Golf ball
Golf ball 28 has a first side face 32, a second side face 34 and a third side face 36. The first side face 32 is positioned between an edge E and a point P. The second side face 34 is positioned between the point P and a point Q. The third side face 36 is positioned between the point Q and a point R. Each side face 32, 24, 36 is inclined in the in-depth direction toward the inward side. An angle α 1 of the first side face 32 is 2.0° or greater and 11.0° or less. An angle α 2 of the second side face 34 and an angle α 3 of the third side face 36 are equal to or less than 30.0°. The angle α 3 is greater than the angle α 2 . The angle α 2 is greater than the angle α 1 . The golf ball 28 also has a curved face 38 . The curved face 38 is a part of a spherical surface.
1. A golf ball having numerous dimples on the surface thereof,
said dimple comprising a truncated cone part having a side face inclined in the in-depth direction from the edge toward the inward side,
an angle α 1 of said side face with respect to the radial direction being 2.0° or greater and 10.0° or less, and
wherein said dimple has a bowl-shaped part which is positioned at the center thereof.
2. The golf ball according to claim 1 , wherein the angle α 1 is 3.0° or greater and 10.0° or less.
3. The golf ball according to claim 1 , wherein the angle α 1 is 4.0° or greater and 9.0° or less.
4. A golf ball having numerous dimples on the surface thereof, said dimple comprising:
(1) a first truncated cone part having a side face inclined in the in-depth direction from the edge toward the inward side;
(2 ) a second truncated cone part having a side face inclined in the in-depth direction toward the inward side, and continuing to the first truncated cone part; and
(3) a bowl-shaped part which is positioned at the center thereof,
an angle α 1 of said side face of the first truncated cone part with respect to the radial direction being 2.0° or greater and 11.0° or less, and
wherein an angle α 2 of said side face of the second truncated cone part with respect to the radial direction is greater than the angle α 1 , and the angle α 2 is equal to or less than 30.0°.
5. The golf ball according to claim 4 , wherein the angle α 2 is equal to or less than 20.0°.
6. The golf ball according to claim 4 , wherein the angle α 2 is 1.0° or greater than the angle α 1 .
7. The golf ball according to claim 4 , wherein the angle α 2 is 2.0° or greater than the angle α 1 .
8. A golf ball having numerous dimples on the surface thereof, said dimple comprising:
(1) a first truncated cone part having a side face inclined in the in-depth direction from the edge toward the inward side;
(2) a second truncated cone part having a side face inclined in the in-depth direction toward the inward side, and continuing to the first truncated cone part;
(3) a third truncated cone part having a side face inclined in the in-depth direction toward the inward side, and continuing to the second truncated cone part; and
(4) a bowl-shaped part which is positioned at the center thereof,
an angle α 1 of said side face of the first truncated cone part with respect to the radial direction being 2.0° or greater and 11.0° or less, and
wherein an angle α 2 of said side face of the second truncated cone part with respect to the radial direction is greater than the angle α 1 , and the angle α 2 is equal to or less than 30.0°,
an angle α 3 of said side face of the third truncated cone part with respect to the radial direction is greater than the angle α 2 , and the angle α 3 is equal to or less than 30.0°.
9. The golf ball according to claim 8 , wherein the angle α 3 is equal to or less than 20.0°.