JP2005304775A - Golf club set - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a golf club set for which a golf ball catching degree and the good quality of the return of a face surface are matched. <P>SOLUTION: In the golf club set having a plurality of golf clubs for which the loft angles of golf club heads are different from each other, when a value obtained by multiplying the acceleration component of the golf club head in a direction orthogonal to a hitting direction on a surface in parallel with the ground surface immediately before a golfer hits a golf ball, the retreat amount of a centroid position which is a distance along the hitting direction from the center axis of the golf club shaft of the golf club or the extension of the center axis to the centroid position of the golf club head and the mass of the golf club head of the golf club is defined as the first index of the golf club, with the first index of the golf club whose loft angle is the maximum among the plurality of golf clubs as a reference, the first indexes of any golf clubs are in the range of 75% to 100%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a golf club set, and more particularly to a golf club set that supplies a plurality of golf clubs having different loft angles as a set.

A golfer uses a plurality of golf clubs having different counts or loft angles so that golf balls can fly freely at various distances. In general, a so-called degree of catching of a ball is known as one of the hitting characteristics of a golf club when hitting a golf ball. The degree of catch refers to the degree of lateral displacement of the face surface felt by the golfer at the moment of impact when the golfer holds the golf club and hits the golf ball.
As a golf swing, it is ideal to hit a golf ball with a square face at the moment of impact. However, in the case of a right-handed golfer, the golf club shaft twists clockwise in the backswing and, conversely, twists counterclockwise in the downswing. Therefore, even if the golfer puts the golf club head in a position where the golf ball can be hit with the face face in a square state, the face face is not impacted at the time of impact from the back swing to the down swing. It is not always a square state.
Generally, a golfer feels that the closer the face surface at impact is to a square state, the better the degree of catch. That is, it can be said that the degree of catch that the golfer feels corresponds to the good return of the club head where the face surface returns to a square state.

When a golfer hits a golf ball while holding a golf club, if the face surface is in an open state at the moment of impact, the golf ball is launched by slicing and turning to the right, and the flight distance does not increase. At this time, the golfer feels that the golf ball could not be caught in an accurate state (square state).
On the other hand, when a golfer hits a golf ball, if the face surface is in a square state at the moment of impact, the golf ball is hit straight and the flight distance increases. At this time, the golfer feels that the degree of catching was good, assuming that the golf ball could be caught with the face surface in an accurate state. In general, such a situation is said to have been a good return of the golf club head.
Such hitting is naturally affected by the swing of each golfer, but it also depends on the specifications of the golf club.

By the way, the degree of catch and the good return of the golf club head that the golfer feels about such a golf club are perceived sensuously only after the golfer actually hits the golf ball. Therefore, conventionally, it has not been sufficiently studied to quantitatively consider the degree of catch and the good return as the hitting characteristics of a golf club.
A technique related to the degree of catch and the good return is disclosed in Patent Document 1 below. Patent Document 1 discloses that the center of gravity formed between the face surface and the vertical surface of a golf club head in a state in which the golf club shaft is held horizontally while being rotatable about its central axis, and the rotation of the golf club shaft is stopped. A golf club having a corner set in a predetermined range is disclosed. It is described that when the barycentric angle is smaller than the predetermined angle, the golf ball easily rotates in slices, and when the barycentric angle is larger than the predetermined angle, the golf ball easily rotates by hook. (Column 5, 5th to 7th lines of Patent Document 1).
Japanese Patent No. 2645389

However, the barycentric angle referred to in Patent Document 1 is determined by the barycentric position that is the configuration of the golf club head, and is not an index to be evaluated based on the dynamic motion of the golf club head when the golf club is swung. .
Therefore, the barycentric angle is a constant evaluation result that does not include the head speed during golf swing, which varies with each golfer, and is sufficient as an index reflecting the degree of golf ball catching and the club head return that the golfer feels. It wasn't.
Therefore, since the degree of catch and the goodness of return cannot be quantitatively studied, the degree of catch of golf balls and golf between golf club sets having a plurality of golf clubs in a series or a plurality of golf clubs of iron sets. Some club heads vary in return. For example, although the capture degree of the golf ball in the golf club of 6 iron and the good return of the golf club head are good, the capture degree and return good in the 5 iron golf club are bad, and it is launched by slice rotation. As a result, the flight distance of a 5-iron golf club may not match the flight distance of No. 6.
In other words, although it is a golf club set and a golf club sold as a set, there is a variation in the degree of catch of the golf ball and the return of the club head among those golf clubs. If golf balls cannot be freely struck at various distances, golfers may be uneasy.
The present invention has been made in view of such problems, and in a golf club set having a plurality of golf clubs in a series and a plurality of golf clubs of an iron set, the degree of catching of the golf ball and the return of the golf club head An object is to provide a golf club set with good quality.

In order to solve the above problems, the present invention provides a golf club set having a plurality of golf clubs having different loft angles of golf club heads, on a plane parallel to the ground immediately before the golfer hits the golf ball. And an acceleration component of the golf club head in a direction perpendicular to the striking direction, and a distance along the striking direction from the center axis of the golf club shaft of the golf club or an extension of the center axis to the center of gravity position of the golf club head When the value obtained by multiplying the retraction amount of the center of gravity position and the mass of the golf club head of the golf club is the first index of the golf club, Based on the first index of the golf club having the maximum loft angle, the first index of any golf club is 75% to 1 To provide a golf club set, characterized in that it is in the range of 0%.
Furthermore, the present invention is preferably based on the first index of the iron club whose loft angle is between 40 degrees and 44 degrees. The golf club set preferably includes a plurality of different golf clubs having a golf club head loft angle in the range of 20 ° to 44 °.

Further, the present invention provides a golf club set having a plurality of golf clubs having different loft angles of golf club heads, on a plane parallel to the ground and perpendicular to the striking direction immediately before the golfer strikes the golf ball. The acceleration component of the golf club head in the direction of travel, and the retraction of the center of gravity position that is the distance along the striking direction from the center axis of the golf club shaft of the golf club or an extension line of the center axis to the center of gravity position of the golf club head When a value obtained by multiplying the amount and a twist angle that is an angle at which the center angle of the golf club shaft is twisted when a predetermined amount of torque is applied to the golf club shaft is used as the second index, Of the plurality of golf clubs, any golf club is determined based on the second index of the golf club having the maximum loft angle. To provide a golf club set which lies in the second range indicator from 80% to 120% of the drive.
Furthermore, the present invention is preferably based on the second index of the iron club whose loft angle is between 40 degrees and 44 degrees.
In the present invention, the acceleration component is a value obtained by subtracting 3 inches from the golf club length (inch) from the head speed value (m / s) immediately before hitting the golf ball when the golfer hits the golf ball. In the golf club head trajectory when the golfer hits the golf ball, the curvature radius immediately before hitting the golf ball on the projected trajectory projected onto the plane parallel to the ground is assumed to be a value calculated as 1300 mm. You can also.

According to the present invention, there is provided a golf club set having a plurality of golf clubs in which the first index or the second index indicating the degree of catch of the golf golf ball and the return of the golf club head is set within a predetermined range. can do.
Therefore, in a golf club set having a plurality of golf clubs in a series and a plurality of golf clubs of an iron set, it is possible to provide a golf club set in which the degree of catching of the golf ball and the good return of the golf club head are aligned. .
As a result, in a golf club set having a plurality of golf clubs in a series and a plurality of golf clubs of an iron set, the golfer is given a sense of confidence that the degree of catching of the golf ball and the return of the golf club head are uniform. Can do.

A golf club set according to the present invention will be described in detail based on an embodiment shown in the accompanying drawings.
FIG. 1 is a schematic diagram showing an example of a golf club set according to an embodiment of the present invention. The golf club set 10 is composed of 3 irons (A3) to 9 irons (A9), pitching wedges (AP), approach wedges (AA) and sand wedges (AS). Consists of. Each iron golf club has a grip 14 at one end of a golf club shaft 12 and a golf club head 16 at the other end, as indicated by an iron A6 in FIG. The golf club head 16 is connected to the golf club shaft 12 via a socket 20 on a hosel 18 projecting upward on the heel side.

Here, the count is mainly represented by numbers (natural numbers), letters, symbols, or the like given to the golf clubs so that golf clubs having different loft angles θ can be arranged in the order of the loft angles θ. The identification information regarding the order of the loft angle θ.
Further, the loft angle θ is an angle formed by the golf club shaft axis S and the face surface 22 as indicated by an iron A6 in FIG. 1, and is appropriately set by a person skilled in the art at a constant or substantially constant interval.

Here, when showing an example of the loft angle θ of each count, the loft angles θ of the irons A3 to AS are 21 ° for A3, 24 ° for A4, 27 ° for A5, 30 ° for A6, 34 ° for A7, A8 is 38 °, A9 is 42 °, AP is 47 °, AA is 52 °, and AS is 57 °. The loft angle θ increases as the number increases. Generally, in a golf club having a count of A3 to A9, a loft angle is in a range of 20 ° to 44 °, and in a golf club having a count of A9, a loft angle is in a range of 40 ° to 44 °.
The loft angle θ of these counts increases with a step size of 3 ° from A3 to A6, increases with a step size of 4 ° from A7 to A9, and increases with a step size of 5 ° from AP to AS. ing. The step size of the loft angle of the irons A3 to AS is not limited to this example, and may be a constant step size such as 3 ° or 4 °.
In golf club sets, generally, the length of the golf club shaft from the end of the grip to the lower end of the golf club head gradually decreases as the count increases. That is, the golf club shaft having a smaller count has a longer length and a smaller loft angle.

  Examples of the golf club set according to the present invention include ten iron golf club sets (A3 to AS) or iron golf club sets with numbers 3 to 9, but the golf club according to the present invention. The set includes not only an iron golf club set, but, for example, a wood golf club set, a golf club set in which the boundary between a wood golf club set and an iron golf club set is removed, only a golf club corresponding to a long iron, or a wood A golf club set composed of a plurality of golf clubs having different loft angles θ, such as a golf club set including a so-called utility golf club, which has an intermediate performance between a golf club and an iron golf club, and is difficult to classify both. Is included.

  In the present invention, in the golf club group in which the loft angle in the golf club set is in the range of 20 ° to 44 °, it is preferable that the golf ball catching degree and the golf club head return are good. This is because a golf club having a loft angle in the range of 20 ° to 44 ° is required to have a specific flight distance as described above, and when this flight distance is determined, This is because it is required that the degree of catching of the golf ball and the good return of the golf club head be aligned.

On the other hand, drivers with a loft angle θ of less than 20 ° and wedges with a loft angle θ of more than 44 ° are often purchased as a single item rather than as a component club of a golf club set. As you can see from the fact that they are actively sold as single items, golf clubs with a loft angle θ of less than 20 ° are mainly for teeing up and hitting balls to earn flight distance. However, it is not always required that the flight distance can be determined.
Furthermore, golf clubs with a loft angle θ greater than 44 ° are often used for controlled approach shots to control the swing force and ensure that the ball is placed on the green. Further, the shape of the sole portion or the contour shape of the face is mainly improved so that an approach shot can be easily performed, and it is not necessarily required that the flight distance is divided within the golf club set.
Therefore, the golf club set according to the present invention is a golf club set in which the golf ball having a loft angle in the range of 20 degrees to 44 degrees has the same degree of catching of the golf ball and good return of the golf club head. Is preferred.

Among the three golf clubs A3 to A9 shown in FIG. 1, the golf balls are captured on the basis of the moment M or the value T when the golfer grips the golf club and performs the golf swing. Good golf club head return.
Specifically, among the golf clubs having A3 to A9, the moment M of the other golf club is set in the range of 75% to 100% based on the moment M of the golf club of A9 having the maximum loft angle. Has been. Alternatively, among the golf clubs having A3 to A9, the values T of other golf clubs are set in the range of 80% to 120% with reference to the value T of the golf club of A9 having the maximum loft angle. .

FIGS. 2A to 2C are diagrams for explaining the moment M that each golf club has as a first index and the value T that the golf club has as a second index. The state immediately before hitting the golf ball 32 when performing golf swing (the moment of impact on the golf ball 32) is shown.
2A schematically shows the golfer from the upper side perpendicular to the ground, FIG. 2B schematically shows the golfer performing the golf swing from the rear, and FIG. 2C shows the head of the golf club 30. The enlarged view of a part is represented.

As shown in FIG. 2A, the path of the golf club head when the golfer G swings, that is, the path of the center of gravity A of the golf club head is a part of a circle with a radius of curvature R _s as indicated by a dotted line. expressed. The curvature radius R _s is a curvature radius R _s (hereinafter referred to as a golf ball hitting golf ball in a projected trajectory projected onto a plane parallel to the ground among the golf club head trajectories when a golfer hits a wolf ball. , Referred to as a curvature radius R _s of the golf club head).

As shown in FIG. 2, a golf club head that moves with a radius of curvature R _s immediately before the golf ball 32 is hit has a centrifugal force component F in a direction parallel to the ground on which golf swing is performed and in a direction perpendicular to the hitting direction. _x acts. The centrifugal force component F _x is calculated using the well-known formula for calculating the centrifugal force in the circular motion shown in the following formula (1), and the curvature radius R _s of the golf club head and the golf club head just before hitting the golf ball. It can be determined from the head speed H _s (hereinafter referred to as the head speed H _s ) and the mass W _h of the golf club head.
F _x = W _h × (H _s ² / R _s ) (1)
Here, the mass W _h of the golf club head is specific to each golf club head, and the curvature radius R _s of the golf club head depends on the length of the golf club shaft, the reach of each golfer, etc., and the head speed H _s basically corresponds to the swing speed of each golfer. A value obtained by dividing the square of the head speed H _{s by} the radius of curvature R _s of the golf club head (H _s ² / R _s ) is a surface parallel to the ground out of the acceleration of the golf club head immediately before hitting the golf ball. And an acceleration component in a direction orthogonal to the striking direction (hereinafter referred to as acceleration component (H _s ² / R _s )), and the centrifugal force component F _x is the acceleration component (H _s ² / R _s ) and the golf club head. It can be calculated by multiplying by the mass W _{h of} .

Further, the centrifugal force component F _x acting on the golf club head gives a moment M around the central axis of the golf club shaft. The moment M acting around the central axis of the golf club shaft is calculated by multiplying the centrifugal force component F _x and the retraction amount G _r of the center of gravity position A, which will be described later, as shown in the following formula (2). Can do.
M = _Fx * _Gr (2)
Here, as shown in FIG. 2C, the retraction amount _Gr of the gravity center position A is along the hitting direction from the central axis of the golf club shaft or an extension line of the central axis to the gravity center position A of the golf club head. Represents the distance. The moment M calculated by the above formulas (1) and (2) is a moment that causes torsional deformation around the central axis of the golf club shaft.

The retraction amount G _r is the distance G _r between the center of gravity A of the head 40 and the plane P that includes the shaft axis and is perpendicular to the flying ball direction F in the plan view of the head of the golf club shown in FIG. is there. FIG. 5 is a side view of the golf club head as seen from the toe side. Similarly, the distance _Gr is the center of gravity retreat amount.
More specifically, with the head installed on a horizontal plane according to the lie angle and with its face surface facing the flying ball direction, the head's center of gravity and the front surface including the shaft axis and perpendicular to the flying ball direction And the distance.
Here, installation according to the lie angle is a state in which the gap between the round of the sole surface of the head and the flat installation surface is substantially equal on the toe side and the heel side. When the round of the sole surface is unclear, the score line and the installation surface are installed in a parallel state. When the round of the sole surface is unclear and the score line is not linear, for example, when the parallel to the installation surface cannot be determined, the lie angle (degree) = (97−club length (inch)) is set. For example, if the club length is 38 inches, the lie angle is 97−38 = 59 degrees.

The club length is measured by the measuring method established by the Japan Golf Association. An example of the measuring device is Club Major II manufactured by Kamoshita Seikosho Co., Ltd. That is, as shown in FIGS. 6 and 7, when the heel end is the starting point P1 and the grip end is the end point P2, the distance C between these P1 and P2 is the club length.
As shown in FIG. 8, the center-of-gravity retraction amount _Gr is measured by a seesaw-type balance 41 that can swing in the direction of arrow U about the fulcrum 42. The balance 41 has a shaft pin 43 having a fit with no gap with respect to the hosel hole of the head, and is balanced so that the arm 44 is horizontal when the head or weight is not attached.
Measurement of distance G _r from the shaft axis of the center of gravity of the head A, as shown in FIG. 9, the distance G _r is the arm longitudinal direction showing the head 40 of the mass W to the shaft pin 43 and FIGS. 4 and 5 mounted The head 40 shown in FIG. 6 is fixed while being rotated along the plane P so that the head 40 shown in FIG. 6 can be mounted on the shaft pin 43 extending in the vertical direction shown in FIG. . Then, a weight body 45 having a mass W ′ such that the arms 44 are balanced horizontally and a length L ′ from the center of gravity A ′ to the fulcrum of the weight body 45 are selected.

As described above, the retraction amount of the center of gravity (distance G _r ) from the shaft axis can be obtained from the balance formula W × G _r = W ′ × L ′ by G _r = (W ′ × L ′) / W. In the side view of the balance 41 shown in FIG. 9, the face surface 46 is slightly visible because the head 40 has a loft angle and a lie angle. The above explanation is the principle of measuring the amount of retraction of the center of gravity from the shaft, and the measuring instrument includes a center of gravity measuring instrument manufactured by Kamoshita Seikosho Co., Ltd.

  Further, the torsional deformation of the golf club 30 with the golf club shaft as the central axis depends on the torsional strength of the golf club shaft in addition to the moment M described above. This torsional strength is expressed by an angle of a central angle (hereinafter referred to as a torsion angle X) that is twisted when one end of the golf club shaft is fixed and a constant torque is applied to the free end. That is, the larger the twist angle X, the softer the golf club shaft, and the smaller the twist angle X, the harder the golf club shaft. In the present embodiment, a value T is a value obtained by multiplying the above-described moment M by the twist angle X.

Therefore, when the moment M or the value T increases, the torsional deformation of the golf club 30 with the golf club shaft as the central axis increases, and the orientation of the face surface immediately before the golfer hits the golf ball 32 is likely to change.
Here, the direction of the face surface refers to the direction of the ball striking surface of the golf club head, and particularly to the left and right (toe side, heel side). That is, it refers to the direction in which the face surface opens or closes when viewed from the golfer.

In the golf swing, the golf swing performs the golf swing so that the orientation of the face surface returns to the orientation of the face surface set in the address state during the impact from the top state. However, the moment M acts on the golf club 30 to cause torsional deformation on the golf club shaft, thereby changing the orientation of the face surface. Therefore, even if the golfer performs a golf swing such that the face surface at the time of impact returns to the orientation of the face surface set in the address state, the orientation of the face surface in the state where the face surface is in the address state is not necessarily limited by torsional deformation. It does not always return to the direction.
In the present invention, the inventors of the present application have found a correspondence relationship between such moment M or value T and the return of the face surface felt by the golfer, and have provided the above-described golf club.

Hereinafter, the relationship between the moment M or the value T and the return of the face surface felt by the golfer will be described. In the golf club set relating to the return of the face surface that each golfer feels from the hit feeling, having 10 golfers (G _a to G _j ) actually try the 13 types of golf club sets shown in Table 1 to Table 13 I was asked to evaluate the difference.
The golf club set used for the test hit here is a set of seven iron golf clubs with counts from 3 to 9, and AP, AA, and AS spin golf balls near the cup. Since it is used for approach shots such as approaching and does not adjust the flight distance of the golf ball, it is excluded from the evaluation regarding the return of the face surface.

In the evaluation method, an iron golf club is tried for each golf club set (A to L), and the degree of return of the face surface within the golf club set varies greatly (evaluation point 2), and there is a slight difference ( Evaluation was made in three stages: evaluation point 1) and no difference (evaluation point 0). And the average value of the evaluation score evaluated by 10 golfers (G _a to G _j ) was calculated.
Therefore, the golf club set evaluated by all 10 golfers as having an evaluation score of 2 has an average value of 2 and can be evaluated as having a large difference in the degree of return of the face surface in the golf club set. . On the other hand, the golf club set evaluated by all 10 golfers as having an evaluation score of 0 has a mean value of 0, and there is no difference in the degree of return of the face surface in the golf club set. It can be evaluated that there is.

Tables 1 to 6 show characteristic values (club name, count, golf club length, head mass W _h , retraction amount G _{r of the} center of gravity position A) of each of the six types of iron golf club sets (A to F). , Moment M, and ratio). Here, the ratio is a value that represents the moment M of each golf club with reference to the moment M of the golf club of No. 9 as a reference (1.00), that is, the moment M of each golf club is the value of the golf club of No. 9 The value divided by the moment M. The golf club No. 9 having the maximum loft angle is a golf club whose loft angle is set in the range of 40 ° to 44 °.
The moment M, as will be described later, is a value obtained by subtracting 3 inches from the golf club shaft length (inch) from the curvature radius R _s of the golf club head of 1300 mm and the head speed H _s (m / s) of the golf club. It can be considered and is calculated from the equations (1) and (2) using this.
Further, Table 14 shows the results of evaluation by 10 golfers (G _a to G _j ) regarding the return of the face surfaces in the six golf club sets (A to F).

Tables 7 to 13 also show the characteristic values (club name, count, golf club length, head mass W _h , head position of the center of gravity) of each of the other six types of iron golf club sets (G to M). Quantity G _r , moment M, value T, and ratio).
The torsion angle X refers to the angle of the center angle at which one end of the golf club shaft is fixed and a constant torque is applied to the free end, and represents the torsional rigidity of the golf club shaft. That is, the larger the twist angle X, the softer the golf club shaft, and the smaller the twist angle X, the harder the golf club shaft. The torque applied at this time is 13.5 (kgf · cm). In addition, this ratio represents the value T of each golf club with the value T of the ninth golf club as a reference (1.00). This value T is a value obtained by multiplying the moment M by the twist angle X.
Table 15 shows the results of evaluation by 10 golf players (G _a to G _j ) regarding the return of the face surfaces in the six golf club sets (G to M).

From the evaluation results shown in Table 14, the average values of the golf club sets A and B are 0.3 and 0.2, and the average value of the golf club sets A and B is 0 as compared with the other golf club sets. Close to. That is, the golf club sets A and B are golf club sets in which the difference in the return of the face surface that the golfer feels from the hit feeling is small.
Further, referring to Tables 1 to 6, the ratio of the golf clubs is in the range of 0.75 to 1.00.
Therefore, a golf club set in which the moment M is set from 75% to 100% with reference to the iron golf club of No. 9 is a golf club set in which the goodness of the return of the face surface between the counts is aligned. Can be evaluated by golfers.

Therefore, in order to provide a golf club set with less uncomfortable feeling within the golf club set with respect to the return of the face surface, the ratio of the moment M is in the range of 0.75 to 1.00 with respect to the golf club with the number 9 If it is in.
Further, as described above, this ratio is a value that represents the moment M of each golf club with the moment M of the golf club No. 9 as a reference (1.00). Can evaluate goodness.

From the evaluation results shown in Table 15, the average values of the golf club sets G, H, and M are both 0.3, and the average values of the golf club sets G, H, and M are compared with the other golf club sets. Is close to zero. That is, the golf club sets G, H, and M are golf club sets that have a small difference in face surface return feeling that a golfer feels from the hit feeling.
When the ratio of each golf club is seen with reference to Table 7 to Table 13, the ratio of the values T of the golf club sets G and H is in the range of 0.80 to 1.00.

Further, referring to Table 12 (golf club set L), the ratio of the value T is different from the ratio of the moment M, and the number 9 golf club is not the maximum. In other words, the moment M tends to increase as the count increases. Yes, the number 9 golf club is the largest, but the value T does not increase as the number increases as in the golf club set L shown in Table 12.
The moment M tends to increase as the count increases, but the twist angle X tends to decrease as the count increases because there is a portion that depends on the length of the golf club shaft, and the value T is equal to the moment M and the twist. This is considered to be a value obtained by multiplying the angle X.
Therefore, referring to Table 15, the average value of the golf club set L is 0.6, and it is difficult to say that the difference in the degree of return of the face surface in the golf club set is small. Since the range of .00 to 1.21 is set, the golf club set in which the ratio of the value T is in the range of 1.00 to 1.21 is a golf club set in which the goodness of the face surface is not uniform. Can be evaluated. From this, it can be said that the golf club set in which the ratio of the value T is in the range of 1.00 to 1.20 is also a golf club set with a small difference in returnability of the face surface.
Therefore, a golf club set in which the value T is set from 80% to 120% with reference to the iron golf club of No. 9 is a golf club set in which the goodness of the return of the face surface between the counts is aligned. Can be evaluated by

In order to provide a golf club set with less discomfort within the golf club set regarding the return of the face surface, the ratio of the value T should be within the range of 0.80 to 1.20 based on the golf club with the number 9 That's fine.
Further, since this ratio is a value representing the value T of each golf club with the value T of the golf club No. 9 as the reference (1.00), the return of the face surface can be evaluated using the value T as an index.

As described above, in the present embodiment, the golf club moment M or value T is set within a predetermined range according to the equations (1) and (2), but the acceleration component (H) used in the equations (1) and (2) is used. _s ² / R _s ), or the curvature radius R _s and the head speed H _s of the golf club head are not particularly limited, and an average value or the like of values obtained by measuring actual swing may be used, or a substitute value is used. May be.

By the way, the inventors of the present application found a certain relationship from the measurement results shown in Table 16 and FIG. 3 regarding the curvature radius R _s and head speed H _s of the golf club head used when setting the moment M or the value T. ing.

Table 16 shows the head speed H _s immediately before hitting the golf ball when five golfers (G _a to G _e ) swing the golf clubs 3 to 9 using the swing measurement system. the results obtained by measuring the radius of curvature R _s of the golf club head, FIG. 3 is a scatter diagram showing the relationship between (from G _a G _j) golfer and length of the head speed H _s and the golf club shaft according to Table 16 is there.

As shown in FIG. 3, the head speed H _s and the length of the golf club shaft of the golf club head, linear approximation (both correlation coefficients 0.98 or more).
Further, referring to Table 16, the head speed H _s immediately before striking the golf ball _(m / s), when the golfer G _a is 3 inches subtracted from the length of the golf club shaft, expressed in inches substantially coincides with the value, substantially coincident with the value for 5 inches subtracted from the length of the golf club shaft, expressed in inches in the case of golfer G _b, golf, expressed in inches in the case of golfer G _d It approximately matches the length of the club shaft.
Standing teeth, by utilizing the fact that the head speed H _s and the length of the golf club shaft is in a linear relationship, the length of the golf club shaft, expressed in inches from (inches), obtained by subtracting a predetermined value value Can be used as a substitute value for the head speed H _s (m / s).
Since nearest to the standard level swing speed of the general golfer a golfer G _a, standard head speed H _{s (m} / s) the 3-inch subtracted value from the length of the golf club shaft (inch) Can be considered.

On the other hand, referring to Table 16, the curvature radius R _s of the golf club head is substantially constant irrespective of the head speed H _{s of} each golfer and the golf club number, so the curvature radius R _s of the golf club head is It can be regarded as 1300 mm.

Accordingly, a value obtained by subtracting 3 inches from the length of the golf club shaft expressed in inches is used as a head speed H _s and a value obtained by substituting 1300 mm as a curvature radius R _s , and a moment M or a value T is set within a predetermined range. Can be set to
However, a value obtained by measuring an actual swing with respect to the curvature radius R _s and the head speed H _{s of} the golf club head or the acceleration component (H _s ² / R _s ) used when setting the moment M or the value T within a predetermined range. May be used, or other substitute values may be used.

As a method of actually measuring the curvature radius R _s of the golf club head, for example, a swing analysis method using a three-dimensional magnetic sensor disclosed in Japanese Patent Application Laid-Open No. 2001-112903 by the applicant of the present application, or on the ground on which golf swing is performed. On the other hand, there is a method in which a high-speed camera is installed vertically upward, a golf club head trajectory is photographed, the position coordinates of the golf club are obtained by image processing, and the result is used.
Further, as a method of measuring the head speed H _s of the golf club head, for example, a method of calculating by determining a time difference of a golf club head across the two beams emitted from the light source.

Further, without using the curvature radius R _s and the head speed H _s of the golf club head, the acceleration of the golf club head immediately before hitting the golf ball is on the plane parallel to the ground and perpendicular to the hitting direction. The moment M or the value T may be set using the acceleration component (H _s ² / R _s ). That is, the acceleration component (H _s ² / R _s ) actually measured is multiplied by the golf club head mass W _h and the retraction amount G _{r of the} center of gravity to obtain a moment M, and further multiplied by the twist angle X. The value T may be used.
As a method of actually measuring such an acceleration component (H _s ² / R _s ), an acceleration sensor for measuring the acceleration in the central axis direction of the golf club shaft is attached to the golf club head, and the acceleration during golf swing is measured. There is a method of obtaining an acceleration component parallel to the ground from the measurement result.

Also, depending on the respective head speed H _s, by aligning moment M or the value T of each golf club in the golf club set to a predetermined range, the merit of the return of the golf club head is a predetermined in accordance with the swing speed The golf club set that is aligned with the range can be classified and provided according to the swing speed of each golfer.
For example, fast swing speeds, standard, and classified into low speed 3 stage, fast to swing speed by using a head speed H _s which corresponds to the moment M or the value T a golf club set that is set to a predetermined range of high-speed level golfer Can be classified as a golf club set.
Further, it is possible to have the golfer swing the golf club, recognize which speed level the head speed is, and provide a golf club set corresponding to the speed level.

  Further, the moment M or the value T described above may be displayed on a recording medium using display means such as letters, numbers, or symbols as an index for evaluating the degree of catch and the ease of returning the face surface. That is, the golf club set designed based on the moment M or the value T, which is an index for evaluating the degree of catch and the return of the face surface, can be recognized by the user via the recording medium. Such information may be provided to the user as a golf club set. Examples of such a recording medium include tags and stickers such as price tags and product tags, catalogs, and the like.

In the present invention, it is possible to provide a golf club set having a plurality of golf clubs in which the moment M or the value T is set in a predetermined range as an index indicating the degree of catching of the golf ball or the return of the golf club head.
Therefore, in a golf club set having a plurality of golf clubs in a series and a plurality of golf clubs of an iron set, it is possible to provide a golf club set in which the degree of catching of the golf ball and the good return of the golf club head are aligned. .
Further, by matching the moment M or value T of each golf club in the golf club set within a predetermined range according to the swing speed of each golfer, the return of the golf club head according to the swing speed is within a predetermined range. It is also possible to provide a golf club set arranged in accordance with the swing speed of each golfer.
Further, a value obtained by subtracting a predetermined value corresponding to the swing speed from the length of the golf club shaft expressed in inches is regarded as a head speed H _s (m / s) corresponding to each swing speed, and 1300 mm is golfed. The moment M or the value T can be set within a predetermined range by regarding the curvature radius R _s of the club head.
The golf club set according to the present invention has been described in detail above. However, the present invention is not limited to the above embodiment, and various improvements and modifications are made without departing from the gist of the present invention. Of course it is also good.

It is a mimetic diagram showing an example of a golf club set concerning an embodiment of the present invention. (A)-(c) is a figure which shows the state immediately before hitting the golf ball at the time of a golfer holding a golf club and performing a golf swing. It is a scatter diagram which shows an example of the relationship between head speed and golf club shaft length. It is a figure for demonstrating the retraction amount of a gravity center position. It is a figure for demonstrating the retraction amount of a gravity center position. It is a figure for demonstrating a golf club length. It is a figure for demonstrating a golf club length. It is a figure for demonstrating the measuring method of the retraction amount of a gravity center position. It is a figure for demonstrating the measuring method of the retraction amount of a gravity center position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Golf club set 12 Golf club shaft 14 Grip 16 Golf club head 18 Hosel 20 Socket 22 Face surface 30 Golf club 32 Golf ball

Claims (7)

In a golf club set having a plurality of golf clubs having different loft angles of golf club heads,
The acceleration component of the golf club head in a direction parallel to the ground and perpendicular to the striking direction immediately before the golfer hits the golf ball, and the central axis of the golf club shaft or the extension of the central axis of the golf club A value obtained by multiplying the retraction amount of the center of gravity position, which is the distance along the striking direction from the line to the center of gravity position of the golf club head, and the mass of the golf club head of the golf club, When the index is 1,
Of the plurality of golf clubs, the first index of any golf club is in the range of 75% to 100% based on the first index of the golf club having the maximum loft angle. Golf club set.   The golf club set having a plurality of iron club sets having different loft angles, wherein the loft angle is between 40 degrees and 44 degrees, and the first index of the iron club is used as a reference. Golf club set. In a golf club set having a plurality of different golf clubs with a loft angle of the golf club head in the range of 20 ° to 44 °,
The acceleration component of the golf club head in a direction parallel to the ground and perpendicular to the striking direction immediately before the golfer hits the golf ball, and the central axis of the golf club shaft or the extension of the central axis of the golf club A value obtained by multiplying the retraction amount of the center of gravity position, which is the distance along the striking direction from the line to the center of gravity position of the golf club head, and the mass of the golf club head of the golf club, When the index is 1,
Of the plurality of golf clubs, the first index of any golf club is in the range of 75% to 100% based on the first index of the golf club having the maximum loft angle. Golf club set. In a golf club set having a plurality of golf clubs having different loft angles of golf club heads,
The acceleration component of the golf club head in a direction parallel to the ground and perpendicular to the striking direction immediately before the golfer hits the golf ball, and the central axis of the golf club shaft or the extension of the central axis of the golf club An angle at which the center angle of the golf club shaft twists when a predetermined amount of torque is applied to the golf club shaft, and a retraction amount of the center of gravity position that is a distance along the striking direction from the line to the center of gravity position of the golf club head When the value obtained by multiplying the torsion angle that is is the second index,
Of the plurality of golf clubs, the second index of any golf club is in the range of 80% to 120% based on the second index of the golf club having the maximum loft angle. Golf club set.   5. The golf club set having a plurality of iron club sets having different loft angles, wherein the loft angle is between 40 degrees and 44 degrees, and the second index of the iron club is used as a reference. Golf club set. In a golf club set having a plurality of different golf clubs with a loft angle of the golf club head in the range of 20 ° to 44 °,
The acceleration component of the golf club head in a direction parallel to the ground and perpendicular to the striking direction immediately before the golfer hits the golf ball, and the central axis of the golf club shaft or the extension of the central axis of the golf club An angle at which the center angle of the golf club shaft twists when a predetermined amount of torque is applied to the golf club shaft, and a retraction amount of the center of gravity position that is a distance along the striking direction from the line to the center of gravity position of the golf club head When the value obtained by multiplying the torsion angle that is is the second index,
Of the plurality of golf clubs, the second index of any golf club is in the range of 80% to 120% based on the second index of the golf club having the maximum loft angle. Golf club set. The acceleration component is a value obtained by subtracting 3 inches from the length (inches) of the golf club, the value (m / s) of the head speed immediately before hitting the golf ball when the golfer hits the golf ball,
The golf club head trajectory when a golfer hits a golf ball is a value calculated by setting a curvature radius immediately before hitting the golf ball in a projected trajectory projected onto a plane parallel to the ground as 1300 mm. The golf club set according to any one of 1 to 6.

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