The present invention relates to golf ball dimple patterns based on a square dipyramid, wherein the dimples are arranged within four substantially identical triangular sections on each of the two hemispheres of the ball.
Golf ball manufacturers make substantial efforts to maximize the aerodynamic efficiency of golf balls, though they are closely controlled by golf's national governing body, the United States Golf Association (U.S.G.A.). One U.S.G.A. requirement is that golf balls have aerodynamic symmetry. Aerodynamic symmetry allows the ball to fly with a very small amount of variation no matter how the golf ball is placed on the tee or ground. In order to improve aerodynamic symmetry, many dimple patterns are based, for example, on geometric shapes, the five Platonic Solids, and the thirteen Archimedean Solids. Because the number of symmetric solid plane systems useful in designing dimple patterns is limited, it can be difficult to devise new symmetric patterns. Moreover, dimple patterns based on some geometric shapes result in less than optimal surface coverage and other disadvantageous dimple arrangements.
Thus, there is a continuing need for novel dimple patterns incorporating unique combinations of dimple properties such as size, shape, number, volume, or arrangement, in order to provide a golf ball that has distinctive characteristics.
The present invention is directed to a golf ball having a plurality of dimples arranged in a pattern defined by a square dipyramid projected on the spherical outer surface of the ball. The plurality of dimples comprises at least three different dimple diameters, including a minimum dimple diameter, a maximum dimple diameter, and at least one additional dimple diameter. The golf ball consists of two hemispheres separated by an equator. The two hemispheres have substantially identical dimple arrangements. Each hemispherical dimple arrangement consists of four triangular sections that are defined by projecting the four faces of a square pyramid onto the hemisphere, such that each of the four triangular sections is defined by a border consisting of a linear equatorial edge which corresponds to a portion of the equator of the ball and two linear side edges connecting each end of the equatorial edge to a pole of the ball. The four triangular sections of each hemisphere are substantially identical in size and dimple arrangement. The dimple arrangement within each of the four triangular sections optionally includes a shared polar dimple having a centroid that lies at the vertex of the two side edges of the section. The diameter of the shared polar dimple, if present, is not the minimum dimple diameter or the maximum dimple diameter. The dimple arrangement within each of the four triangular sections is not rotationally symmetric about the center of the section. Each of the four triangular sections can be divided into a polar region, an intermediate region, and an equatorial region. The polar region is the area of the triangular section from latitude angle 0° to latitude angle 30°, with latitude angle 0° being the pole. The intermediate region is the area of the triangular section from latitude angle 30° to latitude angle 60°. The equatorial region is the area of the triangular section from latitude angle 60° to latitude angle 90°, with latitude angle 90° being the equator.
In a particular embodiment, the polar region includes at least one non-polar dimple having the minimum dimple diameter and does not include a dimple having the maximum dimple diameter. The intermediate region includes at least one dimple having the minimum dimple diameter and at least one dimple having the maximum dimple diameter. The equatorial region includes at least one dimple having the maximum dimple diameter and does not include a dimple having the minimum dimple diameter. In a particular aspect of this embodiment, the intermediate region includes at least one dimple having the minimum dimple diameter. In another particular aspect of this embodiment, the intermediate region includes at least one dimple having the maximum dimple diameter. In another particular aspect of this embodiment, the intermediate region includes at least one dimple having the minimum dimple diameter and at least one dimple having the maximum dimple diameter.
In another particular embodiment, the polar region has a dimple surface coverage Sp, the intermediate region has a dimple surface coverage Si, the equatorial region has a dimple surface coverage Se, and Sp≠Si≠Se.
In another particular embodiment, from 2% to 10% of the dimples have an elliptical plan shape. In a particular aspect of this embodiment, each dimple having an elliptical plan shape is located in the polar region.
In another particular embodiment, a majority of the dimples are spherical dimples having a circular plan shape and a cross-sectional profile defined by a spherical function, the difference in the average edge angle of the spherical dimples present in the polar region and the average edge angle of the spherical dimples present in the intermediate region is greater than 0.25°, the difference in the average edge angle of the spherical dimples present in the intermediate region and the average edge angle of the spherical dimples present in the equatorial region is greater than 0.25°, and the difference in the average edge angle of the spherical dimples present in the polar region and the average edge angle of the spherical dimples present in the equatorial region is greater than 0.25°.
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:
A square pyramid is a polyhedron formed by connecting each of the four vertices of a square base to an apex. The resulting solid consists of the square base and four triangular faces that are equal in size, and has five vertices, including the four vertices of the square base and the apex. Each of the four triangular faces has two side edges and a base edge. Adjacent faces have a common side edge. Thus, a square pyramid has eight linear edges, including four side edges and four base edges.
A square dipyramid is a polyhedron formed from two square pyramids joined at their bases. The resulting solid consists of eight triangular faces that are equal in size, and has six vertices, including four vertices of the base at which the two square pyramids are joined and the apex of each of the two square pyramids. Each of the eight triangular faces has two side edges and a base edge. Adjacent faces on the same side of the square dipyramid have a common side edge, and adjacent faces on opposite sides of the square dipyramid have a common base edge. Thus, a square dipyramid has twelve linear edges, including eight side edges and four base edges.
Golf ball dimple patterns of the present invention are based on a square dipyramid. As shown in
The two hemispheres of the ball have substantially identical dimple arrangements. For purposes of the present disclosure, dimple arrangements are substantially identical if the relative positions of their dimples' centroids are about the same, as would be understood by one of ordinary skill in the art. The overall dimple pattern on the golf ball may have a rotational offset between the two hemispheres of up to 45°.
The dimple arrangement within each of the four triangular dimple sections on each of the two hemispheres of the ball is substantially identical. For purposes of the present disclosure, the triangular section within which a dimple is located is determined based on the location of the centroid of the dimple. Thus, each dimple on the ball is said to be located in a single dimple section, other than dimples having a centroid that is located along a side edge or an equatorial edge.
Dimples having a centroid that is located along an edge are referred to herein as shared dimples. A shared dimple whose centroid lies on a side edge, but does not lie at one of the two apexes of the dipyramid or at one of the four vertices of the base at which the two square pyramids are joined, is referred to herein as a side edge dimple. Thus, side edge dimples are shared between adjacent sections of one hemisphere that have a common side edge on which the centroid of the side edge dimple lies. A shared dimple whose centroid lies on an equatorial edge, but does not lie at one of the four vertices of the base at which the two square pyramids are joined, is referred to herein as a shared equatorial dimple. Thus, shared equatorial dimples are shared between adjacent sections of different hemispheres that have a common equatorial edge on which the centroid of the shared equatorial dimple lies. A shared dimple whose centroid lies at an apex, i.e., a single point shared by the four sections of one hemisphere and corresponding to the pole, is referred to herein as a polar dimple. Thus, polar dimples are shared between the four sections of the hemisphere containing the pole on which the centroid lies. A shared dimple whose centroid lies at one of the four vertices of the base at which the two square pyramids are joined is referred to herein as a base vertex dimple. Thus, base vertex dimples are shared between four sections, including two adjacent sections of one hemisphere that have common equatorial edges with two adjacent sections of the other hemisphere.
Dimples of the present invention are either a shared dimple or a non-shared dimple. Thus, non-shared dimples of the present invention are dimples having a centroid that is not located along an edge. Non-shared dimples of the present invention include dimples having a perimeter that is not intersected by any edge, referred to herein as non-intersected dimples, and dimples having a perimeter that is intersected by an equatorial edge but not a side edge, referred to herein as non-shared equatorial dimples. Dimple patterns of the present invention do not include non-shared dimples having a perimeter that is intersected by a side edge.
The dimple arrangement within each of the triangular sections comprises a plurality of non-intersected dimples, and, optionally, one or more of the following: a polar dimple, one or more side edge dimples, one or more non-shared equatorial dimples, one or more shared equatorial dimples, or one or more base vertex dimples.
In a particular embodiment of the present invention, the dimple arrangement within each of the triangular sections consists of a plurality of non-intersected dimples, at least one side edge dimple, at least one non-shared equatorial dimple, and, optionally, a polar dimple. In a particular aspect of this embodiment, there are no dimple free great circles on the outer surface of the ball. In other words, in this particular aspect, every great circle on the outer surface of the ball intersects at least one dimple.
In another particular embodiment of the present invention, the dimple arrangement within each of the triangular sections consists of a plurality of non-intersected dimples, at least one non-shared equatorial dimple, and, optionally, a polar dimple. In a particular aspect of this embodiment, the triangular section includes a polar dimple, and there are no dimple free great circles on the outer surface of the ball. In another particular aspect of this embodiment, the triangular section does not include a polar dimple, and the outer surface of the ball has two dimple free great circles defined by the side edges of the triangular sections.
In another particular embodiment of the present invention, the dimple arrangement within each of the triangular sections consists of a plurality of non-intersected dimples, at least one side edge dimple, and, optionally, a polar dimple. In a particular aspect of this embodiment, the outer surface of the ball has a dimple free great circle corresponding to the equator.
In another particular embodiment of the present invention, the dimple arrangement within each of the triangular sections consists of a plurality of non-intersected dimples. In a particular aspect of this embodiment, the outer surface of the ball has a dimple free great circle corresponding to the equator and two dimple free great circles defined by the side edges of the triangular sections.
Referring again to
The dimple arrangement within each of the triangular sections is not rotationally symmetric about the center of the section.
Each of the triangular sections can be divided into three regions: a polar region, an intermediate region, and an equatorial region. The polar region is the area of the triangular section from latitude angle 0° to latitude angle 30°. The intermediate region is the area of the triangular section from latitude angle 30° to latitude angle 60°. The equatorial region is the area of the triangular section from latitude angle 60° to latitude angle 90°. Latitude angle 0° is the pole. Latitude angle 90° is the equator. For example,
The region within which a dimple is located is determined based on the location of the centroid of the dimple. For purposes of the present disclosure, dimples having a centroid located at latitude angle 30° are defined as being within the intermediate region, and dimples having a centroid located at latitude angle 60° are defined as being within the equatorial region. As discussed further below, for purposes of calculating the dimple surface coverage of a region, the entire area of the plan shape of a dimple is included in the calculation of the dimple surface coverage of the region in which the centroid of the dimple is located, even though a portion of the dimple may lie in another region. It should also be noted that, in embodiments of the present invention wherein the dimple pattern includes side edge dimples, when calculating the dimple surface coverage for the polar, intermediate, and equatorial regions of a single triangular section, only half of the total plan shape area for each side edge dimple is included in the calculation.
The polar region of each triangular section has a dimple surface coverage Sp, which, for purposes of the present invention, is determined as follows. The surface area of the polar region of each triangular section (if no dimples were present), Ap, is calculated as:
where R is the ball radius
The sum of the plan shape areas of all of the dimples located in (i.e., having centroids located in) the polar region of each triangular section, ADp, is calculated. The dimple surface coverage of the polar region of each triangular section, Sp, is then calculated as:
The intermediate region of each triangular section has a dimple surface coverage Si, which, for purposes of the present invention, is determined as follows. The surface area of the intermediate region of each triangular section (if no dimples were present), Ai, is calculated as:
where R is the ball radius
and Ap is the surface area of the polar region of each triangular section (if no dimples were present), calculated according to the equation above. The sum of the plan shape areas of all of the dimples located in (i.e., having centroids located in) the intermediate region of each triangular section, ADi, is calculated. The dimple surface coverage of the intermediate region of each triangular section, Si, is then calculated as:
The equatorial region of each triangular section has a dimple surface coverage Se, which, for purposes of the present invention, is determined as follows. The surface area of the equatorial region of each triangular section (if no dimples were present), Ae, is calculated as:
where R is the ball radius
and Ap and Ai are the surface area of the polar region of each triangular section (if no dimples were present) and the surface area of the intermediate region of each triangular section (if no dimples were present), respectively, calculated according to the equations above. The sum of the plan shape areas of all of the dimples located in (i.e., having centroids located in) the equatorial region of each triangular section, ADe, is calculated. The dimple surface coverage of the equatorial region of each triangular section, Se, is then calculated as:
In a particular embodiment, dimple patterns of the present invention have one or more of the following properties:
Each triangular section includes at least three different dimple diameters, including a maximum dimple diameter, a minimum dimple diameter, and at least one additional dimple diameter. In a particular embodiment, each triangular section includes at least four different dimple diameters. In another particular embodiment, each triangular section includes at least five different dimple diameters. In another particular embodiment, each triangular section includes at least six different dimple diameters. Preferably, in dimple patterns of the present invention wherein a polar dimple is present, the polar dimple does not have the minimum dimple diameter. It should be understood that manufacturing variances are to be taken into account when determining the number of different dimple diameters. For purposes of the present disclosure, dimples having substantially the same diameter, also referred to herein as “same diameter” dimples, includes dimples on a finished ball having respective diameters that differ by less than 0.005 inches due to manufacturing variances.
In a particular embodiment, dimple patterns of the present invention have one or more of the following properties:
Dimple patterns of the present invention optionally have one or more of the following additional properties:
Dimples of the present invention are not limited to a particular plan shape or profile shape. Particularly suitable plan shapes include, but are not limited to, circular, polygonal, oval, and irregular shapes. Particularly suitable profile shapes include, but are not limited to, circular, catenary, elliptical, and conical shapes.
In a particular embodiment, dimple patterns of the present invention include a plurality of dimples having an elliptical plan shape. Elliptical plan shapes have a major axis and a minor axis, the length of the major axis being greater than the length of the minor axis. The length of the minor axis of elliptical plan shapes of dimples of the present invention is preferably, but not necessarily, from 0.120 inches to 0.160 inches. The difference between the length of the major axis and the length of the minor axis of elliptical plan shapes of dimples of the present invention is preferably, but not necessarily, 0.020 inches or less, or the difference is 0.003 inches or 0.005 inches or 0.020 inches, or the difference is within a range having a lower limit and an upper limit selected from these values. The difference between the length of the major axis and the length of the minor axis of an elliptical plan shape of one dimple may be the same as or different than that of an elliptical plan shape of another dimple. For example, the dimples having an elliptical plan shape may include a first portion of dimples wherein the difference between the length of the major axis and the length of the minor axis is from 0.003 inches to 0.005 inches, and a second portion of dimples wherein the difference between the length of the major axis and the length of the minor axis is from 0.005 inches to 0.020 inches. The ratio of the length of the major axis to the length of the minor axis of elliptical plan shapes of dimples of the present invention is preferably, but not necessarily, from 1.02 to 1.10, or from 1.02 to 1.04, or from 1.04 to 1.10. The ratio of the length of the major axis to the length of the minor axis of an elliptical plan shape of one dimple may be the same as or different than that of an elliptical plan shape of another dimple. For example, the dimples having an elliptical plan shape may include a first portion of dimples wherein the ratio of the length of the major axis to the length of the minor axis is from 1.02 to 1.04, and a second portion of dimples wherein the ratio of the length of the major axis to the length of the minor axis is from 1.04 to 1.10.
In a particular aspect of this embodiment, at least 2%, or from 2% to 10%, or from 4% to 8%, of the dimples have an elliptical plan shape. In a further particular aspect of this embodiment, the remaining dimples consist of dimples having a circular plan shape. In another further particular aspect of this embodiment, the remaining dimples consist of dimples having a non-elliptical, non-circular plan shape. In another further particular aspect of this embodiment, the remaining dimples include a first portion of dimples having a circular plan shape and a second portion of dimples having a non-elliptical, non-circular plan shape.
In another particular aspect of this embodiment, each dimple having an elliptical plan shape is located in the polar region. In a further particular aspect of this embodiment, the polar dimple, if present, has a circular plan shape.
Each dimple on the outer surface of the ball preferably has a diameter of 0.050 or 0.060 or 0.070 or 0.080 or 0.090 or 0.100 or 0.110 or 0.120 or 0.130 or 0.150 or 0.160 or 0.170 or 0.180 or 0.190 or 0.200 or 0.205 or 0.210 or 0.220 or 0.250 inches or a diameter within a range having a lower limit and an upper limit selected from these values. In a particular embodiment, the maximum difference between any two dimple diameters on the ball is less than 0.055 inches. The diameter of a dimple having a non-circular plan shape is defined by its equivalent diameter, de, which calculated as:
where A is the plan shape area of the dimple. By the term, “plan shape area,” it is meant the area based on a planar view of the dimple plan shape, such that the viewing plane is normal to an axis connecting the center of the golf ball to the centroid of the dimple. Diameter measurements are determined on finished golf balls according to
In a particular embodiment, a majority of the dimples on the outer surface of golf balls of the present invention are spherical dimples, i.e., dimples having a circular plan shape and a profile shape based on a spherical function.
In a particular aspect of this embodiment, the spherical dimples have one or more properties/characteristics selected from:
In another particular aspect of this embodiment, the spherical dimples have one or more properties/characteristics selected from.
Preferably, none of the dimples on the outer surface of the ball overlap or touch.
Dimple patterns generated by the present invention are capable of achieving a high percentage of surface coverage. In a particular embodiment, the present invention generates a surface coverage of about 75% or greater. In another particular embodiment, the present invention generates a surface coverage of about 78% or greater.
The total number of dimples on the golf ball is preferably an even number between about 250 and about 500. In a particular embodiment, the total number of dimples is 320 or 322 or 328 or 330 or 336 or 338 or 344 or 346 or 352 or 354 or 360 or 362 or 368 or 370 or the total number of dimples is within a range having a lower limit and an upper limit selected from these values.
Golf balls of the present invention are not limited by a particular golf ball construction. The golf ball may have any type of core, such as solid, liquid, wound, and the like, and may be a one-piece, two-piece, or multilayer ball. Each layer of the golf ball may be constructed from any suitable thermoset or thermoplastic material known to those of ordinary skill in the art. When desirable, the cover may be coated with any number of layers, such as a base coat, top coat, paint, or any other desired coating. As will be appreciated by those skilled in the art, any manufacturing technique may be used to construct the various portions of the golf ball. In a particular embodiment, the golf ball is a multilayer ball comprising a solid, single layer core, an inner cover layer, and an outer cover layer. In a particular aspect of this embodiment, the core is formed from a thermoset rubber, the inner cover layer is formed from an ionomer composition, and the outer cover layer is formed from a polyurethane composition.
The following non-limiting examples demonstrate dimple patterns of golf balls made in accordance with the present invention. The examples are merely illustrative of the preferred embodiments of the present invention, and are not to be construed as limiting the invention, the scope of which is defined by the appended claims.
A triangular section of a dimple pattern based on a square dipyramid according to a particular embodiment of the present invention is illustrated in
In
Thus, according to the embodiment shown in
Thus, according to the embodiment shown in
A triangular section of a dimple pattern based on a square dipyramid according to a particular embodiment of the present invention is illustrated in
In
In a particular aspect of the embodiment illustrated in
In a further particular aspect of the embodiment illustrated in
In an alternative particular aspect of the embodiment illustrated in
In another further particular aspect of the embodiment shown in
Thus, according to the embodiment shown in
FIGS. SB & 5C show lines drawn at latitude angle 30° and latitude angle 60°, thereby dividing the triangular dimple section 10 into a polar region 15, an intermediate region 17, and an equatorial region 19. In
Thus, according to the embodiment shown in
A triangular section of a dimple pattern based on a square dipyramid according to a particular embodiment of the present invention is illustrated in
In
In
Thus, according to the embodiment shown n
When numerical lower limits and numerical upper limits are set forth herein, it is contemplated that any combination of these values may be used.
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.
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.
The present application is a continuation-in-part of U.S. patent application Ser. No. 16/587,455, filed Sep. 30, 2019, the entire disclosure of which is hereby incorporated herein by reference.
Number | Date | Country | |
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Parent | 16587455 | Sep 2019 | US |
Child | 17007090 | US |