JP5936301B2 - Iron golf club set - Google Patents

Description

  The present invention relates to an iron golf club set having a plurality of iron-type golf clubs.

  An iron golf club set having a plurality of iron type golf clubs is commercially available. Normally, this club set includes a plurality of clubs having different real loft angles, lie angles, and lengths. Each club in the set is distinguished by an iron number. Based on various viewpoints, the head specifications are determined for each count.

  In Japanese Utility Model Publication No. 7-49970, the long iron club side is formed with the sole width gradually increasing as the count decreases, and the sole width on the short iron side is increased with the 5th iron or 6th iron as a boundary. The iron golf club set formed so that the sole width is gradually increased as it goes is disclosed.

No. 7-49970

  The present inventor has examined the optimization of the sole width in the iron set from a viewpoint different from the prior art. As a result, the present inventors have invented a sole width specification that can produce an effect different from that of the prior art.

  An object of the present invention is to provide a golf club set capable of appropriately exhibiting functions required for each count.

  The club set according to the present invention includes n (n is an integer of 2 or more) iron golf clubs. The toe side sole width d1 of these clubs is d1 (1), d1 (2),..., D1 (n) in order from the club with the smallest real loft angle L1, and the maximum of these toe side sole widths d1. The value is d1max, the minimum value of the toe side sole width d1 is d1min, and the heel side sole width d2 of these clubs is d2 (1), d2 ( 2),..., D2 (n), the maximum value of these heel side sole widths d2 is d2max, and the minimum value of these heel side sole widths d2 is d2min. The bounce angle θ1 is set to θ1 (1), θ1 (2),..., Θ1 (n) in order from the club having the smallest real loft angle L1, the maximum value of these bounce angles θ1 is θ1max, and this The minimum value of the bounce angle θ1 is set to θ1min. At this time, this club set satisfies θ1 (1) ≦ θ1 (2) ≦ ... ≦ θ1 (n), the d1max and the d1min are substantially the same, and the d2max and the d2min are the same. Are substantially the same.

  Preferably, the difference (d1max−d1min) is 1.0 mm or less. Preferably, the difference (d2max−d2min) is 1.0 mm or less.

  In a preferred embodiment, this club set satisfies d1 (1) ≦ d1 (2) ≦... ≦ d1 (n) and d2 (1) ≦ d2 (2) ≦. n) is satisfied.

  In another preferred embodiment, the club set satisfies d1 (1) ≧ d1 (2) ≧...> D1 (n) and d2 (1) ≧ d2 (2) ≧. d2 (n) is satisfied.

  Preferably, the difference (d1max−d1min) is 0.8 mm or less. Preferably, the difference (d2max−d2min) is 0.8 mm or less.

  This iron golf club set can appropriately exhibit the functions required for each count.

FIG. 1 is a view showing a golf club set according to an embodiment of the present invention. FIG. 2 is a perspective view of a head used in the set of FIG. 3 is a front view and a bottom view of the head of FIG. 4 is a cross-sectional view taken along line F4-F4 of FIG. FIG. 5 is a cross-sectional view taken along line F5-F5 of FIG. 6 is a cross-sectional view taken along line F6-F6 of FIG.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a view showing a golf club set 2 according to an embodiment of the present invention. The golf club set 2 is an iron golf club set. The real loft angle L1 of the iron type golf club is usually in the range of 15 degrees to 70 degrees.

  The club set 2 includes a plurality of iron type golf clubs 4 having different real loft angles L1. The golf club set 2 has eight golf clubs 4. The number of clubs in the golf club set 2 is two or more. From the viewpoint of revealing the effects of the present invention, the number n of clubs is preferably 3 or more, more preferably 5 or more, and particularly preferably 6 or more. According to the golf rules, the number of clubs that can be used during play is limited. In this respect, the number n of clubs is preferably 12 or less, more preferably 11 or less, and still more preferably 10 or less.

  Each of the golf clubs 4 has a shaft sf, a head hd, and a grip gp. A head hd is attached to the tip of the shaft sf. A grip gp is attached to the rear end portion of the shaft sf.

  The eight golf clubs 4 are the first golf club c1, the second golf club c2, the third golf club c3, the fourth golf club c4, and the fifth golf club c5 in ascending order of the real loft angle L1. , Sixth golf club c6, seventh golf club c7 and eighth golf club c8. The lower the count, the smaller the real loft angle L1 of the head hd.

  The first golf club c1 has a shaft sf1, a head hd1, and a grip gp. The second golf club c2 has a shaft sf2, a head hd2, and a grip gp. The third golf club c3 has a shaft sf3, a head hd3, and a grip gp. The fourth golf club c4 has a shaft sf4, a head hd4, and a grip gp. The fifth golf club c5 has a shaft sf5, a head hd5, and a grip gp. The sixth golf club c6 has a shaft sf6, a head hd6, and a grip gp. The seventh golf club c7 has a shaft sf7, a head hd7, and a grip gp. The eighth golf club c8 has a shaft sf8, a head hd8, and a grip gp.

  The golf clubs 4 constituting the golf club set 2 have different club lengths. In order of increasing club length, first golf club c1, second golf club c2, third golf club c3, fourth golf club c4, fifth golf club c5, sixth golf club c6, The seventh golf club c7 and the eighth golf club c8. The lower the count, the longer the club length. The club length is adjusted mainly by the length of the shaft sf. Golf clubs 4 having the same length may be included.

  Although not shown, the lie angles are different in the golf club 4 constituting the golf club set 2. The first golf club c1, the second golf club c2, the third golf club c3, the fourth golf club c4, the fifth golf club c5, the sixth golf club c6, and the seventh Golf club c7 and eighth golf club c8. The lower the count, the smaller the lie angle. Golf clubs 4 having the same lie angle may be included.

  In the embodiment of FIG. 1, the first golf club c1 is a 4th iron, the second golf club c2 is a 5th iron, the third golf club c3 is a 6th iron, and a fourth golf. The club c4 is a 7 iron, the fifth golf club c5 is an 8 iron, the sixth golf club c6 is a 9 iron, the seventh golf club c7 is a pitching wedge (PW), The eighth golf club c8 is an approach wedge (AW). In the present invention, the count of the golf club 4 included in the golf club set 2 is not limited.

  FIG. 2 is a perspective view of the head hd2 of the golf club c2 (5 iron). FIG. 3 is a front view and a bottom view of the head hd2. In FIG. 3, the front view is drawn on the upper side and the bottom view is drawn on the lower side. Hereinafter, the head hd2 will be described as an example, but these structures are the same for the heads hd of other counts.

  The head hd2 has a face 5, a hosel 6 and a sole 7. The golf club head hd has a shaft hole 10 for mounting a shaft. The shaft hole 10 is provided in the hosel 6.

  The material of the head hd2 and the face 5 is not limited. The face 5 may be metal or non-metal. Examples of the metal include iron, stainless steel, maraging steel, pure titanium, and a titanium alloy. An example of iron is soft iron (low carbon steel having a carbon content of less than 0.3 wt%). An example of a nonmetal is CFRP (carbon fiber reinforced plastic).

  The head hd2 has a plurality of face grooves gv. The face groove gv is also simply referred to as a groove. The method for forming the face groove gv is not limited. Examples of the method for forming the face groove gv include forging, pressing, casting, and cutting (engraving).

  A part of the face 5 is subjected to a process for adjusting the surface roughness. A typical example of this processing is shot blast processing. 2 and 3 show a boundary line k1 between an area where shot blast processing is performed and an area where shot blast processing is not performed. The boundary line k1 is a toe side boundary line k1t and a heel side boundary line k1h. Shot blasting is applied to an area between the toe side boundary line k1t and the heel side boundary line k1h. All face grooves gv are provided in the area where the shot blasting process has been performed. Shot blasting is not applied to the area on the toe side of the toe side boundary line k1t. Shot blasting is not performed on the heel side area from the heel side boundary line k1h. The toe side boundary line k1t and the heel side boundary line k1h are visually recognized by the presence or absence of the shot blasting process. By this shot blasting process, the surface roughness is increased. This large surface roughness can increase the backspin rate of the ball. The ball tends to stop near the drop point due to the increased backspin rate. By increasing the backspin rate, it may be easier to stop the ball at the target point. In particular, this increase in the backspin rate is beneficial for shots aimed at the green and approach shots. As shown in FIGS. 2 and 3, the boundary line k1t and the boundary line k1h are substantially parallel.

  The face 5 has a land area LA. The land area LA refers to a portion of the surface (face surface) of the face 5 where no groove is formed. The land area LA is substantially a plane if fine irregularities due to shot blasting or the like are ignored.

  4 is a cross-sectional view taken along line F4-F4 of FIG. The position of the F4-F4 line in the toe-heel direction divides the distance between the measurement position of the toe side sole width d1 and the measurement position of the heel side sole width d2 into two equal parts (see FIG. 3). A recess 12 is provided on the back side of the head hd2. The head hd2 is a so-called cavity back type.

  As shown in FIG. 4, the head hd <b> 2 includes a head body 14 and a face plate 16. The head body 14 has an opening (not shown) corresponding to the shape of the face plate 16. The face plate 16 is fitted into the opening. In FIG. 3, the outline 18 of the face plate 16 is drawn.

[Real loft angle L1 of each club]
The real loft angle L1 of the golf club 4 constituting the golf club set 2 is set to L1 (1), L1 (2),..., L1 (n) in order from the club having the smallest real loft angle L1. In the set 2, the real loft angle L1 is larger as the count is larger. That is, this set 2 satisfies L1 (1) <L1 (2) <... <L1 (n).

  The golf club set 2 includes a golf club 4 having a real loft angle L1 of 40 ° or less and a golf club 4 having a real loft angle L1 exceeding 40 °. In the golf club set 2, the golf club 4 having a real loft angle L1 of 40 ° or less is a club (from the 4th iron to the 8th iron) having a smaller real loft angle L1 than the 9th iron and the 9th iron. Examples of other clubs having a real loft angle L1 smaller than 40 ° include a third iron, a second iron, and a first iron. In the golf club set 2, the golf club 4 having a real loft angle L1 exceeding 40 ° is a pitching wedge and an approach wedge. Examples of other clubs having a real loft angle L1 exceeding 40 ° include a sand wedge and a lob wedge.

  The club set 2 includes a golf club having a real loft angle L1 of 50 ° or more. The golf club 4 having a real loft angle L1 of 50 ° or more is an approach wedge. Examples of other clubs having a real loft angle L1 of 50 ° or more include a sand wedge and a lobe wedge.

  The difference in real loft angle L1 between adjacent counts, that is, [L1 (m) −L1 (m−1)] is usually 2 ° or more and 6 ° or less.

[Measurement position of toe side sole width d1]
In the present application, a toe side sole width d1 is defined. The measurement position of the width d1 in the toe-heel direction is the toe side end of the face groove gv (see FIG. 3).

[Measurement position of heel side sole width d2]
In the present application, a heel side sole width d2 is defined. The measurement position of the width d2 in the toe-heel direction is the heel side end of the face groove gv (see FIG. 3).

[Measurement method of sole width d1]
FIG. 5 is a cross-sectional view taken along line F5-F5 of FIG. FIG. 5 is a cross-sectional view at the toe side end of the face groove gv. This cross section is perpendicular to the face surface. The sole width d1 is determined based on the contour line PL1 of this cross section. In the contour line PL1, the end point p1 on the face side of the sole 7 is determined. Further, on the contour line PL1, an end point b1 on the back side of the sole 7 is determined. The face-back direction distance between the end point p1 and the end point b1 is the sole width d1.

  The end point p1 is the foremost point of the contour line PL1.

The end point b1 is defined as follows. When the radius of curvature of the contour line PL1 is viewed from the center side to the back side of the sole 7, the position where the radius of curvature is 10.0 mm or less for the first time is defined as the end point b1.

[Measurement method of sole width d2]
6 is a cross-sectional view taken along line F6-F6 of FIG. This cross section is perpendicular to the face surface. The sole width d2 is determined based on the contour line PL2 of this cross section. At the contour line PL2, the end point p2 on the face side of the sole 7 is determined. Furthermore, the end point b2 on the back side of the sole 7 is determined on the contour line PL2. The face-back direction distance between the end point p2 and the end point b2 is the sole width d2.

  The end point p2 is the foremost point of the contour line PL2.

The end point b2 is defined as follows. When the radius of curvature of the contour line PL2 is viewed from the center side to the back side of the sole 7, the position where the radius of curvature is 10.0 mm or less for the first time is defined as the end point b2.

  In the present application, the toe side sole width d1 of a plurality of clubs constituting the set is d1 (1), d1 (2),..., D1 (n) in order from the club having the smallest real loft angle L1. The maximum value of the toe side sole width d1 is d1max, and the minimum value of these toe side sole widths d1 is d1min.

  For example, in the embodiment of FIG. 1 described above, d1 (1) is the toe side sole width d1 of the 4th iron, d1 (2) is the toe side sole width d1 of the 5th iron, and d1 (3) is The toe side sole width d1 of the 6th iron, d1 (4) is the toe side sole width d1 of the 7th iron, d1 (5) is the toe side sole width d1 of the 8th iron, and d1 (6) Is the toe side sole width d1 of the 9th iron, d1 (7) is the toe side sole width d1 of the pitching wedge, and d1 (8) is the toe side sole width d1 of the approach wedge.

  In the present application, the heel side sole width d2 of the plurality of clubs constituting the set is d2 (1), d2 (2),..., D2 (n) in order from the club having the smaller real loft angle L1. The maximum value of these heel side sole widths d2 is d2max, and the minimum value of these heel side sole widths d2 is d2min.

  For example, in the embodiment of FIG. 1 described above, d2 (1) is the heel side sole width d2 of the 4th iron, d2 (2) is the heel side sole width d2 of the 5th iron, and d2 (3) is The heel side sole width d2 of the 6th iron, d2 (4) is the heel side sole width d2 of the 7th iron, and d2 (5) is the heel side sole width d2 of the 8th iron, d2 (6) Is the heel side sole width d2 of the 9th iron, d2 (7) is the heel side sole width d2 of the pitching wedge, and d2 (8) is the heel side sole width d2 of the approach wedge.

  In the present application, the bounce angles θ1 of the plurality of clubs constituting the set are set to θ1 (1), θ1 (2),..., Θ1 (n) in order from the club having the smallest real loft angle L1. The maximum value of the angle θ1 is θ1max, and the minimum value of these bounce angles θ1 is θ1min.

  For example, in the embodiment of FIG. 1 described above, θ1 (1) is the bounce angle θ1 of the 4th iron, θ1 (2) is the bounce angle θ1 of the 5th iron, and θ1 (3) is the 6th iron. The bounce angle θ1, θ1 (4) is the bounce angle θ1 of the 7th iron, θ1 (5) is the bounce angle θ1 of the 8th iron, and θ1 (6) is the bounce angle θ1 of the 9th iron. , Θ1 (7) is the bounce angle θ1 of the pitching wedge, and θ1 (8) is the bounce angle θ1 of the approach wedge.

[Measurement position of bounce angle θ1]
In the present application, the measurement position of the bounce angle θ1 in the toe-heel direction is a position dv1 that bisects the measurement position of the toe side sole width d1 and the measurement position of the heel side sole width d2 (see FIG. 3). ).

[Measurement method of bounce angle θ1]
4 is a cross-sectional view taken along line F4-F4 of FIG. This cross section is perpendicular to the face surface. The bounce angle θ1 is determined based on the contour line PL3 of this cross section. In the contour line PL3, the end point p3 on the face side of the sole 7 is determined. Furthermore, an end point b3 on the back side of the sole 7 is determined on the contour line PL3. A face-back direction distance between the end point p3 and the end point b3 is a sole width dc.

  The end point p3 is the forefront point of the contour line PL3.

The end point b3 is defined as follows. When the curvature radius of the contour line PL3 is viewed from the center side to the back side of the sole 7, the position where the curvature radius is 10.0 mm or less for the first time is defined as the end point b3.

  The center point Cp is at a position that bisects the end point p3 and the end point b3 in the face-back direction (see FIG. 4). The angle formed by the tangent TL1 of the contour line PL3 at the center point Cp and the horizontal plane h is the bounce angle θ1. The bounce angle θ1 is measured in the head in the reference state. This reference state will be described later.

  Preferably, the bounce angle θ1 (°) satisfies θ1 (1) ≦ θ1 (2) ≦ ... ≦ θ1 (n).

  Preferably, the d1max (mm) and the d1min (mm) are substantially the same. “Substantially the same” means that (d1max−d1min) / d1max is 0.08 or less.

  Preferably, the d2max (mm) and the d2min (mm) are substantially the same. “Substantially the same” means that (d2max−d2min) / d2max is 0.08 or less.

  Preferably, the difference (d1max−d1min) is 1.0 mm or less. More preferably, the difference (d1max−d1min) is 0.8 mm or less. More preferably, the difference (d1max−d1min) is 0.5 mm or less. The lower limit is preferably 0 mm or more, and may be 0.1 mm or more from the viewpoint of dimensional errors.

  Preferably, the difference (d2max−d2min) is 1.0 mm or less. More preferably, the difference (d2max−d2min) is 0.8 mm or less. More preferably, the difference (d2max−d2min) is 0.5 mm or less. The lower limit is preferably 0 mm or more, and may be 0.1 mm or more from the viewpoint of dimensional errors.

  It has been found that a new effect can be produced by suppressing the difference (d1max−d1min) and the difference (d2max−d2min).

The conventional iron set has the following specification A or specification B.
[Specification A]: The larger the count, the wider the sole width. In other words, the smaller the count, the narrower the sole width.
[Specification B]: The smaller the count, the wider the sole width. In other words, the larger the count, the narrower the sole width.

  In the above specification A, the long iron has a narrow sole width and the short iron has a wide sole width. On the other hand, in the above specification B, the sole width of the long iron is wide and the sole width of the short iron is narrow. A normal iron set is the above specification A.

  In the club set, in order to unify the swing balance, the larger the count, the greater the head weight. Therefore, in the above specification B, the smaller the count, the wider the sole width and the smaller the head weight. In this case, a head with a small count has a small head weight and a large weight distribution to the sole. Therefore, the weight distributed to portions other than the sole is small, and the degree of freedom of weight distribution is small. For this reason, a head with a small count (particularly a long iron) has a low degree of freedom in head design. For example, the design such as the position of the center of gravity, the head size, and the moment of inertia is restricted.

  In the club set of the present embodiment, the difference (d1max−d1min) and the difference (d2max−d2min) are limited. Therefore, even if the head has a small count, there are few restrictions on the head design.

  Short irons usually tend to swing down. Therefore, in a short iron, the influence which a sole receives from the ground is large. When the sole width is too wide in the short iron, the grounding resistance is excessive and the operability is easily lost. When the sole width is too wide in a short iron, it is difficult to obtain good omission.

  In the club set of the present embodiment, since the difference (d1max−d1min) and the difference (d2max−d2min) are limited, the sole width does not become excessive even in a short iron having a large count. Therefore, in a short iron, the operability is good and the omission is good. “Good removal” means that there is little resistance from the ground and it is easy to swing out.

  Long irons usually tend to swing to level blow. Therefore, in a long iron, it is preferable to hit the ball by sliding the sole on the ground surface. If the sole width is too narrow in a long iron, it is easy to duff.

  In the club set of the present embodiment, the difference (d1max−d1min) and the difference (d2max−d2min) are limited. Therefore, even in a long iron with a small count, the sole width does not become excessive. Therefore, duffing with a long iron is suppressed.

  Long irons are difficult to hit because they have a long club and few lofts. A long iron with a narrow sole width gives an image that seems to stab on the ground. A long iron with a narrow sole width gives an easy-to-drift image. These bad images are prone to miss shots. In the present embodiment, the sole width does not become excessive even in a long iron with a small count. Therefore, miss shots can be reduced.

  First of all, long irons have few lofts, so it is difficult to obtain an appropriate trajectory height. In addition, a long iron with a narrow sole width has a high center of gravity. This high center of gravity results in a low trajectory. In the present embodiment, the sole width does not become excessive even in a long iron with a small count. Therefore, it is easy to obtain an appropriate trajectory height.

  At the address, many golfers place the sole surface on the ground (lawn). The stability of the head at the address is also referred to as “sitting”. A stable head is stable and easy to hold. When there is little variation in sitting between counts, the face orientation at the address tends to be stable between counts.

  It was found that by limiting the difference (d1max−d1min) and the difference (d2max−d2min), the difference in sitting between different counts is reduced. For this reason, the orientation of the head at the address tends to be stable. In the head of the present embodiment, it is easy to address the face toward the target with any number. Due to the stability of the sitting, it was found that there was little variation in hitting direction between different counts.

  Further, when the change in the bounce angle and the change in the sole width overlap, the difference in the sitting between the different counts can be enlarged. In the head according to the present embodiment, even when the bounce angle is changed, variation in sitting between counts can be suppressed.

  In the iron set, “performance flow” is important. This “performance flow” is the continuity of performance between different counts. Examples of this performance include flight distance, trajectory, and backspin speed. In the iron set, it is preferable that the performance of each count club gradually changes as the count changes. In such an iron set, it is easy to obtain performance suitable for each count. An iron set having a good performance flow facilitates selection of an appropriate count by a golfer. On the other hand, it is not preferable that the performance protrudes at a certain count or the direction of change in performance is reversed. An iron set with a poor performance flow makes it difficult for a golfer to select an appropriate count.

  Conventionally, from the viewpoint of improving the flow of performance, it has been considered that the sole width should be changed as the count changes. However, the change in performance between adjacent counts is likely to be excessive due to the synergy between changes in the sole width and changes in other specifications (loft angle, head weight, club length, bounce angle, center of gravity, etc.) . By suppressing the change in the sole width, the change in performance between adjacent counts is unlikely to be excessive. By suppressing the change in the sole width, it is easy to obtain a club set having a good performance flow.

From the viewpoint of the performance flow, a preferable club set satisfies the following formulas (f1) and (f2) or the following formulas (f3) and (f4).
d1 (1) ≦ d1 (2) ≦ ・ ・ ・ ≦ d1 (n) (f1)
d2 (1) ≦ d2 (2) ≦ ・ ・ ・ ≦ d2 (n) (f2)
d1 (1) ≧ d1 (2) ≧ ・ ・ ・ ≧ d1 (n) (f3)
d2 (1) ≧ d2 (2) ≧ ・ ・ ・ ≧ d2 (n) (f4)

From the viewpoint of suppressing duffing in a club with a small count and improving operability in a club with a large count, the bounce angle θ1 (°) preferably satisfies the following formula (f5), and the following formula (f6) It is more preferable to satisfy | fill, and it is more preferable to satisfy | fill following formula (f7).
θ1 (1) ≦ θ1 (2) ≦ ・ ・ ・ ≦ θ1 (n) (f5)
θ1 (1) <θ1 (n) (f6)
θ1 (1) <θ1 (2) <... <θ1 (n) (f7)

  The toe side sole width d1 is not limited. From the viewpoint of suppressing duffing with a long iron, the toe side sole width d1 is preferably 18 mm or more, more preferably 20 mm or more, and further preferably 23 mm or more. From the viewpoint of operability with a short iron, the toe side sole width d1 is preferably 30 mm or less, more preferably 28 mm or less, and even more preferably 25 mm or less.

  The heel side sole width d2 is not limited. From the viewpoint of suppressing duffing with a long iron, the heel side sole width d2 is preferably 12 mm or more, more preferably 14 mm or more, and further preferably 17 mm or more. From the viewpoint of operability with a short iron, the heel side sole width d2 is preferably 24 mm or less, more preferably 22 mm or less, and even more preferably 19 mm or less.

  The ratio (d1 / d2) is not limited. From the viewpoint of suppressing an excessive weight distribution to the heel portion and avoiding an extremely short center of gravity distance, the ratio (d1 / d2) is preferably 0.75 or more, more preferably 1.0 or more, and 1.2 or more. Further preferred. From the viewpoint of suppressing excessive weight distribution to the toe portion and avoiding an extremely long center of gravity distance, the ratio (d1 / d2) is preferably 2.5 or less, more preferably 2.0 or less, and 1.5 or less. Further preferred. These preferable ratios (d1 / d2) are preferably satisfied in all counts. The center of gravity distance is the distance between the shaft axis and the center of gravity of the head.

When the sole width is too large in the long iron, the back side of the sole portion can be visually recognized at the time of addressing. In this case, concentration on the face surface at the time of addressing may be reduced or a sense of incongruity may occur. From this viewpoint, it is preferable that all the count heads satisfy the following (a).
(A) In the toe-heel direction range where the face surface exists, the top surface of the head is positioned closest to the back side.

  When this (a) is satisfied, the back side of the sole portion cannot be seen at the time of addressing. Therefore, it is easy to concentrate on the face surface and there is little discomfort. The definitions of the reference state, the toe-heel direction, and the face-back direction are as follows. The “back side” is determined according to the face-back direction.

[Standard state]
The reference state is a state in which the head is placed on the horizontal plane h at a predetermined lie angle and real loft angle. More specifically, the reference state means that the center axis line z of the shaft hole of the head is arranged in an arbitrary vertical plane VP1, the center axis line z is inclined with respect to the horizontal plane h at the lie angle, and the face surface is vertical. It is in a state where it is tilted at the real loft angle with respect to the plane VP1 and grounded to the horizontal plane h (see FIG. 4). The vertical plane VP1 is a plane parallel to the vertical line.

[Toe-heel direction]
In the head in the reference state, a direction parallel to the line of intersection between the VP1 and the horizontal plane h is a toe-heel direction.

[Face-back direction]
A direction perpendicular to the toe-heel direction and parallel to the horizontal plane h is a face-back direction.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

  In the following, a test was performed using a set having three clubs.

[Example 1]
Stainless steel was cast to obtain a head before polishing. The face groove was formed by cutting. The head width of Example 1 was obtained by adjusting the sole width and the bounce angle by polishing. Heads of No. 4 iron, No. 7 iron and pitching wedge were produced. In all the counts, the sole width from the toe position (measurement position of the sole width d1) to the heel position (measurement position of the sole width d2) was gradually narrowed toward the heel side.

  A shaft suitable for each count was bonded to the head. The product name “NS PRO 950S” manufactured by Nippon Shaft Co., Ltd. was used as the shaft. A grip was attached to obtain a golf club according to Example 1. The length of the 4th iron was 38.5 inches, the length of the 7th iron was 37.0 inches, and the length of the pitching wedge was 35.5 inches.

[Examples 2 and 3]
The pre-polishing head obtained in Example 1 was used. The sole width and bounce angle were adjusted by polishing. In the same manner as Example 1, heads according to Examples 2 and 3 were obtained. In any of the examples, the sole width from the toe position (measurement position of the sole width d1) to the heel position (measurement position of the sole width d2) is gradually narrowed toward the heel side in all counts. It was.

  The same shaft and grip as in Example 1 were attached to obtain golf clubs according to Examples 2 and 3.

[Comparative Examples 1 and 2]
The pre-polishing head obtained in Example 1 was used. The sole width and bounce angle were adjusted by polishing. In the same manner as in Example 1, the heads according to Comparative Examples 1 and 2 were obtained. In any comparative example, the sole width from the toe position (measurement position of the sole width d1) to the heel position (measurement position of the sole width d2) is gradually narrowed toward the heel side in all the counts. It was.

  The same shaft and grip as in Example 1 were attached to obtain golf clubs according to Comparative Examples 1 and 2.

  The evaluation method is as follows.

[Good omission]
Ten golfers with handicap between 0 and 10 placed a semi-rough ball and actually hit the ball to evaluate the ability to slip. The product name “Srixon Z-STAR” manufactured by SRI Sports was used as the ball. This evaluation is a sensory evaluation. Each golfer made a five-point scale with a maximum score of 5. Five points are the highest evaluation, one point is the lowest evaluation, and the lower the score, the lower the evaluation. The average score of 10 golfers is shown in Table 1 below.

[Ease of setting]
The 10 golfers evaluated the ease of holding at the same time as the evaluation of the omission. This evaluation is a sensory evaluation. Each golfer made a five-point scale with a maximum score of 5. Five points are the highest evaluation, one point is the lowest evaluation, and the lower the score, the lower the evaluation. The average score of 10 golfers is shown in Table 1 below.

[Deviation of hitting direction]
The 10 golfers placed balls on the fairway and hit the target. Each golfer hit five balls at each count. The product name “Srixon Z-STAR” manufactured by SRI Sports was used as the ball. The displacement distance (yard) from the target direction was measured. This deviation distance is a distance between the straight line connecting the hitting point and the target point and the final hit point of the hit ball. This shift distance was a positive value both when the shift was on the right side and when shifted to the left side. The average of the measured values of 10 people is shown in Table 1 below. The 10 golfers mentioned above are of the type in which the sole surface is grounded and addressed.

[Direction of hitting ball as a set]
The maximum width of deviation in the hitting direction combining the three counts was regarded as hitting directionality. The hitting directionality was evaluated in four stages, ◎, ○, Δ, and ×. These meanings are as follows.
A: Variation in hitting direction as a whole set is 5 yards or less.
A: The variation in the hitting direction as a whole set is greater than 5 yards and less than 10 yards.
(Triangle | delta): The variation in the hitting direction as a whole set is more than 10 yards and 15 yards or less.
X: The variation in the hitting direction as a whole set is larger than 15 yards.

  The variation in the hitting direction as a whole set was calculated using the test data of the above-mentioned [deviation in hitting direction]. However, the deviation distance is positive when the right side is shifted, and negative when it is shifted to the left side. For each count, an average value of the displacement distances of 10 people was calculated. When the maximum value of the three count shift distances is D1 and the minimum value of the three count shift distances is D2, the difference (D1-D2) is “in the hitting direction of the entire set. It was said to be "variable".

  In the example, the variation in the hitting direction was small because there was little variation in sitting between counts. In the embodiment, since the difference in sitting between the counts is small, the ease of holding is highly evaluated in all the counts.

  As shown in Table 1, the examples have higher evaluations than the comparative examples. From this result, the superiority of the present invention is clear.

  The present invention can be applied to any iron golf club set.

2 ... Golf club set 4 ... Golf club 5 ... Face 6 ... Hosel 7 ... Sole 12 ... Recess (cavity)
sf ... shaft hd ... head gp ... grip L1 ... real loft angle gv ... face groove hd1-hd8 ... head (the smaller the number, the smaller the real loft angle)
c1 to c8... golf club (the smaller the number, the smaller the real loft angle)
LA ... Land area

Claims (2)

n (n is an integer of 6 or more) iron golf clubs,
Each of these clubs has a head and a plurality of face grooves provided in the head,
The toe side sole width d1 of these clubs is d1 (1), d1 (2),..., D1 (n) in order from the club with the smallest real loft angle L1, and the maximum of these toe side sole widths d1. The value is d1max, and the minimum value of these toe side sole widths d1 is d1min.
The heel side sole width d2 of these clubs is d2 (1), d2 (2),..., D2 (n) in order from the club with the smallest real loft angle L1, and the maximum of these heel side sole widths d2 The value is d2max, and the minimum value of the heel side sole width d2 is d2min.
The club bounce angle θ1 is set to θ1 (1), θ1 (2),..., Θ1 (n) in order from the club having the smallest real loft angle L1, and the maximum value of these bounce angles θ1 is θ1max. And when the minimum value of these bounce angles θ1 is θ1min,
θ1 (1) ≦ θ1 (2) ≦ ・ ・ ・ ≦ θ1 (n) is satisfied,
The d1max and the d1min are substantially the same,
The d2max and the d2min are substantially the same,
The difference (d1max−d1min) is 1.0 mm or less,
The difference (d2max−d2min) is 1.0 mm or less,
d1 (1) ≧ d1 (2) ≧ ・ ・ ・ ≧ d1 (n) is satisfied,
An iron golf club set that satisfies d2 (1) ≧ d2 (2) ≧... ≧ d2 (n).
However, the measurement position in the toe-heel direction of the toe side sole width d1 is the toe side end of the longest face groove, and the measurement position in the toe-heel direction of the heel side sole width d2 is the longest face groove. This is the heel side end. The difference (d1max-d1min) is 0.8 mm or less,
The iron golf club set according to claim 1, wherein the difference (d2max−d2min) is 0.8 mm or less.

Images