Patent ID: 6527654
Filing Date: 2003-03-04
Classification: A63B

Abstract:
A golf ball having, on a surface thereof, a large number of non-circular dimples taking planar shapes other than a circle and a large number of circular dimples taking circular planar shapes,wherein a ratio of the number of the non-circular dimples to the number of all dimples is 77% to 92%, a ratio of the number of the circular dimples to the number of all the dimples is 8% to 23%, the non-circular dimples include plural kinds of dimples taking specific shapes to satisfy conditions (A) and (B) which will be described below: (A) a contour line in a planar shape is formed by a combination of a semicircle and a circular arc or a combination of a semicircle and an elliptic arc; and (B) the contour line does not have a convex portion therein, and a ratio of the total number of the dimples taking specific shapes to all the non-circular dimples is 80% or more, when the number of a certain kind of dimples which contour line length is minimum in kinds having a specific shape and a dimple number ratio of 5% or more is represented by Ns and the number of a certain kind of dimples which contour line length is maximum in kinds having a specific shape and a dimple number ratio of 5% or more is represented by Nb, a ratio (Ns/Nb) is 20/80 to 80/20, and a dimple pattern is rotation symmetrical at an angle of 120 degrees or 90 degrees by setting a pole to be a center of rotation in both of two hemispheres obtained by a division through a parting surface of a mold.