Patent Application
20250205563
The present disclosure relates to a golf club head.
Patent Document 1 listed below discloses a golf club head of which sole portion is provided with a weight member. This golf club head is provided with a holding part holding the weight member in the sole portion.
The weight member has a lower surface facing a bottom surface side of the head, and a first side surface extending upward of the head from a first side of the lower surface. And the lower surface of the weight member is exposed at the bottom surface of the head. The first side surface is exposed on the sole's contour side.
In the golf club head described above, it is expected that the weight member has the effect of lowering the center of gravity of the head and allowing the center of gravity to be set at various positions closer to the outline of the sole.
However, the golf club head described above has room for further improvement in increasing the right-left MOI, which is the moment of inertia (MOI) around a vertical axis passing through the center of gravity of the head.
In view of the above-mentioned problems, the present disclosure was made, and a primary objective of the present disclosure is to provide a golf club head in which the moment of inertia such as right-left MOI can be increased while achieving the lowering of the center of gravity of the head.
According to the present disclosure, a golf club head with a hollow therein comprise: a head main body including a face portion, a crown portion and a sole portion; and a weight member fixed to the head main body, wherein
In the golf club head according to the present disclosure, therefore, the moment of inertia such as right-left MOI can be increased while achieving the lowering of the center of gravity of the head.
Hereinafter, an embodiment of the present disclosure will be described in detail in conjunction with accompanying drawings.
The drawings may contain exaggerations and dimensional ratios different from the actual ratios in order to aid the understanding of the present disclosure.
The specific configurations illustrated in the embodiment and the drawings are for understanding the present disclosure, and the present disclosure is not limited to such specific configurations.
The reference state of the head 1 is a state of the head 1 in which the head 1 is placed on a horizontal plane HP at a loft angle α (shown in
In this application, a toe-heel direction of the head 1 is a direction parallel to both the horizontal plane HP and the vertical plane VP,
Unless otherwise noted, the description assumes that the head 1 is in the reference state. As usual, the face portion 2 side is referred as the “front side” or “front”, and the opposite side is referred to as the “rear side” or “rear”.
The terms “toe” and “heel” are used in their ordinary meanings in the art.
The head 1 in the present embodiment shown in
Further, the head 1 in the present embodiment may be configured, for example, as a hybrid type and an iron type as long as the head has a hollow therein.
The head 1 in the present embodiment comprises a head main body 10 and a weight member 20 fixed to the head main body 10.
The head main body 10 in this example includes a face portion 2, a crown portion 3, and a sole portion 4, which define a hollow i inside the head.
The head main body 10 may be made of various metal materials.
Such various metal materials may include titanium, titanium alloy, stainless steel, aluminum alloy, etc.
The head main body 10 in the present embodiment is made of a titanium alloy.
The head main body 10 may be partially made of a fiber-reinforced resin.
The face portion 2 has a front surface which forms a face 2a for hitting a ball.
The face 2a may be formed as a three-dimensionally curved surface which is convex toward the outside of the head, for example.
The face 2a is provided with, for example, a plurality of grooves called face lines extending in the toe-heel direction, but these are omitted in the drawings of the present embodiment.
The face 2a is defined as the area surrounded by a peripheral edge E of the face 2a determined as follows:
In this application, the “radius of curvature” of a curved line at a certain point thereon is defined by the radius of a circle passing through three points on the curved line which are the certain point, a point on the curved line which is at a distant of 1 mm therealong toward one side of the certain point, and a point on the curved line which is at a distant of 1 mm therealong toward the other side of the certain point.
The crown portion 3 is an upper wall portion which is continuous from the face portion 2 and forms the upper surface of the head.
Specifically, the crown portion 3 is a portion which is visible from the outside of the head in the top view of the head as shown in
For example, on a heel H side of the crown portion 3, a neck portion 5 may be provided as shown in
The neck portion 5 is provided with a shaft inserting hole 5a into which the tip end of a golf club shaft (not shown) is inserted and fixed.
The center line of the shaft inserting hole 5a can be used as the above-mentioned shaft axis line CL of the golf club shaft when determining the reference state of the head from the head alone.
The center region 4C includes a bulge portion 7 which bulges downward of the head from the outer surface of the toe-side region 4A and the outer surface of the heel-side region 4B, and which extends in the front-rear direction of the head.
In the present embodiment, as shown in
As best shown in
In this way, the bulge portion 7 in the present embodiment is configured to bulge downward locally in the center region 4C of the sole portion 4.
As shown in
Further, as shown in
It is not essential but preferable that a maximum value of the height h of the bulge portion 7 is, for example, set to be not less than 3 mm, and the above-said width W is, for example, set in a range from 20 to 50 mm.
As best shown in
The recess 8 in the present embodiment is formed so as to open at the rear end surface 72 without protruding into the outer surface of the crown portion 3 and the bottom surface 71 of the bulge portion 7.
A weight member 20 is fixed to the recess 8.
The weight member 20 is made of a material having a specific gravity greater than that of the head main body 10.
As the weight member 20, preferably used is a high specific gravity metal material. For example, such high specific gravity metal material is preferably an alloy containing tungsten (W), more preferably an alloy containing tungsten (W) and nickel (Ni) and/or iron (Fe) although not particularly limited thereto.
The specific gravity of the weight member 20 is, for example, not less than 7, preferably not less than 8, and more preferably in a range from 10 to 15.
As shown in
In order to further increase the moment of inertia such as right-left MOI of the head while achieving the lowering of the center of gravity of the head, it is important that the mass is distributed more toward the periphery of the head at a lower position.
In the head 1 in the present embodiment, the bulge portion 7 is formed in the center region 4C in the toe-heel direction, of the sole portion 4.
In such bulge portion 7, the mass of the center region 4C can be distributed to a lower position of the sole portion in a concentrated manner.
On the other hand, the toe-side region 4A and the heel-side region 4B of the sole portion 4 can be considered as being relatively recessed from the bulge portion 7 toward the upper side of the head (crown portion side).
Such sole structure helps to increase a margin of the head volume with respect to the upper limit of the head volume regulated by the Golf Rules.
The increased head volume margin makes it possible to further increase the size of the bulge portion 7 and further extend the bulge portion 7 toward the rear of the head, which contributes to lowering the center of gravity and increasing the right-left MOI.
As described above, the recess 8 is formed in the rear end surface 72 of the bulge portion 7, the weight member 20 is fixed to the recess 8, and the weight member 20 is located below the crown portion 3 and above the bottom surface 71 of the bulge portion 7.
With this arrangement, the mass of the weight member 20 can be distributed to the rear of the head at a lower position. This lowers the center of gravity of the head 1 while further increasing the moment of inertia (right-left MOI).
Generally, the bottom surface 71 of the bulge portion 7 tends to come into contact with the ground during the swing of the club.
In the head 1 in the present embodiment, the weight member 20 is located above the bottom surface 71 of the bulge portion 7, namely, not located in the bottom surface 71.
In the head 1 in the present embodiment, therefore, problems during use such as damage to the weight member, falling off of the weight member, and loose fixation of the weight member can be solved over a long period of time.
More preferable aspects of the present embodiment will be described below.
In order to further increase the right-left MOI of the head 1, it is preferred that, in the top view of the head as shown in
In the structure of a typical wood-type golf club head, an area on the rear side of the head between the first and second virtual straight lines S1 and S2 can be said as a position far from the center of gravity G of the head.
Therefore, by locating the center of gravity 20G of the weight member 20 in such area, the mass of the weight member 20 can be distributed further away from the center of gravity G of the head, and as a result, it becomes possible to further increase the moment of inertia such as right-left MOI.
In this application, the face center FC means the center point on the face 2a. The face center FC is the preferred hitting position at which golfers attempt to hit the ball.
Such face center FC is determined as follows:
When, during repeating the above steps, the distance between the newly determined midpoint Py and the midpoint Py determined immediately before becomes 0.5 mm or less for the first time, the newly determined midpoint Py is considered and treated as the face center FC.
Preferably, in the top view of the head as shown in
As shown in
The first depth D defines the maximum depth of the recess 8.
The bottom surface 81 of the recess in the present embodiment is formed as a flat surface. In the present embodiment, the weight member 20 is fixed, for example, so as to come into contact with the bottom surface 81 of the recess.
The maximum thickness t of the weight member 20 from the bottom surface 81 of the recess is smaller than the first depth D.
In this example, the depth of the recess 8 and the thickness of the weight member 20 are measured perpendicularly to the bottom surface 81.
As a result, the outer surface of the weight member 20 is located closer to the hollow i side of the head 1 than the rear end surface 72 of the bulge portion 7 (including the virtual rear end surface 72a when the opening of the recess 8 is assumed to be closed).
In the case of a head such as the one disclosed in Patent Document 1, an abrasive operation or the like is required so that the outer surface of the weight member and the outer surface of the head main body become flush and continuous in order to prevent deterioration of the appearance of the head.
On the other hand, by intentionally denting the outer surface of the weight member 20 from the rear end surface 72 of the bulge portion 7 as in present embodiment, it becomes not necessary to take a abrasive operation, etc. in order to make the outer surface of the weight member 20 flush with the outer surface of the rear end surface 72 which will solve the problems in the manufacturing process.
Further, as the weight member 20 is positioned on the hollow (i) side than the rear end surface 72, the opportunities for the weight member 20 to come into contact with external objects during swing are greatly reduced. This can effectively prevent the damage, falling off, loose fixation, etc. of the weight member 20.
The weight member 20 in the present embodiment has a plate shape as shown in
The weight member 20 in the present embodiment has a first surface 21 facing toward the rear of the head, a second surface 22 facing toward the front of the head, and an outer circumferential surface 23 extending therebetween.
The first surface 21 and the second surface 22 define the plate planar direction of the plate shape, and the direction perpendicular to this is the thickness direction.
As shown in
Preferably, the width of the weight member 20 measured in the toe-heel direction is larger on the lower end 23L side than on the upper end 23U side.
In the weight member 20 in the present embodiment, each of the first surface 21 and the second surface 22 has a flattened hexagonal contour.
Such weight member 20 helps to position its center of gravity 20G further downward.
As shown, when measured in this view, it is preferable that the maximum dimension L1 of the weight member 20 in the up-down direction is be larger than the maximum dimension L2 of the weight member 20 in the front-rear direction.
In this way, by providing the weight member 20 with a vertically long shape in which the maximum dimension L2 in the front-rear direction is relatively small, the right-left MOI of the head 1 can be further effectively increased.
It is preferable that, in the vertical cross-sectional view shown in
This backwardly inclining angle θ of the weight member 20 is preferably set in a range from 10 to 30 degrees, more preferably set in a range from 15 to 25 degrees with respect to the up-down direction.
Thereby, it is possible to effectively increase the right-left MOI while achieving the lowering of the center of gravity of the head.
Incidentally, the backwardly inclining angle θ of the weight member 20 is defined as the smaller angle between the plate planar direction (A) and the up-down direction line in
The weight member 20 can be fixed to the head main body 10 in various ways.
In the present embodiment, as shown in
In this example, the weight member 20 is provided with a through hole 24 penetrating from the first surface 21 to the second surface 22.
On the other hand, the bottom surface 81 of the recess 8 is provided with a female screw portion 82 extending toward the hollow (i) and provided on the inner surface with a thread groove machined thereon.
And an male screw member 30 is inserted from the outside of the head, and passes through the through hole 24 of the weight member 20, and is fixed to the female screw portion 82 in the bottom surface 81 of the recess.
As the screw means, a so-called one-touch lock mechanism which can engage and disengage with a small rotation angle of approximately 90 degrees, can be employed as long as it can be engaged and disengaged by rotating a male or female screw portion.
In order to fix the weight member 20 to the head main body 10, other fixing means, for example, adhesive, caulking, welding and the like can be used alone or in combination, or in combination with the screw means.
In order to improve the appearance of the head 1, a badge 40 or the like on which a design, trademark, etc. is provided, may be fixed to the first surface 21 of the weight member 20.
In the present embodiment, the weight member 20 is provided with a frame-shaped protrusion formed along the outer periphery of the first surface 21, and a badge 40 is attached so as to fit into a recess surrounded by the protrusion.
In the head 1 in the present embodiment, as shown in
When a ball hits the face, usually the head 1 receives a force to rotate the head 1 around the center of gravity G
When the ball hits the face center FC in accordance with the loft angle specified for the head, the head is rotated so as to increase the loft angle, so the ball launch angle becomes increased, and the flight distance is improved.
In order to lower the center of gravity G of the head as a whole, it is desirable that the center of gravity 20G of the weight member is located below the center of gravity G of the head.
For the head 1 in the present embodiment, it is preferable that the volume of the head is in a range from 400 to 500 cc, the height in the up-down direction of the center of gravity G is in a range from 26.0 to 30.0 mm from the horizontal plane HP, and the right-left MOI is in a range from 4600 to 5500 g sq.cm.
While detailed description has been made of an embodiment of the present disclosure, the present disclosure is not limited to the above-described specific embodiment and can be embodied in various forms within the scope of the technical ideas described in claims.
More specific examples of the present disclosure will be described below.
Based on the structure shown in
The main common specifications of the golf club heads were as follows.
The computer simulation results are shown in Table 1.
In Table 1, the backwardly inclining angles θ of the respective weight members were changed with the lower left corner of the weight member in
In Comparative Example 1, the head main body had an almost same shape as Examples, but the weight member was disposed on a rear side of the head main body so that its plate planar direction became parallel with the bottom surface of the bulge portion.
Comparative Example 2 corresponded to a head obtained by removing the weight member from Comparative Example 1.
Comparative Example 3 corresponded to a head obtained by shifting the weight member of
Comparative Example 1 to the center of the sole portion in the front-rear direction.
Form the computer simulation results, it was confirmed that the golf club heads according to the present disclosure can be further increased in the moment of inertia such as right-left MOI while achieving the lowering of the center of gravity.
The present disclosure is as follows:
A golf club head with a hollow therein comprise: a head main body including a face portion, a crown portion and a sole portion; and a weight member fixed to the head main body, wherein
The golf club head according to Present Disclosure 1, wherein in a top view of the head under the reference state, the center of gravity of the weight member is located between a first virtual straight line and a second virtual straight line, wherein the first virtual straight line is a straight line drawn rearward of the head from a face center while inclining to the toe at an angle of 15 degrees with respect to a normal line to the face passing through the face center, and the second virtual straight line is a straight line drawn rearward of the head from the face center while inclining to the heel at an angle of 15 degrees with respect to the normal line to the face passing through the face center.
The golf club head according to Present Disclosure 1 or 2, wherein in a top view of the head under the reference state, the weight member is located on a normal line to the face passing through the face center.
The golf club head according to Present Disclosure 1, 2 or 3, wherein the recess has a bottom surface having a first depth, the weight member is fixed so as to be in contact with the bottom surface of the recess, a maximum thickness of the weight member from the bottom surface of the recess is smaller than the first depth.
The golf club head according to Present Disclosure 1, 2, 3 or 4, wherein the weight member has a plate shape which defines a plate planar direction and a thickness direction, and in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member, the plate planar direction is arranged along the rear end surface.
The golf club head according to any one of Present Disclosures 1 to 5, wherein in a vertical cross-sectional view of the head taken in parallel with the front-rear direction of the head through the center of gravity of the weight member, a maximum dimension of the weight member in the up-down direction is larger than a maximum dimension of the weight member in the front-rear direction.
The golf club head according to Present Disclosure 6, wherein in the vertical cross-sectional view of the head, the weight member is arranged such that the plate planar direction is inclined backwardly from the lower side to the upper side at an angle θ.
The golf club head according to Present Disclosure 7, wherein the angle θ is in a range from 10 to 30 degrees with respect to the up-down direction.
The golf club head according to any one of Present Disclosures 1 to 8, wherein the center of gravity of the head is located below the face center, and the center of gravity of the weight member is located below the center of gravity of the head.
The golf club head according to Present disclosure 2 or 3, wherein the volume of the head is in a range from 400 to 500 cc, the height in the up-down direction of the center of gravity of the head is in a range from 26.0 to 30.0 mm from the horizontal plane HP, and the right-left MOI, which is the moment of inertia around a vertical axis passing through the center of gravity of the head, is 4600 to 5500 g sq.cm.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2023-214448 | Dec 2023 | JP | national |
