Dimple patterns for golf balls

Abstract

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.

What is claimed is: 
     
         1 . A golf ball having a spherical outer surface consisting of a first hemisphere and a second hemisphere separated by an equator, the first hemisphere consisting of a plurality of first hemisphere dimples disposed on the surface thereof and the second hemisphere consisting of a plurality of second hemisphere dimples disposed on the surface thereof, wherein each dimple is considered to be located in the hemisphere in which its center is positioned and no dimple has a center positioned on the equator, and wherein:
 the outer surface of the golf ball does not contain a great circle which is free of dimples;   the plurality of first hemisphere dimples are arranged in a first dimple pattern, wherein the first dimple pattern is rotationally symmetric about a polar axis, the plurality of second hemisphere dimples are arranged in a second dimple pattern, wherein the second dimple pattern is rotationally symmetric about the polar axis, and the first dimple pattern and the second dimple pattern are not identical;   each of the first dimple pattern and the second dimple pattern has a first aerodynamic coefficient magnitude and a first aerodynamic force angle at a Reynolds number of 230,000 and a spin ratio of 0.085, each of the first dimple pattern and the second dimple pattern has a second aerodynamic coefficient magnitude and a second aerodynamic force angle at a Reynolds number of 170,000 and a spin ratio of 0.110, and:
 (i) the absolute difference between the first aerodynamic coefficient magnitude of the first dimple pattern and the first aerodynamic coefficient magnitude of the second dimple pattern is no more than 0.005; 
 (ii) the absolute difference between the first aerodynamic force angle of the first dimple pattern and the first aerodynamic force angle of the second dimple pattern is no more than 0.5°; 
 (iii) the absolute difference between the second aerodynamic coefficient magnitude of the first dimple pattern and the second aerodynamic coefficient magnitude of the second dimple pattern is no more than 0.005; and 
 (iv) the absolute difference between the second aerodynamic force angle of the first dimple pattern and the second aerodynamic force angle of the second dimple pattern is no more than 0.5°. 
   
     
     
         2 . The golf ball of  claim 1 , wherein a majority of the first hemisphere dimples have a first plan shape, a majority of the second hemisphere dimples have a second plan shape, and the first plan shape and the second plan shape are different. 
     
     
         3 . The golf ball of  claim 1 , wherein a majority of the first hemisphere dimples have a first plan shape and a first profile shape, a majority of the second hemisphere dimples have a second plan shape and a second profile shape, the first plan shape and the second plan shape are the same, and the first profile shape and the second profile shape are different. 
     
     
         4 . The golf ball of  claim 1 , wherein the number of different dimple diameters of the first hemisphere dimples is not equal to the number of different dimple diameters of the second hemisphere dimples. 
     
     
         5 . The golf ball of  claim 1 , wherein the total number of dimples located in the first hemisphere is not equal to the total number of dimples located in the second hemisphere. 
     
     
         6 . The golf ball of  claim 1 , wherein the total number of dimples located in the first hemisphere is equal to the total number of dimples located in the second hemisphere, and wherein the number of different dimple diameters of the first hemisphere dimples is not equal to the number of different dimple diameters of the second hemisphere dimples. 
     
     
         7 . The golf ball of  claim 1 , wherein the absolute difference between the dimple surface coverage of the first hemisphere and the dimple surface coverage of the second hemisphere is 1.0 percentage point or greater. 
     
     
         8 . The golf ball of  claim 1 , wherein the absolute difference between the dimple surface coverage of the first hemisphere and the dimple surface coverage of the second hemisphere is 1.5 percentage points or greater. 
     
     
         9 . The golf ball of  claim 1 , wherein the absolute difference between the dimple volume of the first hemisphere and the dimple volume of the second hemisphere is 5.0×10 −4  in 3  or greater. 
     
     
         10 . The golf ball of  claim 1 , wherein the absolute difference between the dimple volume of the first hemisphere and the dimple volume of the second hemisphere is 7.5×10 −4  in 3  or greater. 
     
     
         11 . The golf ball of  claim 1 , wherein a majority of the first hemisphere dimples have a circular plan shape and a majority of the second hemisphere dimples have a circular plan shape. 
     
     
         12 . The golf ball of  claim 11 , wherein a majority of the first hemisphere dimples have a profile shape defined by a spherical curve and a majority of the second hemisphere dimples have a profile shape defined by a catenary curve. 
     
     
         13 . A golf ball having a spherical outer surface consisting of a first hemisphere and a second hemisphere separated by an equator, the first hemisphere consisting of a plurality of first hemisphere dimples disposed on the surface thereof and the second hemisphere consisting of a plurality of second hemisphere dimples disposed on the surface thereof, wherein each dimple is considered to be located in the hemisphere in which its center is positioned and no dimple has a center positioned on the equator, and wherein:
 the outer surface of the golf ball does not contain a great circle which is free of dimples;   the plurality of first hemisphere dimples are arranged in a first dimple pattern, wherein the first dimple pattern is rotationally symmetric about a polar axis, the plurality of second hemisphere dimples are arranged in a second dimple pattern, wherein the second dimple pattern is rotationally symmetric about the polar axis, and the first dimple pattern and the second dimple pattern are not identical;   each of the first dimple pattern and the second dimple pattern has a first aerodynamic coefficient magnitude and a first aerodynamic force angle at a Reynolds number of 230,000 and a spin ratio of 0.085, each of the first dimple pattern and the second dimple pattern has a second aerodynamic coefficient magnitude and a second aerodynamic force angle at a Reynolds number of 170,000 and a spin ratio of 0.110, and:
 (i) the absolute difference between the first aerodynamic coefficient magnitude of the first dimple pattern and the first aerodynamic coefficient magnitude of the second dimple pattern is no more than 0.005; 
 (ii) the absolute difference between the first aerodynamic force angle of the first dimple pattern and the first aerodynamic force angle of the second dimple pattern is no more than 0.5°; 
 (iii) the absolute difference between the second aerodynamic coefficient magnitude of the first dimple pattern and the second aerodynamic coefficient magnitude of the second dimple pattern is no more than 0.005; and 
 (iv) the absolute difference between the second aerodynamic force angle of the first dimple pattern and the second aerodynamic force angle of the second dimple pattern is no more than 0.5°; and 
   the first dimple pattern is different from the second dimple pattern such that one or more of the following is true:
 (i) a majority of the first hemisphere dimples have a first plan shape, a majority of the second hemisphere dimples have a second plan shape, and the first plan shape and the second plan shape are different; 
 (ii) a majority of the first hemisphere dimples have a first profile shape, a majority of the second hemisphere dimples have a second profile shape, and the first profile shape and the second profile shape are different; 
 (iii) the number of different dimple diameters of the first hemisphere dimples is not equal to the number of different dimple diameters of the second hemisphere dimples; 
 (iv) the total number of dimples located in the first hemisphere is not equal to the total number of dimples located in the second hemisphere; 
 (v) the absolute difference between the overall dimple surface coverage of the first hemisphere and the overall dimple surface coverage of the second hemisphere is 1.0 percentage points or greater; or 
 (vi) the absolute difference between the dimple volume of the first hemisphere and the dimple volume of the second hemisphere is 5.0×10 −4  in 3  or greater.