JP2001269426A - Golf club - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club by which the direction of the face surface can be grasped under an addressed state when a golfer actually hits a ball, and the ball can be hit as is. SOLUTION: A head 1 is provided at the tip end of a shaft, and the loft angle α of the face surface of the head 1 is 15 deg. or higher for this golf club. In such a golf club, on the upper surface 3 which crosses the face surface 2, a drawn line 6 as a direction-recognizing means, which includes a line segment 5 extending in the normal line direction of the face surface 2, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club having a golf club head provided with a direction recognizing means for recognizing a direction of a face surface.

[0002]

2. Description of the Related Art In golf, it is important to hit a ball accurately in a target direction. Therefore, it is important for the golfer to improve the accuracy and repetition of the swing in order to make the ball fly in the target direction accurately, and to properly face the golf ball in the target direction in a state where the golf club is held, that is, in a so-called address state. It is important to turn to However, since a golf club has a lie angle and a loft angle, it is difficult to grasp the correct direction of the face surface in an address state.

That is, since the golf club has a lie angle θ as shown in FIG. 12A and a loft angle α as shown in FIG. 12B, the face surface and the shaft axis are not parallel to each other. . If the face surface and the shaft axis do not become parallel in this way, as shown in FIGS. 13A and 13B, the angle θ ₁ between the horizontal plane and the shaft axis in the address state changes, thereby changing the face surface. The direction changes.

[0004] This phenomenon will be explained in an easy-to-understand manner with a simple model. As shown in FIGS. 14A and 14C, a cylinder having an end face 21 orthogonal to the axial direction,
(B) and (d) rotate the cylinder having the inclined end face 22 in the circumferential direction. Then, it turns out that the direction of the normal does not change when the end face 21 is rotated, but the direction of the normal changes when the end face 22 is rotated.
These rotation of the cylinder corresponds to the change in the angle theta ₁ between a horizontal plane and the shaft axis in the golf club, the inclination angle alpha ₁ of the end face 22 corresponds to the loft angle. That is, end face 2
Second orientation corresponds to the orientation of the face of a golf club having a loft angle α _1. Incidentally, the end face 21 is a case where the loft angle is 0 degrees.

Considering FIGS. 14B and 14D, the larger the angle α ₁ , the greater the change in the orientation of the end face 22 due to rotation, ie, the larger the movement of the normal to the end face 22. It turns out to be. When this is applied to a golf club, it can be said that a golf club having a larger loft angle α has a larger change in the orientation of the face surface due to a change in the angle θ ₁ formed between the horizontal plane and the shaft axis.

[0006] Now, the golfer works in the state of the address.
Angle θ between the horizontal plane and the axis of the shaft₁Is a golfer
It depends on the individual differences. For example, as shown in FIG.
So that the angle θ in the address state₁Golf clubs have
Golfer making the lie angle larger than the lie angle to be made, FIG. 15 (b)
As shown in the figure, the golf club
The golfer dressing, as shown in FIG.
Angle θ in dress state ₁Lie angle of golf club
There are various types of golfers, such as golfers who make them smaller than degrees. In addition, here
The "lie angle of the golf club" described in the
The round of the sole part of the golf club is
To make uniform contact evenly in the toe-heel direction.
To taste.

[0007] In order for a golfer to hit a ball accurately in a target direction, it is necessary to direct the face surface in a correct direction in an address state. As shown in FIG. 15B, if the golf club is set up at the lie angle of the golf club, the score line 23 provides a clue to the orientation of the face surface, but as shown in FIGS. 15A and 15C. If the address is not the same as the lie angle of the golf club, the score line 23 does not serve as a clue for the orientation of the face, and there is no other clue for the orientation of the face.

It may be assumed that a typical golfer uses a golf club that can be addressed as shown in FIG. However, in practice, most golfers use golf clubs that can be addressed as in FIG. 15 (c). The reason is that there is a difference between the angle addressed by the golfer and the angle at the time of hitting, that is, the angle at impact.

FIG. 16A shows a golfer playing a golf club.
FIG. 16B shows the same golf ball.
Fur at impact at the same golf club
Is shown. Golf by centrifugal force during swing
Unravel the angle of the wrist of the golfer, toe down the golf club
Phenomenon (the center of gravity of the golf club head is on the shaft axis)
Because the shaft is not
Deflected, more specifically the toe side of the golf club head is downward
FIG.
Angle θ in the address state shown in FIG.₁FIG. 16
Angle θ at impact shown in (b)_TwoIs bigger
You. By the way, in a general golfer, the angle θ ₁More corners
Degree θ_TwoIs larger by about 5 to 15 degrees.

The golfer or the golf maker or the like considers that it is more important to hit the golf club at the impact state than at the address state according to the lie angle of the golf club rather than at the address state. Golf clubs that can be addressed as in (1) have become common. However, this does not mean that every golfer has selected a golf club having a lie angle that always matches the angle at the time of impact, but merely shows a general tendency.

[0011] Even the same golfer does not always hit the ball from a flat place on the golf course.
For example, in a flat place as shown in FIG.
A so-called toe-rise location as shown in FIG.
The angle θ ₁ in the golfer's address state changes due to a change in inclination such as a so-called toe-down position as shown in FIG.

As described above, a golfer is in a state where he can grasp the clue of the orientation of the face surface only when the golf club is addressed to the horizontal plane at the lie angle, but such a situation is rather rare. In most cases, the golf club cannot be addressed at the lie angle with respect to the horizontal plane. Moreover,
Golfers were forced to change the address angle significantly due to the change in the slope of the ground. Therefore, it can be seen that it is very difficult to orient the face surface in the correct direction in the address state, and it requires skill.

[0013] For the sake of convenience, the improvement of the golf game is indicated in stages. The first stage is to fly from a flat place (practice range) to the target direction, and the second stage is to jump from various slopes (courses) to the target. It is conceivable to fly it in the direction you want. It is difficult to learn even in the first stage,
Even if the first stage is cleared to some extent, the second stage is also difficult to learn, and some golfers will hit the ball from a flat place such as a driving range toward the target, Many golfers are referred to as so-called "practice range singles" who cannot fly to the target at all. From the above, it can be considered that, in the improvement of the golf game, it is necessary not only to acquire the swing (improvement in accuracy and repeatability) but also to increase the accuracy in turning the face in the correct direction.

Conventionally, as a training tool for directing the face surface in a correct direction in an addressed state, Japanese Utility Model Application Laid-Open No. 2-8
No. 8676 and Japanese Utility Model Laid-Open No. 5-68580. In these training tools, the direction of the face surface is correctly grasped by attaching a pointing rod perpendicular to the face surface. However, it is impossible to hit the ball with the indicator rod attached,
Although it could be used to practice the orientation of the face in the address state, it could not be used to actually hit the ball.

In such a case, it may be considered that it is only necessary to attach to the state of the address and remove it immediately before hitting the ball. However, in a golf game that is an individual competition,
It is practically impossible to remove the pointing rod by itself after setting the address state, except to release the address state. In addition, in the address state, the ball is located immediately before the face surface, and the pointing rod is in the way, and the address cannot be performed.

In such a case, it may be thought that it is sufficient to address the ball by attaching a pointing rod to a position where the ball is not normally hit, such as the toe side or the heel side of the face, and hit the ball as it is. If you hit the ball, it would obviously violate the golf rules. Furthermore,
If the ball is hit with the pointing rod or the like attached, there is a danger that the pointing rod will come off with the force of the hit ball, or the ball will be hit with the pointing rod after the core is removed.

From the above, it has been difficult to attach the conventional practice tool at the time of hitting a ball on an actual golf course. In addition, even if the orientation of the face surface is grasped by practicing assuming various inclinations in the state of the address by attaching the conventional training equipment, the inclination is different for each scene in an actual golf course, Considering that you can only hit the ball once from a specific inclination unless you pay a penalty, you can grasp the direction of the face surface for each actual golf course scene, and you can hit the ball in that state Golf clubs were desired.

[0018]

SUMMARY OF THE INVENTION An object of the present invention is to provide a golf club capable of grasping the orientation of the face surface in the state of an address in a scene where a golfer actually hits a ball and hitting the ball as it is. To provide.

[0019]

According to the present invention, there is provided a golf club having a head at a tip portion of a shaft, wherein a loft angle of a face surface of the head is 15 degrees or more. A direction recognition means including a line segment extending in a normal direction of the face surface is provided on an upper surface of the head intersecting with the face surface.

The present inventors have considered that what can always grasp the direction of the face surface even if the angle of the golfer's attitude changes is a line segment perpendicular to the face surface.
By forming the direction recognizing means including this line segment on the upper surface of the head, it is possible to easily grasp the direction of the face surface based on the direction of the line segment in the address state and hit the ball as it is.

That is, in the prior art, the face surface was oriented in the correct direction by learning the sense of direction, but in the present invention, by providing the face surface direction recognizing means on the upper surface of the head, it is not necessary to learn the sense of direction. The face can be oriented in the right direction.

In the present invention, the length of the line segment is preferably 3 mm or more in order to ensure sufficient recognition of the direction of the face surface. As the direction recognition means, a drawing line, a bent portion, a ridge or a groove can be formed. Here, the drawing line means a planar one drawn so as to form a visually recognizable line segment, and the bent portion means a one bent so as to form a visually recognizable line segment. And the ridge means what protrudes from the plane so as to form a visually recognizable line segment, and the groove means what is depressed from the plane so as to form a visually recognizable line segment. . In particular, it is preferable that the direction recognizing means including the drawing line, the bent portion, the ridge or the groove has a plurality of parallel line segments. Further, it is preferable that the width of the band portion sandwiched between the line segments is 10 mm or less, and that the ratio of the width to the length of the band portion is 1.0 or less.

[0023]

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

FIGS. 1A to 1C show a golf club according to a first embodiment of the present invention. This golf club has a head 1 at a tip end of a shaft, and a loft angle α of a face surface 2 with respect to a shaft axis of the head 1 is 15 degrees or more. Face surface 2 of head 1
Β _{1 at} which the head intersects with the head upper surface 3 is substantially a right angle. The head upper surface 3 is provided with a drawing line 6 as a direction recognizing means including a line segment 5 which is substantially perpendicular to the leading edge 4 and extends in the normal direction of the face surface 2. However, the drawing line 6 coincides with the line segment 5 when the line width is sufficiently narrow. It is sufficient that at least one such line segment 5 exists on the head upper surface 3.

According to the golf club described above, the golfer senses a change in the direction of the face surface 2 due to a change in the address angle by visually observing the area around the line segment 5 on the head upper surface 3, and moves the head 1 around the shaft axis. The direction of the face surface 2 can be appropriately corrected while rotating, and the face surface 2 can be oriented in a correct direction.

However, the correct direction does not necessarily mean the target direction. That is, since the determination of the target direction is finally determined by the golfer, there are variations that occur in each scene. Also, due to the golfer's personal habits such as swing, the target direction and the direction of the face surface may not always match depending on the golfer. In other words, most golfers have a habit of striking in the target direction with their face facing right or left in the target direction.

Also, due to the line of sight at the address, the lie angle and the loft angle of the golf club, the line segment visible from the line of sight of the golfer at the address does not necessarily indicate the target direction. For example, the line segment may vary depending on the loft angle. You will be pointing diagonally above. For these reasons, it is not possible for all golfers to always face the face correctly in the target direction, and it is not optimal for all golfers to face the face correctly in the target direction. . That is, in the present invention, the inclination state of the line segment that changes with the change in the orientation of the face surface is used as a judgment material, and the orientation of the face surface can be adjusted as much as possible to the direction that the golfer believes to be correct. .

According to the present invention, there is no clue for recognizing the direction of the face surface except in the case where the face surface is held at the lie angle with respect to the horizontal plane. By providing a direction recognizing means including a line segment extending in the normal direction on the upper surface of the head, the direction of the face surface can be easily grasped even in various states such as inclination of the ground. In other words, it is possible to reduce the illusion of the orientation of the face surface due to the structure of the golf club and the illusion of the orientation of the face surface caused by the change of the angle of the address due to the slope or the like, and thus to enhance the directionality of the hit ball. It becomes possible.

The reason why the loft angle is set to 15 degrees or more in the present invention is that, as described above, a golf club having a larger loft angle causes a larger change in the direction of the face surface due to a change in the angle of the golfer's address. The upper limit of the loft angle is not particularly limited.
However, there is a limit to the loft angle based on the performance and rules of the golf club, and the maximum loft angle is currently 6
It is about 5 degrees.

In the present invention, the line segment needs to extend in the normal direction of the face surface, and the normal direction is a direction perpendicular or substantially perpendicular to the face surface.
More specifically, the angle between the line segment and the face surface is 88
It is necessary that the angle be in the range of -92 degrees. If the angle between the line segment and the face surface is less than 88 or more than 92 degrees, it becomes meaningless as a means for recognizing the target direction.

Here, a comparative example of the present invention will be exemplified. In FIG. 2 (a) ~ (c) , the angle beta ₂ in which the face surface 2 and the head top surface 3 of the head 1 crosses is larger, for example, 10 degrees or more than a right angle. The head upper surface 3 is provided with a line segment 5 substantially perpendicular to the leading edge 4. However, the line segment 5 does not extend in the normal direction of the face surface 2. Since such a line segment 5 does not change with a change in the direction of the face surface 2, it does not function as a means for recognizing the target direction.

FIG. 3 shows the dimension of a line segment in the present invention. As shown in FIG. 3, the length A of the line segment 5 provided on the head upper surface 3 is 3 mm or more. If the length of the line segment is less than 3 mm, it is difficult to recognize the direction of the face surface. The upper limit of the length of the line segment is not particularly limited. This is due to the limitation of the head width based on the design or rule of the golf club.

The line segment according to the present invention may have a slight fluctuation width as long as it can be visually recognized straight. As a numerical range, the ratio of the line segment deflection width (mm) to the line segment length (mm) is 0.01 or less. If this ratio exceeds 0.01, it will be difficult to recognize a straight line, and the meaning as a means for recognizing the target direction will be weakened.

Considering the figure, assuming a cylindrical shape having a length X and a diameter 0.01X as shown in FIG.
If the line segment S passes through an arbitrary point X1 in 3 and extends to an arbitrary point X2 in the lower surface portion 14 without protruding from the side surface portion 15, it can be visually judged that the line segment is straight. By the way, in FIG. 4, if the line segment S undulates inside the cylinder, it may seem that the line S cannot be visually recognized straight, but this is due to the diameter of the cylindrical surface in FIG. Is larger than the length of the cylinder.

In FIG. 3, a linear gauge 12 is applied to the head upper surface 3 so that the length A of the line segment is 3 mm or more, and the swing width B of the line segment is (B / A) ≦ 0.01. If the relationship is satisfied, the present invention functions as a means for recognizing the target direction in the present invention.

FIG. 5 shows a golf club according to a second embodiment of the present invention. This golf club has a face surface 2 and a head upper surface 3, and the face surface 2 and the head upper surface 3 intersect at a substantially right angle. This head upper surface 3
Has many line segments 5 extending in the normal direction of the face surface 2.
Is formed. The golfer perceives a change in the orientation of the face surface 2 due to a change in the address angle by visually observing the hairline composed of a large number of line segments 5 on the head upper surface 3, and rotates the head 1 around the shaft axis. Correct the orientation as appropriate,
The face surface 2 can be oriented in the correct direction. Such a hairline composed of many line segments 5 is suitable for recognizing the direction of the face surface 2.

The hairline is formed mainly by polishing and machining, and is also called a polished eye, a satin eye or the like as another name. The hairline formed by polishing is usually formed with sandpaper coarser than # 600, that is, smaller than # 600, and is preferably # 80 to # 3.
It is formed by 20 sandpapers. Even with sandpaper finer than # 600, that is, larger in number than # 600, a hairline is substantially formed, but it becomes difficult to visually recognize the line segment.

The visually recognizable line segment in the present invention is not limited to a hairline formed by polishing or machining, but may be a line segment formed by marking, painting, surface treatment, or the like.
Boundaries formed by chemical treatment and the like are also visually recognized as line segments.

FIG. 6 shows a golf club according to a third embodiment of the present invention. This golf club has a face surface 2 and a head upper surface 3, and has a bent portion 7 that forms a line segment 5 extending in the normal direction of the face surface 2 on the head upper surface 3. The golfer senses the change in the direction of the face surface 2 due to the change in the address angle by visually observing the line segment 5 of the bent portion 7 of the head upper surface 3, and changes the direction of the face surface 2 while rotating the head 1 around the shaft axis. With appropriate correction, the face surface 2 can be oriented in the correct direction.
The bent portion 7 including the line segment 5 is suitable for recognizing the direction of the face surface 2.

FIG. 7 shows a golf club according to a fourth embodiment of the present invention. This golf club has a face surface 2 and a head upper surface 3, and the face surface 2 and the head upper surface 3 intersect at a substantially right angle. This head upper surface 3
Includes a plurality of line segments 5 extending in the normal direction of the face surface 2.
Is formed. The golfer senses a change in the direction of the face surface 2 due to a change in the address angle by visually observing the ridges 8 including the plurality of line segments 5 on the upper surface 3 of the head, and rotates the head 1 around the shaft axis while rotating the head 1 around the shaft axis. 2, the face 2 can be oriented in a correct direction. The protrusion 8 including the plurality of line segments 5 is suitable for recognizing the direction of the face surface 2.

FIG. 8 shows a golf club according to a fifth embodiment of the present invention. This golf club has a face surface 2 and a head upper surface 3, and the face surface 2 and the head upper surface 3 intersect at a substantially right angle. This head upper surface 3
Includes a plurality of line segments 5 extending in the normal direction of the face surface 2.
Is formed in the groove 9 having a rectangular cross section. The golfer senses a change in the direction of the face surface 2 due to a change in the address angle by visually observing the groove 9 including the plurality of line segments 5 on the upper surface 3 of the head, and rotates the head 1 around the shaft axis while rotating the head 1 around the shaft axis. Can be appropriately corrected, and the face surface 2 can be oriented in the correct direction. Thus, the groove 9 including the plurality of line segments 5 is suitable for recognizing the direction of the face surface 2.

As shown in FIG. 9, for example, as shown in FIG. 9, the line segment 5a located on the upper side of the heel side of the ridge 8 and the line segment located on the upper side of the toe side are included. 5b, a line segment 5c located on the lower side of the heel side, and a line segment 5d located on the lower side of the toe side. However, it is an essential condition that a line segment that functions effectively in the present invention can be recognized from the state of the address. In the case of the ridge 8 having a rectangular cross-sectional shape as shown in FIG. 9, the line segment 5d located on the lower side of the toe side usually does not function as the direction recognition means because it cannot be seen from the golfer's address state. The cross-sectional shapes of the ridges and grooves are not limited to rectangles as shown in the figure, but are triangular, rhombic, trapezoidal,
Other polygons may be used. Further, the cross-sectional shape may change along the length direction of the line segment.

In the present invention, it is preferable that the direction recognizing means composed of a drawing line, a bent portion, a ridge or a groove has a plurality of parallel line segments. That is, by forming a band portion sandwiched between these line segments, the orientation of the face surface can be further easily recognized. However, adjacent line segments need not be strictly parallel, and there is no particular problem if the angle between both line segments is 1 degree or less. When the width of the band portion sandwiched between the two parallel line segments is set to 10 mm or less and the ratio of the width to the length of the band portion is set to 1.0 or less, the aggregate of the line segments is more easily recognized. Since the band is formed, it is more preferable to recognize the direction of the face surface.

FIG. 10 shows a golf club according to a sixth embodiment of the present invention. This golf club has a face surface 2
And a head upper surface 3, wherein the head upper surface 3 is a face surface 2
Extending in the normal direction. Therefore, the head upper surface 3 includes at least a line segment 5 extending in the normal direction of the face surface 2. As described above, the head upper surface 3 itself including the line segment 5 which cannot be visually recognized but extends in the normal direction of the face surface 2 also functions as the direction recognition means. That is, the face surface 2
Since the shape of the head upper surface 3 including the line segment 5 extending in the normal direction changes in accordance with the angle of the address, the golfer can feel the change in the direction of the face surface 2 by looking at the head upper surface 3.

[0045]

EXAMPLES The golf clubs of Examples 1 to 7 based on the present invention and the golf club of the conventional example were manufactured, and an evaluation test of directionality was performed. Hereinafter, the evaluation test will be described in detail. For the golf club group having a used golf club loft angle of 28 degrees and the golf club group having a loft angle of 48 degrees, the following golf clubs of Examples 1 to 7 and a conventional example were prepared.
For each group, the golf club characteristics such as the center of gravity of the golf club head, the swing balance of the golf club, the total weight, the frequency, and the like are the same in Examples 1 to 7 and the conventional example. That is, the same group is the same except for the configuration of the head upper surface of the first to seventh embodiments and the conventional example. Table 1 shows the golf club characteristics of each group.

[0046]

[Table 1]

Conventional Example A conventional golf club, which does not have a line segment extending in the normal direction of the face surface on the upper surface of the head. Example 1 The golf club shown in FIG. 6 has a face surface 2 and a head upper surface 3, and has a bent portion 7 that forms a line segment 5 extending in the normal direction of the face surface 2 on the head upper surface 3. The length of the line segment is 2 mm. Example 2 The golf club shown in FIG. 10 has a face surface 2 and a head upper surface 3, and the head upper surface 3 extends in a direction normal to the face surface 2. Although a line segment cannot be recognized on the head upper surface 3, the length of the head upper surface 3 in the normal direction of the face surface 2 is 10 mm. Example 3 The golf club shown in FIG. 5 has a face surface 2 and a head upper surface 3, and a hairline composed of a number of line segments 5 extending in the normal direction of the face surface 2 is formed on the head upper surface 3. . The hairline was formed by polishing with # 180 sandpaper. The length of the line segment constituting the hairline is 10 mm. Example 4 The golf club shown in FIG. 6 has a face surface 2 and a head upper surface 3, and has a bent portion 7 that forms a line segment 5 extending in the normal direction of the face surface 2 on the head upper surface 3. The length of the line segment is 10 mm. EXAMPLE 5 The golf club shown in FIG. 8 has a face surface 2 and a head upper surface 3, and a groove 9 including a plurality of line segments 5 extending in the normal direction of the face surface 2 is formed in the head upper surface 3. I have.
The length of the line segment is 10 mm. EXAMPLE 6 The golf club shown in FIG. 7 has a face surface 2 and a head upper surface 3, and a ridge 8 including a plurality of line segments 5 extending in the normal direction of the face surface 2 is formed on the head upper surface 3. ing. The length of the line segment is 10 mm. Further, the width of the band portion sandwiched between the line segments is 12 mm. Example 7 The golf club shown in FIG. 7 has a face 2 and a head upper surface 3, and a ridge 8 including a plurality of line segments 5 extending in the normal direction of the face 2 is formed on the head upper surface 3. ing. The length of the line segment is 10 mm. The width of the band portion sandwiched between the line segments is 2 mm.

Evaluation Method of Directivity In order to confirm the improvement of the directivity by the golf club of the present invention, a hit ball test was conducted. In the hit ball test, for each golf club in the group, the direction of the hit ball was determined from five different types of inclinations by a total of eight players, each of two types having different abilities (handy caps) and four members of different heights in the same handicap. Was tested. That is, the first embodiment
A golfer having two kinds of handicaps and four kinds of heights evaluates the directionality of the two kinds of golf club groups consisting of Example 7 and the conventional example by five kinds of inclinations. The selection of the golfer and the selection of the inclination are as follows.

Choice of golfer (handy cap
Separately) The golfers (1) and (2) were selected for each handicap. (1) Golfer around handy cap 15 (2) Golfer around handy cap 5

Selection of Golfers (By Height) With respect to the golfers of (1) and (2 ) above, one golf player (A) to (D ) was selected for each height. (A) Golfer of height 165 to 170cm (A) Golfer of height 170 to 175cm (C) Golfer of height 175 to 180cm (D) Golfer of height 180 to 185cm

Selection of inclination Five types of inclinations (A) to (E) were selected for each inclination. (A) Toe drop 10 degree slope (B) Toe drop 5 degree slope (C) Flat slope (D) Toe rise 5 degree slope (E) Toe rise 10 degree slope

Hitting test (setting of average flight distance D) A hitting test is performed under the above conditions. As shown in FIG. 11, a flat ground that can measure the flight distance on the vertical axis and the horizontal deflection on the horizontal axis is used for the hit ball test. Before the hit ball test, each golfer moves 10 times from the hitting point E to the target point E '.
Hit the ball and measure the average flight distance. The average flight distance in this case is the average of the distance that a golf ball hit from the hitting point first reaches the ground, and is measured on the vertical axis. If the player moves right and left, even if the same flight distance (numerical value on the vertical axis) is recorded, it becomes a hypotenuse, and the recorded flight distance is different from the actual flight distance. Also,
If the right and left blur exceeds 8 m, it is not adopted as data.

Hitting test (method of scoring) As described above, the average flight distance of each golfer is determined, D is set, and a hitting test is performed to score. In FIG. 11, each golfer hits a ball from a hitting point E toward a target point E ′. In the scoring method, 1 to 5 points are evaluated according to the place where the golf ball hit from the hitting point first reaches the ground. In other words, as shown in FIG. 11, 5 points are given in the case of a blur of 2 m or less from the target direction to the left and right, and 4 points are given in the case of more than 2 m and 4 m or less, and 1 point is given in the case of a shake exceeding 8 m in the left and right direction. And Also, ± 20 of the average flight distance (D)
%, That is, data out of the range from 0.8D to 1.2D is not adopted. This is because these data are so-called miss shots, and because there are many causes for the golfer's ability, it is considered that it is not appropriate to adopt the data.

Hitting Test (Order of Hitting) The order of hitting is as follows. Each golfer hits the ball from one of five types of slopes that can be scored by a group of golf clubs. When the test hits at the five types of inclinations are completed, the test hits at the other five types of the golf clubs are similarly performed. As for the order of the inclination, the ball is hit in the order of 10 toes down, 5 toes down, flat, 5 toes up, and 10 toes up. Regarding the order of the golf clubs, the golf ball is hit in the order of the conventional example, the first embodiment, the second embodiment, the third embodiment, the fourth embodiment, the fifth embodiment, the sixth embodiment, and the seventh embodiment. After the group golf clubs have been hit, the group golf clubs are hit in the same manner.

For example, a handy cap (1)
A golfer having a height of (a) evaluates one ball that can be scored for the group of conventional golf clubs in the order of inclinations (A) to (E), and then similarly evaluates the golf club of Example 1. Then, the evaluation is made up to Example 7, and subsequently, the same evaluation is made for the group of golf clubs. Each golfer performs the above evaluation in one day, and performs the same evaluation for 10 days.

Hitting Ball Test (Method of Tallying Scores ) Example 1 consisting of two golf club groups (group, group)
-For a total of 16 golf clubs of Example 7 and the conventional example, the total points of four golfers composed of (a) to (d) of the handicap (1) and ( 4) Consisting of (a) to (d)
Aggregate the total points of human golfers. A golf club group with a handicap (1) scored and totaled is referred to as a total point 1, and a golf club group with a handicap (1) golfer scored and totaled is referred to as a total point 2. The total score obtained by scoring the groups by the handicap (2) golfer was designated as a total score 3, and the total score obtained by scoring the golf club groups by the handicap (2) golfer was designated as the total score 4. Incidentally, the highest point (full score) of each total point is 5 (the highest score) × 4 (the number of golfers) × 5 (the type of inclination) × 10 (the number of days) = 1000 points. Table 2 shows the results of the total scores of the golf club scores.

[0057]

[Table 2]

According to Table 2, when the total points 1 and 2 and the total points 3 and 4 are compared, the total points of the group golf clubs are higher than the total points of the group golf clubs. This is generally natural because a group of golf clubs (a loft angle of 48 degrees) has better directionality in terms of performance of a golf club than a group of golf clubs (a loft angle of 28 degrees). However, the flight distance of the group of golf clubs is larger.

Comparing the total point 1 with the total point 3 and the total point 2 with the total point 4, the total point of the golfer of the handicap (2) is higher than the total point of the golfer of the handicap (1). I understand. This is generally natural because golfers with a handicap (2) are more advanced than golfers with a handicap (1) and show a more directional result in the same golf club hitting test. is there.

Therefore, in order to confirm the effects of the present invention, the results of golfers having the same handicap between golf clubs of the same group should be compared. According to this, in all of the four types of results shown in the tabulation points 1 to 4, it is understood that each of the tabulation points of Examples 1 to 7 is higher than each of the tabulation points of the conventional example. In other words, the golf club according to the present invention is found to have a remarkable improvement in the directionality of the hit ball when comprehensively evaluated from the type of golfer and all inclinations.

[0061]

As described above, according to the present invention, in a golf club having a head at the tip of a shaft and a loft angle of the face of the head being 15 degrees or more, the upper surface of the head intersecting the face Provided with direction recognition means including a line segment extending in the normal direction of the face surface, regardless of the individual differences of golfers or the angle of the address that changes due to various inclinations that golfers encounter at the golf course, the face surface Direction can be easily grasped, and the directionality of the hit ball can be improved.

[Brief description of the drawings]

FIG. 1 shows a golf club head according to a first embodiment of the present invention, wherein (a) is a perspective view, (b) is a top view,
(C) is a side view.

2A and 2B show a golf club head according to a comparative example of the present invention, wherein FIG. 2A is a perspective view, FIG. 2B is a top view, and FIG. 2C is a side view.

FIG. 3 is a sectional view showing a line segment provided on an upper portion of a head of the golf club of the present invention.

FIG. 4 is an explanatory diagram showing a line segment in the present invention.

FIG. 5 is a perspective view showing a golf club head according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing a golf club head according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing a golf club head according to a fourth embodiment of the present invention.

FIG. 8 is a perspective view showing a golf club head according to a fifth embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a ridge provided on an upper portion of a head of the golf club of the present invention.

FIG. 10 is a perspective view showing a golf club head according to a sixth embodiment of the present invention.

FIG. 11 is a bird's-eye view of a ground for performing a hit ball test.

FIGS. 12A and 12B are diagrams showing a lie angle and a loft angle of a golf club.

FIGS. 13A and 13B are diagrams showing a change in an angle between a shaft axis of a golf club and a horizontal plane.

FIGS. 14A to 14D are diagrams showing, as a model, a change in the direction of the face surface due to a change in the angle formed between the shaft axis of the golf club and the horizontal plane.

FIGS. 15A to 15C are views showing golf clubs in different address states of a golfer.

FIGS. 16A and 16B are diagrams showing golf clubs in a golfer's address state and impact state.

FIGS. 17 (a) to (c) are diagrams illustrating a change in an angle between a shaft axis of a golf club and a horizontal plane due to a change in inclination.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Head 2 Face surface 3 Head upper surface 4 Leading edge 5 Line segment 6 Drawing line 7 Bending part 8 Ridge 9 Groove α Loft angle

Claims (5)

[Claims] 1. A golf club in which a head is provided at a tip portion of a shaft, and a loft angle of a face surface of the head is 15 degrees or more, in a direction normal to the face surface, the head upper surface intersecting the face surface. A golf club provided with direction recognizing means including an extended line segment. 2. The golf club according to claim 1, wherein the length of the line segment is 3 mm or more. 3. The golf club according to claim 1, wherein the direction recognizing means comprises a drawing line, a bent portion, a ridge, or a groove. 4. The golf club according to claim 3, wherein the direction recognizing means comprising the drawing line, the bent portion, the ridge, or the groove has a plurality of parallel line segments. 5. The width of a band portion sandwiched between the line segments is 10 mm.
And the ratio of the width to the length of the band is 1.
The golf club according to claim 4, wherein the value is 0 or less.