JP2001190711A - Set of iron clubs - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a set of iron clubs in which the deformation of a shaft while swinging is set to have almost the same characteristics among the numbered clubs in the set. SOLUTION: Each numbered iron club in the set is adjusted in flexural deformation and torsional deformation of a shaft at least at the time of 'take away' and 'impact' while swinging a club. Especially the difference of such deformation among the numbered clubs is controlled to be less than about 20%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to setting of shaft characteristics of each iron number in an iron club set.

[0002]

2. Description of the Related Art In a golf club set including various iron counts such as a long iron, a middle iron, and a short iron, a club shaft has generally been a series of irons depending on flex or frequency. Is being done.

[0003] Flex is an index indicating the ease of bending of the shaft, and is indicated by "X, S, R, A, L" from the hard side, and a fulcrum is placed at 12 inches from the grip end to set the shaft. The weight of the head is measured by lowering the weight to the tip and measuring the weight of the weight until the tip of the head has a certain amount of drooping.The vibration frequency is based on the natural frequency of the shaft as an index. The weight, the length of the shaft, the material and shape of the shaft, and the like can be calculated by using a known mathematical expression (numerical expression omitted) as a parameter.

Conventionally, these values are harmonized between the counts in the set (for example, the same value is set for each count in the set, or the count is set for each count or a group of a plurality of counts). The value was changed regularly.) Was the best set. For example, in the case of an iron club set, it is 9 from the second iron to the pitching wedge.
A set in which the clubs of all the counts are made easy to bend the R-flex, and the frequency is linearly increased from 298 cpm to 331 cpm to be harmonized, or a set in which the value of the flex is changed by a fixed amount for each count, etc. Has been proposed.

[0005]

However, in the above-described conventional harmonizing method, the deformation of the shaft when the club is actually swung is not taken into account, and it is based on static measurement values and specifications. Because of this, there are actually several clubs in the set that do not fit the golfer's swing sensation in the short iron and the long iron because the bending of the shaft during the swing is much larger than necessary. Often results.

For example, in the case of a long iron in which the shaft is long and the flight distance is emphasized, in order to obtain the ease of swing, compared to a normal short iron, a long iron is used.
Shafts with soft and easy-to-bend characteristics are used. However, in a set according to the conventional harmonizing method, a long iron and a short iron are used because they are excessively focused only on the ease of hitting with a long iron (easiness of swinging). -There is a tendency that the difference in bendability between the iron and the iron is set too large.

For this reason, there is a large difference in swing feeling between each count in the set. In particular, when the ease of bending of a long iron is set to be excessive, the address is set at a right angle to the target direction. After the face surface is once opened by the swing, it cannot return to the original state at the time of impact and is hit with the face surface open and the ball is launched to the right (in the case of right-handed, the same applies hereinafter). Becomes Therefore, in view of the above circumstances, an object of the present invention is to provide an iron club set in which the deformation of the shaft during the swing is set to have substantially the same characteristics at each count in the set. is there.

[0008]

In order to achieve the above object, an iron club set according to the present invention includes a long iron, a middle iron,
An iron club set including a plurality of iron clubs extending over a short iron, wherein at least at the time of turning back and impact during a club swing operation, the club number between the club number of the size of the "flexure" and the "bend" of the shaft. The difference is suppressed to approximately 20% or less.

[0009] A club swing operation at the time of hitting a golf ball with a golf club is performed by first taking an address posture in which the face of the head is opposed to a ball placed on the ground or teed up so as to hold the club. The head is swung up above the golfer's head and then swung down to speed up the head and hit (impact) the ball on the face surface.

[0010] At this time, the quality of the golfer's swing sensation depends on the "turning back" in which the above-mentioned swinging operation is performed to convert the club head swung up overhead into a downward swinging motion. It has been empirically found that the golfer feels from the club or shaft at two points: time and when the ball is impacted on the face.

The inventor of the present invention focused on the fact that the sensation received from the shaft was mainly derived from the bending deformation of the shaft during the swing, and in order to grasp the deformation state of the shaft during the club swing, the grip side was used. A pair of strain gauges are attached to two places at 90 degrees apart from each other in the shaft axis direction on the shaft surface of the shaft, and the "bend" of the shaft in the hit ball flight direction and the "flexure" in the toe down direction are measured, and their characteristics are measured. Considerations were made. The toe-down refers to a state in which, when the club head is swung down during a club swing, the tip of the shaft and the toe portion of the head hang down from the axis of the shaft toward the ground due to the centrifugal force of the head. Also, the toe-down direction is
This toe-down indicates the direction in which the toe portion of the head hangs down (see FIG. 1).

Thus, in the iron club set according to the present invention, the amount of "bend" and "bend" of the shaft at least at both the "turning back" and the "impact" during the club swing operation is determined in the following manner. As described in the example, the values are set so as not to be far apart between the club numbers in the set. As a result, the golf player can obtain the same swing sensation during the swing even if he hits with any iron club in the set, and the face opening with the long iron, which is a problem with the conventional product, can be obtained. Since the feeling of anxiety that it is difficult to return to is eliminated, a good swing can be performed with confidence.

If the difference between the numbers of the "flexures" or "bends" in the first invention exceeds 20%,
The shaft deformation of the long iron side club in the set becomes excessively large, and there is a great possibility that the above-mentioned inconsistency in swing sensation and uneasiness may occur in the conventional product. In addition, in order to easily obtain a shaft characteristic such as easy swinging with a long iron having a long shaft and accurate directionality of a hit ball with a short iron, the size of the above-mentioned “bending” and “bending” is required. It is not preferable to set the value of the difference between the counts to almost zero, and it is preferable to keep the lower limit of the value at about 5%. Therefore, the aforementioned "deflection"
And the difference between the numbers of "bends" are 10 to 1
It is good to set it to 8%, most preferably between 15 and 18%.

Also, in the present invention, the difference between the "flexure" and the "bend" of the shaft between the club counts is determined by shortening the "flexure" or "bend" of the shaft of the long iron side club. Ratio (%) divided by the size of the "flexure" or "bend" of the shaft of the iron side club
And a value obtained by subtracting 100 from.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment according to the present invention will be described below. In the present embodiment, a titanium alloy is used for the face surface of the head, stainless steel is used for the other head part, and a carbon shaft is used for the shaft. Seven pieces from 3 to 9 iron and a pitting wedge (PW) An iron club set including a total of eight clubs according to the present invention.

In this embodiment, the shaft characteristics of each count in the set are grouped by adjusting the shaft deformation during the swing, that is, the above-mentioned "flexure" and "bend". For this reason, first, the amount of "flexure" of the shaft in the toe-down direction of each club in the set is adjusted as follows. The “flexure” in the toe-down direction of the shaft is a moment M which is a product F × r of the centrifugal force F generated in the head during the swing and the distance r from the shaft axis to the center of gravity of the head (generally referred to as the center of gravity distance).
(See FIG. 1).

Here, the design factor of the club is adjusted so that the difference in the amount of "deflection" between the short iron and the long iron is reduced. In this embodiment, focusing on the distance r from the shaft axis to the center of gravity of the head, the difference in the size of the distance r between the long iron side club and the short iron side club is set as small as possible. Specifically, the center of gravity distance r of the club on the long iron side is smaller than that of the conventional product, and the center of gravity distance r of the club on the short iron side is larger than that of the conventional product based on the appropriately selected set of conventional products. Correction is set.

For this reason, in the present embodiment, the clubs on the long iron side (No. 3 to 5) are made approximately 3 mm longer than the clubs of the conventional set based on the hosel length, and at the same time, the heel The head weight on the side is set heavier than the conventional club. On the other hand, in each club on the short iron side (8 to PW), the hosel length is shortened by about 5 mm as compared with the conventional club, and at the same time,
The toe side head weight has been increased.

As described above, in this embodiment, the value of the center-of-gravity distance r is set to the value shown in the table of FIG. still,
As a comparative example, the center-of-gravity distance r of each iron number in the appropriately selected conventional iron set is simultaneously described. In a conventional iron set, the center of gravity of a long iron is set to be extremely longer than that of a short iron (for example, the center of gravity of a PW is 41.8 mm while the center of gravity of a PW is 41.8 mm). .

As a result, in this embodiment, the difference between the long iron and the short iron in the "flexure" of the shaft in the toe-down direction is much smaller than that in the comparative example. Further, in the comparative example, in a long iron, the toe-down amount at the time of the shaft swing is large, and the "flexure" of the shaft has an extremely large value.

Next, the setting of the amount of "bending" of the shaft for each club in the set of the present embodiment is performed as follows. That is, in order to reduce the difference in the amount of “bending” between the clubs on the long iron side and the short iron side, the “bending” of the long iron side clubs (No. 3 to 5) is reduced. The rigidity of the shaft in the club on the iron side is increased. As means for increasing the shaft rigidity, increasing the outer diameter of the shaft,
It is possible to increase the thickness of the shaft, increase the elastic modulus of the carbon fiber of the shaft material, or the like. In this embodiment, the outer diameter of the shaft is 1 mm at the tip (the so-called tip side).
The rear end (grip side) is enlarged by 2 mm.

As a result, as shown in the table of FIG. 3, the flex value of each number in the set is considerably higher than that of the set of the conventional product as a comparative example, particularly on the long iron side (No. 3). , About 2 kgf (19.6 N higher). Therefore, in the set of the present embodiment, particularly, the "bend" of the club on the long iron side is significantly reduced, and the difference in the "bend" between the club on the long iron side and the club on the short iron side is reduced. I have.

As described above, in the iron club set of this embodiment, the deformation of the shaft at the time of club swing, that is, "bending" and "bending" are suppressed particularly in the club on the long iron side. As shown, the difference in the magnitude of these deformations between the club on the short iron side and the club on the short iron side is extremely small and reduced, so that when swinging with the same force, almost the same swing feeling is felt for any club in the set. Can be obtained. In addition, since the shaft deformation of the long iron is suppressed to a small value during the swing, the face once opened at the time of the swing, which was a problem with the conventional long iron, cannot return to the original at the time of the impact and the hit ball jumps out to the right (right In the case of striking), the feeling of anxiety that this will happen is eliminated.

Further, as shown in FIG. 4 and FIG. 5 (shaft deformation of the conventional product), the "turn back" and the "impact", which most affect the golfer's swing sensation, are long. The difference between the "flexure" and "bend" of the shaft between the iron (No. 3) and the short iron (PW) (percentage minus 100, which is the amount of deformation of the long iron divided by the amount of deformation of the short iron) is a comparative example. Each of the conventional products has a large value of approximately 40%, whereas the embodiment has extremely small values of "flexure" of 15% and "bend" of 18%. A swing feeling can be obtained.

[0025]

In the iron club set according to the present invention, at least at both the "turning back" and the "impact" during the club swing operation, the club number between the "bend" and the "bend" of the shaft is required. Is less than about 20%, so that the golf player can hit any iron club in the set,
When the same swing feeling can be obtained during the swing, and if the opening of the face surface does not return to the original at the time of impact with a long iron which is a problem with the conventional product, the hit ball jumps to the right (in the case of right-handed) The feeling of anxiety is eliminated, and a good swing can be performed with confidence.

[Brief description of the drawings]

FIG. 1 is a view for explaining “deflection” deformation.

FIG. 2 is a diagram comparing a center of gravity distance between an example and a comparative example.

FIG. 3 is a diagram comparing flex values of an example and a comparative example.

FIG. 4 is a diagram showing a deformation of the shaft of the embodiment.

FIG. 5 is a diagram showing a deformation of a shaft of a comparative example (conventional product).

Claims (1)

[Claims] 1. An iron club set comprising a plurality of iron clubs ranging from a long iron, a middle iron, and a short iron, wherein at least at the time of turning back and at the time of impact during a club swing operation, the "flexure" of the shaft is determined. Is
An iron club set characterized in that the difference between the club numbers of the sizes of the clubs is suppressed to approximately 20% or less.