Dimple patterns for golf balls
09795833 · 2017-10-24
Assignee
Inventors
Cpc classification
A63B37/0021
HUMAN NECESSITIES
International classification
Abstract
The present invention provides a method for arranging dimples on a golf ball surface in which the dimples are arranged in a pattern derived from at least one irregular domain generated from a regular or non-regular polyhedron. The method includes choosing control points of a polyhedron, generating an irregular domain based on those control points, packing the irregular domain with dimples, and tessellating the irregular domain to cover the surface of the golf ball. The control points include the center of a polyhedral face, a vertex of the polyhedron, a midpoint or other point on an edge of the polyhedron and others. The method ensures that the symmetry of the underlying polyhedron is preserved while minimizing or eliminating great circles due to parting lines.
Claims
1. A golf ball having an outer surface comprising a plurality of dimples disposed thereon, wherein the dimples are arranged in multiple copies of a first domain and a second domain, the first domain and the second domain being tessellated to cover the outer surface of the golf ball in a uniform pattern having no great circles and consisting of eight first domains and six second domains, and wherein: the first domain has three-way rotational symmetry about the central point of the first domain; the second domain has four-way rotational symmetry about the central point of the second domain; the dimple pattern within the first domain is different from the dimple pattern within the second domain; the number of different dimple diameters on the outer surface, D, is related to the total number of dimples on the outer surface, N, such that if N<350, then D>5; and if N≧350, then D>6; the plurality of dimples consists of a plurality of perimeter dimples and a plurality of interior dimples, wherein each of the plurality of perimeter dimples is located directly adjacent to a border segment of the first domain or a border segment of the second domain, and wherein each of the plurality of perimeter dimples has at least two nearest neighbor dimples that are located in a domain other than the domain of that perimeter dimple; and the difference in diameter between each perimeter dimple and each of its nearest neighbor dimples that is located in a domain other than the domain of that perimeter dimple is 0.08 inches or less.
2. The golf ball of claim 1, wherein each of the dimples has a dimple diameter of from about 0.050 inches to about 0.250 inches.
3. The golf ball of claim 1, wherein all nearest neighbor dimples are separated by substantially the same distance, δ, wherein the average of all δ values is from 0.002 inches to 0.020 inches, and wherein any individual δ value does not vary from the mean by more than 0.005 inches.
4. The golf ball of claim 1, wherein the golf ball has an aerodynamic coefficient magnitude of from 0.25 to 0.32 and an aerodynamic force angle of from 30° to 38° at a Reynolds Number of 230000 and a spin ratio of 0.085.
5. The golf ball of claim 1, wherein the golf ball has an aerodynamic coefficient magnitude of from 0.26 to 0.33 and an aerodynamic force angle of from 32° to 40° at a Reynolds Number of 180000 and a spin ratio of 0.101.
6. The golf ball of claim 1, wherein the golf ball has an aerodynamic coefficient magnitude of from 0.27 to 0.37 and an aerodynamic force angle of from 35° to 44° at a Reynolds Number of 133000 and a spin ratio of 0.133.
7. The golf ball of claim 1, wherein the golf ball has an aerodynamic coefficient magnitude of from 0.32 to 0.45 and an aerodynamic force angle of from 39° to 45° at a Reynolds Number of 89000 and a spin ratio of 0.183.
8. The golf ball of claim 1, wherein a majority of the dimples on the outer surface of the golf ball have a circular plan shape.
9. The golf ball of claim 1, wherein a majority of the dimples on the outer surface of the golf ball have a non-circular plan shape.
10. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 350.
11. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 336.
12. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 360.
13. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 384.
14. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 390.
15. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 320.
16. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 302.
17. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 432.
18. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 342.
19. The golf ball of claim 1, wherein the total number of dimples on the outer surface is 306.
20. The golf ball of claim 1, wherein the difference in diameter between each perimeter dimple and each of its nearest neighbor dimples that is located in a domain other than the domain of that perimeter dimple is 0.06 inches or less.
21. The golf ball of claim 1, wherein the difference in diameter between each perimeter dimple and each of its nearest neighbor dimples that is located in a domain other than the domain of that perimeter dimple is 0.04 inches or less.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the various views:
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DETAILED DESCRIPTION
(17) The present invention provides a method for arranging dimples on a golf ball surface in a pattern derived from at least one irregular domain generated from a regular or non-regular polyhedron. The method includes choosing control points of a polyhedron, connecting the control points with a non-straight sketch line, patterning the sketch line in a first manner to generate an irregular domain, optionally patterning the sketch line in a second manner to create an additional irregular domain, packing the irregular domain(s) with dimples, and tessellating the irregular domain(s) to cover the surface of the golf ball in a uniform pattern. The control points include the center of a polyhedral face, a vertex of the polyhedron, a midpoint or other point on an edge of the polyhedron, and others. The method ensures that the symmetry of the underlying polyhedron is preserved while minimizing or eliminating great circles due to parting lines from the molding process.
(18) In a particular embodiment, illustrated in
(19) For purposes of the present invention, the term “irregular domains” refers to domains wherein at least one, and preferably all, of the segments defining the borders of the domain is not a straight line.
(20) The irregular domains can be defined through the use of any one of the exemplary methods described herein. Each method produces one or more unique domains based on circumscribing a sphere with the vertices of a regular polyhedron. The vertices of the circumscribed sphere based on the vertices of the corresponding polyhedron with origin (0,0,0) are defined below in Table 1.
(21) TABLE-US-00001 TABLE 1 Vertices of Circumscribed Sphere based on Corresponding Polyhedron Vertices Type of Polyhedron Vertices Tetrahedron (+1, +1, +1); (−1, −1, +1); (−1, +1, −1); (+1, −1, −1) Cube (±1, ±1, ±1) Octahedron (±1, 0, 0); (0, ±1, 0); (0, 0, ±1) Dodecahedron (±1, ±1, ±1); (0, ±1/φ, ±φ); (±1/φ, ±φ, 0); (±φ, 0, ±1/φ)* Icosahedron (0, ±1, ±φ); (±1, ±φ, 0); (±φ, 0, ±1)* *φ = (1 + √5)/2
(22) Each method has a unique set of rules which are followed for the domain to be symmetrically patterned on the surface of the golf ball. Each method is defined by the combination of at least two control points. These control points, which are taken from one or more faces of a regular or non-regular polyhedron, consist of at least three different types: the center C of a polyhedron face; a vertex V of a face of a regular polyhedron; and the midpoint M of an edge of a face of the polyhedron.
(23) 1. Center to midpoint (C.fwdarw.M);
(24) 2. Center to center (C.fwdarw.C);
(25) 3. Center to vertex (C.fwdarw.V);
(26) 4. Midpoint to midpoint (M.fwdarw.M);
(27) 5. Midpoint to Vertex (M.fwdarw.V); and
(28) 6. Vertex to Vertex (V.fwdarw.V).
(29) While each method differs in its particulars, they all follow the same basic scheme. First, a non-linear sketch line is drawn connecting the two control points. This sketch line may have any shape, including, but not limited, to an arc, a spline, two or more straight or arcuate lines or curves, or a combination thereof. Second, the sketch line is patterned in a method specific manner to create a domain, as discussed below. Third, when necessary, the sketch line is patterned in a second fashion to create a second domain.
(30) While the basic scheme is consistent for each of the six methods, each method preferably follows different steps in order to generate the domains from a sketch line between the two control points, as described below with reference to each of the methods individually.
(31) The Center to Vertex Method
(32) Referring again to
(33) When domain 14 is tessellated to cover the surface of golf ball 10, as shown in
(34) TABLE-US-00002 TABLE 2 Domains Resulting From Use of Specific Polyhedra When Using the Center to Vertex Method Type of Number of Number of Number of Polyhedron Faces, P.sub.F Edges, P.sub.E Domains 14 Tetrahedron 4 3 6 Cube 6 4 12 Octahedron 8 3 12 Dodecahedron 12 5 30 Icosahedron 20 3 30
The Center to Midpoint Method
(35) Referring to
(36) When domain 14 is tessellated around a golf ball 10 to cover the surface of golf ball 10, as shown in
(37) TABLE-US-00003 TABLE 3 Domains Resulting From Use of Specific Polyhedra When Using the Center to Midpoint Method Type of Number of Number of Polyhedron Vertices, P.sub.V Domains 14 Tetrahedron 4 4 Cube 8 8 Octahedron 6 6 Dodecahedron 20 20 Icosahedron 12 12
The Center to Center Method
(38) Referring to
(39) 1. A regular polyhedron is chosen (
(40) 2. Two adjacent faces 16a and 16b of the regular polyhedron are chosen, as shown in
(41) 3. Center C.sub.1 of face 16a, and center C.sub.2 of face 16b are connected with a segment 18; 4. A copy 20 of segment 18 is rotated 180 degrees about the midpoint M between centers C.sub.1 and C.sub.2, such that copy 20 also connects center C.sub.1 with center C.sub.2, as shown in
(42) When first domain 14a and second domain 14b are tessellated to cover the surface of golf ball 10, as shown in
(43) TABLE-US-00004 TABLE 4 Domains Resulting From Use of Specific Polyhedra When Using the Center to Center Method Number of Number of Number of First Number of Number of Second Type of Vertices, Domains Faces, Edges, Domains Polyhedron P.sub.V 14a P.sub.F P.sub.E 14b Tetrahedron 4 6 4 3 4 Cube 8 12 6 4 8 Octahedron 6 9 8 3 6 Dodeca- 20 30 12 5 20 hedron Icosahedron 12 18 20 3 12
The Midpoint to Midpoint Method
(44) Referring to
(45) When first domain 14a and second domain 14b are tessellated to cover the surface of golf ball 10, as shown in
(46) In a particular aspect of the embodiment shown in
(47) TABLE-US-00005 TABLE 5 Domains Resulting From Use of Specific Polyhedra When Using the Midpoint to Midpoint Method Number of Number of Number of First Number of Second Type of Faces, Domains Vertices, Domains Polyhedron P.sub.F 14a P.sub.V 14b Tetrahedron 4 4 4 4 Cube 6 6 8 8 Octahedron 8 8 6 6 Dodecahedron 12 12 20 20 Icosahedron 20 20 12 12
The Midpoint to Vertex Method
(48) Referring to
(49) When domain 14 is tessellated to cover the surface of golf ball 10, as shown in
(50) TABLE-US-00006 TABLE 6 Domains Resulting From Use of Specific Polyhedra When Using the Midpoint to Vertex Method Type of Number of Number of Polyhedron Faces, P.sub.F Domains 14 Tetrahedron 4 4 Cube 6 6 Octahedron 8 8 Dodecahedron 12 12 Icosahedron 20 20
The Vertex to Vertex Method
(51) Referring to
(52) When first domain 14a and second domain 14b are tessellated to cover the surface of golf ball 10, as shown in
(53) TABLE-US-00007 TABLE 7 Domains Resulting From Use of Specific Polyhedra When Using the Vertex to Vertex Method Number of Number of Number of First Number of Second Type of Faces, Domains Edges per Face, Domains Polyhedron P.sub.F 14a P.sub.E 14b Tetrahedron 4 4 3 6 Cube 6 6 4 12 Octahedron 8 8 3 12 Dodecahedron 12 12 5 30 Icosahedron 20 20 3 30
(54) While the six methods previously described each make use of two control points, it is possible to create irregular domains based on more than two control points. For example, three, or even more, control points may be used. The use of additional control points allows for potentially different shapes for irregular domains. An exemplary method using a midpoint M, a center C and a vertex V as three control points for creating one irregular domain is described below.
(55) The Midpoint to Center to Vertex Method
(56) Referring to
(57) When domain 14 is tessellated to cover the surface of golf ball 10, as shown in
(58) TABLE-US-00008 TABLE 8 Domains Resulting From Use of Specific Polyhedra When Using the Midpoint to Center to Vertex Method Type of Number of Number of Number of Polyhedron Faces, P.sub.F Edges, P.sub.E Domains 14 Tetrahedron 4 3 12 Cube 6 4 24 Octahedron 8 3 24 Dodecahedron 12 5 60 Icosahedron 20 3 60
(59) While the methods described previously provide a framework for the use of center C, vertex V, and midpoint M as the only control points, other control points are useable. For example, a control point may be any point P on an edge E of the chosen polyhedron face. When this type of control point is used, additional types of domains may be generated, though the mechanism for creating the irregular domain(s) may be different. An exemplary method, using a center C and a point P on an edge, for creating one such irregular domain is described below.
(60) The Center to Edge Method
(61) Referring to
(62) When domain 14 is tessellated to cover the surface of golf ball 10, as shown in
(63) TABLE-US-00009 TABLE 9 Domains Resulting From Use of Specific Polyhedra When Using the Center to Edge Method Type of Number of Number of Number of Polyhedron Faces, P.sub.F Edges, P.sub.E Domains 14 Tetrahedron 4 3 6 Cube 6 4 12 Octahedron 8 3 12 Dodecahedron 12 5 30 Icosahedron 20 3 30
(64) Though each of the above described methods has been explained with reference to regular polyhedrons, they may also be used with certain non-regular polyhedrons, such as Archimedean Solids, Catalan Solids, or others. The methods used to derive the irregular domains will generally require some modification in order to account for the non-regular face shapes of the non-regular solids. An exemplary method for use with a Catalan Solid, specifically a rhombic dodecahedron, is described below.
(65) A Vertex to Vertex Method for a Rhombic Dodecahedron
(66) Referring to
(67) When domain 14 is tessellated to cover the surface of golf ball 10, as shown in
(68) After the irregular domain(s) are created using any of the above methods, the domain(s) may be packed with dimples in order to be usable in creating golf ball 10.
(69) In
(70) As in
(71) In a particular embodiment, as illustrated in
(72) In one embodiment, there are no limitations on how the dimples are packed. In another embodiment, the dimples are packed such that no dimple intersects a line segment. In the embodiment shown in
(73) In a particular embodiment, the dimples are packed such that all nearest neighbor dimples are separated by substantially the same distance, δ, wherein the average of all δ values is from 0.002 inches to 0.020 inches, and wherein any individual δ value can vary from the mean by ±0.005 inches. For purposes of the present invention, nearest neighbor dimples are determined according to the following method. Two tangency lines are drawn from the center of a first dimple to a potential nearest neighbor dimple. A line segment is then drawn connecting the center of the first dimple to the center of the potential nearest neighbor dimple. If the two tangency lines and the line segment do not intersect any other dimple edges, then those dimples are considered to be nearest neighbors. For example, as shown in
(74) Each dimple typically has a diameter of from about 0.050 inches to about 0.250 inches. The diameter of a dimple having a non-circular plan shape is defined by its equivalent diameter, d.sub.e, which calculated as:
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where A is the plan shape area of the dimple. Diameter measurements are determined on finished golf balls according to
(76) In a particular embodiment, all of the dimples on the outer surface of the ball have the same diameter. It should be understood that “same diameter” dimples includes dimples on a finished ball having respective diameters that differ by less than 0.005 inches due to manufacturing variances.
(77) In another particular embodiment, there are two or more different dimple diameters on the outer surface of the ball. In a particular aspect of this embodiment, the number of different dimple diameters, D, on the outer surface is related to the total number of dimples, N, on the outer surface, such that if: if N<350, then D>5; and if N≧350, then D>6.
In a further particular aspect of this embodiment, the dimples are arranged in multiple copies of a first domain and a second domain formed according to the midpoint to midpoint method based on an octahedron wherein the first domain and the second domain are tessellated to cover the outer surface of the golf ball in a uniform pattern having no great circles. The overall dimple pattern consists of eight first domains having three-way rotational symmetry about the central point of the first domain and six second domains having four-way symmetry about the central point of the second domain. The dimple pattern within the first domain is different from the dimple pattern within the second domain. Each of the first domain and the second domain consists of perimeter dimples and interior dimples. The dimples optionally have one or more of the following additional characteristics: a) each of the perimeter dimples has at least two nearest neighbor dimples that are located in a domain other than the domain of that perimeter dimple; b) for each perimeter dimple, the difference in diameter between the perimeter dimple and each of its nearest neighbor dimples located in a different domain is 0.08 inches or less, or 0.06 inches or less, or 0.04 inches or less; and c) at least one perimeter dimple in each domain is a same diameter dimple with respect to at least one of its nearest neighbor dimples located in a different domain.
(78) It should be understood that manufacturing variances are to be taken into account when determining the number of different dimple diameters. The placement of the dimple in the overall pattern should also be taken into account. Specifically, dimples located in the same location within the multiple copies of the domain(s) that are tessellated to form the dimple pattern are assumed to be same diameter dimples, unless they have a difference in diameter of 0.005 inches or greater.
(79) For purposes of the present disclosure, each dimple on the outer surface of the golf ball is either a perimeter dimple or an interior dimple and is positioned entirely within a single domain. Perimeter dimples are those dimples located directly adjacent to a border segment. The perimeter dimples of a given domain are those located inside of that domain, and, in a particular embodiment, form an axially symmetric pattern about the geometric center of the domain. Interior dimples are those dimples not located directly adjacent to a border segment. The interior dimples of a given domain are those located within the domain, and, in a particular embodiment, form an axially symmetric pattern about the geometric center of the domain.
(80) For example, in the embodiment shown in
(81) In the embodiment shown in
(82) There are no limitations to the dimple shapes or profiles selected to pack the domains. Though the present invention includes substantially circular dimples in one embodiment, dimples or protrusions (brambles) having any desired characteristics and/or properties may be used. For example, in one embodiment the dimples may have a variety of shapes and sizes including different depths and perimeters. In particular, the dimples may be concave hemispheres, or they may be triangular, square, hexagonal, catenary, polygonal or any other shape known to those skilled in the art. They may also have straight, curved, or sloped edges or sides. To summarize, any type of dimple or protrusion (bramble) known to those skilled in the art may be used with the present invention. The dimples may all fit within each domain, as seen in
(83) In other embodiments, the domains may not be packed with dimples, and the borders of the irregular domains may instead comprise ridges or channels. In golf balls having this type of irregular domain, the one or more domains or sets of domains preferably overlap to increase surface coverage of the channels. Alternatively, the borders of the irregular domains may comprise ridges or channels and the domains are packed with dimples.
(84) When the domain(s) is patterned onto the surface of a golf ball, the arrangement of the domains dictated by their shape and the underlying polyhedron ensures that the resulting golf ball has a high order of symmetry, equaling or exceeding 12. The order of symmetry of a golf ball produced using the method of the current invention will depend on the regular or non-regular polygon on which the irregular domain is based. The order and type of symmetry for golf balls produced based on the five regular polyhedra are listed below in Table 10.
(85) TABLE-US-00010 TABLE 10 Symmetry of Golf Ball of the Present Invention as a Function of Polyhedron Type of Polyhedron Type of Symmetry Symmetrical Order Tetrahedron Chiral Tetrahedral Symmetry 12 Cube Chiral Octahedral Symmetry 24 Octahedron Chiral Octahedral Symmetry 24 Dodecahedron Chiral Icosahedral Symmetry 60 Icosahedron Chiral Icosahedral Symmetry 60
(86) These high orders of symmetry have several benefits, including more even dimple distribution, the potential for higher packing efficiency, and improved means to mask the ball parting line. Further, dimple patterns generated in this manner may have improved flight stability and symmetry as a result of the higher degrees of symmetry.
(87) In other embodiments, the irregular domains do not completely cover the surface of the ball, and there are open spaces between domains that may or may not be filled with dimples. This allows dissymmetry to be incorporated into the ball.
(88) Dimple patterns of the present invention are particularly suitable for packing dimples on seamless golf balls. Seamless golf balls and methods of producing such are further disclosed, for example, in U.S. Pat. Nos. 6,849,007 and 7,422,529, the entire disclosures of which are hereby incorporated herein by reference.
(89) In a particular aspect of the embodiments disclosed herein, golf balls of the present invention have a total number of dimples, N, on the outer surface thereof, of 302 or 306 or 320 or 336 or 342 or 350 or 360 or 384 or 390 or 432.
(90) Aerodynamic characteristics of golf balls of the present invention can be described by aerodynamic coefficient magnitude and aerodynamic force angle. Based on a dimple pattern generated according to the present invention, in one embodiment, the golf ball achieves an aerodynamic coefficient magnitude of from 0.25 to 0.32 and an aerodynamic force angle of from 30° to 38° at a Reynolds Number of 230000 and a spin ratio of 0.085. Based on a dimple pattern generated according to the present invention, in another embodiment, the golf ball achieves an aerodynamic coefficient magnitude of from 0.26 to 0.33 and an aerodynamic force angle of from 32° to 40° at a Reynolds Number of 180000 and a spin ratio of 0.101. Based on a dimple pattern generated according to the present invention, in another embodiment, the golf ball achieves an aerodynamic coefficient magnitude of from 0.27 to 0.37 and an aerodynamic force angle of from 35° to 44° at a Reynolds Number of 133000 and a spin ratio of 0.133. Based on a dimple pattern generated according to the present invention, in another embodiment, the golf ball achieves an aerodynamic coefficient magnitude of from 0.32 to 0.45 and an aerodynamic force angle of from 39° to 45° at a Reynolds Number of 89000 and a spin ratio of 0.183. For purposes of the present disclosure, aerodynamic coefficient magnitude (C.sub.mag) is defined by C.sub.mag=(C.sub.L.sup.2+C.sub.D.sup.2).sup.1/2 and aerodynamic force angle (C.sub.angle) is defined by C.sub.angle=tan.sup.−1 (C.sub.L/C.sub.D), where C.sub.L is a lift coefficient and C.sub.D is a drag coefficient. Aerodynamic characteristics of a golf ball, including aerodynamic coefficient magnitude and aerodynamic force angle, are disclosed, for example, in U.S. Pat. No. 6,729,976 to Bissonnette et al., the entire disclosure of which is hereby incorporated herein by reference. Aerodynamic coefficient magnitude and aerodynamic force angle values are calculated using the average lift and drag values obtained when 30 balls are tested in a random orientation. Reynolds number is an average value for the test and can vary by plus or minus 3%. Spin ratio is an average value for the test and can vary by plus or minus 5%.
(91) When numerical lower limits and numerical upper limits are set forth herein, it is contemplated that any combination of these values may be used.
(92) All patents, publications, test procedures, and other references cited herein, including priority documents, are fully incorporated by reference to the extent such disclosure is not inconsistent with this invention and for all jurisdictions in which such incorporation is permitted.
(93) While the illustrative embodiments of the invention have been described with particularity, it will be understood that various other modifications will be apparent to and can be readily made by those of ordinary skill in the art without departing from the spirit and scope of the invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the examples and descriptions set forth herein, but rather that the claims be construed as encompassing all of the features of patentable novelty which reside in the present invention, including all features which would be treated as equivalents thereof by those of ordinary skill in the art to which the invention pertains.