JP4582357B2 - Golf ball - Google Patents

Description

  The present invention relates to a golf ball having excellent flight characteristics.

It is well known that in golf balls, in order to obtain a great flight distance, it is important to have high resilience provided in the ball itself and to reduce air resistance during flight by dimples arranged on the surface of the ball. In order to reduce the air resistance, various methods for arranging the dimples on the entire ball surface as densely and as uniformly as possible have been proposed.
Here, the shape of the dimple usually used is a hollow having a circular shape in plan view. In order to arrange such circular dimples with high density, for example, even if the width of the land part that divides two adjacent dimples is reduced to near zero, it is surrounded by three or four of the arranged dimples. In the portion, a land portion as a spherical surface having a certain size such as a triangular shape or a quadrangular shape having a certain area is formed. On the other hand, since it is indispensable to arrange the dimples as evenly as possible on the spherical surface, the arrangement density of the circular dimples must be compromised to some extent.

Under such a background, the dimples are arranged with high density and evenly, and dimples having a diameter different from about 2 to 5 kinds are arranged with the ball spherical surface as a regular octahedron or a regular icosahedron. (For example, refer to Patent Document 1).
However, as long as circular dimples are arranged as described above, it is practically possible to reduce the occupancy ratio of the land area as a spherical surface to the surface area of the golf ball to around 25%. In order to further reduce the air resistance during flight by dimples arranged on the surface of the golf ball, it has been required to further reduce the occupancy of the land area as a spherical surface in the surface area of the golf ball.

JP 2001-212260 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a golf ball having a good flying performance by reducing the occupancy ratio of the land area as a spherical surface occupying the surface area of the golf ball.

  As a result of intensive studies to achieve the above object, the present inventor has found that by forming a smooth surface on the spherical surface of the golf ball, the ratio of the land portion as the spherical surface to the entire golf ball surface can be remarkably reduced. As a result, the inventors have made the present invention.

That is, the present invention provides the following golf balls.
Claim 1:
Both obtained if a 300 to 550 dimples on the spherical surface of the sphere as a base, smooth surface is formed on the dimple outer peripheral edge, and the surface shape such that a portion of the spherical surface of the sphere as the base remains is formed A golf ball characterized by that.
Claim 2:
The golf ball according to claim 1, wherein the smooth surface is a polygonal plane or a circular plane. Claim 3:
The golf ball according to claim 2, wherein dimples are provided inside the polygonal plane or the circular plane.
Claim 4:
The golf ball according to claim 3, wherein dimples are provided in an inner central portion of the polygonal plane or the circular plane.
Claim 5:
The golf ball according to any one of claims 1 to 4, wherein a ratio of an area of the land portion as a spherical surface to a total surface area of the golf ball is less than 20%.
Claim 6:
4. The golf ball according to claim 3, wherein when the dimple has a circular shape, the dimple diameter is 1 to 6 mm.
Claim 7:
4. The golf ball according to claim 3, wherein the maximum distance between the spherical spherical surface and the bottom of the dimple is 0.05 mm or more and 0.4 mm or less.

  According to the present invention, the ratio of the land area as a spherical surface to the total surface area of the golf ball can be made as close to zero as possible, and the dimples are arranged on the golf ball surface as evenly as possible. Is also possible.

  According to the golf ball of the present invention, by providing a smooth surface on the ball surface, the ratio of the land area to the golf ball surface area can be advantageously reduced, and as a result, the air resistance of the hit ball is reduced. In addition, the flight performance of the golf ball can be dramatically increased.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a front view of a golf ball 1 showing an embodiment of the present invention, and FIG. 2 is a partially enlarged view of a central portion of the front view of the golf ball in FIG.
A golf ball 1 according to an embodiment of the present invention is formed by forming a smooth surface or a flat surface extending in a ring shape on a spherical surface. In most regions of the surface of the golf ball 1, a hexagonal area surrounded by six ridge lines 1r each extending linearly forms a hexagonal plane 11, and dimples 1d are provided in this plane. .

In addition to the hexagonal plane shown in FIG. 1, the polygonal plane used in the present invention is a plane of a polygonal shape (preferably a regular polygonal shape) such as a triangular shape, a quadrangular shape or a pentagonal shape, or a combination thereof. Can be used. Circular planes can be used as long as the object of the present invention is not impaired.
Further, as the planar view shape of the dimples formed inside these planes, an elliptical shape, an oval shape, or a polygonal shape (preferably a regular polygonal shape) other than the illustrated circular shape can be used as appropriate. .
In this golf ball 1, dimples 1 d are provided inside all polygonal planes. However, a polygonal plane or a circular plane that does not have dimples is used as a golf ball within a range that does not impair the object of the present invention. You may arrange | position on the surface.

  In the golf ball 1, a point where three ridge lines 1 r that are boundaries between adjacent hexagonal planes 11 intersect, that is, the vertex 1 t shown in FIG. 2 is located at the farthest radial direction or radial direction from the center of the golf ball. To do. Therefore, the edge f of the dimple 1d in the golf ball 1 is not located at the farthest radial direction or radial direction from the center of the golf ball.

In molding the golf ball in the present invention, a two-part mold can be used. The mold has a spherical cavity inside and is provided with a flat surface for molding a smooth surface on the surface of the golf ball and a projection for molding dimples as required on the inner wall surface. is there.
In creating the mold, a hemispherical master mold can be used.
To create this hemispherical master mold, first, a hemispherical body having a large number of flat portions on the surface is created. FIG. 3 is a partially enlarged view showing a configuration example of the hemisphere 2 having a large number of plane portions on the surface.

The hemisphere 2 having a large number of flat portions on the surface is formed by cutting a circular plane with a predetermined radius on the base hemisphere, and six circular planes with the same radius around the circumference are equally spaced. It can be created by cutting and arranging so as to interfere with each other. In this case, a straight ridge line is formed at a position where two adjacent circular planes interfere with each other, and a hexagonal plane portion 21 surrounded by six ridge lines is formed.
In the example shown in FIG. 3, a part of the original spherical surface remains only at the intersection (vertex 2t) where the ridgeline 2r intersects. When the amount of interference between adjacent circular planes is relatively small, the length of the ridgeline 2r is shortened, and a land portion having a relatively wide area near the position corresponding to the vertex 2t is a part of the original spherical surface. Will remain as.

The hemispherical master mold can be created by carving the dimples 2d in the hemispherical body 2 having a large number of plane portions on the surface created as described above. The dimple 2d can be carved inside the flat part 21, but the dimple 2d may be carved out of the other flat part so as to straddle the adjacent flat part. However, by using a lot of such protruding dimples and carving the dimple 2d including the apex 2t position, the outer diameter of the golf ball itself becomes small, and a mold that can only obtain a golf ball that does not conform to the rules of the golf ball is created. There is a risk of resulting in
In order to avoid such a problem, for example, a dimple 2d having a planar view shape that fits in the plane portion 21 can be engraved on the hemisphere 2 with reference to the same coordinates used when the plane portion 21 is formed. Good.

  When the golf ball of the present invention is molded using a two-part mold created based on the hemispherical master mold created as described above, the molded golf ball and the hemispherical master mold are almost identical. It will have a spherical shape.

  In FIG. 2, the ridge line 1 r is a straight line having substantially no width, and the vertex 1 t is also a literal point having substantially no area. However, in forming a golf ball, the hemispherical master mold is near the vertex 2 t position. In the case where a land portion having a relatively large area is used, a spherical surface corresponding to the land portion in the hemispherical master mold is located near the vertex 1t where the three ridge lines 1r intersect. The land part will be formed. The land portion as the spherical surface is formed as a part of the spherical surface (the remainder of the spherical surface) as in the case of the hemispherical master mold, and is the farthest in the radial direction from the center of the golf ball. It is a part located in.

The ratio of the land portion as the spherical surface to the total surface area of the golf ball is usually less than 20%, particularly preferably less than 15%. If the ratio is greater than 20%, air resistance may increase and flight distance may not increase.
1 and 2, when the portion of the apex 1t formed as the intersection of the three ridge lines 1r has no area, the land portion as the spherical surface is The ratio of the area to the total surface area of the golf ball is substantially 0%.

Next, the structural example of AA sectional drawing in FIG. 2 is shown in FIGS. These are schematic sectional views of dimples preferably used in the present invention. The AA line passes through the center of the dimple 1d.
In the example shown in FIG. 4, a ring-shaped hexagonal plane 11 is formed so as to be inclined from the left and right ridgelines 1r, and the dimple 1d having an edge f on the ring-shaped hexagonal plane 11 faces toward the center of the golf ball. It is formed in a convex shape. That is, both the side part s and the bottom part b are formed by the contour by the curve which protruded inside the golf ball.
FIG. 7 shows a partially enlarged sectional view of the vicinity of the ring-shaped hexagonal plane 11. A virtual plane 15 in FIG. 7 is a virtual plane at the hexagonal plane 11 position.

In the example shown in FIG. 5, the side portion s extends relatively steeply from the edge f of the ring-shaped hexagonal plane 11, and is connected to a flat bottom b extending substantially parallel to the ring-shaped hexagonal plane 11. Has dimple characteristics.
The example shown in FIG. 6 is similar to the example of FIG. 5 in that it has side portions s that sharply extend from the position of the edge f toward the bottom b, but the bottom b is a vertex 1t that is an intersection of the ridge lines 1r. It is characterized in that it is formed substantially parallel to or concentric with the outer peripheral line of the phantom spherical surface 12 at the position.

When the dimple shape is circular, the diameter of the dimple based on the position of the edge f is 1 mm or more, preferably 2 mm or more, and the upper limit is 6 mm or less, preferably 5 mm or less.
When the dimple shape is a polygonal shape, the maximum distance between the vertices of the dimples based on the position of the edge f is 1 mm or more, preferably 2 mm or more, and the upper limit is 6 mm or less, preferably 5 mm or less.
Even if these values are larger than the upper limit value or smaller than the lower limit value, the flight distance may decrease.
The maximum distance p between the outer circumference of the phantom spherical surface 12 and the dimple bottom b at the vertex 1t position is 0.05 mm or more, preferably 0.1 mm or more, and the upper limit is 0.4 mm or less, preferably 0.3 mm or less. . Even if the maximum distance p is larger than the upper limit value or smaller than the lower limit value, the flight distance may decrease.

  When arranging a polygonal or circular plane having dimples on the golf ball surface, a spherical icosahedron, dodecahedron, octahedron arrangement, random arrangement, or the like known in relation to the dimple arrangement is appropriately used. be able to. In the embodiment shown in FIG. 1, a configuration including a pentagonal plane P surrounded by five ridge lines and a hexagonal plane Q and R surrounded by six ridge lines, each having a circular dimple at the center. Is shown.

  In FIG. 1, the portions indicated by reference signs X and Y form a pentagonal unit by combining five hexagonal planes Q having dimples around the pentagonal plane P having dimples. Is. Three pentagonal units X are arranged on the same latitude with an interval of 120 ° around the axis 14 passing through the pole 13. Similarly, three pentagonal units Y are arranged on the same latitude line at an interval of 120 ° about the axis 14. Accordingly, six pentagonal units X and Y are arranged in the northern and southern hemispheres divided at the equator e, respectively.

The group of pentagonal unit X and the group of pentagonal unit Y are arranged on substantially the same latitude as in the illustrated example, for example, the group of X is arranged on a relatively high latitude, and the group of Y is relatively low It can be placed on the latitude.
The surface area of the golf ball excluding the pentagonal units X and Y is covered with hexagonal planes having dimples, and six similar hexagonal planes are placed close to each other around one hexagonal plane R. A combined hexagonal unit Z is arranged.

More specifically, in the hexagonal unit Z, the same is achieved by six hexagonal planes surrounding one of the six hexagonal planes other than the hexagonal plane located at the center. A hexagonal unit Z can be formed.
Further, any hexagonal plane except for the pentagonal plane located at the center of the pentagonal units X and Y can correspond to any of the six hexagonal planes surrounding the hexagonal plane located at the center of the hexagonal unit. Is.

  In this embodiment, the total number of flat portions extending in a ring shape around the dimples is 362 including a pentagonal shape and a hexagonal shape.

It is a top view of a golf ball explaining one example of the present invention. It is the elements on larger scale of a golf ball explaining one example of the present invention. It is the elements on larger scale explaining one structural example of the hemispherical master metal mold | die used for preparation of the metal mold | die which shape | molds the golf ball of this invention. It is a schematic sectional drawing explaining the example of 1 structure of the dimple part in the golf ball of this invention. It is a schematic sectional drawing explaining the other structural example of the dimple part in the golf ball of this invention. It is a schematic sectional drawing explaining another structural example of the dimple part in the golf ball of this invention. It is a partial expanded sectional view near the ring-shaped hexagonal plane in the golf ball of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Golf ball 11 Hexagonal plane 12 Virtual spherical surface 13 Pole 14 Axis 15 Virtual plane 2 Hemisphere 21 which has many plane parts on the surface Plane part 1t, 2t Vertex 1d, 2d Dimple 1r, 2r Edge f Edge e Equatorial p Maximum distance b Dimple bottom P Pentagonal plane Q, R Hexagonal plane X, Y Pentagonal unit Z Hexagonal unit

Claims (7)

Both obtained if a 300 to 550 dimples on the spherical surface of the sphere as a base, smooth surface is formed on the dimple outer peripheral edge, and the surface shape such that a portion of the spherical surface of the sphere as the base remains is formed A golf ball characterized by that.   The golf ball according to claim 1, wherein the smooth surface is a polygonal plane or a circular plane.   The golf ball according to claim 2, wherein dimples are provided inside the polygonal plane or the circular plane.   The golf ball according to claim 3, wherein dimples are provided in an inner central portion of the polygonal plane or the circular plane.   The golf ball according to any one of claims 1 to 4, wherein a ratio of an area of the land portion as a spherical surface to a total surface area of the golf ball is less than 20%.   4. The golf ball according to claim 3, wherein when the dimple has a circular shape, the dimple diameter is 1 to 6 mm.   4. The golf ball according to claim 3, wherein the maximum distance between the spherical spherical surface and the bottom of the dimple is 0.05 mm or more and 0.4 mm or less.

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