Golf balls having dimple patterns arranged in dipyramid layouts are disclosed. The patterns may be arranged in triangular dipyramid, quadrilateral dipyramid, pentagonal dipyramid, or hexagonal dipyramid layouts. The dipyramid patterns have six, eight, ten, or twelve substantially identical dimple sections, where each dimple section is defined by a spherical triangle. The dimples in each of the identical dimple sections have at least two different dimple diameters including a minimum dimple diameter and a maximum dimple diameter. The resulting dimple patterns have a surface coverage of about 70 percent or less. The reduced surface coverage helps to reduce the flight of the golf balls.

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.

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.

Golf balls having three-dimensional shaped fret areas and methods of making the same are disclosed. The three-dimensional shaped fret areas have at least three edges that meet at an apex point or an apex surface. The three-dimensional shaped fret areas may have a three-dimensional irregular pyramid shape or a three-dimensional truncated irregular pyramid shape. The three-dimensional shaped fret areas create golf balls having increased traction upon impact with the playing surface.

The present invention is directed to a mold for forming the cover of a golf ball having a non-planar parting line on its spherical surface.

A golf ball can have a relatively large number of dimples on a surface thereof. A trajectory of the golf ball calculated under conditions of an initial speed of 260 ft/s, a launch angle of 15.0 degrees, and an initial backspin rate of 3000 rpm can satisfy the following mathematical formula:

Amin≥−5.0*Vave−38.98,

wherein A min represents a minimum value (degree) of a vector angle A in the trajectory, and Vave represents an average volume (mm.sup.3) of the dimples. The vector angle A can be calculated by the following mathematical formula:

A=ATAN(Vy/Vx),

wherein Vx represents a horizontal component of a speed of the golf ball, and Vy represents a vertical component of the speed of the golf ball.

A golf ball can have a large number of dimples on a surface thereof. A trajectory of the golf ball can be calculated under conditions of an initial speed of 260 ft/s, a launch angle of 15.0 degrees, and an initial backspin rate of 3000 rpm satisfying the following mathematical formula,

[00001]$\text{Amax}\ge \text{4}\text{.0}\text{*}\text{Vave + 13}\text{.10,}$

wherein Amax represents a maximum value (degree) of a vector angle A in the trajectory, and Vave represents an average volume (mm.sup.3) of the dimples. The vector angle A can be calculated by the mathematical formula

[00002]$\text{A}\text{=}\text{ATAN}\left(\text{Vy}/\text{Vx}\right),$

wherein Vx represents a horizontal component of a speed of the golf ball, and Vy represents a vertical component of the speed of the golf ball.

Golf balls include dimples for generating a turbulent boundary layer. At least some of the dimples include a fan-shape. The fan-shaped dimple has a plurality of blades. Each blade has a trailing edge flush with a land area of a spherical surface of the golf ball, a leading edge, and a side wall connected to the leading edge. The dimple also has a sloped floor extending from the trailing edge to the leading edge, a blade tip connecting the leading edge to the trailing edge at a distal end of the blade, and a blade root connecting the leading edge to the trailing edge at a proximal end of the blade.

Golf balls according to the present invention achieve flight symmetry and overall satisfactory flight performance due to a dimple surface volume ratio that is equivalent between opposing hemispheres despite the use of different dimple geometries, different dimple arrangements, and/or different dimple counts on the opposing hemispheres.

A golf ball dimple pattern based on a square dipyramid, i.e., two square pyramids connected base-to-base, is disclosed. The dimples are arranged within four substantially identical triangular sections on each of two substantially identical hemispheres of the ball.