Golf Ball with Non-Circular Dimples Having Circular Arc-Shaped Outer Peripheral Edges

Abstract

A golf ball provided with elliptical dimples. A golf ball provided with non-circular dimples, configured by forming the dimples in the surface of a sphere or of a pseudosphere which consists of a polyhedron. The dimples have a non-circular shape which has a major axis having a length at least 1.2 times greater than that of the minor axis of the shape, are each composed of a pair of circular arcs, and have a depth which causes the peripheral edges of the dimples to generate turbulence. The configuration reduces the separation width at the separation boundary to a level less than that of a golf ball having circular dimples, and this decreases the drag. The polyhedron can be substantially composed of triangles, pentagons, or hexagons.

1 . A golf ball having non-circular dimples in which the surface of a sphere is used as a land part and a plurality of dimples are formed on the land part, wherein some or all of said plurality of dimples are non-spherical dimples surrounded by peripheral edges formed by a pair of circular arcs having the same or different curvatures extending on both sides of the ridge lines connecting the vertices of polygons inscribed in the sphere, and the major axis along the ridge lines of the inscribed polyhedron with non-circular dimples is at least 1.2 times greater than the minor axis orthogonal to the ridge lines. 
     
     
         2 . A golf ball according to  claim 1  in which the outer shape of said dimples is an elliptical shape formed by a pair of circular arcs having the same curvature. 
     
     
         3 . A golf ball according to  claim 1  in which the polyhedron inscribed in said sphere is a regular 80- to 320-sided triangular polyhedron and 120-480 non-circular dimples extending along each ridge line are formed. 
     
     
         4 . A golf ball according to  claim 1  in which the polyhedron inscribed in said sphere is a regular 80-sided triangular polyhedron, wherein 120 non-circular dimples having peripheral edges are formed so as to extend along both sides of the ridge lines and at least one circular or polygonal dimple is formed in the land part surrounded by the non-circular dimples. 
     
     
         5 . A golf ball according to  claim 1  in which the polyhedron inscribed in said sphere is an octagonal, hexagonal, or a combined polyhedron consisting of pentagons and hexagons, wherein triangles are formed by dividing each polygon face with line segments extending from the vertices to the center of the face, and non-circular dimples extending along the ridge lines of each triangle are formed. 
     
     
         6 . A golf ball according to  claim 1  in which some or all of said plurality of dimples are non-circular dimples with peripheral edges consisting of pairs of circular arcs having the same or different curvatures extending along both sides of the central parts of ridge lines connecting the vertices of the polyhedron inscribed in the sphere forming the golf ball, wherein at least one circular or polygonal dimple is formed in the land part including the vertices of said inscribed polygons. 
     
     
         7 . A golf ball according to  claim 1  in which the peripheral edges of said dimples have edge angles and depths so that vertical vortices are generated by the airflow received when the golf ball flies.