JP3172077B2 - Iron club head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an iron club head for a golf club.

[0002]

2. Description of the Related Art In a golf iron club head,
Designing the center of gravity closer to the toe to improve the so-called "easiness of returning the head" has been conventionally performed. Conventionally, as such an iron club, a metal member having a high specific gravity is arranged in a toe portion and the rest is formed of a metal for a general iron club head such as stainless steel or soft iron, 2. Description of the Related Art It is known that two types of metal members are used, such as a metal member having a specific gravity disposed therein and the remainder formed of a metal member having a low specific gravity such as an aluminum alloy.

[0003]

However, in the conventional iron club head as described above, the head can be easily returned, the size of the sweet area can be ensured, and the iron club head can be provided for the following reasons. It was not possible to realize an iron flap head having all of the appearance (feeling) of the iron.

When a metal member having a high specific gravity is disposed in the toe portion and the remainder is formed of a metal for a general iron club head such as stainless steel or soft iron, the appearance as a general iron club head (feet) ring)
, The head itself has to be made smaller to eliminate the weight increase due to the use of the high specific gravity metal,
As a result, the moment of inertia decreases and the sweet area also decreases.

When a metal member having a high specific gravity is disposed in the toe portion and the remainder is formed of a metal member having a low specific gravity such as an aluminum alloy, a metal having a low specific gravity is used in order to make the weight equal to that of a conventional head. Since the volume of the remaining portion has to be increased, the head has a very uncomfortable appearance.

Accordingly, the present invention provides an iron that can improve the "easiness of returning the head" while maintaining the appearance (feeling), the magnitude of the moment of inertia, and the size of the sweet area of the conventional iron club head. The purpose is to provide a club head.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, an iron club head according to the present invention has a specific gravity of a head main body of not less than 4.0 g / cm ^{3 and not} more than 10.0 g / cm ³ , and has a striking surface. the specific gravity of the part 1.7 g / cm ³ or more and 4.0g
/ A cm less than ^3, the specific gravity of the toe portion and the past and 22.0 g / cm ³ or less 10.0 g / cm ^3, further, as viewed from the front, first in contact with the toe side tip edge with a parallel to the neck axis A straight line is drawn, and a second straight line passing through the center of gravity and orthogonal to the neck axis and the first straight line is drawn.
When the point of intersection with the straight line is the first point and the point of intersection of the neck axis and the second line is the second point, the center of gravity with respect to the length of the first line segment connecting the first point and the second point The length of the second line segment connecting the point and the second point is set to 45% or more and 70% or less.

[0008], in which the length of the first line segment connecting a first point and a second point and 80mm or more and less than 100mm. Also,
The total volume is 30 cm ³ or more and 40 cm ³ or less .
Further, it is preferable that at least the toe portion is formed of a sintered metal.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

FIGS. 1, 2 and 3 show an embodiment of an iron club head according to the present invention. This iron club head comprises a head body 1, a striking surface forming section 2 and a toe section 3. It consists of three different metal members.

The head body 1 comprises a head base 7 having a recess 6 on the front surface for fitting the ball striking surface forming section 2 on the front, and a neck 4 for mounting the shaft. Ball striking face forming part 2
Is shaped like a plate, and the front surface is a face surface 5 (hitting surface). The toe portion 3 is fixed to the toe-side end of the head main body 1.

The specific gravity of the head body 1 is 4.0 g.
/ Cm ³ or more and 10.0 g / cm ³ or less, hitting surface forming part 2
The specific gravity of 1.7 g / cm ³ or more and less than 4.0 g / cm ³ ,
The specific gravity of the toe portion 3 exceeds 10.0 g / cm ³ and 22.0 g / cm ³
The following is assumed. Further, the toe portion 3 is formed of a sintered metal.

The head body 1 has a specific gravity of 4.0 g /
The material is not limited as long as it is a metal of cm ³ or more and 10.0 g / cm ³ or less, and examples thereof include titanium, titanium alloy, iron-based metal, and copper-based alloy.

The ball striking surface forming portion 2 is made of any metal as long as it has a specific gravity of 1.7 g / cm ³ or more and less than 4.0 g / cm ³ .
For example, aluminum, magnesium, beryllium, lithium, alloys thereof, and the like can be given. Further, in addition to metals, ceramics having a specific gravity of 1.7 g / cm ³ or more and less than 4.0 g / cm ³ may be used.

The toe portion 3, the material is not limited as far specific gravity of 10.0 g / cm ³ and beyond and 22.0 g / cm ³ or less of the metal, such as tungsten, tantalum, lead, molybdenum, gold,
Silver, platinum, hafnium, alloys thereof and the like can be mentioned.

As shown in FIG. 1, when viewed from the front,
A first straight line M ₁ that is parallel to the neck axis N and is in contact with the toe-side tip edge is drawn, and a second straight line M ₂ that passes through the center of gravity G and is orthogonal to the neck axis N and the first straight line M ₁ is drawn. When the intersection of the first straight line M ₁ and the second straight line M ₂ is a first point A and the intersection of the neck axis N and the second straight line M ₂ is a second point B, the first point A When relative length L ₁ of the first line segment AB connecting the second point B, the second line segment GB connecting the center of gravity G and the second point B
Of length L _2, it is 45% or more and 70% or less.

Further, the length L ₁ of the first line segment AB connecting the first point A and the second point B to 80mm or more and less than 100mm. Further, the total volume of the iron club head is 30 cm ³ or more and 40 cm ³ or less.

With the above configuration, the iron club head has the same appearance (feeling), the magnitude of the moment of inertia, and the size of the sweet area as those of the conventional general iron club head. As it is
An unprecedented position of the center of gravity closer to the toe can be realized, and so-called “easiness of returning the head” can be improved.

Therefore, it is possible to prevent slices that are often found in a beginner golfer, and to shoot with the same feeling as a conventional general iron club.

The length L ₁ of the first line segment AB connecting the first point A and the second point B is not less than 80 mm and not more than 100 mm, and
By making the total volume 30 cm ³ or more and 40 cm ³ or less,
The center of gravity can be effectively shifted toward the toe, and the appearance and the magnitude of the moment of inertia can be secured.

Further, since the toe portion 3 is formed of a sintered metal, the surface can be smoothly finished in an arbitrary shape as compared with casting. In addition, the dimensional accuracy is increased.
In addition, high density and high strength are obtained.

The specific gravity of the head body 1 is 4.0 g / cm.
³ or the specific gravity of the ball striking surface forming part 2 is 1.7 g /
If it is less than ³ cm, the total head weight becomes too light with the normal head size, so the entire head has to be made larger than usual in order to secure the normal head weight, and it looks bad and uncomfortable It becomes a head with a certain.

The specific gravity of the head body 1 is 10.0 g / cm.
If it is larger than ^3, or the specific gravity of the ball striking surface forming part 2 is 4.0 g
In the case of / cm ³ or more, the total head weight becomes too heavy with a normal head size, so the entire head has to be made smaller than usual, the moment of inertia decreases, and the sweet area becomes narrow. turn into.

When the specific gravity of the toe portion 3 is 10.0 g / cm ³ or less,
The center of gravity close to toe cannot be realized, and the head is difficult to return. It is virtually impossible for the tow portion 3 to have a specific gravity greater than 22.0 g / cm ³ .

Further, the length L ₂ of the second line segment GB to the length L ₁ of the first line segment AB is less than 45%, the head is returned hard center-of-gravity too heel closer. The length L ₂ of the second line segment GB to the length L ₁ of the first line segment AB is the greater than 70%, it is difficult to hit with sweet spot too tow closer. Further, high specific gravity metal was implanted (appearance, for feeling) when you keep the equivalent volume of the conventional head, to greater than 70% the length L ₂ to the length L ₁ is virtually Impossible.

[0026] If the length L ₁ of the first line segment AB is smaller than 80mm, the head is too small to become head difficult because the sweet spot is narrowed. The length L ₁ of the first line segment AB is greater than 100 mm, the head is too large, uncomfortable feeling (appearance, poor feeling) occurs.

If the total volume is less than 30 cm ³ , the head becomes too small, giving a sense of incongruity and a small moment of inertia, resulting in a difficult head with a narrow sweet area. On the other hand, if the total volume is larger than 40 cm ³ , the head is too large, and a sense of incongruity (appearance and poor feeling) occurs.

FIGS. 4 and 5 are cross-sectional views of another embodiment, in which a penetrating window 9 extends from the face surface 5 side to the back face 8 side in the head basic portion 7 of the head main body 1. And the hitting surface forming portion 2 forming the face surface 5 and the back face 8 is fitted into the window portion 9.
Other configurations are the same as those in FIGS.

According to this structure, the weight is further distributed to the toe portion 3 because the ratio of the volume of the striking surface forming portion 2 having a small specific gravity is increased, and the return of the head is further improved.

FIG. 6 is a cross-sectional view of another embodiment, in which a recess 10 is provided on the toe-side end surface of the head body 1 and the toe 3 is convex on the surface of the head body 1 on the head body 1 side. A tongue 3 is assembled by press-fitting or shrink-fitting a convex part 11 of a toe part 3 into a concave part 10 of a head main body part 1. Other configurations are
It is similar to that of FIGS.

According to this head, since the toe 3 on the side to be fitted into the head main body 1 is made of sintered metal, the toe 3
Dimensional accuracy can be increased, and press-fitting or shrink-fitting can be performed easily and reliably. In addition, it can be easily formed in a state of high density and high mechanical strength. Further, the degree of freedom in designing the toe portion 3 is increased, and the manufacture is facilitated.

Incidentally, the iron club head of the present invention comprises:
It is sufficient that at least the toe portion 3 is formed of a sintered metal. For example, it is preferable that the striking surface forming portion 2 and the toe portion 3 are formed of a sintered metal. The head body 1 and the toe 3
Is desirably a sintered metal. The head body 1
The hitting surface forming portion 2 and the toe portion 3 may be made of a sintered metal.

[0033]

EXAMPLE Next, a prototype club was prepared and an experiment was conducted.
Specifically, as shown in the following Table 1, the iron club heads of Examples 1, 2, 3, and 4 of the present invention and Comparative Example 1
2, 3, 4, 5, and 6 iron club heads were prepared. The loft angle and lie angle of all iron club heads were set to values corresponding to the loft angle and lie angle of a general 5-iron.

[0034]

[Table 1]

Next, the total weight and volume of the iron club heads of Examples 1, 2, 3, 4 and Comparative Examples 1, 2, 3, 4, 5, and 6, the length L ₁ of the line segment AB and the line The length L _{2 of} the minute GB,
And the length L ₂ of the line segment GB with respect to the length L ₁ of the line segment AB
Are shown in Table 2 below.

[0036]

[Table 2]

As is apparent from Tables 1 and 2, the heads of Examples 1, 2, 3, and 4 of the present invention have a specific gravity of the head body of 4.0 g / cm ³ or more and 10.0 g / cm ^3. Hereinafter, the specific gravity of the ball striking surface forming portion is 1.7 g / cm ³ or more and less than 4.0 g / cm ³ , the specific gravity of the toe portion is larger than 10.0 g / cm ³ , and
22.0 g / cm ³ or less, the length L ₂ of the second line segment GB to the length L ₁ of the first line segment AB is 45% or more and 70% or less, the first
The length L ₁ of the segment AB is 80mm or more and less than 100mm, a total volume of 30 cm ³ or more and 40 cm ³ or less, which satisfies all of the conditions.

Further, the head of the comparative examples 3, 4, 5, 6, the specific gravity of the main body, the specific gravity of the ball striking face forming portion, the specific gravity of the toe portion, the total volume, of the line segment AB a length L ₁ , and, among the ratio of the length L ₂ of the line segment GB to the length of the line segment AB, 2 or more numbers is outside the conditions of the present invention.

The head of Comparative Example 1 is a conventional iron club head formed of a single piece of stainless steel. Since the head is made of a single material, a sufficient center of gravity close to the toe cannot be realized. Specifically, the length L ₂ of the line segment GB line segment AB to the length L ₁ is 41.9 percent, which is lower than 45%.

In Comparative Example 2, since the specific gravity of the main body was small, the head had to be enlarged, and the appearance was poor.
In Comparative Example 3, since the specific gravity of the ball striking surface forming portion was large, the head had to be reduced, and as a result, a difficult head having a narrow sweet area was obtained.

In Comparative Example 4, since the specific gravity of the toe portion was small,
Sufficient specific gravity close to the toe cannot be realized, and the value of L ₂ / L ₁ is small.

In Comparative Example 5, since the specific gravity of the striking surface forming portion was small, the entire head had to be enlarged, and the appearance was poor. In Comparative Example 6, since the specific gravity of the main body was significantly large, the entire head had to be reduced, and the appearance was poor. In addition, it is a difficult head with a narrow sweet area.

Next, Examples 1, 2, 3, 4 and Comparative Examples 1,
Using a 2,3,4,5,6 iron club head, an actual hit test was performed by a human. A shaft was attached to each of the heads of Examples 1, 2, 3, 4 and Comparative Examples 1, 2, 3, 4, 5, and 6, and a grip was attached to the shaft.
The weight and swing balance of the iron club are all the same.

The subjects consisted of a total of 30 subjects, each of which was a beginner class, an average class, and an advanced class. For the test, each iron club
Ten balls were hit at a time, and the right and left swing angles of the hit ball immediately after the shot were measured and a questionnaire survey of feeling was conducted.

FIG. 6 is a bar graph showing the average launch angle of each iron club by 10 ball test hits. Note that the swing angle of the hit ball in the left-right direction is 0
°, a right angle indicates a positive angle, and a left angle indicates a negative angle.

Table 3 below shows the results of a questionnaire survey on the feeling of each iron club by trial hitting.

[0047]

[Table 3]

The results of the questionnaire survey shown in Table 3 above are summarized in Table 4 below. In addition, when the deflection angle was 0 ° or less, ○, when it was 1 ° or less, Δ, and when the deflection angle was greater than 1 °, × Also, 3 people answered that the questionnaire was favorable.
The number of persons or less was evaluated as ×, the number of persons 6 or less as Δ, and the number of persons 7 or more as ○.

[0049]

[Table 4]

According to Table 4, in Examples 1, 2, 3, and 4, the swing angle in each category (beginner, intermediate, and advanced) is small, and the questionnaire results are all ○. Therefore, it can be said that this is an extremely excellent iron club (iron club head).

Comparative Example 1 was a conventional single-material head, which had a good appearance, and the result of the questionnaire was somewhat good. However, since the head was made of a single metal material, the center of gravity was not close to the toe. The head is hard to return and the swing angle increases,
The less skillful the result, the slicing the result.

In Comparative Example 2, since the specific gravity of the main body portion was small, the entire head was large, the appearance was poor, and the questionnaire results were poor. Comparative Example 3 is a difficult head because the specific gravity of the striking surface forming portion is small, so that the entire head is downsized, and the moment of inertia is small and the sweet area is small. Therefore, the questionnaire results are poor.

In Comparative Example 4, since the specific gravity of the toe portion was small,
If the center of gravity is not sufficiently shifted toward the toe, those who are inferior in skill will slice. In Comparative Example 5, the head was enlarged because the specific gravity of the ball striking surface forming portion was small, and the appearance was poor and the questionnaire results were poor.

In Comparative Example 6, since the specific gravity of the main body was large,
The head has been downsized, making it difficult. As a result, both the swing angle and the questionnaire results were bad.

[0055]

The present invention has the following remarkable effects by the above-mentioned structure.

According to the iron club head of the first aspect, it is possible to realize a good center of gravity close to the toe, and at the same time, have a good appearance and feeling. Therefore, the iron club head can be realized in which the head is easily returned and slicing is difficult, and it is easy to hit, and the sweet area is sufficiently large.

[0057] According to an iron club head according to claim 1, wherein, it without also too large head is too small, the look easily even out, difficult to slice.

[0058] According to an iron club head according to claim 1, wherein, it without also too large head is too small, and that it too light also too heavy even without, the visible easily even out, difficult to slice.

According to the iron club head of the second aspect , since at least the toe portion 3 is made of a sintered metal, it can be finished in a free shape and a smooth surface as compared with casting. In addition, dimensional accuracy is high, and press-fitting and shrink-fitting are easy, so that it can be easily manufactured. Furthermore, the strength can be increased while the density can be increased.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a sectional side view.

FIG. 3 is a cross-sectional plan view.

FIG. 4 is a cross-sectional side view of another embodiment.

FIG. 5 is a cross-sectional plan view of another embodiment.

FIG. 6 is a cross-sectional plan view of another embodiment.

FIG. 7 is a graph showing the results of a test hit test.

[Explanation of symbols]

1 head body portion 2 hitting surface forming portion 3 toe portion A first point B second point AB first line segment GB second line segment G centroids L ₁ length L ₂ length M ₁ first straight M ₂ second linear N neck shaft center

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yoshie Takano 1-1-1, Konokita, Itami-shi, Itami-shi, Hyogo Itami Works, Sumitomo Electric Industries, Ltd. (56) References JP-A-7-255879 (JP) JP-A-5-15621 (JP, A) JP-A-7-265472 (JP, A) JP-A-63-153076 (JP, A) JP-A-7-231955 (JP, A) 63-192474 (JP, A) JP 2-20263 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) A63B 53/00-53/16

Claims (2)

(57) [Claims] 1. The specific gravity of the head body 1 is set to 4.0 g / cm ³ or more and 10.0 g / cm ³ or less, and the specific gravity of
1.7 g / cm ³ or more and less than 4.0 g / cm ³ , toe part 3
The specific gravity and the past and 22.0 g / cm ³ or less 10.0 g / cm ^3, further, as viewed from the front, pulls the first straight line M ₁ in contact with the toe side tip edge with a parallel to the neck axis N, and , Passing through the center of gravity G and the first axis M with the neck axis N.
_A second straight line M ₂ orthogonal to ₁ is drawn, and the intersection of the first straight line M ₁ and the second straight line M ₂ is defined as a first point A, and the intersection of the neck axis N and the second straight line M ₂ is defined as when the second point B, with respect to the length L ₁ of the first line segment AB connecting the first point a and the second point B, the length of the second line segment GB connecting the center of gravity G and the second point B L ₂
Is set to 45% or more and 70% or less, and the first line segment A
The length L ₁ of B is set to 80mm or more and less than 100mm, a total volume of
An iron club head having a size of 30 cm ³ or more and 40 cm ³ or less . 2. At least the toe portion 3 is formed of sintered metal.
It made that it has claim 1 iron club head according.