Dunlop Sports Company Limited

Sri Sports Limited

Sumitomo Rubber Industries Limited

A School Corporation Kansai University

Dunlap Sports Co. Ltd.

Hiroshi Hasegawa

Masahide Onuki

Takashi Nakano

Kazuyoshi Shiga

Toshiyuki Tarao

Kuniyasu Horiuchi

Hidetaka Inoue

Chiemi Mikura

Hitoshi Oyama

Sho Goji

Takashi Nakamura

Naruhiro Mizutani

Hiromasa Tsunashima

Yuki Motokawa

Yasushi Sugimoto

Akio Yamamoto

Hirotaka Nakamura

Masahiko Ueda

Kiyofumi Matsunaga

Hiroyuki Takeuchi

Takehiko Hyodo

Wataru Kimizuka

Yasuo Naito

Takuzo Iwatsubo

Yuuichiro Yoneyama

Takeshi Shimauchi

Kota Maeda

Akihiko Kobayashi

A golf club includes a club shaft having a first end, a second end, and an inner peripheral surface defining an inner space of the club shaft, and a weight piece installed on a first end side of the club shaft. The weight piece includes an insertion portion located in the inner space, and an engagement portion located outside the club shaft to engage the first end. The insertion portion includes a first portion and a second portion. The first portion has an outer diameter smaller than the first inner diameter. The second portion includes a large diameter portion having an outer diameter larger than the first inner diameter in a state before being placed in the club shaft, and at least one rigidity-lowered portion that elastically deforms the second portion so that the outer diameter of the large diameter portion becomes smaller when receiving an external force.

Golf club and weight piece for golf club

A headincludes a head body h, a face part Fp, and a connecting part Cn. The face part Fpincludes a face surface fand a face back surface f. The connecting part Cnconnects the face back surface fof the face part Fpand the head body hto each other. The connecting part Cnmay be provided at a position separated from a peripheral edge of the face back surface f. The peripheral edge of the face back surface fmay be separated from the head body h. The face part Fpmay include a face middle region Rand a face peripheral region R. The connecting part Cnmay be provided only in the face middle region R

Golf club head

A golf club comprises: a golf club shaft extending from its first end to second end in its axis direction; a golf club head attached to the second end of the golf club shaft; a grip attach to the first end of the golf club shaft and having a grip end; and a weight member attached to the golf club shaft. The specific gravity of the weight member is 2.5 or more. The length of the weight member is 20 mm or less. The weight member is disposed in a grip-end portion of the golf club shaft so that a mass distribution in the axis direction of the grip-end portion has a local maximum occurring at a position within the grip-end portion, wherein the grip-end portion is defined as extending from the grip end toward the second end by 40 mm in the axis direction.

Golf club

A hollow golf club headcomprises a face portionwhich includes a club facefor striking a ball, and a main bodyextending rearward of the head from the face portion. The face Portionis made of a low-specific-gravity material having a specific gravity of 4.0 or less. The main bodyis provided in its face portionside with a low stiffness zonewhere the stiffness is locally reduced.

Provided is a method of evaluating stability of a golf swing. The method comprises calculating a force indicator that represents a force that acts on a body of a golfer during the golf swing and evaluating stability of the golf swing according to a magnitude of the force indicator. In the calculating, the force indicator may be calculated during the golf swing made with a specific golf club, and in the evaluating, the stability of the golf swing may be evaluated as a characteristic of the specific golf club, in accordance with the magnitude of the force indicator.

Method of evaluating stability of golf swing

A hollow golf club head comprises a face part having a face for striking a ball, and a main body extending rearward from the face part. The main body is provided with a low-rigidity zone which comprises through holes and connecting portions arranged alternately along a peripheral edge of the face. The through holes penetrate the main body from the outside to the inside of the main body. The connecting portions extend in the front-back direction of the head, and include an oblique connecting portion comprising an oblique part inclined with respect to the front-back direction.

A golf club includes a head, a shaft, and a tip engagement part RT having a reverse-tapered shape and being disposed at a tip end portion of the shaft. The tip engagement part RT includes a sleevehaving a reverse-tapered shape and being fixed to the tip end portion of the shaft, and a spacerhaving a reverse-tapered shape and being externally fitted to the sleeve. The spacerhas a divided structure. The hosel partincludes a hosel hole. The hosel holeincludes a reverse-tapered holecorresponding to the shape of the outer surface of the tip engagement part RT. The hosel holeallows the sleeveto pass through the hosel hole. The tip engagement part RT is fitted to the reverse-tapered hole, and the sleeveis fitted inside the spacer

A golf clubincludes a tip engagement part RT having a reverse-tapered shape and being disposed at a tip end portion of a shaft, and a screw member. The tip engagement part RT includes a sleevefixed to the tip end portion of the shaft. The sleevehas a sleeve-side connection part. The screw memberhas a screw-side connection partthat can be detachably connected to the sleeve-side connection part, and a male screw part. The headhas a female screw part. When the screw memberis rotated in a first direction, the screw memberpresses the tip engagement part RT in an engaging direction. When the screw memberis rotated in a second direction, the screw memberpulls the tip engagement part RT in an engagement releasing direction.

A golf club headhaving a hollow (i) therein comprises a face portionhaving a facefor striking a ball, a crown portionforming the head top surface, and a sole portionforming a bottom of the head. One of or each of the crown portionand the sole portionis provided with a plurality of grooves bent in the same direction.

An object of the present invention is to provide a grip for sporting goods containing an acrylonitrile-butadiene based rubber as a base rubber and having an excellent grip performance and sustainability of grip performance under a wet condition. The present invention provides a grip for sporting goods comprising an outermost surface layer formed from a surface layer rubber composition, wherein the surface layer rubber composition contains (A) a base rubber and (B) a resin having a softening point in a range from 5&#xb0; C. to 120&#xb0; C., (A) the base rubber contains an acrylonitrile-butadiene based rubber, and (B) the resin is at least one type selected from the group consisting of a hydrogenated rosin ester, a disproportionated rosin ester, an ethylene-vinyl acetate copolymer, a coumarone resin, a phenol resin, a xylene resin and a styrene resin.

Grip for sporting goods and golf club

An object of the present invention is to provide a golf club grip having excellent adhesion between the grip body and the grip end thereof, and excellent durability. The present invention provides a golf club grip comprising a cylindrical grip body having a cylindrical inner layer and a cylindrical outer layer covering the cylindrical inner layer, and a grip end provided on an butt side end of the cylindrical grip body, wherein the cylindrical outer layer is interposed in at least a part of a space between a butt side end edge of the cylindrical inner layer and the grip end.

Golf club grip, golf club and method for producing golf club grip

An object of the present invention is to provide a golf club grip showing a good feeling both at hitting and at waggling. The present invention provides a golf club grip comprising a cylindrical portion for inserting a shaft, wherein the cylindrical portion has a compression strain in a range from 46% to 55% at a compression stress of 20 kg/cm, and a compression strain in a range from 63% to 69% at a compression stress of 120 kg/cm.

Golf club grip and golf club

An object of the present invention is to provide a golf club grip excellent in grip performance in a wet condition. The present invention provides a golf club grip formed from a rubber composition comprising a base rubber and a crosslinking agent, wherein the base rubber comprises a hydrogenated acrylonitrile-butadiene rubber and/or a carboxyl-modified acrylonitrile-butadiene rubber.

An object of the present invention is to provide a golf club shaft having excellent strength. The present invention provides a golf club shaft made of a fiber-reinforced epoxy resin material comprising a cured product of an epoxy resin composition and a reinforcing fiber, wherein the epoxy resin composition comprises at least one selected from the group consisting of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin and a novolac type epoxy resin, and a tetraglycidyl type epoxy resin as an epoxy resin component, and the cured product of the epoxy resin composition has a swelling ratio in a range from 20 mass % to 44 mass % in methyl ethyl ketone.

Golf club shaft

An object of the present invention is to provide a grip for sporting goods excellent in tensile strength and having a light weight. The present invention provides a grip for sporting goods comprising a cylindrical portion composed of a cylindrical inner layer and a cylindrical outer layer covering the cylindrical inner layer, wherein the cylindrical inner layer is a porous rubber layer or a porous resin layer, and the cylindrical outer layer is formed from a rubber composition containing an acrylonitrile-butadiene based rubber.

Growing community of inventors

Kobe, Japan

Hiroshi Hasegawa