Sumitomo Rubber Industries Limited

Mu Instrument Trading Corp.

Hideki Sano

Hiroaki Tanaka

Yoshiyuki Okido

Yutaka Yoshida

Takayuki Saimen

Masaaki Kikuchi

Hiromasa Yamamoto

Hiroaki Matsubara

The present invention provides a multi-piece solid golf ball having excellent flight performance and excellent shot feel at the time of hitting, and a method of making the same having good workability. The present invention relates to a multi-piece solid golf ball comprising a core composed of a center and at least one core outer layer formed on the center, and a cover covering the core, wherein the core outer layer is formed from a rubber composition which does not contain zinc salt of unsaturated carboxylic acid.

Method of making a multi-piece solid golf ball

A method for manufacturing a golf ball in which the eccentricity of an inner core of the golf ball is greatly reduced. The method includes the steps of providing a mold which defines a mold cavity, positioning a vulcanized inner core in the mold cavity so as to define a shell space between the inner core and an inner surface of the mold cavity, introducing an unvulcanized rubber material into the shell space so that a layer of unvulcanized rubber covers the inner core, forming an intermediate product, removing the intermediate product from the mold, placing the intermediate product into a vulcanization mold cavity containing a dimple-forming interior surface and vulcanizing the layer of unvulcanized rubber and forming dimples in the rubber material during vulcanization.

Method for manufacturing golf ball

A core sphere or a wound-string core is held by a pair of bottom rollers and a pair of concave top rollers. Then, the bottom rollers are reciprocated in opposite directions respectively and rotated to rotate the core sphere or the wound-string core and wind rubber string, and a wound-string core of a predetermined diameter is obtained by pressurizing the core sphere or the wound-string core intermittently by the pair of top rollers with a predetermined pressure. Rotation frequency of the bottom roller is set to be 1100 rpm to 200 rpm, ratio of the rotation frequency of the bottom roller to number of the horizontal movement of the bottom roller is set to be 10:15 to 15:10, and ratio of pressurizing number of the top rollers to the number of the horizontal movement of the bottom roller is set to be 1:14 to 1:5.

Manufacturing apparatus and method for golf ball

A pair of unvulcanized half outer layer bodies are formed by metallic molds provided with first mold having a hemispherical convex portion and second mold having a hemispherical concave portion. A vulcanized inner core is put into either of half outer layer bodies, and a pair of half outer layer bodies are paired up to form a preparatory form which is to be vulcanization molded in metallic molds for vulcanization molding.

Apparatus for manufacturing a golf ball with an initial preparatory form having a seam

An apparatus for winding a string, made of rubber, on a core to form a wound string core. The apparatus is provided with plurality of string winding device, each of which is for winding a string on a core, a treatment device of string starting end which winds to fix a starting end of the string to the core, a treatment device of wound string end which fastens an end of the wound string core at the end of the winding process, and a core providing device for providing the core to the treatment device of string starting end.

Apparatus and method for manufacturing golf ball

A spherical object is positioned on a rotation stage, the rotation stage is rotated, and a deviation detector detects whether the spherical object deviates from the rotation stage or not. A rotation frequency of the rotation stage when the object deviates from the rotation stage is detected by a rotation frequency detector, and a judgement system judges whether the object is mass eccentric or not, comparing the detected rotation frequency with a predetermined rotation frequency which is set beforehand.

Apparatus and method for detecting mass eccentricity

A golf ball core and a method of making the same wherein remarkable reduction of eccentricity of an inner layer to an outer layer is accomplished, and mass-production of the golfball cores are possible. The golfball inner layer is penetrated into at least a part of a seam portion of the outer layer. A volume of an intrusive portion of the inner layer into the outer layer is arranged to be 1/300 to 1/5 of a volume of the outer layer, suppose the outer layer is a complete spherical shell. To form a core, an unvulcanized material is semi-vulcanized or vulcanized to form an outer layer half shell whose configuration is generally a hemispherical shell, and an unvulcanized inner layer forming material is put between the pair of outer layer half shells and vulcanizing pressed.

Growing community of inventors

Kobe, Japan

Hideki Sano