US Patent 7169065 Multi-piece golf ball and manufacturing method thereof

This invention relates to a multi-layered, multi-piece golf ball that comprises a core, an intermediate layer, and a cover, wherein the core comprises a spherical body and ribs that are arranged on the surface of the spherical body and that have almost the same height as the thickness of the intermediate layer, wherein the intermediate layer fills a plurality of concave portions formed on the surface of the spherical body while being surrounded by the ribs. This arrangement enables the golf ball to have both high ball bounce resilience and a soft feel when hit.