Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wood type golf club head capable of stabilizing directionality and a golf club using the same. In recent years, the volume of wood-type golf club heads tends to increase with the improvement of manufacturing technology, and in particular, high strength and low specific gravity materials such as titanium, titanium alloys and aluminum alloys are used. Therefore, a golf club head having a head volume of 300 cc or more can be manufactured by a driver or the like. With such an increase in the size of the head, the length of the shaft also tends to increase. However, in such a golf club, as the head volume increases, the center-of-gravity distance L that is the shortest distance from the center line CL of the shaft a to the center-of-gravity point G of the head b tends to increase as shown in FIG. When the center-of-gravity distance L of the head b is increased in this way, when the ball is hit, the “bounce” of the head b tends to be deteriorated, and this tendency is remarkable particularly in combination with the long shaft. Become. Here, in a golf club with a bad head return, as shown in FIG.
In many cases, the face surface c, which is a surface for hitting the ball, does not fully return to the addressed state (usually, the face surface c is at a right angle to the target flying ball line). It is easy to hit B. For this reason, in the case of a right-handed golfer, the directionality is not stable, for example, the hit ball is launched to the right side of the target flying line, or the ball B is easily given a slice rotation that bends the ball B to the right. There is a problem of leprosy. Conventionally, in order to solve such a problem, as shown in FIG. 7, the face angle α of the face surface c is previously set on the hook side (the + side in the figure) with respect to the vertical surface N passing through the shaft center line CL. ) And setting the face angle α to be large, a method of reducing the opening of the face surface c even if the face surface c does not sufficiently return has been employed. The face angle α matches the lie angle with the specified value.
The toe i and the heel j of the face c when the shaft a is fixed in a plane perpendicular to the ground and the sole surface is attached to the ground
The angle of direction. However, in the head b having a large face angle α as described above, as apparent from the state of FIG. 7 in which the shaft a is positioned on the vertical plane N, the face Since the surface c will turn to the left,
There is also an adverse effect that it is difficult to hold the head b in the target direction. The present invention has been devised in view of the above problems. In a wood-type golf club head having a head volume of 300 cc or more, from the center line of the head shaft mounting portion to the center of gravity of the head. A wood-type golf club head capable of improving the return of the head, preventing slicing, etc., and stabilizing the direction of the hit ball, and a golf club using the same, on the basis that the center-of-gravity distance that is the shortest distance is 31 mm or less It is intended to provide. As prior art, JP-A-6-9895
No. 4 publication has been proposed. This suggests that the center of gravity position of the metal head is set on the shaft side, but this suppresses the “hook phenomenon due to the head fogging motion” and has completely different problems from the present invention. ,
There is no specific suggestion about the center of gravity distance or the head volume.  According to one aspect of the Summary of the Invention The present invention, gauze and the head body, the shaft is inserted
A wood-type golf club head having a shaft mounting portion made of a shaft-like body having a shaft mounting hole , the head volume being 300 cc or more, and the shaft center
The center-of-gravity distance L, which is the shortest distance from the center line of the shaft mounting portion coinciding with the line to the center-of-gravity point of the head, is 25 to 31 mm . The head body includes a crown portion that is continuous with the upper edge of the face portion that strikes the ball and forms the upper surface of the head, a sole portion that is continuous with the lower edge of the face portion and forms the lower surface of the head, and the crown portion and the sole portion. Including a side part extending from the toe of the face part to the heel of the face part through the back face,
It is also preferable to gradually increase the thickness of the crown part, the sole part or the side part from the toe side toward the heel side. A golf club can be provided by attaching a shaft to the shaft mounting portion of such a wood type golf club head. DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2, taking a wood golf club of a driver (# 1) as an example. FIG. 1 is a partial front view of a wood type golf club 1 of the present embodiment, and FIG. 2 is a sectional view of a head. Wood-type golf club (hereinafter, simply referred to as “club”) 1 of the present embodiment
Includes a wood type golf club head (hereinafter sometimes simply referred to as “head”) 2 and a shaft 3.
For example, a grip (not shown) is attached to one end of the shaft 3. The head 2 is a head body 2a in this example.
And a shaft mounting portion 2b to which the shaft 3 is mounted, and has a head volume of 300 cc or more.
As described above, the head is configured with a large-sized head having a volume of 300 cc or more, so that a sense of security can be obtained when the head is held and a meet rate can be increased. The head main body 2a is connected to the upper edge of the face portion 4 having the face surface 4a which is a surface for hitting a ball, and forms the upper surface of the head, and the lower surface of the head connected to the lower edge of the face portion 4. A sole portion 6 forming
It includes a side portion 7 that connects between the crown portion 5 and the sole portion 6 and extends from the toe portion t to the heel portion h through the back face. Further, the shaft attachment portion 2b is formed of a shaft-like body that is formed to protrude at a position where the face portion 4, the crown portion 5, and the side portion 7 intersect on the heel portion h side in the present example,
An example is shown in which the shaft 3 is inserted and the shaft mounting hole 9 is provided which can be fixed by, for example, an adhesive. The head volume is the total volume surrounded by the outer surface of the head 2 (including the shaft mounting portion 2b), and is actually measured by the following method. First, as shown in FIG. 3, water having a specific gravity of ρg / cc is filled in a container 10 in which the head 2 is sufficiently accommodated, and the entire container 10 is placed on the electronic balance 11 and the whole weight is measured. After that, the head 2 of the club 1 suspended in the air by a hanging tool 12 such as a wire.
The upper end of the shaft mounting portion 2b is submerged in the water of the container 10. At this time, the water surface of the container 10 rises from H1 to H2 according to the volume of the head 2. And this head 2
As the overall weight increases by the amount of water that is pushed away,
This increased weight dW is measured with the electronic balance 11. Then, the increased weight dW is divided by the specific gravity ρ of water (dW / ρ).
Thus, the volume of the head 2 can be measured. If the head volume is excessively large, the weight of the head 2 increases and it becomes difficult to swing. Therefore, the head volume is preferably set to about 300 to 350 cc, more preferably about 300 to 320 cc. Such a head 2 is made of, for example, a titanium alloy (for example, 6-4 titanium, Ti-6% Al-4%).
V alloy), and other than this, titanium alloys having other compositions , pure titanium, aluminum alloys, etc.
In addition to high strength and low specific gravity materials, various other alloys and composite materials, and other various materials such as forming the face portion 4 and the sole portion 6 with a metal material different from other portions are used. be able to. In this embodiment, as shown in FIGS. 1 and 2, the thickness of the crown portion 5, the sole portion 6 or the side portion 7 is gradually increased from the toe portion t side toward the heel portion h side. As a result, the head 2 has a center-of-gravity distance L, which is the shortest distance from the center line C of the shaft mounting portion 2b (which matches the center line CL of the shaft) to the center-of-gravity point G of the head 2, to 31 mm or less. The set items are illustrated. In the conventional head, when the head volume is 300 cc or more, the center of gravity distance is larger than 31 mm, for example, 35
Many are set to mm or more. As described above, the head 2 of the present embodiment has a sense of security when it is prepared by having a large volume of 300 cc or more.
By setting the center-of-gravity distance L to a small value of 31 mm or less, when the ball is hit, the return of the head 2 can be improved and the face surface 4a can easily return to the addressed state. Accordingly, it is possible to suitably prevent the ball from being hit with the face surface 4a being open, and to help suppress the slicing and stabilize the directionality of the hit ball. Further, since the return of the head 2 is improved, for example, it is possible to hit a so-called draw rotation (which is a rotation in the hook direction but a small degree of hook) which has an excellent flight distance, so that the directionality can be stabilized. It is effective to achieve an increase in flight distance while maintaining. Furthermore, head 2
By improving the return of the club, it is not necessary to set the face angle α of the face surface 4a in advance to a large angle on the hook side as in the prior art, and therefore the ease of holding the club 1 can be significantly improved. become. From this perspective,
The face angle α is preferably set to +2 to + 6 °, more preferably +2 to + 4 °. In the club 1 of the present embodiment, the head 2
It is possible to further increase the length of the shaft 3 and the like, and it is more effective to increase the head speed and increase the flight distance. For example, the club 1 of this example has a total length of 45 for a driver, for example.
It is possible to easily realize an increase in length of inches or more, more preferably 46 inches or more, and even more preferably 46 to 48 inches. The center of gravity distance L of such a head 2 is shown in FIG.
Can be measured using a center-of-gravity measuring instrument 15 (for example, manufactured by Kamoshita Seikosho Co., Ltd.). That is, the center-of-gravity measuring instrument 15 has an arm 16 that can swing around a horizontal axis (an axis perpendicular to the paper surface) passing through the fulcrum P.
A scale 17 is provided at one end of 6. And the head 2
The head 2 is installed so that the center line C of the shaft mounting portion 2b coincides with the fulcrum P, the head 2 is rotated around the center line C, and the arm 16 becomes horizontal and the maximum load W1 is balanced. Measure with a scale 17. If the weight of the head 2 is W2, the center of gravity distance L = (W1 / W2) × A A can be obtained from the moment balance by the length of the arm from the fulcrum P to the balance. If the center-of-gravity distance L is 31 mm or more, the effect of improving the return of the head 2 cannot be expected. On the other hand, if the center-of-gravity distance L is extremely small, the head 2 is very easy to return. For example, it is possible to hit the ball with the face surface 4a closed. Head 2
Since the moment of inertia around the center line CL of the shaft 3 is also small, the movement of the head during a miss shot tends to be large. From this viewpoint, the center-of-gravity distance L is 25
˜31 mm. In the present embodiment, the crown portion 5,
Each of the thicknesses of the sole portion 6 and the side portion 7 is illustrated as gradually increasing from the toe portion t side toward the heel portion h side. For example, in the crown portion 5, the ratio (tc2 / tc1) between the minimum thickness tc1 on the toe portion t side and the maximum thickness tc2 on the heel side is set to 1.1 to 2.0, for example. The change is performed smoothly. Similarly, in the sole portion 6, the ratio (ts) between the minimum thickness ts1 on the toe portion t side and the maximum thickness ts2 on the heel portion h side.
2 / ts1) is set to 1.1 to 2.0, for example, and the thickness is changed smoothly. Further, in the side portion 7 as well, the ratio of the minimum thickness ti1 on the toe portion t side to the maximum thickness ti2 on the heel portion h side (t
i2 / ti1) is set to 1.1 to 2.0, for example,
Examples in which these thickness changes are also performed smoothly. The present invention is not limited to such an embodiment. For example, at least one of the crown portion 5, the sole portion 6 and the side portion 7, for example, the sole portion 6 is used.
It is also possible to increase only the thickness from the toe part t side toward the heel part h side. Furthermore, the thickness also increases smoothly as in this example, and is stepped like a step. But it ’s okay. Even when the thickness of each part is uniform, for example, by a balance weight member including a synthetic resin material or a fluid disposed inside the head 2 or by improving a welding position that tends to be heavy. It is also possible to adjust the position of the center of gravity G of the head 2. Although one embodiment of the present invention has been described above, such a head 1 can be manufactured including various molding methods such as a lost wax method, casting and forging. EXAMPLE A golf club head shown in FIGS. 1 and 2 was fitted with a shaft, and a wood-type golf club (Example) according to the present invention was prototyped according to the specifications shown in Table 1. A conventional wood type golf club (comparative example) was also prototyped according to the specifications shown in Table 1 and the performance was compared. Then, using these clubs, we compared the performance by performing a ready-to-read test and a test hit test that actually hits the ball. In the test hit test, 10 right-handed low handicap golfers (handicap 0 to 10) whose hit points are relatively stable made a test shot for each club, and the directionality of the hit ball was examined. As a result of the test, as shown in Table 1, in the club of the example, 10
I feel that up to 8 of the people appear on the left and it ’s hard to slice.
It was confirmed that stable directionality was obtained. [Table 1] As described above, according to the first aspect of the present invention, it is possible to obtain a sense of security when the head volume is set to 300 cc or more, and the center of gravity distance L can be obtained.
Is set to a small distance of 31 mm or less, the return of the head when hitting the ball can be improved,
The face surface can easily return to the addressed state. Therefore, it is possible to suitably prevent hitting the ball with the face surface open, and to prevent slicing and to stabilize the directionality of the hit ball. Further, since the return of the head is improved, it is possible to hit a so-called draw-rotated ball having an excellent flight distance, which helps to achieve an increase in the flight distance while maintaining the stability of the directionality. Since it is not necessary to previously set the face angle α of the face surface large on the hook side as in the prior art, for example, it is possible to reduce the face angle and to ensure the ease of holding the club at the same time. According to the second aspect of the present invention, the thickness of the crown portion, sole portion or side portion of the head is gradually increased from the toe side toward the heel side.
The center-of-gravity distance of the head can be effectively reduced.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial front view of a golf club showing an embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating the inside. FIG. 3 is a conceptual diagram illustrating a head volume measuring method. FIG. 4 is an explanatory diagram of a method for measuring a centroid distance. FIG. 5 is a conceptual diagram illustrating a center-of-gravity distance. FIG. 6 is a conceptual diagram illustrating opening of a face. FIG. 7 is a plan view for explaining a face angle. [Description of Symbols] 1 Wood type golf club 2 Wood type golf club head 2a Head body 2b Shaft mounting part 3 Shaft 4 Face part 5 Crown part 6 Sole part 7 Side part L Center of gravity distance
─────────────────────────────────────────────────── ----- Continuation of the front page (56) References JP-A-9-271545 (JP, A) JP-A-11-57089 (JP, A) JP-A-9-28844 (JP, A) JP-A-8- 280853 (JP, A) JP 11-155592 (JP, A) JP 2000-140164 (JP, A) ACT 7-7664 (JP, U) (58) Fields surveyed (Int. Cl. 7 , DB name) A63B 53/00-53/16