JP2001321474A - Golf club head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the directivity of a hit ball. SOLUTION: The golf club head 1 comprises a face member 2 and a head body part 3 having the face member 2 mounted on the front thereof. The face member 2 comprises a material with the specific gravity thereof larger than the head body part 3. In the reference state wherein the head is placed on a horizontal surface HP at prescribed lie and loft, the head body part 3 is provided with a weight member 5 with the specific gravity thereof larger than the head body part 3 at least at a part of an area X at the rear and a lower part of the head out of four areas divided by a first plane P1 passing an intermediate point of the height of the head equivalent to the highest point of the head from the horizontal plane HP while being parallel with the horizontal plane HP and a second plane P2 passing the intermediate position between the front rim 3b1 and the rear rim 3b2 of a sole part 3b while making a vertical plane parallel with a straight line aligning the toe end and the heel end of a face side as viewed on a plane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club head capable of increasing the depth of the center of gravity and stabilizing the directionality and flight distance of a hit ball.

[0002]

2. Description of the Related Art Conventionally, as a wood type golf club head, for example, as shown in FIG. 7, a face member a and a hollow head main body portion b having the face member a disposed on the front surface and fixed thereto are provided. Together with the face member a
Is formed of a material different from that of the head body b. Since the face member a is a portion that comes into direct contact with the ball, a material having high resilience and the like, which has high strength and is suitable for increasing the flight distance of a hit ball, is used. On the other hand, for the head body b, a material having high strength and low specific gravity is generally selected in order to realize a large-sized and thinned head.

[0003] From the above viewpoint, the face member a,
When a material is selected for each head body b, the specific gravity of the material forming the face member a may exceed the specific gravity of the material forming the head body b depending on the combination of the materials. For example, there is a case where a titanium alloy (Ti-6Al-4V), which is generally used, is generally used for the head body portion b, and a material having a specific gravity of about 4.4 or more is used for the face member a. Particularly in recent years, amorphous alloys having both a very high tensile strength and a very low Young's modulus have been proposed as materials particularly suitable for the face member a. Among them, a Zr-based amorphous alloy which can be produced as a relatively large bulk material Has a specific gravity greater than that of the titanium alloy or the like because of the main component of Zr, and the combination of the materials described above may occur (for example, see JP-A-11-10).
No. 4809).

However, in a head in which the specific gravity of the face member a is larger than that of the head body b as described above,
The center of gravity G of the head approaches the face member a side, and the depth L of the center of gravity, which is the length of a normal drawn from the center of gravity G of the head to the face surface c which is the surface of the face member a, becomes small. A head having a small center of gravity L has a small moment of inertia around the center of gravity, so that the head can easily rotate around the center of gravity during a missed shot, and the directionality of the hit ball is not stable.
In addition, there is a problem that the loss of the flight distance increases.

The present invention has been devised in view of the above-described problems. The face member is formed of a material having a specific gravity greater than that of the head main body, and the face member is provided at the rear and lower part of the head main body. At least part of the area
A golf club head capable of realizing directional stability of a hit ball by increasing the depth of the center of gravity of the head and increasing the moment of inertia around the center of gravity of the head based on the provision of a weight member having a specific gravity greater than that of the head main body. It is intended to provide.

[0006]

According to a first aspect of the present invention, there is provided a golf club head comprising a face member and a head body having the face member mounted on the front surface, wherein the face member is , Made of a material having a specific gravity greater than that of the head body, and a specified lie angle,
In a reference state in which the head is mounted on a horizontal plane at a loft angle, the head main body section passes through a middle of a head height that is a height from the horizontal plane to the highest point of the head and is a first plane parallel to the horizontal plane. And a second plane which passes through an intermediate position between the front edge and the rear edge of the sole portion and is a vertical plane parallel to a straight line connecting the toe end and the heel end of the face surface in plan view. A weight member having a specific gravity greater than that of the head main body is provided in at least a part of a region behind and below the head in the two regions.

The weight member can have a weight of, for example, 5 to 90% of the weight of the face member, and a metal material having a specific gravity of 6.0 to 25.0 can be suitably used.

The face member can be made of, for example, an amorphous alloy.
-Co-Ni-Cu, Zr-Ti-Al-Ni-Cu
System, Zr-Ti-Nb-Al-Ni-Cu system, Zr-T
i-Hf-Al-Co-Ni-Cu-based or Zr-Al
-It is desirable to form from a Ni-Cu type amorphous alloy.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1 to FIG. 3 and FIG. 4 which is an AA cross section of FIG. 3, the golf club head (hereinafter, sometimes simply referred to as “head”) 1 of the present embodiment is used for hitting a ball. A face portion 2a, a crown portion 3a forming an upper portion of the head 1, a sole portion 3b forming a bottom portion of the head 1, a side portion 3c connecting between the crown portion 3a and the sole portion 3b, and a shaft (not shown) are provided. And a shaft mounting portion 3d to be inserted and fixed. Further, the head 1 of the present embodiment is substantially the same as the face 2
and a head body 3 having the face member 2 disposed on the front surface thereof, and a wood type such as a driver having a hollow portion 4 formed therein. Is exemplified. Hollow part 4
Although not shown, a foamed resin or the like can be provided as necessary.

In the present embodiment, the face member 2 has an outer peripheral edge substantially along the contour 2ae (shown in FIG. 1) of the face portion 2a, and has a substantially constant thickness t (for example, 2....
(0-4.0 mm). The surface area of the striking surface of the face member 2 is, for example, 50% of the total surface area of the face surrounded by the contour 2ae of the face portion 2a.
Or more, more preferably 65% or more, and still more preferably 8% or more.
It is desirable to set it to 0% or more, and in this example, it is set to about 90%.

The head body 3 has a concave portion 9 on the front surface in which the face member 2 fits, and also has the crown portion 3a, sole portion 3b, side portion 3c, and shaft mounting portion 3d. The shaft mounting portion 3d
Is formed in the upper part in this example, and has a pipe-like shape provided with a shaft mounting hole 3e into which a shaft (not shown) can be inserted and fixed with an adhesive or the like. And
Since the shaft center line CL of the shaft mounting hole 3e substantially coincides with the shaft center line of the shaft, in this specification, the lie angle β is determined based on the shaft center line CL.

The head body 3 of this embodiment is made of a titanium alloy (Ti-6Al-4V: specific gravity of about 4.4) having high strength and low specific gravity. Since such a head main body 3 can reduce the thickness of each part, for example, the head volume is 220 cm ³ or more, more preferably 250 cm ³ or more.
^It can be formed as a large head of ³ or more, more preferably about 270 to 380 cm ^3, which helps increase the moment of inertia of the head 1. In order to obtain such a large head, the material forming the head body 3 has a specific gravity of 1.5 to 8.0, more preferably 2.0 to 8.0.
It is preferably about 7.0 and has a tensile strength of 0.04.
0-5.0 GPa, more preferably 0.10-4.0 G
A material of about Pa can be preferably used.

The head body 3 may be integrally formed by casting including, for example, a lost wax method, or may be divided into two or more members in advance, for example, by separately forming the sole 3b. Or by forming them by welding or the like as appropriate.
The head 1 is provided with the recess 9 of the head main body 3.
The face member 2 is arranged, and both are welded, adhered,
It is formed by joining together by fixing means such as caulking. In the present embodiment, an example is shown in which both are fixed using a one-component curing type epoxy adhesive.

In the head 1 according to the present embodiment, the face member 2 is made of a material having a specific gravity higher than that of the head body 3. The face member 2 of the present example is formed of a Zr-based amorphous alloy having a specific gravity of about 6.8. Amorphous alloys are those in which the arrangement of atoms is not regular over a wide range, and have very high tensile strength and surface hardness and very low Young's modulus. When such an amorphous alloy is used as the face member 2, the thickness t of the face member 2 can be reduced and the Young's modulus is low, so that the rigidity of the face portion 2a can be reduced while maintaining strength. By reducing the rigidity of the face portion 2a, the frequency indicating the first-order minimum value of the mechanical impedance of the head 1 becomes the frequency indicating the first-order minimum value of the mechanical impedance of a general golf ball (about 600 to 1600 Hz) or the so-called impedance matching theory (Japanese Patent Publication No. 4-566).
This is preferable in that the coefficient of restitution can be increased on the basis of the above-mentioned method, the launch speed of a hit ball can be maximized, and the flight distance can be increased.

Face member 2 made of an amorphous alloy
Is described in, for example, Japanese Patent Application Laid-Open No. 11-1
It can be produced by a method as disclosed in JP 04809. That is, in a vacuum or in an inert gas atmosphere, the alloy material melted in a liquid state is pressed by a pair of upper and lower molds, and rapidly cooled at a rate higher than the critical cooling rate so that crystal nuclei are not generated and grown. Thereby, for example, the thickness t having an amorphous structure is 2 to 4 mm
The face member 2 can be formed as a plate-like material (bulk material) of a certain degree. However, when the face member 2 is formed of an amorphous alloy, how it is manufactured is not particularly limited.

Amorphous alloys having various alloy compositions exist. For example, a general formula: Ma Xb (where a and b are atomic% and 65 ≦ a ≦ 10
0, 0 ≦ b ≦ 35). Here, M is Z
r, V, Cr, Mn, Fe, Co, Ni, Cu, Ti,
Mo, W, Ca, Li, Mg, Si, Al, Pd, Be
One or more metal elements selected from the group consisting of:
It is desirable to use one composed of one or more metal elements selected from Y, La, Ce, Sm, Md, Hf, Nb and Ta.
More preferably, the a and b satisfy 99 ≦ a ≦ 100 0 ≦ b ≦ 1.

Above all, a Zr-based amorphous alloy having the highest atomic percentage of Zr in the alloy composition contained therein is desirable in that a bulk-shaped one having a good amorphous structure can be formed relatively easily. The zirconium-based amorphous alloy has a general formula: Zrc Md Xe (c, d, and e are atomic% and 20 ≦ c ≦ 80, 20 ≦ d ≦ 8
0, 0 ≦ e ≦ 35). However, Zr is zirconium, M is V, Cr, Mn, Fe,
Co, Ni, Cu, Ti, Mo, W, Ca, Li, M
g, one or more metal elements selected from Si, Al, Pd, Be, and X is Y, La, Ce, Sm, Md, H
It is made of one or more metal elements selected from f, Nb, and Ta.

The above c, d and e preferably satisfy 35 ≦ c ≦ 75 25 ≦ d ≦ 650 0 ≦ e ≦ 30, and more preferably 35 ≦ c ≦ 75 24.5 ≦ d ≦ 650. .5 ≦ e ≦ 3
0 More preferably 50 ≦ c ≦ 75 24.5 ≦ d ≦ 50 0.5 ≦ e ≦ 3
It is desirable to set to 0. M is particularly preferably Al, Cu or Ni, and X is preferably Hf. In particular, as such a zirconium-based amorphous alloy, ZrcAld1Cud2Nid3Hfe is preferable (d1 + d2 + d3 = d).

More specifically, Zr-Al-Co-Ni-
Cu-based, Zr-Ti-Al-Ni-Cu-based, Zr-Ti
-Nb-Al-Ni-Cu, Zr-Ti-Hf-Al
It is desirable to form from a -Co-Ni-Cu-based or Zr-Al-Ni-Cu-based amorphous alloy. In this example, Zr55Al10Ni5Cu30 is used for the face plate.
An example using an amorphous alloy of (atomic%) is shown.

The amorphous alloy does not necessarily have to be a completely amorphous single phase, but may be an amorphous phase in which small crystal grains are precipitated and dispersed in a small amount. For example, the degree of the amorphous phase, that is, the amorphous ratio, which is the ratio (v1 / v) of the volume v1 of the amorphous phase to the total volume v, is 50% or more, more preferably 7%.
It is desirable to use one having 5% or more, more preferably 80% or more, and more preferably 90%. The amorphous ratio can be determined by polishing the cut cross section of a metal material sample to a mirror surface, corroding the surface with an etchant, washing with water, removing the corroded film, and observing with an optical microscope. It can be specified by measuring above. Further, such an amorphous ratio, the alloy composition, the cooling rate or temperature to cool the molten alloy at the time of production, furthermore, changing the oxygen concentration in the surrounding gas when producing the amorphous metal, or performing heat treatment after molding. Can be adjusted.

If the face member 2 is made of a material having a specific gravity significantly higher than that of the head body 3, the center of gravity of the head 1 will be excessively close to the face surface 2a. For this reason, the depth of the center of gravity, which is the length of a normal drawn from the center of gravity of the head 1 to the face surface 2a, tends to be small, and the moment of inertia of the head 1 tends to be small. From this perspective,
The specific gravity of the face member 2 is, for example, about 1.5 to 8.0, more preferably about 2.0 to 7.0, and particularly, about 1.0 to 4.0 times the specific gravity of the head body 3. It is particularly desirable to stop.

In this embodiment, the weight member 5 is disposed at a predetermined position of the head main body 3 to prevent the depth of the center of gravity from becoming extremely small. That is, as shown in FIGS. 1 to 4, in the reference state where the head 1 is placed on the horizontal plane HP at a prescribed lie angle α (shown in FIG. 3) and a loft angle β (shown in FIG. 1), A first plane P1 passing through the middle of the head height h, which is the height from the horizontal plane HP to the highest point of the head 1, and being parallel to the horizontal plane HP;
The front edge 3b1 and the sole portion 3 which are the most face side 2a side
b passes through an intermediate position between the edge portion 3b2 and the rear edge 3b2 which is the most back face side, and the face portion 2 in a plan view (FIG. 3).
a second plane P, which is a vertical plane parallel to a straight line N connecting the toe end 2a1 and the heel end 2a2 of FIG.
A weight member 5 having a specific gravity greater than that of the head main body 3 is provided in at least a part of a region X behind and below the head among the four regions divided by 2.

As shown in FIGS. 4 and 5, the weight member 5 has a substantially columnar shape and is formed by forming a screw portion 5a on the outer peripheral surface thereof. The weight member 5 is detachable in, for example, a mounting hole 10 which is recessed in the side portion 3c of the head main body 3 and has a thread groove 10a formed in an inner peripheral surface thereof, for example, at a position included in the region X. And can be integrated with the head main body 3. It is to be noted that such a weight member 5 formed of a plurality of materials having the same shape and different specific gravities is prepared, and can be configured as a set so that the user can adjust the depth of the center of gravity. It goes without saying that the weight member 5 can be fixed by various methods such as press-fitting, welding, and bonding, in addition to being screwed and integrated with the head main body 3. In this example, a single weight member 5 is illustrated, but two or more weight members may be arranged.

If at least a part of the weight member 5 is not included below the head with respect to the first plane P1, the center of gravity of the head 1 tends to be high, and the backspin amount of the hit ball increases. This tends to cause a decrease in flight distance. If at least a portion of the weight member 5 is not included behind the second plane P2 in the head (on the back face side), the effect of shifting the center of gravity of the head 1 to the rear of the head is reduced.

The weight member 5 as described above is not particularly limited, but preferably has a weight of, for example, 5 to 90% of the weight of the face member 2. If the weight of the weight member 5 is less than 5% of the weight of the face member 2, it tends to be difficult to shift the center of gravity of the head 1 to the rear of the head and increase the depth of the center of gravity, and the direction of the hit ball The effect of stabilizing properties tends to decrease. Conversely, when the weight of the weight member 5 exceeds 90% of the weight of the face member 2, the depth of the center of gravity can be large, but the weight of the entire head tends to be excessively increased, and the head speed at the time of swing tends to be reduced. . From such a viewpoint, it is particularly desirable that the weight of the weight member 5 be 5 to 90%, more preferably 10 to 80%, and still more preferably 20 to 80% of the weight of the face member 2. The mass of the whole head is
For example, it is desirably 150 to 240 g.

The weight member 5 has a specific gravity of, for example, 6.0 to 25.0, more preferably 10.0 to 22.5.
It is preferred to be formed of the above metal material. The specific gravity is 6.0
If it is less than this, a relatively large volume corresponding to it is necessary to arrange the optimum weight in the head body 3,
As a result, the height of the center of gravity of the head 1 may be large.
Conversely, if the specific gravity of the weight member 5 exceeds 25.0, the material cost is likely to increase. Specifically, for the weight member 5, a heavy metal such as Mo, Ag, Pb, Ta, W, Au, Pt, and Ir, and an alloy containing at least one of these can be suitably used.

By providing the weight member 5 as described above in at least a part of the area X behind the head 1, it is useful to increase the depth of the center of gravity of the head 1, and thus to increase the moment of inertia of the head 1. As a result, the directionality of the hit ball can be stabilized, and the loss of the flight distance at the time of a miss shot can be reduced. In particular, in the case of the head 1 having a head volume of about 250 to 350 cm ³ , the depth of the center of gravity is preferably 20 to 40 mm, more preferably 25 to 35 mm. In addition, the weight member 5 of the present example exemplifies a member included in the region X without protruding from the region X. In this case, it is possible to more efficiently shift the center of gravity of the head 1 to the rear of the head 1 and, for example, to a lower side, and it is also possible to reduce the height of the center of gravity of the head.

The position of the weight member 5 is not particularly limited as long as the weight member 5 is disposed in the region X. However, in order to more efficiently shift the center of gravity of the head 1 to the rear of the head 1, as shown in this example. It is desirable that the center of gravity of the weight member 5 be substantially located on a face normal Z drawn perpendicularly to the surface of the face portion 2a from the center Fc of the face portion 2a.
The weight member 5 of this example is formed by a side portion 3c of the head main body portion 3.
And the center of gravity of the weight member 5 is substantially located on the face normal Z. The weight member 5 is desirably included within 20% of the face width W in the toe and heel directions from the face normal Z. As a result, a heavy object can be arranged on each of the face portion 2a side and the back face side in a well-balanced manner, so that the moment of inertia around the center of gravity of the head 1 can be further increased, and the directionality of the hit ball can be further stabilized. In addition, the loss of the flight distance at the time of a miss shot can be minimized. The center FC of the face portion is, as shown in FIG. 1, a point on the face surface passing through the middle between the face width W and the face thickness T.

FIG. 6 illustrates another embodiment of the present invention. In the present embodiment, the head body 3 is provided with an opening 11 on its front surface. This opening 1
1 may be along the contour of the face member 2 as shown in FIG. 6A, or as shown in FIG.
May be provided with a backup portion 12 which supports the peripheral edge of the back surface with a small width. In the head 1 shown in FIG. 6A, the weight member 5 is disposed in the hollow portion 4 and is arranged so as not to be seen from the outside of the head 1. Thereby, the appearance of the head 1 can be further improved. 6B illustrates the weight member 5 provided on the sole portion 3b of the region X.

Although the embodiment of the present invention has been described in detail above, the present invention is not limited to the illustrated embodiment, and can be variously modified. For example, the shape of the weight member 5 can be variously modified other than the columnar shape. Needless to say. The head 1 of the present embodiment is not only a wood type head, but also an iron type head.
The present invention can be applied to various heads such as a putter type, a so-called utility type having an intermediate head shape between an iron type and a wood type.

[0031]

EXAMPLE A wood-type golf club head according to the present invention (Examples 1 to 5) was prototyped, and the same shaft was attached to each head to produce a 45-inch wood-type golf club. Then, each test club is mounted on a swing robot having articulated arms, and a golf ball (Max Fly Hybrid (manufactured by Sumitomo Rubber Industries, Ltd.)) is hit at a head speed of 40 m / s to fly a ball. (Carry + Run) was measured. In order to confirm the directional stability of the hit ball, the flight distance of the hit ball was determined at the sweet spot point on the face surface (the point where the normal to the face surface drawn from the center of gravity of the head intersects the face surface). The flight distance A, which is the flight distance, and the flight distance B, which is the average value of the flight distances at respective positions shifted 10 mm in the toe and heel directions horizontally from the sweet spot point, were measured, and the difference between the two was compared. The smaller the difference is, the wider the sweet area is, the less the loss of the flight distance is at the time of a miss shot, and the better the directional stability of the hit ball is. The specifications of each head and the results of the test are shown in Table 1. The mass of each head was unified to 195 g.

[0032]

[Table 1]

As a result of the test, the result of the embodiment is shown in Comparative Example 1
The depth of the center of gravity is increased as compared with the above, and therefore the moment of inertia of the head is increased, and the difference between the flight distance A and the flight distance B is reduced. Therefore, each head of the embodiment is
It is possible to stabilize the directionality of the hit ball and minimize the loss of the flight distance even at the time of a miss shot. In Comparative Example 2, the flight distance A and the flight distance B were large because the depth of the center of gravity was large.
It was found that the flight distance A itself was small, though the difference from the distance was small. This is presumably because the head of the example had a large flight distance because the face member was formed from an amorphous alloy having excellent resilience. Note that, among the examples, Examples 2 to 5, in which the weight of the weight member was in the range of 10 to 90% of the weight of the face member, and
In Examples 3 to 5 where 0 to 90% was set, the favorable results were obtained in which the depth of the center of gravity was larger and the difference between the flight distances A and B was very small.

[0034]

As described above, according to the first aspect of the present invention, the face member is formed of a material having a specific gravity greater than that of the head main body, and at least the area defined by the head rear and lower part of the head main body. By partially providing a weight member having a specific gravity greater than that of the head body, the depth of the center of gravity of the head can be increased, the moment of inertia around the center of gravity of the head can be increased, and the directional stability of the hit ball can be realized. A golf club head may be provided.

According to the second aspect of the present invention, by setting the weight of the weight member to 10 to 90% of the weight of the face member, the weight of the head can be balanced on the face side and the back face side. Can be further increased, so that the moment of inertia around the center of gravity of the head can be further increased, and the directionality of the hit ball is further stabilized, and the loss of the flight distance at the time of a miss shot is minimized.

When the specific gravity of the weight member is limited to a certain range as described above, a sufficient mass for forming the weight member with a relatively small volume and increasing the depth of the center of gravity of the head is provided. Can be secured, and the mountability to the head main body can be enhanced. Also, as in the invention according to claim 3,

When the face member is made of an amorphous alloy, the tensile strength and surface hardness of the amorphous alloy are very high.
Utilizing a very low Young's modulus, the rigidity of the face can be reduced while maintaining strength, the restitution coefficient is increased based on the so-called impedance matching theory, and the launch speed of the hit ball is maximized to fly. The distance can be increased.

[Brief description of the drawings]

FIG. 1 is a front view of a wood-type golf club head according to an embodiment in a reference state.

FIG. 2 is a side view of the same as viewed from the toe side.

FIG. 3 is a plan view of FIG. 1;

FIG. 4 is an AA end view of FIG. 3;

FIG. 5 is an exploded perspective view of the head according to the embodiment as viewed from a sole side.

FIGS. 6A and 6B are cross-sectional views showing another embodiment of the present invention.

FIG. 7 is a cross-sectional view of a head for explaining a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Golf club head 2 Face member 3 Head main body part 5 Weight member

Claims (5)

[Claims] 1. A golf club head comprising a face member and a head body having the face member mounted on a front surface, wherein the face member is made of a material having a specific gravity greater than that of the head body. In the reference state where the head is mounted on a horizontal plane at a lie angle and a loft angle, the head main body passes through a middle of a head height that is a height from the horizontal plane to the highest point of the head and is parallel to the horizontal plane. A first plane, and a second plane which is a vertical plane passing through an intermediate position between the front edge and the rear edge of the sole portion and parallel to a straight line connecting the toe end and the heel end of the face surface in plan view. A golf club head, wherein a weight member having a specific gravity greater than that of the head main body is provided in at least a part of a region behind and below the head among the four divided regions. 2. The golf club head according to claim 1, wherein said weight member has a weight of 5 to 90% of the weight of said face member. 3. The golf club head according to claim 1, wherein the weight member is a metal material having a specific gravity of 6.0 to 25.0. 4. The golf club head according to claim 1, wherein said face member is made of an amorphous alloy. 5. The method according to claim 1, wherein the face member is made of Zr-Al-Co-.
Ni-Cu, Zr-Ti-Al-Ni-Cu, Zr
-Ti-Nb-Al-Ni-Cu, Zr-Ti-Hf
-Al-Co-Ni-Cu-based or Zr-Al-Ni-
The golf club head according to any one of claims 1 to 4, wherein the golf club head is made of a Cu-based amorphous alloy.