached to one end of an arm 21, which is swingable around a horizontal axis passing through a fulcrum P, and a scale 20 connected to the other end of the arm 21 Find the weight W ₁ . In addition, the head weight W ₂ is measured in advance. Then, W ₁ × L = W ₂ ×
Since the expression of a is established, the value of the length a can be calculated.

Further, as shown in (b) of FIG.
Change the mounting direction of the head H to 21 and obtain the weight W ₁ . Then, since the formula of W ₁ × L = W ₂ × b is established, the value of the length b can be calculated.

Further, as shown in FIG. 10C, the direction in which the head H is mounted on the arm 21 is changed to obtain the weight W ₁ . Then, since the formula of W ₁ × L = W ₂ × c is established, the value of the length c can be calculated.

Further, as shown in FIG. 11, a face S of the head H (face portion 1) is set downward, and a point S at which the overall balance is obtained is obtained. The length d of the perpendicular drawn from the point S to the plane Q including the sole surface is measured with a caliper or the like.
(At this time, the lie angle is set as a set angle so that the contact surface of the face surface is perpendicular to the ball traveling direction.)

Further, as shown in FIG. 12, when the head H is viewed from the side, a distance e (face progression) from the shaft axis N to the leading edge is obtained. At this time, the lie angle is set to a set angle, and the contact surface of the face surface is made flat so that it is perpendicular to the ball traveling direction.

Next, the length L ₂ is calculated in the simplified diagram of FIG. That is, L ₂ = tan θ × d. Here, θ is a loft angle, c is one of the above parameters, and is the distance from the shaft axis N to the center of gravity G when the head is viewed from the side, e is face progression, and L ₁ is e and c. , D is the depth of the center of gravity, and d is the height of the point S.

Therefore, according to FIG. 14, for the depth of the center of gravity D, the formula of D = (L ₁ −L ₂ ) / cos θ holds. Further, as described above, L ₁ = c + e and L ₂ = tan θ × d
Therefore, D = {(c + e) − (tan θ × d)} / c
It becomes osθ, and the depth of center of gravity D can be calculated.

Next, FIGS. 3 and 4 show another embodiment. In this metal head, the face portion 1 and the neck portion 4 are formed of the first material 7 and the remaining portion is the second material. It was formed in 8.

However, the first material 7, 7 and the second material 8 are both metal, and the specific gravity of the first material 7, 7 is made larger than the specific gravity of the second material 8, that is, the first material. As the metal 7 and 7, a metal having a larger specific gravity than the metal of the second material 8 is used, and the depth of the center of gravity D is set to 16 to 26 mm.

The head volume is set to 220 to 320 cc. The thickness T ₁ of the face portion 1 of this metal head
The thickness T _{2 of the} remaining portion is set to be substantially the same as that of the metal head shown in FIGS.

With the above structure, the depth of center of gravity D of this metal head becomes smaller than that shown in FIGS.

As the first material 7, 7 and the second material 8, it is preferable to use a metal having a large difference in specific gravity and sufficient strength. For example, tungsten is used as the first material 7, 7. It is also desirable to use titanium as the second material 8. Of course, other metals can be used freely.

Further, in the illustrated example, the entire neck portion 4 is made of the first material 7, but it is also possible to make a part of the neck portion 4 the second material 8. Alternatively, only the face portion 1 may be formed of the first material 7, and the remaining portion including the sole portion 2, the crown portion 3, and the neck portion 4 may be formed of the second material 8. Alternatively, the face portion 1 and portions of the sole portion 2 and the crown portion 3 in the vicinity of the face portion 1 may be formed of the second material 8.

The metal head shown in FIGS. 1 to 4 is formed in a hollow shape, but the hollow portion may be filled with a lightweight material such as foamed resin. Further, in the illustrated example, the thickness T ₁ of the face portion 1 or its vicinity and the thickness T _{2 of the} remaining portion are respectively
Although the wall thickness is substantially uniform, the wall thickness does not necessarily have to be uniform.

Next, simulations and experiments conducted to verify the effect of the metal head of the present invention will be described.

As a simulation, a head model H ′ having depths of the centers of gravity of 16 mm, 20 mm, 26 mm, 30 mm and 40 mm, respectively.
For the above, the relationship between the lateral distance from the sweet spot at the hitting position and the deflection angle in the lateral direction of the ball (left and right flight directions) was calculated using the depth of the center of gravity of the head as a parameter.

6 and 7, the value of the depth of the center of gravity is 30 mm, respectively.
And a head model H'of 40 mm and a golf ball model B '. F is the face portion, 30 is the toe portion side, and 31 is the heel portion side. The depth of center of gravity values are 16mm, 20mm, and 26mm.
Are omitted from the drawing.

The head model H'has its weight and the moments of inertia about the axial center in the up-down direction, the left-right direction, and the front-rear direction passing through the center of gravity G set in the same manner as in a general wood club head. Values other than (depth of center of gravity) were not changed. Also, the bulge radius is 14 inches,
The loft was 0 °. The collision speed when the head model H ′ hits the ball model B ′ was 45 m / s.

The result of the above simulation is shown in the graph of FIG. From FIG. 8, it can be said that when the depth of the center of gravity is small (shallow), the deflection angle of the flying ball in the left-right direction is small and the directionality is good.

[0041]

EXAMPLES Next, a trial club was prepared and an experiment was conducted.
Specifically, a conventional metal head as shown in Table 2 below was prepared, and a metal head as an example of the present invention was prepared.

[0042]

[Table 2]

The structure of the head was made of a single metal material as in FIGS. 1 and 2. Specifically, titanium having a specific gravity of 4.3 g / cm ³ was used as the metal material. The face wall thickness is 6.2 mm, the crown wall thickness is 1.5 mm, and the sole wall thickness is 1.6 mm.

Further, the structure of the head and the head is made of two kinds of metal materials similarly to those of FIGS. Specifically, tungsten having a specific gravity of 19.3 g / cm ³ was used as the first material forming the face and neck portions, and titanium having a specific gravity of 4.3 g / cm ³ was used as the second material forming the balance. The thickness of each portion was set to be substantially the same as that of the head.

As a conventional head, the product name "TANGENT Titanium 270c" manufactured by Sumitomo Rubber Industries, Ltd. is used.
The metal head of "c" was used. Further, the outer shape of the embodiment is the same as that of the conventional head.

With respect to the above-described conventional head and the above-described head, the sweet spot was used as the reference point A, and the reference hit point A and the hit point B 20 mm away from the reference hit point A toward the toe side. The flight direction (deflection angle in the left-right direction) at that time was measured.

In order to match the impact conditions, the same shaft (Sumitomo Rubber Industries, Ltd .: trade name FECT V510: carbon shaft R) was attached to the heads of the conventional example and the example. A swing robot is used for striking, and the head speed is 40 m.
/ S. And the value of the deflection angle at one hit point is
With the deflection to the toe side being a positive value, the average of the measured values of five hits was taken. The results are shown in Tables 3 and 4 below.

[0048]

[Table 3]

[0049]

[Table 4]

From the above Tables 3 and 4, the head of the embodiment of the present invention, which has a smaller depth of center of gravity than the conventional example, has a smaller difference in the deflection angle of the hitting point AB and a lateral deviation of the flying ball position. It can be seen that the directionality of the flying ball is good. Further, in the examples, the smaller the depth of the center of gravity, the smaller the difference between the deflection angles of the hit points AB, and the better the directionality of the flying ball.

As is clear from Table 4, the carry (flying distance) value of the head of this embodiment is larger than that of the conventional example. Further, in the examples, the smaller the depth of the center of gravity, the larger the value of carry (flying distance). Therefore, according to the present invention, not only the directionality can be improved, but also the effect of increasing the flight distance can be obtained.

[0052]

The present invention has the following remarkable effects by the above-mentioned structure.

According to the metal head of the wood club of the first aspect, the head collides flat with the ball at a position deviated from the sweet spot to the left and right as compared with the conventional metal head having a head volume of 220 cc or more. At this time, the deviation of the flying ball in the left-right direction can be reduced (compared to the metal head of the conventional wood club), and the directionality is improved.

According to the metal head of the wood club of the second aspect, the same effect as that of the first aspect can be obtained, and the whole head can be formed of a single metal material, and the structure is simple. Becomes And it is easy to manufacture.

According to the metal head of the wood club of the third aspect, the same effect as that of the first aspect can be obtained, and the depth of the center of gravity D can be easily reduced by design. further,
Greater flexibility in design and design.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a sectional side view.

FIG. 3 is a plan view showing another embodiment.

FIG. 4 is a sectional side view.

FIG. 5 is an explanatory diagram of a head volume measuring method.

FIG. 6 is a plan view of a head model and a ball model for simulation.

FIG. 7 is a plan view of a head model and a ball model for simulation.

FIG. 8 is a graph showing the result of simulation.

FIG. 9 is a simplified explanatory view of the position of the center of gravity.

FIG. 10 is a simplified diagram illustrating the principle of the center-of-gravity measuring device.

FIG. 11 is an explanatory diagram of a method of measuring the position of a sweet spot.

FIG. 12 is an explanatory diagram of a method of measuring face progression.

FIG. 13 is a simplified explanatory diagram for obtaining the depth of the center of gravity.

FIG. 14 is a simplified explanatory diagram for obtaining a depth of the center of gravity.

[Explanation of symbols]

1 Face part 7 1st material 8 2nd material D Center of gravity depth T ₁ thickness T ₂ thickness

Claims (3)

[Claims] 1. A metal head for a wood club, wherein the head volume is set to 220 to 320 cc and the depth of center of gravity D is set to 16 to 26 mm. 2. The head volume is set to 220 to 320 cc, the thickness T ₁ of the face portion 1 or its vicinity is increased, and the remaining thickness T ₂ is reduced to obtain a depth of gravity D of 16 to 26.
A wood club metal head characterized by being configured to be mm. 3. The head volume is set to 220 to 320 cc, and the specific gravity of the first material 7 forming the face portion 1 or the vicinity thereof is made larger than the specific gravity of the second material 8 forming the remaining portion so that the depth of the center of gravity is increased. A wood club metal head characterized by having a D of 16 to 26 mm.