JP2002210046A - Golf club for through-the-green - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club for through-the-green wherein both of the lowering of the gravity center of the head and the increase in the moment of inertia can be made possible. SOLUTION: This golf club is equipped with a head 1 at the distal end of a shaft 4. In such a golf club, the height H from the reference surface B of the leading edge 5 of the head 1 when an addressing position is taken by bringing the sole surface 3 of the head 1 into contact with the reference surface B is set to be 10 mm or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club for through the green, and more particularly, to a golf club capable of achieving both a low center of gravity of a head and an increase in moment of inertia.

[0002]

2. Description of the Related Art Conventionally, the center of gravity of a golf club head has been reduced, and the distance between a point at which a perpendicular line drawn from the center of gravity to the face surface intersects the face surface and the upper end of the face surface, that is,
It is common practice to provide a golf club capable of obtaining a hit ball with a small backspin by increasing the effective hitting distance.

As a means for lowering the center of gravity of the head as described above, it has been practiced to relatively increase the mass on the sole side of the head. However, when the mass on the sole side is increased, there is a disadvantage that the degree of freedom for increasing the moment of inertia of the head is reduced. That is,
If weight distribution to the sole side necessary for lowering the center of gravity is excessively performed, weight distribution to the periphery of the head for increasing the sweet area cannot be performed. Therefore, it has been considered that it is difficult to simultaneously reduce the center of gravity of the head and increase the moment of inertia.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a golf club for through-the-green golf clubs, which makes it possible to reduce the center of gravity of the head and increase the moment of inertia.

[0005]

According to the present invention, there is provided a golf club for a through-the-green golf club having a head at a tip end of a shaft. The height of the leading edge of the head from the reference plane is 10 mm or more when the contact position is established.

[0006] By setting the height of the leading edge of the head from the reference plane to 10 mm or more, unlike the conventional case where the leading edge is close to the reference plane, the sole surface of the head is different from the conventional case. Since it extends below the edge, it is possible to reduce the center of gravity without concentrating the weight distribution of the head on the sole side, and it is possible to achieve both a lower center of gravity of the head and an increase in the moment of inertia. .

In the above golf club, it is preferable that the original loft angle of the head is 8 degrees or less, and the angle difference obtained by subtracting the original loft angle from the real loft angle is 1 degree or more. Such a shape is advantageous for achieving both a low center of gravity of the head and an increase in the moment of inertia.

In the present invention, the moment of inertia of the head measured around an axis passing through the center of gravity of the head and perpendicular to the face surface is preferably 2000 g · cm ² or more.
If such a moment of inertia is set, the sweet area can be expanded.

The golf club for through-the-green in the present invention is a general term for golf clubs mainly used in through-the-green, except for putters, except for wood golf clubs, iron golf clubs, wood golf clubs and irons. So-called utility golf clubs, chippers, jiggers, and the like that are not classified as any of the golf clubs are included.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 illustrates a golf club for through the green according to an embodiment of the present invention.
FIG. 11 is a diagram for explaining the definition of the dimensions of the golf club, and FIGS. 12 to 21 are diagrams for explaining a method of measuring the moment of inertia of the head. In addition, FIG.
The golf club shown in FIG. 21 does not always correspond to the configuration of the present invention. Further, although the drawings illustrate a right-handed golf club or head, the present invention includes a left-handed golf club or head.

As shown in FIG. 1, the golf club according to the present embodiment has a structure in which a head 1 is attached to a tip of a shaft 4, and the head 1 has a face surface 2 and a sole surface 3. . Here, the head 1 is placed on the horizontal reference plane B.
When the sole position 3 is brought into contact with the sole surface 3 to take an address position, the height H of the leading edge 5 of the head 1 from the reference plane B is 10 mm or more.

The address position in the present invention is
In the front view of the head shown in FIG. 2A, the head 1 is set at the lie angle, and in the plan view of the head shown in FIG. 2B, the shaft axis S and the leading edge 5 are parallel to each other. Refers to the case where it is set to The installation according to the lie angle is a state where the gap between the round of the sole surface 3 and the reference surface B is substantially equal on the toe side and the heel side in FIG. When the round of the sole surface 3 is not clear, the score line drawn on the face surface 2 and the reference surface B are set in parallel. If the round of the sole surface 3 is not clear and the score line is not linear, and the parallel with the reference surface B cannot be determined,
The lie angle (degree) is set by (100-club length (inch)). For example, if the club length is 44 inches, the lie angle is 100-44 = 56 degrees.

The club length is measured by a measuring method defined by the Japan Golf Equipment Association. As a measuring instrument,
Club Major II manufactured by Kamoshita Seisensho Co., Ltd. That is, as shown in FIGS. 10 and 11, when the heel end is set as the base point P ₁ and the grip end is set as the end point P ₂ , the distance C between P ₁ and P ₂ is set as the club length.

In the address position according to the present invention, the direction of the leading edge 5 is set at right angles to the direction indicated by the face surface 2. FIG. 2B shows a case where the leading edge 5 is a straight line. If the leading edge 5 is a curve, the direction is set by a line L indicating a direction perpendicular to the direction indicated by the face surface 2 as shown in FIG. The leading edge 5 is where the head 1 projects the most in the direction of the flying ball as shown in FIG.

The direction of the face surface is specified as described above,
Measurement of the head dimensions performed with the address position set is performed by a measuring instrument such as a golfer's ball head measuring table manufactured by Shoho Company, a golf club angle measuring instrument manufactured by Golf Galley II, a golf club gauge manufactured by Golf Smith, etc. Is possible. Such a measuring device may be any known device, and is not particularly limited in the present invention.

At the address position, the height H of the leading edge 5 of the head 1 from the reference plane B is set to 1
By setting the thickness to 0 mm or more, preferably 15 mm or more, and more preferably 200 mm or more, the sole surface 3 extends below the leading edge 5, so that the weight distribution of the head 1 is not concentrated on the sole side. A low center of gravity can be achieved. Thereby, it is possible to increase the distance between the point where the perpendicular line drawn from the center of gravity of the head 1 to the face surface 2 and the face surface 2 intersects and the upper end of the face surface, that is, the effective hit point distance La shown in FIG. Become. By increasing the effective hitting distance La, it is possible to supply a golf club capable of obtaining a hit ball with a low back spin as a whole.

In the present invention, the original loft angle of the head and the angle difference obtained by subtracting the original loft angle from the real loft angle are set as follows in order to achieve both a low center of gravity of the head and an increase in the moment of inertia. Is preferred.

The original loft angle is an angle θo between the face surface 2 and the sole surface 3 in a side view from the toe side when the address position is set by the head shown in FIG.

The example shown in FIG. 3 is a case where the face surface 2 is a flat surface.
As shown in the figure, the measurement is performed by a tangent f to the midpoint m in the vertical direction of the face. When the position of the midpoint m in the face vertical direction changes depending on the position in the face horizontal direction, the face vertical direction is set at the center in the face horizontal direction. The center in the face left-right direction is set in the middle of the score line pattern. If the score line is an asymmetric pattern, the score line is set at the center of the face in the left-right direction at a position 21 mm above the leading edge along the face surface 2. Upper, lower, left and right ends of the face 2 are defined by edges of the face 2.

The example shown in FIG. 3 is a case where the sole surface 3 is a plane, but when the sole surface 3 is a curved surface, as shown in FIG. Measure the original loft angle at the position where the head is stable.
The procedure on the measuring instrument is to adjust the lie angle, fix the head at a stable position, and measure the original loft angle. By the way, in the head where the original loft angle is not the same as the real loft angle, a face angle of a hook or a slice occurs. become.

In the present invention, the original loft angle is preferably 8 degrees or less, more preferably 5 degrees or less, further preferably 3 degrees or less, and most preferably 1 degree or less. When the original loft angle is large, FIG.
In the side view as viewed from the toe side when the head shown in FIG. 4B is naturally placed, as shown in FIG. 4A, the position of the center of gravity projected on the face surface 2 becomes higher, and the effective hitting distance La Becomes smaller. On the other hand, when the original loft angle is small, as shown in FIG. 4B, the position of the center of gravity projected on the face surface 2 becomes low, and the effective hitting distance Lb becomes large. By setting the original loft angle within the above range, the effective hitting distance of the head can be increased.

On the other hand, the real loft angle refers to the face surface 2 and the shaft axis S in the side view seen from the toe side when the address position is taken by the head shown in FIG.
And the angle θr formed by The golfer grasps the grip of the golf club, hits the ball on the face of the head along the shaft, and the loft angle for raising the ball depends on the real loft angle between the face 2 and the shaft axis S. I do. As a procedure on the measuring instrument,
With the lie angle adjusted, the face angle is fixed at 0 degree, and the real loft angle is measured.

The above-mentioned measurement of the original loft angle and the real loft angle is performed by using a golfer's head measuring table manufactured by Shoho Company, a golf club angle measuring device manufactured by Golf Galley, a golf club gauge manufactured by Golf Smith, and the like. It is possible with a measuring instrument. Such a measuring device may be any known device, and is not particularly limited in the present invention.

In the present invention, the angle difference obtained by subtracting the original loft angle from the real loft angle is preferably at least 1 degree, more preferably at least 3 degrees, still more preferably at least 5 degrees, and most preferably at least 7 degrees. In the present invention, the effective hitting distance of the head is increased by reducing the original loft angle. However, when the original loft angle and the real loft angle are the same or substantially the same as in a conventional golf club, the real loft angle is reduced. The loft angle becomes too small, making it difficult to raise the hit ball to obtain a sufficient flight distance. Therefore, in the present invention, in the side view from the toe side when the address position is taken by the head shown in FIG. 6, the real loft angle .theta. In order to make the value smaller than the conventional golf club,
The real loft angle θr becomes larger than the original loft angle θo, and (real loft angle−original loft angle) becomes a positive value and becomes 1 degree or more.

Generally, when the original loft angle and the real loft angle are different, a face angle occurs. More specifically, if the original loft angle is larger than the real loft angle, the slice face (face angle is minus) is used, and if the original loft angle is smaller than the real loft angle, the hook face is used (the face angle is plus). When the face angle occurs, if the head is naturally placed as a golf club, the face will face a direction deviating from the target, which has been a bad impression for general golfers. Therefore, as a general idea, it has been common sense that the original loft angle and the real loft angle are designed to be the same or substantially the same so that the orientation of the face surface in a state of being placed naturally does not matter.

Further, in the present invention, it is preferable to increase the moment of inertia by utilizing that the lowering of the center of gravity of the head does not inhibit the increase of the moment of inertia.

In the present invention, the moment of inertia of the head 1 measured around an axis passing through the center of gravity of the head 1 and perpendicular to the face surface 2 is preferably 2000 g · cm ² or more, more preferably 2200 g · cm ² or more. Preferably, it is 2400 g · cm ² or more. By increasing the moment of inertia as described above, the sweet area of the head can be increased. By enlarging the sweet area, even if the hitting positions of golfers vary, the loss of the flight distance decreases, and as a result, the average flight distance increases.

In the present invention, the moment of inertia of the head can be measured using an inertia moment measuring device as shown in FIG.

The moment of inertia measuring device 11 includes a measuring unit 1
2. Computing unit 14, start lever 15, display unit 16, and operation button 17 are provided. An object to be measured of moment of inertia is placed on measuring unit 12, and start lever 15 is picked up by hand and displaced. This is a device that releases the hand to cause torsional vibration, measures the period of the torsional vibration at this time, measures the inertia moment through the arithmetic unit 14, and displays the numerical value of the inertia moment on the display unit 16.

Incidentally, as the moment of inertia measuring device 11,
An example is a moment of inertia measuring device (model: MOI-005-014) manufactured by Inertia Dynamics.
Such a moment of inertia measuring device may be a known one, and is not particularly limited in the present invention.

The method of measuring the moment of inertia will be described with reference to an example of an iron golf club. As shown in FIG. 13A, the jig 21 is fixed to the measuring section 12 of the moment of inertia measuring device 11 and the moment of inertia Ia is measured. Then, as shown in FIG. 13 (b), the face surface 31 of the iron head 1 is fixed to the upper surface portion 22 of the jig 21, and the moment of inertia Ib is measured. To obtain the moment of inertia. With a normal moment of inertia measuring device,
The value of Ia is automatically tared by a series of procedures using the operation button 17, and the value of (Ib-Ia) is displayed.

The head 1 is a head 1 shown in FIG.
The normal N of the face surface 31 passing through the center of gravity G of FIG.
It is preferable that the rotational axis R of the torsional vibration of the moment of inertia measuring device 11 shown in FIG. 14B be fixed to the moment of inertia measuring device 11 so as to match or substantially match as shown in FIG. The substantially coincidence means that the point where the normal line N passes through the face surface 31 as shown in FIG.
Is a point r passing through the face surface 31, a point g and a point r
Is less than 3 mm, preferably less than 2 mm,
More preferably, it is within 1 mm. By fixing the face surface 31 of the head 1 within this range, the moment of inertia can be measured more accurately. Since the face surface 31 of the iron head 1 is a flat surface and is in close contact with the upper surface portion 22 of the jig 21,
By matching or substantially matching the points g and r, a moment of inertia in a direction perpendicular to the face surface 31 passing through the center of gravity G of the head 1 can be obtained.

The distance d between the point g and the point r does not always need to be within the above range, and the distance d between the point g and the point r is not necessarily required.
(Ib-I)
The correction can be made by subtracting the product of the mass of the head 1 and the square of the distance d from the numerical value of a). According to this correction method, the face surface 3 passing through the center of gravity G of the head 1
A moment of inertia in a direction perpendicular to 1 may be obtained. As described above, the method of measuring the moment of inertia in the direction perpendicular to the face surface 31 passing through the center of gravity G of the head 1 is not particularly limited.

The point g on the face surface 31 of the head 1 is obtained by a center of gravity measuring device 41 as shown in FIG.
The center-of-gravity measuring device 41 includes a support section 42 for supporting the center-of-gravity measurement target on the upper portion, and the support section 42 can know the position of the measurement target supporting the measurement target in equilibrium. That is, in the method of measuring the center of gravity, as shown in FIG. 17, the head 1 is placed on the support portion 42 and a balanced position which does not fall even when the hand is released is searched for. In other words, as shown in FIG. 18A, if the point g is included in the contact portion between the face surface 31 and the support portion 42, the head 1 does not fall even if the hand is put on the support portion 42 and released. As shown in FIG.
If the point g is not included in the contact part between the head 1 and the support part 42, the head 1 falls when placed on the support part 42 and released. This is used to determine the point g.

It is preferable that the support section 42 be a plane or a form that supports at three or more points. Further, the area of the support portion 42 is preferably 15 mm ² or less. The lower limit is not particularly limited as long as the head 1 is supported. The area of the support portion 42 is indicated by the area of a plane portion in the case of a flat surface, and by the area of a figure connecting each point in the case of supporting at three or more points. By setting the area of the support to the above range, the point g can be obtained more accurately.

The plane supported by the support 42 is preferably horizontal or substantially horizontal. Here, substantially horizontal means that the inclination with respect to the horizontal plane is within 2 degrees, preferably 1 degree.
Within a degree. For example, as shown in FIG. 19, whether or not the horizontal level is substantially horizontal is determined by placing the flat plate 51 on the support portion 42 and supporting the flat plate 51 on the flat plate 51 as shown in FIG.
2 can be placed, checked and adjusted. By setting the value in the above range, the point g can be obtained more accurately.

The rotation axis R and the point r of the moment of inertia measuring device 11 are determined by the moment of inertia measuring device 11. The rotation axis R is preferably vertical or substantially vertical. Here, “approximately vertical” means that the inclination with respect to the vertical direction is within 2 degrees, preferably within 1 degree. In order to set the rotation axis R to be vertical or substantially vertical, the level of the measuring instrument can be adjusted by using a level provided in the moment of inertia measuring instrument 11 as a guide, or the measuring instrument can be adjusted to a horizontal plate. It is conceivable to install it on the top. By setting the value in the above range, the moment of inertia about an axis passing through the center of gravity G of the head 1 and perpendicular to the face surface 31 can be measured more accurately.

The plane supported by the upper surface 22 of the jig 21 is preferably horizontal or substantially horizontal. In the present invention, substantially horizontal means that the inclination with respect to the horizontal plane is within 2 degrees, preferably within 1 degree. Whether it is horizontal or substantially horizontal can be checked and adjusted in the same manner as in the example of the support section 42 shown in FIG. 19 described above. By setting the value in the above range, the moment of inertia about an axis passing through the center of gravity G of the head 1 and perpendicular to the face surface 31 can be measured more accurately.

The jig 21 is preferably mounted on the moment of inertia measuring device 11 such that the center of gravity of the jig itself coincides or substantially coincides with the rotation axis R. As shown in FIG. 20, when the position of the center of gravity of the jig 21 is G ′ as shown in FIG. 20, the distance d ′ between the position of the center of gravity G ′ and the rotation axis R is substantially the same.
Is within 2 mm, preferably within 1 mm. By setting the position of the center of gravity of the jig 21 to G ′ within the above range, the face surface 31 passes through the center of gravity G of the head 1.
The moment of inertia about the axis perpendicular to the axis can be measured more accurately.

In order to fix the head 1 and the jig 21, fixing with an adhesive such as a double-sided tape or clay, fixing with an adhesive, fixing with a magnetic force, and the like can be considered. Fixed
This is performed between the face surface 31 of the head 1 and the upper surface portion 22 of the jig 21. If the face surface 31 is flat, the upper surface portion 22 is preferably flat, such as a wood golf club. If the face surface is a convex curved surface, the upper surface portion 22 is preferably a concave curved surface that matches the convex curved surface. That is, it is preferable that both surfaces to be fixed match. In addition, for example, in a case where the face surface 31 'is a convex curved surface but the two surfaces to be fixed do not sufficiently match each other as in the case where the upper surface portion 22 is a flat surface, as shown in FIG. It is conceivable to form and fix so as to match 31 ′ and upper surface portion 22. Needless to say, a fixing means having a mass, such as an adhesive, such as an adhesive 101, is included in a part of the jig, and is tared as in the case of the jig in taring.

[0042]

EXAMPLE (1) Production of Golf Club The conditions of a total mass of 310 g, a vibration frequency of 235 cpm, a swing weight of D0.0, and a club length of 45 inches were shared, and the height of the leading edge of the head at the address position from the reference plane was set. H, original loft angle θ
o, Golf clubs of conventional examples, comparative examples 1 and 2, and examples 1 to 20 having various real loft angles θr were manufactured. However, the swing weight is a value measured by a 14-inch meter.

With respect to the head constituting the golf club, the moment of inertia I (g · cm ² ) about an axis passing through the center of gravity of the head and perpendicular to the face was measured. The results are also shown in Table 1. The moment of inertia is measured by an inertia moment measuring instrument (model: MOI-005-01) manufactured by Inertia Dynamics.
4) As a jig, a measuring weight made by the company (part number: CW
005-001). To fix the head,
As shown in FIG. 14C, the fixing was performed so that the normal line N and the rotation axis R coincided with each other. As the fixing means, a double-sided tape manufactured by Lion Office Equipment Co., Ltd. (product number, GW-350) and an adhesive putty manufactured by Lion Office Equipment Co., Ltd. (product number: QG-10) were used. The point g shown in FIG.
G. FIG. Fig. 18 by marker (model: FG-102RM)
It was determined as shown in (a). The measurement of the moment of inertia is
Compliant with the operation manual prepared by Inertia Dynamics. The measurement was performed three times, and the average value of the three measurements was used as the measured value. (2) Flying distance evaluation test Five golfers with a head speed of around 35 m / s, five golfers with a head speed of around 40 m / s, and five golfers with a head speed of around 45 m / s,
A flight distance evaluation test was performed. Each golfer hit five golf clubs at a time, and measured the flight distance. The average of the flight distances of all 15 golfers was defined as the flight distance of each golf club. That is, for each golf club, the average of the flight distances of 5 (number of golfers hitting) × 15 (number of golfers) = 75 balls was obtained. This flight distance (m) is 10
The results are shown in Table 1 together with an index value of 0.

[0044]

[Table 1] As can be seen from Table 1, the golf clubs of Examples 1 to 20 had a longer flight distance than the conventional examples and Comparative Examples 1 and 2.

[0045]

As described above, according to the present invention, in the golf club having the head at the tip of the shaft, when the sole position of the head is brought into contact with the reference surface to take the address position, Since the height of the leading edge from the reference plane is 10 mm or more, it is possible to achieve both a low center of gravity of the head and an increase in the moment of inertia.

Therefore, it is possible to increase the effective hitting distance by lowering the center of gravity of the head and to enlarge the sweet area by increasing the moment of inertia of the head. Further, in a golf club having the same moment of inertia, the center of gravity can be lowered to a level that cannot be achieved by the conventional structure, and the flight distance can be greatly increased.

[Brief description of the drawings]

FIG. 1 is a side view showing a periphery of a head of a through-the-green golf club according to an embodiment of the present invention.

2A and 2B are diagrams for explaining an address position, wherein FIG. 2A is a front view of a head, and FIG. 2B is a plan view of the head.

FIG. 3 is a side view of a head for explaining an original loft angle.

4A and 4B are diagrams for explaining a relationship between an original loft angle and an effective hitting distance, wherein FIG. 4A is a side view of a head having a large original loft angle, and FIG. 4B is a side view of a head having a small original loft angle. is there.

FIG. 5 is a side view of the head for explaining a real loft angle.

FIG. 6 is a side view of the head for explaining an original loft angle and a real loft angle.

FIG. 7 is a plan view of the head for explaining the orientation of the face surface when the leading edge is a curve.

FIG. 8 is a side view of the head for explaining an original loft angle when the sole surface is a curved surface.

FIG. 9 is a side view of the head for explaining an original loft angle when the face surface is a curved surface.

FIG. 10 is a side view of the periphery of the head of the golf club for explaining the definition of the club length.

FIG. 11 is a side view of the periphery of the grip of the golf club for explaining the definition of the club length.

FIG. 12 is a perspective view showing an example of a moment of inertia measuring device.

13A and 13B show a method of measuring the moment of inertia, wherein FIG. 13A is a side view of a jig, and FIG. 13B is a side view of a state where a head is placed on the jig.

14A and 14B show a method of positioning the head in measuring the moment of inertia, wherein FIG. 14A is a side view of the head mounted on a jig, FIG. 14B is a side view of the jig, and FIG. It is a side view in the state where the head was mounted.

FIG. 15 is a front view of the head showing a support position when measuring a moment of inertia.

FIG. 16 is a perspective view showing a center-of-gravity measuring device of the head.

FIG. 17 is a side view showing a method of measuring the center of gravity of the head, in a state where the head is placed on the center of gravity measuring device.

18A and 18B show a method of measuring the center of gravity of a head, wherein FIG. 18A is a side view showing a state in which the head is placed at a position where the head is balanced with respect to the center of gravity measuring device, and FIG. It is a side view in the state where it was put in the position which does not become necessary.

FIG. 19 is a side view showing a method of checking the horizontality of the support portion of the center of gravity measuring device, in a state where the level is placed on the center of gravity measuring device.

FIG. 20 is a side view showing a state where the jig is mounted on the moment of inertia measuring device.

FIG. 21 is a side view showing a state where a head is placed on an inertia moment measuring instrument via an adhesive.

[Explanation of symbols]

 Reference Signs List 1 head 2 face surface 3 sole surface 4 shaft 5 leading edge B reference surface H height S shaft axis θo original loft angle θr real loft angle La, Lb Effective hitting distance

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiko Miyamoto 2-1 Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd. Inside the Hiratsuka Factory (72) Inventor Norihiko Nakahara 2-1 Oiwake, Hiratsuka-shi, Kanagawa Yokohama Rubber Co., Ltd. Inside the Hiratsuka Factory (72) Inventor Masaki Akie 2-1 Oiwake, Hiratsuka-shi, Kanagawa Prefecture Yokohama Rubber Co., Ltd. F-term in the Hiratsuka Factory (reference) 2C002 AA02 SS04

Claims (3)

[Claims] 1. A golf club having a head at a tip end portion of a shaft, wherein when a sole surface of the head is brought into contact with a reference surface to take an address position, a height of a leading edge of the head from the reference surface is increased. Saga 10m
m for through-the-green golf clubs. 2. An original loft angle of the head is 8
2. The golf club for through-the-green according to claim 1, wherein an angle difference obtained by subtracting the original loft angle from the real loft angle is 1 degree or less. 3. The golf for the through the green according to claim 1, wherein the moment of inertia of the head measured around an axis passing through the center of gravity of the head and perpendicular to the face surface is 2000 g · cm ² or more. club.