PUTTER HEAD

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims priority to Japanese Patent Application No. 2024-099883 filed on Jun. 20, 2024, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a putter head.

2. Description of the Related Art

A putter used in golf is a club used mainly for hitting a golf ball on a putting green to roll the golf ball to a cup and includes a shaft attached to a putter head. In recent years, it has been proposed to mount a face insert in a face surface of the putter head to improve a hitting sensation. See Japanese Laid-Open Patent Application No. 2012-095859.

SUMMARY OF THE INVENTION

The present disclosure provides a putter head capable of improving a rolling stability of a golf ball that has been hit.

A putter head of the present disclosure includes a head body and an insert mounted in the head body. The insert includes an insert body including a first material, and an elastic member including a second material. The elastic member is disposed in a recess formed upward from a lower end portion of the insert body. The first material has a specific gravity of 2.5 or more and 4.5 or less. The second material has a specific gravity of 0.7 or more and 1.3 or less. A front surface of the insert serves as a face surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating, as an example, a putter head 1 according to a present embodiment;

FIG. 2 is an exploded perspective view illustrating, as an example, the putter head 1 according to the present embodiment;

FIG. 3 is a cross-sectional view illustrating, as an example, the putter head 1 according to the present embodiment;

FIG. 4 is an explanatory diagram (1) of an experiment for checking the spin direction caused by a putter head;

FIG. 5 is an explanatory diagram (2) of an experiment for checking the spin direction caused by a putter head; and

FIG. 6 is a partial enlarged view of a front surface 20a of an insert 20.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference symbols, and duplicate descriptions thereof may be omitted.

FIG. 1 is a perspective view illustrating, as an example, a putter head 1 according to a present embodiment. FIG. 2 is an exploded perspective view illustrating, as an example, the putter head 1 according to the present embodiment. FIG. 3 is a cross-sectional view illustrating, as an example, the putter head 1 according to the present embodiment. In FIGS. 2 and 3, an arrow d₁ indicates a toe-heel direction (left-right direction), an arrow d₂ indicates a top-sole direction (up-down direction), and an arrow d₃ indicates a face-back direction (front-rear direction).

The top-sole direction is the vertical direction in a case in which the putter head 1 rests on a horizontal plane at a reference lie angle and a reference loft angle. The top-sole direction is substantially perpendicular to the toe-heel direction and the face-back direction. Also, the toe-heel direction and the face-back direction are substantially perpendicular to each other.

The putter head 1 illustrated in FIGS. 1 to 3 has a head body 10, an insert 20, and a hosel 30.

The head body 10 includes, for example, a metal such as an aluminum alloy, a titanium alloy, a copper alloy, or stainless steel. A front surface 10a of the head body 10 is provided with a recess 10x that is recessed from the face side toward the back side. The front surface 10a can be located, for example, around the recess 10x as viewed in the face-back direction.

The insert 20 is mounted in the head body 10, for example, via an adhesive layer. Specifically, the insert 20 is disposed in the recess 10x of the head body 10, for example, via an adhesive layer. The adhesive layer is preferably, but not limited to, an epoxy-based adhesive, a rubber-based adhesive, double-sided tape, or the like.

The recess 10x and the insert 20 are shaped horizontally long in the toe-heel direction serving as the longitudinal direction. The recess 10x and the insert 20 are, for example, trapezoidal as viewed in the face-back direction. That is, the insert 20 has a shorter length on the top side than on the sole side in the toe-heel direction. Moreover, the insert 20 has a substantially constant length in the top-sole direction across all positions in the toe-heel direction.

A front surface 20a of the insert 20 is a hitting surface for hitting a golf ball and may be referred to as a face surface. The front surface 20a of the insert 20 and the front surface 10a of the head body 10, which is positioned around the recess 10x, can be flush with each other. The front surface 20a of the insert 20 can be disposed slightly inclined rather than perpendicular to the horizontal plane.

Note that the recess 10x as a whole has a uniform depth, and the insert 20 as a whole also has a uniform thickness. However, localized deep spots and thick sections, or conversely, localized shallow spots and thin sections may be incorporated.

The length of the insert 20 in the top-sole direction is, for example, 16 mm or more and 30 mm or less and preferably 18 mm or more and 25 mm or less. The length of the insert 20 in the toe-heel direction is, for example, 50 mm or more and 150 mm or less and preferably 70 mm or more and 100 mm or less. The length of the insert 20 in the face-back direction is, for example, 2 mm or more and 10 mm or less and preferably 3 mm or more and 8 mm or less. Note that there may be a gap between a side surface of the insert 20 and an inner side surface of the recess 10x. In a case in which there is a gap, the width of the gap is, for example, 0.3 mm or more and 1.5 mm or less.

The insert 20 has an insert body 21 and an elastic member 22. The insert body 21 is provided with a recess 21x formed upward from a lower end portion. The recess 21x is open on the sole side, the toe side, and the heel side of the putter head 1, but not on the top side. In other words, the insert body 21 has a cantilever structure in which the top side serves as a fixed end and the sole side serves as a free end. The length of the recess 21x in the face-back direction is, for example, 10% or more and 50% or less and preferably 25% or more and 45% or less of the length of the insert 20 in the face-back direction.

The elastic member 22 is disposed in the recess 21x of the insert body 21. On the toe side, a side surface of the elastic member 22 is, for example, flush with a side surface of the insert body 21. Moreover, on the heel side, a side surface of the elastic member 22 is, for example, flush with a side surface of the insert body 21. Furthermore, on the sole side, a lower surface of the elastic member 22 is, for example, flush with a lower surface of the insert body 21.

The insert body 21 includes a first material, and the elastic member 22 includes a second material. The first material has a specific gravity of 2.5 or more and 4.5 or less, and the second material has a specific gravity of 0.7 or more and 1.3 or less. The first material includes at least one selected from the group consisting of aluminum, titanium, and metal alloy. Moreover, the second material includes at least one selected from the group consisting of silicone, a polymer, and resin. The recess 21x of the insert body 21 can be easily

formed, for example, by cutting a raw plate of the insert 20 including the first material. Moreover, the elastic member 22 can be disposed by preparing the second material thicker than a width of the recess 21x and putting the second material into the recess 21x. For example, if the width of the recess 21x is 2 mm, the elastic member 22 can be disposed by putting the second material with a thickness of about 2.2 mm or more and 2.4 mm or less into the recess 21x. In this way, the recess 21x and the elastic member 22 can adhere to each other without a gap.

The insert body 21 may be colored by surface treatment. Coloring the insert body 21 can improve the design. For example, in a case in which the insert body 21 includes aluminum, an alumite treatment can be applied as the surface treatment. In this case, an aluminum oxide coating is formed on the surface of the insert body 21 so that the corrosion resistance and the wear resistance of the insert body 21 can be improved.

The hosel 30 is connected to the head body 10. The hosel 30 includes a shaft insertion portion 31 and a connection portion 32. The shaft is inserted into the shaft insertion portion 31, and the connection portion 32 connects the shaft insertion portion 31 and the head body 10.

The shaft insertion portion 31 is a substantially bottomed-cylindrical member and engages with the shaft. A shaft insertion hole, into which a tip portion of the shaft is inserted, is formed at the shaft insertion portion 31. The shaft insertion hole is provided so as to be offset from the connection portion 32 toward the front surface 10a of the head body 10. Titanium, titanium alloys, aluminum alloys, stainless steel, or the like can be used as the material of the hosel 30, for example.

The putter head 1 may have one or more weight adjustment parts 40 at a sole 15. In the illustrated example, the putter head 1 has two weight adjustment parts 40 at the sole 15. The weight adjustment parts 40 can be attached to or detached from the sole 15 of the head body 10, for example, by being screwed or unscrewed. Note that the putter head 1 may be without the weight adjustment parts 40.

The weight adjustment parts 40 are, for example, a metal. Examples of the metal include titanium, titanium alloys, stainless steel, aluminum, aluminum alloys, iron-based metals, magnesium, magnesium alloys, tungsten alloys, and the like. The centroid position of the putter head 1 can be adjusted by attaching and detaching the weight adjustment parts 40 to and from the head body 10.

FIGS. 4 and 5 are explanatory diagrams of experiments for checking the spin directions caused by putter heads. FIG. 4 pertains to a putter head according to a comparative example, and FIG. 5 pertains to the putter head 1. In both FIGS. 4 and 5, the front surfaces of the inserts of the putter heads were disposed parallel to the horizontal plane, and the golf balls were dropped vertically on the front surfaces of the inserts from above to check the rotations of the golf balls which were bounced on the front surfaces of the inserts and moved in the directions indicated by the arrows. Note that the putter head according to the comparative example has a structure without the recess 21x and the elastic member 22 of the putter head 1.

As shown in FIG. 4, with the putter head according to the comparative example, the golf ball bounced on the front surface of the insert hardly rotated. In contrast to this, as shown in FIG. 5, with the putter head 1, the golf ball bounced on the front surface 20a of the insert 20 rotated forward. That is, the topspin was imparted.

The reason that this result was obtained is considered as follows: when the golf ball hits the front surface 20a of the insert 20, a portion of the insert body 21, which is positioned closer to the face side from the recess 21x, slightly flexes toward the back side and then returns to the face side so that the topspin is easily imparted.

When putting with a putter including the putter head 1, as described above, the insert body 21 flexes slightly toward the back side upon hitting a golf ball and then returns to the face side. This imparts topspin more easily, enhancing the rolling of the golf ball and improving the rolling stability of the golf ball.

Moreover, since the recess 21x is open on the sole side, the toe side, and the heel side of the putter head 1, a flexure amount of the portion of the insert body 21, which is positioned closer to the face side from the recess 21x, upon hitting the golf ball can be increased compared with the case in which the recess 21x is open neither on the toe side nor the heel side. Therefore, the topspin is more easily imparted compared with the case in which the recess 21x is open neither on the toe side nor the heel side. This can further enhance the rolling of the golf ball and further improve the rolling stability of the golf ball.

Furthermore, in a case in which the insert body 21 of the insert 20 is trapezoidal as viewed in the face-back direction, the top side of the cantilever structure of the insert body 21, which serves as the fixed end, becomes shorter so that the free end side is more easily flexed. That is, when the golf ball is hit, the flexure amount of the portion of the insert body 21, which is positioned closer to the face side from the recess 21x, can be increased. Therefore, the topspin is more easily imparted compared with the case in which the insert body 21 is rectangular or the like as viewed in the face-back direction. This can further enhance the rolling of the golf ball and further improve the rolling stability of the golf ball.

Moreover, in the putter head 1, since the elastic member 22 including the second material with a lower specific gravity than that of the first material is disposed in the recess 21x, a hitting sound and a hitting sensation upon hitting a golf ball can be adjusted.

FIG. 6 is a partial enlarged view of the front surface 20a of the insert 20. As illustrated in FIG. 6, the insert 20 preferably has grooves 200 that are recessed from the front surface 20a. Each of the grooves 200 may include, for example, a first groove 201 and a second groove 202. Each of the grooves 200 may include only the first groove 201.

A plurality of first grooves 201 extend in the toe-heel direction. The plurality of first grooves 201 can be arranged, for example, at substantially equal intervals in the top-sole direction. The first grooves 201 are, for example, parallel to each other.

The lengths of the first grooves 201 in the toe-heel direction may be the same or different. The widths of the first grooves 201 in the transverse direction are, for example, 0.7 mm or more and 0.9 mm or less. The maximum depth of the first grooves 201 from the front surface 20a is preferably within 30% of the thickness of the portion of the insert body 21, which is positioned closer to the face side from the recess 21x.

One or more second grooves 202 are located between adjacent first grooves of the first grooves 201. The widths of the second grooves 202 are narrower than the widths of the first grooves 201. The maximum depth of the second grooves 202 from the front surface 20a is shallower than the maximum depth of the first grooves 201 from the front surface 20a. The second grooves 202 may include a plurality of grooves having different widths and/or different maximum depths. The widths of the second grooves 202 in the transverse direction are, for example, 0.001 mm or more and 0.003 mm or less. The maximum depth of the second grooves 202 from the front surface 20a may be, for example, about 5% of the maximum depth of the first grooves 201.

The second grooves 202 may or may not be connected to the first grooves 201. Alternatively, some of the second grooves 202 may be connected to the first grooves 201, and some of the second grooves 102 may not be connected to the first grooves 201. For example, the second grooves 202 may be arranged to extend obliquely with respect to the first grooves 201, but the second grooves 202 may be arranged to be parallel or perpendicular to the first grooves 201. Alternatively, some of the second grooves 202 may be arranged to extend obliquely with respect to the first grooves 201, and some of the second grooves 202 may be arranged to be parallel or perpendicular to the first grooves 201. The second grooves 202 are not limited to the form of a straight line, but may be bent or curved. The second grooves 202 may have a network pattern.

The first grooves 201 and the second grooves 202 can be formed, for example, by laser processing. Laser processing can form fine grooves with narrow widths and narrow pitches.

The putter head 1 with the second grooves 202 improves a frictional force between the front surface 20a and the golf ball upon hitting the golf ball. This reduces the slip of the golf ball, and the topspin is more easily imparted.

According to the disclosed technique, it is possible to provide a putter head capable of improving the rolling stability of a golf ball that has been hit.

Although the embodiments of the present disclosure have been described above in detail, the present disclosure is not limited to the above-described embodiments. Various modifications and substitutions can be made to the above-described embodiments without departing from the scope of claims.