1. Field of the Invention
The present invention relates to a putter head with a face insert fitted in a face portion of a head body.
2. Description of the Related Art
Conventionally, a putter head has been proposed in which a face insert made of a material different from that of a head body is fitted in a face portion of the head body. For example, JP-A-2004-236985 discloses a putter head in which a face insert having a layered structure integrally including a rubber elastic body layer, a sintered metal layer, and a fluororesin layer is fitted in the face portion of the head body. In addition, JP-A-2005-124730 discloses a putter head in which an elastic body-made face insert whose thickness increases gradually from the side of the vicinity of a sweet spot of the head toward a peripheral edge side is fitted in a face portion of a head body.
The above-described putter head with the face insert fitted in the head body is generally aimed at softening the hitting sensation when the ball is hit by the face insert.
However, with the conventional putter head with the face insert fitted in the head body, while the hitting sensation can be made soft by the face insert, the hitting sound becomes dull (low), so that there have been cases where it is difficult to grasp a sense of distance of the putt.
One aspect of the present invention provides a putter head with a face insert fitted in a head body, in which the hitting sensation at the time of hitting a ball is soft and the hitting sound is hard (high), so that it is easy to grasp the sense of distance of the putt.
According to an aspect of the invention, there is provided a putter head including: a head body having a face portion; and a face insert fitted in the face portion, the face insert including: a high-hardness portion that forms a hitting surface, and a low-hardness portion jointed to the high-hardness portion and having a hardness lower than that of the high-hardness portion.
In the putter head in accordance with the aspect of the invention, since the hardness of the high-hardness portion for forming the hitting surface (the surface for directly hitting the golf ball) is high, it is possible to obtain a hard (high) hitting sound by means of this high-hardness portion. Accordingly, it is easy to grasp the sense of distance of the putt. In addition, since the hardness of the low-hardness portion for forming a portion other than the high-hardness portion of the face insert is lower than that of the high-hardness portion, a soft hitting sensation can be obtained by this low-hardness portion.
Hereafter, a more detailed description will be given of the aspect of the invention. In the aspect, as the material of the head body, it is possible to cite, for example, stainless steel, aluminum, an aluminum alloy, brass, copper, a titanium alloy, zinc, a carbon fiber-reinforced resin, and the like, but the material of the head body is not limited to the same.
In addition, as the materials of the high-hardness portion and the low-hardness portion of the face insert, it is possible to cite synthetic resins such as an ionomer resin, a urethane resin, a urethane-based elastomer, and a polyester-based elastomer, and rubbers such as a styrene-butadiene rubber and a butadiene rubber, but the materials of the high-hardness portion and the low-hardness portion of the face insert are not limited to the same. As the materials of the high-hardness portion and the low-hardness portion of the face insert, elastomers such as a urethane-based elastomer and a polyester-based elastomer and urethane resins are particularly preferable.
In the aspect, the Shore D hardness of the high-hardness portion is set to 30 or more, more preferably 35 to 100, the Shore D hardness of the low-hardness portion is set to 10 or more, more preferably 15 to 60, and the difference in the Shore D hardness between the high-hardness portion and the low-hardness portion is set to 5 or more, more preferably 10 to 85. If the Shore D hardness of the high-hardness portion is less than 30, there are cases where a hard hitting sound cannot be obtained. If the Shore D hardness of the low-hardness portion is less than 10, there are cases where a soft hitting sensation cannot be obtained. If the difference in the Shore D hardness between the high-hardness portion and the low-hardness portion is less than 5, there are cases where the advantages of the invention of making the hitting sensation soft and making the hitting sound hard cannot be obtained.
In the aspect, one or both of the high-hardness portion and the low-hardness portion can be provided with a multi-layered structure. In a case where only the high-hardness portion is provided with the multi-layered structure, the Shore D hardness of an outermost layer which comes into contact with the golf ball in the high-hardness portion and the difference in hardness between the outermost layer and the low-hardness portion are set to the aforementioned values. In a case where only the low-hardness portion is provided with the multi-layered structure, the Shore D hardness of an innermost layer which is closest to the head body in the low-hardness portion and the difference in hardness between the innermost layer and the high-hardness portion are set to the aforementioned values. In a case where both of the high-hardness portion and the low-hardness portion are provided with a multi-layered structure, the Shore D hardness of the outermost layer which comes into contact with the golf ball in the high-hardness portion, the Shore D hardness of the innermost layer which is closest to the head body in the low-hardness portion, and the difference in hardness between the outermost layer of the high-hardness portion and the innermost layer of the low-hardness portion are set to the aforementioned values.
In the aspect, the structure of the putter head is not particularly limited, but it is possible to suitably adopt, for instance, structures shown in the following (a) to (c):
(a) A structure in which a recessed portion is formed in one of the high-hardness portion and the low-hardness portion, and the other one thereof is joined to an inner surface of the recessed portion.
(b) A structure in which the low-hardness portion of a flat plate shape is joined to one surface of the high-hardness portion of a flat plate shape.
(c) A structure in which the high-hardness portion is jointed to an inner peripheral surface of the low-hardness portion of a loop shape.
According to the putter head in accordance with the invention, the hitting sensation at the time of hitting a ball is soft, and the hitting sound is hard, so that the sense of distance is easy to grasp.
Hereafter, a description will be given of embodiments of the invention with reference to the drawings, but the invention is not limited to these embodiments.
A putter was fabricated by using a putter head in which the face insert 10 in accordance with the first embodiment shown in
Next, putting was performed by using the putter (embodiment) obtained, and the hitting sensation and the hitting sound were evaluated. As the golf balls, Tourstage X-01 manufactured by BRIDGESTONE SPORTS CO., LTD. was used. In addition, by way of comparison, similar tests were conducted by using a putter (Comparative Example 1) similar to that of the embodiment except that a recessed portion was not provided in the head body and the face insert was not fitted, a putter (Comparative Example 2) similar to that of the embodiment except that a face insert having a single-layer structure made of a urethane resin (Shore D hardness: 25) was used as the face insert, and a putter (Comparative Example 3) similar to that of the embodiment except that a urethane resin with a Shore D hardness of 60 was used for the high-hardness portion, and that a urethane resin with a Shore D hardness of 56 was used for the low-hardness portion. In Comparative Example 3, the difference in Shore D hardness between the high-hardness portion and the low-hardness portion was less than 5. The evaluation of the hitting sensation and the hitting sound was made on the basis of sensory evaluation by a plurality of golfers. The results are shown in Table 1.
From the results of Table 1, it was confirmed that, as for the putter head in accordance with the invention, the hitting sensation at the time of hitting the ball is soft, and the hitting sound is hard, so that the sense of distance is easy to grasp.
Number | Date | Country | Kind |
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P2005-314623 | Oct 2005 | JP | national |