Golf ball dimple based on witch of Agnesi curve

Patent metadata

Field	Value
Publication number	US-9833665-B2
Application number	US-94514410-A
Country	US
Kind code	B2
Filing date	Nov 12, 2010
Priority date	Nov 12, 2010
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A golf ball having the contour wherein at least one dimple has the cross-section of the dimple surface based on a modified witch of Agnesi curve and defined by the equation in the form of:

y
⁡

(
x
)

=

-

C
1

⁢

a
3

x
2

+

C
2

⁢

a
2

+

C
1

⁢

a
3

(

d
2

)

2

+

C
2

⁢

a
2

wherein:
y is the vertical distance from the dimple apex,
x is the radial distance from the dimple apex,
a is equal to the radius of the circle in the witch of Agnesi,
d is the dimple diameter, and
C 1 and C 2 are constants that will produce a variety of dimple surfaces from a variety of functions.

First claim

What is claimed is:

1. A golf ball having a surface with a plurality of recessed dimples thereon, wherein the cross-section of at least one dimple is a curve defined by the equation:

y
⁡

(
x
)

=

-

C
1

⁢

a
3

x
2

+

C
2

⁢

a
2

+

C
1

⁢

a
3

(

d
2

)

2

+

C
2

⁢

a
2

where the chord plane represents y=0,
the center axis of the dimple represents x=0,
a is a constant equal to the radius of a circle having a center at x=0 and tangent to the curve at the center of the dimple,
C 1 and C 2 are constants, and
d is the dimple diameter; and
wherein the ratio between the chord volume, V c , of the dimple profile and the square of the dimple diameter, having a profile as defined d 2 , is:

0.0010
≤

V
c

d
2

≤

0.0040
.

2. The golf ball according to claim 1 , wherein the ratio between the chord volume, V c , of the dimple profile and the square of the dimple diameter, d 2 , is:

0.0015
≤

V
c

d
2

≤

0.0030
.

3. The golf ball according to claim 1 , wherein the curvature is unique at every point x when 0≦x≦d/2.

4. The golf ball according to claim 3 , wherein the maximum curvature as an absolute value at any point in the dimple profile is equal to or less than 200.

5. The golf ball according to claim 3 , wherein the maximum curvature as an absolute value at any point in the dimple profile is equal to or less than 100.

6. The golf ball according to claim 3 , wherein the maximum curvature as an absolute value at any point in the dimple profile is equal to or less than 50.

7. The golf ball according to claim 3 , wherein the volume ratio, R V , is from 0.01 to 0.50, as defined by the equation:

R
V

=

V
c

π
⁡

(

d
2

)

2

⁢

D
c

,

where D c , is the chord depth.

8. The golf ball according to claim 7 , wherein the volume ratio is from 0.15 to 0.35.

Assignees

• Madson Michael R
• Acushnet Co

Inventors

• Madson Michael R

Classifications

• A63B37/002

  Specified dimple diameter · CPC title

• A63B37/0017 Primary

  Specified total dimple volume · CPC title

• A63B37/0012

  Dimple profile, i.e. cross-sectional view · CPC title