GB2162760A - Golf ball - Google Patents

Abstract

A golf ball construction comprising a sphere with dimples distributed over the exterior surface. The dimples are located in twenty triangular areas with each area comprising: a) A triangular arrangement of fifteen dimples 14; and, b) Three lines 20 of dimples 16 defining a triangle and forming a border around said triangular arrangement. Each of the lines contains six dimples which are shared with a corresponding line of an adjacent area on the surface. The lines also contain apex dimples 18 at each end with each apex dimple being shared with four other adjacent areas on the surface. The combination results in 492 dimples on the surface. <IMAGE>

Description

SPECIFICATION Golf ball This invention relates to golf balls, in particular to the dimple pattern provided on the exterior surface of the balls.

The use of depressions or indentations (dimples) on golf ball surfaces is well-known. This results from the finding that superior aerodynamic properties are obtained when compared with a smooth exterior surface for the ball. Numerous attempts have been made toward varying the size and depth of the dimples as well as the pattern defined by the dimples on the surface with a view toward obtaining optimum aerodynamic properties and resulting golf ball flight performance. The flight performance is usually described in terms of the distance that a ball will travel after a given impact with a golf club, and also in terms of the variation from the flight path ("hooking" and "slicing").

Generally speaking, it has been considered desirable to achieve a dimple pattern which will provide maximum distance with minimum flight path variation.

British Patent No. 1,415,413 provides one example of efforts made to find optimum dimple patterns for golf balls. This patent suggests the formation of from 122 to 392 dimples on the ball surface with careful attention being given to depth and spatial relationship of the dimples.

U.S. Patent No. 4,142,727 discusses an arrangement for dimples which are of varying sizes and which are arranged in a dodecahedron, icosahedron or octahedron pattern. In this case, the use of up to 480 dimples is proposed.

Other examples of suggestions for dimple patterns are found in U.S. Patent Nos. 4,258,921; 4,090,716 and 4,141,559. The latter disclosure, in particular, discusses the fact that 336 dimples tends to be the average for conventional golf balls but suggests that 252 dimples provides the optimum amount when the patent teachings are otherwise followed.

Summary of the invention This invention involves the discovery that improvements in golf ball performance both with respect to distance and flight deviations can be achieved with a dimple pattern not previously contemplated by the prior art. In particular, the invention is concerned with a golf ball defining an exterior surface having dimples located in twenty triangular areas with these areas evenly distributed over the surface. Each of the triangular areas includes a triangular arrangement of fifteen dimples with this triangular arrangement being surrounded by three lines of dimples defining a triangle and defining a border around the triangular arrangement. Each of these lines contains six dimples which are shared with a corresponding line of an adjacent area on the surface.Each line also includes apex dimples at each end, and these apex dimples are shared with four other adjacent triangular areas on the surface.

The combination of the triangular areas results in the provision of 492 dimples on the golf ball surface. The dimples are preferably of uniform di ameter and depth, and are preferably evenly distributed over the surface. Each of the triangular areas includes a triangular arrangement of fifteen dimples with this triangular arrangement being surrounded by three lines of dimples defining a triangle and forming a border around the triangular arrangement. Each of these lines contains six dimples which are shared with a corresponding line of an adjacent area on the surface. Each line also includes apex dimples at each end, and these apex dimples are shared with four other adjacent triangular areas on the surface.

The combination of the triangular areas results in the provision of 492 dimples on the golf ball surface. The dimples are preferably of uniform diameter and depth, and are preferably evenly distributed over the surface. This configuration achieves a golf ball of substantially improved performance.

Description of the drawings Figure 1 is an elevational view of a golf ball showing triangular areas defined on its exterior surface; and, Figure 2 is a detail view showing the dimple pattern which characterizes two adjacent triangular areas.

Description of the preferred embodiment Figure 1 schematically illustrates a golf ball 10 which may be of any conventional design from the standpoint of its essential structure. Typically, such a golf ball will comprise a two-piece or three-piece construction, and would be produced using injection molding or compression molding techniques.

Dimples formed on the ball in accordance with this invention may also be formed by any conventional technique which would normally involve the utilization of molds having surfaces which will leave the desired dimple pattern in the ball surface upon completion of the molding operation.

The ball 10 is divided into a plurality of distinct areas 12 each comprising a triangle. The invention contemplates 20 such triangular areas which can be achieved by projecting onto the surface of the sphere the edges of an icosahedron. It will be appreciated that lines separating the respective triangular areas do not actually appear on the completed ball, but the illustration of Figure 1 is helpful for purposes of illustrating the concepts of the invention.

Figure 2 illustrates dimple patterns which are formed in two adjacent triangular areas 12. Each dimple pattern consists of fifteen dimples 14 which are collected in a triangular arrangement adjacent the middle of each triangle area. Each of these triangular arrangements is bordered by three lines of dimples with the lines defining a triangle. The respective lines are made up of a group of six dimples 16, and apex dimples 18 at each end of the group of six dimples. A group of six dimples in one of the lines is indicated by the bracket 20 shown in Figure 2. It will be appreciated that the combination of the dimples 16 and 18 provides a triangular border around each group of fifteen dimples 14.

The arrangement of dimples in accordance with the invention can be best understood when comparing Figures 1 and 2. In this connection, each pair of triangular areas in Figure 1 is separated by a line, for example the line 22. This line is shown in Figure 2, and it will be appreciated that the dimples 16 and 18 formed along this line are shared by respective triangular areas 12. Thus, six dimples 16 and the two dimples 18 on opposite sides thereof are positioned along the line 22, and each of these dimples forms part of the dimples of a given triangular area.

An apex dimple 18 is formed at each juncture 24 of triangular areas. It will be noted that five different triangular areas have a jucture at each point and, accordingly, each apex dimple of a triangular area is shared with four other triangular areas.

The result of a configuration of the type illustrated is that 492 dimples are formed on the golf ball surface. Thus, each of the twenty triangular areas includes fifteen dimples 14 making up 300 dimples. Each of the three lines of a triangular area contains six dimples 16 comprising eighteen dimples 16 for each of the twenty areas; but since these are all shared with an adjacent triangular area, a total of 180 dimples is involved. Finally, each of the 20 triangular areas has three apex dimples 18; however, since these are all shared by five triangular areas, twelve apex dimples are actually formed on the surface.

The respective triangular areas, as well as the dimples forming the triangular areas, are preferably evenly distributed over the golf ball surface.

Furthermore, it is preferred that each dimple be of substantially the same size. In the latter connection, the dimples may have a diameter varying from about 2.54 to about 3.429 mm (about 0.1 to about 0.135 inches) and a depth varying from about 0.076 to 0.343 mm (about 0.003 to 0.0135 inches) A suitable configuration involves dimples of about 3.175 mm (about 0.125 inches) in diameter and about 0.1727 mm (about 0.0068 inches) in depth.

The molding processes for golf balls normally result in an "equator" on a golf ball representing the parting line of mold halves. In a typical molding operation, a flash will develop along this line, and this flash will be ground-off prior to painting of the ball. Figures 1 and 2 illustrate an equator seam line at 26 which extends parallel with the rows of dimples, and essentially bisects one triangular area. It will be appreciated, however, that this position of the equator is not a critical feature of the invention.

The particular arrangement of dimples in accordance with this invention provides a substantially perfect symmetry for the dimples. It is believed that this accounts for the excellent performance characteristics of golf balls produced in accordance with this invention.

It will be understood that various changes and modifications may be made in the above-described construction which provide the characteristics of the invention without departing from the spirit thereof particularly as defined in the following

Claims (5)

claims. CLAIMS

1. In a golf ball construction comprising a sphere with dimples distributed over the exterior surface, the improvement wherein said dimples are located in twenty triangular areas substantially evenly distributed over said surface, each triangular area including: a) a triangular arrangement of fifteen dimples; and, b) three lines of dimples defining a triangle and forming a border around said triangular arrangement, each said line containing six dimples which are shared with a corresponding line of an adjacent area on the surface, and apex dimples at each end of each said line, said apex dimples being shared with four other adjacent areas on the surface, the combination of triangular areas providing 492 dimples on the surface.

2. A golf ball according to Claim 1 wherein said dimples are of substantially the same size and are substantially evenly distributed over said surface.

3. A golf ball according to Claim 2 wherein said dimples have a diameter varying from about 2.54 to 3.429 mm (about 0.1 to about 0.135 inches), and have a depth varying from about 0.076 to 0.343 mm (about 0.003 to about 0.0135 inches).

4. A golf ball according to Claim 3 wherein said dimples are about 3.175 mm (about 0.125 inches) in diameter and about 0.1727 mm (about 0.0068 inches) in depth.

5. A golf ball substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.