JPH11267251A - Golf club - Google Patents

Abstract

(57) [Summary] [Problem] To provide a golf club in which the return of the head by the rotation of the head around the shaft axis during a swing is effectively utilized to improve the flight distance, and furthermore, the direction can be stabilized. The purpose is to do. A golf club according to the present invention includes a head having a sweet spot center position in an area on a heel side of a center position C of a face surface 2 and in an area below the center position C. And

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a golf club.

[0002]

2. Description of the Related Art A point at which the head used in a golf club intersects with a perpendicular line from the center of gravity of the head to the face, that is, a so-called sweet spot, is usually located at the center of the face of the head. A score line formed on the face surface may be provided with a feature or a pattern that allows the position to be recognized may be formed on the face surface so that the position of the sweet spot can be recognized.

[0003] In general, golf players
When hitting the ball, he swings to catch the ball at the sweet spot of the head. That is, the player swings to catch the ball at the characteristic portion of the score line as described above and a separately formed pattern (hereinafter, referred to as a pattern). Even if such a pattern is not formed, the player generally recognizes that the center (face center) of the face surface of the head is a sweet spot, and tries to catch the ball at the face center. Swing. This is because the position of the above-mentioned face center is the sweet spot, and it is believed that the ball will hit the longest distance when hit at this point.

[0004]

However, the return of the head due to the rotation of the head around the axis of the shaft during the swing is effectively used to improve the flight distance of the ball, and the trajectory of the hit ball is increased to increase the flight distance. Contains the conditions described above,
That is, it was found that it was not enough to hit (swing) the ball at a position recognized as a sweet spot.

It is an object of the present invention to provide a golf club capable of improving the flight distance and effectively stabilizing the direction by effectively utilizing the head return caused by the rotation of the head around the shaft axis during a swing. With the goal.

[0006]

In order to solve the above-mentioned problems, a golf club according to the present invention has a sweet spot center position in an area heel side of the center position of the face surface and below the center position. Characterized by having a head formed with.

A golf club according to the present invention is a head having a pattern formed on a face surface so that a center position of a hit ball can be recognized.
And a head having a sweet spot center position formed in an area below the center position of the pattern.

[0008]

SUMMARY OF THE INVENTION As described above, the head used in the golf club of the present invention has a new point which will be described in detail below. The heel side and the sole side are formed with respect to the pattern center position indicating the position.

When the golf club swings (with the sweet spot positioned on the heel side), at the time of impact, a rotational force about the shaft acts on the head by turning the wrist. Normally, the centrifugal force causes the center of gravity to shift slightly to the tip side due to the action of this rotational force. Therefore, the ball is caught slightly to the tip side from the center of gravity (sweet spot) in the actual stationary state. It is possible to improve the flight distance. Specifically, taking a baseball bat as an example, when a baseball bat is swung, the point at which a so-called true core is likely to come out of a home run has shifted slightly from the position of the center of gravity of the bat in a stationary state to the front end side. Position. This is because, when the bat is swung, the centroidal force acting on the bat is considered to shift the actual position of the center of gravity to the tip side, and therefore, during the actual swing, by catching the ball at that position, A longer flight distance can be obtained.

[0010] Therefore, even in a golf club, since the turning force around the axis of the shaft is exerted by the return of the wrist at the time of the swing, it is more difficult to catch the ball on the tip side than the actual sweet spot. Can improve the flight distance. Normally, when a pattern for recognizing a sweet spot is formed on the center of the face or on the face, the golfer swings to capture the ball at that position. For this reason, by setting the actual sweet spot position on the heel side of the center of such a face or the position where the pattern is formed, at the time of actual impact,
It becomes easy to catch the ball at a position where the flight distance can be obtained most.

(Regarding the position of the sweet spot on the sole side) As described above, by setting the position of the sweet spot on the heel side, the distance of the center of gravity from the axis of the shaft is shortened. Makes the head easier to return. In other words, the face is easily covered with the ball, resulting in a low trajectory or a hook ball.

For this reason, by lowering the sweet spot position, it is easy to hit a ball at a position higher than the sweet spot, so that a relatively high ball is easily made to come out, thereby reducing the influence of the face fogging. deep.

The sweet spot can be formed at the position described above by appropriately selecting the constituent material of the head, changing the head shape, adding a weight member, and the like.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1A shows a wood type head, and FIG. 1B shows an iron type head.

In the case of the wood type head 1, the center position C of the face surface 2 is determined as follows. In the face surface 2 on the front surface of the head, the portions (toe side P1 and heel side P2) farthest from the lie angle reference line in the horizontal direction are determined, and perpendiculars X1 and X2 to the lie angle reference line are determined from the positions. Lower. The center line X of the perpendiculars X1 and X2 is the center position in the toe-heel direction, and points P3 and P4 where the center line X and the edge of the face surface 2 intersect.
Is a face center C (a line parallel to the lie angle reference line passing through the face center C is indicated by Y).

In the case of the wood type, the head 1 may be designed so that the sweet spot is located on the heel side and the sole side of the face center C determined as described above. Note that the actual hit ball is ± 10 mm in the vertical direction around the face center C,
Since the adjustment is often performed within a range of ± 15 mm in the toe-heel direction, it is preferable to design the head such that the center of the sweet spot is located in a region indicated by oblique lines in the drawing.

In the case of the iron type head 10, the center position C of the face surface 12 is determined as follows. On the face surface 12, a toe-side tip of the face surface 12 and a heel-side base end where the face surface is flat are defined, and perpendiculars X1 and X2 to the lie angle reference line are lowered from the positions. The center line X of the perpendiculars X1 and X2 is the center position in the toe-heel direction. The point at which the straight line Y parallel to the lie angle reference line Y1 at a predetermined height d (= 18 mm) from the lie angle reference line Y1 intersects the center line X is the face center C.

In the case of the iron type, the head 10 may be designed such that the sweet spot is located on the heel side and the sole side of the face center C determined as described above. The actual hit ball is
± 7mm in the vertical direction around the face center C,
Since the adjustment is often performed within a range of ± 10 mm in the toe-heel direction, it is preferable to design the head such that the center of the sweet spot is located in a region indicated by oblique lines in the drawing.

FIGS. 2 (a) and 2 (b) show a wood type head having a pattern formed on the face so that the center of the hit ball can be recognized. The head 20 shown in (a) has a dot pattern formed in the center region of the face surface 22 so as to have a rhombus shape, and (b)
The head 30 indicated by a symbol has a pattern formed by dividing score lines in a central region of the face surface 32 so that a rhombus can be visually observed. Each pattern is formed so that the golfer is conscious of hitting the ball at the center C of the pattern.

In this type of head as well, the actual center position of the sweet spot is located on the heel side of the straight line X passing through the center C (perpendicular to the lie angle reference line).
In addition, it is designed to be located in an area (sole side) below the straight line Y (parallel to the lie angle reference line). In addition,
The center position of the sweet spot actually formed is shown in FIG.
It is preferable to set the hit area as shown by the diagonal lines in FIG.

As described above, when a golf club is swung, a rotational force about the shaft acts on the head when the golf club is impacted by turning the wrist. Power hitter players tend to be larger. Therefore, it is preferable to set the sweet spot at an optimum position according to the subject. Specifically, for example, consider the case where the player's ability is divided into four stages of hard hitter, average hitter, senior, and ladies, and a desirable range of distance L (the center position C to the sweet spot position on the heel side from each position) is considered for each stage. The distance to S; see FIG. 3) is shown below.

A club for a hard hitter (as a guide, the flex indication of the shaft is equivalent to "S" or "R" and "S"
L between 3.5 and 7.0.
It is good to be 5 mm. Average hitter clubs (As a guide, the shaft flex display is equivalent to "R")
In this case, L is preferably set to be 3.0 to 7.0 mm. Club for seniors (As a guide, the flex indication of the shaft is equivalent to "A" or "AR", "R" between "A" and "R"
A)), L is preferably set to be 2.5 to 6.5 mm. In the case of a women's club (as a guide, the flex display of the shaft is equivalent to "L" or softer), L is preferably set to 2.0 to 6.0 mm.

When the head is designed as in the present invention, a more stable height and direction of the ball muscle can be obtained by using a shaft having a large deflection angle measured as described later. In other words, by using a shaft with a large deflection angle, the launch angle at the time of impact of the ball increases, so it is possible to reduce the real loft angle and reduce the back spin amount, resulting in further improvement of the flight distance. Can be planned. Specifically, it is preferable to use a shaft having a deflection angle of 10.8 degrees or more, preferably 11.2 degrees or more. However, if the deflection angle is too large, the tendency of toe-down becomes large and it becomes difficult to control the head.
It is preferable that the temperature is not more than the degree. Further, such a shaft having a large deflection angle also has a surface in which the toe-down is increased, but since the head of the present invention has a shorter distance from the shaft axis to the center of gravity, the toe-down can be suppressed,
As a result, the ball can be effectively used and the ball can be easily lifted.

The measurement of the deflection angle of the shaft is shown in FIG.
The measurement is performed according to the procedure shown in (a) to (c). In these drawings, (a) is a diagram showing the entire configuration of the golf club, (b) is a diagram showing a state in which the shaft is partially cantilevered, and (c) is a reference point which is a fitting end of the head. It is a figure showing the state where load W was added.

First, the head H and the grip 101 are removed from the shaft 100. Next, as shown in (b), the cantilever is supported from the base end c of the shaft to the position a of 173 mm, and the fitting end H of the head H of the shaft 100 is
Let 1 be a reference point b. Then, as shown in (c), a load W is added at the reference point b, and the position is flexed by a predetermined amount. The load applied here is set so that the amount of deflection is 0.1 × R when the distance between a and b is R, and when the reference point b is bent by this amount, The angle between the tangent line at the reference point and the axis of the shaft in a cantilevered state is the deflection angle θ.

Alternatively, it is also effective to use a shaft having a small bending rigidity at the front end, in addition to the shaft having the above-mentioned deflection angle. That is, the average value of the bending stiffness from the neck end of the shaft (the position indicated by H1 in FIG. 4) to the grip side up to 100 mm or the bending stiffness at the 100 mm position is 4.0 × 10 ⁶ for the wood type club. Kgf · mm ² or less, preferably 3.
It is set to 5 × 10 ⁶ Kgf · mm ² or less, and is set to 4.5 × 10 ⁶ Kgf · mm ² or less, preferably 4.0 × 10 ⁶ Kgf · mm ² or less for an iron type club. Is good. By using a shaft having such rigidity characteristics, when hitting above the sweet spot position, it is possible to reduce the resistance when the head rotates in the direction to increase the loft, and as a result, the ball becomes more It is easy to climb and the flight distance can be improved.

The measurement of the sweet spot height in the iron club described above is performed, for example, by referring to FIGS. 5 (a) to 5 (c).
The procedure is as follows. The head 40 in which the position of the sweet spot S has been measured in advance is placed on the height measuring device 50 so as to have a predetermined lie angle (FIGS. (A) and (b)).
2 is pressed against the sweet spot S, and the height H in this state is measured. Accordingly, in the case of an iron type head as shown in the figure, as described above, the height H is the face center at the time of hitting the ball (the height of the center of gravity of the ball (about 21
mm), which is less than 18 mm, which is the preferred ball hit position of the face set from (mm).

As described above, by forming the head such that the center position of the sweet spot is on the heel side and the sole side with respect to the center position of the face or the center position of the pattern representing the hitting position, golf is performed. When the golf club swings, the area where the golf player is most conscious of catching the ball can be the position where the flight distance is the easiest and the directionality is stabilized. That is, by swinging naturally and making an impact, it is possible to easily catch the ball at a portion where the flight distance is most likely to appear.
Further, since the center position of the sweet spot is located near the axis of the shaft, toe-down is suppressed, impact can be achieved at a stable lie angle, and directionality can be stabilized. The present invention is particularly effective for a golf club equipped with a large head having a long distance in the toe-heel direction and a volume of 250 cc or more.

[0029]

According to the golf club equipped with the head of the present invention, the return of the head at the time of the swing can be effectively used to improve the flight distance of the ball, and the ball can have a high trajectory. It is possible to extend the flight distance. In addition, it is possible to prevent the generation of a low ball or a hook ball due to excessive return of the head, thereby improving the directional stability.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention,
2A is a diagram showing a wood type head, and FIG. 2B is a diagram showing an iron type head.

FIG. 2 is a diagram showing a second embodiment of the present invention;
(A) And (b) is a figure which shows the wood type head from which the pattern shape formed in a face surface respectively differs.

FIG. 3 is a diagram showing a distance from a center position of a face to a sweet spot.

FIG. 4 is a diagram including (a) to (c) and showing a procedure for measuring a deflection angle of a shaft.

FIGS. 5A to 5C are diagrams showing an example of a procedure for measuring the height of a sweet spot in an iron type head.

[Explanation of symbols]

 1,10,20,30,40 head 2,12,22,32 face

Claims (2)

[Claims] 1. A golf club having a head having a sweet spot center position in an area on a heel side of a center position of a face surface and in an area below the center position. 2. A head having a pattern on a face surface capable of recognizing a center position of a hit ball, wherein a sweet spot is provided in an area on the heel side of the center position of the pattern and below the center position of the pattern. A golf club having a head having a center position.