JP2000210400A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club head of an iron type for a long distance with which even an average golfer is able extremely easily hit a ball. SOLUTION: This upper part behind a ball hitting face is provided with a recessed part (cavity). A cavity part 8 which is enclosed by a ball hitting face part 2, a sole part 7, a back wall part 5 facing the ball hitting face part 2, etc., and of which the upper part is opened to the recessed part is formed in the lower part. As a result, the inertia moment of the head is maintained large and the head centroid is set extremely low and deep. The hit ball is easily liable to rise and the stability of directivity and a great carry may be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improving the performance of a so-called middle iron to long iron club in which the flight distance is emphasized.

[0002]

2. Description of the Related Art Clubs ranging from so-called middle irons to long irons, in which flight distance is important, are considered to be difficult for ordinary golf players to master and hard to hit. The main cause of these iron clubs is that the position of the center of gravity of the head is generally higher than the sole surface and is located in front of the face surface so that the hit ball is difficult to rise and the sweet area is narrow and it is difficult to hit the center of the face surface. Have been. Therefore, a general golfer often plays by removing this type of iron club from the golf bag.

[0003]

For this reason, recently,
The size of the iron club head is increased, the weight of the head is distributed to the periphery, the moment of inertia is increased, and the face surface is enlarged to reduce the damage, and the utility club has an intermediate shape between the wood club and the iron club. Attempts have been made to replace the club with a low center of gravity of the head and a club located at the back of the face to make it easier to raise the ball, but in the former, the direction of the ball is somewhat improved. However, it is not enough to raise the hitting ball enough to give a satisfactory flight distance, and the latter has a disadvantage that it is difficult to hit when encountering a scene where the ball is in a severe rough, etc. At present, the problem of the difficulty of striking iron clubs from long to long has not been solved.

In view of the above situation, it is an object of the present invention to provide a long-distance iron-type golf club head which is easy to hit for ordinary golf players.

[0005]

In order to achieve the above object, in a golf club head according to the present invention, a concave portion is provided in the upper rear portion of the hitting surface, and a lower portion of the hitting surface portion is provided in the lower rear portion of the hitting surface.
A cavity surrounded by a sole portion, a back wall portion facing the hitting surface portion, and a side surface of the head and having an upper portion opened to the concave portion is formed.

The loft angle of the hitting surface is set to 18 ° to 30 °, which is common for conventional middle and long iron clubs, in order to obtain a large flight distance.

In the golf club head, the thickness of the sole portion surrounding the hollow portion and the thickness of the back wall portion are appropriately adjusted in order to set the position of the center of gravity of the head at an optimum position.

[0008] In the golf club head according to the present invention, the thickness of the back wall portion may be different from the thickness at the center of the ball striking face at the toe side portion or the heel side portion or at both side portions thereof. It is set thick. As a result, the moment of inertia about a vertical axis passing through the center of gravity of the head is increased, and the directionality of the hit ball is improved.

In the golf club head of the present invention, the sole portion or a portion of the sole portion is made of a material having a higher specific gravity than that of the head body, and the manufacturing method therefor requires the sole portion of the sole from the sole side of the head body. A through-hole is formed in the sole toward the cavity, and at least a part of the sole formed separately from the head body can be fitted into the through-hole.

In the golf club head according to the present invention configured as described above, the center of gravity of the head is extremely low and the center of gravity of the head is relatively low with respect to the striking surface (that is, the face surface) while maintaining the shape of a normal iron club. Because it can be set deep behind, even a golf player of ordinary skill can easily hit a ball with a high ballistic trajectory and a wide sweet area on the face surface and a core on the face surface , It is possible to obtain a strong hit ball and increase the flight distance.

Further, since the heavy back wall portion is disposed at a distance behind the face surface via the hollow portion, the center of gravity of the head is extremely deep as compared with a normal iron club, and the center of gravity of the head passes through the center of gravity of the head. As a result, the moment of inertia about the horizontal axis increases, so that a stable loft angle (a so-called effective loft angle) at the time of hitting the ball can be obtained. As a result, variations in the flight distance are reduced.

[0012]

Embodiments of the present invention will be described below. The concave portion provided on the back surface of the hitting surface is provided with a depression similar to an existing so-called cavity iron so as to reduce the weight of the upper portion of the head so as to withstand the impact at the time of hitting.

The width of the cavity formed by being surrounded by the ball striking portion, the sole portion, the back wall, and the like at the lower portion of the back surface of the ball striking surface, which is parallel to the striking direction (the front-rear direction), is narrower at the upper side of the cavity portion and lower. It is preferably formed wide on the side. By making the cavity part like this, the sole part or a part of the sole part molded separately from the head main body is easily inserted into the head main body from the sole side, and the back wall part has its top part. Is moved forward and the bottom is moved rearward to be inclined, so that the effect of deepening the position of the center of gravity of the head can be obtained.

The relative relationship between the thickness of the back wall portion and the thickness of the sole portion according to the third and fourth aspects is such that when the center of gravity of the head is desired to be lower, the thickness of the sole portion is made relatively thicker. When it is desired to make the center of gravity deeper, the thickness of the back wall portion is set to be relatively thick.

According to a fifth aspect of the present invention, when the thickness of the back wall portion is set to be thicker at the toe side portion than at the center of the hitting surface, the moment of inertia on the toe side increases. The head easily returns during a swing, so that the so-called slice trajectory of the hit ball is corrected. Conversely, when the heel side portion is set thick, the so-called hook trajectory of the hit ball is corrected. In addition, when the toe side and the heel side are both thick, distortion of the face surface at the time of hitting the ball is extremely small, and an effect of reducing hitting damage can be obtained.

A weight having a large specific gravity and an appropriate size can be embedded in the sole fitted into the through hole provided in the sole portion. In particular, a method of casting a weight of an amorphous body such as a sintered body into the sole can be applied, and the degree of freedom in designing the weight can be expanded. Further, as a method of fixing the fitted sole to the head, various methods such as welding, press fitting, screwing, and caulking can be used.

In the golf club head according to the present invention, it is preferable that the head body is made of a titanium alloy, stainless steel, an aluminum alloy or the like, and that the sole portion is made of a metal having a high specific gravity such as a tungsten alloy.

One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a loft angle of 28 ° according to the present invention.
5 is a rear perspective view of the No. 5 iron head. FIG. In the drawing, a 3 mm-thick striking surface portion 2 made of a titanium alloy (specific gravity: 4.5) is arranged in front of the head 1. The front surface of the ball striking surface portion 2 is a ball striking surface 3 (that is, a face surface) on which the ball is struck.

A concave portion 6 surrounded by a peripheral rib 4 and a back wall portion 5 is formed in an upper portion of the rear surface of the hitting surface 3. Also,
In the lower part of the back surface of the hitting surface 3, a hitting surface portion 2, a sole portion 7, a back wall portion 5 facing the hitting surface portion 2, and a hollow portion 8 which is surrounded by the side surface of the head and has an upper portion opened to the concave portion 6 are formed. ing.

The back wall 5 has an average thickness of about 3 mm as shown in FIG. 2, which is a cross-sectional view taken along the line AA at the face center in FIG. 1, and has a toe side 9 of the head and a heel side. 10 and are arranged in a bridge. The thickness of the back wall portion 5 can be increased on the toe side or the heel side or on both sides thereof as compared with the center portion of the head to increase the moment of inertia of the thickened portion. Thus, the upper end portion 11 of the back wall portion 5 is bent toward the hitting surface side to narrow the upper opening of the hollow portion 8. Thereby, when the player looks down at the club head at the address, the opening of the hollow portion is difficult to see and a sense of incongruity does not occur. Further, since the inside of the hollow portion is difficult to see, the appearance is improved.

The sole portion 7 is provided with the hollow portion 8 from the sole side.
A through-hole 12 is formed from the toe side to the heel side, and a boat-shaped sole 14 molded separately from the head body 13 is fitted into the through-hole 12, and the periphery of the through-hole 12 is formed in the head body. The structure is fixed by welding. The sole 1
A rod-shaped weight 15 made of a tungsten alloy (specific gravity 17) is buried at the bottom of the base 4 and fixed with an adhesive.

The material of the back wall portion 5 and the sole portion 7 is the same titanium alloy as that of the hitting surface portion 2, and the head body 13 is constituted by these materials. In addition, sole 14
Is a titanium alloy in this embodiment, but may be an alloy such as copper having a high specific gravity.

The thickness of the sole portion is set in correlation with the thickness of the back wall portion 5. Here, the thickness of the sole portion 7 is an average value of thicknesses measured in a direction parallel to the hitting surface when the sole 14 is fitted to the head main body 13. For example, the thickness is measured in a direction parallel to the hitting surface at the center of the volume including the weight. The thickness of the back wall 5 is obtained by geometrically approximating the average thickness from the toe side to the heel side. In this embodiment, the average thickness of the sole 14 is set to 7 mm, which is about 2.3 times the average thickness of the back wall 5.

Since the golf club head of this embodiment is constructed as described above, the weight of the head in the central portion is reduced by the concave portion and the hollow portion, and the reduced portion is arranged in the peripheral portion, so that the center of gravity of the head is achieved. The surrounding moment of inertia is increased. In addition, the back wall is located farther rearward than the face surface due to the interposition of the cavity, so that the center of gravity of the head is set rearward, and the sweet area is enlarged. Since the center of gravity of the head is set extremely low due to the large specific gravity buried in the head, in general golf players, there is little deviation in the direction even with a slightly off-center hit, and the hit ball is high It is possible to obtain an increase in the flying distance.

In the golf club head according to the present invention, a small hole or a slit (not shown) is provided at the bottom of the back wall portion 5 so as to open rearward, so that dust and moisture accumulated in the hollow portion 8 are provided. Can be eliminated.

[0026]

In the golf club employing the golf club head according to the present invention, since the moment of inertia of the head is increased and the center of gravity of the head can be set very low and deep, it can be used by a general player with little skill. Even so, a so-called middle iron or long iron for long distance can be easily used. Further, a useful and useful club can be provided in the case of a shot on a rough turf that is deep and easily entangled or a shot that requires a distance that requires accurate directionality. Further, since the sole portion is formed separately from the head body and is fitted to the head body, there is no difficulty in assembling and manufacturing the head, and the design flexibility of the material shape of the sole portion is high. It is easy to improve club performance.

[Brief description of the drawings]

FIG. 1 is a rear perspective view showing an embodiment.

FIG. 2 is a diagram showing a cross section taken along line AA of FIG. 1;

[Explanation of symbols]

 Head Striking surface Striking surface Peripheral rib Back wall recessed sole Sole cavity Toe side Side surface on heel side Upper end through hole Head body sole Weight

Claims (7)

[Claims] A concave portion is provided on the upper rear surface of the ball striking surface, and the lower portion of the rear surface of the ball striking surface is surrounded by a ball striking surface portion, a sole portion, a back wall portion facing the ball striking surface portion, and a side surface of a head, and the upper portion is open to the concave portion. A golf club head having a hollow portion formed therein. 2. The method according to claim 1, wherein the loft angle of the hitting surface is 18 ° to 30 °.
2. The golf club head according to claim 1, wherein the angle is set to degrees. 3. The golf club head according to claim 1, wherein a thickness of a back wall portion is set to be thicker than a sole portion surrounding the hollow portion. 4. The golf club head according to claim 1, wherein a thickness of the sole portion is set to be thicker than a back wall portion surrounding the hollow portion. 5. The method according to claim 1, wherein the thickness of the back wall portion is set to be thicker at the toe side portion or the heel side portion or at both side portions thereof as compared with the thickness at the center of the hitting surface. The golf club head according to claim 1. 6. A through hole is formed from the sole side of the head body toward the cavity, and at least a part of a sole portion molded separately from the head body is fitted in the through hole. The golf club head according to any one of claims 1 to 5, wherein 7. The golf club head according to claim 1, wherein the sole portion or a part of the sole portion is formed of a metal having a specific gravity larger than that of the head main body.