Golf ball having non-planar parting line with non-circular dimples
View Patent ↗The present invention is directed to a golf ball comprising of non-concentric arcs defining a non-planar parting line on its spherical surface resulting in having a large size disparity between non-circular dimples in one hemisphere and adjacent non-circular dimples from the opposing hemisphere. The parting line is produced by a pair of adjacent non-circular dimples, wherein μ d indicates the average non-circular dimple diameter and N indicates dimples from the Northern hemisphere and those from the Southern hemisphere are indicated by S. A large disparity may be created, if the following condition is satisfied: μ d ( N ) μ d ( S ) > 1.25 or μ d ( N ) μ d ( S ) < 0.80 .
1. A golf ball having a non-planar parting line about non-circular dimples on its spherical surface, the parting line comprising:
non-concentric arcs having straight connecting line segments between the arcs, wherein each arc maintains a tangency with its connecting lines and a relief distance greater than or equal to 0.003 inches when measured from an average non-circular dimple diameter to one of the non-concentric arcs and an absolute relief distance of at least 0.001 inches when measured from all points on the non-circular dimple perimeter to one of the non-concentric arcs; and
a radius of each non-concentric arc relates to a corresponding average non-circular dimple perimeter diameter according to the equations:
r
A
<
μ
d
2
and
r
A
>
(
0.10
)
μ
d
2
wherein
r A is the radius of a non-concentric arc, and
μ d is the average non-circular dimple perimeter diameter found using the following equation:
μ
d
=
∑
i
=
0
n
2
r
i
n
and n≧25
wherein r i is the distance from the dimple plan shape centroid to a number of n points on the dimple perimeter.
2. The golf ball according to claim 1 , wherein the golf ball comprises:
a plane comprising a non-circular dimple center and the vertical axis through the center of the ball; and
another plane comprising the center of a corresponding non-concentric arc and said vertical axis through the center of the ball,
wherein these planes create an arc shift angle defined to the average non-circular dimple perimeter diameter by the equation:
θ
≤
π
μ
d
6
θ is the arc shift angle in radians.
3. The golf ball according to claim 1 , wherein adjacent non-circular dimples on opposing hemisphere sides of the parting line have a large size disparity which is defined by the equation:
μ
d
(
N
)
μ
d
(
S
)
>
1.25
or
μ
d
(
N
)
μ
d
(
S
)
<
0.80
μ d (N) being the average diameter of a non-circular dimple in the Northern hemisphere of the ball; and
μ d (S) being the average diameter of a non-circular dimple in the Southern hemisphere.
4. The golf ball according to claim 3 , wherein adjacent non-circular dimples on opposing hemisphere sides of the parting line have a large size disparity which is defined by the equation:
μ
d
(
N
)
μ
d
(
S
)
>
1.40
or
μ
d
(
N
)
μ
d
(
S
)
<
0.70
5. The golf ball according to claim 1 , wherein adjacent non-circular dimples on opposing hemisphere sides of the parting line are weighted more towards one hemisphere over the other, based on the equation:
C RP >1.5 or C RP <0.66
C RP is the dimple radius preference coefficient.
6. The golf ball according to claim 5 , wherein adjacent non-circular dimples on opposing hemisphere sides of the parting line are weighted more towards one hemisphere over the other, based on the equation:
C RP >2.0 or C RP <0.50
7. The golf ball according to claim 1 , wherein the golf ball comprises non-circular dimples and circular dimples.
8. The golf ball according to claim 1 , wherein the golf ball comprises non-circular dimples and circular dimples adjacent the non-planar parting line.
9. The golf ball according to claim 1 , wherein the dimple pattern of the ball is an icosahedron-based dimple pattern.
10. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a dodecahedron-based dimple pattern.
11. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a pentagonal dipyramid-based dimple pattern.
12. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a triangular dipyramid-based dimple pattern.
13. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a tetrahedron-based dimple pattern.
14. The golf ball according to claim 1 , wherein the dimple pattern of the ball is an icosidodecahedron-based dimple pattern.
15. The golf ball according to claim 1 , wherein the dimple pattern of the ball is octahedral-based dimple pattern.
16. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a cube-octahedral dimple pattern.
17. The golf ball according to claim 1 , wherein the dimple pattern of the ball is a hexagonal dipyramid dimple pattern.
18. The golf ball according to claim 1 , wherein the spherical surface is a cover formed from a urethane or a urea material.