Golf ball

Abstract

A golf ball has a plurality of dimples on a surface thereof. Each dimple has a center portion and an edge portion. The center portion has a bowl shape. The edge portion has a ring shape and is smoothly continuous with the center portion. A cross-sectional shape of the edge portion is a curved line that is convex outward in a radial direction of the golf ball. A sum Vc of volumes of the center portions and a sum Vd of volumes of the dimples satisfy the following mathematical formula: (Vd−Vc)/Vc≤2.15. A ratio of a number of the dimples, the center portion of each dimple having a circular contour and the edge portion of each dimple having a non-circular contour, to a total number of the dimples, is not less than 50%.

1 . A golf ball having a plurality of dimples on a surface thereof, wherein each dimple has a center portion having a bowl shape, and an edge portion smoothly continuous with the center portion and having a ring shape,
 wherein a cross-sectional shape of the edge portion is a curved line that is convex outward in a radial direction of the golf ball, and   wherein a sum Vc of volumes of the center portions and a sum Vd of volumes of the dimples satisfy the following mathematical formula:
   ( Vd−Vc )/ Vc≤ 2.15. 
   
     
     
         2 . The golf ball according to  claim 1 , wherein a ratio of a number of the dimples, the center portion of each dimple having a circular contour and the edge portion of each dimple having a non-circular contour, to a total number of the dimples, is not less than 50%. 
     
     
         3 . The golf ball according to  claim 1 ,
 wherein the cross-sectional shape of the edge portion is a circular arc, and   wherein a ratio (PL/CR) of a land ratio PL (%) of the surface of the golf ball to a curvature radius CR (mm) of the circular arc is not less than 1.0 and not greater than 5.0.