JP3061597B2 - Golf club head having face groove - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club head having a unique arrangement of face grooves on the surface.

[0002]

2. Description of the Related Art Conventionally, a marking (groove) pattern or face line on a face surface of a golf club head has been devised to give an effective backspin to a ball to determine the trajectory of a hit ball and secure a flight distance. The technology is known. A typical example of these is
Japanese Patent Application Laid-Open No. 59-164076 discloses a head in which the distance between grooves on the face surface is narrow near the sweet spot and widened in other portions as disclosed in JP-A-59666. A head having no face line at least near the center, as disclosed in Japanese Utility Model Laid-Open No. 25654/1985, the interval between a plurality of concave grooves provided on the face surface is narrowed toward the sole, and the upper direction is reduced. , A head formed sequentially wide in
As disclosed in Japanese Unexamined Patent Application Publication No. 08968, the face surface is divided into a toe-side region, a center region, and a heel-side region,
And a head in which the number of horizontal face lines (score lines) is increased from the toe side area to the heel side area. As disclosed in Japanese Patent Application Laid-Open No. 9-38251, the interval between the markings is lower than the face surface. Head formed so as to gradually increase from the top to the top, and further,
As disclosed in Japanese Patent Application Laid-Open No. 9-47530, there is disclosed a head in which concave score lines and dimples are formed only in the lower part of the face surface and the upper part is formed of a smooth surface.

[0003]

However, the above-mentioned prior arts cannot correct a change in spin caused by a gear effect due to a difference in hit point when hitting a ball with a golf club. That is, as shown in FIG. 1, when the golf club is divided into four parts (up, down, left, and right) around the sweet spot on the face of the golf club, and the spin is applied at each of the hit points, the upper face (A1)
In the case where the hit point is the hit point, the back spin decreases and the hook spin increases because the upward spin and the right spin are applied, and the lower face (A2 face) of the toe side on the face side is formed. When a hit point is reached, a downward spin and a rightward spin are provided, so that the back spin increases and the hook spin increases. On the other hand, when the upper surface (A3 surface) on the heel side of the face becomes the hit point, the back spin decreases and the slice spin increases because the upward spin and the left spin are applied. When the heel side lower surface (A4 surface) is a hit point, a downward spin and a leftward spin are applied, so that the back spin increases and the slice spin increases. Based on such an analysis, it was found that each of the above-described prior arts had a reverse idea to the above-described analysis.

In particular, when the face surface of a golf club and the ball surface are wet due to rain or other causes, a water film is formed between the face surface and the ball surface, and a groove such as a face line is formed. Even if there is, a phenomenon that spin is not given occurs, and it is still in a state where it is not possible to correct a change in spin characteristics and effective spin is not given.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to be used when a golf club hits a ball.
Since the spin of the ball changes with the hit point, the aim is to correct the change and enhance the stability of the trajectory of the hit ball, basically devising the arrangement of the face grooves on the face surface of the golf club, The spacing of linear or dot-like face grooves is increased from the upper surface to the lower surface of the face surface except for the entire surface or a certain region near the sweet spot. A golf club head having a plurality of linear grooves forming face grooves on the face surface so as to gradually widen from above to below the face surface. (2) a golf club head having a plurality of grooves on a face, wherein a groove interval H defined by two vertically adjacent grooves is The grooves are arranged so as to change from the lower side to the lower side, and the change in the interval H between the grooves is such that the interval H between the grooves excluding the uppermost step on the face is equal to or greater than the interval between the grooves one immediately above the interval H between the grooves. A golf club head having a groove having a size, and a groove between the fourth and lower steps from the top is larger than a groove between three grooves above the groove, and (3) a groove in the face A plurality of linear grooves constituting a face groove in the face surface except for a circular portion having a radius of 5 to 15 mm centered on a sweet spot on the face surface, and (4) A golf club head having a groove in the face, characterized in that the golf club head has a groove in the face. Except for a circular portion having a radius of 5 to 15 mm centered on the spot, grooves are arranged such that a gap H defined by two vertically adjacent grooves changes from top to bottom, and a gap H between the grooves is set. The change is that the interval H between the grooves except for the uppermost step on the face is greater than the interval between the grooves one level higher than the distance H between the grooves, and the distance between the grooves at the fourth level or less from the top is three times higher. (5) A golf club head having a groove in a face characterized by being larger than a gap between the grooves, wherein (5) all or a part of the face groove is provided with rows or columns of punch marks. ) ~
A golf club head having a groove in a face according to any one of the above items (4).

[0006]

FIG. 2 is a schematic view of a golf club head having a face groove according to the present invention. On the face surface shown in FIG. 2, a plurality of linear grooves constituting the face grooves are engraved with straight lines intermittent in the horizontal direction (all or a part may be rows or columns of punch marks). . The present invention will be described in a very simple manner in which the interval (pitch) between a plurality of rows of face grooves forming a pair in the vertical direction is gradually increased from the upper side to the lower side of the face surface. To explain this more specifically, a plurality of grooves are provided in the face surface in the vertical direction. When Y grooves are arranged in the vertical direction, the first row extends downward from the first row in the first row. , The second row..., And the lowermost groove is the Y row. Then, an interval H between two vertically adjacent grooves can be determined. In a normal case where the grooves are connected without interruption from the toe to the heel, the interval between the j-th row and the j + 1-th row of the groove is H. (0, j)
Then, H (0,1) ≦ H (0,2) ≦... ≦ H (0,
Y) and the grooves are arranged so as to satisfy H (0, j) <H (0, j + 3). In addition, as shown in FIG. 2, when one groove is not continuous from the toe to the heel and the face surface can be divided into a plurality of regions arranged in the direction from the toe to the heel by a cut in the groove, each region is Is referred to as a row, and the area near the sweet spot is defined as row 0, from row 0 to row 1 in the heel direction,
A row and an order are assigned, and the area closest to the heel is defined as an Xh row. From row 0 to row 1 in the toe direction. An order is set to -2 rows, and an area is set such that the area on the toe side is the -Xt row. From the above, the groove located at the i-th region in the heel direction from column 0 near the sweet spot and in the heel direction, ie, the groove at column i and row j, can be called the groove at column i and row j + 1 The spacing between the grooves in a row is defined as H (i, j). In such a case, in the present invention, in an arbitrary region i row, the interval H between the grooves in the region is equal to the interval H between the lower grooves.
, H (i, 1) ≦ H (i, 2) ≦... ≦ H (i,
Y), and the grooves are arranged so as to satisfy also H (i, j) <H (i, j + 3). In other words, in each case, (A) the interval H between the grooves except for the uppermost step on the face is set to be equal to or greater than the interval between the grooves one immediately above the interval H between the grooves, and (B) The distance H between the fourth and lower grooves from the top can be expressed as a golf club head in which grooves are arranged so as to be larger than the distance three above the distance between the grooves.
The reason why the uppermost row is excluded in the above (A) is that there is no groove interval above the interval H (0, 1) of the uppermost groove to be compared. In ()), the spacing is limited to the fourth and lower grooves only because there is no three-upper gap to be compared.

The above-mentioned plurality of linear grooves are provided in a plurality of columns, preferably 4 to 6 columns, in the horizontal direction in FIG. 2, while a plurality of rows, preferably in pairs, are also formed in the vertical direction. Is 6-8
Row face grooves are provided. Of course, the number of columns and the number of rows described above can be arbitrarily changed from the shape of the golf club head and other characteristics unique to the golf club head.

[0008] This is because the upper half of the face is a hitting point where the spin decreases, so that the interval between the face grooves is gradually narrowed so that the spin is further applied, while the lower half of the face is a hitting point where the spin increases. The spacing between the face grooves is gradually increased and reduced so that unnecessary spin is not applied. Practically, the above-mentioned groove interval is set to be about 3 to 5 mm at the minimum and about 5 to 10 mm at the maximum, and the width may be gradually increased from the upper side to the lower side of the face surface between these numerical values. . Further, between the vertical columns of the face grooves in the X direction, the grooves have the same configuration as the above-described groove intervals, even if the positions of the grooves are slightly different between the vertical columns.

By adopting such a configuration, it is possible to suppress a decrease in the backspin when the upper half of the face becomes a hit point, and to reduce the back spin when the lower half of the face becomes a hit point. Can suppress an increase in backspin. That is, by adopting such a configuration, it is possible to suppress a large change in the backspin amount due to the variation of the hit points, and it is possible to obtain a substantially constant backspin amount regardless of the hit points.

Further, in the present invention, as shown in FIG.
As described above, on the face surface excluding the circular portion of up to 15 mm, (A) the interval H between the grooves excluding the uppermost step on the face has a size equal to or greater than the interval between the grooves one immediately above the interval H between the grooves. And (B) the grooves can be arranged such that the distance H between the fourth and lower grooves from the top is greater than the distance three times higher than the distance between the grooves. The reason for this is that the periphery of the sweet spot (approximately equivalent to a circular portion having a radius of 5 to 15 mm) is always a hit point at which an optimum spin can be obtained, and conversely, the face groove is eliminated so as not to apply unnecessary spin.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. As the specifications of the experimental club, the club length of the present invention and the two types of conventional products (1 and 2) were 44 inches in club length and 1 in loft.
0.5 °, head weight: 190 g, club weight: 300
g, a striking robot made by Tul-Temper with a head speed of 43 m / sec.
Using a superman Dangan two-piece ball manufactured by Maruman, the A1 surface and the A surface shown in FIG.
The groove spacing and the number of grooves at the center, the hit points A, the hit points B, the hit points D, the hit points E, and the hit points C at the sweet spots on the two faces, the A3 face and the A4 face (the groove included in the contact surface between the ball and the face) The number of back spins and the C hitting point ratio (meaning the increase / decrease% of the back spin of each hitting point relative to the hitting point C) at that time are shown in Table 1. Here, the hit points A, B, D, and E
The position of each hit point is 10 mm from a coordinate axis centered on the sweet spot, that is, a horizontal line (X axis).
And a distance of 15 mm from the perpendicular (Y axis).

[0012]

[Table 1]

As can be seen from Table 1, the golf club head according to the present invention has superior properties in terms of the backspin amount and the C hitting ratio as compared with the conventional golf club head.

[0014]

As described above, according to the present invention, the face groove of the golf club head is provided with a face groove which gradually widens from the upper side to the lower side, whereby the golf club head is optimized according to the striking position of the face side. This makes it possible to give a good spin.

[Brief description of the drawings]

FIG. 1 is a diagram showing a hit point position and a spin state on a face surface of a golf club head.

FIG. 2 is a front view of a golf club head provided with a face groove according to the present invention.

FIG. 3 is a front view showing another embodiment of a golf club head provided with a face groove according to the present invention.

FIG. 4 is a diagram showing hit points of an experimental club used in an example of the present invention.

Claims (5)

(57) [Claims] 1. A golf club head having a groove on a face, wherein a plurality of linear grooves constituting a face groove are provided on the face surface so as to gradually increase from above to below the face surface. A golf club head having a groove in a face. 2. A golf club head having a plurality of grooves on a face, wherein grooves are arranged so that a gap H defined by two vertically adjacent grooves changes from above to below. The change in the interval H is such that the interval H between the grooves excluding the uppermost step on the face is equal to or greater than the interval between the grooves one level higher than the interval H between the grooves, and the gap between the fourth and lower steps from the top is the same. A golf club head having a groove in a face that is larger than a gap between three grooves above. 3. A golf club head having a groove on a face, wherein a plurality of linear grooves forming the face groove are formed on the face surface except for a circular portion having a radius of 5 to 15 mm centered on a sweet spot on the face surface. A golf club head having a groove in the face, the groove being provided so as to gradually increase from the upper side to the lower side of the face surface. 4. A golf club head having grooves on a face, wherein a gap H defined by two vertically adjacent grooves is excluded except for a circular portion having a radius of 5 to 15 mm centered on a sweet spot on the face surface. The grooves are arranged so as to change from the upper side to the lower side, and the change in the interval H between the grooves is such that the interval H between the grooves excluding the uppermost step on the face is equal to or greater than the interval between the grooves one immediately above the interval H between the grooves. A golf club head having a groove in a face, the groove having a size being larger than the groove between the fourth and lower steps from the top, the groove being three steps above. 5. The golf club head according to claim 1, wherein all or a part of the face grooves are provided with rows or columns of punch marks.