GB2237210A

GB2237210A - Seamless golf ball

Info

Publication number: GB2237210A
Application number: GB8923780A
Authority: GB
Inventors: Brian Francis Machin
Original assignee: Dunlop Ltd
Current assignee: Dunlop Ltd
Priority date: 1989-10-21
Filing date: 1989-10-21
Publication date: 1991-05-01
Also published as: GB8923780D0; FR2654004A1; JPH03140168A; ZA907476B; AU6246490A; DE4031889A1

Abstract

A golf ball is provided with a plurality of dimples in its spherical outer surface. Any great circle (30) drawn on the surface of the ball intersects and preferably bisects one or more of the dimples. One of the great circles may correspond to the parting line of a mould used to make the golf ball. The dimples may be arranged in a repeating pattern over the whole surface and the pattern may be defined by projecting on to the surface the edges (20) of a regular polyhedron. <IMAGE>

Description

1.

SEAMLESS GOLF BALL This invention relates to a seamless golf ball, i.e. a golf ball having a plurality of dimples in its spherical outer surface, wherein it is not possible to draw on the surface of the ball a great circle which does not intersect at least some of the dimples.

Golf balls are generally made by a moulding process in a two-part mould. Hitherto, all such moulded golf balls have had at least one dimple-free great circle (that great circle corresponding to the parting line of the mould). This, in turn, has led to the need, by golf ball manufacturers, to compromise the symmetry of the pattern of dimples on the golf ball in order to accommodate the dimple-free parting line. Consequently, the number of dimple patterns available (for an acceptable golf ball to be produced) has been limited.

We have now found that it is possible to produce a golf ball in which there are no dimple-free great circles. This leads to the possibility of improved ball symmetry, an increase in the number of possible dimple patterns and optimum use of the ball surface.

Accordingly, the present invention provides a golf ball having a plurality of dimples in its spherical outer surface, in which any great circle drawn on said spherical outer surface intersects any one or more of said dimples.

Preferably, at least one of the great circles substantially bisects any dimple which it intersects and such a great circle substanthally bisecting dimples may, in a preferred embodiment, correspond to the parting line of the mould used to make the golf ball.

The dimples may conveniently be arranged in a repeating pattern over the spherical surface of the ball and the pattern may suitably be determined by projecting on to the spherical surface the edges of a polyhedron.

2.

The polyhedron may be, for example, an icosidodecahedron, a dodecahedron, an icosahedron or a cube.

The dimples may be of arcuate (e.g. circular) plan view or non-arcuate (e. g. rectangular) plan view.

The present invention will be illustrated, merely by way of example, with reference to the accompanying drawings, each of which shows a schematic view of a golf ball according to the invention, wherein any great circle of the ball intersects at least some of the dimples.

In the drawings (wherein like numerals denote like parts) a golf ball 10 is provided with a plurality of dimples, the dimples being arranged in a repeating pattern corresponding to the projection of the edges of a polyhedron on to the surface of the ball. These edges are indicated by chain-dotted lines 20.

A broken line 30 shows, in each of the drawings, one of the many possible great circles of the ball. It will be seen that each great circle intersects at least some of the dimples. Further information relating to the number and shape of the dimples and to the type of Polvhedron used to determine the repeating dimple pattern, is given in the TABLE below.

TABLE

Figure No of Shape of Polyhedron No Dimples Dimples Type 1 630 arcuate icosi-dodecahedron 2 570 arcuate icosi-dodecahedron 3 470 arcuate dodecahedron 4 422 arcuate dodecahedron 370 arcuate icosahedron 6 440 arcuate cube 7 540 non-arcuate dodecahedron 1 Z 4 0

Claims

3. CLAIMS:

A golf ball having a plurality of dimples in its spherical outer surface, in which any great circle drawn on said spherical outer surface intersects any one or more dimples.
2. A golf ball according to Claim 1, in which at least one of said great circles substantially bisects any dimple which it intersects.
3. A golf ball according to Claim 2 and made by a moulding process, in which one of said great circles substantially bisecting dimples corresponds to the parting line of the mould.
4. A golf ball according to Claim 1, 2, or 3, in which said dimples are arranged in a repeating pattern over said spherical outer surface.
5. A golf ball according to Claim 4, in which said repeating pattern is determined by projecting on to said spherical surface the edges of a polyhedron.
6. A golf ball according to Claim 5, in which said polyhedron is a cube.
7. A golf ball according to Claim 5, in which said polyhedron is a dodecahedron.
8. A golf ball according to Claim 5, in which said polyhedron is an icosahedron.
9. A golf ball according to Claim 5, in which said polyhedron is an icosi-dodecahedron.
10. A golf ball according to any one of Claims 1 to 9, in which said dimples are of arcuate plan view.
11. A golf ball according tp any one of Claims 1 to 9, in which said dimples are of non-arcuate plan view.
12. A golf ball, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

WK/CW - ISC GOLF 10557 1 Published 1991 at '17he Patent Office. State House, 66/71 High Holborn. London N%FC I R47?. Further copies may be obtained from Sales Branch. Unit 6, Nine Mile Point. Cwmfelinfach, Cross Keys. Newport, NPI 7HZ. Printed by Multiplex techniques ltd, St Mary Cray, Kent.