Golf ball

Abstract

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 (mm3) 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.

What is claimed is: 
     
         1 . A golf ball having a plurality of dimples on a surface thereof, wherein
 a trajectory calculated using a drag coefficient CD and a lift force coefficient CL obtained in an indoor test range which is a rule set by the United States Golf Association, on the basis of a model proposed by S. J. Quintavalla of the United States Golf Association and disclosed in “Science and Golf IV, Chapter 30, A Generally Applicable Model for the Aerodynamic Behavior of Golf Balls” published in 2002, by a program created in accordance with a manual provided by the United States Golf Association, 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, satisfies 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 3 ) of the dimples, and
 the vector angle A is 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. 
     
     
         2 . The golf ball according to  claim 1 , wherein a total number of the dimples is not less than 280 and not greater than 380. 
     
     
         3 . The golf ball according to  claim 1 , wherein the average volume Vave is not less than 1.40 mm 3  and not greater than 2.10 mm 3 . 
     
     
         4 . A golf ball having a plurality of dimples on a surface thereof, wherein
 a value (A min+5.0*Vave) in a trajectory calculated using a drag coefficient CD and a lift force coefficient CL obtained in an indoor test range which is a rule set by the United States Golf Association, on the basis of a model proposed by S. J. Quintavalla of the United States Golf Association and disclosed in “Science and Golf IV, Chapter 30, A Generally Applicable Model for the Aerodynamic Behavior of Golf Balls” published in 2002, by a program created in accordance with a manual provided by the United States Golf Association, 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, is not less than −38.98,   Vave being an average volume (mm 3 ) of the dimples,   A min being a minimum value (degree) of a vector angle A calculated by the following mathematical formula, in the trajectory,
   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. 
     
     
         5 . The golf ball according to  claim 4 , wherein a total number of the dimples is not less than 280 and not greater than 380. 
     
     
         6 . The golf ball according to  claim 4 , wherein the average volume Vave is not less than 1.40 mm 3  and not greater than 2.10 mm 3 .