Patent ID: 6413171
Filing Date: 2002-07-02
Classification: A63B

Abstract:
A golf ball having a plurality of dimples having a diameter of 1.8 to 4.6 mm formed in its surface, wherein a sum of high-speed region dimple operative volumes (HDOVs) of respective dimples of the plurality of dimples as calculated by the following high-speed region formula is 210 to 310 mm3, the high-speed region formula comprising, for each dimple of the plurality of dimples having a diameter D1 (mm) which is the largest portion in a dimple:determining a diameter range R1 containing the diameter D1 from Table 5; horizontally slicing the dimple at a position of a depth corresponding to a diameter D2 (mm) equal to a lower limit of the diameter range R1, thereby defining a first slice zone A1 of flat frustoconical shape having the diameters D1 and D2; multiplying the volume (mm3) of the slice zone A1 by a coefficient &agr;1 corresponding to the diameter range R1 given in Table 5 wherein the coefficients corresponding to the diameter ranges which are formed by diameters of larger than 3.8 mm are assigned to the heaviest weight and other weight is reduced roughly in a parabola toward the smallest diameter range which is formed by diameters smaller than 2.0 mm, thereby calculating a first imaginary slice volume V1 (mm3); horizontally slicing the dimple at a position of a depth corresponding to a diameter D3 (mm) equal to the lower limit of the diameter range R2 which is given one row below the preceding diameter range R1 in Table 5, thereby defining a second slice zone A2 of flat frustoconical shape having the diameters D2 and D3; multiplying the volume (mm3) of the slice zone A2 by a coefficient &agr;2 corresponding to the diameter range R2 given in Table 5, thereby calculating a second imaginary slice volume V2 (mm3); repeating the calculation of imaginary slice volumes for successive diameter ranges that are each one row below a preceding diameter range in Table 5 until the volume (mm3) of a slice zone An associated with a final diameter range Rn of less than 2 mm is multiplied by a coefficient &agr;n corresponding to the diameter range Rn, thereby calculating an n-th imaginary slice volume Vn (mm3; and summing the imaginary slice volumes calculated by the high-speed region formula to obtain a high-speed region dimple operative volume HDOV, HDOV(mm3)=V1+V2+. . . +Vn TABLE 5Diameter range R (mm)Coefficient &agr;&gE;4.41.004.2-4.41.004.0-4.21.003.8-4.01.003.6-3.80.953.4-3.60.903.2-3.40.853.0-3.20.802.8-3.00.702.6-2.80.602.4-2.60.502.2-2.40.402.0-2.20.30&lE;2.0â€‰0.20.